[ { "id": "https://authors.library.caltech.edu/records/ek5xb-5xq65", "eprint_status": "archive", "datestamp": "2026-03-04 17:38:16", "lastmod": "2026-03-04 17:38:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moorman-Ruth", "name": { "family": "Moorman", "given": "Ruth" }, "orcid": "0000-0001-5054-1559" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "name": { "family": "Youngs", "given": "Madeleine K." }, "orcid": "0000-0002-3395-8165" }, { "name": { "family": "Stewart", "given": "Andrew L." }, "orcid": "0000-0001-5861-4070" } ] }, "title": "The Antarctic coastal ocean heat budget is dominated by heat loss to land ice melt", "ispublished": "pub", "full_text_status": "public", "note": "

© 2026 the Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).

\n\n
R.M. thanks Y. Si for answering questions about the LLC270-SO base configuration, M. Mazloff for help deciphering MITgcm heat budget terms, and F. A. Haumann for asking what meltwater temperature was used in R.M.’s prior meltwater perturbation work. We further thank two reviewers for time and attention.
\n\n
R.M. and A.F.T. were supported by the National Science Foundation award OPP-2332460 and an Impact Grant from the Resnick Sustainability Institute at the California Institute of Technology. R.M. was additionally supported by the General Sir John Monash Foundation. A.L.S. and M.K.Y. were supported by the National Science Foundation, under award number OPP-2023244. A.L.S. was additionally supported by the National Science Foundation award OCE-1751386.
\n\n
\n\n\n\n\n
MITgcm base code and user manual are available from the project website, http://mitgcm.org/. Code needed to build and run the LLC270-SO simulations used in this work are provided at https://zenodo.org/records/17203352. The ERA-Interim atmospheric reanalysis product used to force the LLC270-SO runs has been depreciated and replaced with ERA5 since it was accessed for this study (access date: 5th December 2019). ERA-Interim is now only available on request from ECMWF, see https://ecmwf.int/en/forecasts/datasets/browse-reanalysis-datasets. No physical materials were generated for this study. All data and code needed to evaluate and reproduce the conclusions in the paper are present in the paper and/or the Supplementary Materials.
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\n\n\n\n
\n\n\n
\n\n

Figs. S1 to S13 (PDF)

", "abstract": "

Transport of warm Circumpolar Deep Water (CDW) across the Antarctic continental shelf break is the primary source of heat to Antarctica's marginal seas. Net heat supplied by CDW is ultimately lost to: (i) the ocean surface, either to the atmosphere or sea ice, or (ii) the ice sheet, by melting the base of ice shelves and calved icebergs. Ocean models often neglect the heat exchange needed to melt ice shelves and icebergs. Simulations presented here indicate that this omits the largest ocean heat sink on the Antarctic continental shelf, representing 60% of heat supplied across the shelf break. Suppressing this heat sink in simulations drives enhanced heat loss to the atmosphere through thinned sea ice cover as well as nonlocal reductions in heat supply to the continental shelf via sea ice–mediated stratification changes. These results highlight a source of climate model bias and clarify the dynamics of heat transport to Antarctic ice shelves.

", "date": "2026-02-27", "date_type": "published", "publication": "Science Advances", "volume": "12", "number": "9", "publisher": "American Association for the Advancement of Science", "pagerange": "eaec7443", "issn": "2375-2548", "official_url": "https://authors.library.caltech.edu/records/ek5xb-5xq65", "funders": { "items": [ { "grant_number": "OPP-2332460" }, {}, { "agency": "General Sir John Monash Foundation", "grant_number": "John Monash Scholarship" }, { "grant_number": "OPP-2023244" }, { "grant_number": "OCE-1751386" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/sciadv.aec7443", "pmcid": "PMC12935052", "primary_object": { "basename": "sciadv.aec7443.pdf", "url": "https://authors.library.caltech.edu/records/ek5xb-5xq65/files/sciadv.aec7443.pdf" }, "related_objects": [ { "basename": "sciadv.aec7443_sm.pdf", "url": "https://authors.library.caltech.edu/records/ek5xb-5xq65/files/sciadv.aec7443_sm.pdf" } ], "pub_year": "2026", "author_list": "Moorman, Ruth; Thompson, Andrew F.; et al." }, { "id": "https://authors.library.caltech.edu/records/k6ehd-0n632", "eprint_status": "archive", "datestamp": "2025-12-18 21:33:42", "lastmod": "2025-12-18 21:33:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Bach", "given": "Eviatar" }, "orcid": "0000-0002-9725-0203" }, { "name": { "family": "Baptista", "given": "Ricardo" }, "orcid": "0000-0002-0421-890X" }, { "id": "Calvello-Edoardo", "name": { "family": "Calvello", "given": "Edoardo" }, "orcid": "0009-0002-6722-823X" }, { "id": "Chen-Bohan", "name": { "family": "Chen", "given": "Bohan" }, "orcid": "0000-0002-4159-076X" }, { "id": "Stuart-A-M", "name": { "family": "Stuart", "given": "Andrew" }, "orcid": "0000-0001-9091-7266" } ] }, "title": "Learning enhanced ensemble filters", "ispublished": "pub", "full_text_status": "public", "keywords": "Data assimilation; Ensemble filter; Neural operators", "note": "

© 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

\n\n

The authors are grateful to Arnaud Doucet for pointing them to work on the set transformer. The authors acknowledge support from a Department of Defense (DoD) Vannevar Bush Faculty Fellowship (award N00014-22-1-2790), NSF award AGS1835860 and from the Resnick Sustainability Institute; all support is held by AMS.

\n\n

The authors acknowledge support from a Department of Defense (DoD) Vannevar Bush Faculty Fellowship (award N00014-22-1-2790), NSF award AGS1835860 and from the Resnick Sustainability Institute; all support is held by AMS.

\n\n
The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:
\n
Andrew Stuart reports financial support was provided by US Department of Defense. Andrew Stuart reports financial support was provided by National Science Foundation. Andrew Stuart reports financial support was provided by California Institute of Technology Resnick Sustainability Institute. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
", "abstract": "

The filtering distribution in hidden Markov models evolves according to the law of a mean-field model in state–observation space. The ensemble Kalman filter (EnKF) approximates this mean-field model with an ensemble of interacting particles, employing a Gaussian ansatz for the joint distribution of the state and observation at each observation time. These methods are robust, but the Gaussian ansatz limits accuracy. Here this shortcoming is addressed by using machine learning to map the joint predicted state and observation to the updated state estimate. The derivation of methods from a mean field formulation of the true filtering distribution suggests a single parametrization of the algorithm that can be deployed at different ensemble sizes. And we use a mean field formulation of the ensemble Kalman filter as an inductive bias for our architecture.

\n

To develop this perspective, in which the mean-field limit of the algorithm and finite interacting ensemble particle approximations share a common set of parameters, a novel form of neural operator is introduced, taking probability distributions as input: a measure neural mapping (MNM). A MNM is used to design a novel approach to filtering, the MNM-enhanced ensemble filter (MNMEF), which is defined in both the mean-field limit and for interacting ensemble particle approximations. The ensemble approach uses empirical measures as input to the MNM and is implemented using the set transformer, which is invariant to ensemble permutation and allows for different ensemble sizes. In practice fine-tuning of a small number of parameters, for specific ensemble sizes, further enhances the accuracy of the scheme. The promise of the approach is demonstrated by its superior root-mean-square-error performance relative to leading methods in filtering the Lorenz '96 and Kuramoto-Sivashinsky models.

", "date": "2026-02-15", "date_type": "published", "publication": "Journal of Computational Physics", "volume": "547", "publisher": "Elsevier", "pagerange": "114550", "issn": "0021-9991", "official_url": "https://authors.library.caltech.edu/records/k6ehd-0n632", "funders": { "items": [ { "grant_number": "N00014-22-1-2790" }, { "grant_number": "AGS-1835860" }, {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Engineering-and-Applied-Science" } ] }, "doi": "10.1016/j.jcp.2025.114550", "pub_year": "2026", "author_list": "Bach, Eviatar; Baptista, Ricardo; et al." }, { "id": "https://authors.library.caltech.edu/records/fhdna-rhg81", "eprint_status": "archive", "datestamp": "2026-02-17 22:27:16", "lastmod": "2026-02-17 22:27:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulze-Benjamin-C", "name": { "family": "Schulze", "given": "Benjamin C." }, "orcid": "0000-0002-6405-8872" }, { "id": "Kenseth-Christopher-M", "name": { "family": "Kenseth", "given": "Christopher M." }, "orcid": "0000-0003-3188-2336" }, { "id": "Ward-Ryan-X", "name": { "family": "Ward", "given": "Ryan X." }, "orcid": "0000-0003-2317-3310" }, { "id": "Pennington-Elyse-A", "name": { "family": "Pennington", "given": "Elyse A." }, "orcid": "0000-0003-1736-2342" }, { "name": { "family": "Seltzer", "given": "Karl M." }, "orcid": "0000-0002-2175-5678" }, { "name": { "family": "Van Rooy", "given": "Paul" } }, { "name": { "family": "Tasnia", "given": "Afsara" } }, { "name": { "family": "Barletta", "given": "Barbara" } }, { "name": { "family": "Meinardi", "given": "Simone" } }, { "name": { "family": "Ehrenfels", "given": "Melissa A." }, "orcid": "0000-0003-3634-2195" }, { "name": { "family": "Jensen", "given": "Andrew R." }, "orcid": "0000-0003-0238-2367" }, { "id": "Huang-Yuanlong", "name": { "family": "Huang", "given": "Yuanlong" }, "orcid": "0000-0002-6726-8904" }, { "id": "Parker-Harrison-A", "name": { "family": "Parker", "given": "Harrison A." }, "orcid": "0000-0002-0041-2764" }, { "id": "Hasheminassab-Sina", "name": { "family": "Hasheminassab", "given": "Sina" }, "orcid": "0000-0002-4422-8547" }, { "name": { "family": "Day", "given": "Douglas A." }, "orcid": "0000-0003-3213-4233" }, { "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "name": { "family": "de Gouw", "given": "Joost" }, "orcid": "0000-0002-0385-1826" }, { "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "name": { "family": "Blake", "given": "Donald R." } }, { "name": { "family": "Barsanti", "given": "Kelley C." }, "orcid": "0000-0002-6065-8643" }, { "name": { "family": "Pye", "given": "Havala O. T." }, "orcid": "0000-0002-2014-2140" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Complex Effects of Reduced Mobile Source Emissions on Submicron Particulate Matter Concentrations in Los Angeles", "ispublished": "pub", "full_text_status": "public", "keywords": "aerosol; emissions; SOA; mobile sources; nitrogen oxides", "note": "

© 2025 American Chemical Society.

\n\n

We thank Nga Lee Ng, Brian McDonald, Carsten Warneke, and Michael Kleeman for helpful discussions. We also thank the Caltech Facilities Department, and in particular Raul Turcios, for their help during the campaign. This research was funded by the NOAA Climate Program Office’s Oceanic and Atmospheric Research Program (Grants NA21OAR4310224 and NA21OAR4310222) and California Air Resources Board (Contract No. 21RD017). The University of Colorado groups were supported by NSF AGS (Grant 2206655), NASA (Grants 80NSSC21K1451 and 80NSSC23K0828), and a CIRES Innovative Research Project. We thank the Resnick Sustainability Institute for funding the criteria pollutant instrumentation on the Caltech campus. The views expressed in this article are those of the authors and do not necessarily reflect the views or policies of the U.S. EPA. NOAA, or the California Air Resources Board.

\n\n

Further descriptions of analytical methods, statistical analyses, and model architectures and parametrizations and of analyses that support the primary arguments, along with associated figures (PDF)

", "abstract": "
\n

Despite considerable reductions in mobile source emissions, annual average aerosol concentrations measured in Los Angeles using Federal Reference Methods (FRM) have not appreciably declined over the past decade. Here, we use submicron aerosol measurements and zero-dimensional modeling to quantify the impacts of these emission reductions on aerosol formation in Pasadena, CA, during the late spring and summer of 2022. Reductions in secondary organic aerosol (SOA) concentrations expected from reduced mobile source emissions appear to have been largely offset by increases in hydroxyl radical concentrations, an indirect effect of reduced nitrogen oxide (NOx) emissions. As a result, while the predicted contribution of mobile sources to the SOA burden has declined from ∼50% in 2010 to only ∼25% in 2022, concentrations of locally formed SOA have remained relatively constant. In contrast, reductions in mobile source NOx emissions have likely reduced overnight production of nitric acid and ammonium nitrate (AN) aerosol. We provide indirect evidence that FRM measurements may have failed to capture the reduction in AN since 2010 due to the evaporation of semivolatile species from FRM filter samples. Our results suggest that given the effectiveness of historical regulatory efforts aimed at mobile sources, and on-road sources in particular, additional reductions in submicron aerosol concentrations in Los Angeles will likely require increased focus on abating emissions from nonroad and area sources.

\n
", "date": "2026-02-13", "date_type": "published", "publication": "ACS ES&T Air", "volume": "3", "number": "2", "publisher": "American Chemical Society", "pagerange": "313-325", "issn": "2837-1402", "official_url": "https://authors.library.caltech.edu/records/fhdna-rhg81", "funders": { "items": [ { "grant_number": "NA21OAR4310224" }, { "grant_number": "NA21OAR4310222" }, { "grant_number": "21RD017" }, { "grant_number": "2206655" }, { "grant_number": "80NSSC21K1451" }, { "grant_number": "80NSSC23K0828" }, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-Chemistry-and-Chemical-Engineering" }, { "id": "Division-of-Engineering-and-Applied-Science" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsestair.5c00199", "primary_object": { "basename": "ea5c00199_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fhdna-rhg81/files/ea5c00199_si_001.pdf" }, "pub_year": "2026", "author_list": "Schulze, Benjamin C.; Kenseth, Christopher M.; et al." }, { "id": "https://authors.library.caltech.edu/records/dctqh-4aa10", "eprint_status": "archive", "datestamp": "2026-01-13 17:16:17", "lastmod": "2026-01-13 17:16:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Deck-Katherine", "name": { "family": "Deck", "given": "Katherine" }, "orcid": "0009-0001-0572-7642" }, { "id": "Braghiere-Renato-K", "name": { "family": "Braghiere", "given": "Renato K." }, "orcid": "0000-0002-7722-717X" }, { "id": "Renchon-Alexandre-A", "name": { "family": "Renchon", "given": "Alexandre A." }, "orcid": "0000-0002-9521-5092" }, { "id": "Sloan-Julia", "name": { "family": "Sloan", "given": "Julia" }, "orcid": "0000-0003-0200-063X" }, { "id": "Bozzola-Gabriele", "name": { "family": "Bozzola", "given": "Gabriele" }, "orcid": "0000-0003-3696-6408" }, { "id": "Speer-Edward", "name": { "family": "Speer", "given": "Edward" } }, { "name": { "family": "Ben Mackay", "given": "J." } }, { "id": "Reddy-Teja", "name": { "family": "Reddy", "given": "Teja" }, "orcid": "0009-0004-3319-825X" }, { "id": "Phan-Kevin", "name": { "family": "Phan", "given": "Kevin" } }, { "name": { "family": "Gagn\u00e9\u2010Landmann", "given": "Anna L." } }, { "name": { "family": "Li", "given": "Yuchen" }, "orcid": "0000-0002-7518-5359" }, { "id": "Yatunin-Dennis", "name": { "family": "Yatunin", "given": "Dennis" } }, { "id": "Charbonneau-Andrew", "name": { "family": "Charbonneau", "given": "Andrew" } }, { "id": "Efrat\u2010Henrici-Nat", "name": { "family": "Efrat\u2010Henrici", "given": "Nat" } }, { "id": "Bach-Eviatar", "name": { "family": "Bach", "given": "Eviatar" }, "orcid": "0000-0002-9725-0203" }, { "id": "Ma-Shuang", "name": { "family": "Ma", "given": "Shuang" }, "orcid": "0000-0002-6494-724X" }, { "name": { "family": "Gentine", "given": "Pierre" }, "orcid": "0000-0002-0845-8345" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Bloom-A-Anthony", "name": { "family": "Bloom", "given": "A. Anthony" }, "orcid": "0000-0002-1486-1499" }, { "id": "Wang-Yujie", "name": { "family": "Wang", "given": "Yujie" }, "orcid": "0000-0002-3729-2743" }, { "name": { "family": "Longo", "given": "Marcos" }, "orcid": "0000-0001-5062-6245" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "ClimaLand: A Land Surface Model Designed to Enable Data-Driven Parameterizations", "ispublished": "pub", "full_text_status": "public", "keywords": "land surface modeling", "note": "

© 2026 The Author(s). Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

\n\n
\n

This research was supported by Schmidt Sciences, LLC, and by the Resnick Sustainability Institute at Caltech. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. We thank Lee Barbour and Mingbin Huang for providing the SV62 site data for the layered soil experiment, Dani Or and Peter Lehmann for providing the bare soil evaporation data, Yongjiu Dai and Nan Wei for helping us to understand the SoilGrids data, and Natan Holtzmann for aiding our initial flux tower simulations. We would also like to thank Elias Massoud, John Worden, Alex Norton, Victoria Meyer and Paul Levine for early discussions regarding ClimaLand. We acknowledge high-performance computing support from Caltech's Resnick High Performance Computing Center and the Derecho system (Computational and Information Systems Laboratory, 2023) provided by the National Center for Atmospheric Research (NCAR), sponsored by the National Science Foundation.

\n
\n\n

All code used in the examples is available (Deck et al., 2025), and the required data will download automatically when scripts are run, with the exception of hourly forcing data from ERA5 due to file size constraints and the layered soil infiltration measurement data. The ERA5 data was obtained from Hersbach et al. (2023). The measurement data used in the layered soil infiltration example is checked into the repository on a protected branch of Deck et al. (2025): https://github.com/CliMA/ClimaLand.jl/tree/paper/layered_soil_plots.

", "abstract": "

Land surface models (LSMs) are essential tools for simulating the coupled climate system, representing the dynamics of water, energy, and carbon fluxes on land and their interaction with the atmosphere. However, parameterizing sub\u2010grid processes at the scales relevant to climate models (~10–100 km) remains a considerable challenge. The parameterizations typically have a large number of unknown and often correlated parameters, making calibration and uncertainty quantification difficult. Moreover, many existing LSMs are not readily adaptable to the incorporation of modern machine learning (ML) parameterizations trained with in situ and satellite data. This article presents the first version of ClimaLand, a new LSM designed for overcoming these limitations, including a description of the core equations underlying the model, the results of an extensive set of validation exercises, and an assessment of the computational performance of the model. We show that ClimaLand can leverage graphics processing units for computational efficiency, and that its modular architecture and high\u2010level programming language, Julia, allows for integration with ML libraries. In the future, this will enable efficient simulation, calibration, and uncertainty quantification with ClimaLand.

", "date": "2026-01", "date_type": "published", "publication": "Journal of Advances in Modeling Earth System (JAMES)", "volume": "18", "number": "1", "publisher": "American Geophysical Union", "pagerange": "e2025MS005118", "issn": "1942-2466", "official_url": "https://authors.library.caltech.edu/records/dctqh-4aa10", "funders": { "items": [ {}, { "grant_number": "-" }, {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2025ms005118", "primary_object": { "basename": "J Adv Model Earth Syst - 2026 - Deck - ClimaLand A Land Surface Model Designed to Enable Data\u2010Driven Parameterizations.pdf", "url": "https://authors.library.caltech.edu/records/dctqh-4aa10/files/J Adv Model Earth Syst - 2026 - Deck - ClimaLand A Land Surface Model Designed to Enable Data\u2010Driven Parameterizations.pdf" }, "pub_year": "2026", "author_list": "Deck, Katherine; Braghiere, Renato K.; et al." }, { "id": "https://authors.library.caltech.edu/records/sy2ah-z3g38", "eprint_status": "archive", "datestamp": "2026-01-08 00:27:48", "lastmod": "2026-01-08 00:27:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Geyman-Emily-C", "name": { "family": "Geyman", "given": "Emily C." }, "orcid": "0000-0003-4349-9350" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Resolving the changing pace of Arctic rivers", "ispublished": "pub", "full_text_status": "public", "keywords": "Cryospheric science; Hydrology", "note": "

© The Author(s), under exclusive licence to Springer Nature Limited 2025.

\n\n

We thank the Huslia, Beaver and Alakanuk Tribal and Village Councils for river and land access, and S. Huffman, D. Dayton, C. Wiehl, K. Vanderpool, R. Williams, T. Hamilton and the Yukon River Inter-Tribal Watershed Council for logistical support. The photo in Fig. 1d was provided by T. Hamilton on behalf of the Alakanuk Tribal IGAP. This work was supported by NSF Award 2127442 and Caltech’s Resnick Sustainability Institute. E.C.G. was supported by the NSF Graduate Research Fellowships Program and the Fannie and John Hertz Foundation.

\n\n

This work was supported by NSF Award 2127442 and Caltech’s Resnick Sustainability Institute. E.C.G. was supported by the NSF Graduate Research Fellowships Program and the Fannie and John Hertz Foundation.

\n\n

The database of riverbank boundaries digitized from Landsat satellite imagery and used to reconstruct river migration rates over the period 1972–2020 is available on Zenodo at https://doi.org/10.5281/zenodo.15002956 (ref. 79). Note that this study builds on an existing dataset of bank positions of n = 10 Arctic river reaches digitized in ref. 13. This original dataset is also available on Zenodo at https://doi.org/10.5281/zenodo.7556050 (ref. 80). The Landsat image archives are accessible through the USGS EarthExplorer (https://earthexplorer.usgs.gov/). The Supporting Information includes a complete list of Landsat scene IDs utilized in this study. The global aboveground biomass map from ref. 42 is available at https://doi.org/10.3334/ORNLDAAC/1763. The NDVI trend (greening versus browning) statistics from ref. 41 are available at https://doi.org/10.3334/ORNLDAAC/1576. Streamflow data are available from the USGS National Water Dashboard (https://dashboard.waterdata.usgs.gov/app/nwd/en/) and the National Hydrological Service of Canada (https://wateroffice.ec.gc.ca/). The remote-sensing-derived estimates of riverine suspended sediment concentrations from ref. 26 are available at https://figshare.com/s/dde3bffd8e12227e2b26. The permafrost mean annual ground temperature observations are available from ref. 51 at https://doi.org/10.1594/PANGAEA.930669. The Cold Regions Research and Engineering Laboratory (CRREL) Ice Jam Database47 is available at https://icejam.sec.usace.army.mil/. The Alaska permafrost map of ref. 36 is available at https://doi.org/10.5066/F7C53HX6.

\n\n

The code used to perform this analysis is archived on Zenodo at https://doi.org/10.5281/zenodo.15002956 (ref. 79).

\n\n

Supplementary Discussion, Figs. 1–35 and Tables 1–3 (PDF)

\n\n

Extended Data Table 1 Summary of channel migration rate trends and environmental parameters for the n = 20 sites shown in Fig. 2 

\n

Extended Data Table 2 An extension of Extended Data Table 1 listing the variability in floodplain above-ground biomass (AGB), NDVI trend, and permafrost (PF) abundance for each river reach

\n

Extended Data Fig. 1 Potential pitfalls of inferring changes to river migration rates from optical satellite timeseries

\n

Extended Data Fig. 2 An illustration of how our curvature-based approach avoids overcounting the apparent channel migration from image co-registration errors

\n

Extended Data Fig. 3 A synthetic experiment to test for bias in the extraction of migration rates from historical Landsat timeseries

\n

 

", "abstract": "

Arctic rivers mobilize vast stocks of permafrost carbon as they migrate across floodplains. However, there is no consensus about whether Arctic rivers are responding to regional warming by speeding up or slowing down. Here we reconstruct migration rates over the period 1972–2020 for Arctic and sub-Arctic rivers spanning approximately 1,500 km of distance and a variety of channel sizes and floodplain environments. We find that rivers in warmer, discontinuous permafrost settings experienced a systematic acceleration over the past 50 years, whereas rivers in colder, continuous permafrost regions experienced a systematic slowdown. We identify two competing mechanisms responsible for this bifurcating behaviour: thaw of permafrost floodplains has driven faster migration, whereas a decline in the intensity of river-ice breakup has slowed migration. Using a mechanistic model, we find that the relative balance of these two controls is well described by air temperature, revealing a simple organizing framework for how Arctic rivers respond to warming.

", "date": "2026-01", "date_type": "published", "publication": "Nature Climate Change", "volume": "16", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "77-86", "issn": "1758-678X", "official_url": "https://authors.library.caltech.edu/records/sy2ah-z3g38", "funders": { "items": [ { "grant_number": "RISE-2127442" }, { "grant_number": "-" }, { "grant_number": "-" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41558-025-02512-w", "primary_object": { "basename": "41558_2025_2512_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/sy2ah-z3g38/files/41558_2025_2512_MOESM1_ESM.pdf" }, "pub_year": "2026", "author_list": "Geyman, Emily C. and Lamb, Michael P." }, { "id": "https://authors.library.caltech.edu/records/a7fna-em358", "eprint_status": "archive", "datestamp": "2025-12-02 18:23:37", "lastmod": "2025-12-02 18:23:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Xu", "given": "Chao" }, "orcid": "0000-0001-9495-294X" }, { "name": { "family": "Cassar", "given": "Nicolas" }, "orcid": "0000-0003-0100-3783" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "name": { "family": "Zhang", "given": "Yuchen" } }, { "name": { "family": "Wang", "given": "Haili" } }, { "name": { "family": "Liu", "given": "Xin" }, "orcid": "0000-0002-7925-9618" }, { "name": { "family": "Huang", "given": "Bangqin" }, "orcid": "0000-0003-2279-6241" } ] }, "title": "The overlooked contribution of the seasonal mixed layer pump to carbon export in low-latitude oceans", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon cycle; Marine chemistry", "note": "

© The Author(s) 2025. This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.

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B.H. and X.L. are supported by the National Natural Science Foundation of China (Nos. 42130401, 42141002, 42421004). C.X. is supported by the China Scholarship Council to study at Duke University as a joint PhD student (No. 202306310164). A.T. is supported by the Resnick Sustainability Institute at the California Institute of Technology and the Ginkgo Foundation.

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Public floats data used in this study are downloaded from the Global Data Assembly Centers (ftp://usgodae.org/pub/outgoing/argo). The monthly remotely-sensed NPP is downloaded from the Ocean Productivity website (http://sites.science.oregonstate.edu/ocean.productivity). The weekly mixed layer depth and sea surface Chl a are downloaded from the E.U. Copernicus Marine Environment Monitoring Service (https://doi.org/10.48670/moi-00052 and https://doi.org/10.48670/moi-00046). Climatological nitrate data are downloaded from the World Ocean Atlas 2023. All data used in this study are available from Zenodo at https://zenodo.org/records/17114326.

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All codes are available from Zenodo at https://zenodo.org/records/17114326.

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Supplementary Information

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Peer Review file

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", "abstract": "
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The seasonal mixed layer pump (MLP) is an important pathway transporting organic carbon from the upper ocean to the ocean interior. While the MLP’s export role has been well-studied in high latitudes, its contribution in low latitudes remains uncertain. Here, we quantify the seasonal MLP-driven carbon export (EMLP) in low-latitude oceans using data from 26 biogeochemical profiling floats. Our analysis reveals that EMLP ranges from −0.9 to 7.6 g C m−2 yr−1, contributing up to 53% of carbon export in certain areas. We find the relative positions of the mixed layer depth, euphotic depth, and nitracline depth regulate EMLP strength in low-latitude oceans. Global extrapolation of these observations across low-latitude oceans yields a total EMLP of 0.07 ± 0.02 Pg C yr−1, 75% higher than previous estimates, underscoring the previously underestimated role of the seasonal MLP in low-latitude oceans. These results reveal the controlling mechanisms of low-latitude seasonal MLP and highlight its disproportionately important role in regional ecosystems, particularly in oligotrophic oceans where carbon export pathways are limited.

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", "date": "2025-11-27", "date_type": "published", "publication": "Nature Communications", "volume": "16", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "10681", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/a7fna-em358", "funders": { "items": [ { "grant_number": "42130401" }, { "grant_number": "42141002" }, { "grant_number": "42421004" }, { "grant_number": "202306310164" }, { "grant_number": "-" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41467-025-65710-2", "pmcid": "PMC12660330", "primary_object": { "basename": "s41467-025-65710-2.pdf", "url": "https://authors.library.caltech.edu/records/a7fna-em358/files/s41467-025-65710-2.pdf" }, "related_objects": [ { "basename": "41467_2025_65710_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/a7fna-em358/files/41467_2025_65710_MOESM1_ESM.pdf" } ], "pub_year": "2025", "author_list": "Xu, Chao; Cassar, Nicolas; et al." }, { "id": "https://authors.library.caltech.edu/records/s13sy-cbz83", "eprint_status": "archive", "datestamp": "2025-07-07 21:24:51", "lastmod": "2025-07-07 21:24:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Taeho", "name": { "family": "Kim", "given": "Taeho" }, "orcid": "0000-0002-2560-7728" }, { "name": { "family": "Guti\u00e9rrez-Oribio", "given": "Diego" } }, { "name": { "family": "Stefanou", "given": "Ioannis" }, "orcid": "0000-0002-4552-7717" }, { "id": "Acosta-Mateo", "name": { "family": "Acosta", "given": "Mateo" }, "orcid": "0000-0002-0098-7912" }, { "id": "Avouac-J-P", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" } ] }, "title": "Single-well based control and optimization of hydraulic stimulation and induced seismicity: Application to the Otaniemi geothermal project", "ispublished": "pub", "full_text_status": "public", "keywords": "Induced seismicity; Control theory; Physics-based modeling", "note": "

© 2025 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

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The authors D.G.-O. and I.S. would like to acknowledge the European Research Council’s (ERC) support under the European Union’s Horizon 2020 research and innovation program (Grant agreement no. 101087771 INJECT) and the Region Pays de la Loire and Nantes Métropole under the Connect Talent programme (CEEV: Controlling Extreme EVents - Blast: Blas LoAds on STructures). T.K, J-P.A and M.A acknowledge funding from the NSF/Industry-University Collaborative Research Center ‘Geomechanics and Mitigation of Geohazards’ (National Science Foundation, United States award No. 1822214). M.A. acknowledges funding from the Swiss National Science Foundation, Switzerland through Grant P2ELP2_195127. M.A and J-P.A acknowledge funding from the Resnick sustainability institute at Caltech . The authors thank Prof. Ilmo Kukkonen and the anonymous reviewer for their valuable edits and comments that significantly improved the manuscript.
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", "abstract": "In this study, we apply control theory to mitigate earthquake hazards to a stress-based model of enhanced geothermal stimulation. The model considers pore pressure diffusion as the main stressing mechanism and rate-and-state friction as the shear failure mechanism. The controller is designed to follow a given average pressure and the probability of exceedance of a red-light earthquake (the magnitude at which the stimulation would have to stop by regulation) within chosen volumes surrounding the injection source and within a target time. We rigorously prove that the proposed controller can effectively force two output types within the system to given references, despite the presence of model uncertainties, and with minimal system information, using a continuous control signal. This framework is applied to a validated model of the 2018 Otaniemi geothermal stimulation. We use a suite of simulations to identify injection scenarios that outperform the 2018 Otaniemi stimulation. The optimal stimulation achieves higher average pressure in a shorter time with lower seismic hazard. The controller can help determine whether a combination of safety thresholds and optimization targets is feasible and economical. The control framework could be used to design stimulation schedules for enhanced geothermal systems.", "date": "2025-11", "date_type": "published", "publication": "Geothermics", "volume": "132", "publisher": "Elsevier", "pagerange": "103396", "issn": "0375-6505", "official_url": "https://authors.library.caltech.edu/records/s13sy-cbz83", "funders": { "items": [ {}, { "grant_number": "101087771" }, { "grant_number": "-" }, { "grant_number": "RISE-1822214" }, { "grant_number": "P2ELP2_195127" }, {} ] }, "local_group": { "items": [ { "id": "Center-for-Geomechanics-and-Mitigation-of-Geohazards-(GMG)" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.geothermics.2025.103396", "primary_object": { "basename": "1-s2.0-S0375650525001476-main.pdf", "url": "https://authors.library.caltech.edu/records/s13sy-cbz83/files/1-s2.0-S0375650525001476-main.pdf" }, "pub_year": "2025", "author_list": "Kim, Taeho; Guti\u00e9rrez-Oribio, Diego; et al." }, { "id": "https://authors.library.caltech.edu/records/m0geq-d5p65", "eprint_status": "archive", "datestamp": "2025-09-06 04:13:43", "lastmod": "2025-09-06 04:13:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bilir-T-Eren", "name": { "family": "Bilir", "given": "T. Eren" }, "orcid": "0000-0001-9465-9313" }, { "id": "Bloom-A-Anthony", "name": { "family": "Bloom", "given": "A. Anthony" }, "orcid": "0000-0002-1486-1499" }, { "name": { "family": "Konings", "given": "Alexandra G." }, "orcid": "0000-0002-2810-1722" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Parazoo-Nicholas-C", "name": { "family": "Parazoo", "given": "Nicholas C." }, "orcid": "0000-0002-4424-7780" }, { "name": { "family": "Quetin", "given": "Gregory R." }, "orcid": "0000-0002-7884-5332" }, { "name": { "family": "Norton", "given": "Alexander J." } }, { "name": { "family": "Worden", "given": "Matthew A." }, "orcid": "0009-0009-0414-4187" }, { "id": "Levine-Paul-A", "name": { "family": "Levine", "given": "Paul A." }, "orcid": "0000-0002-1248-6920" }, { "id": "Ma-Shuang", "name": { "family": "Ma", "given": "Shuang" }, "orcid": "0000-0002-6494-724X" }, { "id": "Braghiere-Renato-K", "name": { "family": "Braghiere", "given": "Renato K." }, "orcid": "0000-0002-7722-717X" }, { "name": { "family": "Longo", "given": "Marcos" }, "orcid": "0000-0001-5062-6245" }, { "id": "Bowman-Kevin", "name": { "family": "Bowman", "given": "Kevin" }, "orcid": "0000-0002-8659-1117" }, { "id": "Saatchi-Sassan", "name": { "family": "Saatchi", "given": "Sassan" }, "orcid": "0000-0001-8524-4917" }, { "id": "Schimel-David-S", "name": { "family": "Schimel", "given": "David S." }, "orcid": "0000-0003-3473-8065" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "name": { "family": "O'Sullivan", "given": "Michael" }, "orcid": "0000-0002-6278-3392" }, { "name": { "family": "Kang", "given": "Yanghui" }, "orcid": "0000-0001-8563-1503" }, { "id": "Pandey-Sudhanshu", "name": { "family": "Pandey", "given": "Sudhanshu" }, "orcid": "0000-0001-5938-385X" }, { "id": "Patton-Alex-J", "name": { "family": "Patton", "given": "Alex J." } }, { "id": "Yang-Yan", "name": { "family": "Yang", "given": "Yan" } }, { "name": { "family": "Liu", "given": "Yanlan" }, "orcid": "0000-0001-5129-6284" } ] }, "title": "Satellite-Constrained Reanalysis Reveals CO\u2082 Versus Climate Process Compensation Across the Global Land Carbon Sink", "ispublished": "pub", "full_text_status": "public", "keywords": "land carbon sink; data assimilation; remote sensing; terrestrial biosphere modeling; CO2 fertilization; climate change", "note": "

© 2025 Jet Propulsion Laboratory, California Institute of Technology and The Author(s). Government sponsorship acknowledged.

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This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

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The authors acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing the High Performance Computing resources used in this analysis; these resources were accessed through funding and support from the Jet Propulsion Laboratory Information and Technology Solutions Directorate. We thank the editor, Dr. Sharon Billings, and three anonymous reviewers for their constructive comments, which improved the quality of this work.

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This work was supported by three NASA 2020 Earth Sciences Grants (NNH20ZDA001N-CARBON, NNH22ZDA001N-CMS, NNH20ZDA001N-CMS). MAW was supported by NASA FINESST Grant 80NSSC21K1593. AGK was also supported by the Alfred P. Sloan foundation and by NSF DEB project 1942133. YK acknowledges support from NASA Grant 80NSSC24K1562. RKB acknowledges support from the Resnick Sustainability Institute. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).

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The specific CARDAMOM code version used in this work can be found on the open source CARDAMOM github repository at https://github.com/CARDAMOM-framework/CARDAMOM/tree/b8f1fd648ba9d7b6a42f249af6663fb757daf089. This code has also been placed on a zenodo repository (Bilir, 2025), along with the model output, and files to run both the parameter inversion and the forward model. Additional model documentation and user resources can be found at the CARDAMOM manual page, https://cardamom-framework.github.io/CARDAMOM/ (Levine et al., 2024).

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Supporting Information S1 (PDF)

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Original Version of Manuscript (PDF)

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Peer Review History (PDF)

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Author Response to Peer Review Comments (PDF)

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First Revision of Manuscript (PDF)

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Second Revision of Manuscript [Accepted] (PDF)

", "abstract": "

Terrestrial ecosystems annually absorb ~30% of anthropogenic C emissions. The degrees to which contemporary CO\u2082 and climate trends drive this absorption are uncertain, as are the governing mechanisms. To reduce uncertainty, we use Bayesian model-data integration (CARbon DAta MOdel fraMework) to retrieve a terrestrial biosphere reanalysis where Earth Observations optimally inform mechanistic model processes: observations include satellite- and inventory-based constraints on distributions and change in terrestrial C (including live biomass, dead organic C, and land-atmosphere CO\u2082 exchanges) and underlying mechanisms (including photosynthesis, deforestation, water storage anomalies, and fire). We find that the impact of 2001–2021's atmospheric CO\u2082 increase on terrestrial C (+39.4 PgC) opposes and far outweighs the impact of climate trends over this period (10.5 PgC). Globally, C gains are mostly attributable to live biomass growth (+31.2 PgC), while CO\u2082-induced dead organic C gains (+7.8 PgC) are compensated by climate-induced losses (8.8 PgC). The distribution of compensating dead C changes induces an aggregate shift in dead C from high- and mid-latitudes (3.5 PgC) to tropical ecosystems (+2.6 PgC). We additionally find global residence time reductions attributable to CO\u2082 (2.6%) and climate (1.3%) reflected across latitudes, irrespective of reservoir C changes. In aggregate, these changes reveal an acceleration and redistribution of terrestrial C stores in response to CO\u2082 and climate trends, which together reflect a gradual but fundamental reorganization of the terrestrial C cycle. Tracking this reorganization—through robust and continual diagnosis of ecosystem function—is essential for accurately resolving the compensating dynamics governing the strength and resilience of the terrestrial C sink.

", "date": "2025-10", "date_type": "published", "publication": "AGU Advances", "volume": "6", "number": "5", "publisher": "American Geophysical Union", "pagerange": "e2025AV001689", "issn": "2576-604X", "official_url": "https://authors.library.caltech.edu/records/m0geq-d5p65", "funders": { "items": [ { "grant_number": "NNH20ZDA001N\u2010CARBON" }, { "grant_number": "NNH22ZDA001N\u2010CMS" }, { "grant_number": "NNH20ZDA001N\u2010CMS" }, { "grant_number": "80NSSC21K1593" }, {}, { "grant_number": "1942133" }, { "grant_number": "80NSSC24K1562" }, { "grant_number": "80NM0018D0004" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2025av001689", "primary_object": { "basename": "AGU Advances - 2025 - Bilir - Satellite\u2010Constrained Reanalysis Reveals CO2 Versus Climate Process Compensation Across the.pdf", "url": "https://authors.library.caltech.edu/records/m0geq-d5p65/files/AGU Advances - 2025 - Bilir - Satellite\u2010Constrained Reanalysis Reveals CO2 Versus Climate Process Compensation Across the.pdf" }, "related_objects": [ { "basename": "2025av001689-sup-0001-supporting information si-s01.pdf", "url": "https://authors.library.caltech.edu/records/m0geq-d5p65/files/2025av001689-sup-0001-supporting information si-s01.pdf" } ], "pub_year": "2025", "author_list": "Bilir, T. Eren; Bloom, A. Anthony; et al." }, { "id": "https://authors.library.caltech.edu/records/6b7n0-vps70", "eprint_status": "archive", "datestamp": "2026-02-18 21:04:55", "lastmod": "2026-02-18 21:04:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johansen-Christian-M", "name": { "family": "Johansen", "given": "Christian M." }, "orcid": "0000-0003-0066-4424" }, { "id": "Benazzi-Elisabetta", "name": { "family": "Benazzi", "given": "Elisabetta" }, "orcid": "0000-0001-6756-3842" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "On the mechanism of photodriven hydrogenations of N\u2082 and other substrates by Hantzsch ester: Buffer is key to reactive H-atom donors", "ispublished": "pub", "full_text_status": "public", "keywords": "inorganic photochemistry; nitrogen fixation; photocatalysis", "note": "

© 2025 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).

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We thank the NIH (R35GM153322) for funding this work and the Resnick Sustainability Institute at Caltech for support of enabling facilities. We acknowledge the Dow Next Generation Educator Fund and Instrumentation Grants for support of the NMR and EPR facilities at Caltech. The Beckman Institute Laser Resource Center and J.R. Winkler are acknowledged for providing support with photophysical experiments. E.B. acknowledges funding from the European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie Grant Agreement 894986. C.M.J. is grateful for support from the Aker Scholarship Foundation. We are grateful to Dr. Hoimin Jung and Dr. Lucie Nurdin for providing synthetic materials used in this study and to Robert Anderson for help with GC-MS measurements.
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C.M.J. and J.C.P. designed research; C.M.J. and E.B. performed research; C.M.J. and J.C.P. analyzed data; and C.M.J. and J.C.P. wrote the paper.

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Appendix 01 (PDF).

", "abstract": "
The Hantzsch ester (HEH2) has found considerable utility as a photoreductant in synthesis, with photodriven transfer hydrogenation reactions typically limited to activated substrates. We recently established that the addition of an organic buffer of collidinium triflate [(ColH)OTf] and collidine (Col) allows photodriven transfer hydrogenation from HEH2 to N2 forming NH3 (nitrogen reduction; N2R) in the presence of a Mo catalyst. Given the requirements for Mo-catalyzed thermally driven N2R, this result suggested the generation of a significant driving force for proton-coupled electron transfer (PCET) when irradiating HEH2 in the presence of Col-buffer. In this study, we probe how Col-buffer enables efficient photodriven proton-coupled reductions with HEH2. Wavelength-dependent NH3 yields are consistent with HEH2 photoexcitation, and the combination of HEH2 with Col-buffer is privileged. Data are presented, suggesting that HEH2 is statically quenched via ET to [ColH]OTf through an H-bonded association complex to release ColH• and [HEH2]•+. Transient absorbance data and EPR studies establish that the resulting [HEH2]•+ intermediate is rapidly deprotonated by Col to yield HEH•, in net furnishing HEH• and ColH• as potent H-atom donors. Broader utility of this reagent combination is demonstrated in the photoreduction of a range of C=O and N=O π-bonds by HEH2, with a significant boost in rates and yield, and altered reactivity, observed on addition of Col-buffer. ColH• is posited as the most potent PCET donor generated (BDFEN−H of 28 kcal mol−1).
", "date": "2025-07-01", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "122", "number": "26", "publisher": "National Academy of Sciences", "pagerange": "e2502484122", "issn": "0027-8424", "official_url": "https://authors.library.caltech.edu/records/6b7n0-vps70", "funders": { "items": [ { "grant_number": "R35GM153322" }, { "grant_number": "894986" } ] }, "local_group": { "items": [ { "id": "Division-of-Chemistry-and-Chemical-Engineering" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2502484122", "pmcid": "PMC12232680", "primary_object": { "basename": "johansen-et-al-2025-on-the-mechanism-of-photodriven-hydrogenations-of-n2-and-other-substrates-by-hantzsch-ester-buffer.pdf", "url": "https://authors.library.caltech.edu/records/6b7n0-vps70/files/johansen-et-al-2025-on-the-mechanism-of-photodriven-hydrogenations-of-n2-and-other-substrates-by-hantzsch-ester-buffer.pdf" }, "related_objects": [ { "basename": "pnas.2502484122.sapp.pdf", "url": "https://authors.library.caltech.edu/records/6b7n0-vps70/files/pnas.2502484122.sapp.pdf" } ], "pub_year": "2025", "author_list": "Johansen, Christian M.; Benazzi, Elisabetta; et al." }, { "id": "https://authors.library.caltech.edu/records/2p7vy-b4x13", "eprint_status": "archive", "datestamp": "2025-12-03 22:42:39", "lastmod": "2025-12-03 22:42:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Charbonneau-Andrew", "name": { "family": "Charbonneau", "given": "Andrew" } }, { "id": "Deck-Katherine", "name": { "family": "Deck", "given": "Katherine" } }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "A Physics-Constrained Neural Differential Equation Framework for Data-Driven Snowpack Simulation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Snowpack; Climate prediction; Seasonal forecasting; Neural networks; Parameterization; Deep learning", "note": "

© 2025 American Meteorological Society. This published article is licensed under the terms of the default AMS reuse license. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy.

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We thank Marie Dumont for insightful discourse on process-based snow models, the SNOTEL effort, and the Kühtai, Col de Porte, Reynolds Mountain East, Sodankyla, Rofental, and Yala Basecamp teams for their data. A. C. was supported by the AI4Science initiative at the California Institute for Technology and a Department of Defense National Defense Science and Engineering Graduate (NDSEG) Fellowship. This work was generously supported by Schmidt Sciences, L.L.C., and the Resnick Sustainability Institute. The authors thank Jeffrey Coyle, Jaz Ammon, Joseph Kral, Matt Warbritton, and Daniel Tappa for help in verifying SNOTEL sensor placement and Yuan-Heng Wang for sharing calibrated Snow17 parameters.

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The SNOTEL data utilized in this study were available via the National Water and Climate Center, which lies under the United States Department of Agriculture. Data reports of the SNOTEL data were generated using the online portal found at https://www.nrcs.usda.gov/wps/portal/wcc/home/. The data from Col de Porte (Lejeune et al. 2019) can be found at the Observatoire des Sciences de l’Univers de Grenoble DOI portal at https://doi.osug.fr/public/CRYOBSCLIM_CDP/CRYOBSCLIM.CDP.2018.html, and data from Kühtai (Kraj\u010di et al. 2017) can be found as the supplemental material from https://doi.org/10.1002/2017WR020445. Raw data from Sodankyla (Essery et al. 2016) can be found from the Intensive Observation (sensors 8, 11) data portal at https://litdb.fmi.fi/ioa.php and automated weather station (sensor 15, portal at https://litdb.fmi.fi/luo0015_data.php). Reynolds Mountain East (Reba et al. 2011) data were obtained from an ESM-SnowMIP repository https://www.geos.ed.ac.uk/∼ressery/ESM-SnowMIP.html. Raw Yala Basecamp (Stigter et al. 2021; Shea et al. 2015) data were retrieved from https://rds.icimod.org/Home/DataDetail?metadataId=26859 and https://rds.icimod.org/Home/DataDetail?metadataId=1972554. Rofental (Warscher et al. 2024) data were retrieved from https://datapub.gfz-potsdam.de/download/10.5880.FIDGEO.2023.037-MNveB/. The data in this study were processed from these sources. Code for scraping and cleaning SNOTEL data and tutorials for data retrieval and training/modifying the neural models are available at https://clima.github.io/ClimaLand.jl/dev/generated/standalone/Snow/base_tutorial/. CSVs of the training/testing data are also available here, as a quality-controlled fully observational dataset of physical variables for calibration and ML applications.

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", "abstract": "

This paper presents a physics-constrained neural differential equation framework for parameterization and employs it to model the time evolution of seasonal snow depth given hydrometeorological forcings. When trained on data from multiple SNOTEL sites, the parameterization predicts daily snow depth with under 9% median error and Nash–Sutcliffe efficiencies over 0.94 across a wide variety of snow climates. The parameterization also generalizes to new sites not seen during training, which is not often true for calibrated snow models. Requiring the parameterization to predict snow water equivalent in addition to snow depth only increases the error to ∼12%. The structure of the approach guarantees the satisfaction of physical constraints, enables these constraints during model training, and allows modeling at different temporal resolutions without additional retraining of the parameterization. These benefits hold potential in climate modeling and could extend to other dynamical systems with physical constraints.

", "date": "2025-07", "date_type": "published", "publication": "Artificial Intelligence for the Earth Systems", "volume": "4", "number": "3", "publisher": "American Meteorological Society", "pagerange": "e240040", "issn": "2769-7525", "official_url": "https://authors.library.caltech.edu/records/2p7vy-b4x13", "funders": { "items": [ { "grant_number": "-" }, { "grant_number": "-" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/aies-d-24-0040.1", "primary_object": { "basename": "aies-AIES-D-24-0040.1.pdf", "url": "https://authors.library.caltech.edu/records/2p7vy-b4x13/files/aies-AIES-D-24-0040.1.pdf" }, "pub_year": "2025", "author_list": "Charbonneau, Andrew; Deck, Katherine; et al." }, { "id": "https://authors.library.caltech.edu/records/qt9em-c6d98", "eprint_status": "archive", "datestamp": "2025-07-22 16:04:54", "lastmod": "2025-07-22 16:04:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Calvello-Edoardo", "name": { "family": "Calvello", "given": "Edoardo" }, "orcid": "0009-0002-6722-823X" }, { "name": { "family": "Reich", "given": "Sebastian" }, "orcid": "0000-0002-5336-8904" }, { "id": "Stuart-A-M", "name": { "family": "Stuart", "given": "Andrew M." }, "orcid": "0000-0001-9091-7266" } ] }, "title": "Ensemble Kalman methods: A mean-field perspective", "ispublished": "pub", "full_text_status": "public", "note": "

© The Author(s), 2025. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.

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The authors are grateful to Dmitry Burov for helpful advice regarding the numerical experiments; they are also grateful to Arnaud Vadeboncoeur, Eviatar Bach, Ricardo Baptista and Daniel Sanz-Alonso for helpful discussions which improved this paper. The authors thank Mark Asch for careful reading of the paper, and useful feedback. Finally AMS is grateful for hospitality offered at the University of Chicago, by Guillaume Bal, Peter McCullagh, Daniel Sanz-Alonso and Rebecca Willett, where he delivered lectures based on a preliminary version of this paper in May 2022.

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EC is grateful to the Kortschak Scholars Program within the CMS Department at Caltech for financial support. Thework ofSRis supported by Deutsche Forschungsgemeinschaft (DFG) – Project-ID 318763901 – SFB1294. The work of AMS is supported by NSF award AGS1835860, and by a Department of Defense Vannevar Bush Faculty Fellowship, which also supports EC. In addition, AMS and EC are supported by the SciAI Center, funded by the Office of Naval Research (ONR), under grant no. N00014-23-1-2729. The work of EC was also supported by the Resnick Sustainability Institute.

", "abstract": "Ensemble Kalman methods, introduced in 1994 in the context of ocean state estimation, are now widely used for state estimation and parameter estimation (inverse problems) in many arenae. Their success stems from the fact that they take an underlying computational model as a black box to provide a systematic, derivative-free methodology for incorporating observations; furthermore the ensemble approach allows for sensitivities and uncertainties to be calculated. Analysis of the accuracy of ensemble Kalman methods, especially in terms of uncertainty quantification, is lagging behind empirical success; this paper provides a unifying mean-field-based framework for their analysis. Both state estimation and parameter estimation problems are considered, and formulations in both discrete and continuous time are employed. For state estimation problems, both the control and filtering approaches are considered; analogously for parameter estimation problems, the optimization and Bayesian perspectives are both studied. As well as providing an elegant framework, the mean-field perspective also allows for the derivation of a variety of methods used in practice. In addition it unifies a wide-ranging literature in the field and suggests open problems.", "date": "2025-07", "date_type": "published", "publication": "Acta Numerica", "volume": "34", "number": "7", "publisher": "Cambridge University Press (CUP)", "pagerange": "123-291", "issn": "0962-4929", "official_url": "https://authors.library.caltech.edu/records/qt9em-c6d98", "funders": { "items": [ { "grant_number": "-" }, { "grant_number": "318763901 \u2013 SFB1294" }, { "grant_number": "AGS-1835860" }, { "grant_number": "-" }, { "grant_number": "N00014-23-1-2729" }, {} ] }, "local_group": { "items": [ { "id": "Division-of-Engineering-and-Applied-Science" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1017/s0962492924000060", "primary_object": { "basename": "ensemble-kalman-methods-a-mean-field-perspective.pdf", "url": "https://authors.library.caltech.edu/records/qt9em-c6d98/files/ensemble-kalman-methods-a-mean-field-perspective.pdf" }, "pub_year": "2025", "author_list": "Calvello, Edoardo; Reich, Sebastian; et al." }, { "id": "https://authors.library.caltech.edu/records/5p6p9-m5y27", "eprint_status": "archive", "datestamp": "2025-06-06 15:15:06", "lastmod": "2025-06-06 15:15:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Acosta-Mateo", "name": { "family": "Acosta", "given": "Mateo" }, "orcid": "0000-0002-0098-7912" }, { "id": "Ledevin-Thomas", "name": { "family": "Ledevin", "given": "Thomas" } }, { "id": "Salha-Guillaume", "name": { "family": "Salha", "given": "Guillaume" }, "orcid": "0009-0002-6231-4251" }, { "id": "Forestier-Charles", "name": { "family": "Forestier", "given": "Charles" } }, { "id": "Michelin-Lucie", "name": { "family": "Michelin", "given": "Lucie" } }, { "id": "Fu-Xiaojing-Ruby", "name": { "family": "Fu", "given": "Xiaojing" }, "orcid": "0000-0001-7120-704X" }, { "id": "Avouac-Jean-Philippe", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" } ] }, "title": "Flow2Quake, an integrated multiphase flow, geomechanical and seismicity model for efficient forecasting of injection and extraction induced earthquakes", "ispublished": "pub", "full_text_status": "public", "keywords": "Reduced order model; Carbon capture and storage; Multiphase vertical flow equilibrium; Gas injection/extraction; Geomechanical modeling; Induced seismicity; Decatur; Groningen", "note": "

© 2025 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

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This study was supported by the NSF/IUCRC Geomechanics and Mitigation of Geohazards (National Science Foundation, USA award # 1822214). T.L. acknowledges École Polytechnique, FR for its financing support through the Chaire Energies Durables. M.A. Acknowledges funding from the Swiss National Science Foundation through grant P2ELP2195127 and from Caltech’s Resnick sustainability institute, USA. We gratefully acknowledge data and support from Shell Global Solutions, USA . We gratefully acknowledge discussions with Guanli Wang and Adrian Moure. Authors declare that they have no competing interests.
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All data and codes can be found in: doi: 10.17605/OSF.IO/WSH32.

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MMC S1. The appendix contains information on (A) Fluid properties (B) The multiphase flow model derivation (C) Benchmarking of the MP-Flow model (PDF)

", "abstract": "

Efforts to secure and decarbonize the energy sector are driving various subsurface reservoir operations. These operations carry a risk of inducing surface deformation and earthquakes. To assess these risks, modeling tools integrating fluid flow, geomechanical and seismicity modeling are needed. Here, we demonstrate the use of an efficient Vertical Flow Equilibrium (VFE) multiphase fluid flow model in an integrated framework for deformation and seismicity modeling both under fluid extraction or injection configurations. The VFE-computed spatio-temporal pressure evolution is fed to a geomechanical module to compute surface deformation and stress changes in and around the reservoir. Stress changes feed a seismicity module to calculate earthquake probabilities. First, we apply the benchmarked model to gas extraction from Groningen. There, we can reduce the variance of pressure measurements by ∼38% with respect to a pre-existing single phase flow model while remaining computationally efficient. The surface deformation and seismicity simulations show remarkable agreement with observed data. Second, we study induced seismicity due to CO\u2082 sequestration in the Decatur phase 1 project. We find that, for the Decatur phase 1 project, poroelastic stress changes can account for most of the non-clustered observed seismicity within modeling uncertainties. Finally we simulate scenarios for CO\u2082 sequestration using the Quest field. The sloping reservoir topography significantly impacts the predicted position of the CO\u2082 plume but the effects on geomechanical deformation (and seismicity) are minimal. Incorporating VFE models with geomechanical and seismicity forecasts with real-world case applications can allow real-time hazard assessment and mitigation procedures.

", "date": "2025-07", "date_type": "published", "publication": "International Journal of Greenhouse Gas Control", "volume": "145", "publisher": "Elsevier", "pagerange": "104388", "issn": "1750-5836", "official_url": "https://authors.library.caltech.edu/records/5p6p9-m5y27", "funders": { "items": [ { "grant_number": "EAR-1822214" }, {}, { "grant_number": "P2ELP2195127" }, {} ] }, "local_group": { "items": [ { "id": "Center-for-Geomechanics-and-Mitigation-of-Geohazards-(GMG)" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" }, { "id": "Division-of-Engineering-and-Applied-Science" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.ijggc.2025.104388", "primary_object": { "basename": "1-s2.0-S1750583625000866-main.pdf", "url": "https://authors.library.caltech.edu/records/5p6p9-m5y27/files/1-s2.0-S1750583625000866-main.pdf" }, "related_objects": [ { "basename": "1-s2.0-S1750583625000866-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/5p6p9-m5y27/files/1-s2.0-S1750583625000866-mmc1.pdf" } ], "pub_year": "2025", "author_list": "Acosta, Mateo; Ledevin, Thomas; et al." }, { "id": "https://authors.library.caltech.edu/records/9m24h-e5211", "eprint_status": "archive", "datestamp": "2025-10-16 00:44:17", "lastmod": "2025-10-16 00:44:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Magistro-Beatrice", "name": { "family": "Magistro", "given": "Beatrice" }, "orcid": "0000-0001-7423-3577" }, { "id": "Debnath-Ramit", "name": { "family": "Debnath", "given": "Ramit" }, "orcid": "0000-0003-0727-5683" }, { "name": { "family": "Ebanks", "given": "Danny" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. Michael" }, "orcid": "0000-0002-8113-4451" } ] }, "title": "Political ideology and views toward solar geoengineering in the United States", "ispublished": "pub", "full_text_status": "public", "note": "

© 2025 Magistro et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

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RMA and BM's work is supported by Caltech’s Resnick Sustainability Institute. DE's work on this project was originally supported by Caltech's Resnick Sustainability Institute while he was a PhD Candidate at Caltech. RD's work is supported by the Cambridge Arts, Humanities and Social Science (AHSS) Grants and the Bill \\& Melinda French Gates Foundation (OPP1144).

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Data availability statement: All codes and data needed for replication of this study can be found here: https://github.com/rmichaelalvarez/pol_ideology_solar_geoengineering.

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S1 File. Political Ideology: respondents self-identified political belief. Gender: respondents self-identified gender as man, woman or others. Education: respondent’s self-reported education level. Subjective Income: respondents self-reported financial status. Religion: respondents self-reported religious belief. Environmental knowledge: respondents self-reported weather and climate knowledge.

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Peer Review History: PLOS recognizes the benefits of transparency in the peer review
process; therefore, we enable the publication of all of the content of peer review and
author responses alongside final, published articles. The editorial history of this article is available here: https://doi.org/10.1371/journal.pclm.0000643

", "abstract": "Political polarization remains a significant barrier to effective climate action in the United States. Conservatives often express skepticism toward climate change policies emphasizing government intervention, while liberals are generally more supportive of these efforts. Solar geoengineering (SG), an emerging technology proposed to cool the Earth's atmosphere, offers a climate intervention that may transcend entrenched ideological divides. SG remains relatively unknown to the public and has not yet been widely framed in partisan terms. Moreover, its perceived nature as a technological solution could appeal to conservatives resistant to traditional climate measures. This study investigates the relationship between political ideology and public attitudes toward SG, conditional on respondents' familiarity with the technology. Using a nationally representative sample of 2,109 American voters and applying linear probability and multinomial logistic regression models, we find that greater familiarity with SG is associated with reduced political polarization regarding SG's perceived effectiveness, associated risks, and preferred climate strategies. Our findings suggest that increasing public awareness of SG could foster bipartisan engagement with climate policy, helping bridge the ideological divide.", "date": "2025-06-26", "date_type": "published", "publication": "PLOS Climate", "volume": "4", "number": "6", "publisher": "PLOS", "pagerange": "e0000643", "issn": "2767-3200", "editors": { "items": [ { "name": { "family": "Hsueh", "given": "Lily" } } ] }, "official_url": "https://authors.library.caltech.edu/records/9m24h-e5211", "funders": { "items": [ {}, {}, { "grant_number": "OPP1144" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-the-Humanities-and-Social-Sciences" } ] }, "doi": "10.1371/journal.pclm.0000643", "primary_object": { "basename": "journal.pclm.0000643.pdf", "url": "https://authors.library.caltech.edu/records/9m24h-e5211/files/journal.pclm.0000643.pdf" }, "related_objects": [ { "basename": "pclm.0000643.s001.pdf", "url": "https://authors.library.caltech.edu/records/9m24h-e5211/files/pclm.0000643.s001.pdf" } ], "pub_year": "2025", "author_list": "Magistro, Beatrice; Debnath, Ramit; et al." }, { "id": "https://authors.library.caltech.edu/records/jtepk-kwf05", "eprint_status": "archive", "datestamp": "2025-07-01 21:46:44", "lastmod": "2025-07-01 21:46:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Wen-Yuan", "name": { "family": "Liu", "given": "Wen-Yuan" }, "orcid": "0000-0002-2003-8589" }, { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Peng-Ruojing", "name": { "family": "Peng", "given": "Ruojing" }, "orcid": "0000-0002-5293-7503" }, { "name": { "family": "Gu", "given": "Zheng-Cheng" } }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Accurate Simulation of the Hubbard Model with Finite Fermionic Projected Entangled Pair States", "ispublished": "pub", "full_text_status": "public", "keywords": "Quantum simulation; Hubbard model; Projected entangled pair states; Tensor network methods; Tensor network renormalization", "note": "

© 2025 American Physical Society.

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This work was primarily supported by the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Systems Accelerator. Additional support for H. Z. (DMRG calculations) was provided by U.S. Air force Office of Scientitic Research under Grant No. AFOSR-FA9550-18-1-0095. G. K. C. acknowledges additional support from the Simons Investigator program. Z.-C. G. is supported by funding from Hong Kong’s Research Grants Council (CRF C7012-21GF and RGC Research Fellow Scheme 2023/24, No. RFS2324-4S02). W.-Y. L. also acknowledges additional support from a start-up grant from Zhejiang University for the final part of this work. The DMRG calculations in this work were performed using block2 [90-92], and the scripts can be found in Ref. [93]. The computations presented in this work were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.

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The data that support the findings of this Letter are openly available [94].

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The SM include a review of Grassmann tensor network representation, and additional numerical results for the Hubbard model.

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fpeps-hubbard-SM.pdf

", "abstract": "

We demonstrate the use of finite-size fermionic projected entangled pair states, in conjunction with variational Monte Carlo, to perform accurate simulations of the ground state of the 2D Hubbard model. Using bond dimensions of up to \ud835\udc37=28, we show that we can surpass state-of-the-art density matrix renormalization group energies that use up to \ud835\udc5a=32 000 SU(2) multiplets on eight-leg ladders. We further apply our methodology to 10 ×16, 12 ×16, and 16 ×16 lattices at 1/8 hole doping and observe the dimensional crossover between stripe orientations. Our Letter shows the power of finite-size fermionic tensor networks to resolve the physics of the 2D Hubbard model and related problems.

", "date": "2025-06-24", "date_type": "published", "publication": "Physical Review Letters", "volume": "134", "number": "25", "publisher": "American Physical Society", "pagerange": "256502", "issn": "0031-9007", "official_url": "https://authors.library.caltech.edu/records/jtepk-kwf05", "funders": { "items": [ {}, { "grant_number": "AFOSR-FA9550-18-1-0095" }, {}, { "grant_number": "CRF C7012-21GF" }, { "grant_number": "RFS2324-4S02" }, {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Chemistry-and-Chemical-Engineering" } ] }, "doi": "10.1103/r4q9-4yvj", "primary_object": { "basename": "r4q9-4yvj.pdf", "url": "https://authors.library.caltech.edu/records/jtepk-kwf05/files/r4q9-4yvj.pdf" }, "related_objects": [ { "basename": "fpeps-hubbard-SM.pdf", "url": "https://authors.library.caltech.edu/records/jtepk-kwf05/files/fpeps-hubbard-SM.pdf" } ], "pub_year": "2025", "author_list": "Liu, Wen-Yuan; Zhai, Huanchen; et al." }, { "id": "https://authors.library.caltech.edu/records/9h1c1-vtc89", "eprint_status": "archive", "datestamp": "2026-01-27 01:45:21", "lastmod": "2026-01-27 01:45:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Foster", "given": "Kelsey T." }, "orcid": "0000-0002-2471-7319" }, { "name": { "family": "Sun", "given": "Wu" }, "orcid": "0000-0002-2333-6282" }, { "name": { "family": "Merder", "given": "Julian" }, "orcid": "0000-0002-5958-7016" }, { "name": { "family": "Hararuk", "given": "Oleksandra" }, "orcid": "0000-0001-5694-6813" }, { "name": { "family": "Kurz", "given": "Werner A." }, "orcid": "0000-0003-4576-7849" }, { "name": { "family": "Malhotra", "given": "Avni" }, "orcid": "0000-0002-7850-6402" }, { "name": { "family": "Metsaranta", "given": "Juha" }, "orcid": "0000-0003-0450-3783" }, { "name": { "family": "Nesdoly", "given": "Andrea" }, "orcid": "0000-0001-8473-4228" }, { "name": { "family": "Sinha", "given": "Eva" }, "orcid": "0000-0003-0769-0166" }, { "name": { "family": "Bond\u2010Lamberty", "given": "Ben" }, "orcid": "0000-0001-9525-4633" }, { "name": { "family": "Huntzinger", "given": "Deborah" }, "orcid": "0000-0003-2998-099X" }, { "name": { "family": "Natali", "given": "Susan M." }, "orcid": "0000-0002-3010-2994" }, { "name": { "family": "Schwalm", "given": "Christopher" }, "orcid": "0000-0002-5035-5681" }, { "id": "Michalak-Anna-M", "name": { "family": "Michalak", "given": "Anna M." }, "orcid": "0000-0002-6152-7979" } ] }, "title": "Permafrost, Peatland, and Cropland Regions Are Key to Reconciling North American Carbon Sink Estimates", "ispublished": "pub", "full_text_status": "public", "keywords": "North America; carbon cycle; permafrost; peatlands; croplands", "note": "

© 2025. His Majesty the King in Right of Canada. Battelle Memorial Institute and The Author(s). Reproduced with the permission of the Minister of Energy and Natural Resources. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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K.T.F., W.S., A.M., B.B.-L., and A.M.M. acknowledge support from the NASA Terrestrial Ecology Program (Grant 80NSSC22K1253). K.T.F., W.S., and A.M.M. acknowledge support from the Carnegie Institution for Scienceendowment. We thank all modelers of the Trends in Net Land-Atmosphere Exchange project (TRENDY; https://blogs.exeter.ac.uk/trendy/). We thank the CarbonTracker2022 Team for the CarbonTracker CT2022 results provided by NOAA GML, Boulder, Colorado, USA from the website at http://carbontracker.noaa.gov. We thank the CarbonTracker-Lagrange team for terrestrial CO2 flux data. We thank the Atmospheric and Environmental Research, Inc. (AER)—particularly, Thomas Nehrkorn, John Henderson, and Janusz Eluszkiewicz—for conducting WRF-STILT simulations and providing transport footprints. We thank the CarbonTracker-Lagrange project team for proving the WRF-STILT transport footprints. The ESA CCI LC data used here contain modified Copernicus Climate Change Service information [2024]. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains. Computations presented in this study were conducted through the Carnegie Institution for Science's partnership in the Resnick High Performance Computing Center (https://www.hpc.caltech.edu), a facility supported by Resnick Sustainability Institute at the California Institute of Technology.

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Terrestrial biosphere models from TRENDY-v11 were accessed through the Global Carbon Budget data hub (https://globalcarbonbudgetdata.org/; Friedlingstein et al., 2022; Sitch et al., 2015, 2024). Inversions from GCB 2022 were downloaded from https://hdl.handle.net/11676/GahdRITjT22GGmq_GCi4o_wy (Luijkx et al., 2023). CarbonTracker CT2022 results provided by NOAA GML, Boulder, Colorado, USA were accessed from the website at http://carbontracker.noaa.gov (Jacobson et al., 2023). CarbonTracker-Lagrange data were downloaded from https://gml.noaa.gov/ccgg/arc/?id=131 (L. Hu et al., 2019). The MIROC inversion data were downloaded from https://zenodo.org/records/5776197 (Patra, 2021). We downloaded WRF-STILT footprints from https://gml.noaa.gov/ccgg/carbontracker-lagrange/ (L. Hu et al., 2019). IGBP land cover classifications are available at Friedl et al., 2010. ESA CCI LC data is available at https://cds.climate.copernicus.eu/datasets/satellite-land-cover?tab=overview (CCCS, 2019). The NCSCD was downloaded from https://bolin.su.se/data/ncscd/. The ABCflux Database is available from Virkkala et al. (2021). CLM5 simulations from Lombardozzi et al. (2020) are made publicly available and were accessed at the UCAR/NCAR Climate Data Gateway (https://doi.org/10.5065/d6154fwh). Lastly, we used Canada's managed forests inventory-based estimate from the NFCMARS (https://publications.gc.ca/site/eng/9.506002/publication.html; ECCC, 2022).

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Supporting Information S1 (PDF)

", "abstract": "

Persistent discrepancies between bottom\u2010up, terrestrial biosphere models (TBMs), and top\u2010down, atmospheric inversions, have made it difficult to quantify the magnitude of the North American terrestrial carbon sink. Previous studies have compared aggregated continent\u2010scale estimates of carbon fluxes from TBMs and inversions for all of North America, but this provides limited insights into finer\u2010scale mismatches that contribute to the overall discrepancies. Here we evaluate agreement between TBM and inversion carbon flux estimates at 1° × 1° resolution to provide more direct insights into where models disagree and what underlying factors drive discrepancies. We find that the additional carbon uptake estimated by inversions, in just 16% of the area of North America, is large enough to account for the discrepancy between TBMs and inversions across the whole continent. The majority of these differences occur in permafrost, peatland, and cropland regions. In these regions, we find a higher likelihood of potential biases in the weaker sink estimates from TBMs, suggesting that the stronger sink implied by inversions is more likely to be realistic. However, the current observational coverage is insufficient for fully assessing the causes of discrepancies or the magnitude of biases in either approach. Encouragingly, improved representation of agricultural processes in a TBM led to better agreement with inversions in croplands. Efforts to accurately model cropland dynamics will help improve agreement between TBMs and inversions. Overall, this work presents a clear path for reconciling the discrepancies between inversion and TBM estimates of the North American carbon sink that have persisted for two decades.

", "date": "2025-06", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "39", "number": "6", "publisher": "American Geophysical Union", "pagerange": "e2024GB008460", "issn": "0886-6236", "official_url": "https://authors.library.caltech.edu/records/9h1c1-vtc89", "funders": { "items": [ { "grant_number": "80NSSC22K1253" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2024gb008460", "primary_object": { "basename": "Global Biogeochemical Cycles - 2025 - Foster - Permafrost Peatland and Cropland Regions Are Key to Reconciling North.pdf", "url": "https://authors.library.caltech.edu/records/9h1c1-vtc89/files/Global Biogeochemical Cycles - 2025 - Foster - Permafrost Peatland and Cropland Regions Are Key to Reconciling North.pdf" }, "related_objects": [ { "basename": "2024gb008460-sup-0001-supporting information si-s01.pdf", "url": "https://authors.library.caltech.edu/records/9h1c1-vtc89/files/2024gb008460-sup-0001-supporting information si-s01.pdf" } ], "pub_year": "2025", "author_list": "Foster, Kelsey T.; Sun, Wu; et al." }, { "id": "https://authors.library.caltech.edu/records/wz2n2-t4m23", "eprint_status": "archive", "datestamp": "2025-06-02 21:37:24", "lastmod": "2025-06-02 21:37:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Yujie", "name": { "family": "Wang", "given": "Yujie" }, "orcid": "0000-0002-3729-2743" }, { "id": "Braghiere-Renato-K", "name": { "family": "Braghiere", "given": "Renato K." }, "orcid": "0000-0002-7722-717X" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Yao-Yitong", "name": { "family": "Yao", "given": "Yitong" }, "orcid": "0000-0002-1713-6719" }, { "id": "Shen-Zhaoyi", "name": { "family": "Shen", "given": "Zhaoyi" }, "orcid": "0000-0002-0444-4720" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" }, { "id": "Bloom-A-Anthony", "name": { "family": "Bloom", "given": "A. Anthony" }, "orcid": "0000-0002-1486-1499" }, { "id": "Schimel-David", "name": { "family": "Schimel", "given": "David" }, "orcid": "0000-0003-3473-8065" }, { "name": { "family": "Croft", "given": "Holly" } }, { "name": { "family": "Winkler", "given": "Alexander J." }, "orcid": "0000-0001-6574-4471" }, { "name": { "family": "Reichstein", "given": "Markus" }, "orcid": "0000-0001-5736-1112" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Impacts of leaf traits on vegetation optical properties in Earth system modeling", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon cycle; Climate and Earth system modelling", "note": "

© The Author(s) 2025.

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This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.

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We gratefully acknowledge funding support from the University of Science and Technology of China (Award #KY2080000142, received by YW), the National Aeronautics and Space Administration (NASA) Carbon Cycle Science (Award #80NSSC21K1712, received by CF) and OCO2/3 Science Team (Award #80NSSC21K1075 and #80NSSC24K0761, received by CF). CF and TS acknowledge support from Schmidt Sciences, LLC. Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work was supported in part by the Resnick Sustainability Institute at Caltech. We would like to acknowledge high-performance computing support from the Derecho system (https://doi.org/10.5065/qx9a-pg09) provided by the NSF National Center for Atmospheric Research (NCAR), sponsored by the National Science Foundation.

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The CHL42 and LMA37,38 maps and benchmark datasets62,98 used in this study are available from GriddingMachine.jl94. Global scale LOP maps derived using CliMA Land, CESM modifications, and CESM model output are available at https://doi.org/10.5281/zenodo.757031490.

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The CliMA Land model used to simulate leaf hyperspectral reflectance and transmittance is available at https://github.com/CliMA/Land. All figures were generated using Python with the matplotlib and cartopy modules. The code for generating and analyzing the data can be found at https://doi.org/10.5281/zenodo.757031490.

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Supplementary Information

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Transparent Peer Review file

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", "abstract": "
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Quantifying surface energy and carbon budgets is essential for projecting Earth’s climate. Earth System Models (ESMs) typically simulate land surface processes based on plant functional types (PFTs), neglecting the diversity of plant functional traits or characteristics (PFCs; e.g., chlorophyll content and leaf mass per area). Here, we demonstrate substantial differences in modeled leaf optical properties (LOP) and surface albedo between traditional PFT-based and PFC-based approaches, particularly in tropical and boreal forests. We configure the canopy radiative transfer scheme in the Community Earth System Model using PFC-based LOP. This new configuration produces lower shortwave surface albedo in the tropics but higher albedo in boreal regions (>5 W m−2 radiative flux differences), and a weaker tropical but stronger boreal carbon sink. Through land-atmosphere coupling, the PFC-based configuration further alters atmospheric processes, leading to different temperature, cloud cover, and precipitation patterns. Our findings highlight the need to move beyond traditional PFT-based approaches in ESMs.

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", "date": "2025-05-29", "date_type": "published", "publication": "Nature Communications", "volume": "16", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "4968", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/wz2n2-t4m23", "funders": { "items": [ { "grant_number": "KY2080000142" }, { "grant_number": "80NSSC21K1712" }, { "grant_number": "80NSSC21K1075" }, { "grant_number": "80NSSC24K0761" }, {}, {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41467-025-60149-x", "pmcid": "PMC12119829", "primary_object": { "basename": "s41467-025-60149-x.pdf", "url": "https://authors.library.caltech.edu/records/wz2n2-t4m23/files/s41467-025-60149-x.pdf" }, "related_objects": [ { "basename": "41467_2025_60149_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/wz2n2-t4m23/files/41467_2025_60149_MOESM1_ESM.pdf" }, { "basename": "41467_2025_60149_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/wz2n2-t4m23/files/41467_2025_60149_MOESM2_ESM.pdf" } ], "pub_year": "2025", "author_list": "Wang, Yujie; Braghiere, Renato K.; et al." }, { "id": "https://authors.library.caltech.edu/records/3qtbf-x0x14", "eprint_status": "archive", "datestamp": "2025-05-26 18:42:12", "lastmod": "2025-05-26 18:42:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ward-Ryan-X", "name": { "family": "Ward", "given": "Ryan X." }, "orcid": "0000-0003-2317-3310" }, { "id": "Baliaka-Haroula-D", "name": { "family": "Baliaka", "given": "Haroula D." }, "orcid": "0000-0001-7851-8449" }, { "id": "Schulze-Benjamin-C", "name": { "family": "Schulze", "given": "Benjamin C." }, "orcid": "0000-0002-6405-8872" }, { "name": { "family": "Kerr", "given": "Gaige H." }, "orcid": "0000-0001-8869-0752" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Hasheminassab-Sina", "name": { "family": "Hasheminassab", "given": "Sina" } }, { "name": { "family": "Bahreini", "given": "Roya" }, "orcid": "0000-0001-8292-5338" }, { "name": { "family": "Dillner", "given": "Ann M." }, "orcid": "0000-0001-8306-754X" }, { "name": { "family": "Russell", "given": "Armistead" }, "orcid": "0000-0003-2027-8870" }, { "name": { "family": "Ng", "given": "Nga L." }, "orcid": "0000-0001-8460-4765" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "Richard C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Poorly quantified trends in ammonium nitrate remain critical to understand future urban aerosol control strategies", "ispublished": "pub", "full_text_status": "public", "note": "

© 2025 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).

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We thank H. Pye for useful discussions using the CMAQ Equates data, NOAA CSL for the HNO3 measurements during the RECAP campaign, CARB for the NH3 measurements during the RECAP campaign, and the Megacities project for meteorological data.
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R.X.W. acknowledges support from the Resnick Sustainability Institute Graduate Fellowship. H.D.B. acknowledges support from the Resnick Sustainability Institute and the Onassis Foundation - Scholarship ID: F ΖT 006-1/2023-2024. Funding for the ASCENT project is provided by the National Science Foundation (AGS-2131914). We thank NOAA (NA21OAR4310224) and the California Air Resources Board (21RD017 and 22RD015) for supporting observations and analysis of data obtained on the Caltech campus. Criteria air quality instrumentation at Caltech used in this analysis was supported by the Resnick Sustainability Institute and the Linde Center for Global Environmental Science.

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G.H.K. reports serving as a consultant for the Environmental Defense Fund, New York State Attorney General, Department of Justice, and California Air Resources Board. The authors declare that they have no other competing interests.

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Supplementary Text; Figs. S1 to S23; References (PDF)

", "abstract": "
Despite decades of progress in reducing nitrogen oxide (NOx) emissions, ammonium nitrate (AN) remains the primary inorganic component of particulate matter (PM) in Los Angeles (LA). Using aerosol mass spectrometry over multiple years in LA illustrates the controlling dynamics of AN and their evolution over the past decades. These data suggest that much of the nitric acid (HNO3) production required to produce AN in LA occurs during the nighttime via heterogeneous hydrolysis of N2O5. Further, we show that US Environmental Protection Agency–codified techniques for measuring total PM2.5 fail to quantify the AN component, while low-cost optical sensors demonstrate good agreement. While previous studies suggest that declining NOx has reduced AN, we show that HNO3 formation is still substantial and leads to the formation of many tens of micrograms per cubic meter of AN aerosol. Continued focus on reductions in NOx will help meet the PM2.5 standards in the LA basin and many other regions.
", "date": "2025-05-23", "date_type": "published", "publication": "Science Advances", "volume": "11", "number": "21", "publisher": "American Association for the Advancement of Science", "pagerange": "eadt8957", "issn": "2375-2548", "official_url": "https://authors.library.caltech.edu/records/3qtbf-x0x14", "funders": { "items": [ {}, { "grant_number": "F \u0396T 006-1/2023-2024" }, { "grant_number": "AGS-2131914" }, { "grant_number": "NA21OAR4310224" }, { "grant_number": "21RD017" }, { "grant_number": "22RD015" } ] }, "local_group": { "items": [ { "id": "Division-of-Chemistry-and-Chemical-Engineering" }, { "id": "Division-of-Engineering-and-Applied-Science" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.adt8957", "pmcid": "PMC12094242", "primary_object": { "basename": "sciadv.adt8957.pdf", "url": "https://authors.library.caltech.edu/records/3qtbf-x0x14/files/sciadv.adt8957.pdf" }, "related_objects": [ { "basename": "sciadv.adt8957_sm.pdf", "url": "https://authors.library.caltech.edu/records/3qtbf-x0x14/files/sciadv.adt8957_sm.pdf" } ], "pub_year": "2025", "author_list": "Ward, Ryan X.; Baliaka, Haroula D.; et al." }, { "id": "https://authors.library.caltech.edu/records/16htd-dqr46", "eprint_status": "archive", "datestamp": "2025-07-22 21:24:00", "lastmod": "2025-07-22 21:24:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nimlos-Danika", "name": { "family": "Nimlos", "given": "Danika" }, "orcid": "0000-0002-5414-0039" }, { "id": "Arellano-Alejandro", "name": { "family": "Arellano", "given": "Alejandro" } }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott Kevin" }, "orcid": "0000-0003-3538-2259" } ] }, "title": "Approaching the Lower Temporal Limit of Laser-Produced Plasma Sources for Table-Top Soft X-ray NEXAFS Measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "X-ray absorption spectroscopy; Time-resolved spectroscopy; Analytical methods; Laser-produced plasmas; Table-top X-ray sources", "note": "

© 2025 Wiley-VCH GmbH.

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This work was funded by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. This work was also funded by the Resnick Sustainability Institute and the Beckman Institute Pilot Program.

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", "abstract": "

The increasing popularity of time-resolved X-ray absorption measurements for understanding dynamics in molecular and material systems has led to many advances in table-top sources for pulsed X-rays. We report on a table-top laser-produced plasma (LPP) source that can perform soft X-ray (SXR), near-edge X-ray absorption fine structure (NEXAFS) measurements using a laser source with 23\u2005ps pulse duration. The spectrometer's key specifications, such as brilliance, resolution, and stability, are characterized against the more commonly used longer-pulse-duration LPP sources. The 23\u2005ps laser produced approximately an order of magnitude weaker SXR flux than the 8\u2005ns laser for a higher power density due to the smaller total energy absorbed by the plasma. The increased repetition rate, as well as the use of a high line-density X-grating, and a self-referencing scheme still allowed for NEXAFS measurements of Si3N4 and TiO2 thin films with 2.5\u2005minute acquisition times, a resolving power of E/ΔE=424, and a signal-to-noise ratio of 100. It was observed that degradation of the gas jet nozzle led to long-term instability of the source, which can be remediated using alternative nozzle designs. This work demonstrates the feasibility of achieving higher temporal resolution in future time-resolved X-ray absorption measurements using table-top LPP sources.

", "date": "2025-05-05", "date_type": "published", "publication": "ChemPhysChem", "volume": "26", "number": "9", "publisher": "Wiley", "pagerange": "e202400857", "issn": "1439-4235", "official_url": "https://authors.library.caltech.edu/records/16htd-dqr46", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, {}, {} ] }, "local_group": { "items": [ { "id": "Division-of-Chemistry-and-Chemical-Engineering" }, { "id": "Division-of-Engineering-and-Applied-Science" }, { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/cphc.202400857", "pub_year": "2025", "author_list": "Nimlos, Danika; Arellano, Alejandro; et al." }, { "id": "https://authors.library.caltech.edu/records/9sejj-ymy27", "eprint_status": "archive", "datestamp": "2025-04-16 17:57:33", "lastmod": "2025-07-03 19:11:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Korol-Roman", "name": { "family": "Korol", "given": "Roman" }, "orcid": "0000-0001-9307-6351" }, { "name": { "family": "Turner", "given": "Andrew C." }, "orcid": "0000-0003-1187-2560" }, { "name": { "family": "Nandi", "given": "Apurba" }, "orcid": "0000-0002-6191-5584" }, { "name": { "family": "Bowman", "given": "Joel M." }, "orcid": "0000-0001-9692-2672" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "name": { "family": "Stolper", "given": "Daniel A." }, "orcid": "0000-0003-3299-3177" } ] }, "title": "Stable isotope equilibria in the dihydrogen-water-methane-ethane-propane system. Part 1: Path-integral calculations with CCSD(T) quality potentials", "ispublished": "pub", "full_text_status": "public", "keywords": "Clumped isotope effects; Site-specific isotope effects; Alkanes; Stable isotope fractionations; Path integral calculations", "note": "

© 2025 Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

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DAS acknowledges support from the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division, under Award Numbers DE-AC02-05CH11231 and DE-SC0022949. WGIII acknowledges support from the National Science Foundation under award number CBET-2311117 The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. RK thanks Dr. Tomislav Beguši\u0107 for helpful discussions.

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Data are available through Mendeley Data at https://doi.org/10.17632/2kn87g7d46.1

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Supplementary Data 1 (PDF)

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Supplementary Data 2 (XLSX)

", "abstract": "
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Isotopic compositions of alkanes are typically assumed to be kinetically controlled, but recently it has been proposed that alkanes can isotopically equilibrate for both C and H isotopes during natural gas generation. Evaluation of this requires knowledge of the isotopic equilibrium between alkanes and other common hydrogen and carbon bearing species. Here we calculate isotopic equilibria within and between gaseous dihydrogen (H2), water (H2O), methane (CH4), ethane (C2H6) and propane (C3H8), including isotope fractionation among molecules, clumped isotope effects, as well as among sites of propane (i.e., the site-specific isotope effects) from 0°C to 500°C using a path-integral method paired with high-level descriptions of molecular potentials and the diagonal correction to the Born–Oppenheimer approximation. While path-integral calculations with high-level CCSD(T) potentials are available for the isotopic equilibria involving methane, the path-integral calculations for ethane and propane have only been performed based on lower-level descriptions of the molecular potentials. We analyze the relative importance of various approximations that are commonly employed when isotopic equilibria are evaluated. We find that clumped isotope effects can be calculated to the same accuracy using computationally inexpensive combination of the Bigeleisen-Mayer-Urey model with the molecular potential from density functional theory. In contrast, fractionation and site preferences of both deuterium and carbon-13 benefit from the use of the higher level CCSD(T) potentials and accounting for anharmonic effects. Additionally, for fractionation and site preference of deuterium, corrections to Born–Oppenheimer approximation can also be important.
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", "date": "2025-05-01", "date_type": "published", "publication": "Geochimica et Cosmochimica Acta", "volume": "396", "publisher": "Elsevier", "pagerange": "71-90", "issn": "0016-7037", "official_url": "https://authors.library.caltech.edu/records/9sejj-ymy27", "funders": { "items": [ { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "DE-SC0022949" }, { "grant_number": "CBET-2311117" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Chemistry-and-Chemical-Engineering" } ] }, "doi": "10.1016/j.gca.2025.02.028", "primary_object": { "basename": "1-s2.0-S0016703725001061-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/9sejj-ymy27/files/1-s2.0-S0016703725001061-mmc1.pdf" }, "related_objects": [ { "basename": "1-s2.0-S0016703725001061-mmc2.xlsx", "url": "https://authors.library.caltech.edu/records/9sejj-ymy27/files/1-s2.0-S0016703725001061-mmc2.xlsx" } ], "pub_year": "2025", "author_list": "Korol, Roman; Turner, Andrew C.; et al." }, { "id": "https://authors.library.caltech.edu/records/m4fsp-edw15", "eprint_status": "archive", "datestamp": "2026-01-08 16:06:45", "lastmod": "2026-01-08 16:06:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peng-Shirui", "name": { "family": "Peng", "given": "Shirui" }, "orcid": "0000-0002-4616-4604" }, { "id": "Callies-J", "name": { "family": "Callies", "given": "Joern" }, "orcid": "0000-0002-6815-1230" } ] }, "title": "Estimating temperature variability and trends from a combination of seismic and in situ data", "ispublished": "pub", "full_text_status": "public", "keywords": "ocean warming; physical oceanography; seismic ocean thermometry; Gaussian process modelling", "note": "

© 2025 The Author(s) Published by the Royal Society. All rights reserved.

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The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.

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This material is based upon work supported in part by the Resnick Sustainability Institute and in part by the National Science Foundation (grant no. OCE-2023161).

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S.P.: conceptualization, data curation, formal analysis, investigation, methodology, validation, visualization, writing—original draft, writing—review and editing; J.C.: conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, resources, software, supervision, visualization, writing—review and editing.

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Both authors gave final approval for publication and agreed to be held accountable for the work performed therein.

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The IMS hydrophone data are available directly from the CTBTO upon request and signing a confidentiality agreement to access the virtual Data Exploitation Centre (vDEC: www.ctbto.org/resources/for-researchers-experts/vdec). All seismic data were downloaded through IRIS Data Management Center https://ds.iris.edu/ds/nodes/dmc/, including the seismic networks II (GSN; [41]), IU, PS, G [42]. Global Seismographic Network (GSN) is a cooperative scientific facility operated jointly by the Incorporated Research Institutions for Seismology (IRIS), the United States Geological Survey (USGS) and the National Science Foundation (NSF), under Cooperative Agreement EAR-1261681. Bathymetry data were downloaded from and freely available at https://download.gebco.net/. The Argo data were downloaded from https://sio-argo.ucsd.edu/RG_Climatology.html. Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it (www.argo.ucsd.edu, http://argo.jcommops.org). The Argo Program is part of the Global Ocean Observing System. The ECCO data were available at https://podaac.jpl.nasa.gov/dataset/ECCO_L4_TEMP_SALINITY_05DEG_DAILY_V4R4. The processing code is available at [43,44].

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Yes, we have used AI-assisted technologies in creating this article. During the preparation of this manuscript, the authors utilized Artificial Intelligence (AI) language model assistance (e.g., Google's Gemini) for specific, limited tasks as permitted by the journal's policy. AI assistance was employed solely to revise the abstract for conciseness, ensuring adherence to the specified word count limit, and to improve its language and readability. AI assistance was also used in drafting this disclosure statement. This usage did not involve generating scientific insights, analysing or interpreting data, or drawing scientific conclusions. The authors carefully reviewed, edited, and approved all AI-generated suggestions and take full responsibility for the veracity, correctness, and originality of the entire manuscript content, ensuring it accurately represents their work and intellectual contributions.

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", "abstract": "

Estimating the large-scale variability and trends in subsurface ocean temperatures is limited by sparse in situ observations inadequate for resolving mesoscale eddies. Travel times of seismically generated sound waves, sensitive to path-integrated temperature, provide complementary integral constraints. We here use earthquakes along the Japan Trench and receivers at Wake Island to sample the Kuroshio Extension region in the Northwest Pacific. We develop a Gaussian process framework, optimized via maximum likelihood, to estimate temperature anomalies and uncertainties from this seismic data and to combine it with in situ data from Argo profiles and shipboard data. This framework shows seismic measurements are quantitatively consistent with in situ data and substantially reduce uncertainties in large-scale variability and trends. Relative to their prior, error variances of area-mean temperature fluctuations due to mesoscale eddies from 2008 to 2021 are reduced by 30% by the in situ data, 39% by the seismic data and 50% by the combination. For path-mean estimates, the combined reduction is 83% in error variances, compared to 45% from in situ data alone. The data show a steady subsurface warming of 11.8 ± 5.0 mK yr\u207b¹ (2σ uncertainty) from 2008 to 2021 and no substantial trend between 1997 and 2008.

", "date": "2025-05", "date_type": "published", "publication": "Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences", "volume": "481", "number": "2313", "publisher": "The Royal Society", "pagerange": "20240494", "issn": "1364-5021", "official_url": "https://authors.library.caltech.edu/records/m4fsp-edw15", "funders": { "items": [ { "grant_number": "-" }, { "agency": "National Science Foundation", "grant_number": "OCE-2023161" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1098/rspa.2024.0494", "pub_year": "2025", "author_list": "Peng, Shirui and Callies, Joern" }, { "id": "https://authors.library.caltech.edu/records/6084e-d6f47", "eprint_status": "archive", "datestamp": "2025-04-16 17:31:49", "lastmod": "2025-04-17 20:40:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Geyman-Emily-C", "name": { "family": "Geyman", "given": "Emily C." }, "orcid": "0000-0003-4349-9350" }, { "id": "Ke-Yutian", "name": { "family": "Ke", "given": "Yutian" }, "orcid": "0000-0002-9098-9419" }, { "id": "Magyar-John-S", "name": { "family": "Magyar", "given": "John S." }, "orcid": "0000-0002-3586-8286" }, { "name": { "family": "Reahl", "given": "Jocelyn N." }, "orcid": "0000-0001-5544-2138" }, { "name": { "family": "Soldano", "given": "Vincent" }, "orcid": "0009-0000-0326-0009" }, { "name": { "family": "Brown", "given": "Nathan D." }, "orcid": "0000-0002-7385-8679" }, { "name": { "family": "West", "given": "A. Joshua" }, "orcid": "0000-0001-6909-1471" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward" }, "orcid": "0000-0002-8836-3054" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Scaling laws for sediment storage and turnover in river floodplains", "ispublished": "pub", "full_text_status": "public", "note": "

© 2025 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).

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We thank the Huslia, Beaver, and Alakanuk tribal and village councils for river and land access and the Yukon River Inter-Tribal Watershed Council for logistical support. We thank A. Attla, D. Dayton, S. Huffman, K. Vanderpool, R. Williams, C. Wiehl, J. Isidore, P. Phillips Jr., R. Stanislaus, and J. Stronghearts for river navigation and expertise. We thank M. Douglas for creating the initial version of the floodplain relative age map at Huslia (30). We also thank J. Anadu, R. Blankenship, M. Douglas, K. Dunne, H. Dion-Kirschner, E. Mutter, J. Nghiem, E. Seelen, and I. Smith for help in the field.

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This work was supported by NSF award 2127442 and Caltech’s Resnick Sustainability Institute. E.C.G. thanks the NSF Graduate Research Fellowships Program and the Fannie and John Hertz Foundation.

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All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. The 14C data, OSL data, and relative age maps are archived at https://doi.org/10.18739/A2NC5SF1K. The satellite-derived migration rates, based on the algorithm of Geyman et al. (27), are archived at https://doi.org/10.18739/A2WW7719J.

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Supplementary Text; Figs. S1 to S22; Tables S1 to S14; References (PDF)

", "abstract": "

Nearly 10% of Earth's continents are covered by river floodplains. These landscapes serve as weathering reactors whereby particles eroded from mountains undergo chemical and physical alteration before being exported to oceans. The time a particle spends in floodplain reservoirs regulates the style and extent of continental chemical weathering and the fate of terrestrial organic carbon. Despite its importance for the global carbon cycle, we still lack a quantitative understanding of floodplain storage timescales. Using a combination of geomorphic mapping, radiocarbon and luminescence dating, and numerical simulations of meander dynamics, we identify well-conserved scaling laws that describe floodplain storage times. Our results reveal that, to first order, floodplain storage durations are set by the ratio of river width to migration rate. The fact that most rivers erode about 1% of their width per year leads to a typical floodplain storage duration of ~5 thousand years.

", "date": "2025-04-11", "date_type": "published", "publication": "Science Advances", "volume": "11", "number": "15", "publisher": "American Association for the Advancement of Science", "pagerange": "eadu8574", "issn": "2375-2548", "official_url": "https://authors.library.caltech.edu/records/6084e-d6f47", "funders": { "items": [ { "grant_number": "RISE-2127442" }, {}, { "grant_number": "-" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/sciadv.adu8574", "pmcid": "PMC11988448", "primary_object": { "basename": "sciadv.adu8574.pdf", "url": "https://authors.library.caltech.edu/records/6084e-d6f47/files/sciadv.adu8574.pdf" }, "related_objects": [ { "basename": "sciadv.adu8574_sm.pdf", "url": "https://authors.library.caltech.edu/records/6084e-d6f47/files/sciadv.adu8574_sm.pdf" } ], "pub_year": "2025", "author_list": "Geyman, Emily C.; Ke, Yutian; et al." }, { "id": "https://authors.library.caltech.edu/records/dtta6-0sp55", "eprint_status": "archive", "datestamp": "2025-11-18 02:34:36", "lastmod": "2025-11-18 02:34:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peng-Shirui", "name": { "family": "Peng", "given": "Shirui" }, "orcid": "0000-0002-4616-4604" }, { "id": "Callies-J", "name": { "family": "Callies", "given": "J\u00f6rn" }, "orcid": "0000-0002-6815-1230" }, { "name": { "family": "Nagura", "given": "Motoki" }, "orcid": "0000-0002-0594-4823" }, { "name": { "family": "McPhaden", "given": "Michael J." }, "orcid": "0000-0002-8423-5805" } ] }, "title": "Yanai Waves in the Deep East Indian Ocean Observed with Seismic Ocean Tomography", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Oceanic waves; Acoustic measurements/effects; Numerical analysis/modeling; Tropical variability", "note": "

© 2025 American Meteorological Society.

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S. P. and J. C. gratefully acknowledge support from the National Science Foundation under Grant OCE-2023161. The computations presented here were conducted on the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. We sincerely thank Pattabhi Rama Rao and Uday Bhaskar of INCOIS, who kindly provided us with current-meter observations. This is PMEL Contribution 5644.

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The IMS hydrophone data are available directly from the CTBTO on request and signing a confidentiality agreement to access the virtual Data Exploitation Centre (vDEC: https://www.ctbto.org/resources/for-researchers-experts/vdec). All seismic data were downloaded through the IRIS Data Management Center (https://ds.iris.edu/ds/nodes/dmc/), including the seismic networks II (GSN; https://doi.org/10.7914/SN/II) and MY, PS, GE (https://doi.org/10.14470/TR560404). Global Seismographic Network (GSN) is a cooperative scientific facility operated jointly by the Incorporated Research Institutions for Seismology (IRIS), the U.S. Geological Survey (USGS), and the National Science Foundation (NSF), under Cooperative Agreement EAR-1261681. Bathymetry data were downloaded from and freely available at https://download.gebco.net/. Argo data were downloaded from https://sio-argo.ucsd.edu/RG_Climatology.html. Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it (https://www.argo.ucsd.edu and https://www.ocean-ops.org). The Argo program is part of the Global Ocean Observing System. ECCO data were available at https://podaac.jpl.nasa.gov/dataset/ECCO_L4_TEMP_SALINITY_05DEG_DAILY_V4R4. The processing code is available at https://github.com/joernc/sot and https://github.com/Shirui-peng/SOTgpm. The sediment thickness data were downloaded from https://ngdc.noaa.gov/mgg/sedthick/. JRA-55-do dataset is provided online (https://esgf-node.llnl.gov/search/input4mips/ search with the keyword “OMIP”). The mooring velocity data are available from INCOIS (https://incois.gov.in/portal/datainfo/cm.jsp).

", "abstract": "

Near-surface measurements of meridional velocity suggest that wind forcing excites equatorial waves in the biweekly band in the Indian Ocean. The characteristics of these waves in the deep ocean are poorly constrained, and it is unclear how well models capture the deep variability. In this work, biweekly temperature variations in a few low vertical modes in the deep east Indian Ocean are observed using seismically generated sound waves. These so-called T waves are generated by earthquakes off Sumatra and received by a hydrophone station off Diego Garcia. Changes in their travel times reflect temperature-induced sound speed variations in the intervening ocean. Regression analysis indicates that these variations are caused by westward-propagating Yanai waves. A comparison between T-wave data and model output shows generally good consistency in biweekly variations dominated by the first three vertical modes, although the biweekly variance differs by up to a factor of 2 between the data and the models. A similar degree of discrepancy appears in the comparison between the models and deep mooring measurements. These results highlight the potential of using T-wave data to study biweekly Yanai waves in the deep equatorial ocean and to calibrate numerical simulations of the variability they cause. Significance Statement Biweekly Yanai waves are an important mode of variability in the tropical Indian Ocean, affecting the Indian and Australian–Indonesian monsoons. This study examines biweekly Yanai waves in the east Indian Ocean using sound waves generated by natural repeating earthquakes. The sound waves sample the deep structure of Yanai waves, which has been poorly constrained by previous observations. The seismic data generally show good consistency with output from two ocean general circulation models, although quantitative differences are manifested and can help improve the representation of Yanai waves in numerical models.

", "date": "2025-04-01", "date_type": "published", "publication": "Journal of Physical Oceanography", "volume": "55", "number": "4", "publisher": "American Meteorological Society", "pagerange": "471-488", "issn": "0022-3670", "official_url": "https://authors.library.caltech.edu/records/dtta6-0sp55", "funders": { "items": [ { "agency": "National Science Foundation", "grant_number": "OCE-2023161" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1175/jpo-d-24-0107.1", "primary_object": { "basename": "phoc-JPO-D-24-0107.1.pdf", "url": "https://authors.library.caltech.edu/records/dtta6-0sp55/files/phoc-JPO-D-24-0107.1.pdf" }, "pub_year": "2025", "author_list": "Peng, Shirui; Callies, J\u00f6rn; et al." }, { "id": "https://authors.library.caltech.edu/records/0e1mx-kkj12", "eprint_status": "archive", "datestamp": "2025-03-27 21:19:59", "lastmod": "2025-03-27 21:20:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Magistro-Beatrice", "name": { "family": "Magistro", "given": "Beatrice" }, "orcid": "0000-0001-7423-3577" }, { "id": "Debnath-Ramit", "name": { "family": "Debnath", "given": "Ramit" }, "orcid": "0000-0003-0727-5683" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. Michael" }, "orcid": "0000-0002-8113-4451" } ] }, "title": "Partisanship overcomes framing in shaping solar geoengineering perceptions: Evidence from a conjoint experiment", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate-change mitigation; Environmental social sciences; Psychology and behaviour; Social sciences", "note": "

© The Author(s) 2025.

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This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

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R.M.A. and B.M.'s work is supported by Caltech's Resnick Sustainability Institute. RD's work is supported by the Cambridge Arts, Humanities and Social Science (AHSS) Grants, Keynes Fund [JHVH] and the Bill & Melinda French Gates Foundation (OPP1144).

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Upon publication, the code and data necessary to reproduce the results reported in this paper will be made available in a permanent and public data repository, subject to any limitations imposed by human subjects considerations.

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The data collection and analysis procedures were reviewed by Caltech’s Institutional Research Board and were ruled exempt (IRB 22-1220). Informed consent was obtained from all participants.

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Appendix

", "abstract": "

The discourse on solar geoengineering (SG) is evolving, yet public perceptions of SG as a climate change solution remain underexplored, especially in the polarized US political landscape. We examine the relative importance of different SG narratives—framed as complementary, substitutive, or posing a moral hazard—and partisan information sources in shaping public attitudes. Using a conjoint experiment with 2123 American voters, we find that partisan alignment with the information source plays a decisive role in shaping trust in the messenger and support for SG, overshadowing any impact of message framing. Both Democrats and Republicans are more likely to trust the messenger and support SG when the information comes from a copartisan source. However, despite these strong partisan influences, policy preferences remain consistent with ideological baselines. These findings highlight the importance of partisanship in shaping perceptions of emerging climate technologies such as SG, even in contexts of low public awareness, and underscore the challenges of depolarizing public discourse on climate change solutions.

", "date": "2025-03-24", "date_type": "published", "publication": "npj Climate Action", "volume": "4", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "29", "issn": "2731-9814", "official_url": "https://authors.library.caltech.edu/records/0e1mx-kkj12", "funders": { "items": [ {}, {}, { "agency": "Keynes Fund", "grant_number": "JHVH" }, { "grant_number": "OPP1144" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-the-Humanities-and-Social-Sciences" } ] }, "doi": "10.1038/s44168-025-00236-3", "primary_object": { "basename": "s44168-025-00236-3.pdf", "url": "https://authors.library.caltech.edu/records/0e1mx-kkj12/files/s44168-025-00236-3.pdf" }, "related_objects": [ { "basename": "44168_2025_236_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/0e1mx-kkj12/files/44168_2025_236_MOESM1_ESM.pdf" } ], "pub_year": "2025", "author_list": "Magistro, Beatrice; Debnath, Ramit; et al." }, { "id": "https://authors.library.caltech.edu/records/8ac4g-wjt05", "eprint_status": "archive", "datestamp": "2025-03-28 20:38:34", "lastmod": "2025-03-28 20:38:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chadwick-K-Dana", "name": { "family": "Chadwick", "given": "K. Dana" }, "orcid": "0000-0002-5633-4865" }, { "name": { "family": "Davis", "given": "Frank" }, "orcid": "0000-0002-4643-5718" }, { "id": "Miner-Kimberley-R", "name": { "family": "Miner", "given": "Kimberley R." }, "orcid": "0000-0002-1006-1283" }, { "id": "Pavlick-Ryan", "name": { "family": "Pavlick", "given": "Ryan" }, "orcid": "0000-0001-8772-3508" }, { "name": { "family": "Reynolds", "given": "Mark" } }, { "name": { "family": "Townsend", "given": "Philip A." }, "orcid": "0000-0001-7003-8774" }, { "id": "Brodrick-Philip-G", "name": { "family": "Brodrick", "given": "Philip G." }, "orcid": "0000-0001-9497-7661" }, { "id": "Ade-Christiana", "name": { "family": "Ade", "given": "Christiana" }, "orcid": "0000-0001-6415-6774" }, { "name": { "family": "Allen", "given": "Jean" }, "orcid": "0000-0001-9299-9912" }, { "name": { "family": "Anderegg", "given": "Leander" } }, { "name": { "family": "Angel", "given": "Yoseline" }, "orcid": "0000-0002-8377-8736" }, { "name": { "family": "Boving", "given": "Indra" } }, { "name": { "family": "Byrd", "given": "Kristin B." }, "orcid": "0000-0002-5725-7486" }, { "name": { "family": "Campbell", "given": "Petya" }, "orcid": "0000-0002-0505-4951" }, { "name": { "family": "Carberry", "given": "Luke" } }, { "name": { "family": "Cavanaugh", "given": "Katherine C." } }, { "name": { "family": "Cavanaugh", "given": "Kyle C." } }, { "name": { "family": "Easterday", "given": "Kelly" } }, { "id": "Eckert-Regina", "name": { "family": "Eckert", "given": "Regina" } }, { "id": "Gierach-Michelle", "name": { "family": "Gierach", "given": "Michelle" }, "orcid": "0000-0002-8161-4121" }, { "id": "Gold-Kaitlin", "name": { "family": "Gold", "given": "Kaitlin" }, "orcid": "0000-0002-0306-9244" }, { "name": { "family": "Hestir", "given": "Erin" } }, { "name": { "family": "Huemmrich", "given": "Fred" } }, { "name": { "family": "Klope", "given": "Maggie" } }, { "name": { "family": "Kokaly", "given": "Raymond F" }, "orcid": "0000-0003-0276-7101" }, { "name": { "family": "Lovegreen", "given": "Piper" } }, { "id": "Luis-Kelly", "name": { "family": "Luis", "given": "Kelly" }, "orcid": "0000-0001-9975-3480" }, { "name": { "family": "McMahon", "given": "Conor" }, "orcid": "0000-0003-4162-6168" }, { "name": { "family": "Nidzieko", "given": "Nicholas" } }, { "name": { "family": "Ochoa", "given": "Francisco" } }, { "name": { "family": "Ongjoco", "given": "Anna Jiselle" } }, { "name": { "family": "Ordway", "given": "Elsa" }, "orcid": "0000-0002-7720-1754" }, { "id": "Pascolini-Campbell-Madeleine", "name": { "family": "Pascolini-Campbell", "given": "Madeleine" }, "orcid": "0000-0002-6449-0841" }, { "name": { "family": "Queally", "given": "Natalie" } }, { "name": { "family": "Roberts", "given": "Dar A." }, "orcid": "0000-0002-3555-4842" }, { "name": { "family": "Saiki", "given": "Clare M." } }, { "id": "Schneider-Fabian-D", "name": { "family": "Schneider", "given": "Fabian D." } }, { "name": { "family": "Shiklomanov", "given": "Alexey N." }, "orcid": "0000-0003-4022-5979" }, { "name": { "family": "Silva", "given": "Germ\u00e1n D." }, "orcid": "0000-0002-7931-1957" }, { "name": { "family": "Snyder", "given": "Jordan" } }, { "name": { "family": "Thornton", "given": "Michele" } }, { "name": { "family": "Trugman", "given": "Anna T." } }, { "name": { "family": "Vinod", "given": "Nidhi" } }, { "name": { "family": "Zheng", "given": "Ting" } }, { "name": { "family": "Avouris", "given": "Dulcinea M." } }, { "name": { "family": "Baker", "given": "Brianna" } }, { "id": "Baskaran-Latha", "name": { "family": "Baskaran", "given": "Latha" } }, { "name": { "family": "Bell", "given": "Tom" }, "orcid": "0000-0002-0173-2866" }, { "name": { "family": "Berg", "given": "Megan" } }, { "name": { "family": "Bernas", "given": "Michael" } }, { "id": "Bohn-Niklas", "name": { "family": "Bohn", "given": "Niklas" } }, { "id": "Braghiere-Renato-K", "name": { "family": "Braghiere", "given": "Renato K." }, "orcid": "0000-0002-7722-717X" }, { "name": { "family": "Breuer", "given": "Zach" } }, { "name": { "family": "Brooks", "given": "Andrew J." }, "orcid": "0000-0002-6651-1204" }, { "name": { "family": "Burkard", "given": "Nolan" } }, { "name": { "family": "Burmistrova", "given": "Julia" } }, { "id": "Cawse-Nicholson-Kerry", "name": { "family": "Cawse-Nicholson", "given": "Kerry" }, "orcid": "0000-0002-0510-4066" }, { "id": "Chapman-John", "name": { "family": "Chapman", "given": "John" }, "orcid": "0009-0005-3602-4199" }, { "name": { "family": "Chazaro\u2010Haraksin", "given": "Johana" } }, { "name": { "family": "Cryer", "given": "Joel" } }, { "id": "Cushman-K-C", "name": { "family": "Cushman", "given": "K. C." } }, { "name": { "family": "Dahlin", "given": "Kyla" }, "orcid": "0000-0002-6016-2605" }, { "name": { "family": "Dao", "given": "Phuong D." }, "orcid": "0000-0002-3712-9022" }, { "name": { "family": "DiBartolo", "given": "Athena" } }, { "id": "Eastwood-Michael", "name": { "family": "Eastwood", "given": "Michael" }, "orcid": "0000-0002-4731-6083" }, { "id": "Elder-Clayton-D", "name": { "family": "Elder", "given": "Clayton D." }, "orcid": "0000-0001-9831-2106" }, { "name": { "family": "Giordani", "given": "Angela" } }, { "name": { "family": "Grant", "given": "Kathleen" } }, { "id": "Green-Robert-O", "name": { "family": "Green", "given": "Robert O." }, "orcid": "0000-0001-9447-3076" }, { "name": { "family": "Hanson", "given": "Alexa" } }, { "name": { "family": "Heberlein", "given": "Brendan" } }, { "id": "Helmlinger-Mark", "name": { "family": "Helmlinger", "given": "Mark" } }, { "id": "Hook-Simon", "name": { "family": "Hook", "given": "Simon" }, "orcid": "0000-0002-0953-6165" }, { "id": "Jensen-Daniel", "name": { "family": "Jensen", "given": "Daniel" }, "orcid": "0000-0003-3331-2847" }, { "name": { "family": "Johnson", "given": "Emma" }, "orcid": "0009-0007-9640-8893" }, { "name": { "family": "Johnson", "given": "Marie" }, "orcid": "0000-0002-7705-5670" }, { "id": "Kiper-Michael", "name": { "family": "Kiper", "given": "Michael" }, "orcid": "0009-0003-7282-0745" }, { "name": { "family": "Kibler", "given": "Christopher" } }, { "name": { "family": "King", "given": "Jennifer Y." }, "orcid": "0000-0003-3433-5952" }, { "name": { "family": "Kovach", "given": "Kyle R." }, "orcid": "0000-0002-1498-6363" }, { "name": { "family": "Kreisberg", "given": "Aaron" } }, { "name": { "family": "Lacey", "given": "Daniel" } }, { "name": { "family": "Lang", "given": "Evan" } }, { "id": "Lee-Christine", "name": { "family": "Lee", "given": "Christine" } }, { "id": "Lopez-Amanda-M", "name": { "family": "Lopez", "given": "Amanda M." } }, { "name": { "family": "Lopez Barreto", "given": "Brittany" } }, { "id": "Maguire-Andrew", "name": { "family": "Maguire", "given": "Andrew" }, "orcid": "0000-0002-6334-0497" }, { "name": { "family": "Marsh", "given": "Elliott" } }, { "id": "Miller-Charles", "name": { "family": "Miller", "given": "Charles" }, "orcid": "0000-0002-9380-4838" }, { "name": { "family": "Nguyen", "given": "Dieu My T." } }, { "id": "Nickles-Cassandra", "name": { "family": "Nickles", "given": "Cassandra" } }, { "name": { "family": "Oc\u00f3n", "given": "Jonathan P." }, "orcid": "0000-0002-3899-9062" }, { "name": { "family": "Papen", "given": "Elijah P." } }, { "name": { "family": "Park", "given": "Maria" } }, { "name": { "family": "Poulter", "given": "Benjamin" } }, { "name": { "family": "Raiho", "given": "Ann" }, "orcid": "0000-0002-2552-3399" }, { "name": { "family": "Reim", "given": "Porter" } }, { "name": { "family": "Robinson", "given": "Timothy H." } }, { "name": { "family": "Romero Galvan", "given": "Fernando E." } }, { "id": "Shafron-Ethan", "name": { "family": "Shafron", "given": "Ethan" } }, { "name": { "family": "Skalitzky", "given": "Brenen R." } }, { "name": { "family": "Stroschein", "given": "Sydney" } }, { "name": { "family": "Taylor", "given": "Niky C." } }, { "id": "Thompson-David-R", "name": { "family": "Thompson", "given": "David R." }, "orcid": "0000-0003-1100-7550" }, { "name": { "family": "Thompson", "given": "Kate" } }, { "name": { "family": "Tye", "given": "Cecily" } }, { "name": { "family": "Van Beek", "given": "Joelie" } }, { "name": { "family": "Vanden Heuvel", "given": "Cecilia" } }, { "name": { "family": "Vellanoweth", "given": "Jonathan" } }, { "name": { "family": "Vermeer", "given": "Evert" } }, { "id": "Villanueva-Weeks-Claire", "name": { "family": "Villanueva-Weeks", "given": "Claire" } }, { "name": { "family": "Zumdahl", "given": "Kristen" } }, { "id": "Schimel-David", "name": { "family": "Schimel", "given": "David" }, "orcid": "0000-0003-3473-8065" } ] }, "title": "Unlocking ecological insights from sub-seasonal visible-to-shortwave infrared imaging spectroscopy: The SHIFT campaign", "ispublished": "pub", "full_text_status": "public", "keywords": "Airborne Visible InfraRed Imaging Spectrometer (AVIRIS); phenology; SHIFT campaign; Special Feature: Insights from Sub-Seasonal Imaging Spectroscopy; surface biology geology mission; visible-to-shortwave infrared (VSWIR) imaging spectroscopy", "note": "

© 2025 The Author(s). Ecosphere published by Wiley Periodicals LLC on behalf of The Ecological Society of America.

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This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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Sedgwick staff: Lyza Johnsen, Angela Giordani, Brenda Juarez, and Nicole Evans for logistical and administrative support. Frank Davis acknowledges the La Kretz Center for Research at Sedgwick. Some of the research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. Government sponsorship is acknowledged. This study was also supported by the Surface Biology and Geology (SBG) mission's pre-Phase A activites, a NASA Earth Science Designated Observable. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Renato K. Braghiere acknowledges support by Resnick Sustainability Institute. Kyla Dahlin acknowledges support from National Science Foundation award #2044818. We acknowledge the support from Richard Smalldon from the Santa Barbara Museum of Natural History Sea Center. On behalf of all participants from the University of Wisconsin, Philip A. Townsend acknowledges support from the NASA SBG project through JPL award 1673139 and the NSF ASCEND Biology Integration Institute (BII) award DBI 2021898. Natalie Queally was additionally supported by NASA FINESST fellowship 80NSSC22K1532. Katie Gold acknowledges support from JPL Strategic University Research Partnership awarded to Cornell Univeristy and NASA Acres.

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All in situ datasets and remote SHIFT observations funded through the SBG mission are archived through the Oak Ridge National Laboratory Distributed Active Archive Center (ORNL DAAC, https://daac.ornl.gov/shift) and made available to NASA Earthdata including NASA Earthdata cloud-based access (https://doi.org/10.3334/ORNLDAAC/2334; https://doi.org/10.3334/ORNLDAAC/2184; https://doi.org/10.3334/ORNLDAAC/2337; https://doi.org/10.3334/ORNLDAAC/2295; https://doi.org/10.3334/ORNLDAAC/2233; https://doi.org/10.3334/ORNLDAAC/2244; https://doi.org/10.3334/ORNLDAAC/2189; https://doi.org/10.3334/ORNLDAAC/2245; https://doi.org/10.3334/ORNLDAAC/2246; https://doi.org/10.3334/ORNLDAAC/2234; https://doi.org/10.3334/ORNLDAAC/2242; https://doi.org/10.3334/ORNLDAAC/2376). All data are openly shared without restriction in accordance with NASA's Earth Science program Data and Information Policy.

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Appendix S1

", "abstract": "
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We stand at the threshold of a transformative era in Earth observation, marked by space-borne visible-to-shortwave infrared (VSWIR) imaging spectrometers that promise consistent global observations of ecosystem function, phenology, and inter- and intra-annual change. However, the full value of repeat spectroscopy, the information embedded within different temporal scales, and the reliability of existing algorithms across diverse ecosystem types and vegetation phenophases have remained elusive due to the absence of suitable sub-seasonal spectroscopy data. In response, the Surface Biology and Geology (SBG) High-Frequency Time Series (SHIFT) campaign was initiated during late February 2022 in Santa Barbara County, California. SHIFT, designed to support NASA's SBG mission, addressed mission scoping, scientific advancement, applications development, and community building. This ambitious endeavor included weekly Airborne Visible InfraRed Imaging Spectrometer-Next Generation (AVIRIS-NG) imagery acquisitions for 13 weeks (spanning February 24 to May 29, 2022), accompanied by coordinated terrestrial vegetation and coastal aquatic data collection. We describe the rich datasets collected and illustrate how the complex sub-seasonal patterns of change can be linked to biological science and applications, surpassing insights from multispectral observations. Leveraging open-source processing methods and cloud-based analysis tools, the SHIFT campaign showcases the readiness of the scientific community to harness ecological insights from remotely sensed hyperspectral time series. We provide an overview of SHIFT's goals, data collections, preliminary results, and the collaborative efforts of early career scientists committed to unlocking the transformative potential of high-frequency time series data from space-borne VSWIR imaging spectrometers.

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", "date": "2025-03", "date_type": "published", "publication": "Ecosphere", "volume": "16", "number": "3", "publisher": "Wiley", "pagerange": "e70194", "issn": "2150-8925", "official_url": "https://authors.library.caltech.edu/records/8ac4g-wjt05", "funders": { "items": [ { "grant_number": "1673139" }, { "grant_number": "80NSSC22K1532" }, {}, { "grant_number": "2044818" }, { "grant_number": "DBI-2021898" }, { "grant_number": "-" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/ecs2.70194", "primary_object": { "basename": "Ecosphere - 2025 - Chadwick - Unlocking ecological insights from sub\u2010seasonal visible\u2010to\u2010shortwave infrared imaging.pdf", "url": "https://authors.library.caltech.edu/records/8ac4g-wjt05/files/Ecosphere - 2025 - Chadwick - Unlocking ecological insights from sub\u2010seasonal visible\u2010to\u2010shortwave infrared imaging.pdf" }, "related_objects": [ { "basename": "ecs270194-sup-0001-appendix_s1.pdf", "url": "https://authors.library.caltech.edu/records/8ac4g-wjt05/files/ecs270194-sup-0001-appendix_s1.pdf" } ], "pub_year": "2025", "author_list": "Chadwick, K. Dana; Davis, Frank; et al." }, { "id": "https://authors.library.caltech.edu/records/vbhry-09e90", "eprint_status": "archive", "datestamp": "2025-09-20 13:28:17", "lastmod": "2025-09-20 22:31:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Yuexin", "name": { "family": "Li", "given": "Yuexin" }, "orcid": "0000-0002-0160-7504" }, { "id": "Acosta-Mateo", "name": { "family": "Acosta", "given": "Mateo" }, "orcid": "0000-0002-0098-7912" }, { "id": "Sirorattanakul-Krittanon", "name": { "family": "Sirorattanakul", "given": "Krittanon" }, "orcid": "0000-0003-2310-8447" }, { "name": { "family": "Bourne", "given": "Stephen" }, "orcid": "0000-0003-2925-8411" }, { "id": "Avouac-J-P", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" } ] }, "title": "Geodetic Monitoring of Elastic and Inelastic Deformation in Compacting Reservoirs Due To Subsurface Operations", "ispublished": "pub", "full_text_status": "public", "keywords": "InSAR; independent component analysis; land subsidence; reservoir compaction; seasonal deformation; Groningen gas field", "note": "

© 2025. American Geophysical Union.

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We would like to thank Manoochehr Shirzaei and an anonymous reviewer for their suggestions, which helped improve the manuscript. This study was supported by the NSF/Industry-University Collaborative Research Center ‘Geomechanics and Mitigation of Geohazards' (National Science Foundation award 1822214), and the Enhancement Project GMG-3 funded by Nederlandse Aardolie Maatschappij (NAM). M.A acknowledges funding from the Swiss National Science Foundation through Grant P2ELP2195127 and from Caltech's Resnick sustainability institute. We would like to acknowledge for granting the access and permitting to publish the InSAR and GNSS data.

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All InSAR, GNSS, and optical data were provided by Nederlandse Aardolie Maatschappij (NAM). The InSAR data were processed by SkyGeo (https://skygeo.com). Surface temperature data were retrieved from KNMI (https://dataplatform.knmi.nl/dataset/). The relevant InSAR, GNSS, and optical data necessary for the analysis in this article are available through Li et al. (2024) (https://doi.org/10.5281/zenodo.14184369). The vbICA software for ICA decomposition is available from Gualandi and Liu (2020) (https://doi.org/10.5281/zenodo.4322548). The reservoir modeling code is from Acosta et al. (2023a) (https://doi.org/10.5281/zenodo.8329298).

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Supporting Information S1 (DOCX)

", "abstract": "
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A variety of geo-energy operations involve extraction or injections of fluids, including hydrocarbon production or storage, hydrogen storage, CO2 sequestration, and geothermal energy production. The surface deformation resulting from such operations can be a source of information on reservoir geomechanical properties as we show in this study. We analyze the time-dependent surface deformation in the Groningen region in northeastern Netherlands using a comprehensive geodetic data set, which includes InSAR (Radarsat2, TerraSAR-X, Sentinel-1), GNSS, and optical leveling spanning several decades. We resort to an Independent Component Analysis (ICA) to isolate deformation signals of various origins. The signals related to gas production from the Groningen gas field and from seasonal storage at Norg Underground Gas Storage are clearly revealed. Surface deformation associated to the Groningen reservoir show decadal subsidence, with spatially variable subsidence rates dictated by local compressibility. The ICA reveals distinct seasonal fluctuations at Norg, closely mirroring the variations of gas storage. By comparing the observed long-term subsidence within the Groningen reservoir and seasonal oscillations at Norg from a linear poroelastic compaction model, we quantify the fraction of inelastic deformation of the reservoir in space and time and constrain the reservoir compressibility. In Groningen, increased compressibility indicates inelastic compaction that has built over time and might account for as much as 20% of the total compaction cumulated until 2021, while Norg shows no signs of inelastic deformation and a constant compressibility. This study provides a methodology to monitor and calibrate models of the subsurface deformation induced by geo-energy operations or aquifer management.

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", "date": "2025-03", "date_type": "published", "publication": "Journal of Geophysical Research: Solid Earth", "volume": "130", "number": "3", "publisher": "American Geophysical Union", "pagerange": "e2024JB030794", "issn": "2169-9313", "official_url": "https://authors.library.caltech.edu/records/vbhry-09e90", "funders": { "items": [ { "grant_number": "1822214" }, { "grant_number": "P2ELP2195127" } ] }, "local_group": { "items": [ { "id": "Center-for-Geomechanics-and-Mitigation-of-Geohazards-(GMG)" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2024jb030794", "primary_object": { "basename": "JGR Solid Earth - 2025 - Li - Geodetic Monitoring of Elastic and Inelastic Deformation in Compacting Reservoirs Due To.pdf", "url": "https://authors.library.caltech.edu/records/vbhry-09e90/files/JGR Solid Earth - 2025 - Li - Geodetic Monitoring of Elastic and Inelastic Deformation in Compacting Reservoirs Due To.pdf" }, "related_objects": [ { "basename": "2024jb030794-sup-0001-supporting information si-s01.docx", "url": "https://authors.library.caltech.edu/records/vbhry-09e90/files/2024jb030794-sup-0001-supporting information si-s01.docx" } ], "pub_year": "2025", "author_list": "Li, Yuexin; Acosta, Mateo; et al." }, { "id": "https://authors.library.caltech.edu/records/2cvsq-0a522", "eprint_status": "archive", "datestamp": "2024-12-17 18:28:02", "lastmod": "2024-12-17 18:28:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Huang", "given": "Daniel Zhengyu" } }, { "id": "Nelsen-Nicholas-H", "name": { "family": "Nelsen", "given": "Nicholas H." }, "orcid": "0000-0002-8328-1199" }, { "id": "Trautner-Margaret", "name": { "family": "Trautner", "given": "Margaret" }, "orcid": "0000-0001-9937-8393" } ] }, "title": "An operator learning perspective on parameter-to-observable maps", "ispublished": "pub", "full_text_status": "public", "keywords": "Operator learning; neural operator; quantity of interest; universal approximation; functional linear regression; sample complexity; Bayesian nonparametrics", "note": "

© 2024 American Institute of Mathematical Sciences.

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The first author is supported by the high-performance computing platform of Peking University. The second author acknowledges support from the National Science Foundation Graduate Research Fellowship Program under award number DGE-1745301 and from the Amazon/Caltech AI4Science Fellowship, and partial support from the Air Force Office of Scientific Research under MURI award number FA9550-20-1-0358 (Machine Learning and Physics-Based Modeling and Simulation). The third author is supported by the Department of Energy Computational Science Graduate Fellowship under award number DE-SC00211. The second and third authors are also grateful for partial support from the Department of Defense Vannevar Bush Faculty Fellowship held by Andrew M. Stuart under Office of Naval Research award number N00014-22-1-2790.

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The computations presented in this paper were partially conducted on the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. The authors thank Kaushik Bhattacharya for useful discussions about learning functionals, Andrew Stuart for helpful remarks about the universal approximation theory, and Zachary Morrow for providing the code for the advection–diffusion equation solver. The authors are also grateful for the helpful feedback from two anonymous referees.

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Links to datasets and all code used to produce the numerical results and figures in this paper are available at

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https://github.com/nickhnelsen/fourier-neural-mappings.

", "abstract": "

Computationally efficient surrogates for parametrized physical models play a crucial role in science and engineering. Operator learning provides data-driven surrogates that map between function spaces. However, instead of full-field measurements, often the available data are only finite-dimensional parametrizations of model inputs or finite observables of model outputs. Building on Fourier Neural Operators, this paper introduces the Fourier Neural Mappings (FNMs) framework that is able to accommodate such finite-dimensional vector inputs or outputs. The paper develops universal approximation theorems for the method. Moreover, in many applications the underlying parameter-to-observable (PtO) map is defined implicitly through an infinite-dimensional operator, such as the solution operator of a partial differential equation. A natural question is whether it is more data-efficient to learn the PtO map end-to-end or first learn the solution operator and subsequently compute the observable from the full-field solution. A theoretical analysis of Bayesian nonparametric regression of linear functionals, which is of independent interest, suggests that the end-to-end approach can actually have worse sample complexity. Extending beyond the theory, numerical results for the FNM approximation of three nonlinear PtO maps demonstrate the benefits of the operator learning perspective that this paper adopts.

", "date": "2025-03", "date_type": "published", "publication": "Foundations of Data Science", "volume": "7", "number": "1", "publisher": "American Institute of Mathematical Sciences (AIMS)", "pagerange": "163-225", "issn": "2639-8001", "official_url": "https://authors.library.caltech.edu/records/2cvsq-0a522", "funders": { "items": [ {}, { "grant_number": "DGE-1745301" }, { "grant_number": "Amazon/Caltech AI4Science Fellowship" }, { "grant_number": "FA9550-20-1-0358" }, { "grant_number": "DE-SC00211" }, { "grant_number": "Vannevar Bush Faculty Fellowship" }, { "grant_number": "N00014-22-1-2790" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3934/fods.2024037", "pub_year": "2025", "author_list": "Huang, Daniel Zhengyu; Nelsen, Nicholas H.; et al." }, { "id": "https://authors.library.caltech.edu/records/0d78c-tpe72", "eprint_status": "archive", "datestamp": "2025-02-12 00:11:52", "lastmod": "2025-02-12 00:11:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Tianyi", "name": { "family": "He", "given": "Tianyi" }, "orcid": "0000-0002-8191-188X" }, { "id": "Bruening-Meaghan-Ann", "name": { "family": "Bruening", "given": "Meaghan A." }, "orcid": "0000-0001-8132-9497" }, { "id": "Espinosa-Matthew-R", "name": { "family": "Espinosa", "given": "Matthew" }, "orcid": "0009-0007-3440-212X" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Novel Silicate Platform as Weakly\u2010Coordinating Anions for Diverse Organometallic and Electrochemical Applications", "ispublished": "pub", "full_text_status": "public", "keywords": "Weakly-coordinating anions; coordination chemistry; electrochemistry; magnesium batteries", "note": "

© 2024 Wiley-VCH GmbH

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This study was funded by the Resnick Sustainability Institute. We thank the Beckman Institute at Caltech and the Dow Next Generation Educator Fund for instrumentation support. We are grateful to Michael Takase for assistance with X-ray crystallography. We thank Kimberly See, Steven Stradley, and Christopher Povinelli for insightful discussions.

\n\n

The data that support the findings of this study are available in the supplementary material of this article.

\n\n

Supporting information: anie202417136-sup-0001-misc_information.pdf

", "abstract": "

Weakly-coordinating anions (WCAs) are employed in a wide range of applications, but limitations remain, including high reactivity, limited redox window, complicated synthesis, high cost, low solublity, and low structural tunabililty. Herein, we report a new class of WCA based on alkyl or aryl (R) substituted silicates bearing fluorinated pinacolate ligands, “[RSiF24]−”. Anions bearing a variety of R groups were prepared, enabling facile tuning of sterics and solubility. A range of cations employed in chemical reactivity has been supported by these anions, including ether-free alkali cations, Ag+, Ph3C+, Fc+, [NiI(COD)2]+. [Pd(dppe)(NCMe)Me]+ has been generated by salt metathesis or protonation of a metal-alkyl bond, showcasing the ability of the [RSiF24]− anions to support applications in coordination chemistry and catalysis. Electrochemical studies on the [Bu4N]+ variant show an exceptionally wide stability window for the [MeSiF24]− anion of 7.5\u2005V in MeCN. CV experiments demonstrate reversible Mg deposition and stripping.

", "date": "2025-01-21", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "64", "number": "4", "publisher": "Wiley", "pagerange": "e202417136", "issn": "1433-7851", "official_url": "https://authors.library.caltech.edu/records/0d78c-tpe72", "funders": { "items": [ {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.202417136", "primary_object": { "basename": "anie202417136-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/0d78c-tpe72/files/anie202417136-sup-0001-misc_information.pdf" }, "pub_year": "2025", "author_list": "He, Tianyi; Bruening, Meaghan A.; et al." }, { "id": "https://authors.library.caltech.edu/records/zabhn-2mt61", "eprint_status": "archive", "datestamp": "2025-01-10 21:36:12", "lastmod": "2025-02-12 00:14:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lotem-Noam", "name": { "family": "Lotem", "given": "Noam" }, "orcid": "0000-0001-5079-7482" }, { "name": { "family": "Rasmussen", "given": "Birger" }, "orcid": "0000-0002-2745-0904" }, { "name": { "family": "Zi", "given": "Jian-Wei" }, "orcid": "0000-0001-8094-7568" }, { "id": "Zeichner-Sarah-S", "name": { "family": "Zeichner", "given": "Sarah S." }, "orcid": "0000-0001-8897-7657" }, { "id": "Present-Theodore-M", "name": { "family": "Present", "given": "Theodore M." }, "orcid": "0000-0002-4747-2174" }, { "id": "Bar-On-Yinon-M", "name": { "family": "Bar-On", "given": "Yinon M." }, "orcid": "0000-0001-8477-609X" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward F." }, "orcid": "0000-0002-8836-3054" } ] }, "title": "Reconciling Archean organic-rich mudrocks with low primary productivity before the Great Oxygenation Event", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon burial; early biosphere; carbon cycle; Precambrian; primary productivity", "note": "

© 2025 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).

\n\n

We thank Lee Kump and an anonymous reviewer for their insightful suggestions which improved the manuscript. This work was made possible with support from the David and Lucile Packard Foundation (W.W.F.), the Australian Research Council (B.R.), the Schwartz Reisman Collaborative Science Program (N.L. and W.W.F.), Caltech Resnick Institute (S.S.Z. and W.W.F.), and Caltech Center for Comparative Planetary Evolution (W.W.F.).

\n\n

N.L., B.R., and W.W.F. designed research; N.L., B.R., J.-W.Z., S.S.Z., T.M.P., Y.M.B.-O., and W.W.F. performed research; N.L., B.R., J.-W.Z., and W.W.F. analyzed data; and N.L., B.R., and W.W.F. wrote the paper.

\n\n

The data that support the findings of this study are compiled in Datasets S1–S3, and are openly available in Figshare: https://doi.org/10.6084/m9.figshare.28022513.

\n

 

\n\n

Supporting information:

\n

Appendix 01 (PDF)

\n

Dataset S01 (CSV)

\n

Dataset S02 (CSV)

\n

Dataset S01 (CSV)

", "abstract": "
The organic carbon content of ancient rocks provides a fundamental record of the biosphere on early Earth. For over 50 y, the high organic content of Archean (>2.5 Ga) mudrocks has puzzled geologists and evolutionary biologists, because high biological primary productivity was unexpected for the nascent biosphere before the rise of O2. Here, we took a different approach to resolve this apparent paradox, by studying the accumulation rates of Archean organic-rich mudrocks. We evaluated the sedimentation rates of three sections of the Mount McRae Shale and Jeerinah Formation (2.68 to 2.48 Ga, Pilbara Craton, Australia) with new and recently published U–Pb zircon ages from intraformational ash beds. For comparison, we compiled Phanerozoic (<500 Ma) data from comparable depositional settings and developed an idealized model that considers the sedimentation rates for predicting rock organic content. We found that organic-rich Archean mudrocks were deposited under exceptionally low sedimentation rates (~1 m/Ma), in sharp contrast to organic-rich rocks from the Phanerozoic Eon (10 to 100 m/Ma). Constrained by observations, model results indicated that the Archean data reflect low primary productivity (~100-fold lower than during the Phanerozoic) and enhanced preservation under anoxic conditions, with the principal control on organic carbon content provided by dilution with inorganic sediment. Thus, the high organic carbon content which is typically attributed to high productivity instead reflects slow accumulation, high preservation, and minimal inorganic dilution—reconciling the geological evidence with a slow carbon cycle cadence during Archean time.
\n\n
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\n
", "date": "2025-01-14", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "122", "number": "2", "publisher": "National Academy of Sciences", "pagerange": "e2417673121", "issn": "0027-8424", "official_url": "https://authors.library.caltech.edu/records/zabhn-2mt61", "funders": { "items": [ {}, {}, { "grant_number": "Schwartz Reisman Collaborative Science Program" }, {} ] }, "local_group": { "items": [ { "id": "Caltech-Center-for-Comparative-Planetary-Evolution" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2417673121", "primary_object": { "basename": "lotem-et-al-2025-reconciling-archean-organic-rich-mudrocks-with-low-primary-productivity-before-the-great-oxygenation.pdf", "url": "https://authors.library.caltech.edu/records/zabhn-2mt61/files/lotem-et-al-2025-reconciling-archean-organic-rich-mudrocks-with-low-primary-productivity-before-the-great-oxygenation.pdf" }, "related_objects": [ { "basename": "pnas.2417673121.sapp.pdf", "url": "https://authors.library.caltech.edu/records/zabhn-2mt61/files/pnas.2417673121.sapp.pdf" }, { "basename": "pnas.2417673121.sd01.csv", "url": "https://authors.library.caltech.edu/records/zabhn-2mt61/files/pnas.2417673121.sd01.csv" }, { "basename": "pnas.2417673121.sd02.csv", "url": "https://authors.library.caltech.edu/records/zabhn-2mt61/files/pnas.2417673121.sd02.csv" }, { "basename": "pnas.2417673121.sd03.csv", "url": "https://authors.library.caltech.edu/records/zabhn-2mt61/files/pnas.2417673121.sd03.csv" } ], "pub_year": "2025", "author_list": "Lotem, Noam; Rasmussen, Birger; et al." }, { "id": "https://authors.library.caltech.edu/records/ayxth-zw363", "eprint_status": "archive", "datestamp": "2025-01-03 19:28:46", "lastmod": "2025-01-03 22:50:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Knapp-Taylor", "name": { "family": "Knapp", "given": "Taylor" }, "orcid": "0000-0001-8474-4143" }, { "id": "Chatziioannou-K", "name": { "family": "Chatziioannou", "given": "Katerina" }, "orcid": "0000-0002-5833-413X" }, { "name": { "family": "Pfeiffer", "given": "Harald" }, "orcid": "0000-0001-9288-519X" }, { "id": "Scheel-M-A", "name": { "family": "Scheel", "given": "Mark" }, "orcid": "0000-0001-6656-9134" }, { "name": { "family": "Kidder", "given": "Lawrence E." }, "orcid": "0000-0001-5392-7342" } ] }, "title": "Parameter control for eccentric, precessing binary black hole simulations with SpEC", "ispublished": "pub", "full_text_status": "public", "keywords": "General relativity; Gravitational waves; Numerical simulations in gravitation & astrophysics", "note": "

© 2025 American Physical Society.

\n\n

The computations presented here were conducted partly in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. Computations for this work were also partly performed with the Wheeler cluster at Caltech. We thank Saul Teukolsky for discussions on fitting methods and the SXS group for advice on using SpEC. This work was supported by the Sherman Fairchild Foundation, and by NSF Grants No. PHY-2309211, No. PHY-2309231, and No. OAC-2209656 at Caltech.

\n\n

The data that support the findings of this article are not publicly available because they are owned by a third party and the terms of use prevent public distribution. The data are available from the authors upon reasonable request.

", "abstract": "

Numerical relativity simulations of merging black holes provide the most accurate description of the binary dynamics and the emitted gravitational wave signal. However, practical considerations such as imperfect initial data and initial parameters mean that achieving target parameters, such as the orbital eccentricity or the black hole spin directions, at the beginning of the usable part of the simulation is challenging. In this paper, we devise a method to produce simulations with specific target parameters, namely the Keplerian orbital parameters—eccentricity, semimajor axis, mean anomaly—and the black hole spin vectors using SpEC. The method is an extension of the current process for achieving vanishing eccentricity and it is based on a parameter control loop that iteratively numerically evolves the system, fits the orbit with analytical post-Newtonian equations, and calculates updated input parameters. Through SpEC numerical simulations, we demonstrate and \ud835\udcaa\u2061(degree) convergence for the orbital eccentricity and the spin directions respectively in ≤ 7 iterations. These tests extend to binaries with mass ratios \ud835\udc5e ≤ 3, eccentricities \ud835\udc52 ≤ 0.65, and spin magnitudes |\ud835\udf12| ≤ 0.75. Our method for controlling the orbital and spin parameters of numerical simulations can be used to produce targeted simulations in sparsely covered regions of the parameter space or study the dynamics of relativistic binaries.

", "date": "2025-01-02", "date_type": "published", "publication": "Physical Review D", "volume": "111", "number": "2", "publisher": "American Physical Society", "pagerange": "024003", "issn": "2470-0010", "official_url": "https://authors.library.caltech.edu/records/ayxth-zw363", "funders": { "items": [ {}, {}, { "grant_number": "PHY-2309211" }, { "grant_number": "PHY-2309231" }, { "grant_number": "OAC-2209656" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "LIGO" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevd.111.024003", "primary_object": { "basename": "PhysRevD.111.024003.pdf", "url": "https://authors.library.caltech.edu/records/ayxth-zw363/files/PhysRevD.111.024003.pdf" }, "pub_year": "2025", "author_list": "Knapp, Taylor; Chatziioannou, Katerina; et al." }, { "id": "https://authors.library.caltech.edu/records/zzkrh-yvx37", "eprint_status": "archive", "datestamp": "2025-05-29 15:21:53", "lastmod": "2025-07-03 19:18:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Miller-Kimberly-Litwin", "name": { "family": "Miller", "given": "Kimberly Litwin" }, "orcid": "0000-0002-4299-9006" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Mud cohesion governs unvegetated meander migration rates and deposit architecture", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 Geological Society of America.

\n\n
\n
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The authors thank Alex Beer, Austin Chadwick, Jan de Leeuw, Emily Geyman, Hemani Kalucha, Evelyn Lamb, Tien-Hao Liao, Freya Morris, Justin Ngheim, Zhongheng Sun, and Tom Ulizio for field assistance. We thank Sinéad Lyster, Alex Whittaker, and one anonymous reviewer for constructive comments that improved this manuscript. This work was conducted under National Park Service Permits DEVA-2018-SCI-0021, DEVA-2019-SCI-0025, and DEVA-2021-SCI-0003; and we would like to thank Ambre Chadouin, Richard Friese, Jane Lakeman, and Kevin Wilson for overseeing permitting and activities in Death Valley National Park. M.M. Douglas acknowledges support from the National Defense Science and Engineering Graduate Fellowship and the Resnick Sustainability Institute as well as the National Center for Airborne Laser Mapping (NCALM) Seed Proposal Program, which supported lidar collection.

\n
\n
\n\n

Supplemental Material. Supplemental Texts S1–S2.2, Figures S1–S3, Movies S1–S3, and Tables S1–S4. Please visit Supplemental Material: Mud cohesion governs unvegetated meander migration rates and deposit architecturehttps://doi.org/10.1130/GSAB.S.26090536 to access the supplemental material.

", "abstract": "
\n\n\n

Vegetation is thought to be a main source of riverbank cohesion, enabling meandering and a deposit architecture characterized by sandy channel belts isolated in mudstone. However, early Earth and Mars had meandering rivers without vegetation, implying that other sources of bank strength can allow meandering with potentially different deposit characteristics. Here we studied the Amargosa River in Death Valley, California, USA, as a modern analog of meandering rivers without vegetation. We monitored flow and erosion at two bends and used radiocarbon dating of strandlines to quantify flood frequency. We also sampled cutbank mud and constrained an erosion theory using flume experiments. Cutbank erosion occurred for floods with >2 yr recurrence intervals, and 18 cm occurred for an ~6 yr reoccurrence, bankfull event. Mud set the rate of meander migration: salt crusts rapidly and completely dissolved during floods, vegetation was absent, and mud entrainment theory matched observed erosion rates. Flood-frequency analysis showed that most bank erosion occurs at flows below bankfull, challenging the threshold channel hypothesis. We used meander migration rates to constrain the time scale of channel-belt formation and compared it to the time scale of avulsion. These calculations, combined with floodplain facies mapping and core sedimentology, indicated a likely deposit architecture of sandy point bar accretion sets intermixed with muddy overbank facies. This deposit architecture is characteristic of vegetated meandering rivers, but due to muddy banks, occurred for the Amargosa River in the absence of plants.

\n\n
", "date": "2025-01-01", "date_type": "published", "publication": "Geological Society of America Bulletin", "volume": "137", "number": "1-2", "publisher": "Geological Society of America", "pagerange": "522-540", "issn": "0016-7606", "official_url": "https://authors.library.caltech.edu/records/zzkrh-yvx37", "funders": { "items": [ { "grant_number": "-" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1130/b37315.1", "primary_object": { "basename": "B37315_SuppMat.pdf", "url": "https://authors.library.caltech.edu/records/zzkrh-yvx37/files/B37315_SuppMat.pdf" }, "related_objects": [ { "basename": "B37315_MovieS2.mp4", "url": "https://authors.library.caltech.edu/records/zzkrh-yvx37/files/B37315_MovieS2.mp4" }, { "basename": "B37315_MovieS3.mp4", "url": "https://authors.library.caltech.edu/records/zzkrh-yvx37/files/B37315_MovieS3.mp4" }, { "basename": "B37315_MovieS1.mp4", "url": "https://authors.library.caltech.edu/records/zzkrh-yvx37/files/B37315_MovieS1.mp4" } ], "pub_year": "2025", "author_list": "Douglas, Madison M.; Miller, Kimberly Litwin; et al." }, { "id": "https://authors.library.caltech.edu/records/n0egz-t9y05", "eprint_status": "archive", "datestamp": "2025-03-04 23:27:35", "lastmod": "2026-01-14 12:32:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Magistro-Beatrice", "name": { "family": "Magistro", "given": "Beatrice" }, "orcid": "0000-0001-7423-3577" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. M. (Michael)" }, "orcid": "0000-0002-8113-4451" } ] }, "title": "Appealing to Independents: information on negative externalities increases support for environmental corrective taxes", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon tax; climate change; negative externalities; social welfare", "note": "

Rights managed by Taylor & Francis.

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The work was supported by the Resnick Sustainability Institute.

\n\n

The data collection and analysis procedures were reviewed by the Institute Research Board at the California Institute of Technology and were ruled exempt (IR22–1220). It is exempt under 45 C.F.R. § 46.104(d)(2)(i),(ii) as it is research using survey procedures where the identity of the subjects cannot be readily ascertained. The interviewing and survey administration are conducted by YouGov, which provides us with a dataset with no identifying information for the subjects. In other words, we receive data that is completely anonymized.

\n\n

Supplemental data for this article can be accessed online at https://doi.org/10.1080/09644016.2024.2439686

", "abstract": "Climate change requires urgent global action, but efforts to implement solutions like a carbon tax face deep political polarization, particularly in the United States. This study explores how framing corrective taxes as welfare-enhancing tools might influence public support. Through a pre-registered survey experiment, we manipulate information about the economic benefits of corrective taxes that address negative externalities, assessing their impact on support across political groups. Our findings reveal that this information significantly increases the belief across all groups that the benefits of a carbon tax outweigh its costs and makes increasing social welfare a more salient goal. While Independents show significant positive shifts in support for carbon taxes, moving from weakly negative to weakly positive stances, Republicans remain largely unmoved, likely due to entrenched ideological resistance.", "date": "2024-12-15", "date_type": "published", "publication": "Environmental Politics", "volume": "34", "number": "7", "publisher": "Informa UK Limited", "pagerange": "1300-1322", "issn": "0964-4016", "official_url": "https://authors.library.caltech.edu/records/n0egz-t9y05", "funders": { "items": [ {} ] }, "local_group": { "items": [ { "id": "Division-of-the-Humanities-and-Social-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1080/09644016.2024.2439686", "primary_object": { "basename": "fenp_a_2439686_sm6270.pdf", "url": "https://authors.library.caltech.edu/records/n0egz-t9y05/files/fenp_a_2439686_sm6270.pdf" }, "pub_year": "2024", "author_list": "Magistro, Beatrice and Alvarez, R. M. (Michael)" }, { "id": "https://authors.library.caltech.edu/records/99hqa-f7k65", "eprint_status": "archive", "datestamp": "2025-02-11 18:48:47", "lastmod": "2025-02-12 00:13:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Ziyi", "name": { "family": "Wang", "given": "Ziyi" }, "orcid": "0000-0003-0811-921X" }, { "id": "Quine-Cullen-Mackenzie", "name": { "family": "Quine", "given": "Cullen M." }, "orcid": "0000-0002-7301-0969" }, { "id": "Saunders-Claire-Nicole", "name": { "family": "Saunders", "given": "Claire N." }, "orcid": "0000-0001-7973-3722" }, { "id": "Bernal-Choban-Camille-Marie", "name": { "family": "Bernal-Choban", "given": "Camille M." }, "orcid": "0000-0001-7550-3153" }, { "id": "Ahn-C-C", "name": { "family": "Ahn", "given": "Channing C." }, "orcid": "0000-0003-3038-6509" }, { "id": "Fultz-B", "name": { "family": "Fultz", "given": "Brent T." }, "orcid": "0000-0002-6364-8782" } ] }, "title": "Kr Adsorption in Porous Carbons: Temperature-Dependent Experimental and Computational Studies", "ispublished": "pub", "full_text_status": "public", "keywords": "Adsorption; Energy; Enthalpy; Layers; Materials", "note": "

© 2024, American Chemical Society

\n\n

This work used resources from the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under Contract DE-AC02-05CH11231. Partial support of this work through the Resnick Sustainability Institute is gratefully acknowledged.

\n\n

In this article, the extensive properties shown with lowercase letters are for one particle rather than for 1 mole.

\n\n

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/acs.langmuir.4c02194.

\n", "abstract": "The temperature dependence of the adsorption energy of krypton adsorption on activated carbon materials was studied by experiment and simulation. Adsorption isotherms were measured at temperatures from 250 to 330 K and analyzed with Henry's law. The adsorption energy determined from these measurements was found to weaken by more than 10% in this range. Slit pore widths for simulations in this work were modeled by the removal of integral numbers of planes in graphite. Vibrational dynamics of the krypton adsorbate and the carbon atom adsorbent were calculated with the stochastic temperature-dependent effective potential (sTDEP) method, using energetics from density functional theory (DFT) with the many-body dispersion energy method (MBD). Thermal displacements of carbon atoms had a negligible effect on the adsorption energy. The width of the slit pore had the greatest effect on the surface dynamics and the energies of the adsorbate atoms at different temperatures. Assuming a distribution of pore widths, the Boltzmann distribution of site occupancies causes a large weakening of the thermally averaged adsorption energy at higher temperatures.", "date": "2024-12-10", "date_type": "published", "publication": "Langmuir", "volume": "40", "number": "49", "publisher": "American Chemical Society", "pagerange": "25793\u201325799", "issn": "0743-7463", "official_url": "https://authors.library.caltech.edu/records/99hqa-f7k65", "funders": { "items": [ {}, { "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.langmuir.4c02194", "primary_object": { "basename": "la4c02194_si_001.pdf", "url": "https://authors.library.caltech.edu/records/99hqa-f7k65/files/la4c02194_si_001.pdf" }, "pub_year": "2024", "author_list": "Wang, Ziyi; Quine, Cullen M.; et al." }, { "id": "https://authors.library.caltech.edu/records/csgx3-wnh76", "eprint_status": "archive", "datestamp": "2024-12-03 17:42:20", "lastmod": "2024-12-03 17:42:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jones-Nathan-D", "name": { "family": "Jones", "given": "Nathan D." }, "orcid": "0000-0002-0911-4616" }, { "id": "Moure-Adrian", "name": { "family": "Moure", "given": "Adrian" }, "orcid": "0000-0001-9807-0039" }, { "id": "Fu-Xiaojing-Ruby", "name": { "family": "Fu", "given": "Xiaojing" }, "orcid": "0000-0001-7120-704X" } ] }, "title": "Pattern formation of freezing infiltration in porous media", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate research; Fingering instability; Flows in porous media; Pattern formation; Reacting multiphase flows", "note": "

©2024 American Physical Society.

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The authors acknowledge the partial support from the Resnick Sustainability Institute at California Institute of Technology and from the U.S. National Science Foundation under Grant No. EAR-2243631.

", "abstract": "

Gravity-driven infiltration of liquid water into unsaturated porous media can be a spatially heterogeneous process due to the gravity fingering instability. When such infiltration occurs in a subfreezing porous medium, liquid water can readily freeze, leading to both the removal of liquid water available for transport and a reduction in local permeability. As a result of the coupling between gravity fingering and freezing, macroscopic frozen structures can form that record the shape and history of the wetting front. These structures have been observed in the field in terrestrial snowpack and glacial firn layers and are believed to have profound impacts on how liquid water and its accompanying thermal content distribute during infiltration. However, a more detailed physics-based understanding of freezing infiltration has been missing. In this work, we use a thermodynamic nonequilibrium infiltration model to investigate the emergence of refrozen structures during water infiltration into an initially homogeneous and subfreezing porous medium. From scaling analysis, we recover the relevant nondimensional groups that govern the physics of the freezing infiltration process. We identify two key mechanisms caused by freezing that reduce the effective infiltration rate, calculated as the maximum depth of infiltration per elapsed time. In the first mechanism, the effective infiltrate rate decreases because a portion of the liquid water is consumed due to freezing, and such an effect can be well quantified by the freezing Damköhler number. For the second mechanism, we report on a new phenomenon termed secondary fingering, where new flow paths are established in between the primary infiltration channels. We find that secondary fingering reduces the degree of flow channelization and thus weakens the effective rate of infiltration via flow field homogenization. Finally, we identify a regime under high Damköhler number in which freezing-induced permeability reduction completely clogs flow.

", "date": "2024-12-02", "date_type": "published", "publication": "Physical Review Fluids", "volume": "9", "number": "12", "publisher": "American Physical Society", "pagerange": "123802", "issn": "2469-990X", "official_url": "https://authors.library.caltech.edu/records/csgx3-wnh76", "funders": { "items": [ {}, { "grant_number": "EAR-2243631" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevfluids.9.123802", "primary_object": { "basename": "PhysRevFluids.9.123802.pdf", "url": "https://authors.library.caltech.edu/records/csgx3-wnh76/files/PhysRevFluids.9.123802.pdf" }, "pub_year": "2024", "author_list": "Jones, Nathan D.; Moure, Adrian; et al." }, { "id": "https://authors.library.caltech.edu/records/wqsch-1ea98", "eprint_status": "archive", "datestamp": "2025-03-04 22:54:46", "lastmod": "2025-03-04 22:54:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "id": "Dove-Lilian-Aja", "name": { "family": "Dove", "given": "Lilian A." }, "orcid": "0000-0001-8346-0034" }, { "id": "Flint-Ellie", "name": { "family": "Flint", "given": "Ellie" } }, { "name": { "family": "Lacour", "given": "Leo" }, "orcid": "0000-0003-1792-5969" }, { "name": { "family": "Boyd", "given": "Philip" }, "orcid": "0000-0001-7850-1911" } ] }, "title": "Interactions Between Multiple Physical Particle Injection Pumps in the Southern Ocean", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon export; Southern Ocean; submesoscale; biological pump; glider; mixed layer", "note": "

© 2024 The Author(s). This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

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We are grateful for the efforts of the full SOLACE field team as well as the captain and crew of the R/V Investigator. We extend particular thanks to Tyler Rohr who took on extra glider testing, deployment and troubleshooting responsibilities during the cruise due to COVID travel restrictions. The authors acknowledge helpful suggestions and conversations from Elizabeth, Shadwick, Tom Trull, Mara Freilich, and Alice Della Penna. AFT, LAD and EF were supported by the Resnick Sustainability Institute and the Ginkgo Foundation; LAD received additional support from an NSF Graduate Research Fellowship and a NOAA Climate & Global Change Postdoctoral Fellowship. EF's contributions were supported by a Summer Undergraduate Research Fellowship at Caltech. LL was supported by a European Union's Horizon 2020 Marie Sklodowska-Curie Grant (no. 892653). PWB was funded by the Australian Research Council by Laureate Fellowship FL160100131. This research was supported by a grant of sea time on RV Investigator from the CSIRO Marine National Facility (https://ror.org/01mae9353).

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Supporting Information S1: 2024GB008122-sup-0001-Supporting Information SI-S01.pdf

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Surface flux and forcing data is available through the Australian Ocean Data Network (IMOS, 2022) at https://imos.org.au/facility/deep-water-moorings/southern-ocean-time-series-observatory. Sea level anomaly and surface velocity products were produced and distributed by the Copernicus Marine 360 and Environment Monitoring Service (Copernicus Climate Change Service, 2018) and are available at https://data.marine.copernicus.eu/product/SEALEVEL_GLO_PHY_L4_MY_008_047/description. Finite-size Lyapunov Exponents were produced and distributed by AVISO+ (AVISO, 2022) and are available at https://www.aviso.altimetry.fr/en/data/products/value-added-products/fsle-finite-size-lyapunov-exponents.html.

\n

Glider data presented in this work has been uploaded to the NOAA National Centers for Environmental Information (NCEI) database (Thompson & Dove 2023) and is accessible at https://www.ncei.noaa.gov/archive/accession/0276999. Float data can be downloaded from the Argo Global Data Assembly Center (Argo, 2000) (ftp://ftp.ifremer.fr/ifremer/argo/). These data were collected and made freely available by the International Argo Program and the national programs that contribute to it (http://www.argo.ucsd.edu, https://www.ocean-ops.org). The Argo Program is part of the Global Ocean Observing System.

", "abstract": "

Contributions to the biological pump that arise from the physical circulation are referred to as physical particle injection pumps. A synthesized view of how these physical pumps interact with each other and other components of the biological pump does not yet exist. Here, observations from a quasi-Lagrangian float and an ocean glider, deployed in the Southern Ocean's Subantarctic Zone for one month during the spring bloom, offer insight into daily-to-monthly fluctuations in the mixed layer pump (MLP) and the eddy subduction pump (ESP). Estimated independently, each mechanism contributes intermittent export fluxes of roughly several hundred milligrams of particulate organic carbon (POC) per square meter per day. The glider-based estimates indicate sustained weekly periods of MLP export fluxes across the base of the mixed layer with a magnitude of ∼450±110 mg POC m−2 day−1. Potential export fluxes from the ESP, based on a mixed layer instability scaling, occasionally exceed 400 mg POC m−2 day−1, with export elevated due to both strong inferred vertical velocities and enhanced isopycnal slopes. Significant export fluxes from the ESP are localized to the edges of mesoscale eddies and to fronts, whereas the MLP acts more broadly due to the larger scales of atmospheric forcing. Regimes occur when MLP and ESP export fluxes can have either the same or opposite sign. Simple summation of fluxes from existing parameterizations of the two pumps likely misrepresents the total physical carbon flux. Insights into how mesoscale stirring and submesoscale velocities set POC vertical structure is a key target to reduce uncertainty in global carbon export fluxes.

", "date": "2024-12", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "38", "number": "12", "publisher": "American Geophysical Union", "pagerange": "e2024GB008122", "issn": "0886-6236", "official_url": "https://authors.library.caltech.edu/records/wqsch-1ea98", "funders": { "items": [ {}, { "grant_number": "-" }, { "grant_number": "-" }, { "grant_number": "-" }, { "grant_number": "892653" }, { "grant_number": "FL160100131" }, { "grant_number": "-" } ] }, "local_group": { "items": [ { "id": "Division-of-Engineering-and-Applied-Science" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2024gb008122", "primary_object": { "basename": "Global Biogeochemical Cycles - 2024 - Thompson - Interactions Between Multiple Physical Particle Injection Pumps in the.pdf", "url": "https://authors.library.caltech.edu/records/wqsch-1ea98/files/Global Biogeochemical Cycles - 2024 - Thompson - Interactions Between Multiple Physical Particle Injection Pumps in the.pdf" }, "related_objects": [ { "basename": "2024gb008122-sup-0001-supporting information si-s01.pdf", "url": "https://authors.library.caltech.edu/records/wqsch-1ea98/files/2024gb008122-sup-0001-supporting information si-s01.pdf" } ], "pub_year": "2024", "author_list": "Thompson, Andrew F.; Dove, Lilian A.; et al." }, { "id": "https://authors.library.caltech.edu/records/2tk1v-84j29", "eprint_status": "archive", "datestamp": "2024-11-08 19:32:52", "lastmod": "2025-02-12 00:17:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Hinton", "given": "Jasmine K." }, "orcid": "0000-0003-4417-462X" }, { "name": { "family": "Schacher", "given": "Daniel" }, "orcid": "0000-0002-4095-6635" }, { "id": "Lee-Wonseok", "name": { "family": "Lee", "given": "Wonseok" }, "orcid": "0000-0003-1077-0511" }, { "name": { "family": "Smith", "given": "G. Alexander" }, "orcid": "0000-0001-9701-1328" }, { "name": { "family": "Siska", "given": "Emily" } }, { "name": { "family": "Park", "given": "Changyong" }, "orcid": "0000-0002-3363-5788" }, { "name": { "family": "Ellison", "given": "Paul B." }, "orcid": "0000-0001-8852-9782" }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott K." }, "orcid": "0000-0003-3538-2259" }, { "name": { "family": "Schwartz", "given": "Craig P." }, "orcid": "0000-0002-4149-2684" }, { "name": { "family": "Lawler", "given": "Keith V." }, "orcid": "0000-0003-1087-5815" }, { "name": { "family": "Salamat", "given": "Ashkan" }, "orcid": "0000-0001-6556-7532" } ] }, "title": "Electronic topological transitions in cadmium under pressure studied via theoretical and experimental x-ray absorption spectroscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "Electronic structure; High-pressure studies; Phase transitions; Topological materials", "note": "

© 2024 American Physical Society.

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This work was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences under Award No. DE-SC0020303. Portions of this work were performed at HPCAT (Sector 16), Advanced Photon Source (APS), Argonne National Laboratory. HPCAT operations are supported by DOE-NNSA's Office of Experimental Sciences. The Advanced Photon Source is a U.S. DOE Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. D.S., C.P.S., and K.V.L. were supported by Chemical Sciences, Geosciences and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy under DOE Grant No. DE-SC-0023355. This research used resources of the National Energy Research Scientific Computing Center (NERSC), U.S. DOE Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231 using NERSC Awards No. BES-ERCAP0023039 and No. BES-ERCAP0023126. W.L. acknowledges support from the Korea Foundation for Advanced Studies. W.L. and S.K.C. were supported as part of Ensembles of Photosynthetic Nanoreactors (EPN), an Energy Frontiers Research Center funded by the U.S. DOE, Office of Science under Award No. DE-SC0023431. The exciton distribution calculations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. G. A. Smith contributed to this work while at the National High Magnetic Field Laboratory. The National High Magnetic Field Laboratory is supported by the National Science Foundation through NSF/DMR-2128556, the State of Florida, and the U.S. DOE.

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Supplemental Material:

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X-ray diffraction setup, lattice parameters and volume data tables, sample photos and measurements, cross sectional absorption maps of DAC samples, raw XRD and refinement example, additional representation of structural data collected via XRD and XAS, a discussion on XAS setup and verification of the energy calibration of the monochromator, EXAFS analysis and discussion, XANES analysis and discussion, additional representations of Fermi surface, partial density of states, additional exciton projection band plots, and experimental and computational Raman data.

\n

Raw data and analysis are provided in two zip files in the SM.

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JKH_Cd_ETT_SM.pdf

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Cd_ETT_raw_data_and_analysis.zip

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Cd_ETT_raw_data_and_analysis_part_II.zip

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", "abstract": "

An electronic topological transition (ETT) in cadmium below 1 GPa is investigated in situ with experimental x-ray absorption spectroscopy and projecting calculated core-valence excitons onto the band structure. These projections are a useful application of the Bethe-Salpeter equation approach that considers many-body effects. The method described herein can be used for systems that are otherwise difficult to probe in situ; therefore, it provides a generalizable approach to identifying and understanding ETTs under high pressure. Although pressure-induced ETTs are often probed using indirect structural responses, our own x-ray diffraction and Raman studies suggest a second-order structural transition around 3 GPa but are largely insensitive to or inconclusive for the previously studied ETT in this region.

", "date": "2024-11-15", "date_type": "published", "publication": "Physical Review B", "volume": "110", "number": "20", "publisher": "American Physical Society", "pagerange": "205118", "issn": "2469-9950", "official_url": "https://authors.library.caltech.edu/records/2tk1v-84j29", "funders": { "items": [ { "grant_number": "DE-SC0020303" }, { "grant_number": "DE-AC02-06CH11357" }, { "grant_number": "DE-SC-0023355" }, { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "BES-ERCAP0023039" }, { "grant_number": "BES-ERCAP0023126" }, {}, { "grant_number": "DE-SC0023431" }, {}, { "grant_number": "DMR-2128556" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevb.110.205118", "primary_object": { "basename": "PhysRevB.110.205118.pdf", "url": "https://authors.library.caltech.edu/records/2tk1v-84j29/files/PhysRevB.110.205118.pdf" }, "related_objects": [ { "basename": "Cd_ETT_raw_data_and_analysis_part_II.zip", "url": "https://authors.library.caltech.edu/records/2tk1v-84j29/files/Cd_ETT_raw_data_and_analysis_part_II.zip" }, { "basename": "Cd_ETT_raw_data_and_analysis.zip", "url": "https://authors.library.caltech.edu/records/2tk1v-84j29/files/Cd_ETT_raw_data_and_analysis.zip" }, { "basename": "JKH_Cd_ETT_SM.pdf", "url": "https://authors.library.caltech.edu/records/2tk1v-84j29/files/JKH_Cd_ETT_SM.pdf" } ], "pub_year": "2024", "author_list": "Hinton, Jasmine K.; Schacher, Daniel; et al." }, { "id": "https://authors.library.caltech.edu/records/2aqyk-e1m90", "eprint_status": "archive", "datestamp": "2024-12-13 00:13:17", "lastmod": "2025-02-12 00:16:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Adillon-Enric-H", "name": { "family": "Adillon", "given": "Enric H." }, "orcid": "0000-0001-8695-0637" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "A Carborane-Derived Proton-Coupled Electron Transfer Reagent", "ispublished": "pub", "full_text_status": "public", "keywords": "Bond dissociation free energy; Evolution reactions; PH; Reaction mechanisms; Redox reactions", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY-NC-ND 4.0 

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This work was supported by the Department of Energy Basic Enegy Sciences (DE-SC0019136). E.H.A. acknowledges the Resnick Sustainability Institute for support via a Cross-Resnick Fellowship and the Department of Defense for support via a National Defense Science and Engineering Graduate Fellowship. The Beckman Institute at Caltech Supports the X-ray Crystallography Facility. JCP acknowledges the Resnick Sustainability Institute for enabling facilities and the Dow Next Generation Fund for support of Caltech’s EPR facility.

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The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/jacs.4c09007.

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Accession Codes: Deposition Numbers 2367450–2367452 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via the joint Cambridge Crystallographic Data Centre (CCDC) and Fachinformationszentrum Karlsruhe Access Structures service.

", "abstract": "

Reagents capable of concerted proton–electron transfer (CPET) reactions can access reaction pathways with lower reaction barriers compared to stepwise pathways involving electron transfer (ET) and proton transfer (PT). To realize reductive multielectron/proton transformations involving CPET, one approach that has shown recent promise involves coupling a cobaltocene ET site with a protonated arylamine Brønsted acid PT site. This strategy colocalizes the electron/proton in a matter compatible with a CPET step and net reductive electrocatalysis. To probe the generality of such an approach a class of C,C′-diaryl-o-carboranes is herein explored as a conceptual substitute for the cobaltocene subunit, with an arylamine linkage still serving as a colocalized Brønsted base suitable for protonation. The featured o-carborane (PhCbPhN) can be reduced and protonated to generate an N–H bond with a weak effective bond dissociation free energy (BDFEeff) of 31 kcal/mol, estimated with measured thermodynamic data. This N–H bond is among the lowest measured element–H bonds for analyzed nonmetal compounds. Distinct solid-state crystal structures of the one- and two-electron reduced forms of diaryl-o-carboranes are disclosed to gain insight into their well-behaved redox characteristics. The singly reduced, protonated form of the diaryl-o-carborane can mediate multi-ET/PT reductions of azoarenes, diphenylfumarate, and nitrotoluene. In contrast to the aforementioned cobaltocene system, available mechanistic data disclosed herein support these reactions occurring by a rate-limiting ET step and not a CPET step. A relevant hydrogen evolution reaction (HER) reaction was also studied, with data pointing to a PT/ET/PT mechanism, where the reduced carborane core is itself highly stable to protonation.

", "date": "2024-11-06", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "146", "number": "44", "publisher": "American Chemical Society", "pagerange": "30204 - 30211", "issn": "0002-7863", "official_url": "https://authors.library.caltech.edu/records/2aqyk-e1m90", "funders": { "items": [ { "grant_number": "DE-SC0019136" }, { "grant_number": "-" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.4c09007", "primary_object": { "basename": "adillon-peters-2024-a-carborane-derived-proton-coupled-electron-transfer-reagent.pdf", "url": "https://authors.library.caltech.edu/records/2aqyk-e1m90/files/adillon-peters-2024-a-carborane-derived-proton-coupled-electron-transfer-reagent.pdf" }, "related_objects": [ { "basename": "ja4c09007_si_001.txt", "url": "https://authors.library.caltech.edu/records/2aqyk-e1m90/files/ja4c09007_si_001.txt" }, { "basename": "ja4c09007_si_002.pdf", "url": "https://authors.library.caltech.edu/records/2aqyk-e1m90/files/ja4c09007_si_002.pdf" } ], "pub_year": "2024", "author_list": "Adillon, Enric H. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/h6c5d-r0547", "eprint_status": "archive", "datestamp": "2025-01-07 18:52:16", "lastmod": "2025-07-03 17:04:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Geyman-Emily-C", "name": { "family": "Geyman", "given": "Emily C." }, "orcid": "0000-0003-4349-9350" }, { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Avouac-J-P", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Permafrost slows Arctic riverbank erosion", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate change; Geomorphology; Hydrology", "note": "

© 2024 Springer Nature Limited.

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We thank the Huslia Tribal Council for river and land access and S. Huffman and the Yukon River Inter-Tribal Watershed Council for field and logistical support. We also thank J. Anadu, R. Blankenship, K. Dunne, W. Fischer, Y. Ke, H. Dion-Kirschner, J. Magyar, E. Mutter, J. Nghiem, J. Reahl, R. Rugama-Montenegro, E. Seelen, I. Smith and J. West for help in the field and for fruitful discussions. Planet Labs provided the high-resolution PlanetScope imagery through their Education and Research Program. This work was supported by NSF Award 2127442, NSF Award 2031532, and Caltech’s Resnick Sustainability Institute. E.C.G. thanks the NSF Graduate Research Fellowships Program and the Fannie and John Hertz Foundation.

\n\n

E.C.G. and M.P.L. designed the study. M.M.D. and M.P.L. developed the early thermomechanical model. J.-P.A. advised the sub-pixel methodology. E.C.G. developed the sub-pixel methodology, performed the analysis and wrote the manuscript, with input from M.M.D., J.-P.A. and M.P.L.

\n\n

The Sentinel-2 satellite images used to extract the 2016–2022 migration rates shown in Fig. 1 are freely available from the European Space Agency on data portals such as the Copernicus Open Access Hub (https://scihub.copernicus.eu/). The PlanetScope images used for the seasonal time-series analysis (Fig. 3) are available from Planet Labs (https://www.planet.com). The stream gauge data in Extended Data Fig. 2 are available from the United States Geological Survey (https://waterdata.usgs.gov/nwis). The permafrost map used in Fig. 2 and Extended Data Fig. 10 is from ref. 32 and is made available by the United States Geological Survey (https://www.sciencebase.gov/catalog/item/5602ab5ae4b03bc34f5448b4). Our spatial measurements of riverbank erosion from the Sentinel-2 and PlanetScope time-series analysis (Figs. 1–3) are packaged on the NSF Arctic Data Center68: https://doi.org/10.18739/A2HM52M6Q. Our field observations of permafrost presence/absence (Extended Data Fig. 10) from summer 2018 and fall 2022 are published on the ESS-DIVE repository67 (https://doi.org/10.15485/2204419).

\n\n

Our methodology for measuring sub-pixel bank erosion, as well as our workflow for channel extraction and the measurement of channel morphometrics (width, radius of curvature, longitudinal distance and so on) (Fig. 1), is available on the NSF Arctic Data Center68: https://doi.org/10.18739/A2HM52M6Q. The code is written in MATLAB.

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Supplementary Information, including Supplementary Figs. 1–11, Supplementary Tables 1 and 2 and Supplementary References (PDF)

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Peer Review File (PDF)

", "abstract": "

The rate of river migration affects the stability of Arctic infrastructure and communities and regulates the fluxes of carbon, nutrients and sediment to the oceans. However, predicting how the pace of river migration will change in a warming Arctic has so far been stymied by conflicting observations about whether permafrost primarily acts to slow or accelerate river migration. Here we develop new computational methods that enable the detection of riverbank erosion at length scales 5–10 times smaller than the pixel size in satellite imagery, an innovation that unlocks the ability to quantify erosion at the sub-monthly timescales when rivers undergo their largest variations in water temperature and flow. We use these high-frequency observations to constrain the extent to which erosion is limited by the thermal condition of melting the pore ice that cements bank sediment, a requirement that will disappear when permafrost thaws, versus the mechanical condition of having sufficient flow to transport the sediment comprising the riverbanks, a condition experienced by all rivers. Analysis of high-resolution data from the Koyukuk River, Alaska, shows that the presence of permafrost reduces erosion rates by 47%. Using our observations, we calibrate and validate a numerical model that can be applied to diverse Arctic rivers. The model predicts that full permafrost thaw may lead to a 30–100% increase in the migration rates of Arctic rivers.

", "date": "2024-10-10", "date_type": "published", "publication": "Nature", "volume": "634", "number": "8033", "publisher": "Nature Publishing Group", "pagerange": "359-365", "issn": "0028-0836", "official_url": "https://authors.library.caltech.edu/records/h6c5d-r0547", "funders": { "items": [ { "grant_number": "RISE-2127442" }, { "grant_number": "EAR-2031532" }, {}, { "grant_number": "NSF Graduate Research Fellowship" }, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41586-024-07978-w", "primary_object": { "basename": "41586_2024_7978_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/h6c5d-r0547/files/41586_2024_7978_MOESM1_ESM.pdf" }, "pub_year": "2024", "author_list": "Geyman, Emily C.; Douglas, Madison M.; et al." }, { "id": "https://authors.library.caltech.edu/records/ejg0y-tna56", "eprint_status": "archive", "datestamp": "2024-10-10 23:37:58", "lastmod": "2024-10-10 23:37:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moure-Adrian", "name": { "family": "Moure", "given": "Adrian" }, "orcid": "0000-0001-9807-0039" }, { "id": "Fu-Xiaojing-Ruby", "name": { "family": "Fu", "given": "Xiaojing" }, "orcid": "0000-0001-7120-704X" } ] }, "title": "A Phase-Field Model for Wet Snow Metamorphism", "ispublished": "pub", "full_text_status": "public", "keywords": "ice; interfaces; nucleation; phase transitions; water", "note": "

© 2024 The Authors. Published by American Chemical Society.  This publication is licensed under CC-BY-NC-ND 4.0.

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The authors acknowledge the partial support from the Resnick Sustainability Institute at California Institute of Technology, the National Science Foundation under Grant No. EAR-2243631, and the ACS Petroleum Research Fund Doctoral New Investigator Grant No. 66867-DNI9. The authors also acknowledge insightful discussions with Dr. Quirine Krol.

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Equivalence to models of two-phase transition and additional details for numerical implementation (PDF).

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Published as part of Crystal Growth & Design special issue “Heterogeneous Drivers of Ice Formation”.

", "abstract": "

The microstructure of snow determines its fundamental properties such as mechanical strength, reflectivity, or thermo-hydraulic properties. Snow undergoes continuous microstructural changes due to local gradients in temperature, humidity, or curvature, in a process known as snow metamorphism. In this work, we focus on wet snow metamorphism, which occurs when the temperature is close to the melting point and involves phase transitions among liquid water, water vapor, and solid ice. We propose a pore-scale phase-field model that simultaneously captures the three relevant phase change phenomena: sublimation (deposition), evaporation (condensation), and melting (solidification). The phase-field formulation allows one to track the temperature evolution among the three phases and the water vapor concentration in the air. Our three-phase model recovers the corresponding two-phase transition model when one phase is not present in the system. 2D simulations of the model unveil the impact of humidity and temperature on the dynamics of wet snow metamorphism at the pore scale. We also explore the role of liquid melt content in controlling the dynamics of snow metamorphism in contrast to the dry regime before percolation onsets. The model can be readily extended to incorporate two-phase flow and may be the basis for investigating other problems involving water phase transitions in a vapor–solid–liquid system, such as airplane icing or thermal spray coating.

", "date": "2024-10-02", "date_type": "published", "publication": "Crystal Growth & Design", "volume": "24", "number": "19", "publisher": "American Chemical Society", "pagerange": "7808-7821", "issn": "1528-7483", "official_url": "https://authors.library.caltech.edu/records/ejg0y-tna56", "funders": { "items": [ {}, { "grant_number": "EAR-2243631" }, { "grant_number": "66867-DNI9" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.cgd.4c00539", "primary_object": { "basename": "moure-fu-2024-a-phase-field-model-for-wet-snow-metamorphism.pdf", "url": "https://authors.library.caltech.edu/records/ejg0y-tna56/files/moure-fu-2024-a-phase-field-model-for-wet-snow-metamorphism.pdf" }, "related_objects": [ { "basename": "cg4c00539_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ejg0y-tna56/files/cg4c00539_si_001.pdf" } ], "pub_year": "2024", "author_list": "Moure, Adrian and Fu, Xiaojing" }, { "id": "https://authors.library.caltech.edu/records/g01q4-pds09", "eprint_status": "archive", "datestamp": "2024-06-26 19:32:49", "lastmod": "2025-04-26 02:54:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sobaszek-Micha\u0142", "name": { "family": "Sobaszek", "given": "Micha\u0142" }, "orcid": "0000-0002-3180-9297" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Klimczuk-Tomasz", "name": { "family": "Klimczuk", "given": "Tomasz" }, "orcid": "0000-0002-7089-4631" }, { "id": "Micha\u0142owski-Pawe\u0142-P", "name": { "family": "Micha\u0142owski", "given": "Pawe\u0142 P." }, "orcid": "0000-0002-3299-4092" }, { "id": "Ryl-Jacek", "name": { "family": "Ryl", "given": "Jacek" }, "orcid": "0000-0002-0247-3851" }, { "id": "Rutkowski-Bogdan", "name": { "family": "Rutkowski", "given": "Bogdan" }, "orcid": "0000-0003-0974-6450" }, { "id": "Wang-Dongying", "name": { "family": "Wang", "given": "Dongying" }, "orcid": "0000-0002-9674-3532" }, { "id": "Li-Xinwei", "name": { "family": "Li", "given": "Xinwei" } }, { "id": "Bockrath-Marc", "name": { "family": "Bockrath", "given": "Marc" }, "orcid": "0000-0002-7000-1442" }, { "id": "Bogdanowicz-Robert", "name": { "family": "Bogdanowicz", "given": "Robert" }, "orcid": "0000-0002-7543-2620" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Unraveling the role of boron dimers in the electrical anisotropy and superconductivity in boron-doped diamond", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 Published by Elsevier.

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W.A.G acknowledges support from the NSF (CBET-2311117); this work used the Extreme Science and Engineering Discovery Environment (XSEDE) for DFT calculations, which is supported by the NSF grant number ACI-1548562; S.K. acknowledges support from the Resnick Sustainability Institute at Caltech. R.B. acknowledges the support of these studies from Gda\u0144sk University of Technology by the DEC-12/2023/IDUB/IV.2/EUROPIUM grant under the Europium Short-Term Outgoing Visits - ‘Excellence Initiative - Research University’ program. P.P.M. was supported by the National Centre for Research and Development, Poland, project No. LIDER/8/0055/L-12/20/NCBR/2021.

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Micha\u0142 Sobaszek: Writing – original draft, Visualization, Validation, Supervision, Methodology, Investigation, Formal analysis, Conceptualization. Soonho Kwon: Writing – original draft, Visualization, Investigation, Formal analysis. Tomasz Klimczuk: Writing – original draft, Investigation, Formal analysis. Pawe\u0142 P. Micha\u0142owski: Data curation, Formal analysis, Writing – original draft. Jacek Ryl: Writing – original draft, Investigation, Formal analysis. Bogdan Rutkowski: Writing – original draft, Investigation. Dongying Wang: Investigation. Xinwei Li: Investigation. Marc Bockrath: Writing – review & editing, Project administration, Investigation, Formal analysis. Robert Bogdanowicz: Writing – review & editing, Supervision, Project administration. William A. Goddard: Writing – review & editing, Writing – original draft, Supervision, Project administration, Investigation, Formal analysis.

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Supplementary data

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The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

", "abstract": "
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We use quantum mechanics (QM) to determine the states formed by B dopants in diamond. We find that isolated B sites prefer to form BB dimers and that the dimers pair up to form tetramers (BBCBB) that prefer to aggregate parallel to the (111) surface in the <110> direction, one double layer below the H-terminated surface double layer. These tetramers lead to metallic character (Mott metal Insulator Transition) with holes in the valence band near the Γ point and electrons in the BBCBB tetramer promoted band along the X direction. Our experiments find very significant anisotropy in the superconductivity for boron-doped diamond thin films prepared with Microwave Plasma Assisted Chemical Vapor Deposition using deuterium-rich plasma. This leads to much higher conductivity in the X direction than the Y direction, as predicted by the QM. This phase transition to the anomalous phase is linked with the emergence of boson quantum entanglement states behaving as a bosonic insulating state. These anisotropic superconducting properties of the diamond film might enable applications such as single-photon detectors. We expect that this formation of a dirty superconductivity state is related to the BBCBB tetramers found in our QM calculations.

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", "date": "2024-09", "date_type": "published", "publication": "Carbon", "volume": "228", "publisher": "Elsevier", "pagerange": "119337", "issn": "0008-6223", "official_url": "https://authors.library.caltech.edu/records/g01q4-pds09", "funders": { "items": [ { "grant_number": "CBET-2311117" }, { "grant_number": "ACI-1548562" }, {}, { "grant_number": "DEC-12/2023/IDUB/IV.2/EUROPIUM" }, { "grant_number": "LIDER/8/0055/L-12/20/NCBR/2021" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.carbon.2024.119337", "primary_object": { "basename": "1-s2.0-S0008622324005566-mmc1.docx", "url": "https://authors.library.caltech.edu/records/g01q4-pds09/files/1-s2.0-S0008622324005566-mmc1.docx" }, "pub_year": "2024", "author_list": "Sobaszek, Micha\u0142; Kwon, Soonho; et al." }, { "id": "https://authors.library.caltech.edu/records/21131-8bt66", "eprint_status": "archive", "datestamp": "2025-01-09 22:40:49", "lastmod": "2025-01-09 22:40:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Gonz\u00e1lez-Romero", "given": "Adolfo" }, "orcid": "0000-0003-0977-6019" }, { "name": { "family": "Gonz\u00e1lez-Fl\u00f3rez", "given": "Cristina" }, "orcid": "0000-0002-3603-3088" }, { "name": { "family": "Panta", "given": "Agnesh" }, "orcid": "0000-0002-7953-8334" }, { "name": { "family": "Yus-D\u00edez", "given": "Jes\u00fas" }, "orcid": "0000-0002-8124-1492" }, { "name": { "family": "C\u00f3rdoba", "given": "Patricia" }, "orcid": "0000-0003-0596-4354" }, { "name": { "family": "Alastuey", "given": "Andres" }, "orcid": "0000-0002-5453-5495" }, { "name": { "family": "Moreno", "given": "Natalia" }, "orcid": "0000-0003-1488-2561" }, { "name": { "family": "Hern\u00e1ndez-Chiriboga", "given": "Melani" } }, { "name": { "family": "Kandler", "given": "Konrad" }, "orcid": "0000-0002-8268-6557" }, { "name": { "family": "Klose", "given": "Martina" }, "orcid": "0000-0001-8190-3700" }, { "name": { "family": "Clark", "given": "Roger N." }, "orcid": "0000-0002-7021-1220" }, { "id": "Ehlmann-B-L", "name": { "family": "Ehlmann", "given": "Bethany L." }, "orcid": "0000-0002-2745-3240" }, { "id": "Greenberger-Rebecca-N", "name": { "family": "Greenberger", "given": "Rebecca N." }, "orcid": "0000-0003-1583-0261" }, { "id": "Keebler-Abigail-M", "name": { "family": "Keebler", "given": "Abigail M." } }, { "id": "Brodrick-Philip-G", "name": { "family": "Brodrick", "given": "Phil" }, "orcid": "0000-0001-9497-7661" }, { "id": "Green-Robert-O", "name": { "family": "Green", "given": "Robert" }, "orcid": "0000-0001-9447-3076" }, { "name": { "family": "Ginoux", "given": "Paul" }, "orcid": "0000-0003-3642-2988" }, { "name": { "family": "Querol", "given": "Xavier" }, "orcid": "0000-0002-6549-9899" }, { "name": { "family": "P\u00e9rez Garc\u00eda-Pando", "given": "Carlos" }, "orcid": "0000-0002-4456-0697" } ] }, "title": "Characterization of the particle size distribution, mineralogy, and Fe mode of occurrence of dust-emitting sediments from the Mojave Desert, California, USA", "ispublished": "pub", "full_text_status": "public", "note": "

© Author(s) 2024. This work is distributed under the Creative Commons Attribution 4.0 License.

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Published by Copernicus Publications on behalf of the European Geosciences Union.

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We thank Richard Reynolds and an anonymous reviewer for the helpful comments and suggestions to improve the manuscript.

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The field campaign and its associated research, including this work, were funded by the European Research Council under the Horizon 2020 Research and Innovation programme through the ERC Consolidator Grant FRAGMENT (grant agreement no. 773051) and the AXA Research Fund through the AXA Chair on Sand and Dust Storms at BSC. Cristina González-Flórez was supported by a PhD fellowship from the Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) grant 2020_FI B 00678. Konrad Kandler was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, grant nos. 264907654 and 416816480). Martina Klose received funding through the Helmholtz Association's Initiative and Networking Fund (grant agreement no. VH-NG-1533). We acknowledge the EMIT project, which is supported by the NASA Earth Venture Instrument program, under the Earth Science Division of the Science Mission Directorate. We are grateful to Claire Blaske and Sahil Azad for assistance with sampling in the Mojave National Preserve. Samples within the preserve were collected under permit MOJA-2022-SCI-0034. We thank Rose Pettiette at the BLM office in Needles, CA, for advice and for allowing sampling on BLM land. We thank Jason Wallace and Anne Kelly from CSU Desert Studies Center at Zzyzx for their support during the campaign. Bethany L. Ehlmann, Rebecca N. Greenberger, and Abigail M. Keebler thank the Resnick Sustainability Institute at Caltech for partial support. Without all of the people mentioned, the sampling campaign would not have been successfully feasible.

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This research has been supported by the European Research Council, EU H2020 (Consolidator Grant FRAGMENT, grant no. 773051); the AXA Research Fund (AXA Chair on Sand and Dust Storms BSC); the Agència de Gestió d'Ajuts Universitaris i de Recerca (grant no. 2020_FI B 00678); the Deutsche Forschungsgemeinschaft (grant nos. 264907654 and 416816480); the Helmholtz Association (grant no. VH-NG-1533); and the Earth Sciences Division (NASA Earth Venture Instrument – Science Mission Directorate).

The article processing charges for this open-access publication were covered by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

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Sample permits were obtained by BLE, RNG, and AMK. The samples were collected by CPGP, AGR, AMK, RNG, and XQ and analysed by AGR, MHC, and NM. EMIT mineralogy maps we produced by RG, PB, and RNC. PG provided the FoO map. AGR analysed the data and wrote of the original draft manuscript, supervised by CPGP and XQ. CPGP and XQ re-edited the manuscript and all authors contributed to data discussion, review, and paper finalization.

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Data used in this paper are given in the main paper itself and in the Supplement. If needed, data are also available upon request by emailing the authors.

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The Tetracorder code used in this paper is provided at https://github.com/PSI-edu/spectroscopy-tetracorder by Clark (2023).

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The supplement related to this article is available online at: https://doi.org/10.5194/acp-24-9155-2024-supplement.

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At least one of the (co-)authors is a member of the editorial board of Atmospheric Chemistry and Physics. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare.

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This paper was edited by Stelios Kazadzis and reviewed by Richard Reynolds and one anonymous referee.

", "abstract": "
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Constraining dust models to understand and quantify the effect of dust upon climate and ecosystems requires comprehensive analyses of the physiochemical properties of dust-emitting sediments in arid regions. Building upon previous studies in the Moroccan Sahara and Iceland, we analyse a diverse set of crusts and aeolian ripples (n=55) from various potential dust-emitting basins within the Mojave Desert, California, USA. Our focus is on characterizing the particle size distribution (PSD), mineralogy, aggregation/cohesion state, and Fe mode of occurrence. Our results show differences in fully and minimally dispersed PSDs, with crusts exhibiting average median diameters of 92 and 37 µm, respectively, compared to aeolian ripples with 226 and 213 µm, respectively. Mineralogical analyses unveiled strong variations between crusts and ripples, with crusts being enriched in phyllosilicates (24 % vs. 7.8 %), carbonates (6.6 % vs. 1.1 %), Na salts (7.3 % vs. 1.1 %), and zeolites (1.2 % and 0.12 %) and ripples being enriched in feldspars (48 % vs. 37 %), quartz (32 % vs. 16 %), and gypsum (4.7 % vs. 3.1 %). The size fractions from crust sediments display a homogeneous mineralogy, whereas those of aeolian ripples display more heterogeneity, mostly due to different particle aggregation. Bulk Fe content analyses indicate higher concentrations in crusts (3.0 ± 1.3 wt %) compared to ripples (1.9 ± 1.1 wt %), with similar proportions in their Fe mode of occurrence: nano-sized Fe oxides and readily exchangeable Fe represent ∼1.6 %, hematite and goethite ∼15 %, magnetite/maghemite ∼2.0 %, and structural Fe in silicates ∼80 % of the total Fe. We identified segregation patterns in the PSD and mineralogy differences in Na salt content within the Mojave basins, which can be explained by sediment transportation dynamics and precipitates due to groundwater table fluctuations described in previous studies in the region. Mojave Desert crusts show similarities with previously sampled crusts in the Moroccan Sahara in terms of the PSD and readily exchangeable Fe yet exhibit substantial differences in mineralogical composition, which should significantly influence the characteristic of the emitted dust particles.

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", "date": "2024-08-22", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "24", "number": "16", "publisher": "European Geosciences Union", "pagerange": "9155-9176", "issn": "1680-7324", "official_url": "https://authors.library.caltech.edu/records/21131-8bt66", "funders": { "items": [ { "grant_number": "773051" }, { "grant_number": "AXA Chair on Sand and Dust Storms" }, { "grant_number": "2020_FI B 00678" }, { "grant_number": "264907654" }, { "grant_number": "416816480" }, { "grant_number": "VH-NG-1533" }, { "grant_number": "NASA Earth Venture Instrument" }, { "grant_number": "CSIC Open Access Publication Support Initiative" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.5194/acp-24-9155-2024", "primary_object": { "basename": "acp-24-9155-2024.pdf", "url": "https://authors.library.caltech.edu/records/21131-8bt66/files/acp-24-9155-2024.pdf" }, "related_objects": [ { "basename": "acp-24-9155-2024-supplement.pdf", "url": "https://authors.library.caltech.edu/records/21131-8bt66/files/acp-24-9155-2024-supplement.pdf" }, { "basename": "egusphere-2024-434.pdf", "url": "https://authors.library.caltech.edu/records/21131-8bt66/files/egusphere-2024-434.pdf" }, { "basename": "egusphere-2024-434-supplement.pdf", "url": "https://authors.library.caltech.edu/records/21131-8bt66/files/egusphere-2024-434-supplement.pdf" } ], "pub_year": "2024", "author_list": "Gonz\u00e1lez-Romero, Adolfo; Gonz\u00e1lez-Fl\u00f3rez, Cristina; et al." }, { "id": "https://authors.library.caltech.edu/records/qaawk-1qa86", "eprint_status": "archive", "datestamp": "2025-02-24 21:50:25", "lastmod": "2025-02-24 21:50:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shen-Zhichao", "name": { "family": "Shen", "given": "Zhichao" }, "orcid": "0000-0003-0458-5264" }, { "id": "Yang-Yan", "name": { "family": "Yang", "given": "Yan" }, "orcid": "0000-0002-6105-2918" }, { "id": "Fu-Xiaojing-Ruby", "name": { "family": "Fu", "given": "Xiaojing" }, "orcid": "0000-0001-7120-704X" }, { "id": "Adams-Kyra-H", "name": { "family": "Adams", "given": "Kyra H." }, "orcid": "0000-0002-9759-2019" }, { "id": "Biondi-Ettore", "name": { "family": "Biondi", "given": "Ettore" }, "orcid": "0000-0002-3305-0982" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" } ] }, "title": "Fiber-optic seismic sensing of vadose zone soil moisture dynamics", "ispublished": "pub", "full_text_status": "public", "keywords": "Geophysics; Hydrology; Seismology", "note": "

© The Author(s) 2024.

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This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

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We thank Santiago G. Solazzi for discussions on rock physics modeling from soil moisture to dv/v. This study is supported by the National Science Foundation CAREER #1848166 and the Resnick Institute of Sustainability. We are grateful to the field and technical support from Martin Karrrenbach, Lisa LaFlame, Vlad Bogdanov of Optasense Inc., Thomas Coleman of Silixa Inc., and Andrew Klesh of Jet Propulsion Laboratory. We thank the California Broadband Cooperative and JPL for providing access to the Digital 395 telecommunication fibers. Z.S. also thanks the support from the Weston Howland Jr. Postdoctoral Scholar Program at Woods Hole Oceanographic Institution.

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These authors contributed equally: Zhichao Shen, Yan Yang.

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Z.S. and Z.Z. conceptualized this study. Z.S., Y.Y., X.F., and Z.Z. developed the methodology. Z.S. and Y.Y. processed the data, and conducted the investigations with X.F., K.H.A., E.B., and Z.Z. together. Z.S. and Y.Y. contributed to the visualization. E.B. and Y.Y. contributed to the data management. Z.S. and Y.Y. drafted the original manuscript, and all the authors reviewed, edited, and refined the manuscript.

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The cross-correlation product and multi-frequency dv/v generated in this study have been deposited in Zenodo under the accession code https://doi.org/10.5281/zenodo.12617908. The precipitation data used in this study are available in the California Nevada River Forecast Center under accession code https://www.cnrfc.noaa.gov/arc_search.php. The groundwater well data used in this study are available in the Indian Wells Valley Groundwater Authority under accession code https://iwvgsp.com/. The surface temperature and surface soil moisture data used in this study are available from the National Snow and Ice Data Center under accession code https://nsidc.org/data/smap/data. Source data are provided in this paper.

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The GPU-based ambient noise cross-correlation code can be downloaded from https://github.com/zhichaoshen40/DAS_CC_GPU.git.

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Supplementary Information

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Peer Review File

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Source Data

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", "abstract": "

Vadose zone soil moisture is often considered a pivotal intermediary water reservoir between surface and groundwater in semi-arid regions. Understanding its dynamics in response to changes in meteorologic forcing patterns is essential to enhance the climate resiliency of our ecological and agricultural system. However, the inability to observe high-resolution vadose zone soil moisture dynamics over large spatiotemporal scales hinders quantitative characterization. Here, utilizing pre-existing fiber-optic cables as seismic sensors, we demonstrate a fiber-optic seismic sensing principle to robustly capture vadose zone soil moisture dynamics. Our observations in Ridgecrest, California reveal sub-seasonal precipitation replenishments and a prolonged drought in the vadose zone, consistent with a zero-dimensional hydrological model. Our results suggest a significant water loss of 0.25 m/year through evapotranspiration at our field side, validated by nearby eddy-covariance based measurements. Yet, detailed discrepancies between our observations and modeling highlight the necessity for complementary in-situ validations. Given the escalated regional drought risk under climate change, our findings underscore the promise of fiber-optic seismic sensing to facilitate water resource management in semi-arid regions.

", "date": "2024-08-05", "date_type": "published", "publication": "Nature Communications", "volume": "15", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "6432", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/qaawk-1qa86", "funders": { "items": [ { "grant_number": "EAR-1848166" }, {}, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" } ] }, "doi": "10.1038/s41467-024-50690-6", "primary_object": { "basename": "s41467-024-50690-6.pdf", "url": "https://authors.library.caltech.edu/records/qaawk-1qa86/files/s41467-024-50690-6.pdf" }, "related_objects": [ { "basename": "41467_2024_50690_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/qaawk-1qa86/files/41467_2024_50690_MOESM1_ESM.pdf" }, { "basename": "41467_2024_50690_MOESM3_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/qaawk-1qa86/files/41467_2024_50690_MOESM3_ESM.xlsx" } ], "pub_year": "2024", "author_list": "Shen, Zhichao; Yang, Yan; et al." }, { "id": "https://authors.library.caltech.edu/records/nzaqm-dsz57", "eprint_status": "archive", "datestamp": "2025-07-24 23:09:13", "lastmod": "2025-07-24 23:09:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Smith-Magdalene-I", "name": { "family": "Smith", "given": "Magdalene I." }, "orcid": "0009-0002-9170-7222" }, { "id": "Ke-Yutian", "name": { "family": "Ke", "given": "Yutian" }, "orcid": "0000-0002-9098-9419" }, { "id": "Geyman-Emily-C", "name": { "family": "Geyman", "given": "Emily C." }, "orcid": "0000-0003-4349-9350" }, { "id": "Reahl-Jocelyn-N", "name": { "family": "Reahl", "given": "Jocelyn N." }, "orcid": "0000-0001-5544-2138" }, { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Seelen-Emily-A", "name": { "family": "Seelen", "given": "Emily A." }, "orcid": "0000-0003-3782-9341" }, { "id": "Magyar-John-S", "name": { "family": "Magyar", "given": "John S." }, "orcid": "0000-0002-3586-8286" }, { "id": "Dunne-Kieran-B-J", "name": { "family": "Dunne", "given": "Kieran B. J." }, "orcid": "0000-0003-0995-7629" }, { "id": "Mutter-Edda", "name": { "family": "Mutter", "given": "Edda" }, "orcid": "0000-0002-1681-8080" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" }, { "id": "West-A-Joshua", "name": { "family": "West", "given": "A. Joshua" }, "orcid": "0000-0001-6909-1471" } ] }, "title": "Mercury stocks in discontinuous permafrost and their mobilization by river migration in the Yukon River Basin", "ispublished": "pub", "full_text_status": "public", "keywords": "Mercury; Arctic; permafrost; erosion; Rivers", "note": "

© 2024 The Author(s). Published by IOP Publishing Ltd.

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Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

\n\n
\n

This work was supported by the National Science Foundation (Grant Numbers: #2127442, #2127444, and #2127445), the Geological Society of America, and the Resnick Sustainability Institute at Caltech. We thank the Beaver Village Council and the Huslia Tribal Council for their invaluable support and the opportunity to work on their lands. We also thank our boat drivers and bear guards for guiding us: Alvin Attla, Darin Dayton, Shawn Huffman, Kody Vanderpool, Richard Williams, and Clinton Wiehl. Finally, we thank Rain Blankenship for processing sediment samples and Justin Nghiem and Hannah Dion-Kirschner for assistance in the field.

\n
\n\n

The data that support the findings of this study are openly available at the following URL/DOI: 10.18739/A2FX74076.

", "abstract": "
\n
\n

Rapid warming in the Arctic threatens to destabilize mercury (Hg) deposits contained within soils in permafrost regions. Yet current estimates of the amount of Hg in permafrost vary by ∼4 times. Moreover, how Hg will be released to the environment as permafrost thaws remains poorly known, despite threats to water quality, human health, and the environment. Here we present new measurements of total mercury (THg) contents in discontinuous permafrost in the Yukon River Basin in Alaska. We collected riverbank and floodplain sediments from exposed banks and bars near the villages of Huslia and Beaver. Median THg contents were 49+13/−21 ng THg g sediment−1 and 39+16/−18 ng THg g sediment−1 for Huslia and Beaver, respectively (uncertainties as 15th and 85th percentiles). Corresponding THg:organic carbon ratios were 5.4+2.0/−2.4 Gg THg Pg C−1 and 4.2 +2.4/−2.9 Gg THg Pg C−1. To constrain floodplain THg stocks, we combined measured THg contents with floodplain stratigraphy. Trends of THg increasing with smaller sediment size and calculated stocks in the upper 1 m and 3 m are similar to those suggested for this region by prior pan-Arctic studies. We combined THg stocks and river migration rates derived from remote sensing to estimate particulate THg erosional and depositional fluxes as river channels migrate across the floodplain. Results show similar fluxes within uncertainty into the river from erosion at both sites (95+12/−47 kg THg yr−1 and 26+154/−13 kg THg yr−1 at Huslia and Beaver, respectively), but different fluxes out of the river via deposition in aggrading bars (60+40/−29 kg THg yr−1 and 10+5.3/−1.7 kg THg yr−1). Thus, a significant amount of THg is liberated from permafrost during bank erosion, while a variable but generally lesser portion is subsequently redeposited by migrating rivers.

\n
\n
", "date": "2024-08", "date_type": "published", "publication": "Environmental Research Letters", "volume": "19", "number": "8", "publisher": "IOP Publishing", "pagerange": "084041", "issn": "1748-9326", "official_url": "https://authors.library.caltech.edu/records/nzaqm-dsz57", "funders": { "items": [ { "grant_number": "RISE-2127442" }, { "grant_number": "RISE-2127444" }, { "grant_number": "RISE-2127445" }, {}, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.7907/nzaqm-dsz57", "primary_object": { "basename": "Smith_2024_Environ._Res._Lett._19_084041.pdf", "url": "https://authors.library.caltech.edu/records/nzaqm-dsz57/files/Smith_2024_Environ._Res._Lett._19_084041.pdf" }, "pub_year": "2024", "author_list": "Smith, Magdalene I.; Ke, Yutian; et al." }, { "id": "https://authors.library.caltech.edu/records/h5z2c-86g12", "eprint_status": "archive", "datestamp": "2025-01-10 23:34:55", "lastmod": "2025-06-30 19:54:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xuan-Jerry-W", "name": { "family": "Xuan", "given": "Jerry W." }, "orcid": "0000-0002-6618-1137" }, { "name": { "family": "Hsu", "given": "Chih-Chun" }, "orcid": "0000-0002-5370-7494" }, { "name": { "family": "Finnerty", "given": "Luke" }, "orcid": "0000-0002-1392-0768" }, { "id": "Wang-Jason-J", "name": { "family": "Wang", "given": "Jason" }, "orcid": "0000-0003-0774-6502" }, { "id": "Ruffio-J-B", "name": { "family": "Ruffio", "given": "Jean-Baptiste" }, "orcid": "0000-0003-2233-4821" }, { "id": "Zhang-Yapeng", "name": { "family": "Zhang", "given": "Yapeng" }, "orcid": "0000-0003-0097-4414" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather" }, "orcid": "0000-0002-5375-4725" }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "id": "Mamajek-Eric-E", "name": { "family": "Mamajek", "given": "Eric E." }, "orcid": "0000-0003-2008-1488" }, { "id": "Inglis-Julie", "name": { "family": "Inglis", "given": "Julie" }, "orcid": "0000-0001-9164-7966" }, { "id": "Wallack-N-L", "name": { "family": "Wallack", "given": "Nicole L." }, "orcid": "0000-0003-0354-0187" }, { "name": { "family": "Bryan", "given": "Marta L." }, "orcid": "0000-0002-6076-5967" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "name": { "family": "Molli\u00e8re", "given": "Paul" }, "orcid": "0000-0003-4096-7067" }, { "name": { "family": "Hejazi", "given": "Neda" }, "orcid": "0000-0001-5541-6087" }, { "id": "Baker-Ashley", "name": { "family": "Baker", "given": "Ashley" }, "orcid": "0000-0002-6525-7013" }, { "id": "Bartos-Randall", "name": { "family": "Bartos", "given": "Randall" } }, { "name": { "family": "Calvin", "given": "Benjamin" }, "orcid": "0000-0003-4737-5486" }, { "name": { "family": "Cetre", "given": "Sylvain" } }, { "name": { "family": "Delorme", "given": "Jacques-Robert" }, "orcid": "0000-0001-8953-1008" }, { "name": { "family": "Doppmann", "given": "Greg" } }, { "id": "Echeverri-D", "name": { "family": "Echeverri", "given": "Daniel" }, "orcid": "0000-0002-1583-2040" }, { "name": { "family": "Fitzgerald", "given": "Michael P." }, "orcid": "0000-0002-0176-8973" }, { "id": "Jovanovic-N", "name": { "family": "Jovanovic", "given": "Nemanja" }, "orcid": "0000-0001-5213-6207" }, { "id": "Liberman-Joshua", "name": { "family": "Liberman", "given": "Joshua" }, "orcid": "0000-0002-4934-3042" }, { "name": { "family": "L\u00f3pez", "given": "Ronald A." }, "orcid": "0000-0002-2019-4995" }, { "name": { "family": "Morris", "given": "Evan" }, "orcid": "0000-0003-3165-0922" }, { "id": "Pezzato-Jacklyn", "name": { "family": "Pezzato", "given": "Jacklyn" } }, { "name": { "family": "Sappey", "given": "Ben" }, "orcid": "0000-0003-1399-3593" }, { "id": "Schofield-Tobias", "name": { "family": "Schofield", "given": "Tobias" } }, { "name": { "family": "Skemer", "given": "Andrew" }, "orcid": "0000-0001-6098-3924" }, { "id": "Wallace-J-Kent", "name": { "family": "Wallace", "given": "J. Kent" }, "orcid": "0000-0001-5299-6899" }, { "name": { "family": "Wang", "given": "Ji" }, "orcid": "0000-0002-4361-8885" }, { "name": { "family": "Agrawal", "given": "Shubh" }, "orcid": "0000-0003-2429-5811" }, { "id": "Horstman-Katelyn", "name": { "family": "Horstman", "given": "Katelyn" }, "orcid": "0000-0001-9708-8667" } ] }, "title": "Are These Planets or Brown Dwarfs? Broadly Solar Compositions from High-resolution Atmospheric Retrievals of \u223c10\u201330 M_(Jup) Companions", "ispublished": "pub", "full_text_status": "public", "keywords": "Exoplanet atmospheres; Brown dwarfs; High resolution spectroscopy; Exoplanet atmospheric composition; Atmospheric clouds; Exoplanet formation; Substellar companion stars", "note": "

© 2024. The Author(s). Published by the American Astronomical Society.

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Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

\n\n

J.X. thanks Melanie Rowland, Yayaati Chachan, Michael Liu, Kazumasa Ohno, Douglas Lin, Ricardo López-Valdivia, Henrique Reggiani, and Jingwen Zhang for helpful discussions. J.X. is supported by the NASA Future Investigators in NASA Earth and Space Science and Technology (FINESST) award No. 80NSSC23K1434. J.X. also acknowledges support from the Keck Visiting Scholars Program (KVSP) to commission KPIC Phase II capabilities. D.E. is supported by NASA FINESST award No. 80NSSC19K1423. D.E. also acknowledges support from the Keck Visiting Scholars Program (KVSP) to install the Phase II upgrades. Funding for KPIC has been provided by the California Institute of Technology, the Jet Propulsion Laboratory, the Heising-Simons Foundation (grant Nos. 2015-129, 2017-318, 2019-1312, 2023-4598), the Simons Foundation, and the NSF under grant AST-1611623. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. W. M. Keck Observatory access was supported by Northwestern University and the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA). The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This work benefited from the 2023 Exoplanet Summer Program in the Other Worlds Laboratory (OWL) at the University of California, Santa Cruz, a program funded by the Heising-Simons Foundation and NASA. The research here acknowledges use of the Hypatia Catalog Database, an online compilation of stellar abundance data as described in Hinkel et al. (2014), which was supported by NASA's Nexus for Exoplanet System Science (NExSS) research coordination network and the Vanderbilt Initiative in Data-Intensive Astrophysics (VIDA).

\n\n

Keck:II (KPIC) - KECK II Telescope.

\n\n

petitRADTRANS (Mollière et al. 2019), dynesty (Speagle 2020).

", "abstract": "

Using Keck Planet Imager and Characterizer high-resolution (R ∼ 35,000) spectroscopy from 2.29 to 2.49 μm, we present uniform atmospheric retrievals for eight young substellar companions with masses of ∼10–30 MJup, orbital separations spanning ∼50–360 au, and Teff between ∼1500 and 2600 K. We find that all companions have solar C/O ratios and metallicities to within the 1σ–2σ level, with the measurements clustered around solar composition. Stars in the same stellar associations as our systems have near-solar abundances, so these results indicate that this population of companions is consistent with formation via direct gravitational collapse. Alternatively, core accretion outside the CO snowline would be compatible with our measurements, though the high mass ratios of most systems would require rapid core assembly and gas accretion in massive disks. On a population level, our findings can be contrasted with abundance measurements for directly imaged planets with m < 10 MJup, which show tentative atmospheric metal enrichment compared to their host stars. In addition, the atmospheric compositions of our sample of companions are distinct from those of hot Jupiters, which most likely form via core accretion. For two companions with Teff ∼ 1700–2000 K (κ And b and GSC 6214–210 b), our best-fit models prefer a nongray cloud model with >3σ significance. The cloudy models yield 2σ−3σ lower Teff for these companions, though the C/O and [C/H] still agree between cloudy and clear models at the 1σ level. Finally, we constrain 12CO/13CO for three companions with the highest signal-to-noise ratio data (GQ Lup b, HIP 79098b, and DH Tau b) and report 

", "date": "2024-07-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "970", "number": "1", "publisher": "American Astronomical Society", "pagerange": "71", "issn": "0004-637X", "official_url": "https://authors.library.caltech.edu/records/h5z2c-86g12", "funders": { "items": [ { "grant_number": "80NSSC23K1434" }, { "grant_number": "Keck Visiting Scholars Program" }, { "grant_number": "80NSSC19K1423" }, {}, { "grant_number": "2015-129" }, { "grant_number": "2017-318" }, { "grant_number": "2019-1312" }, { "grant_number": "2023-4598" }, {}, { "grant_number": "AST-1611623" }, {}, {}, {} ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/1538-4357/ad4796", "primary_object": { "basename": "Xuan_2024_ApJ_970_71.pdf", "url": "https://authors.library.caltech.edu/records/h5z2c-86g12/files/Xuan_2024_ApJ_970_71.pdf" }, "pub_year": "2024", "author_list": "Xuan, Jerry W.; Hsu, Chih-Chun; et al." }, { "id": "https://authors.library.caltech.edu/records/7zhx0-mvp60", "eprint_status": "archive", "datestamp": "2024-06-13 19:38:04", "lastmod": "2025-11-10 19:51:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Silich-Emily-M", "name": { "family": "Silich", "given": "Emily M." }, "orcid": "0000-0002-1616-5649" }, { "id": "Bellomi-Elena", "name": { "family": "Bellomi", "given": "Elena" }, "orcid": "0000-0001-6411-3686" }, { "id": "Sayers-J", "name": { "family": "Sayers", "given": "Jack" }, "orcid": "0000-0002-8213-3784" }, { "id": "ZuHone-John", "name": { "family": "ZuHone", "given": "John" }, "orcid": "0000-0003-3175-2347" }, { "id": "Chadayammuri-Urmila", "name": { "family": "Chadayammuri", "given": "Urmila" }, "orcid": "0000-0003-2521-506X" }, { "id": "Golwala-S-R", "name": { "family": "Golwala", "given": "Sunil" }, "orcid": "0000-0002-1098-7174" }, { "id": "Hughes-David", "name": { "family": "Hughes", "given": "David" } }, { "id": "Monta\u00f1a-Alfredo", "name": { "family": "Monta\u00f1a", "given": "Alfredo" }, "orcid": "0000-0003-4229-381X" }, { "id": "Mroczkowski-Tony", "name": { "family": "Mroczkowski", "given": "Tony" }, "orcid": "0000-0003-3816-5372" }, { "id": "Nagai-Daisuke", "name": { "family": "Nagai", "given": "Daisuke" }, "orcid": "0000-0002-6766-5942" }, { "id": "S\u00e1nchez-Arg\u00fcelles-David", "name": { "family": "S\u00e1nchez-Arg\u00fcelles", "given": "David" }, "orcid": "0000-0002-7344-9920" }, { "id": "Stanford-Spencer-A", "name": { "family": "Stanford", "given": "S. A." }, "orcid": "0000-0003-0122-0841" }, { "id": "Wilson-Grant", "name": { "family": "Wilson", "given": "Grant" }, "orcid": "0000-0003-2705-9152" }, { "id": "Zemcov-Michael", "name": { "family": "Zemcov", "given": "Michael" }, "orcid": "0000-0001-8253-1451" }, { "id": "Zitrin-Adi", "name": { "family": "Zitrin", "given": "Adi" }, "orcid": "0000-0002-0350-4488" } ] }, "title": "ICM-SHOX. I. Methodology Overview and Discovery of a Gas\u2013Dark Matter Velocity Decoupling in the MACS J0018.5+1626 Merger", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

\n\n

Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology (Caltech), the University of California, and the National Aeronautics and Space Administration (NASA). The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

\n

The X-ray observations in this analysis were obtained from the Chandra Data Archive. The hydrodynamical simulations were run on the Pleiades supercomputer at NASA/Ames Research Center. The simulation post-processing computations were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at Caltech.

\n

E.M.S. acknowledges support from a National Science Foundation Graduate Research Fellowship (NSF GRFP) under grant No. DGE-1745301, the Wallace L. W. Sargent Graduate Fellowship at Caltech, and NSF/AST-2206082. J.S. acknowledges support from NSF/AST-2206082. J.A.Z. and U.C. are funded by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of NASA under contract NAS8-03060. E.B. acknowledges support from NSF/AST-2206083. A.Z. acknowledges support by grant No. 2020750 from the United States-Israel Binational Science Foundation (BSF) and grant No. 2109066 from the United States NSF, and by the Ministry of Science & Technology, Israel. T.M. acknowledges support from the AtLAST project, which has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 951815. A.M. thanks support from Consejo Nacional de Humanidades Ciencias y Technologías (CONAHCYT) project A1-S-45680. We thank the anonymous reviewer for the detailed comments, which helped improve this manuscript.

\n\n

Keck/DEIMOS - , CXO - Chandra X-ray Observatory satellite, CSO - Caltech Submillimeter Observatory, (installed on the 10 m Atacama Submillimeter Telescope Experiment) - Atacama Submillimeter Telescope Experiment, Planck - European Space Agency's Planck space observatory, HST - Hubble Space Telescope satellite

\n\n

GAMER-2 (Schive et al. 2018), Xspec 12.12.0 (Arnaud 1996), yt (Turk et al. 2011), pyXSIM (ZuHone & Hallman 2016), SOXS (ZuHone et al. 2023), mpi4py (Dalcin & Fang 2021), CIAO (Fruscione et al. 2006), PypeIt (Prochaska et al. 2020), spec2d (Cooper et al. 2012; Newman et al. 2013), SpecPro (Masters & Capak 2011), Pumpkin (Rhea et al. 2020), Astropy (Astropy Collaboration et al. 2013, 2018), NumPy (van der Walt et al. 2011; Harris et al. 2020), Matplotlib (Hunter 2007), lmfit (Newville et al. 2014), Colossus (Diemer 2018), contbin (Sanders 2006), scikit-image; (van der Walt et al. 2014)

", "abstract": "
\n

Galaxy cluster mergers are rich sources of information to test cluster astrophysics and cosmology. However, cluster mergers produce complex projected signals that are difficult to interpret physically from individual observational probes. Multi-probe constraints on the gas and dark matter (DM) cluster components are necessary to infer merger parameters that are otherwise degenerate. We present Improved Constraints on Mergers with SZ, Hydrodynamical simulations, Optical, and X-ray (ICM-SHOX), a systematic framework to jointly infer multiple merger parameters quantitatively via a pipeline that directly compares a novel combination of multi-probe observables to mock observables derived from hydrodynamical simulations. We report a first application of the ICM-SHOX pipeline to MACS J0018.5+1626, wherein we systematically examine simulated snapshots characterized by a wide range of initial parameters to constrain the MACS J0018.5+1626 merger geometry. We constrain the epoch of MACS J0018.5+1626 to the range 0–60 Myr post-pericenter passage, and the viewing angle is inclined ≈27°–40° from the merger axis. We obtain constraints for the impact parameter (\u2272250 kpc), mass ratio (≈1.5–3.0), and initial relative velocity when the clusters are separated by 3 Mpc (≈1700–3000 km s−1). The primary and secondary clusters initially (at 3 Mpc) have gas distributions that are moderately and strongly disturbed, respectively. We discover a velocity space decoupling of the DM and gas distributions in MACS J0018.5+1626, traced by cluster-member galaxy velocities and the kinematic Sunyaev–Zel'dovich effect, respectively. Our simulations indicate this decoupling is dependent on the different collisional properties of the two distributions for particular merger epochs, geometries, and viewing angles.

\n
", "date": "2024-06-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "968", "number": "2", "publisher": "American Astronomical Society", "pagerange": "74", "issn": "0004-637X", "official_url": "https://authors.library.caltech.edu/records/7zhx0-mvp60", "funders": { "items": [ {}, {}, { "grant_number": "DGE-1745301" }, { "grant_number": "Wallace L. W. Sargent Graduate Fellowship" }, { "grant_number": "AST-2206082" }, { "grant_number": "NAS8-03060" }, { "grant_number": "AST-2206083" }, { "grant_number": "2020750" }, { "grant_number": "AST-2109066" }, {}, { "grant_number": "951815" }, { "grant_number": "A1-S-45680" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/1538-4357/ad3fb5", "primary_object": { "basename": "Silich_2024_ApJ_968_74.pdf", "url": "https://authors.library.caltech.edu/records/7zhx0-mvp60/files/Silich_2024_ApJ_968_74.pdf" }, "pub_year": "2024", "author_list": "Silich, Emily M.; Bellomi, Elena; et al." }, { "id": "https://authors.library.caltech.edu/records/7bjnb-kck30", "eprint_status": "archive", "datestamp": "2024-06-11 21:19:31", "lastmod": "2024-06-11 21:19:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Yoonsoo", "name": { "family": "Kim", "given": "Yoonsoo" }, "orcid": "0000-0002-4305-6026" }, { "id": "Most-E-R", "name": { "family": "Most", "given": "Elias R." }, "orcid": "0000-0002-0491-1210" }, { "id": "Throwe-William", "name": { "family": "Throwe", "given": "William" }, "orcid": "0000-0001-5059-4378" }, { "id": "Teukolsky-S-A", "name": { "family": "Teukolsky", "given": "Saul A." }, "orcid": "0000-0001-9765-4526" }, { "id": "Deppe-Nils", "name": { "family": "Deppe", "given": "Nils" }, "orcid": "0000-0003-4557-4115" } ] }, "title": "General relativistic force-free electrodynamics with a discontinuous Galerkin-finite difference hybrid method", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 American Physical Society.

\n\n
\n
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The authors are grateful to Kyle Nelli and Nils Vu for helpful discussions and technical support during various stages of this project. Y. K. acknowledges Cristòbal Armaza for encouraging conversations. Computations were performed on the Wheeler cluster and Resnick HPC Center at Caltech. E. R. M. acknowledges support by the National Science Foundation under Grants No. AST-2307394 and No. PHY-2309210, the NSF Frontera supercomputer under grant AST21006, and Delta at the National Center for Supercomputing Applications (NCSA) through allocation No. PHY210074 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, which is supported by National Science Foundation Grants No. 2138259, No. 2138286, No. 2138307, No. 2137603, and No. 2138296. E. R. M. further acknowledges support on Perlmutter through NERSC under Grant No. m4575. The authors acknowledge partial support by the Sherman Fairchild Foundation, and by NSF Grants No. PHY-2207342 and No. OAC-2209655 at Cornell. Figures in this article were produced using matplotlib [115] and numpy [116] packages.

\n
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\n
", "abstract": "

Relativistic plasmas around compact objects can sometimes be approximated as being force-free. In this limit, the plasma inertia is negligible and the overall dynamics is governed by global electric currents. We present a novel numerical approach for simulating such force-free plasmas, which allows for high accuracy in smooth regions as well as capturing dissipation in current sheets. Using a high-order accurate discontinuous Galerkin method augmented with a conservative finite-difference method, we demonstrate efficient global simulations of black hole and neutron star magnetospheres. In addition to a series of challenging test problems, we show that our approach can—depending on the physical properties of the system and the numerical implementation—be up to 10× more efficient than conventional simulations, with a speedup of 2–3× for most problems we consider in practice.

", "date": "2024-06-15", "date_type": "published", "publication": "Physical Review D", "volume": "109", "number": "12", "publisher": "American Physical Society", "pagerange": "123019", "issn": "2470-0010", "official_url": "https://authors.library.caltech.edu/records/7bjnb-kck30", "funders": { "items": [ { "grant_number": "AST-2307394" }, { "grant_number": "PHY-2309210" }, { "grant_number": "AST21006" }, { "grant_number": "PHY210074" }, { "grant_number": "OAC-2138259" }, { "grant_number": "OAC-2138286" }, { "grant_number": "OAC-2138307" }, { "grant_number": "OAC-2137603" }, { "grant_number": "OAC-2138296" }, { "grant_number": "m4575" }, { "grant_number": "PHY-2207342" }, { "grant_number": "OAC-2209655" } ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "TAPIR" }, { "id": "Astronomy-Department" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevd.109.123019", "primary_object": { "basename": "PhysRevD.109.123019.pdf", "url": "https://authors.library.caltech.edu/records/7bjnb-kck30/files/PhysRevD.109.123019.pdf" }, "pub_year": "2024", "author_list": "Kim, Yoonsoo; Most, Elias R.; et al." }, { "id": "https://authors.library.caltech.edu/records/cgf0e-jx555", "eprint_status": "archive", "datestamp": "2024-06-12 16:17:57", "lastmod": "2025-11-19 00:29:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ma-Sizheng", "name": { "family": "Ma", "given": "Sizheng" }, "orcid": "0000-0002-4645-453X" }, { "id": "Moxon-Jordan", "name": { "family": "Moxon", "given": "Jordan" }, "orcid": "0000-0001-9891-8677" }, { "id": "Scheel-M-A", "name": { "family": "Scheel", "given": "Mark A." }, "orcid": "0000-0001-6656-9134" }, { "id": "Nelli-Kyle-C", "name": { "family": "Nelli", "given": "Kyle C." }, "orcid": "0000-0003-2426-8768" }, { "id": "Deppe-Nils", "name": { "family": "Deppe", "given": "Nils" }, "orcid": "0000-0003-4557-4115" }, { "id": "Bonilla-Marceline-S", "name": { "family": "Bonilla", "given": "Marceline S." }, "orcid": "0000-0003-4502-528X" }, { "id": "Kidder-Lawrence-E", "name": { "family": "Kidder", "given": "Lawrence E." }, "orcid": "0000-0001-5392-7342" }, { "id": "Kumar-Prayush", "name": { "family": "Kumar", "given": "Prayush" }, "orcid": "0000-0001-5523-4603" }, { "id": "Lovelace-Geoffrey", "name": { "family": "Lovelace", "given": "Geoffrey" }, "orcid": "0000-0002-7084-1070" }, { "id": "Throwe-William", "name": { "family": "Throwe", "given": "William" }, "orcid": "0000-0001-5059-4378" }, { "id": "Vu-Nils-L", "name": { "family": "Vu", "given": "Nils L." }, "orcid": "0000-0002-5767-3949" } ] }, "title": "Fully relativistic three-dimensional Cauchy-characteristic matching for physical degrees of freedom", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 American Physical Society.

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We thank Keefe Mitman and Justin Ripley for useful discussions. This work was supported in part by the Sherman Fairchild Foundation and by NSF Grants No. PHY-2011961, No. PHY-2011968, No. PHY2309231, and No. OAC-2209655 at Caltech. The computations presented here were conducted using the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. M. S. B. and G. L. acknowledge support from NSF awards No. PHY-1654359 and No. PHY-2208014, the Dan Black Family Trust, and Nicholas and Lee Begovich.

", "abstract": "

A fully relativistic three-dimensional Cauchy-characteristic matching (CCM) algorithm is implemented for physical degrees of freedom in a numerical relativity code spectre. The method is free of approximations and can be applied to any physical system. We test the algorithm with various scenarios involving smooth data, including the propagation of Teukolsky waves within a flat background, the perturbation of a Kerr black hole with a Teukolsky wave, and the injection of a gravitational-wave pulse from the characteristic grid. Our investigations reveal no numerical instabilities in the simulations. In addition, the tests indicate that the CCM algorithm effectively directs characteristic information into the inner Cauchy system, yielding higher precision in waveforms and smaller violations of Bondi-gauge constraints, especially when the outer boundary of the Cauchy evolution is at a smaller radius.

", "date": "2024-06-15", "date_type": "published", "publication": "Physical Review D", "volume": "109", "number": "12", "publisher": "American Physical Society", "pagerange": "124027", "issn": "2470-0010", "official_url": "https://authors.library.caltech.edu/records/cgf0e-jx555", "funders": { "items": [ {}, { "grant_number": "PHY-2011961" }, { "grant_number": "PHY-2011968" }, { "grant_number": "PHY-2309231" }, { "grant_number": "OAC-2209655" }, {}, { "grant_number": "PHY-1654359" }, { "grant_number": "PHY-2208014" }, { "agency": "Dan Black Family Trust" } ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "TAPIR" } ] }, "doi": "10.1103/physrevd.109.124027", "primary_object": { "basename": "PhysRevD.109.124027.pdf", "url": "https://authors.library.caltech.edu/records/cgf0e-jx555/files/PhysRevD.109.124027.pdf" }, "pub_year": "2024", "author_list": "Ma, Sizheng; Moxon, Jordan; et al." }, { "id": "https://authors.library.caltech.edu/records/pz2ep-dyv38", "eprint_status": "archive", "datestamp": "2024-06-13 16:27:51", "lastmod": "2024-06-13 16:27:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cagan-David-A", "name": { "family": "Cagan", "given": "David A." }, "orcid": "0000-0002-4719-2789" }, { "id": "B\u00edm-Daniel", "name": { "family": "B\u00edm", "given": "Daniel" }, "orcid": "0000-0003-3100-4293" }, { "id": "Kazmierczak-Nathanael-P", "name": { "family": "Kazmierczak", "given": "Nathanael P." }, "orcid": "0000-0002-7822-6769" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Mechanisms of Photoredox Catalysis Featuring Nickel\u2013Bipyridine Complexes", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

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\n

D.A.C. is a National Science Foundation Graduate Research Fellow (DGE-1745301) and is supported by a National Academies of Science, Engineering, and Medicine Ford Foundation Predoctoral Fellowship. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 883987 (D.B.). N.P.K. acknowledges support from the Hertz Fellowship and from the National Science Foundation Graduate Research Fellowship under Grant No. DGE1745301. Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R35-GM142595) (R.G.H.). The illustrative computations presented were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.

\n
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The authors declare no competing financial interest.

", "abstract": "
\n

Metallaphotoredox catalysis can unlock useful pathways for transforming organic reactants into desirable products, largely due to the conversion of photon energy into chemical potential to drive redox and bond transformation processes. Despite the importance of these processes for cross-coupling reactions and other transformations, their mechanistic details are only superficially understood. In this review, we have provided a detailed summary of various photoredox mechanisms that have been proposed to date for Ni–bipyridine (bpy) complexes, focusing separately on photosensitized and direct excitation reaction processes. By highlighting multiple bond transformation pathways and key findings, we depict how photoredox reaction mechanisms, which ultimately define substrate scope, are themselves defined by the ground- and excited-state geometric and electronic structures of key Ni-based intermediates. We further identify knowledge gaps to motivate future mechanistic studies and the development of synergistic research approaches spanning the physical, organic, and inorganic chemistry communities.

\n
", "date": "2024-06-07", "date_type": "published", "publication": "ACS Catalysis", "volume": "14", "number": "11", "publisher": "American Chemical Society", "pagerange": "905-9076", "issn": "2155-5435", "official_url": "https://authors.library.caltech.edu/records/pz2ep-dyv38", "funders": { "items": [ { "grant_number": "DGE-1745301" }, {}, {}, { "grant_number": "883987" }, {}, { "grant_number": "R35-GM142595" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "pmcid": "PMC11165457", "primary_object": { "basename": "cs4c02036.pdf", "url": "https://authors.library.caltech.edu/records/pz2ep-dyv38/files/cs4c02036.pdf" }, "pub_year": "2024", "author_list": "Cagan, David A.; B\u00edm, Daniel; et al." }, { "id": "https://authors.library.caltech.edu/records/g0z8x-2m475", "eprint_status": "archive", "datestamp": "2024-06-05 17:36:30", "lastmod": "2024-06-11 16:21:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Sutcliffe", "given": "Erica" } }, { "name": { "family": "Cagan", "given": "David A." }, "orcid": "0000-0002-4719-2789" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Ultrafast Photophysics of Ni(I)\u2013Bipyridine Halide Complexes: Spanning the Marcus Normal and Inverted Regimes", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

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D.A.C. acknowledges support from the National Science Foundation Graduate Research Fellowship (NSF GRFP) under grant no. DGE-1745301. The Caltech EPR facility acknowledges support from the Beckman Institute and the Dow Next Generation Educator Fund. Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R35-GM142595). The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. We thank M. Shahgholi for their assistance in collection of mass spectrometry data and M. Takase for collection and solving of the crystal structure; instrumentation for both mass spectrometry and X-ray crystallography were enabled by funds from the Caltech DOW Next Generation Instrumentation Fund.

\n
\n\n

E.S. and D.A.C. contributed equally.

\n\n\n\n

The authors declare no competing financial interest.

", "abstract": "
\n

Owing to their light-harvesting properties, nickel–bipyridine (bpy) complexes have found wide use in metallaphotoredox cross-coupling reactions. Key to these transformations are Ni(I)–bpy halide intermediates that absorb a significant fraction of light at relevant cross-coupling reaction irradiation wavelengths. Herein, we report ultrafast transient absorption (TA) spectroscopy on a library of eight Ni(I)–bpy halide complexes, the first such characterization of any Ni(I) species. The TA data reveal the formation and decay of Ni(I)-to-bpy metal-to-ligand charge transfer (MLCT) excited states (10–30 ps) whose relaxation dynamics are well described by vibronic Marcus theory, spanning the normal and inverted regions as a result of simple changes to the bpy substituents. While these lifetimes are relatively long for MLCT excited states in first-row transition metal complexes, their duration precludes excited-state bimolecular reactivity in photoredox reactions. We also present a one-step method to generate an isolable, solid-state Ni(I)–bpy halide species, which decouples light-initiated reactivity from dark, thermal cycles in catalysis.

\n
", "date": "2024-06-05", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "146", "number": "22", "publisher": "American Chemical Society", "pagerange": "15506-15514", "issn": "0002-7863", "official_url": "https://authors.library.caltech.edu/records/g0z8x-2m475", "funders": { "items": [ { "grant_number": "DGE-1745301" }, { "grant_number": "Beckman Institute" }, { "grant_number": "Dow Next Generation Educator Fund" }, { "grant_number": "R35-GM142595" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.4c04091", "pmcid": "PMC11157544", "primary_object": { "basename": "sutcliffe-et-al-2024-ultrafast-photophysics-of-ni(i)-bipyridine-halide-complexes-spanning-the-marcus-normal-and.pdf", "url": "https://authors.library.caltech.edu/records/g0z8x-2m475/files/sutcliffe-et-al-2024-ultrafast-photophysics-of-ni(i)-bipyridine-halide-complexes-spanning-the-marcus-normal-and.pdf" }, "related_objects": [ { "basename": "ja4c04091_si_001.pdf", "url": "https://authors.library.caltech.edu/records/g0z8x-2m475/files/ja4c04091_si_001.pdf" } ], "pub_year": "2024", "author_list": "Sutcliffe, Erica; Cagan, David A.; et al." }, { "id": "https://authors.library.caltech.edu/records/jpkh4-2xz90", "eprint_status": "archive", "datestamp": "2024-05-30 22:59:13", "lastmod": "2024-05-30 23:01:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Karimi-Mina", "name": { "family": "Karimi", "given": "Mina" }, "orcid": "0000-0003-3863-6015" }, { "id": "Bhattacharya-K", "name": { "family": "Bhattacharya", "given": "Kaushik" }, "orcid": "0000-0003-2908-5469" } ] }, "title": "Accelerated computational micromechanics for solute transport in porous media", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 Elsevier.

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We gratefully acknowledge the financial support of the Resnick Sustainability Institute at the California Institute of Technology. KB also acknowledges the support of the Army Research Office, United States through grant number W911NF-22-1-0269. The simulations reported here were conducted on the Resnick High Performance Computing Cluster at the California Institute of Technology.

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Mina Karimi: Writing – review & editing, Writing – original draft, Visualization, Validation, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Kaushik Bhattacharya: Writing – review & editing, Writing – original draft, Visualization, Supervision, Resources, Project administration, Methodology, Investigation, Funding acquisition, Formal analysis, Conceptualization.

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Data will be made available on request.

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MMC S1. Accelerated Computational Micromechanics for Solute Transport in Porous Media
\n\n

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

", "abstract": "
\n
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\n

Reactive transport in permeable porous media is relevant for a variety of applications, but poses a significant challenge due to the range of length and time scales. Multiscale methods that aim to link microstructure with the macroscopic response of geo-materials have been developed, but require the repeated solution of the small-scale problem and provide the motivation for this work. We present an efficient computational method to study fluid flow and solute transport problems in periodic porous media. Fluid flow is governed by the Stokes equation, and the solute transport is governed by the advection–diffusion equation. We follow the accelerated computational micromechanics approach that leads to an iterative computational method where each step is either local or the solution of a Poisson’s equation. This enables us to implement these methods on accelerators like graphics processing units (GPUs) and exploit their massively parallel architecture. We verify the approach by comparing the results against established computational methods and then demonstrate the accuracy, efficacy, and performance by studying various examples. This method efficiently calculates the effective transport properties for complex pore geometries.

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\n
\n
\n", "date": "2024-06-01", "date_type": "published", "publication": "Computer Methods in Applied Mechanics and Engineering", "volume": "426", "publisher": "Elsevier", "pagerange": "116976", "issn": "0045-7825", "official_url": "https://authors.library.caltech.edu/records/jpkh4-2xz90", "funders": { "items": [ {}, { "grant_number": "W911NF-22-1-0269" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.cma.2024.116976", "primary_object": { "basename": "1-s2.0-S0045782524002329-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/jpkh4-2xz90/files/1-s2.0-S0045782524002329-mmc1.pdf" }, "pub_year": "2024", "author_list": "Karimi, Mina and Bhattacharya, Kaushik" }, { "id": "https://authors.library.caltech.edu/records/bmj14-tyb04", "eprint_status": "archive", "datestamp": "2024-06-26 20:21:21", "lastmod": "2024-06-26 20:21:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "name": { "family": "Lai", "given": "Yungchieh" } }, { "name": { "family": "Guevarra", "given": "Dan" } }, { "name": { "family": "Kan", "given": "Kevin" } }, { "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Accelerated screening of gas diffusion electrodes for carbon dioxide reduction", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.

\n\n

This material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. The Resnick Sustainability Institute at Caltech is acknowledged for its support of enabling infrastructure and facilities. The authors thank Aidan Fenwick, Gavin Heim, and Theodor Agapie for helpful discussion, and Aidan Fenwick for deposition of the Cu on the GDE.

\n\n

R. J. J. and J. M. G. designed AutoGDE with input from all co-authors. R. J. J. and Y. L. assembled AutoGDE. D. G., K. K., and Y. L. developed the instrument control software. Y. L. procured and analyzed the demonstration data. J. M. G. was the primary author of the manuscript with contributions from all authors. R. J. R and Y. L. were the primary authors of the assembly and operation instructions. J. A. H. and J. M. G. supervised the project.

\n\n

The instrument control software is available at https://github.com/High-Throughput-Experimentation/helao-async, with dependencies in https://github.com/High-Throughput-Experimentation/helao-core. These repositories contain the MIT License. The hardware design for AutoGDE is comprised of drawings and machining instructions, assembly instructions, pseudo-code for instrument operation, python code for the HELAO sequence for collection of demonstration data, data files acquired for the present work, and the source code for the analysis and plotting of those data, which are provided under the CERN Open Hardware License, CERN-OHL-P, via CaltechData at https://data.caltech.edu/records/f40n8-cv274 (doi: https://doi.org/10.22002/f40n8-cv274).

\n\n

J. M. G. is an industrial consultant for experiment automation.

", "abstract": "
\n

The electrochemical conversion of carbon dioxide to chemicals and fuels is expected to be a key sustainability technology. Electrochemical carbon dioxide reduction technologies are challenged by several factors, including the limited solubility of carbon dioxide in aqueous electrolyte as well as the difficulty in utilizing polymer electrolytes. These considerations have driven system designs to incorporate gas diffusion electrodes (GDEs) to bring the electrocatalyst in contact with both a gaseous reactant/product stream as well as a liquid electrolyte. GDE optimization typically results from manual tuning by select experts. Automated preparation and operation of GDE cells could be a watershed for the systematic study of, and ultimately the development of a materials acceleration platform (MAP) for, catalyst discovery and system optimization. Toward this end, we present the automated GDE (AutoGDE) testing system. Given a catalyst-coated GDE, AutoGDE automates the insertion of the GDE into an electrochemical cell, the liquid and gas handling, the quantification of gaseous reaction products via online mass spectroscopy, and the archiving of the liquid electrolyte for subsequent analysis.

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", "date": "2024-06", "date_type": "published", "publication": "Digital Discovery", "volume": "3", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1144-1149", "issn": "2635-098X", "official_url": "https://authors.library.caltech.edu/records/bmj14-tyb04", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, {} ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/D4DD00061G", "primary_object": { "basename": "d4dd00061g1.pdf", "url": "https://authors.library.caltech.edu/records/bmj14-tyb04/files/d4dd00061g1.pdf" }, "related_objects": [ { "basename": "d4dd00061g.pdf", "url": "https://authors.library.caltech.edu/records/bmj14-tyb04/files/d4dd00061g.pdf" } ], "pub_year": "2024", "author_list": "Jones, Ryan J. R.; Lai, Yungchieh; et al." }, { "id": "https://authors.library.caltech.edu/records/rtyqz-vt064", "eprint_status": "archive", "datestamp": "2024-06-18 17:34:23", "lastmod": "2026-01-14 12:30:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oberhofer-Georg", "name": { "family": "Oberhofer", "given": "Georg" }, "orcid": "0000-0003-0930-1996" }, { "id": "Johnson-Michelle-L", "name": { "family": "Johnson", "given": "Michelle L." }, "orcid": "0000-0003-3646-8062" }, { "id": "Ivy-Tobin-W", "name": { "family": "Ivy", "given": "Tobin" }, "orcid": "0000-0002-9116-3854" }, { "id": "Antoshechkin-Igor-A", "name": { "family": "Antoshechkin", "given": "Igor" }, "orcid": "0000-0002-9934-3040" }, { "id": "Hay-B-A", "name": { "family": "Hay", "given": "Bruce A." }, "orcid": "0000-0002-5486-0482" } ] }, "title": "Cleave and Rescue gamete killers create conditions for gene drive in plants", "ispublished": "pub", "full_text_status": "public", "note": "

© The Author(s), under exclusive licence to Springer Nature Limited 2024.

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We thank E. Meyerowitz and members of the Meyerowitz Lab Paul Tarr and Carla de Agostini Verna for introducing us to techniques for Arabidopsis maintenance, transgenesis and crossing. This work was supported by a grant to B.A.H. from the Caltech Center for Evolutionary Science (G.O. and M.L.J.) and the Caltech Resnick Sustainability Institute Explorer Grant (G.O.). T.I. was supported by NIH Training grant number 5T32GM007616-39 and with support to B.A.H. from the US Department of Agriculture, National Institute of Food and Agriculture (NIFA) specialty crop initiative under US Department of Agriculture NIFA award number 2012-51181-20086.

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Conceptualization, G.O., T.I. and B.A.H.; methodology, G.O., T.I., M.L.J., I.A. and B.A.H.; investigation, G.O., M.L.J., I.A. and B.A.H.; writing—original draft, G.O. and B.A.H.; writing—review and editing, G.O., T.I., M.L.J., I.A. and B.A.H.; funding acquisition, B.A.H.

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All data are available in the main text and the Supplementary Information files. Illumina sequencing reads were deposited to SRA (bioproject, PRJNA1074841). The Arabidopsis TAIR 10 genome assembly was used in this study. Constructs and seeds of transgenic plants created in this study are available upon request.

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Extended Data Fig. 1 Alignment of the recoded A. lyrata rescue coding region to the A. thaliana target.

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Extended Data Fig. 2 T3 heterozygous ClvR crosses for (a) female ClvRap and (b) male ClvRap.

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Extended Data Fig. 3 T3 heterozygous ClvR crosses for (a) female ClvRCaMV35S and (b) male ClvRCaMV35S.

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Extended Data Fig. 4 Images of individual (a) and whole pots (b) of heterozygous ClvRubq, homozygous ClvRubq and WT plants.

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Modelling code and more information on the model, the scripts and parameters used to generate the data, and the data itself can be found at https://github.com/HayLab/Pigss. Plots were generated in R (version 4.2.3) with the ggplot2 package122.

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The authors have filed patent applications on ClvR and related technologies (US application numbers 15/970,728 and 16/673,823).

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", "abstract": "
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Gene drive elements promote the spread of linked traits and can be used to change the composition or fate of wild populations. Cleave and Rescue (ClvR) drive elements sit at a fixed chromosomal position and include a DNA sequence-modifying enzyme such as Cas9/gRNAs that disrupts endogenous versions of an essential gene and a recoded version of the essential gene resistant to cleavage. ClvR spreads by creating conditions in which those lacking ClvR die because they lack functional versions of the essential gene. Here we demonstrate the essential features of the ClvR gene drive in the plant Arabidopsis thaliana through killing of gametes that fail to inherit a ClvR that targets the essential gene YKT61. Resistant alleles, which can slow or prevent drive, were not observed. Modelling shows plant ClvRs are robust to certain failure modes and can be used to rapidly drive population modification or suppression. Possible applications are discussed.

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", "date": "2024-06", "date_type": "published", "publication": "Nature Plants", "volume": "10", "number": "6", "publisher": "Nature Publishing Group", "pagerange": "936-953", "issn": "2055-0278", "official_url": "https://authors.library.caltech.edu/records/rtyqz-vt064", "funders": { "items": [ { "grant_number": "Caltech Center for Evolutionary Science" }, {}, { "grant_number": "5T32GM007616-39" }, { "grant_number": "2012-51181-20086" } ] }, "local_group": { "items": [ { "id": "Division-of-Biology-and-Biological-Engineering" }, { "id": "Caltech-Center-for-Evolutionary-Science" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41477-024-01701-3", "primary_object": { "basename": "41477_2024_1701_Fig11_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig11_ESM.jpg" }, "related_objects": [ { "basename": "41477_2024_1701_Fig13_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig13_ESM.jpg" }, { "basename": "41477_2024_1701_Fig14_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig14_ESM.jpg" }, { "basename": "41477_2024_1701_Fig17_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig17_ESM.jpg" }, { "basename": "41477_2024_1701_Fig18_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig18_ESM.jpg" }, { "basename": "41477_2024_1701_Fig9_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig9_ESM.jpg" }, { "basename": "41477_2024_1701_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_MOESM1_ESM.pdf" }, { "basename": "41477_2024_1701_MOESM3_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_MOESM3_ESM.xlsx" }, { "basename": "41477_2024_1701_Fig10_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig10_ESM.jpg" }, { "basename": "41477_2024_1701_Fig12_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig12_ESM.jpg" }, { "basename": "41477_2024_1701_Fig15_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig15_ESM.jpg" }, { "basename": "41477_2024_1701_Fig16_ESM.jpg", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_Fig16_ESM.jpg" }, { "basename": "41477_2024_1701_MOESM4_ESM.zip", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_MOESM4_ESM.zip" }, { "basename": "41477_2024_1701_MOESM5_ESM.zip", "url": "https://authors.library.caltech.edu/records/rtyqz-vt064/files/41477_2024_1701_MOESM5_ESM.zip" } ], "pub_year": "2024", "author_list": "Oberhofer, Georg; Johnson, Michelle L.; et al." }, { "id": "https://authors.library.caltech.edu/records/g16t4-xhs17", "eprint_status": "archive", "datestamp": "2024-06-03 21:47:56", "lastmod": "2025-03-21 21:15:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Dion-Kirschner", "given": "Hannah" }, "orcid": "0000-0001-5978-5250" }, { "id": "Nguyen-Newton-H", "name": { "family": "Nguyen", "given": "Newton H." }, "orcid": "0000-0002-9118-8672" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward" }, "orcid": "0000-0002-8836-3054" } ] }, "title": "Evaluating the contribution of methanotrophy kinetics to uncertainty in the soil methane sink", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Author(s). Published by IOP Publishing. 

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Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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This project was supported by the Resnick Sustainability Institute at Caltech and the Center for Environmental-Microbial Interactions at Caltech. We express our gratitude to Benjamin Poulter, Xiaojing (Ruby) Fu, Adrian Moure, Avi Flamholz, Joshua Goldford, and Tapio Schneider for helpful discussions of early results, to Joshua Anadu for assistance with data visualization, to three anonymous reviewers for insightful suggestions for improving this work, and to Christopher Cappa and three reviewers for constructive feedback on an earlier version of the manuscript.

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All data that support the findings of this study are included within the article (and any supplementary files). The compiled dataset is additionally available on Zenodo at doi: 10.5281/zenodo.11225342.

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Focus on Methane Drawdown

", "abstract": "
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The oxidation of atmospheric methane by soil microbes is an important natural sink for a potent greenhouse gas. However, estimates of the current and future soil methane sink are highly uncertain. Here we assessed the extent to which methanotrophy enzyme kinetics contribute to uncertainty in projections of the soil methane sink. We generated a comprehensive compilation of methanotrophy kinetic data from modern environments and assessed the patterns in kinetic parameters present in natural samples. Our compiled data enabled us to quantify the global soil methane sink through two idealized calculations comparing first-order and Michaelis–Menten models of kinetics. We show that these two kinetic models diverge only under high atmospheric CH4 scenarios, where first-order rate constants slightly overestimate the soil methane sink size, but produce similar predictions at modern atmospheric concentrations. Our compilation also shows that the kinetics of methanotrophy in natural soil samples is highly variable—both the Vmax (oxidation rate at saturation) and KM (half-saturation constant) in natural samples span over six orders of magnitude. However, accounting for the correlation we observe between Vmax and KM reduces the range of calculated uptake rates by as much as 96%. Additionally, our results indicate that variation in enzyme kinetics introduces a similar magnitude of variation in the calculated soil methane sink as temperature sensitivity. Systematic sampling of methanotroph kinetic parameters at multiple spatial scales should therefore be a key objective for closing the budget on the global soil methane sink.

\n
", "date": "2024-06", "date_type": "published", "publication": "Environmental Research Letters", "volume": "19", "number": "6", "publisher": "IOP Publishing", "pagerange": "064059", "issn": "1748-9326", "official_url": "https://authors.library.caltech.edu/records/g16t4-xhs17", "funders": { "items": [ {}, { "agency": "Caltech Center for Environmental-Microbial Interactions" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Caltech-Center-for-Environmental-Microbial-Interactions-(CEMI)" } ] }, "doi": "10.1088/1748-9326/ad4c7a", "primary_object": { "basename": "Dion-Kirschner_2024_Environ._Res._Lett._19_064059.pdf", "url": "https://authors.library.caltech.edu/records/g16t4-xhs17/files/Dion-Kirschner_2024_Environ._Res._Lett._19_064059.pdf" }, "pub_year": "2024", "author_list": "Dion-Kirschner, Hannah; Nguyen, Newton H.; et al." }, { "id": "https://authors.library.caltech.edu/records/x1qf3-th671", "eprint_status": "archive", "datestamp": "2024-05-30 19:42:38", "lastmod": "2024-05-30 19:42:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dowling-Jacqueline-A", "name": { "family": "Dowling", "given": "Jacqueline A." }, "orcid": "0000-0001-5642-8960" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Swint-Madeleine-C", "name": { "family": "Swint", "given": "Madeleine C." } }, { "id": "Ye-Alexandre-Z", "name": { "family": "Ye", "given": "Alexandre Z." }, "orcid": "0009-0003-4895-0160" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Li-Anna-X", "name": { "family": "Li", "given": "Anna X." }, "orcid": "0000-0002-3435-3651" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Catalysis of the Oxygen-Evolution Reaction in 1.0 M Sulfuric Acid by Manganese Antimonate Films Synthesized via Chemical Vapor Deposition", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; Materials Chemistry; Electrochemistry; Energy Engineering and Power Technology; Chemical Engineering (miscellaneous)", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

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This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Science under Award Number DE-FG02-03-ER15483. ICP-MS data were collected at the Water and Environment Lab of the Resnick Sustainability Institute at the California Institute of Technology. XPS data were collected at the Molecular Materials Resource Center of the Beckman Institute at the California Institute of Technology.

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J.A.D. and Z.P.I. contributed equally.

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The authors declare the following competing financial interest(s): N.S.L. is a scientific founder of and consultant to H2U Technologies, a company developing catalysts and electrolyzers for the production of hydrogen.

", "abstract": "

Manganese antimonate (MnySb1–yOx) electrocatalysts for the oxygen-evolution reaction (OER) were synthesized via chemical vapor deposition. Mn-rich rutile Mn0.63Sb0.37Ox catalysts on fluorine-doped tin oxide (FTO) supports drove the OER for 168 h (7 days) at 10 mA cm–2 with a time-averaged overpotential of 687 ± 9 mV and with >97% Faradaic efficiency. Time-dependent anolyte composition analysis revealed the steady dissolution of Mn and Sb. Extended durability analysis confirmed that Mn-rich MnySb1–yOx materials are more active but dissolve at a faster rate than previously reported Sb-rich MnySb1–yOx alloys.

", "date": "2024-05-27", "date_type": "published", "publication": "ACS Applied Energy Materials", "volume": "7", "number": "10", "publisher": "American Chemical Society", "pagerange": "4288-4293", "issn": "2574-0962", "official_url": "https://authors.library.caltech.edu/records/x1qf3-th671", "funders": { "items": [ { "grant_number": "DE-FG02-03-ER15483" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsaem.4c00135", "pmcid": "PMC11134315", "primary_object": { "basename": "ae4c00135.pdf", "url": "https://authors.library.caltech.edu/records/x1qf3-th671/files/ae4c00135.pdf" }, "related_objects": [ { "basename": "ae4c00135_si_001.pdf", "url": "https://authors.library.caltech.edu/records/x1qf3-th671/files/ae4c00135_si_001.pdf" } ], "pub_year": "2024", "author_list": "Dowling, Jacqueline A.; Ifkovits, Zachary P.; et al." }, { "id": "https://authors.library.caltech.edu/records/z55y2-m8t18", "eprint_status": "archive", "datestamp": "2024-05-30 22:01:19", "lastmod": "2025-04-26 02:51:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Heim-Gavin-P", "name": { "family": "Heim", "given": "Gavin P." }, "orcid": "0000-0002-9244-6565" }, { "id": "Bruening-Meaghan-A", "name": { "family": "Bruening", "given": "Meaghan A." }, "orcid": "0000-0001-8132-9497" }, { "id": "Musgrave-Charles-B-III", "name": { "family": "Musgrave", "given": "Charles B., III" }, "orcid": "0000-0002-3432-0817" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Potassium ion modulation of the Cu electrode-electrolyte interface with ionomers enhances CO\u2082 reduction to C\u2082\u208a products", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 Elsevier.

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This material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award DE-SC0021266. The Resnick Sustainability Institute at Caltech is acknowledged for support of the laboratory facilities in which this research was conducted. This work also used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under contract no. DE-AC02-05CH11231 using NERSC award BES-ERCAP0024109. We are grateful to Dr. Yungchieh Lai for assistance with ICP-MS measurements.

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G.P.H. performed electrochemistry experiments. M.A.B. synthesized and characterized polymers. C.B.M. performed molecular dynamics simulations. T.A., J.C.P., and W.A.G. supervised the project. All authors analyzed data and prepared the manuscript.

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The data presented in this work are available from the corresponding authors upon reasonable request.

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Document S1. Supplemental experimental procedures, Figures S1–S22, Tables S1–S10, and supplemental references

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The authors declare no competing interests.

", "abstract": "
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Ionomers have shown promise as organic coatings on Cu electrodes to increase the CO2 reduction (CO2R) selectivity toward multi-carbon (C2+) products. However, the effects of systematic polymer structure modification on electrocatalytic performance have been seldom reported. Herein, we report on a series of polystyrene-based ionomers to probe the effect of local [K+] in the Cu electrode microenvironment on CO2R performance. Partial current density toward C2+ products (|jC2+|) increases with [K+] in ionomers, up to 225 mA cm−2. Replacing K+ with [Me4N]+ lowers performance to the level of bare Cu, highlighting the crucial role of K+ in improving C2+ product selectivity. Molecular dynamics simulations show that CO2 diffusivity increases with [K+], implicating CO2 transport to the electrode as a potential mechanism for improved CO2R performance. Our results highlight the intersection of synthetic polymer chemistry and electrocatalysis as a promising strategy in electrode modification toward achieving high selectivity of value-added chemicals.

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", "date": "2024-05-15", "date_type": "published", "publication": "Joule", "volume": "8", "number": "5", "publisher": "Cell Press", "pagerange": "1312-1321", "issn": "2542-4351", "official_url": "https://authors.library.caltech.edu/records/z55y2-m8t18", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, {}, { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "BES-ERCAP0024109" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.joule.2024.03.019", "primary_object": { "basename": "1-s2.0-S2542435124001545-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/z55y2-m8t18/files/1-s2.0-S2542435124001545-mmc1.pdf" }, "pub_year": "2024", "author_list": "Heim, Gavin P.; Bruening, Meaghan A.; et al." }, { "id": "https://authors.library.caltech.edu/records/5resg-98912", "eprint_status": "archive", "datestamp": "2025-04-07 22:34:59", "lastmod": "2025-04-07 22:36:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Noh-Brayden", "name": { "family": "Noh", "given": "Brayden" } }, { "id": "Wani-Omar", "name": { "family": "Wani", "given": "Omar" }, "orcid": "0000-0002-3124-3705" }, { "id": "Dunne-Kieran-B-J", "name": { "family": "Dunne", "given": "Kieran B. J." }, "orcid": "0000-0003-0995-7629" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Geomorphic risk maps for river migration using probabilistic modeling \u2013 a framework", "ispublished": "pub", "full_text_status": "public", "note": "

© Author(s) 2024. This work is distributed under the Creative Commons Attribution 4.0 License.

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Published by Copernicus Publications on behalf of the European Geosciences Union.

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Omar Wani thanks the Swiss National Science Foundation for support with its Early Postdoc Mobility Fellowship under grant number P2EZP2 195654. Michael P. Lamb acknowledges funding from the Resnick Sustainability Institute at Caltech under NSF awards 2127442 and 2031532.

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OW and MPL conceptualized the study. OW developed the methodology, wrote the initial code, and wrote the paper. BN, with guidance from OW, built on the initial code, conducted detailed simulation experiments, generated and analyzed the results, and plotted the figures. OW, KBJD, and MPL supervised BN. MPL supervised OW and KBJD. All authors contributed ideas and provided feedback during the research phase. KBJD and MPL also contributed insights on the geomorphic modeling of migrating rivers. All authors contributed to the review and editing of the paper during the writing phase.

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The code and data used in this study are provided at https://github.com/braydennoh/StochasticRiverMigration (Noh, 2024).

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At least one of the (co-)authors is a member of the editorial board of Earth Surface Dynamics. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare.

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This paper was edited by Sagy Cohen and reviewed by Keith Beven and one anonymous referee.

", "abstract": "

Lateral migration of meandering rivers poses erosional risks to human settlements, roads, and infrastructure in alluvial floodplains. While there is a large body of scientific literature on the dominant mechanisms driving river migration, it is still not possible to accurately predict river meander evolution over multiple years. This is in part because we do not fully understand the relative contribution of each mechanism and because deterministic mathematical models are not equipped to account for stochasticity in the system. Besides, uncertainty due to model structure deficits and unknown parameter values remains. For a more reliable assessment of risks, we therefore need probabilistic forecasts. Here, we present a workflow to generate geomorphic risk maps for river migration using probabilistic modeling. We start with a simple geometric model for river migration, where nominal migration rates increase with local and upstream curvature. We then account for model structure deficits using smooth random functions. Probabilistic forecasts for river channel position over time are generated by Monte Carlo runs using a distribution of model parameter values inferred from satellite data. We provide a recipe for parameter inference within the Bayesian framework. We demonstrate that such risk maps are relatively more informative in avoiding false negatives, which can be both detrimental and costly, in the context of assessing erosional hazards due to river migration. Our results show that with longer prediction time horizons, the spatial uncertainty of erosional hazard within the entire channel belt increases – with more geographical area falling within 25 % < probability < 75 %. However, forecasts also become more confident about erosion for regions immediately in the vicinity of the river, especially on its cut-bank side. Probabilistic modeling thus allows us to quantify our degree of confidence – which is spatially and temporally variable – in river migration forecasts. We also note that to increase the reliability of these risk maps, we need to describe the first-order dynamics in our model to a reasonable degree of accuracy, and simple geometric models do not always possess such accuracy.

", "date": "2024-05-08", "date_type": "published", "publication": "Earth Surface Dynamics", "volume": "12", "number": "3", "publisher": "European Geosciences Union", "pagerange": "691-708", "issn": "2196-632X", "official_url": "https://authors.library.caltech.edu/records/5resg-98912", "funders": { "items": [ { "grant_number": "P2EZP2 195654" }, {}, { "grant_number": "RISE-2127442" }, { "grant_number": "2031532" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.5194/esurf-12-691-2024", "primary_object": { "basename": "esurf-12-691-2024.pdf", "url": "https://authors.library.caltech.edu/records/5resg-98912/files/esurf-12-691-2024.pdf" }, "pub_year": "2024", "author_list": "Noh, Brayden; Wani, Omar; et al." }, { "id": "https://authors.library.caltech.edu/records/9s5yb-gxz04", "eprint_status": "archive", "datestamp": "2024-05-15 15:00:19", "lastmod": "2024-06-04 21:08:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "name": { "family": "Romero", "given": "Catherine G." } }, { "name": { "family": "Winkler", "given": "Jay R." }, "orcid": "0000-0002-4453-9716" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Intermolecular Proton-Coupled Electron Transfer Reactivity from a Persistent Charge-Transfer State for Reductive Photoelectrocatalysis", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

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\n

We thank the NIH (R01 GM-070757 (J.C.P.) and 1S10OD032151-01 (J.R.W.)) for support of this work. We also thank the Dow Next Generation Educator Funds and Instrumentation Grants for their support of the NMR facility at Caltech, and the Resnick Water and Environment Laboratory at Caltech for the use of their instrumentation. The authors are grateful to the American Chemical Society Petroleum Research Fund for support. We are thankful to Dr. David Vander Velde for technical NMR guidance and the laboratory of Professor Ryan Hadt for assistance with spectroelectrochemical studies. P.G.B. thanks the Ramón Areces Foundation for a postdoctoral fellowship. C.G.R. acknowledges the support of the NSF for a graduate fellowship (GRFP). J.C.P. is grateful to the Resnick Sustainability Institute for generous support of enabling facilities on the Caltech campus. Finally, we acknowledge use of the Beckman Institute Laser Resource Center, which is supported by the Arnold and Mabel Beckman Foundation.

\n
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National Institutes of Health General Medical Sciences. R01 GM-075757 (JCP) National Institutes of Health grant 1S10OD032151-01 (JRW)

\n\n

P.G.-B. and C.G.R. contributed equally. The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.

\n\n\n\n

The authors declare no competing financial interest.

", "abstract": "
\n
\n

Interest in applying proton-coupled electron transfer (PCET) reagents in reductive electro- and photocatalysis requires strategies that mitigate the competing hydrogen evolution reaction. Photoexcitation of a PCET donor to a charge-separated state (CSS) can produce a powerful H-atom donor capable of being electrochemically recycled at a comparatively anodic potential corresponding to its ground state. However, the challenge is designing a mediator with a sufficiently long-lived excited state for bimolecular reactivity. Here, we describe a powerful ferrocene-derived photoelectrochemical PCET mediator exhibiting an unusually long-lived CSS (τ ∼ 0.9 μs). In addition to detailed photophysical studies, proof-of-concept stoichiometric and catalytic proton-coupled reductive transformations are presented, which illustrate the promise of this approach.

\n
\n
", "date": "2024-05-08", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "146", "number": "18", "publisher": "American Chemical Society", "pagerange": "12750-12757", "issn": "0002-7863", "official_url": "https://authors.library.caltech.edu/records/9s5yb-gxz04", "funders": { "items": [ { "grant_number": "R01 GM-075757" }, { "grant_number": "1S10OD032151-01" }, { "grant_number": "Dow Next Generation Educator Fund" }, { "grant_number": "Petroleum Research Fund" }, {}, { "grant_number": "NSF Graduate Research Fellowship" }, {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.4c02610", "pmcid": "PMC11082884", "primary_object": { "basename": "ja4c02610.pdf", "url": "https://authors.library.caltech.edu/records/9s5yb-gxz04/files/ja4c02610.pdf" }, "related_objects": [ { "basename": "ja4c02610_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9s5yb-gxz04/files/ja4c02610_si_001.pdf" } ], "pub_year": "2024", "author_list": "Garrido-Barros, Pablo; Romero, Catherine G.; et al." }, { "id": "https://authors.library.caltech.edu/records/y6nyh-86290", "eprint_status": "archive", "datestamp": "2024-05-16 19:28:59", "lastmod": "2025-04-26 02:52:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Stoerzinger-Kelsey-A", "name": { "family": "Stoerzinger", "given": "Kelsey A." }, "orcid": "0000-0002-3431-8290" }, { "id": "Rao-Reshma", "name": { "family": "Rao", "given": "Reshma" }, "orcid": "0000-0002-6655-3105" }, { "id": "Qiao-Liang", "name": { "family": "Qiao", "given": "Liang" }, "orcid": "0000-0003-2400-2986" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Shao-Horn-Yang", "name": { "family": "Shao-Horn", "given": "Yang" }, "orcid": "0000-0001-8714-2121" } ] }, "title": "Facet-Dependent Oxygen Evolution Reaction Activity of IrO\u2082 from Quantum Mechanics and Experiments", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "

© 2024 American Chemical Society.

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The computational work was supported by the Liquid Sunlight Alliance, which is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award no. DE-SC0021266 (W.A.G.), and by an individual fellowship from the Resnick Sustainability Institute at Caltech (S.K.). This work used Stampede3 at Texas Advanced Computing Center through allocation DMR160114 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, which is supported by National Science Foundation grants #2138259, #2138286, #2138307, #2137603, and #2138296. (W.A.G.). K.A.S. acknowledges support from the National Science Foundation under grant no. 2041153.

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S.K. and K.A.S. contributed equally to this work.

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The authors declare no competing financial interest.

", "abstract": "

The diversity of chemical environments present on unique crystallographic facets can drive dramatic differences in catalytic activity and the reaction mechanism. By coupling experimental investigations of five different IrO2 facets and theory, we characterize the detailed elemental steps of the surface redox processes and the rate-limiting processes for the oxygen evolution reaction (OER). The predicted complex evolution of surface adsorbates and the associated charge transfer as a function of applied potential matches well with the distinct redox features observed experimentally for the five facets. Our microkinetic model from grand canonical quantum mechanics (GC-QM) calculations demonstrates mechanistic differences between nucleophilic attack and O–O coupling across facets, providing the rates as a function of applied potential. These GC-QM calculations explain the higher OER activity observed on the (100), (001), and (110) facets and the lower activity observed for the (101) and (111) facets. This combined study with theory and experiment brings new insights into the structural features that either promote or hinder the OER activity of IrO2, which are expected to provide parallels in structural effects on other oxide surfaces.

", "date": "2024-05-01", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "146", "number": "17", "publisher": "American Chemical Society", "pagerange": "11719\u201311725", "issn": "0002-7863", "official_url": "https://authors.library.caltech.edu/records/y6nyh-86290", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, {}, { "grant_number": "DMR160114" }, { "grant_number": "OAC-2138259" }, { "grant_number": "OAC-2138286" }, { "grant_number": "OAC-2138307" }, { "grant_number": "OAC-2137603" }, { "grant_number": "OAC-2138296" }, { "grant_number": "CBET-2041153" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.3c14271", "primary_object": { "basename": "ja3c14271_si_001.pdf", "url": "https://authors.library.caltech.edu/records/y6nyh-86290/files/ja3c14271_si_001.pdf" }, "pub_year": "2024", "author_list": "Kwon, Soonho; Stoerzinger, Kelsey A.; et al." }, { "id": "https://authors.library.caltech.edu/records/s9bw1-fff98", "eprint_status": "archive", "datestamp": "2024-05-21 21:59:21", "lastmod": "2024-05-21 21:59:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Inglis-Julie", "name": { "family": "Inglis", "given": "Julie" }, "orcid": "0000-0001-9164-7966" }, { "id": "Wallack-Nicole-L", "name": { "family": "Wallack", "given": "Nicole L." }, "orcid": "0000-0003-0354-0187" }, { "id": "Xuan-Jerry-W", "name": { "family": "Xuan", "given": "Jerry W." }, "orcid": "0000-0002-6618-1137" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather" }, "orcid": "0000-0002-5375-4725" }, { "name": { "family": "Chachan", "given": "Yayaati" }, "orcid": "0000-0003-1728-8269" }, { "name": { "family": "Bryan", "given": "Marta L." }, "orcid": "0000-0002-6076-5967" }, { "name": { "family": "Bowler", "given": "Brendan P." }, "orcid": "0000-0003-2649-2288" }, { "name": { "family": "Iyer", "given": "Aishwarya" }, "orcid": "0000-0003-0971-1709" }, { "name": { "family": "Kataria", "given": "Tiffany" }, "orcid": "0000-0003-3759-9080" }, { "name": { "family": "Benneke", "given": "Bj\u00f6rn" }, "orcid": "0000-0001-5578-1498" } ] }, "title": "Atmospheric Retrievals of the Young Giant Planet ROXs 42B b from Low- and High-resolution Spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

\n\n

This research was carried out at the Jet Propulsion Laboratory and the California Institute of Technology under a contract with the National Aeronautics and Space Administration and funded through the President's and Director's Research & Development Fund Program. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

\n\n

numpy (Harris et al. 2020), scipy (Virtanen et al. 2020), matplotlib (Hunter 2007), astropy (Astropy Collaborationet al. 2013, 2018; Astropy Collaboration 2022), dynesty (Koposov et al. 2023), pymultinest, pycuba, (Buchneret al. 2014), (Virtanen et al. 2020), petitRADTRANS (Mollière et al. 2019)

", "abstract": "
\n

Previous attempts have been made to characterize the atmospheres of directly imaged planets at low resolution (R ∼ 10–100 s), but the presence of clouds has often led to degeneracies in the retrieved atmospheric abundances with cloud opacity and temperature structure that bias retrieved compositions. In this study, we perform retrievals on the ultrayoung (\u22725 Myr) directly imaged planet ROXs 42B b with both a downsampled low-resolution JHK-band spectrum from Gemini/NIFS and Keck/OSIRIS, and a high-resolution K-band spectrum from pre-upgrade Keck/NIRSPAO. Using the atmospheric retrieval framework of petitRADTRANS, we analyze both data sets individually and combined. We additionally fit for the stellar abundances and other physical properties of the host stars, a young M spectral type binary, using the SPHINX model grid. We find that the measured C/O, 0.50 ± 0.05, and metallicity, [Fe/H] = −0.67 ± 0.35, for ROXs 42B b from our high-resolution spectrum agree with those of its host stars within 1σ. The retrieved parameters from the high-resolution spectrum are also independent of our choice of cloud model. In contrast, the retrieved parameters from the low-resolution spectrum show strong degeneracies between the clouds and the retrieved metallicity and temperature structure. When we retrieve both data sets together, we find that these degeneracies are reduced but not eliminated, and the final results remain highly sensitive to cloud modeling choices. We conclude that high-resolution spectroscopy offers the most promising path for reliably determining atmospheric compositions of directly imaged companions independent of their cloud properties.

\n
", "date": "2024-05", "date_type": "published", "publication": "Astronomical Journal", "volume": "167", "number": "5", "publisher": "American Astronomical Society", "pagerange": "218", "issn": "0004-6256", "official_url": "https://authors.library.caltech.edu/records/s9bw1-fff98", "funders": { "items": [ { "grant_number": "President and Director's Research and Development Fund" }, {}, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/1538-3881/ad2771", "primary_object": { "basename": "Inglis_2024_AJ_167_218.pdf", "url": "https://authors.library.caltech.edu/records/s9bw1-fff98/files/Inglis_2024_AJ_167_218.pdf" }, "pub_year": "2024", "author_list": "Inglis, Julie; Wallack, Nicole L.; et al." }, { "id": "https://authors.library.caltech.edu/records/gddvz-x4m22", "eprint_status": "archive", "datestamp": "2024-06-14 20:51:50", "lastmod": "2024-06-14 20:52:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Yu", "given": "Shen\u2010Wei" } }, { "name": { "family": "Kwon", "given": "Soonho" } }, { "name": { "family": "Chen", "given": "Yizhen" }, "orcid": "0000-0002-8499-2013" }, { "name": { "family": "Xie", "given": "Zhenhua" } }, { "name": { "family": "Lu", "given": "Xiner" } }, { "name": { "family": "He", "given": "Kai" } }, { "name": { "family": "Hwang", "given": "Sooyeon" } }, { "name": { "family": "Chen", "given": "Jingguang G." } }, { "name": { "family": "Goddard", "given": "William A." } }, { "name": { "family": "Zhang", "given": "Sen" }, "orcid": "0000-0002-1716-3741" } ] }, "title": "Construction of a Pt\u2010CeO\u2093 Interface for the Electrocatalytic Hydrogen Evolution Reaction", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Authors. Advanced Functional Materials published byWiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the originalwork is properly cited, the use is non-commercial and no modificationsor adaptations are made

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S.Y., S.K. and Y.C. contributed equally to this work. This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division (DE-SC00234430). This research used resources of the Center for Functional Nanomaterials (CFN) and beamlines 7-BM (QAS) of the National Synchrotron Light Source II (NSLS-II) at Brookhaven National Laboratory (Contract No. DE-SC0012704 and DE-SC0012653), U.S. DOE Office of Science User Facilities. S. Z. acknowledges support from the Sloan Research Fellowship (Grant No. FG-2022-18460). S.K. acknowledges support from the Resnick Sustainability Institute at Caltech. This work used Stampede3 at Texas Advanced Computing Center through allocation DMR160114 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, which is supported by National Science Foundation grants #2138259, #2138286, #2138307, #2137603, and #2138296. K.H. and X. L. acknowledge the support from the American Chemical Society Petroleum Research Fund under Grant No. 62493-DNI10, as well as the use of facilities and instrumentation at the University of California Irvine Materials Research Institute, supported in part by the National Science Foundation Materials Research Science and Engineering Center program through the University of California Irvine Center for Complex and Active Materials (DMR-2011967).

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The data that support the findings of this study are available from the corresponding author upon reasonable request.

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Supporting information
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Supplementary Movie S1
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The authors declare no conflict of interest.

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This article also appears in:

\n", "abstract": "AbstractThe creation of metal\u2010metal oxide interfaces is an important approach to fine\u2010tuning catalyst properties through strong interfacial interactions. This article presents the work on developing interfaces between Pt and CeOx that improve Pt surface energetics for the hydrogen evolution reaction (HER) within an alkaline electrolyte. The Pt\u2010CeOx interfaces are formed by depositing size\u2010controlled Pt nanoparticles onto a carbon support already coated with ultrathin CeOx nanosheets. This interface structure facilitates substantial electron transfer from Pt to CeOx, resulting in decreased hydrogen binding energies on Pt surfaces, and water dissociation for the HER, as predicted by the density functional theory (DFT) calculations. Electrochemical testing indicates that both Pt specific activity and mass activity are improved by a factor of 2 to 3 following the formation of Pt\u2010CeOx interfaces. This study underscores the significance and potential of harnessing robust interfacial effects to enhance electrocatalytic reactions.", "date": "2024-04-19", "date_type": "published", "publication": "Advanced Functional Materials", "publisher": "Wiley", "pagerange": "2402966", "issn": "1616-301X", "official_url": "https://authors.library.caltech.edu/records/gddvz-x4m22", "funders": { "items": [ { "grant_number": "DE\u2010SC00234430" }, { "grant_number": "DE\u2010SC0012704" }, { "grant_number": "DE\u2010SC0012653" }, { "grant_number": "FG\u20102022\u201018460" }, {}, { "grant_number": "DMR160114" }, { "grant_number": "OAC-2138259" }, { "grant_number": "OAC-2138286" }, { "grant_number": "OAC-2138307" }, { "grant_number": "OAC-2137603" }, { "grant_number": "OAC-2138296" }, { "grant_number": "62493-DNI10" }, { "grant_number": "DMR-2011967" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/adfm.202402966", "primary_object": { "basename": "Adv Funct Materials - 2024 - Yu - Construction of a Pt\u2010CeOx Interface for the Electrocatalytic Hydrogen Evolution Reaction.pdf", "url": "https://authors.library.caltech.edu/records/gddvz-x4m22/files/Adv Funct Materials - 2024 - Yu - Construction of a Pt\u2010CeOx Interface for the Electrocatalytic Hydrogen Evolution Reaction.pdf" }, "related_objects": [ { "basename": "adfm202402966-sup-0002-movies1.mp4", "url": "https://authors.library.caltech.edu/records/gddvz-x4m22/files/adfm202402966-sup-0002-movies1.mp4" }, { "basename": "adfm202402966-sup-0001-suppmat.docx", "url": "https://authors.library.caltech.edu/records/gddvz-x4m22/files/adfm202402966-sup-0001-suppmat.docx" } ], "pub_year": "2024", "author_list": "Yu, Shen\u2010Wei; Kwon, Soonho; et al." }, { "id": "https://authors.library.caltech.edu/records/e1mhw-3ws90", "eprint_status": "archive", "datestamp": "2024-04-10 22:58:29", "lastmod": "2025-10-29 15:26:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Johnson", "given": "Aaron D." }, "orcid": "0000-0002-7445-8423" }, { "id": "Chatziioannou-K", "name": { "family": "Chatziioannou", "given": "Katerina" }, "orcid": "0000-0002-5833-413X" }, { "name": { "family": "Farr", "given": "Will M." }, "orcid": "0000-0003-1540-8562" } ] }, "title": "Source confusion from neutron star binaries in ground-based gravitational wave detectors is minimal", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 American Physical Society.

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We thank Isaac Legred for providing data for the SFHo equation of state. We thank Neil Cornish for discussions about source confusion in the context of LISA and a review of the manuscript. We acknowledge support from the Caltech and Jet Propulsion Laboratory President’s and Director’s Fund and the Sloan Foundation. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.

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", "abstract": "

Upgrades beyond the current second generation of ground-based gravitational wave detectors will allow them to observe tens of thousands neutron star and black hole binaries. Given the typical minute-to-hour duration of neutron star signals in the detector frequency band, a number of them will overlap in the time-frequency plane, resulting in a nonzero cross-correlation. We examine “source confusion” arising from overlapping signals whose time-frequency tracks cross. Adopting the median observed merger rate of 100  Gpc\u207b³ yr\u207b¹, each neutron star binary signal overlaps with an average of 42(4)[0.5] other signals when observed from 2(5)[10] Hz. The vast majority of overlaps occur at low frequencies where the inspiral evolution is slow: 91% of time-frequency overlaps occur in band below 5 Hz. The combined effect of overlapping signals does not satisfy the central limit theorem and source confusion cannot be treated as stationary, Gaussian noise: on average 0.91(0.17)[0.05] signals are present in a single adaptive time-frequency bin centered at 2(5)[10] Hz. We quantify source confusion under a realistic neutron star binary population and find that parameter uncertainty typically increases by less than 1% unless there are overlapping signals whose detector-frame chirp mass difference is \u22720.01 M_\u2299 and the overlap frequency is \u227340  Hz. Out of 1 × 10\u2076 simulated signals, 0.14% fall within this region of detector-frame chirp mass differences, but their overlap frequencies are typically lower than 40 Hz. Source confusion for ground-based detectors, where events overlap instantaneously, is significantly milder than the equivalent Laser Interferometer Space Antenna problem, where many classes of events overlap for the lifetime of the mission.

", "date": "2024-04-15", "date_type": "published", "publication": "Physical Review D", "volume": "109", "number": "8", "publisher": "American Physical Society", "pagerange": "084015", "issn": "2470-0010", "official_url": "https://authors.library.caltech.edu/records/e1mhw-3ws90", "funders": { "items": [ { "grant_number": "President's and Director's Fund" }, { "grant_number": "President's and Director's Fund" }, {}, {} ] }, "local_group": { "items": [ { "id": "Space-Astrophysics-Laboratory" }, { "id": "TAPIR" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "LIGO" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevd.109.084015", "primary_object": { "basename": "PhysRevD.109.084015.pdf", "url": "https://authors.library.caltech.edu/records/e1mhw-3ws90/files/PhysRevD.109.084015.pdf" }, "pub_year": "2024", "author_list": "Johnson, Aaron D.; Chatziioannou, Katerina; et al." }, { "id": "https://authors.library.caltech.edu/records/3nc5y-wq154", "eprint_status": "archive", "datestamp": "2024-04-17 20:19:02", "lastmod": "2025-04-23 15:30:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Watkins", "given": "Nicholas B." }, "orcid": "0000-0001-7251-9387" }, { "name": { "family": "Lai", "given": "Yungchieh" } }, { "name": { "family": "Schiffer", "given": "Zachary J." }, "orcid": "0000-0001-6069-8613" }, { "name": { "family": "Canestraight", "given": "Virginia M." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Electrode Surface Heating with Organic Films Improves CO\u2082 Reduction Kinetics on Copper", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

\n\n
\n

This material is primarily based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. The Resnick Sustainability Institute at Caltech is acknowledged for its support of enabling infrastructure and facilities. We thank Florian Grass for many productive conversations.

\n
\n\n

N.B.W. and Y.L. contributed equally to this work.

\n\n

The authors declare no competing financial interest.

\n\n", "abstract": "
\n

Management of the electrode surface temperature is an understudied aspect of (photo)electrode reactor design for complex reactions, such as CO2 reduction. In this work, we study the impact of local electrode heating on electrochemical reduction of CO2 reduction. Using the ferri/ferrocyanide open circuit voltage as a reporter of the effective reaction temperature, we reveal how the interplay of surface heating and convective cooling presents an opportunity for cooptimizing mass transport and thermal assistance of electrochemical reactions, where we focus on reduction of CO2 to carbon-coupled (C2+) products. The introduction of an organic coating on the electrode surface facilitates well-behaved electrode kinetics with near-ambient bulk electrolyte temperature. This approach helps to probe the fundamentals of thermal effects in electrochemical reactions, as demonstrated through Bayesian inference of Tafel kinetic parameters from a suite of high throughput experiments, which reveal a decrease in overpotential for C2+ products by 0.1 V on polycrystalline copper via 60 °C surface heating.

\n
", "date": "2024-04-12", "date_type": "published", "publication": "ACS Energy Letters", "volume": "9", "number": "4", "publisher": "American Chemical Society", "pagerange": "1440-1445", "issn": "2380-8195", "official_url": "https://authors.library.caltech.edu/records/3nc5y-wq154", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, {} ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.4c00204", "pmcid": "PMC11019637", "primary_object": { "basename": "nz4c00204.pdf", "url": "https://authors.library.caltech.edu/records/3nc5y-wq154/files/nz4c00204.pdf" }, "related_objects": [ { "basename": "nz4c00204_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3nc5y-wq154/files/nz4c00204_si_001.pdf" } ], "pub_year": "2024", "author_list": "Watkins, Nicholas B.; Lai, Yungchieh; et al." }, { "id": "https://authors.library.caltech.edu/records/5cg7f-40468", "eprint_status": "archive", "datestamp": "2024-04-10 16:15:49", "lastmod": "2024-04-10 16:15:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Palmer-Levi-Daniel", "name": { "family": "Palmer", "given": "Levi Daniel" }, "orcid": "0000-0002-7228-4263" }, { "id": "Lee-Wonseok", "name": { "family": "Lee", "given": "Wonseok" }, "orcid": "0000-0003-1077-0511" }, { "id": "Dong-Chung-Li", "name": { "family": "Dong", "given": "Chung-Li" }, "orcid": "0000-0002-4289-4677" }, { "id": "Liu-Ru-Shi", "name": { "family": "Liu", "given": "Ru-Shi" }, "orcid": "0000-0002-1291-9052" }, { "id": "Wu-Nianqiang", "name": { "family": "Wu", "given": "Nianqiang" }, "orcid": "0000-0002-8888-2444" }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott Kevin" }, "orcid": "0000-0003-3538-2259" } ] }, "title": "Determining Quasi-Equilibrium Electron and Hole Distributions of Plasmonic Photocatalysts Using Photomodulated X-ray Absorption Spectroscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Engineering; General Materials Science", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

\n\n
\n

We thank Jonathan Michelsen and Hanzhe Liu for providing guidance and MATLAB scripts to perform the OCEAN calculations. Additionally, we thank Alex Krotz for modifying the OCEAN code to incorporate photoexcited holes. The computations presented here were conducted in the Resnick High Performance Computing Center, a Resnick Sustainability Institute facility at the California Institute of Technology. This research also used resources of the National Energy Research Scientific Computing Center, a Department of Energy (DOE) Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract No. DE-AC02-05CH11231 using NERSC award BES-ERCAP0024109.

\n
\n\n

A portion of this work was supported by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award No. DE-SC0021266. L.D.P. is supported by an NSF Graduate Research Fellowship under Grant No. DGE-1745301. W.L. acknowledges further support from the Korea Foundation for Advanced Studies. The Resnick Sustainability Institute at the California Institute of Technology supports the Resnick High Performance Computing Center. R.S.L. acknowledges financial support by the National Science and Technology Council of Taiwan (NSTC 109-2113-M-002-020-MY3), and the “Advanced Research Center For Green Materials Science and Technology” from The Featured Area Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education (112L9006).

\n\n

L.D.P. and S.K.C. conceived the research outlook and direction. L.D.P. performed the data analysis and theoretical modeling/simulations. L.D.P. interpreted the results and wrote the manuscript. W.L. supported the theoretical development, data interpretation, and writing. S.K.C. synthesized and characterized the core–shell nanoparticles. C.L.D. and R.S.L. collected the experimental X-ray data. N.W. directed initial project direction and collaboration. S.K.C. acquired project funding and directed the project. All authors have given approval to the final version of the manuscript.

\n
\n
 
\n
\n\n

The authors declare no competing financial interest.

\n\n", "abstract": "
\n

Most photocatalytic and photovoltaic devices operate under broadband, constant illumination. Electron and hole dynamics in these devices, however, are usually measured by using ultrafast pulsed lasers in a narrow wavelength range. In this work, we use excited-state X-ray theory originally developed for transient X-ray experiments to study steady-state photomodulated X-ray spectra. We use this method to attempt to extract electron and hole distributions from spectra collected at a nontime-resolved synchrotron beamline. A set of plasmonic metal core–shell nanoparticles is designed as the control experiment because they can systematically isolate photothermal, hot electron, and thermalized electron–hole pairs in a TiO2 shell. Steady-state changes in the Ti L2,3 edge are measured with and without continuous-wave illumination of the nanoparticle’s localized surface plasmon resonance. The results suggest that within error the quasi-equilibrium carrier distribution can be determined even from relatively noisy data with mixed excited-state phenomena. Just as importantly, the theoretical analysis of noisy data is used to provide guidelines for the beamline development of photomodulated steady-state spectroscopy.

\n
", "date": "2024-04-02", "date_type": "published", "publication": "ACS Nano", "volume": "18", "number": "13", "publisher": "American Chemical Society", "pagerange": "9344-9353", "issn": "1936-0851", "official_url": "https://authors.library.caltech.edu/records/5cg7f-40468", "funders": { "items": [ { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "BES-ERCAP0024109" }, { "grant_number": "DE-SC0021266" }, { "grant_number": "DGE-1745301" }, {}, {}, { "grant_number": "109-2113-M-002-020-MY3" }, { "grant_number": "112L9006" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1021/acsnano.3c08181", "pmcid": "PMC10993415", "primary_object": { "basename": "nn3c08181.pdf", "url": "https://authors.library.caltech.edu/records/5cg7f-40468/files/nn3c08181.pdf" }, "related_objects": [ { "basename": "nn3c08181_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5cg7f-40468/files/nn3c08181_si_001.pdf" } ], "pub_year": "2024", "author_list": "Palmer, Levi Daniel; Lee, Wonseok; et al." }, { "id": "https://authors.library.caltech.edu/records/7n6tw-r0s23", "eprint_status": "archive", "datestamp": "2024-05-03 17:08:26", "lastmod": "2024-05-03 17:08:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yeh-Christopher", "name": { "family": "Yeh", "given": "Christopher" }, "orcid": "0000-0002-7624-6168" }, { "id": "Yu-Jing", "name": { "family": "Yu", "given": "Jing" }, "orcid": "0000-0003-1318-0189" }, { "id": "Shi-Yuanyuan", "name": { "family": "Shi", "given": "Yuanyuan" }, "orcid": "0000-0002-6182-7664" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" }, "orcid": "0000-0002-5923-0199" } ] }, "title": "Online Learning for Robust Voltage Control Under Uncertain Grid Topology", "ispublished": "pub", "full_text_status": "public", "keywords": "General Computer Science", "note": "

This work is licensed under a Creative Commons Attribution 4.0 License. 

\n\n

We thank Dimitar Ho for useful conversations. This work was supported by the Caltech Resnick Sustainability Institute, two Caltech/Amazon AWS AI4Science fellowships, and National Science Foundation grants CNS-2146814, CNS-2106403, CPS-2136197, ECCS-2200692, and NGSDI-2105648.

", "abstract": "
\n
\n
\n
Voltage control generally requires accurate information about the grid’s topology in order to guarantee network stability. However, accurate topology identification is challenging for existing methods, especially as the grid is subject to increasingly frequent reconfiguration due to the adoption of renewable energy. In this work, we combine a nested convex body chasing algorithm with a robust predictive controller to achieve provably finite-time convergence to safe voltage limits in the online setting where there is uncertainty in both the network topology as well as load and generation variations. In an online fashion, our algorithm narrows down the set of possible grid models that are consistent with observations and adjusts reactive power generation accordingly to keep voltages within desired safety limits. Our approach can also incorporate existing partial knowledge of the network to improve voltage control performance. We demonstrate the effectiveness of our approach in a case study on a Southern California Edison 56-bus distribution system. Our experiments show that in practical settings, the controller is indeed able to narrow the set of consistent topologies quickly enough to make control decisions that ensure stability in both linearized and realistic non-linear models of the distribution grid.
\n
\n
\n
", "date": "2024-04-01", "date_type": "published", "publication": "IEEE Transactions on Smart Grid", "publisher": "IEEE", "issn": "1949-3053", "official_url": "https://authors.library.caltech.edu/records/7n6tw-r0s23", "funders": { "items": [ {}, { "agency": "Caltech / Amazon AWS AI4Science Fellowship" }, { "grant_number": "CNS-2106403" }, { "grant_number": "CNS-2146814" }, { "grant_number": "ECCS-2136197" }, { "grant_number": "ECCS-2200692" }, { "grant_number": "CNS-2105648" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "AWS-Center-for-Quantum-Computing" } ] }, "doi": "10.1109/tsg.2024.3383804", "primary_object": { "basename": "Online_Learning_for_Robust_Voltage_Control_Under_Uncertain_Grid_Topology.pdf", "url": "https://authors.library.caltech.edu/records/7n6tw-r0s23/files/Online_Learning_for_Robust_Voltage_Control_Under_Uncertain_Grid_Topology.pdf" }, "pub_year": "2024", "author_list": "Yeh, Christopher; Yu, Jing; et al." }, { "id": "https://authors.library.caltech.edu/records/wxj9m-gez95", "eprint_status": "archive", "datestamp": "2024-06-14 21:08:06", "lastmod": "2024-06-14 21:08:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "A Model for Thaw and Erosion of Permafrost Riverbanks", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024. American Geophysical Union.

\n\n
\n

The authors would like to thank the Koyukon Athabascans, Chief Carl Burgett, and the Huslia Tribal Council for access to their land, and USFWS Koyukuk National Wildlife Refuge for research permitting and logistical assistance. We acknowledge Shawn Huffman, Alvin Attla, Darin Dayton, Charlene Mayo, Mary Ann Sam, and Virgil Umphenour for field logistical support and local expertise. We would also like to thank Rain Blankenship, Austin Chadwick, Hannah Dion-Kirshner, Kieran Dunne, Emily Geyman, Yutian Ke, Preston C. Kemeny, Gen K. Li, John Magyar, Edda Mutter, Justin Nghiem, Anastasia Piliouras, Jocelyn Reahl, Joel Rowland, Jon Schwenk, Emily Seelen, Isabel Smith, Josh West, and Lisa Winter for assistance in collecting field data; Kim Litwin Miller, Bill Dietrich, Chris Paola, and the Caltech 2018 Ge126 course for fruitful discussions; and editor Marisa Repasch as well as Kun Zhao and three anonymous reviewers for their helpful feedback. In addition, the authors acknowledge funding from the Resnick Sustainability Institute at Caltech, NSF Awards 2127442 and 2031532, and the National Defense Science and Engineering Graduate Fellowship.

\n
\n\n
\n
\n\n\n

Data for permafrost probe measurements are available in the Supporting Information and at Douglas, Blankenship, et al. (2023). Soil bulk density and water content data are available from Douglas et al. (2022). Data for ground temperature at Huslia (site ID US O-82) from the Global Terrestrial Network for Permafrost (GTN-P) Database from Biskaborn et al. (2015). Model scripts are available at M. M. Douglas (2023).

\n

Supporting information S1

\n\n
\n
", "abstract": "
\n

How will bank erosion rates in Arctic rivers respond to a warming climate? Existing physical models predict that bank erosion rates should increase with water temperature as permafrost thaws more rapidly. However, the same theory predicts much faster erosion than is typically observed. We propose that these models are missing a key component: a layer of thawed sediment on the bank that buffers heat transfer and slows erosion. We developed a 1D model for this thawed layer, which reveals three regimes for permafrost riverbank erosion. Thaw-limited erosion occurs in the absence of a thawed layer, such that rapid pore-ice melting sets the pace of erosion, consistent with existing models. Entrainment-limited erosion occurs when pore-ice melting outpaces bank erosion, resulting in a thawed layer, and the relatively slow entrainment of sediment sets the pace of erosion similar to non-permafrost rivers. Third, the intermediate regime occurs when the thawed layer goes through cycles of thickening and failure, leading to a transient thermal buffer that slows thaw rates. Distinguishing between these regimes is important because thaw-limited erosion is highly sensitive to water temperature, whereas entrainment-limited erosion is not. Interestingly, the buffered regime produces a thawed layer and relatively slow erosion rates like the entrainment-limited regime, but erosion rates are temperature sensitive like the thaw-limited regime. The results suggest the potential for accelerating erosion in a warming Arctic where bank erosion is presently thaw-limited or buffered. Moreover, rivers can experience all regimes annually and transition between regimes with warming, altering their sensitivity to climate change.

\n
", "date": "2024-04", "date_type": "published", "publication": "Journal of Geophysical Research: Earth Surface", "volume": "129", "number": "4", "publisher": "American Geophysical Union", "pagerange": "e2023JF007452", "issn": "2169-9003", "official_url": "https://authors.library.caltech.edu/records/wxj9m-gez95", "funders": { "items": [ {}, { "grant_number": "EAR-2127442" }, { "grant_number": "EAR-2031532" }, { "grant_number": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2023jf007452", "primary_object": { "basename": "JGR Earth Surface - 2024 - Douglas - A Model for Thaw and Erosion of Permafrost Riverbanks.pdf", "url": "https://authors.library.caltech.edu/records/wxj9m-gez95/files/JGR Earth Surface - 2024 - Douglas - A Model for Thaw and Erosion of Permafrost Riverbanks.pdf" }, "related_objects": [ { "basename": "2023jf007452-sup-0001-supporting information si-s01.pdf", "url": "https://authors.library.caltech.edu/records/wxj9m-gez95/files/2023jf007452-sup-0001-supporting information si-s01.pdf" } ], "pub_year": "2024", "author_list": "Douglas, Madison M. and Lamb, Michael P." }, { "id": "https://authors.library.caltech.edu/records/0hz5b-mrn94", "eprint_status": "archive", "datestamp": "2024-05-23 21:29:06", "lastmod": "2025-04-24 20:38:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeichner-Sarah-S", "name": { "family": "Zeichner", "given": "Sarah S." }, "orcid": "0000-0001-8897-7657" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Lotem-Noam", "name": { "family": "Lotem", "given": "Noam" }, "orcid": "0000-0001-5079-7482" }, { "id": "Moore-Kelsey-R", "name": { "family": "Moore", "given": "Kelsey R." }, "orcid": "0000-0002-4905-9623" }, { "id": "Goldford-Joshua-E", "name": { "family": "Goldford", "given": "Joshua E." }, "orcid": "0000-0001-7315-8018" }, { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John M." }, "orcid": "0000-0001-5768-7593" } ] }, "title": "The Carbon Isotopic Composition of Archean Kerogen and Its Resilience Through the Rock Cycle", "ispublished": "pub", "full_text_status": "public", "note": "

This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CCBY-NC-ND-4.0). View this license’s legal deed at https://creativecommons.org/licenses/by-nc-nd/4.0 and legal code at https://creativecommons.org/licenses/by-nc-nd/4.0/legalcode for more information.

\n\n

We thank the following individuals for conversations that have contributed to various stages of this project: Tanja Bosak, Guannan Dong, Katherine Freeman, Katherine French, Nami Kitchen, Usha Lingappa, Max Lloyd, Gordon Love, Juliet Ryan-Davis, NiveditaThiagarajan, Jasmina Wiemann, and Hao Xie. We are grateful to Alex Sessions, Jordon Hemingway, Stephen Mojzsis, and the anonymous Reviewer for their suggestions in the revision process. Thanks to Karen Craddock, Diane Giroux, Ethel Liske, and Trevor Teed for conversations regarding the history and naming of the “Slave Craton” and how Earth scientists can work to improve how we approach the intersection of our work with indigenous tradition, and other communities more broadly. S.S.Z. was supported by the NSF Graduate Research Fellowship, the Simons Foundation, and the Resnick Sustainability Institute. This work was conducted on the ancestral lands of the Gabrielino-Tongva and Chumash people.

\n\n

S.S.Z. conceived of the project, performed the literature review, compiled and analyzed the data, designed the mechanistic model, and wrote the paper. W.W.F. participated in investigation, data analysis, interpretation, and paper revisions. N.L. aided in designing the mechanistic model and collating the data compilation. K.R.M. compiled data related to taphonomy and sedimentology and wrote the related sections. J.E.G. contributed interpretation with regards to biological implications of this study. J.M.E. participated in investigation, data analysis, interpretation, mechanistic model design, and paper revisions.

\n\n

The full data compilation for this study, as well as the spreadsheet associated with the maturation model can be found in a GitHub repository (Zeichner, 2023). Additional materials and methods for the model, and supplemental table and figures are included in a supplementary document.

\n

Supplementary Document

\n

https://doi.org/10.5281/zenodo.8280728

", "abstract": "

The Archean rock record is limited and there is minimal organic matter available to understand the origin and evolution of life on early Earth. Low carbon isotope ratios have been measured in organic and reduced carbon phases in Archean rocks and have been invoked as biosignatures. However, it can be challenging to distinguish whether these low values reflect biotic formation, abiotic reactions, or post-depositional processes. To re-address this long-standing question, we compiled a comprehensive dataset of carbon isotope ratio measurements from organic carbon phases from Archean units that were analyzed using a variety of geochemical techniques. Our compilation also includes available descriptions and measurements of the stratigraphy, mineralogy, elemental ratios, and metamorphic grade for each data point. Our statistical analyses re-enforce a result that has been noted by prior compilations, that the carbon isotopic composition of Archean organic matter (OM) is broadly more 13C-deplete than the composition of Phanerozoic OM: The median \ud835\udeff13C values (±SD) of Archean total organic carbon and kerogen were −30.5±8‰ (n=2421) and −33.7±11.3‰ (n=556; Phanerozoic OM \ud835\udeff13C±SD = −26.7±4.6‰ with n=449 from a prior compilation). Our study also identifies a previously unrecognized bimodality within the \ud835\udeff13C values of Archean OM that is observed even with subsampling of the data to account for geographic and stratigraphic sampling bias. We describe and model the isotopic and structural changes associated with the transformation of marine Type II kerogen from formation through diagenesis, catagenesis and metagenesis, and metamorphism, as described by trends on a van Krevelin diagram. Empirically, early maturation of organic matter during diagenesis results in shifts up to a few per-mille, which can occur in either direction depending on selective preservation and degradation of compounds. Thermal cracking that occurs during catagenesis can drive increases in \ud835\udeff13C of 5–12‰. At temperatures above greenschist metamorphism, carbon atoms exchange with other reactive carbon pools, driving increases in \ud835\udeff13C of up to 20‰. Together, our analyses suggest that the most metamorphosed graphitic samples from the earliest Archean are likely signatures of alteration, while low and multimodal ranges of \ud835\udeff13C values may preserve records of Archean ecology.

", "date": "2024-04", "date_type": "published", "publication": "American Journal of Science", "volume": "324", "publisher": "American Journal of Science", "pagerange": "8", "issn": "1945-452X", "official_url": "https://authors.library.caltech.edu/records/0hz5b-mrn94", "funders": { "items": [ { "grant_number": "NSF Graduate Research Fellowship" }, {}, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.2475/001c.116058", "primary_object": { "basename": "supplemental_materials_for_zeichner_et_al_final_with_refs.docx", "url": "https://authors.library.caltech.edu/records/0hz5b-mrn94/files/supplemental_materials_for_zeichner_et_al_final_with_refs.docx" }, "related_objects": [ { "basename": "116058-the-carbon-isotopic-composition-of-archean-kerogen-and-its-resilience-through-the-rock-cycle.pdf", "url": "https://authors.library.caltech.edu/records/0hz5b-mrn94/files/116058-the-carbon-isotopic-composition-of-archean-kerogen-and-its-resilience-through-the-rock-cycle.pdf" } ], "pub_year": "2024", "author_list": "Zeichner, Sarah S.; Fischer, Woodward W.; et al." }, { "id": "https://authors.library.caltech.edu/records/f9r1z-7qw16", "eprint_status": "archive", "datestamp": "2024-04-10 21:20:25", "lastmod": "2024-04-10 21:20:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krasley-Andrew-T", "name": { "family": "Krasley", "given": "Andrew T." } }, { "id": "Li-Eugene", "name": { "family": "Li", "given": "Eugene" } }, { "id": "Galeana-Jesus-M", "name": { "family": "Galeana", "given": "Jesus M." }, "orcid": "0009-0006-1974-6664" }, { "id": "Bulumulla-Chandima", "name": { "family": "Bulumulla", "given": "Chandima" }, "orcid": "0000-0003-0324-2008" }, { "id": "Beyene-Abraham-G", "name": { "family": "Beyene", "given": "Abraham G." }, "orcid": "0000-0003-3896-2144" }, { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" } ] }, "title": "Carbon Nanomaterial Fluorescent Probes and Their Biological Applications", "ispublished": "pub", "full_text_status": "public", "keywords": "General Chemistry", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

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G.S.D. acknowledges funding from Caltech, Resnick Sustainability Institute, Henry Luce Foundation, Shurl and Curci Foundation, NSF, and NASA. A.G.B. acknowledges funding from the Howard Hughes Medical Institute.

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Andrew T. Krasley and Eugene Li contributed equally to this work as co-first authors, and Jesus M. Galeana and Chandima Bulumulla contributed equally to this work as co-second authors. Abraham G. Beyene and Gozde S. Demirer are co-corresponding authors. All authors contributed to writing and editing of the paper, and approved the final version. CRediT: Andrew T. Krasley data curation, formal analysis, investigation, methodology, resources, software, validation, visualization, writing-original draft, writing-review & editing; Eugene Li data curation, formal analysis, investigation, methodology, resources, software, validation, visualization, writing-original draft, writing-review & editing; Jesus M. Galeana data curation, formal analysis, investigation, methodology, resources, software, validation, visualization, writing-original draft, writing-review & editing; Chandima Bulumulla data curation, formal analysis, investigation, methodology, resources, software, validation, visualization, writing-original draft, writing-review & editing; Abraham G. Beyene conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, resources, software, supervision, validation, visualization, writing-original draft, writing-review & editing; Gözde S. Demirer conceptualization, data curation, formal analysis, funding acquisition, investigation, methodology, project administration, resources, software, supervision, validation, visualization, writing-original draft, writing-review & editing.

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The authors declare no competing financial interest.

", "abstract": "
\n

Fluorescent carbon nanomaterials have broadly useful chemical and photophysical attributes that are conducive to applications in biology. In this review, we focus on materials whose photophysics allow for the use of these materials in biomedical and environmental applications, with emphasis on imaging, biosensing, and cargo delivery. The review focuses primarily on graphitic carbon nanomaterials including graphene and its derivatives, carbon nanotubes, as well as carbon dots and carbon nanohoops. Recent advances in and future prospects of these fields are discussed at depth, and where appropriate, references to reviews pertaining to older literature are provided.

\n
", "date": "2024-03-27", "date_type": "published", "publication": "Chemical Reviews", "volume": "124", "number": "6", "publisher": "American Chemical Society", "pagerange": "3085-3185", "issn": "0009-2665", "official_url": "https://authors.library.caltech.edu/records/f9r1z-7qw16", "funders": { "items": [ {}, {}, {}, {}, {}, {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemrev.3c00581", "pmcid": "PMC10979413", "primary_object": { "basename": "cr3c00581.pdf", "url": "https://authors.library.caltech.edu/records/f9r1z-7qw16/files/cr3c00581.pdf" }, "pub_year": "2024", "author_list": "Krasley, Andrew T.; Li, Eugene; et al." }, { "id": "https://authors.library.caltech.edu/records/zfkbv-w7v86", "eprint_status": "archive", "datestamp": "2024-05-03 16:49:59", "lastmod": "2025-04-26 02:53:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Choi-Chungseok", "name": { "family": "Choi", "given": "Chungseok" }, "orcid": "0000-0001-9169-1393" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Gao-Yuanzuo", "name": { "family": "Gao", "given": "Yuanzuo" } }, { "id": "Cheon-Seonjeong", "name": { "family": "Cheon", "given": "Seonjeong" }, "orcid": "0000-0002-2838-6959" }, { "id": "Li-Jing", "name": { "family": "Li", "given": "Jing" }, "orcid": "0000-0001-7538-246X" }, { "id": "Menges-Fabian", "name": { "family": "Menges", "given": "Fabian" }, "orcid": "0000-0002-5859-9197" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Wang-Hailiang", "name": { "family": "Wang", "given": "Hailiang" }, "orcid": "0000-0003-4409-2034" } ] }, "title": "CO\u2082-Promoted Electrocatalytic Reduction of Chlorinated Hydrocarbons", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "

© 2024 American Chemical Society.

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This work was supported by the U.S. National Science Foundation (grant CBET2028351). W.A.G. acknowledges support by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266 (computational work). This work used the Extreme Science and Engineering Discovery Environment (XSEDE) for DFT calculations, which is supported by National Science Foundation grant number ACI-1548562. S.K. acknowledges the Resnick Sustainability Institute at Caltech for an individual fellowship (computational work).

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U.S. National Science Foundation (grant CBET2028351)

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Liquid Sunlight Alliance, supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266

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National Science Foundation grant number ACI-1548562

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Resnick Sustainability Institute at Caltech

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Experimental and computational details, and additional structural characterization, electrochemical reaction, in situ Raman spectroscopy, and DFT calculation results (PDF)

", "abstract": "

Electrochemical reactions and their catalysis are important for energy and environmental applications, such as carbon neutralization and water purification. However, the synergy in electrocatalysis between CO2 utilization and wastewater treatment has not been explored. In this study, we find that the electrochemical reduction of chlorinated organic compounds such as 1,2-dichloroethane, trichloroethylene, and tetrachloroethylene into ethylene in aqueous media, which is a category of challenging reactions due to the competition of H2 evolution, can be substantially enhanced by simultaneously carrying out the reduction of CO2 on an easily prepared and cost-effective Cu metal catalyst. In the case of 1,2-dichloroethane dechlorination, a 6-fold improvement in Faradaic efficiency and a 19-fold increase in partial current density are demonstrated. Through electrochemical kinetic studies, in situ Raman spectroscopy, and computational simulations, we further find that CO2 reduction reduces hydrogen coverage on the Cu catalyst, which not only exposes more active sites for the dechlorination reaction but also enhances the effective reductive potential on the catalyst surface and reduces the kinetic barrier of the rate-determining step.

", "date": "2024-03-27", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "146", "number": "12", "publisher": "American Chemical Society", "pagerange": "8486-8491", "issn": "0002-7863", "official_url": "https://authors.library.caltech.edu/records/zfkbv-w7v86", "funders": { "items": [ { "grant_number": "CBET-2028351" }, { "grant_number": "DE-SC0021266" }, { "grant_number": "ACI-1548562" }, {} ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.3c14564", "pub_year": "2024", "author_list": "Choi, Chungseok; Kwon, Soonho; et al." }, { "id": "https://authors.library.caltech.edu/records/ahd8v-qry31", "eprint_status": "archive", "datestamp": "2024-03-26 00:06:14", "lastmod": "2024-03-26 00:06:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Ye-Jin", "name": { "family": "Kim", "given": "Ye-Jin" }, "orcid": "0000-0002-8690-8313" }, { "id": "Mendes-Jocelyn-L", "name": { "family": "Mendes", "given": "Jocelyn L." }, "orcid": "0000-0003-3850-0724" }, { "id": "Michelsen-Jonathan-M", "name": { "family": "Michelsen", "given": "Jonathan M." }, "orcid": "0000-0002-7420-5610" }, { "id": "Shin-Hyun-Jun", "name": { "family": "Shin", "given": "Hyun Jun" }, "orcid": "0000-0002-1510-2857" }, { "id": "Lee-Nara", "name": { "family": "Lee", "given": "Nara" }, "orcid": "0000-0003-2592-3031" }, { "id": "Choi-Young-Jai", "name": { "family": "Choi", "given": "Young Jai" }, "orcid": "0000-0002-1711-0607" }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott K." }, "orcid": "0000-0003-3538-2259" } ] }, "title": "Coherent charge hopping suppresses photoexcited small polarons in ErFeO\u2083 by antiadiabatic formation mechanism", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "
© 2024 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).
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Y.-J.K. is supported by the Liquid Sunlight Alliance (the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award number DE-SC0021266). J.L.M. acknowledges support by the National Science Foundation Graduate Research Fellowship Program under grant no. 1745301.

\n\n

Y.-J.K. performed the measurements with the initial technical support of J.L.M. and J.M.M. Y.-J.K. analyzed the data, carried out the ab initio calculations, and prepared figures and the Supplementary Materials. H.J.S., N.L., and Y.J.C. fabricated and characterized the specimen. S.K.C. supervised the project and provided guidance. Y.-J.K. and S.K.C. wrote the manuscript with the input from all authors.

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All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials.

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The authors declare that they have no competing interests.

", "abstract": "
Polarons are prevalent in condensed matter systems with strong electron-phonon coupling. The adiabaticity of the polaron relates to its transport properties and spatial extent. To date, only adiabatic small polaron formation has been measured following photoexcitation. The lattice reorganization energy is large enough that the first electron–optical phonon scattering event creates a small polaron without requiring substantial carrier thermalization. We measure that frustrating the iron-centered octahedra in the rare-earth orthoferrite ErFeO3 leads to antiadiabatic polaron formation. Coherent charge hopping between neighboring Fe3+\u2500Fe2+ sites is measured with transient extreme ultraviolet spectroscopy and lasts several picoseconds before the polaron forms. The resulting small polaron formation time is an order of magnitude longer than previous measurements and indicates a shallow potential well, even in the excited state. The results emphasize the importance of considering dynamic electron-electron correlations, not just electron-phonon–induced lattice changes, for small polarons for transport, catalysis, and photoexcited applications.
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", "date": "2024-03-22", "date_type": "published", "publication": "Science Advances", "volume": "10", "number": "12", "publisher": "American Association for the Advancement of Science", "pagerange": "eadk4282", "issn": "2375-2548", "official_url": "https://authors.library.caltech.edu/records/ahd8v-qry31", "funders": { "items": [ { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "BES-ERCAP0024109" }, { "grant_number": "NRF-2017R1A5A1014862" }, { "grant_number": "NRF-2021R1A2C1006375" }, { "grant_number": "NRF-2022R1A2C1006740" }, { "grant_number": "DE-SC0021266" }, { "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.adk4282", "pmcid": "PMC10954221", "primary_object": { "basename": "sciadv.adk4282.pdf", "url": "https://authors.library.caltech.edu/records/ahd8v-qry31/files/sciadv.adk4282.pdf" }, "related_objects": [ { "basename": "sciadv.adk4282_sm.pdf", "url": "https://authors.library.caltech.edu/records/ahd8v-qry31/files/sciadv.adk4282_sm.pdf" } ], "pub_year": "2024", "author_list": "Kim, Ye-Jin; Mendes, Jocelyn L.; et al." }, { "id": "https://authors.library.caltech.edu/records/h9d6j-04m72", "eprint_status": "archive", "datestamp": "2025-03-21 21:25:57", "lastmod": "2025-03-21 21:25:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Ke", "name": { "family": "Liu", "given": "Ke" }, "orcid": "0009-0004-8016-2292" }, { "id": "Wang-Yujie", "name": { "family": "Wang", "given": "Yujie" }, "orcid": "0000-0002-3729-2743" }, { "name": { "family": "Magney", "given": "Troy S." }, "orcid": "0000-0002-9033-0024" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Non-steady-state stomatal conductance modeling and its implications: from leaf to ecosystem", "ispublished": "pub", "full_text_status": "public", "note": "

© Author(s) 2024. This work is distributed under the Creative Commons Attribution 4.0 License.

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Published by Copernicus Publications on behalf of the European Geosciences Union.

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We gratefully acknowledge the support of the Explorer Grant of the Resnick Sustainability Institute at the California Institute of Technology. We would also like to thank Eliot Meeker for assisting with leaf-level gas exchange measurements.

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This research has been supported by the Explorer Grant of the Resnick Sustainability Institute at the California Institute of Technology. Troy S. Magney has been supported by the NASA ECOSTRESS Science Team Project (grant no. 80NSSC20K0078).

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CF, KL, and YW designed and conceptualized the study. TSM provided the leaf gas exchange measurements. YW developed CliMA Land and helped with the implementation of the dynamic model. KL performed the analysis. KL, CF, and YW interpreted the results. KL composed the paper with contributions from all authors.

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We coded our model and did the analysis using Julia, and the current version of the CliMA Land model with the implementation of the dynamic stomatal conductance framework is available from the project website: https://github.com/CliMA/Land. The exact version of CliMA Land used in this study and the scripts for CliMA Land simulations at the leaf and canopy scale are available on Zenodo (https://doi.org/10.5281/zenodo.10596331, Liu and Wang, 2024).

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The supplement related to this article is available online at: https://doi.org/10.5194/bg-21-1501-2024-supplement.

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This paper was edited by David Medvigy and reviewed by two anonymous referees.

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", "abstract": "

Accurate and efficient modeling of stomatal conductance (gs) has been a key challenge in vegetation models across scales. Current practice of most land surface models (LSMs) assumes steady-state gs and predicts stomatal responses to environmental cues as immediate jumps between stationary regimes. However, the response of stomata can be orders of magnitude slower than that of photosynthesis and often cannot reach a steady state before the next model time step, even on half-hourly timescales. Here, we implemented a simple dynamic gs model in the vegetation module of an LSM developed within the Climate Modeling Alliance and investigated the potential biases caused by the steady-state assumption from leaf to canopy scales. In comparison with steady-state models, the dynamic model better predicted the coupled temporal response of photosynthesis and stomatal conductance to changes in light intensity using leaf measurements. In ecosystem flux simulations, while the impact of gs hysteresis response may not be substantial in terms of monthly integrated fluxes, our results highlight the importance of considering this effect when quantifying fluxes in the mornings and evenings, as well as interpreting diurnal hysteresis patterns observed in ecosystem fluxes. Simulations also indicate that the biases in the integrated fluxes are more significant when stomata exhibit different speeds for opening and closure. Furthermore, prognostic modeling can bypass the A-Ci iterations required for steady-state simulations and can be robustly run with comparable computational costs. Overall, our study demonstrates the implications of dynamic gs modeling for improving the accuracy and efficiency of LSMs and for advancing our understanding of plant–environment interactions.

", "date": "2024-03-21", "date_type": "published", "publication": "Biogeosciences", "volume": "21", "number": "6", "publisher": "European Geosciences Union", "pagerange": "1501-1516", "issn": "1726-4189", "official_url": "https://authors.library.caltech.edu/records/h9d6j-04m72", "funders": { "items": [ { "grant_number": "Explorer Grant of Resnick Sustainability Institute" }, { "grant_number": "80NSSC20K0078" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.5194/bg-21-1501-2024", "primary_object": { "basename": "bg-21-1501-2024.pdf", "url": "https://authors.library.caltech.edu/records/h9d6j-04m72/files/bg-21-1501-2024.pdf" }, "related_objects": [ { "basename": "bg-21-1501-2024-supplement.pdf", "url": "https://authors.library.caltech.edu/records/h9d6j-04m72/files/bg-21-1501-2024-supplement.pdf" } ], "pub_year": "2024", "author_list": "Liu, Ke; Wang, Yujie; et al." }, { "id": "https://authors.library.caltech.edu/records/5be62-es895", "eprint_status": "archive", "datestamp": "2024-03-21 21:13:24", "lastmod": "2024-03-21 21:13:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Magistro-Beatrice", "name": { "family": "Magistro", "given": "Beatrice" }, "orcid": "0000-0001-7423-3577" }, { "id": "Abramson-Cecilia", "name": { "family": "Abramson", "given": "Cecilia" } }, { "id": "Ebanks-Daniel", "name": { "family": "Ebanks", "given": "Daniel" }, "orcid": "0000-0001-5928-9396" }, { "id": "Debnath-Ramit", "name": { "family": "Debnath", "given": "Ramit" }, "orcid": "0000-0003-0727-5683" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. Michael" }, "orcid": "0000-0002-8113-4451" } ] }, "title": "Identifying American climate change free riders and motivating sustainable behavior", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

© The Author(s) 2024. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

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The Resnick Sustinability Institute (RSI) at Caltech provided funding for the collection of the survey data used in this study. RSI supported the work of BM, DE and RMA. RD acknowledges the support from the Keynes Fund [JHVH], Cambridge Arts, Humanities and Social Sciences (AHSS) Grant, and the Bill & Melinda Gates Foundation [OPP1144].

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R.M.A. obtained funding for the collection of the survey data. R.M.A. and D.E. designed the survey instrument and guided implementation. B.M., C.A., and R.M.A. preprocessed the data. R.M.A., D.E., R.D., B.M. and C.A. developed the analytical approach. B.M. analyzed the data and produced the tables and graphics for the paper and S.I. All authors contributed to the drafting, writing, and editing of the paper.

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Upon publication the code and data necessary to reproduce the results reported in this paper will be made available in a permanent and public data repository, subject to any limitations imposed by human subjects considerations. Replication materials can be accessed here: https://drive.google.com/drive/folders/1oAOnYajSWRkA_WU5fQAOU8SXmD-6z9be.

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The authors declare no competing interests.

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", "abstract": "
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Free riders, who benefit from collective efforts to mitigate climate change but do not actively contribute, play a key role in shaping behavioral climate action. Using a sample of 2096 registered American voters, we explore the discrepancy between two groups of free riders: cynics, who recognize the significance of environmental issues but do not adopt sustainable behaviors, and doubters, who neither recognize the significance nor engage in such actions. Through statistical analyses, we show these two groups are different. Doubters are predominantly male, younger, with lower income and education, exhibit stronger conspiracy beliefs, lower altruism, and limited environmental knowledge, are more likely to have voted for Trump and lean towards conservative ideology. Cynics are younger, religious, higher in socioeconomic status, environmentally informed, liberal-leaning, and less likely to support Trump. Our research provides insights on who could be most effectively persuaded to make climate-sensitive lifestyle changes and provides recommendations to prompt involvement in individual sustainability behaviors. Our findings suggest that for doubters, incentivizing sustainability through positive incentives, such as financial rewards, may be particularly effective. Conversely, for cynics, we argue that engaging them in more community-driven and social influence initiatives could effectively translate their passive beliefs into active participation.

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", "date": "2024-03-19", "date_type": "published", "publication": "Scientific Reports", "volume": "14", "publisher": "Nature", "pagerange": "6575", "issn": "2045-2322", "official_url": "https://authors.library.caltech.edu/records/5be62-es895", "funders": { "items": [ {}, {}, { "grant_number": "OPP1144" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41598-024-57042-w", "pmcid": "PMC10951196", "primary_object": { "basename": "41598_2024_57042_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/5be62-es895/files/41598_2024_57042_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41598-024-57042-w.pdf", "url": "https://authors.library.caltech.edu/records/5be62-es895/files/s41598-024-57042-w.pdf" } ], "pub_year": "2024", "author_list": "Magistro, Beatrice; Abramson, Cecilia; et al." }, { "id": "https://authors.library.caltech.edu/records/9s381-baa23", "eprint_status": "archive", "datestamp": "2024-03-15 16:28:13", "lastmod": "2024-03-15 16:28:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "An emergent constraint on the thermal sensitivity of photosynthesis and greenness in the high latitude northern forests", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

© The Author(s) 2024. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

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We thank James Randerson, Dave Schimel, and TRENDY modelers (Stephen Sitch, Pierre Friedlingstein, Vivek Arora, Atul Jain, Markus Kautz, Danica Lobardozzi, Sebastia Lienert, Julia Nabel, Benjamin Poulter, Nicolas Vuichard, Andy Wiltshire, and Ning Zeng) for their comments and suggestions in preparing this paper. We also thank Dr. Ranga Myneni and Dr. Martin Jung for providing the GIMMS and FLUXCOM data. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advance Supercomputing (NAS) division at Ames Research Center.

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Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration, (80NM0018D0004). P.W. acknowledge the support from Caltech’s Resnick Sustainability Institute.

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Conceptualization and methodology: J.L.; Investigation: J.L. and P.O.W.; Visualization: J.L.; Writing—original draft: J.L. and P.O.W.

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All data used to support the findings of this study are publicly available. TRENDY model simulations and its met drivers are available on request from TRENDY coordinator Dr. S. Sitch (s.a.sitch@exeter.ac.uk). The GIMMS AVHRR and MODIS LAI data are available upon request from by Dr. Ranga Myneni (rmyneni@bu.edu). The NOAA AVHRR LAI data is available at: https://www.ncei.noaa.gov/access/metadata/landing-page/bin/iso?id=gov.noaa.ncdc:C01559. The MCD-MODIS is available at: https://lpdaac.usgs.gov/products/mcd15a2hv006/. The FLUXCOM GPP dataset was obtained from https://www.bgc-jena.mpg.de/geodb/projects/Data.php. The OCO-2 SIF data is publicly available at https://disc.gsfc.nasa.gov/datasets/OCO2_L2_Lite_SIF_10r/summary?keywords=oco2%20sif%20lite The CERES data is available at https://asdc.larc.nasa.gov/project/CERES.

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The authors declare no competing interests.

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", "abstract": "
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Despite the general consensus that the warming over the high latitudes northern forests (HLNF) has led to enhanced photosynthetic activity and contributed to the greening trend, isolating the impact of temperature increase on photosynthesis and greenness has been difficult due to the concurring influence of the CO2 fertilization effect. Here, using an ensemble of simulations from biogeochemical models that have contributed to the Trends in Net Land Atmosphere Carbon Exchange project (TRENDY), we identify an emergent relationship between the simulation of the climate-driven temporal changes in both gross primary productivity (GPP) and greenness (Leaf Area Index, LAI) and the model’s spatial sensitivity of these quantities to growing-season (GS) temperature. Combined with spatially-resolved observations of LAI and GPP, we estimate that GS-LAI and GS-GPP increase by 17.0 ± 2.4% and 24.0 ± 3.0% per degree of warming, respectively. The observationally-derived sensitivities of LAI and GPP to temperature are about 40% and 71% higher, respectively, than the mean of the ensemble of simulations from TRENDY, primarily due to the model underestimation of the sensitivity of light use efficiency to temperature. We estimate that the regional mean GS-GPP increased 28.2 ± 5.1% between 1983–1986 and 2013–2016, much larger than the 5.8 ± 1.4% increase from the CO2 fertilization effect implied by Wenzel et al. This suggests that warming, not CO2 fertilization, is primarily responsible for the observed dramatic changes in the HLNF biosphere over the last century.

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", "date": "2024-03-14", "date_type": "published", "publication": "Scientific Reports", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "6189", "issn": "2045-2322", "official_url": "https://authors.library.caltech.edu/records/9s381-baa23", "funders": { "items": [ { "grant_number": "80NM0018D0004" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41598-024-56362-1", "primary_object": { "basename": "s41598-024-56362-1.pdf", "url": "https://authors.library.caltech.edu/records/9s381-baa23/files/s41598-024-56362-1.pdf" }, "related_objects": [ { "basename": "41598_2024_56362_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/9s381-baa23/files/41598_2024_56362_MOESM1_ESM.pdf" } ], "pub_year": "2024", "author_list": "Liu, Junjie and Wennberg, Paul O." }, { "id": "https://authors.library.caltech.edu/records/psdcb-s0478", "eprint_status": "archive", "datestamp": "2024-03-12 17:29:32", "lastmod": "2024-03-12 17:29:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chang-Wesley", "name": { "family": "Chang", "given": "Wesley" }, "orcid": "0000-0002-9389-1265" }, { "id": "Jain-Anukta", "name": { "family": "Jain", "given": "Anukta" }, "orcid": "0009-0005-7103-4050" }, { "id": "Rezaie-Fateme", "name": { "family": "Rezaie", "given": "Fateme" } }, { "id": "Manthiram-Karthish", "name": { "family": "Manthiram", "given": "Karthish" }, "orcid": "0000-0001-9260-3391" } ] }, "title": "Lithium-mediated nitrogen reduction to ammonia via the catalytic solid\u2013electrolyte interphase", "ispublished": "pub", "full_text_status": "public", "keywords": "Process Chemistry and Technology; Biochemistry; Bioengineering; Catalysis", "note": "

© Springer Nature Limited 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

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This material is based on work supported by the National Science Foundation (grant no. 2204756). We gratefully acknowledge support from the Resnick Sustainability Institute. K.M. gratefully acknowledges support from the Sloan Foundation. W.C. acknowledges funding support from the Arnold and Mabel Beckman Foundation via a 2022 Arnold O. Beckman Postdoctoral Fellowship in Chemical Sciences. F.R. acknowledges funding support from the Independent Research Fund Denmark (DFF), case no. 0217-00234B. We also thank M. Yusov, C. Klein and G. Lee for productive and helpful feedback and discussions.

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These authors contributed equally: Wesley Chang, Anukta Jain.

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W.C. conducted the initial meta-analysis from literature sources, analysed the data and generated the figures. A.J. brought the manuscript to submission-ready completion with detailed edits. W.C. and A.J. led the majority of the work, with input from the whole group. F.R. helped decide our cell-naming convention. K.M. mentored, edited and financed the work. All authors contributed to manuscript proofreading.

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The authors declare no competing interests.

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", "abstract": "

The lithium-mediated nitrogen reduction reaction (LiNRR) produces ammonia in ambient conditions. This electrochemical pathway is dependent on a catalytic solid–electrolyte interphase—a nanoscale passivation layer formed from reductive electrolyte decomposition on the surface of lithium metal. The catalytic solid–electrolyte interphase is a unique nanostructured environment that exists on reactive metal surfaces and intimately influences product selectivity. Here we explore recent progress made in the field of lithium-mediated nitrogen reduction to ammonia, especially in light of growing knowledge about the nature of the catalytic solid–electrolyte interphase. We systematically analyse the observed chemical species and reactions that occur within the solid–electrolyte interphase. We also summarize key developments in kinetic and transport models, as well as highlight the cathodic and complementary anodic reactions. Trends in ammonia selectivities and rates with varying electrolyte compositions, cell designs and operating conditions are extracted and used to articulate a path forward for continued development of lithium-mediated nitrogen reduction to ammonia.

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", "date": "2024-03-11", "date_type": "published", "publication": "Nature Catalysis", "publisher": "Nature Publishing Group", "issn": "2520-1158", "official_url": "https://authors.library.caltech.edu/records/psdcb-s0478", "funders": { "items": [ { "grant_number": "CBET-2204756" }, {}, {}, {}, { "grant_number": "0217-00234B" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41929-024-01115-6", "pub_year": "2024", "author_list": "Chang, Wesley; Jain, Anukta; et al." }, { "id": "https://authors.library.caltech.edu/records/kkw9a-6qg42", "eprint_status": "archive", "datestamp": "2024-04-10 16:07:49", "lastmod": "2024-06-05 19:45:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "B\u00edm-Daniel", "name": { "family": "B\u00edm", "given": "Daniel" }, "orcid": "0000-0003-3100-4293" }, { "id": "Luedecke-Kaitlin-M", "name": { "family": "Luedecke", "given": "Kaitlin M." }, "orcid": "0000-0002-8163-9417" }, { "id": "Cagan-David-A", "name": { "family": "Cagan", "given": "David A." }, "orcid": "0000-0002-4719-2789" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Light Activation and Photophysics of a Structurally Constrained Nickel(II)\u2013Bipyridine Aryl Halide Complex", "ispublished": "pub", "full_text_status": "public", "keywords": "Inorganic Chemistry; Physical and Theoretical Chemistry", "note": "

© 2024 American Chemical Society.

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We acknowledge Dr. Erica Sutcliffe and Nathanael P. Kazmierczak for helpful discussions. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 883987 (D.B.). K.M.L. and D.A.C. acknowledge support from the National Science Foundation Graduate Research Fellowship (NSF GRFP) under grant no. DGE-1745301. Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R35-GM142595). The computations presented here were in part conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology and in part by the IT4Innovations National Supercomputing Center under the programme of the Ministry of Education, Youth and Sports of the Czech Republic through the e-INFRA CZ (ID:90254).

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D.B.: conceptualization; methodology; investigation; formal analysis; writing\u2500original draft; writing\u2500review and editing. K.M.L.: methodology; investigation; formal analysis; writing\u2500original draft; writing\u2500review and editing. D.A.C.: methodology; writing\u2500review and editing. R.G.H.: conceptualization; methodology; writing\u2500original draft; writing\u2500review and editing; supervision; project administration; funding acquisition.

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The authors declare no competing financial interest.

\n\n", "abstract": "
\n

Transition-metal photoredox catalysis has transformed organic synthesis by harnessing light to construct complex molecules. Nickel(II)–bipyridine (bpy) aryl halide complexes are a significant class of cross-coupling catalysts that can be activated via direct light excitation. This study investigates the effects of molecular structure on the photophysics of these catalysts by considering an underexplored, structurally constrained Ni(II)–bpy aryl halide complex in which the aryl and bpy ligands are covalently tethered alongside traditional unconstrained complexes. Intriguingly, the tethered complex is photochemically stable but features a reversible Ni(II)–C(aryl) \u21c4 [Ni(I)···C(aryl)•] equilibrium upon direct photoexcitation. When an electrophile is introduced during photoirradiation, we demonstrate a preference for photodissociation over recombination, rendering the parent Ni(II) complex a stable source of a reactive Ni(I) intermediate. Here, we characterize the reversible photochemical behavior of the tethered complex by kinetic analyses, quantum chemical calculations, and ultrafast transient absorption spectroscopy. Comparison to the previously characterized Ni(II)–bpy aryl halide complex indicates that the structural constraints considered here dramatically influence the excited state relaxation pathway and provide insight into the characteristics of excited-state Ni(II)–C bond homolysis and aryl radical reassociation dynamics. This study enriches the understanding of molecular structure effects in photoredox catalysis and offers new possibilities for designing customized photoactive catalysts for precise organic synthesis.

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", "date": "2024-03-04", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "63", "number": "9", "publisher": "American Chemical Society", "pagerange": "4120-4131", "issn": "0020-1669", "official_url": "https://authors.library.caltech.edu/records/kkw9a-6qg42", "funders": { "items": [ { "grant_number": "883987" }, { "grant_number": "DGE-1745301" }, { "grant_number": "R35-GM142595" }, { "grant_number": "90254" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.3c03822", "pmcid": "PMC11000520", "primary_object": { "basename": "nihms-1980001.pdf", "url": "https://authors.library.caltech.edu/records/kkw9a-6qg42/files/nihms-1980001.pdf" }, "related_objects": [ { "basename": "ic3c03822_si_001.pdf", "url": "https://authors.library.caltech.edu/records/kkw9a-6qg42/files/ic3c03822_si_001.pdf" } ], "pub_year": "2024", "author_list": "B\u00edm, Daniel; Luedecke, Kaitlin M.; et al." }, { "id": "https://authors.library.caltech.edu/records/ccsj6-vw930", "eprint_status": "archive", "datestamp": "2024-12-04 20:10:56", "lastmod": "2025-02-12 00:16:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Jakes", "given": "Maya I." }, "orcid": "0000-0003-0658-6615" }, { "name": { "family": "Phillips", "given": "Helen E." }, "orcid": "0000-0002-2941-7577" }, { "name": { "family": "Foppert", "given": "Annie" }, "orcid": "0000-0003-2958-1454" }, { "name": { "family": "Cyriac", "given": "Ajitha" }, "orcid": "0000-0001-6149-740X" }, { "name": { "family": "Bindoff", "given": "Nathaniel L." }, "orcid": "0000-0001-5662-9519" }, { "name": { "family": "Rintoul", "given": "Stephen R." }, "orcid": "0000-0002-7055-9876" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" } ] }, "title": "Observational Evidence of Cold Filamentary Intensification in an Energetic Meander of the Antarctic Circumpolar Current", "ispublished": "pub", "full_text_status": "public", "keywords": "Frontogenesis/frontolysis; Ocean dynamics; Small scale processes; Vertical motion; In situ oceanic observations; Satellite observations", "note": "

Open access. © 2024 American Meteorological Society. This published article is licensed under the terms of the default AMS reuse license.

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We thank the R/V Investigator officers and crew, CSIRO Marine National Facility technical team and scientists who contributed to the collection of the data on the IN2018_V05 voyage. Their efforts enabled a comprehensive finescale survey of an Antarctic Circumpolar Current meander in the presence of significant winds and waves. We acknowledge support from the Australian Government as part of the Antarctic Science Collaboration Initiative, the Australian Research Council’s Discovery Projects (DP170102162) and Special Research Initiative, Australian Centre for Excellence in Antarctic Science (SR200100008) and from the Australian Government under the National Environmental Science Program (Climate Systems). Our team has benefited enormously from the Graduate Program of the Australian Research Council Centre of Excellence for Climate Extremes (CE170100023). AFT was supported by the Resnick Sustainability Institute and the Ginkgo Foundation. MIJ thanks Helen Phillips for writing the original routine EM-APEX quality control MATLAB scripts, and Ajitha Cyriac and Jan Jaap Meijer for adapting and documenting the scripts. We are grateful for the detailed and constructive comments from three anonymous reviewers that have helped improve the paper.

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The EM-APEX float data and quality control toolbox is publicly available at the Australian Antarctic Data Centre (data.aad.gov.au/metadata/EMAPEX_Macquarie_2018). Triaxus and ADCP data from the voyage are publicly available for download from the MNF website (marine.csiro.au/data/trawler/survey_details.cfm?survey=IN2018_V05). Daily L3-gridded (0.02°) SST data used in this study can be downloaded via the IMOS data portal (researchdata.edu.au/imos-srs-sst-time-australia/1370442?source=suggested_datasets). Daily L4-gridded (0.25°) SSH and derived geostrophic velocities can be obtained from the Copernicus website (data.marine.copernicus.eu/product/SEALEVEL_GLO_PHY_L4_MY_008_047/). FSLEs (0.04° grid resolution) computed from Copernicus L4-gridded geostrophic velocities can be downloaded from Aviso+ (aviso.altimetry.fr/en/data/products/value-added-products/fsle-finite-size-lyapunov-exponents). Python implementation of the TEOS-10 Gibbs Sea-Water (GSW) Oceanographic Toolbox is available at github.com/TEOS-10/GSW-Python. Python scripts for this analysis will be made publicly available at github.com/mayajakes/phd-public.

", "abstract": "

Eddy stirring at mesoscale oceanic fronts generates finescale filaments, visible in submesoscale-resolving model simulations and high-resolution satellite images of sea surface temperature, ocean color, and sea ice. Submesoscale filaments have widths of O(1–10) km and evolve on time scales of hours to days, making them extremely challenging to observe. Despite their relatively small scale, submesoscale processes play a key role in the climate system by providing a route to dissipation; altering the stratification of the ocean interior; and generating strong vertical velocities that exchange heat, carbon, nutrients, and oxygen between the mixed layer and the ocean interior. We present a unique set of in situ and satellite observations in a standing meander region of the Antarctic Circumpolar Current (ACC) that supports the theory of cold filamentary intensification—revealing enhanced vertical velocities and evidence of subduction and ventilation associated with finescale cold filaments. We show that these processes are not confined to the mixed layer; EM-APEX floats reveal enhanced downward velocities (>100 m day−1) and evidence of ageostrophic motion extending as deep as 1600 dbar, associated with a ∼20-km-wide cold filament. A finer-scale (∼5 km wide) cold filament crossed by a towed Triaxus is associated with anomalous chlorophyll and oxygen values extending at least 100–200 dbar below the base of the mixed layer, implying recent subduction and ventilation. Energetic standing meanders within the weakly stratified ACC provide an environment conductive to the generation of finescale filaments that can transport water mass properties across mesoscale fronts and deep into the ocean interior.

", "date": "2024-03", "date_type": "published", "publication": "Journal of Physical Oceanography", "volume": "54", "number": "3", "publisher": "American Meteorological Society", "pagerange": "717-740", "issn": "0022-3670", "official_url": "https://authors.library.caltech.edu/records/ccsj6-vw930", "funders": { "items": [ { "grant_number": "DP170102162" }, {}, { "agency": "Ginkgo Foundation" }, { "agency": "Australian Centre for Excellence in Antarctic Science", "grant_number": "SR200100008" }, { "agency": "Australian Government''s Antarctic Science Collaboration Initiative", "grant_number": "ASCI000002" }, { "agency": "Australian Government''s National Environmental Science Program" }, { "agency": "ARC Australian Research Council Centre of Excellence for Climate Extremes", "grant_number": "CE170100023" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1175/jpo-d-23-0085.1", "primary_object": { "basename": "phoc-JPO-D-23-0085.1.pdf", "url": "https://authors.library.caltech.edu/records/ccsj6-vw930/files/phoc-JPO-D-23-0085.1.pdf" }, "pub_year": "2024", "author_list": "Jakes, Maya I.; Phillips, Helen E.; et al." }, { "id": "https://authors.library.caltech.edu/records/shb5c-x8121", "eprint_status": "archive", "datestamp": "2024-03-05 17:58:28", "lastmod": "2024-03-05 17:58:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johansen-Christian-M", "name": { "family": "Johansen", "given": "Christian M." }, "orcid": "0000-0003-0066-4424" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Catalytic Reduction of Cyanide to Ammonia and Methane at a Mononuclear Fe Site", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

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We acknowledge support from NIH (GM-075757). We thank the Dow Next Generation Educator Fund and Instrumentation Grants for their support of the NMR facility at Caltech. We also thank the Resnick Sustainability Institute at Caltech for support of enabling facilities and instrumentation, including the RSI Water and Environment Lab (WEL). This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 using NERSC award NERSC DDR-ERCAP0026667. C.M.J. is grateful for support from the Aker Scholarship foundation. We thank Dr. Nathan Dalleska and Dr. Nicholas Watkins for assistance with GC experiments and Dr. Sayan Bannerjee for assistance with computational studies.

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This study was funded by the National Institutes of Health (R01 GM-075757).

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The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.

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The authors declare no competing financial interest.

\n\n", "abstract": "
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Nitrogenase enzymes catalyze nitrogen reduction (N2R) to ammonia and also the reduction of non-native substrates, including the 7H+/6e– reduction of cyanide to CH4 and NH3. CN– and N2 are isoelectronic, and it is hence fascinating to compare the mechanisms of synthetic Fe catalysts capable of both CN– and N2 reduction. Here, we describe the catalytic reduction of CN– to NH3 and CH4 by a highly selective (P3Si)Fe(CN) catalyst (P3Si represents a tris(phosphine)silyl ligand). Catalysis is driven in the presence of excess acid ([Ph2NH2]OTf) and reductant ((C6H6)2Cr), with turnover as high as 73 demonstrated. This catalyst system is also modestly competent for N2R and structurally related to other tris(phosphine)Fe-based N2R catalysts. The choice of catalyst and reductant is important to observe high yields. Mechanistic studies elucidate several intermediates of CN– reduction, including iron isocyanides (P3SiFeCNH+/0) and terminal iron aminocarbynes (P3SiFeCNH2+/0). Aminocarbynes are isoelectronic to iron hydrazidos (Fe=N–NH2+/0), which have been invoked as selectivity-determining intermediates of N2R (NH3 versus N2H4 products). For the present CN– reduction catalysis, reduction of aminocarbyne P3SiFeCNH2+ is proposed to be rate but not selectivity contributing. Instead, by comparison with the reactivity of a methylated aminocarbyne analogue (P3SiFeCNMe2), and associated computational studies, formation of a Fischer carbene (P3SiFeC(H)(NH2)+) intermediate that is on path for either CH4 and NH3 (6 e–) or CH3NH2 (4 e–) products is proposed. From this carbene intermediate, pathways to the observed CH4 and NH3 products (distinct from CH3NH2 formation) are considered to compare and contrast the (likely) mechanism/s of CN– and N2 reduction.

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", "date": "2024-02-28", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "146", "number": "8", "publisher": "American Chemical Society", "pagerange": "5343-5354", "issn": "0002-7863", "official_url": "https://authors.library.caltech.edu/records/shb5c-x8121", "funders": { "items": [ { "grant_number": "R01 GM-075757" }, {}, {}, { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "DDR-ERCAP0026667" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.3c12395", "pmcid": "PMC10910527", "primary_object": { "basename": "ja3c12395.pdf", "url": "https://authors.library.caltech.edu/records/shb5c-x8121/files/ja3c12395.pdf" }, "related_objects": [ { "basename": "ja3c12395_si_002.pdf", "url": "https://authors.library.caltech.edu/records/shb5c-x8121/files/ja3c12395_si_002.pdf" }, { "basename": "ja3c12395_si_001.txt", "url": "https://authors.library.caltech.edu/records/shb5c-x8121/files/ja3c12395_si_001.txt" } ], "pub_year": "2024", "author_list": "Johansen, Christian M. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/06m4r-8jf10", "eprint_status": "archive", "datestamp": "2024-04-19 21:56:29", "lastmod": "2024-04-19 21:56:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Zongyi", "name": { "family": "Li", "given": "Zongyi" }, "orcid": "0000-0003-2081-9665" }, { "id": "Zheng-Hongkai", "name": { "family": "Zheng", "given": "Hongkai" } }, { "id": "Kovachki-Nikola", "name": { "family": "Kovachki", "given": "Nikola" }, "orcid": "0000-0002-3650-2972" }, { "id": "Jin-David", "name": { "family": "Jin", "given": "David" } }, { "id": "Chen-Haoxuan", "name": { "family": "Chen", "given": "Haoxuan" }, "orcid": "0000-0002-8238-2764" }, { "id": "Liu-Burigede", "name": { "family": "Liu", "given": "Burigede" }, "orcid": "0000-0002-6518-3368" }, { "id": "Azizzadenesheli-Kamyar", "name": { "family": "Azizzadenesheli", "given": "Kamyar" }, "orcid": "0000-0001-8507-1868" }, { "id": "Anandkumar-A", "name": { "family": "Anandkumar", "given": "Anima" }, "orcid": "0000-0002-6974-6797" } ] }, "title": "Physics-Informed Neural Operator for Learning Partial Differential Equations", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 Copyright held by the owner/author(s). Publication rights licensed to ACM.

\n\n

The authors want to thank Sifan Wang for meaningful discussions.

\n


Z. Li gratefully acknowledges the inancial support from the Kortschak Scholars, PIMCO Fellows, and Amazon AI4Science Fellows programs. N. Kovachki was partially supported by the Amazon AI4Science Fellowship. A. Anandkumar is supported in part by the Bren endowed chair professorship.

\n


This work was carried out on (1) the NVIDIA NGC as part of Zongyi Li’s internship and (2) the Resnick High-Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.

", "abstract": "
\n
\n
\n
\n

In this paper, we propose physics-informed neural operators (PINO) that combine training data and physics constraints to learn the solution operator of a given family of parametric Partial Differential Equations (PDE). PINO is the first hybrid approach incorporating data and PDE constraints at different resolutions to learn the operator. Specifically, in PINO, we combine coarse-resolution training data with PDE constraints imposed at a higher resolution. The resulting PINO model can accurately approximate the ground-truth solution operator for many popular PDE families and shows no degradation in accuracy even under zero-shot super-resolution, i.e., being able to predict beyond the resolution of training data. PINO uses the Fourier neural operator (FNO) framework that is guaranteed to be a universal approximator for any continuous operator and discretization convergent in the limit of mesh refinement. By adding PDE constraints to FNO at a higher resolution, we obtain a high-fidelity reconstruction of the ground-truth operator. Moreover, PINO succeeds in settings where no training data is available and only PDE constraints are imposed, while previous approaches, such as the Physics-Informed Neural Network (PINN), fail due to optimization challenges, e.g., in multi-scale dynamic systems such as Kolmogorov flows.

\n
\n
\n
\n
", "date": "2024-02-21", "date_type": "published", "publication": "ACM / IMS Journal of Data Science", "publisher": "Association for Computing Machinery", "issn": "2831-3194", "official_url": "https://authors.library.caltech.edu/records/06m4r-8jf10", "funders": { "items": [ { "grant_number": "Kortschak Scholars" }, { "grant_number": "Amazon AI4Science Fellowship" }, { "grant_number": "Bren Professor of Computing and Mathematical Sciences" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1145/3648506", "primary_object": { "basename": "3648506.pdf", "url": "https://authors.library.caltech.edu/records/06m4r-8jf10/files/3648506.pdf" }, "pub_year": "2024", "author_list": "Li, Zongyi; Zheng, Hongkai; et al." }, { "id": "https://authors.library.caltech.edu/records/5tqf9-jve59", "eprint_status": "archive", "datestamp": "2024-02-22 17:02:35", "lastmod": "2024-02-22 17:02:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulte-Samuel-J", "name": { "family": "Schulte", "given": "Samuel J." }, "orcid": "0000-0001-9982-6504" }, { "id": "Shin-Boyoung", "name": { "family": "Shin", "given": "Boyoung" }, "orcid": "0000-0001-7926-5527" }, { "id": "Rothenberg-E-V", "name": { "family": "Rothenberg", "given": "Ellen V." }, "orcid": "0000-0002-3901-347X" }, { "id": "Pierce-N-A", "name": { "family": "Pierce", "given": "Niles A." }, "orcid": "0000-0003-2367-4406" } ] }, "title": "Multiplex, Quantitative, High-Resolution Imaging of Protein:Protein Complexes via Hybridization Chain Reaction", "ispublished": "pub", "full_text_status": "public", "keywords": "Molecular Medicine; General Medicine; Biochemistry", "note": "

© 2024 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.

\n\n
\n

We thank M. E. Bronner for reading a draft of the manuscript and G. Shin of the Molecular Technologies resource within the Beckman Institute at Caltech for providing HCR reagents. This work was funded by the National Institutes of Health (NIBIB R01EB006192 and NIGMS training grant GM008042 to S.J.S.) and by the Beckman Institute at Caltech (Programmable Molecular Technology Center, PMTC). The Leica Stellaris 8 confocal microscope in the Biological Imaging Facility within the Beckman Institute at Caltech was purchased with support from Caltech and the following Caltech entities: the Beckman Institute, the Resnick Sustainability Institute, the Division of Biology and Biological Engineering, and the Merkin Institute for Translational Research.

\n
\n\n

The authors declare the following competing financial interest(s): Patents, pending patent applications, and the startup company Molecular Instruments.

", "abstract": "
\n

Signal amplification based on the mechanism of hybridization chain reaction (HCR) facilitates spatial exploration of gene regulatory networks by enabling multiplex, quantitative, high-resolution imaging of RNA and protein targets. Here, we extend these capabilities to the imaging of protein:protein complexes, using proximity-dependent cooperative probes to conditionally generate a single amplified signal if and only if two target proteins are colocalized within the sample. HCR probes and amplifiers combine to provide automatic background suppression throughout the protocol, ensuring that even if reagents bind nonspecifically in the sample, they will not generate amplified background. We demonstrate protein:protein imaging with a high signal-to-background ratio in human cells, mouse proT cells, and highly autofluorescent formalin-fixed paraffin-embedded (FFPE) human breast tissue sections. Further, we demonstrate multiplex imaging of three different protein:protein complexes simultaneously and validate that HCR enables accurate and precise relative quantitation of protein:protein complexes with subcellular resolution in an anatomical context. Moreover, we establish a unified framework for simultaneous multiplex, quantitative, high-resolution imaging of RNA, protein, and protein:protein targets, with one-step, isothermal, enzyme-free HCR signal amplification performed for all target classes simultaneously.

\n
", "date": "2024-02-16", "date_type": "published", "publication": "ACS Chemical Biology", "volume": "19", "number": "2", "publisher": "American Chemical Society", "pagerange": "280-288", "issn": "1554-8929", "official_url": "https://authors.library.caltech.edu/records/5tqf9-jve59", "funders": { "items": [ { "grant_number": "R01EB006192" }, { "grant_number": "GM008042" }, { "agency": "Beckman Institute, California Institute of Technology" } ] }, "local_group": { "items": [ { "id": "Division-of-Biology-and-Biological-Engineering" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Richard-Merkin-Institute" } ] }, "doi": "10.1021/acschembio.3c00431", "pmcid": "PMC10877569", "primary_object": { "basename": "cb3c00431.pdf", "url": "https://authors.library.caltech.edu/records/5tqf9-jve59/files/cb3c00431.pdf" }, "related_objects": [ { "basename": "schulte-et-al-2024-multiplex-quantitative-high-resolution-imaging-of-protein-protein-complexes-via-hybridization-chain.pdf", "url": "https://authors.library.caltech.edu/records/5tqf9-jve59/files/schulte-et-al-2024-multiplex-quantitative-high-resolution-imaging-of-protein-protein-complexes-via-hybridization-chain.pdf" } ], "pub_year": "2024", "author_list": "Schulte, Samuel J.; Shin, Boyoung; et al." }, { "id": "https://authors.library.caltech.edu/records/h03b9-38d60", "eprint_status": "archive", "datestamp": "2024-02-07 22:57:41", "lastmod": "2025-11-12 23:34:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xuan-Jerry-W", "name": { "family": "Xuan", "given": "Jerry W." }, "orcid": "0000-0002-6618-1137" }, { "name": { "family": "Wang", "given": "Jason" }, "orcid": "0000-0003-0774-6502" }, { "name": { "family": "Finnerty", "given": "Luke" }, "orcid": "0000-0002-1392-0768" }, { "id": "Horstman-Katelyn", "name": { "family": "Horstman", "given": "Katelyn" }, "orcid": "0000-0001-9708-8667" }, { "name": { "family": "Grimm", "given": "Simon" } }, { "name": { "family": "Peck", "given": "Anne E." }, "orcid": "0000-0003-2461-6881" }, { "name": { "family": "Nielsen", "given": "Eric" }, "orcid": "0000-0001-6975-9056" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather A." }, "orcid": "0000-0002-5375-4725" }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "name": { "family": "Isaacson", "given": "Howard" }, "orcid": "0000-0002-0531-1073" }, { "id": "Howard-A-W", "name": { "family": "Howard", "given": "Andrew W." }, "orcid": "0000-0001-8638-0320" }, { "name": { "family": "Liu", "given": "Michael C." }, "orcid": "0000-0003-2232-7664" }, { "name": { "family": "Walker", "given": "Sam" }, "orcid": "0000-0001-7062-815X" }, { "name": { "family": "Phillips", "given": "Mark W." } }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Ruffio-J-B", "name": { "family": "Ruffio", "given": "Jean-Baptiste" }, "orcid": "0000-0003-2233-4821" }, { "id": "Zhang-Yapeng", "name": { "family": "Zhang", "given": "Yapeng" }, "orcid": "0000-0003-0097-4414" }, { "id": "Inglis-Julie", "name": { "family": "Inglis", "given": "Julie" }, "orcid": "0000-0001-9164-7966" }, { "id": "Wallack-N-L", "name": { "family": "Wallack", "given": "Nicole L." }, "orcid": "0000-0003-0354-0187" }, { "id": "Sanghi-Aniket", "name": { "family": "Sanghi", "given": "Aniket" }, "orcid": "0000-0002-1838-4757" }, { "name": { "family": "Gonzales", "given": "Erica J." }, "orcid": "0000-0002-9329-2190" }, { "id": "Dai-Fei", "name": { "family": "Dai", "given": "Fei" }, "orcid": "0000-0002-8958-0683" }, { "id": "Baker-Ashley", "name": { "family": "Baker", "given": "Ashley" }, "orcid": "0000-0002-6525-7013" }, { "id": "Bartos-Randall", "name": { "family": "Bartos", "given": "Randall" } }, { "name": { "family": "Bond", "given": "Charlotte Z." } }, { "name": { "family": "Bryan", "given": "Marta L." }, "orcid": "0000-0002-6076-5967" }, { "id": "Calvin-Benjamin", "name": { "family": "Calvin", "given": "Benjamin" }, "orcid": "0000-0003-4737-5486" }, { "name": { "family": "Cetre", "given": "Sylvain" } }, { "name": { "family": "Delorme", "given": "Jacques-Robert" }, "orcid": "0000-0001-8953-1008" }, { "name": { "family": "Doppmann", "given": "Greg" } }, { "id": "Echeverri-Daniel", "name": { "family": "Echeverri", "given": "Daniel" }, "orcid": "0000-0002-1583-2040" }, { "name": { "family": "Fitzgerald", "given": "Michael P." }, "orcid": "0000-0002-0176-8973" }, { "id": "Jovanovic-N", "name": { "family": "Jovanovic", "given": "Nemanja" }, "orcid": "0000-0001-5213-6207" }, { "id": "Liberman-Joshua", "name": { "family": "Liberman", "given": "Joshua" }, "orcid": "0000-0002-4934-3042" }, { "name": { "family": "L\u00f3pez", "given": "Ronald A." }, "orcid": "0000-0002-2019-4995" }, { "name": { "family": "Martin", "given": "Emily C." }, "orcid": "0000-0002-0618-5128" }, { "name": { "family": "Morris", "given": "Evan" } }, { "id": "Pezzato-Jacklyn", "name": { "family": "Pezzato", "given": "Jacklyn" } }, { "id": "Ruane-G-J", "name": { "family": "Ruane", "given": "Garreth" }, "orcid": "0000-0003-4769-1665" }, { "name": { "family": "Sappey", "given": "Ben" }, "orcid": "0000-0003-1399-3593" }, { "id": "Schofield-Tobias", "name": { "family": "Schofield", "given": "Tobias" } }, { "name": { "family": "Skemer", "given": "Andrew" }, "orcid": "0000-0001-6098-3924" }, { "name": { "family": "Venenciano", "given": "Taylor" }, "orcid": "0000-0003-0122-8915" }, { "id": "Wallace-J-Kent", "name": { "family": "Wallace", "given": "J. Kent" }, "orcid": "0000-0001-5299-6899" }, { "name": { "family": "Wang", "given": "Ji" }, "orcid": "0000-0002-4361-8885" }, { "name": { "family": "Wizinowich", "given": "Peter" }, "orcid": "0000-0002-1646-442X" }, { "id": "Xin-Yinzi", "name": { "family": "Xin", "given": "Yinzi" }, "orcid": "0000-0002-6171-9081" }, { "name": { "family": "Agrawal", "given": "Shubh" }, "orcid": "0000-0003-2429-5811" }, { "name": { "family": "Do \u00d3", "given": "Clarissa R." }, "orcid": "0000-0001-5173-2947" }, { "name": { "family": "Hsu", "given": "Chih-Chun" }, "orcid": "0000-0002-5370-7494" }, { "name": { "family": "Phillips", "given": "Caprice L." }, "orcid": "0000-0001-5610-5328" } ] }, "title": "Validation of Elemental and Isotopic Abundances in Late-M Spectral Types with the Benchmark HIP 55507 AB System", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "

© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

\n\n

J.X. thanks Paul Mollière for help with generating new opacities in petitRADTRANS and using easyCHEM. J.X. is supported by the NASA Future Investigators in NASA Earth and Space Science and Technology (FINESST) award No. 80NSSC23K1434. J.X. also acknowledges support from the Keck Visiting Scholars Program (KVSP) to commission KPIC Phase II capabilities. D.E. is supported by NASA FINESST award No. 80NSSC19K1423. D.E. also acknowledges support from the Keck Visiting Scholars Program (KVSP) to install the Phase II upgrades. Funding for KPIC has been provided by the California Institute of Technology, the Jet Propulsion Laboratory, the Heising–Simons Foundation (grant Nos. 2015-129, 2017-318, 2019-1312, and 2023-4598), the Simons Foundation, and the NSF under grant AST-1611623. The computations presented here were conducted at the Resnick High Performance Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. W. M. Keck Observatory access was supported by Northwestern University and the Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA). This research has made use of the Keck Observatory Archive (KOA), which is operated by the W. M. Keck Observatory and the NASA Exoplanet Science Institute (NExScI), under contract with the National Aeronautics and Space Administration. The data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

\n\n

Keck:II (KPIC) -

\n\n

petitRADTRANS (Mollière et al. 2019), dynesty (Speagle 2020), species (Stolker et al. 2020)

", "abstract": "

M dwarfs are common host stars to exoplanets but often lack atmospheric abundance measurements. Late-M dwarfs are also good analogs to the youngest substellar companions, which share similar Teff ∼ 2300–2800 K. We present atmospheric analyses for the M7.5 companion HIP 55507 B and its K6V primary star with Keck/KPIC high-resolution (R ∼ 35,000) K-band spectroscopy. First, by including KPIC relative radial velocities between the primary and secondary in the orbit fit, we improve the dynamical mass precision by 60% and find M_B = 88.0_(−3.2)^(+3.4) M_Jup, putting HIP 55507 B above the stellar–substellar boundary. We also find that HIP 55507 B orbits its K6V primary star with a = 38\u208b\u2083\u207a\u2074 au and e = 0.40 ± 0.04. From atmospheric retrievals of HIP 55507 B, we measure [C/H] = 0.24 ± 0.13, [O/H] = 0.15 ± 0.13, and C/O = 0.67 ± 0.04. Moreover, we strongly detect 13CO (7.8σ significance) and tentatively detect H218O (3.7σ significance) in the companion's atmosphere and measure 12C/13C = 98\u208b\u2082\u2082\u207a²\u2078 and H\u208216O/H\u208218O = 240\u208b\u2088\u2080\u207a¹\u2074\u2075 after accounting for systematic errors. From a simplified retrieval analysis of HIP 55507 A, we measure 12C/13C = 79\u208b\u2081\u2086\u207a²¹ and C16O/C18O = 288\u208b\u2087\u2080\u207a¹²\u2075 for the primary star. These results demonstrate that HIP 55507 A and B have consistent 12C/13C and 16O/18O to the <1σ level, as expected for a chemically homogeneous binary system. Given the similar flux ratios and separations between HIP 55507 AB and systems with young substellar companions, our results open the door to systematically measuring 13CO and H\u208218O abundances in the atmospheres of substellar or even planetary-mass companions with similar spectral types.

", "date": "2024-02-10", "date_type": "published", "publication": "Astrophysical Journal", "volume": "962", "number": "1", "publisher": "American Astronomical Society", "pagerange": "10", "issn": "0004-637X", "official_url": "https://authors.library.caltech.edu/records/h03b9-38d60", "funders": { "items": [ { "grant_number": "80NSSC23K1434" }, {}, { "grant_number": "80NSSC19K1423" }, {}, {}, { "grant_number": "2015-129" }, { "grant_number": "2017-318" }, { "grant_number": "2019-1312" }, { "grant_number": "2023-4598" }, {}, { "grant_number": "AST-1611623" }, {}, { "grant_number": "Center for Interdisciplinary Exploration and Research in Astrophysics" }, {} ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/1538-4357/ad1243", "primary_object": { "basename": "Xuan_2024_ApJ_962_10.pdf", "url": "https://authors.library.caltech.edu/records/h03b9-38d60/files/Xuan_2024_ApJ_962_10.pdf" }, "pub_year": "2024", "author_list": "Xuan, Jerry W.; Wang, Jason; et al." }, { "id": "https://authors.library.caltech.edu/records/y0dyj-gv779", "eprint_status": "archive", "datestamp": "2024-06-27 19:56:10", "lastmod": "2024-06-27 19:56:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Statt-Michael-J", "name": { "family": "Statt", "given": "Michael J." }, "orcid": "0000-0002-7923-6029" }, { "id": "Rohr-Brian-A", "name": { "family": "Rohr", "given": "Brian A." }, "orcid": "0000-0003-4696-0149" }, { "id": "Guevarra-Dan", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Event-driven data management with cloud computing for extensible materials acceleration platforms", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.

\n\n

This work was primarily funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DE-SC0023139 and the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award DE-SC0021266. Additional support was provided by the Toyota Research Institute through their Accelerated Materials Design and Discovery program and the Resnick Sustainability Institute through an RSI Impact Grant.

\n\n

Modelyst LLC implements custom data management systems in a professional context. J. M. G. is a consultant for companies that aim to accelerate materials discovery.

", "abstract": "
\n

The materials research community is increasingly using automation and artificial intelligence (AI) to accelerate research and development. A materials acceleration platform (MAP) typically encompasses several experimental techniques or instruments to establish a synthesis-characterization-evaluation workflow. With the advancement of workflow orchestration software and AI experiment design, the scope and complexity of MAPs are increasing, however each MAP typically operates as a standalone entity with dedicated experiment, compute, and database resources. The data from each MAP is thus siloed until subsequent efforts to integrate data into complex schema such as knowledge graphs. To lower the latency of data integration and establish an extensible community of MAPs, we must expand our automation efforts to include data handling that is decoupled from the resources of each MAP. Event-driven pipelines are well established in the computational community for building decoupled data processing systems. Such pipelines can be difficult to implement de novo due to their distributed nature and complex error handling. Fortunately, the broader computational science community has established a suite of cloud services that are well suited for this task. By leveraging cloud computing resources to establish event-driven data management, the MAP community can better realize the ideals of extensibility and interoperability in materials chemistry research.

\n
", "date": "2024-02", "date_type": "published", "publication": "Digital Discovery", "volume": "3", "number": "2", "publisher": "Royal Society of Chemistry", "pagerange": "238-242", "issn": "2635-098X", "official_url": "https://authors.library.caltech.edu/records/y0dyj-gv779", "funders": { "items": [ { "grant_number": "DE-SC0023139" }, { "grant_number": "DE-SC0021266" }, {}, {} ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d3dd00220a", "primary_object": { "basename": "d3dd00220a.pdf", "url": "https://authors.library.caltech.edu/records/y0dyj-gv779/files/d3dd00220a.pdf" }, "pub_year": "2024", "author_list": "Statt, Michael J.; Rohr, Brian A.; et al." }, { "id": "https://authors.library.caltech.edu/records/knwzk-sb869", "eprint_status": "archive", "datestamp": "2024-06-24 16:43:00", "lastmod": "2024-08-01 00:02:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Peng", "given": "Shirui" }, "orcid": "0000-0002-4616-4604" }, { "id": "Callies-J", "name": { "family": "Callies", "given": "J\u00f6rn" }, "orcid": "0000-0002-6815-1230" }, { "name": { "family": "Wu", "given": "Wenbo" }, "orcid": "0000-0002-6249-8065" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" } ] }, "title": "Seismic Ocean Thermometry of the Kuroshio Extension Region", "ispublished": "pub", "full_text_status": "public", "note": "

© 2024 American Geophysical Union.

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This material is based upon work supported in part by the Resnick Sustainability Institute and in part by the National Science Foundation under Grant OCE-2023161. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.

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Conceptualization: Jörn Callies, Wenbo Wu, Zhongwen Zhan

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Data curation: Wenbo Wu

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Formal analysis: Shirui Peng, Wenbo Wu

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Funding acquisition: Jörn Callies, Zhongwen Zhan

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Investigation: Shirui Peng, Jörn Callies, Wenbo Wu, Zhongwen Zhan

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Methodology: Shirui Peng, Jörn Callies, Wenbo Wu, Zhongwen Zhan

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Resources: Jörn Callies, Wenbo Wu, Zhongwen Zhan

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Software: Shirui Peng, Jörn Callies, Wenbo Wu

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Supervision: Jörn Callies, Wenbo Wu, Zhongwen Zhan

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Validation: Shirui Peng, Jörn Callies, Wenbo Wu

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Visualization: Shirui Peng

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Writing – original draft: Shirui Peng

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Writing – review & editing: Shirui Peng, Jörn Callies, Wenbo Wu, Zhongwen Zhan

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The IMS hydrophone data are available directly from the CTBTO upon request and signing a confidentiality agreement to access the virtual Data Exploitation Centre (vDEC: https://www.ctbto.org/resources/for-researchers-experts/vdec) (Preparatory Commission For The Comprehensive Nuclear Test-Ban Treaty Organization, 2002). All seismic data were downloaded through IRIS Data Management Center, including the seismic networks II (Scripps Institution of Oceanography, 1986), IU (Albuquerque Seismological Laboratory/USGS, 2014), PS (University of Tokyo, 1989), G (Institut de physique du globe de Paris (IPGP) & École et Observatoire des Sciences de la Terre de Strasbourg (EOST), 1982). Global Seismographic Network (GSN) is a cooperative scientific facility operated jointly by the Incorporated Research Institutions for Seismology (IRIS), the United States Geological Survey (USGS) and the National Science Foundation (NSF), under Cooperative Agreement EAR-1261681. Bathymetry data were downloaded from and freely available at https://download.gebco.net/ (GEBCO Compilation Group, 2023). The sediment thickness data were downloaded from https://ngdc.noaa.gov/mgg/sedthick/ (Straume et al., 2019). Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it (http://www.argo.ucsd.edu, http://argo.jcommops.org). The Argo Program is part of the Global Ocean Observing System (Argo, 2000). The ECCO data were available at https://podaac.jpl.nasa.gov/dataset/ECCO_L4_TEMP_SALINITY_05DEG_DAILY_V4R4 (Fenty & Wang, 2020). The seismic-wave processing code is available at https://github.com/joernc/sot (joernc et al., 2023).

\n\n
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", "abstract": "
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Seismic ocean thermometry uses sound waves generated by repeating earthquakes to measure temperature change in the deep ocean. In this study, waves generated by earthquakes along the Japan Trench and received at Wake Island are used to constrain temperature variations in the Kuroshio Extension region. This region is characterized by energetic mesoscale eddies and large decadal variability, posing a challenging sampling problem for conventional ocean observations. The seismic measurements are obtained from a hydrophone station off and a seismic station on Wake Island, with the seismic station's digital record reaching back to 1997. These measurements are combined in an inversion for the time and azimuth dependence of the range-averaged deep temperatures, revealing lateral and temporal variations due to Kuroshio Extension meanders, mesoscale eddies, and decadal water mass displacements. These results highlight the potential of seismic ocean thermometry for better constraining the variability and trends in deep-ocean temperatures. By overcoming the aliasing problem of point measurements, these measurements complement existing ship- and float-based hydrographic measurements.

\n
", "date": "2024-02", "date_type": "published", "publication": "Journal of Geophysical Research: Oceans", "volume": "129", "number": "2", "publisher": "American Geophysical Union", "pagerange": "e2023JC020636", "issn": "2169-9275", "official_url": "https://authors.library.caltech.edu/records/knwzk-sb869", "funders": { "items": [ {}, { "grant_number": "OCE\u20102023161" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Seismological-Laboratory" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2023jc020636", "primary_object": { "basename": "JGR Oceans - 2024 - Peng - Seismic Ocean Thermometry of the Kuroshio Extension Region.pdf", "url": "https://authors.library.caltech.edu/records/knwzk-sb869/files/JGR Oceans - 2024 - Peng - Seismic Ocean Thermometry of the Kuroshio Extension Region.pdf" }, "pub_year": "2024", "author_list": "Peng, Shirui; Callies, J\u00f6rn; et al." }, { "id": "https://authors.library.caltech.edu/records/knteb-fv524", "eprint_status": "archive", "datestamp": "2024-01-22 23:05:49", "lastmod": "2026-03-03 18:36:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xu-Changhao", "name": { "family": "Xu", "given": "Changhao" }, "orcid": "0000-0002-6817-3341" }, { "id": "Song-Yu", "name": { "family": "Song", "given": "Yu" }, "orcid": "0000-0002-4185-2256" }, { "id": "Sempionatto-Juliane-R", "name": { "family": "Sempionatto", "given": "Juliane R." }, "orcid": "0000-0003-2431-9019" }, { "id": "Solomon-Samuel-A", "name": { "family": "Solomon", "given": "Samuel A." } }, { "id": "Yu-You", "name": { "family": "Yu", "given": "You" }, "orcid": "0000-0001-7059-7023" }, { "id": "Nyein-Hnin-Y-Y", "name": { "family": "Nyein", "given": "Hnin Y. Y." }, "orcid": "0000-0002-5692-6182" }, { "id": "Tay-Roland-Yingjie", "name": { "family": "Tay", "given": "Roland Yingjie" }, "orcid": "0000-0002-3341-0984" }, { "id": "Li-Jiahong", "name": { "family": "Li", "given": "Jiahong" } }, { "id": "Heng-Wenzheng", "name": { "family": "Heng", "given": "Wenzheng" } }, { "id": "Min-Jihong", "name": { "family": "Min", "given": "Jihong" }, "orcid": "0000-0002-5788-1473" }, { "id": "Lao-Alison", "name": { "family": "Lao", "given": "Alison" }, "orcid": "0000-0003-2634-4920" }, { "id": "Hsiai-Tzung-K", "name": { "family": "Hsiai", "given": "Tzung K." }, "orcid": "0000-0003-1734-0792" }, { "id": "Sumner-Jennifer-A", "name": { "family": "Sumner", "given": "Jennifer A." }, "orcid": "0000-0002-0217-7171" }, { "id": "Gao-Wei", "name": { "family": "Gao", "given": "Wei" }, "orcid": "0000-0002-8503-4562" } ] }, "title": "A physicochemical-sensing electronic skin for stress response monitoring", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; Instrumentation; Electronic, Optical and Magnetic Materials", "note": "

© The Author(s), under exclusive licence to Springer Nature Limited 2024. 

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This work was funded by the Translational Research Institute for Space Health through NASA NNX16AO69A, Office of Naval Research grant nos. N00014-21-1-2483 and N00014-21-1-2845, Army Research Office grant no. W911NF-23-1-0041, National Institutes of Health grant nos. R01HL155815 and R21DK13266, National Science Foundation grant no. 2145802, National Academy of Medicine Catalyst Award and High Impact Pilot Research Award no. T31IP1666 from the Tobacco-Related Disease Research Program and Heritage Medical Research Institute (all to W.G.). T.K.H. acknowledges the support from National Institutes of Health grant nos. T32HL144449 and T32EB027629. C.X. acknowledges support from an Amazon AI4Science Fellowship. ICP-MS instrumentation at the Resnick Sustainability Institute’s Water and Environment Lab at the California Institute of Technology was used in this work with the assistance of N. Dalleska. We acknowledge critical support and infrastructure provided for this work by the Kavli Nanoscience Institute at Caltech and Center for Transmission Electron Microscopy at the University of California Irvine, and we thank M. Hunt and M. Xu for their help.

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These authors contributed equally: Changhao Xu, Yu Song, Juliane R. Sempionatto, Samuel A. Solomon.

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W.G. and C.X. conceived the project. C.X. led the sensors and CARES platform development. C.X., Y.S. and J.R.S. led the platform characterization and human studies. S.A.S. and J.L. contributed to the data processing and feature extraction. H.Y.Y.N. contributed to sensor development. Y.Y., R.Y.T. and A.L. contributed to sensor characterization and testing. W.H. and J.M. contributed to wireless system development. T.K.H. and J.A.S. contributed to the human study design. W.G., C.X., Y.S., J.R.S. and S.A.S. cowrote the paper. All authors contributed to the data analysis and provided feedback on the manuscript.

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The multimodal data collected by the CARES from human subjects is available at https://github.com/CARES-eskin/StressData. All other data that support the findings of this study are available from the corresponding author on reasonable request.

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The authors declare no competing interests.

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", "abstract": "
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Approaches to quantify stress responses typically rely on subjective surveys and questionnaires. Wearable sensors can potentially be used to continuously monitor stress-relevant biomarkers. However, the biological stress response is spread across the nervous, endocrine and immune systems, and the capabilities of current sensors are not sufficient for condition-specific stress response evaluation. Here we report an electronic skin for stress response assessment that non-invasively monitors three vital signs (pulse waveform, galvanic skin response and skin temperature) and six molecular biomarkers in human sweat (glucose, lactate, uric acid, sodium ions, potassium ions and ammonium). We develop a general approach to prepare electrochemical sensors that relies on analogous composite materials for stabilizing and conserving sensor interfaces. The resulting sensors offer long-term sweat biomarker analysis of more than 100 h with high stability. We show that the electronic skin can provide continuous multimodal physicochemical monitoring over a 24-hour period and during different daily activities. With the help of a machine learning pipeline, we also show that the platform can differentiate three stressors with an accuracy of 98.0% and quantify psychological stress responses with a confidence level of 98.7%.

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", "date": "2024-02", "date_type": "published", "publication": "Nature Electronics", "volume": "7", "number": "2", "publisher": "Nature Publishing Group", "pagerange": "168-179", "issn": "2520-1131", "official_url": "https://authors.library.caltech.edu/records/knteb-fv524", "funders": { "items": [ { "grant_number": "NNX16AO69A" }, { "grant_number": "N00014-21-1-2483" }, { "grant_number": "N00014-21-1-2845" }, { "grant_number": "W911NF-23-1-0041" }, { "grant_number": "R01HL155815" }, { "grant_number": "R21DK13266" }, { "grant_number": "ECCS-2145802" }, {}, { "grant_number": "T31IP1666" }, { "grant_number": "Heritage Medical Research Institute" }, { "grant_number": "T32HL144449" }, { "grant_number": "T32EB027629" }, { "grant_number": "Amazon AI4Science Fellowship" } ] }, "local_group": { "items": [ { "id": "Heritage-Medical-Research-Institute" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1038/s41928-023-01116-6", "pmcid": "PMC10906959", "primary_object": { "basename": "41928_2023_1116_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/knteb-fv524/files/41928_2023_1116_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41928_2023_1116_MOESM4_ESM.mov", "url": "https://authors.library.caltech.edu/records/knteb-fv524/files/41928_2023_1116_MOESM4_ESM.mov" }, { "basename": "41928_2023_1116_MOESM3_ESM.mov", "url": "https://authors.library.caltech.edu/records/knteb-fv524/files/41928_2023_1116_MOESM3_ESM.mov" } ], "pub_year": "2024", "author_list": "Xu, Changhao; Song, Yu; et al." }, { "id": "https://authors.library.caltech.edu/records/hncah-g5h50", "eprint_status": "archive", "datestamp": "2024-03-06 00:42:14", "lastmod": "2024-03-18 20:08:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulte-Samuel-J", "name": { "family": "Schulte", "given": "Samuel J." }, "orcid": "0000-0001-9982-6504" }, { "id": "Fornace-Mark-E", "name": { "family": "Fornace", "given": "Mark E." }, "orcid": "0000-0002-5829-5839" }, { "id": "Hall-John-K", "name": { "family": "Hall", "given": "John K." }, "orcid": "0009-0005-5120-5940" }, { "id": "Shin-Grace-J", "name": { "family": "Shin", "given": "Grace J." }, "orcid": "0009-0004-7778-6328" }, { "id": "Pierce-N-A", "name": { "family": "Pierce", "given": "Niles A." }, "orcid": "0000-0003-2367-4406" } ] }, "title": "HCR spectral imaging: 10-plex, quantitative, high-resolution RNA and protein imaging in highly autofluorescent samples", "ispublished": "pub", "full_text_status": "public", "keywords": "Developmental Biology; Molecular Biology", "note": "
© 2024. Published by The Company of Biologists Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
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We thank A. Kahan of the V. Gradinaru Lab for the gift of mouse brain sections during initial validation; M. E. Bronner for reading a draft of the manuscript; and the following resources within the Beckman Institute at Caltech: Molecular Technologies for providing HCR reagents, G. Spigolon of the Biological Imaging Facility for assistance with imaging, and the Zebrafish Facility for providing zebrafish embryos. The Leica Stellaris 8 confocal microscope in the Biological Imaging Facility within the Beckman Institute at Caltech was purchased with support from Caltech and the following Caltech entities: the Beckman Institute, the Resnick Sustainability Institute, the Division of Biology & Biological Engineering, and the Merkin Institute for Translational Research.

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This work was funded by the National Institute of Biomedical Imaging and Bioengineering (R01EB006192), a National Institute of General Medical Sciences training grant (GM008042 to S.J.S.) and the Beckman Institute, California Institute of Technology (PMTC). Open Access funding provided by California Institute of Technology. Deposited in PMC for immediate release.

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Conceptualization: N.A.P.; Methodology: S.J.S., M.E.F., N.A.P.; Software: M.E.F.; Validation: S.J.S., M.E.F., J.K.H.; Investigation: S.J.S., J.K.H., G.J.S.; Writing - original draft: S.J.S., N.A.P.; Writing - review & editing: S.J.S., M.E.F., J.K.H., G.J.S., N.A.P.; Visualization: S.J.S., M.E.F.; Supervision: N.A.P.; Project administration: N.A.P.; Funding acquisition: N.A.P.

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All relevant data can be found within the article and its supplementary information.

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The authors declare competing financial interests in the form of patents, pending patent applications, and the startup company Molecular Instruments, Inc.

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", "abstract": "
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Signal amplification based on the mechanism of hybridization chain reaction (HCR) provides a unified framework for multiplex, quantitative, high-resolution imaging of RNA and protein targets in highly autofluorescent samples. With conventional bandpass imaging, multiplexing is typically limited to four or five targets owing to the difficulty in separating signals generated by fluorophores with overlapping spectra. Spectral imaging has offered the conceptual promise of higher levels of multiplexing, but it has been challenging to realize this potential in highly autofluorescent samples, including whole-mount vertebrate embryos. Here, we demonstrate robust HCR spectral imaging with linear unmixing, enabling simultaneous imaging of ten RNA and/or protein targets in whole-mount zebrafish embryos and mouse brain sections. Further, we demonstrate that the amplified and unmixed signal in each of the ten channels is quantitative, enabling accurate and precise relative quantitation of RNA and/or protein targets with subcellular resolution, and RNA absolute quantitation with single-molecule resolution, in the anatomical context of highly autofluorescent samples.

\n\n
", "date": "2024-02", "date_type": "published", "publication": "Development", "volume": "151", "number": "4", "publisher": "Company of Biologists", "pagerange": "dev202307", "issn": "0950-1991", "official_url": "https://authors.library.caltech.edu/records/hncah-g5h50", "funders": { "items": [ { "grant_number": "Beckman Institute" }, { "grant_number": "R01EB006192" }, { "grant_number": "GM008042" } ] }, "local_group": { "items": [ { "id": "Division-of-Biology-and-Biological-Engineering" }, { "id": "Richard-Merkin-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1242/dev.202307", "pmcid": "PMC10941662", "primary_object": { "basename": "DownloadCombinedArticleAndSupplmentPdf.pdf", "url": "https://authors.library.caltech.edu/records/hncah-g5h50/files/DownloadCombinedArticleAndSupplmentPdf.pdf" }, "pub_year": "2024", "author_list": "Schulte, Samuel J.; Fornace, Mark E.; et al." }, { "id": "https://authors.library.caltech.edu/records/aprev-2xs06", "eprint_status": "archive", "datestamp": "2024-01-31 23:53:39", "lastmod": "2025-04-23 21:32:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Aitbekova-Aisulu", "name": { "family": "Aitbekova", "given": "Aisulu" }, "orcid": "0000-0003-3309-1220" }, { "id": "Watkins-Nicholas", "name": { "family": "Watkins", "given": "Nicholas" }, "orcid": "0000-0001-7251-9387" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Jahelka-Phillip", "name": { "family": "Jahelka", "given": "Phillip" }, "orcid": "0000-0002-1460-7933" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Molecular Additives Improve the Selectivity of CO\u2082 Photoelectrochemical Reduction over Gold Nanoparticles on Gallium Nitride", "ispublished": "pub", "full_text_status": "public", "keywords": "Mechanical Engineering; Condensed Matter Physics; General Materials Science; General Chemistry; Bioengineering", "note": "

© 2024 American Chemical Society.

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This material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub, under Grant DE-SC0021266. Part of this work was carried out at the Molecular Materials Research Center in the Beckman Institute of the California Institute of Technology. The Resnick Sustainability Institute is acknowledged for support of enabling facilities at Caltech. The authors thank Yungchieh Lai for performing ICP-MS measurements and Azhar Carim for helping collect cross-sectional SEM data. A.A. acknowledges support from the Kavli Nanoscience Institute Postdoctoral Fellowship.

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The authors declare no competing financial interest.

", "abstract": "
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Photoelectrochemical CO2 reduction (CO2R) is an appealing solution for converting carbon dioxide into higher-value products. However, CO2R in aqueous electrolytes suffers from poor selectivity due to the competitive hydrogen evolution reaction that is dominant on semiconductor surfaces in aqueous electrolytes. We demonstrate that functionalizing gold/p-type gallium nitride devices with a film derived from diphenyliodonium triflate suppresses hydrogen generation from 90% to 18%. As a result, we observe increases in the Faradaic efficiency and partial current density for carbon monoxide of 50% and 3-fold, respectively. Furthermore, we demonstrate through optical absorption measurements that the molecular film employed herein, regardless of thickness, does not affect the photocathode’s light absorption. Altogether, this study provides a rigorous platform for elucidating the catalytic structure–property relationships to enable engineering of active, stable, and selective materials for photoelectrochemical CO2R.

\n
", "date": "2024-01-31", "date_type": "published", "publication": "Nano Letters", "volume": "24", "number": "4", "publisher": "American Chemical Society", "pagerange": "1090-1095", "issn": "1530-6984", "official_url": "https://authors.library.caltech.edu/records/aprev-2xs06", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, { "grant_number": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acs.nanolett.3c03590", "primary_object": { "basename": "nl3c03590_si_001.pdf", "url": "https://authors.library.caltech.edu/records/aprev-2xs06/files/nl3c03590_si_001.pdf" }, "pub_year": "2024", "author_list": "Aitbekova, Aisulu; Watkins, Nicholas; et al." }, { "id": "https://authors.library.caltech.edu/records/8jt8t-2a264", "eprint_status": "archive", "datestamp": "2024-01-24 18:02:48", "lastmod": "2024-01-24 18:02:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Jones", "given": "Ethan M." }, "orcid": "0000-0003-4813-7148" }, { "name": { "family": "Marken", "given": "John P." }, "orcid": "0000-0001-9696-088X" }, { "name": { "family": "Silver", "given": "Pamela A." }, "orcid": "0000-0002-7856-4071" } ] }, "title": "Synthetic microbiology in sustainability applications", "ispublished": "pub", "full_text_status": "public", "keywords": "General Immunology and Microbiology; Microbiology; Infectious Diseases", "note": "

© Springer Nature Limited 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

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The authors thank Q. Justman for the insightful comments and revisions of the manuscript.

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E.M.J. and J.P.M. conceptualized the narrative framework, researched the literature and wrote the article. All authors contributed to discussions of the content and reviewed and edited the manuscript.

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Pamela Silver is a founder of KulaBio and Circe Bioscience. The other authors declare no competing interests.

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", "abstract": "
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Microorganisms are a promising means to address many societal sustainability challenges owing to their ability to thrive in diverse environments and interface with the microscale chemical world via diverse metabolic capacities. Synthetic biology can engineer microorganisms by rewiring their regulatory networks or introducing new functionalities, enhancing their utility for target applications. In this Review, we provide a broad, high-level overview of various research efforts addressing sustainability challenges through synthetic biology, emphasizing foundational microbiological research questions that can accelerate the development of these efforts. We introduce an organizational framework that categorizes these efforts along three domains — factory, farm and field — that are defined by the extent to which the engineered microorganisms interface with the natural external environment. Different application areas within the same domain share many fundamental challenges, highlighting productive opportunities for cross-disciplinary collaborations between researchers working in historically disparate fields.

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", "date": "2024-01-22", "date_type": "published", "publication": "Nature Reviews Microbiology", "publisher": "Nature Publishing Group", "issn": "1740-1526", "official_url": "https://authors.library.caltech.edu/records/8jt8t-2a264", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41579-023-01007-9", "pub_year": "2024", "author_list": "Jones, Ethan M.; Marken, John P.; et al." }, { "id": "https://authors.library.caltech.edu/records/wcnwq-0mw52", "eprint_status": "archive", "datestamp": "2024-01-12 18:10:42", "lastmod": "2025-04-25 16:47:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Larsson-Elin-M", "name": { "family": "Larsson", "given": "Elin M." }, "orcid": "0000-0003-1341-5937" }, { "id": "Murray-R-M", "name": { "family": "Murray", "given": "Richard M." }, "orcid": "0000-0002-5785-7481" }, { "id": "Newman-D-K", "name": { "family": "Newman", "given": "Dianne K." }, "orcid": "0000-0003-1647-1918" } ] }, "title": "Engineering the Soil Bacterium Pseudomonas synxantha 2\u201379 into a Ratiometric Bioreporter for Phosphorus Limitation", "ispublished": "pub", "full_text_status": "public", "keywords": "Biochemistry, Genetics and Molecular Biology (miscellaneous); Biomedical Engineering; General Medicine", "note": "
© 2024 American Chemical Society.
\n\n
\n

This work was supported by the National Science Foundation Division of Molecular and Cellular Biosciences (MCB-2016137 to F.H.A). D.J.W. acknowledges support from the National Science Foundation Graduate Research Fellowship (DGE-1745301). R.M. acknowledges support from the Swiss National Science Foundation (SNSF) Early Mobility Postdoctoral Fellowship (P2ELP2_195118). K.M.S. acknowledges support from NIH Ruth L. Kirschstein National Research Service Award (1F32GM145123-01A1). We thank Dr. Michael K. Takase and Lawrence M. Henling for assistance with X-ray crystallographic data collection and Dr. Scott C. Virgil for the maintenance of the Caltech Center for Catalysis and Chemical Synthesis (3CS). We thank Dr. Mona Shahgoli for mass spectrometry assistance and Dr. David VanderVelde for the maintenance of the Caltech NMR facility. We also thank Dr. Sabine Brinkmann-Chen for the helpful discussions and comments on the manuscript. The paper is adapted from a thesis, which is available free of charge via the Internet at https://resolver.caltech.edu/CaltechTHESIS:09022023-064950039.

\n
\n
\n
\n
\n
 
\n
\n
\n
\n\n

D.J.W. and R.M. contributed equally.

\n\n

The Supporting Information is available free of charge at https://pubs.acs.org/doi/10.1021/jacs.3c11722.

\n\n\n

The authors declare no competing financial interest.

", "abstract": "
\n

Microbial bioreporters hold promise for addressing challenges in medical and environmental applications. However, the difficulty in ensuring their stable persistence and function within the target environment remains a challenge. One strategy is to integrate information about the host strain and target environment into the design-build-test cycle of the bioreporter itself. Here, we present a case study for such an environmentally motivated design process by engineering the wheat commensal bacterium Pseudomonas synxantha 2–79 into a ratiometric bioreporter for phosphorus limitation. Comparative analysis showed that an exogenous P-responsive promoter outperformed its native counterparts. This reporter can selectively sense and report phosphorus limitation at plant-relevant concentrations of 25–100 μM without cross-activation from carbon or nitrogen limitation or high cell densities. Its performance is robust over a field-relevant pH range (5.8–8), and it responds only to inorganic phosphorus, even in the presence of common soil organic P. Finally, we used fluorescein-calibrated flow cytometry to assess whether the reporter’s performance in shaken liquid culture predicts its performance in soil, finding that although the reporter is still functional at the bulk level, its variability in performance increases when grown in a soil slurry as compared to planktonic culture, with a fraction of the population not expressing the reporter proteins. Together, our environmentally aware design process provides an example of how laboratory bioengineering efforts can generate microbes with a greater promise to function reliably in their applied contexts.

\n
\n
\n
 
\n
", "date": "2024-01-19", "date_type": "published", "publication": "ACS Synthetic Biology", "volume": "13", "number": "1", "publisher": "American Chemical Society", "pagerange": "384-393", "issn": "2161-5063", "official_url": "https://authors.library.caltech.edu/records/wcnwq-0mw52", "funders": { "items": [ { "grant_number": "W911NF-19-D-0001" }, { "agency": "Resnick Sustainability Institute, Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Biology-and-Biological-Engineering" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acssynbio.3c00642", "primary_object": { "basename": "ja3c11722_si_001.pdf", "url": "https://authors.library.caltech.edu/records/wcnwq-0mw52/files/ja3c11722_si_001.pdf" }, "pub_year": "2024", "author_list": "Larsson, Elin M.; Murray, Richard M.; et al." }, { "id": "https://authors.library.caltech.edu/records/8vnhh-r4p06", "eprint_status": "archive", "datestamp": "2024-01-18 23:40:06", "lastmod": "2024-01-18 23:44:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "Begu\u0161i\u0107", "given": "Tomislav" }, "orcid": "0000-0002-7942-4134" }, { "name": { "family": "Gray", "given": "Johnnie" }, "orcid": "0000-0001-9461-3024" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Fast and converged classical simulations of evidence for the utility of quantum computing before fault tolerance", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

© 2024 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).

\n\n

J.G. thanks N. Pancotti for many fruitful discussions of BP and TNs. We thank the authors of (12–15, 17)for sharing data presented in Fig. 9.

\n\n

We were supported by the US Department of Energy, Office of Science, Office of Advanced Scientific Computing Research and Office of Basic Energy Sciences, Scientific Discovery through Advanced Computing (SciDAC) program under award number DE-SC0022088. T.B. acknowledges financial support from the Swiss National Science Foundation through the Postdoc Mobility Fellowship (grant number P500PN-214214). G.K.-L.C. is a Simons Investigator in Physics. Computations presented here were partly conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a US Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under contract no. DE-AC02-05CH11231 using NERSC award BES-ERCAP0024087.

\n\n

G.K.-L.C. conceptualized and supervised the work. J.G. and T.B. participated in conceptualization, implemented the computational methods, carried out simulations, and prepared the data and figures. All authors contributed to the analysis of the results and writing of the manuscript.

\n\n

All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Data presented in Figs. 3 to 5 are available at www.github.com/tbegusic/arxiv-2308.05077-data (Zenodo access code: www.doi.org/10.5281/zenodo.10223349). Code for running the SPD and TN simulations is available on GitHub and Zenodo (SPD, www.github.com/tbegusic/spd and https://doi.org/10.5281/zenodo.10456459 and TN, www.github.com/jcmgray/mixpic-bp-quantum-dynamics and doi.org/10.5281/zenodo.10458595).

\n\n

G.K.-L.C. is part owner of QSimulate Inc. and has served as a scientific consultant to the Flatiron Institute. Between 2019 and 2021, he was on the advisory board of the Qingdao Institute of Theoretical and Computational Chemistry. He is the Chief Scientific Advisor to QSimulate and an Associate Researcher of the HK Quantum AI lab. The other authors declare that they have no competing interests.

", "abstract": "A recent quantum simulation of observables of the kicked Ising model on 127 qubits implemented circuits that exceed the capabilities of exact classical simulation. We show that several approximate classical methods, based on sparse Pauli dynamics and tensor network algorithms, can simulate these observables orders of magnitude faster than the quantum experiment and can also be systematically converged beyond the experimental accuracy. Our most accurate technique combines a mixed Schr\u00f6dinger and Heisenberg tensor network representation with the Bethe free entropy relation of belief propagation to compute expectation values with an effective wave function\u2013operator sandwich bond dimension >16,000,000, achieving an absolute accuracy, without extrapolation, in the observables of <0.01, which is converged for many practical purposes. We thereby identify inaccuracies in the experimental extrapolations and suggest how future experiments can be implemented to increase the classical hardness.", "date": "2024-01-19", "date_type": "published", "publication": "Science Advances", "volume": "10", "number": "3", "publisher": "American Association for the Advancement of Science", "pagerange": "eadk4321", "issn": "2375-2548", "official_url": "https://authors.library.caltech.edu/records/8vnhh-r4p06", "funders": { "items": [ { "grant_number": "DE-SC0022088" }, { "grant_number": "P500PN-214214" }, {}, {}, { "grant_number": "DE-AC02-05CH11231" }, { "grant_number": "BES-ERCAP0024087" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.adk4321", "primary_object": { "basename": "sciadv.adk4321.pdf", "url": "https://authors.library.caltech.edu/records/8vnhh-r4p06/files/sciadv.adk4321.pdf" }, "related_objects": [ { "basename": "sciadv.adk4321_sm.pdf", "url": "https://authors.library.caltech.edu/records/8vnhh-r4p06/files/sciadv.adk4321_sm.pdf" } ], "pub_year": "2024", "author_list": "Begu\u0161i\u0107, Tomislav; Gray, Johnnie; et al." }, { "id": "https://authors.library.caltech.edu/records/zexft-t7k79", "eprint_status": "archive", "datestamp": "2023-12-22 19:12:03", "lastmod": "2024-06-13 16:48:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Goyal-Akshit", "name": { "family": "Goyal", "given": "Akshit" }, "orcid": "0000-0002-9425-8269" }, { "id": "Flamholtz-Avi-I", "name": { "family": "Flamholz", "given": "Avi I." }, "orcid": "0000-0002-9278-5479" }, { "id": "Petroff-Alexander-P", "name": { "family": "Petroff", "given": "Alexander P." }, "orcid": "0000-0002-9612-6593" }, { "id": "Murugan-Arvind", "name": { "family": "Murugan", "given": "Arvind" }, "orcid": "0000-0001-5464-917X" } ] }, "title": "Closed ecosystems extract energy through self-organized nutrient cycles", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

\u00a9 2023 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).

\n\n

We thank the Kavli Institute for Theoretical Physics, University of California, Santa Barbara (UCSB), where this project took root. We thank G. Birzu, O.X. Cordero, W. W. Fischer, P. Falkowski, J. Goldford, S. Kuehn, S. Maslov, A. Narla, and M. Tikhonov for discussions. This research was supported in part by the NSF under grant number NSF PHY-1748958. A.G. is supported by the Gordon and Betty Moore Foundation as a Physics of Living Systems Fellow through grant number GBMF4513. A.I.F is supported by the Jane Coffin Childs Memorial Fund for Medical Research. A.M acknowledges support from the NSF through the Center for Living Systems (grant no. 2317138) and the National Institute of General Medical Sciences (NIGMS) of the NIH under award number R35GM151211. A.P.P. was supported by NSF grant number PHY-2042150.

\n\n

A.G., A.I.F., A.P.P., and A.M. designed research; A.G. and A.M. performed research; A.G. contributed new reagents/analytic tools; A.G. analyzed data; and A.G., A.I.F., and A.M. wrote the paper.

\n\n

There are no data underlying this work.

\n\n

The authors declare no competing interest.

", "abstract": "Our planet is a self-sustaining ecosystem powered by light energy from the sun, but roughly closed to matter. Many ecosystems on Earth are also approximately closed to matter and recycle nutrients by self-organizing stable nutrient cycles, e.g., microbial mats, lakes, open ocean gyres. However, existing ecological models do not exhibit the self-organization and dynamical stability widely observed in such planetary-scale ecosystems. Here, we advance a conceptual model that explains the self-organization, stability, and emergent features of closed microbial ecosystems. Our model incorporates the bioenergetics of metabolism into an ecological framework. By studying this model, we uncover a crucial thermodynamic feedback loop that enables metabolically diverse communities to almost always stabilize nutrient cycles. Surprisingly, highly diverse communities self-organize to extract\n \n \n \u2248\n \n \n 10\n \n \n %\n \n \n of the maximum extractable energy, or\n \n \n \u2248\n \n \n 100 fold more than randomized communities. Further, with increasing diversity, distinct ecosystems show strongly correlated fluxes through nutrient cycles. However, as the driving force from light increases, the fluxes of nutrient cycles become more variable and species-dependent. Our results highlight that self-organization promotes the efficiency and stability of complex ecosystems at extracting energy from the environment, even in the absence of any centralized coordination.", "date": "2023-12-26", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "120", "number": "52", "publisher": "National Academy of Sciences", "pagerange": "e2309387120", "issn": "0027-8424", "official_url": "https://authors.library.caltech.edu/records/zexft-t7k79", "funders": { "items": [ { "grant_number": "PHY-1748958" }, { "grant_number": "GBMF4513" }, { "grant_number": "61-1772" }, { "grant_number": "PHY-2317138" }, { "grant_number": "R35GM151211" }, { "grant_number": "PHY-2042150" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2309387120", "pmcid": "PMC10756307", "primary_object": { "basename": "goyal-et-al-2023-closed-ecosystems-extract-energy-through-self-organized-nutrient-cycles.pdf", "url": "https://authors.library.caltech.edu/records/zexft-t7k79/files/goyal-et-al-2023-closed-ecosystems-extract-energy-through-self-organized-nutrient-cycles.pdf" }, "related_objects": [ { "basename": "pnas.2309387120.sapp.pdf", "url": "https://authors.library.caltech.edu/records/zexft-t7k79/files/pnas.2309387120.sapp.pdf" } ], "pub_year": "2023", "author_list": "Goyal, Akshit; Flamholz, Avi I.; et al." }, { "id": "https://authors.library.caltech.edu/records/ve6kx-s2w29", "eprint_status": "archive", "datestamp": "2023-12-19 20:43:26", "lastmod": "2024-12-21 00:02:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Larsson-Henrik-R", "name": { "family": "Larsson", "given": "Henrik R." }, "orcid": "0000-0002-9417-1518" }, { "id": "Lee-Seunghoon", "name": { "family": "Lee", "given": "Seunghoon" }, "orcid": "0000-0003-3665-587X" }, { "id": "Cui-Zhi-Hao", "name": { "family": "Cui", "given": "Zhi-Hao" }, "orcid": "0000-0002-7389-4063" }, { "id": "Zhu-Tianyu", "name": { "family": "Zhu", "given": "Tianyu" }, "orcid": "0000-0003-2061-3237" }, { "id": "Sun-Chong", "name": { "family": "Sun", "given": "Chong" }, "orcid": "0000-0002-8299-9094" }, { "id": "Peng-Linqing", "name": { "family": "Peng", "given": "Linqing" }, "orcid": "0000-0001-5682-2407" }, { "id": "Peng-Ruojing", "name": { "family": "Peng", "given": "Ruojing" }, "orcid": "0000-0002-5293-7503" }, { "id": "Liao-Ke", "name": { "family": "Liao", "given": "Ke" }, "orcid": "0000-0002-3643-9141" }, { "id": "T\u00f6lle-Johannes", "name": { "family": "T\u00f6lle", "given": "Johannes" }, "orcid": "0000-0002-2414-7758" }, { "id": "Yang-Junjie", "name": { "family": "Yang", "given": "Junjie" }, "orcid": "0000-0002-6726-6538" }, { "id": "Li-Shuoxue", "name": { "family": "Li", "given": "Shuoxue" }, "orcid": "0000-0003-3428-0488" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Block2: A comprehensive open source framework to develop and apply state-of-the-art DMRG algorithms in electronic structure and beyond", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry; General Physics and Astronomy", "note": "

\u00a9 2023 Author(s). Published under an exclusive license by AIP Publishing.

\n\n

H.Z. thanks Sandeep Sharma for helpful discussions. This framework was produced over several years with contributions from multiple individuals. Work by H.Z. was supported by the U.S. National Science Foundation under Award No. CHE-2102505. Work by H.R.L. and T.Z. was supported by the Air Force Office of Scientific Research under Award No. FA9550-18-1-0095. H.R.L. acknowledges support from a postdoctoral fellowship from the German Research Foundation (DFG) via Grant No. LA 4442/1-1 during the first part of this work. Work by S.L. (this material) was supported by the U.S. Department of Energy, Office of Science, National Quantum Information Science Research Centers, Quantum Systems Accelerator. Work by Z.C. was supported by the U.S. Department of Energy, Office of Science, under Award No. DE-SC0018140. Work by C.S. was supported by the U.S. Department of Energy, Office of Science, under Grant No. DE-SC0019374. Work by L.P. was supported by the U.S. Department of Energy, Office of Science, via the M2QM EFRC under Grant No. DE-SC0019330. Work by R.P. was supported by the U.S. National Science Foundation under Award No. CHE-2102505. Work by K.L. was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences and Office of Advanced Scientific Computing Research, Scientific Discovery through Advanced Computing (SciDAC) program, under Award No. DE-SC0022088. Work by J.T. was supported by the U.S. Department of Energy, Office of Science, under Award No. DE-SC0018140. J.T. acknowledges funding through a postdoctoral research fellowship from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)\u2014Grant No. 495279997. Work by J.Y. was supported by the U.S. Department of Energy, Office of Science, via the M2QM EFRC under Grant No. DE-SC0019330. The computations presented in this work were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.

\n\n

Huanchen Zhai: Conceptualization (lead); Data curation (lead); Methodology (lead); Software (lead); Validation (lead); Writing \u2013 original draft (lead); Writing \u2013 review & editing (equal). Henrik R. Larsson: Methodology (equal); Software (equal); Validation (equal); Writing \u2013 review & editing (equal). Seunghoon Lee: Methodology (equal); Software (equal); Validation (equal); Writing \u2013 review & editing (equal). Zhi-Hao Cui: Methodology (equal); Software (equal); Validation (equal); Writing \u2013 review & editing (equal). Tianyu Zhu: Methodology (equal); Software (equal); Validation (equal); Writing \u2013 review & editing (equal). Chong Sun: Methodology (equal); Software (equal); Validation (equal); Writing \u2013 review & editing (equal). Linqing Peng: Software (supporting); Validation (equal); Writing \u2013 review & editing (equal). Ruojing Peng: Software (supporting); Validation (equal); Writing \u2013 review & editing (equal). Ke Liao: Software (supporting); Validation (equal); Writing \u2013 review & editing (equal). Johannes T\u00f6lle: Software (supporting); Validation (equal); Writing \u2013 review & editing (equal). Junjie Yang: Software (supporting); Validation (equal); Writing \u2013 review & editing (equal). Shuoxue Li: Software (supporting); Validation (equal); Writing \u2013 review & editing (equal). Garnet Kin-Lic Chan: Conceptualization (lead); Funding acquisition (lead); Methodology (lead); Project administration (lead); Supervision (lead); Writing \u2013 review & editing (lead).

\n\n

The reference input and output files for producing data in the numerical examples can be found in the GitHub repository https://github.com/hczhai/block2-example-data. The reference software version is block2 0.5.2.

\n\n

The authors have no conflicts to disclose.

", "abstract": "

BLOCK2 is an open source framework to implement and perform density matrix renormalization group and matrix product state algorithms. Out-of-the-box it supports the eigenstate, time-dependent, response, and finite-temperature algorithms. In addition, it carries special optimizations for ab initio electronic structure Hamiltonians and implements many quantum chemistry extensions to the density matrix renormalization group, such as dynamical correlation theories. The code is designed with an emphasis on flexibility, extensibility, and efficiency and to support integration with external numerical packages. Here, we explain the design principles and currently supported features and present numerical examples in a range of applications.

", "date": "2023-12-21", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "159", "number": "23", "publisher": "AIP Publishing", "pagerange": "234801", "issn": "0021-9606", "official_url": "https://authors.library.caltech.edu/records/ve6kx-s2w29", "funders": { "items": [ { "grant_number": "CHE-2102505" }, { "grant_number": "FA9550-18-1-0095" }, { "grant_number": "LA 4442/1-1" }, { "grant_number": "DE-SC0018140" }, { "grant_number": "DE-SC0019374" }, { "grant_number": "DE-SC0019330" }, { "grant_number": "DE-SC0022088" }, { "grant_number": "495279997" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/5.0180424", "primary_object": { "basename": "234801_1_5.0180424.pdf", "url": "https://authors.library.caltech.edu/records/ve6kx-s2w29/files/234801_1_5.0180424.pdf" }, "pub_year": "2023", "author_list": "Zhai, Huanchen; Larsson, Henrik R.; et al." }, { "id": "https://authors.library.caltech.edu/records/k6mgk-tsg52", "eprint_status": "archive", "datestamp": "2023-12-18 17:32:20", "lastmod": "2024-05-03 17:56:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Debnath-Ramit", "name": { "family": "Debnath", "given": "Ramit" }, "orcid": "0000-0003-0727-5683" }, { "id": "Ebanks-Daniel", "name": { "family": "Ebanks", "given": "Danny" }, "orcid": "0000-0001-5928-9396" }, { "id": "Mohaddes-Kamiar", "name": { "family": "Mohaddes", "given": "Kamiar" }, "orcid": "0000-0002-2501-2062" }, { "id": "Roulet-Thomas", "name": { "family": "Roulet", "given": "Thomas" }, "orcid": "0000-0002-9148-3743" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. Michael" }, "orcid": "0000-0002-8113-4451" } ] }, "title": "Do fossil fuel firms reframe online climate and sustainability communication? A data-driven analysis", "ispublished": "pub", "full_text_status": "public", "note": "

\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

\n\n

We thank Michael Ewens for his help accessing the CRSP data we use in this paper. RD's work is supported by the Quadrature Climate Foundation, 2023 Google Cloud Climate Innovation program and the Bill & Melinda Gates Foundation [OPP1144]. KM, TR, and RD acknowledges support from the Cambridge Judge Business School Small Grant Scheme [SG20-09] and Cambridge Faculty of Economics Keynes Fund [JHVH]. RMA and DE's work is supported by Caltech's Resnick Sustainability Institute (DE's work was supported by the Caltech Resnick Sustainability Institute while he was a PhD candidate at Caltech). RD is grateful to Professor Flora Samuel, Stan Finney and Zara Kuckelhaus for supporting with computing infrastructure.

\n\n

These authors contributed equally: Ramit Debnath, Danny Ebanks.

R.D.: Conceptualization, methodology, investigation, data curation, writing\u2014original draft, writing\u2014review & editing, project administration, funding acquisition, supervision. D.E.: Conceptualization, methodology, investigation, formal analysis, data curation, writing\u2014original draft, writing\u2014review & editing, project administration, visualization. K.M.: Conceptualization, funding acquisition. T.R.: Conceptualization, writing\u2014review & editing, funding acquisition. R.M.A.: Conceptualization, methodology, investigation, writing original draft, writing\u2014review & editing, project administration, funding acquisition, supervision.

\n\n

The materials necessary to reproduce the results reported in this paper are available at https://github.com/danielEban ks/. Energy-Industry-Greenwashing. Per the terms of Twitter's academic use policies, we will make available the tweet IDs for the data used in this paper upon publication. Researchers can obtain the CRSP data from https://www.crsp.org/. Publicly available extreme weather events data can be obtained from EM-DAT (https://www.emdat.be). Alternatively, please contact the corresponding author to request the dataset.

\n\n

The code necessary to reproduce the results reported in this paper is available at the following GitHub repository: https://github.com/danielEbanks/Energy-Industry-Greenwashing.

\n\n

The authors declare no competing interests.

", "abstract": "

Identifying drivers of climate misinformation on social media is crucial to climate action. Misinformation comes in various forms; however, subtler strategies, such as emphasizing favorable interpretations of events or data or reframing conversations to fit preferred narratives, have received little attention. This data-driven paper examines online climate and sustainability communication behavior over 7 years (2014\u20132021) across three influential stakeholder groups consisting of eight fossil fuel firms (industry), 14 non-governmental organizations (NGOs), and eight inter-governmental organizations (IGOs). We examine historical Twitter interaction data (n\u2009=\u2009668,826) using machine learning-driven joint-sentiment topic modeling and vector autoregression to measure online interactions and influences amongst these groups. We report three key findings. First, we find that the stakeholders in our sample are responsive to one another online, especially over topics in their respective areas of domain expertise. Second, the industry is more likely to respond to IGOs' and NGOs' online messaging changes, especially regarding environmental justice and climate action topics. The fossil fuel industry is more likely to discuss public relations, advertising, and corporate sustainability topics. Third, we find that climate change-driven extreme weather events and stock market performance do not significantly affect the patterns of communication among these firms and organizations. In conclusion, we provide a data-driven foundation for understanding the influence of powerful stakeholder groups on shaping the online climate and sustainability information ecosystem around climate change.

", "date": "2023-12-18", "date_type": "published", "publication": "npj Climate Action", "volume": "2", "publisher": "Nature Publishing Group", "pagerange": "47", "issn": "2731-9814", "official_url": "https://authors.library.caltech.edu/records/k6mgk-tsg52", "funders": { "items": [ {}, { "grant_number": "OPP1144" }, { "grant_number": "SG20-09" }, { "grant_number": "Keynes Fund" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s44168-023-00086-x", "pmcid": "PMC11062293", "primary_object": { "basename": "s44168-023-00086-x.pdf", "url": "https://authors.library.caltech.edu/records/k6mgk-tsg52/files/s44168-023-00086-x.pdf" }, "related_objects": [ { "basename": "44168_2023_86_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/k6mgk-tsg52/files/44168_2023_86_MOESM2_ESM.pdf" } ], "pub_year": "2023", "author_list": "Debnath, Ramit; Ebanks, Danny; et al." }, { "id": "https://authors.library.caltech.edu/records/8z9fy-q2405", "eprint_status": "archive", "datestamp": "2023-12-08 22:04:44", "lastmod": "2025-11-22 02:01:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Du-Yufeng", "name": { "family": "Du", "given": "Yufeng" }, "orcid": "0000-0003-0510-5170" }, { "id": "Lee-Vincent-S-H", "name": { "family": "Lee", "given": "Vincent S.\u2009H." }, "orcid": "0000-0002-3481-3590" }, { "id": "Wang-Yikun", "name": { "family": "Wang", "given": "Yikun" } }, { "id": "Zurek-K-M", "name": { "family": "Zurek", "given": "Kathryn M." }, "orcid": "0000-0002-2629-337X" } ] }, "title": "Macroscopic dark matter detection with gravitational wave experiments", "ispublished": "pub", "full_text_status": "public", "note": "

\u00a9 2023 American Physical Society.

\n\n

We thank Sebastian Baum, Mathew Bub, Yanbei Chen, Michael Fedderke, Moira Gresham, Dongjun Li, Clara Murgui, Kris Pardo, and Yiwen Zhang for helpful discussions on related topics. This work is supported by the Quantum Information Science Enabled Discovery (QuantISED) for High Energy Physics (KA2401032), the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award No. DE-SC0011632, and by the Walter Burke Institute for Theoretical Physics. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.

", "abstract": "

We study signatures of macroscopic dark matter (DM) in current and future gravitational wave (GW) experiments. Transiting DM with a mass of \u223c10\u2075\u201310\u00b9\u2075\u2009\u2009kg that saturates the local DM density can be potentially detectable by GW detectors, depending on the baseline of the detector and the strength of the force mediating the interaction. In the context of laser interferometers, we derive the gauge invariant observable due to a transiting DM, including the Shapiro effect (gravitational time delay accumulated during the photon propagation), and adequately account for the finite photon travel time within an interferometer arm. In particular, we find that the Shapiro effect can be dominant for short-baseline interferometers such as Holometer and GQuEST. We also find that proposed experiments such as Cosmic Explorer and Einstein Telescope can constrain a fifth force between DM and baryons, at the level of strength \u223c10\u00b3 times stronger than gravity for, e.g., kg mass DM with a fifth-force range of 10\u2076\u2009\u2009m.

", "date": "2023-12-15", "date_type": "published", "publication": "Physical Review D", "volume": "108", "number": "12", "publisher": "American Physical Society", "pagerange": "122003", "issn": "2470-0010", "official_url": "https://authors.library.caltech.edu/records/8z9fy-q2405", "funders": { "items": [ { "grant_number": "DE-SC0011632" }, { "agency": "Walter Burke Institute for Theoretical Physics" }, {} ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevd.108.122003", "primary_object": { "basename": "PhysRevD.108.122003.pdf", "url": "https://authors.library.caltech.edu/records/8z9fy-q2405/files/PhysRevD.108.122003.pdf" }, "pub_year": "2023", "author_list": "Du, Yufeng; Lee, Vincent S.\u2009H.; et al." }, { "id": "https://authors.library.caltech.edu/records/q97z6-5ta27", "eprint_status": "archive", "datestamp": "2023-11-21 20:56:46", "lastmod": "2023-12-21 21:40:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Rosa-Lorenzo", "name": { "family": "Rosa", "given": "Lorenzo" }, "orcid": "0000-0002-1280-9945" }, { "id": "Lobell-David-B", "name": { "family": "Lobell", "given": "David B." }, "orcid": "0000-0002-5969-3476" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" } }, { "id": "Yin-Yi", "name": { "family": "Yin", "given": "Yi" }, "orcid": "0000-0003-4750-4997" }, { "id": "Doughty-Russell", "name": { "family": "Doughty", "given": "Russell" }, "orcid": "0000-0001-5191-2155" }, { "id": "Yao-Yitong", "name": { "family": "Yao", "given": "Yitong" }, "orcid": "0000-0002-1713-6719" }, { "id": "Berry-Joseph-A", "name": { "family": "Berry", "given": "Joseph A." }, "orcid": "0000-0002-5849-6438" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "The weekly cycle of photosynthesis in Europe reveals the negative impact of particulate pollution on ecosystem productivity", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

\u00a9 2023 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).

\n\n

This work was supported by the Carnegie Institution for Science. L.H. was partially supported by the fellowship from Resnick Sustainability Institute at California Institute of Technology. Y. Yin and C.F. were supported by the NASA OCO2/3 science team (Grant 80NSSC18K0895). Y.W. was supported by the NSF grant (Award No. AGS-2103714). We thank Drs. Wu Sun (Carnegie Institution for Science), Yujie Wang (California Institute of Technology), and Xinchen Lu (University of California, Berkeley) for helpful discussions.

\n\n

L.H. and D.B.L. conceived the study; L.H., L.R., D.B.L., and C.F. designed the study; L.H. and R.D. collected data; L.H. performed data analysis and wrote the paper; Y.W., Y. Yin, and J.A.B. contributed the discussion of method development; L.H. led the interpretation of the results with input from L.R., D.B.L., Y.W., Y. Yin, Y. Yao, J.A.B., and C.F.; and all authors provided feedback on the manuscript.

\n\n

The TROPOMI SIF product can be accessed at https://climatesciences.jpl.nasa.gov/sif/download-data/level-2/ (34). Hourly meteorological data from ERA5 is publicly available through the Copernicus Climate Change Service (https://cds.climate.copernicus.eu/cdsapp#!/dataset/reanalysis-era5-single-levels?tab=form) (78). VIIRS EPS AOD data can be downloaded from https://www.star.nesdis.noaa.gov/pub/smcd/VIIRS_Aerosol/viirs_aerosol_gridded_data/ (79). The MODIS MCD12Q1 v006 landcover data are available at https://lpdaac.usgs.gov/products/mcd12q1v006/ (80). Additionally, the MODIS MOD15A2H v006 fPAR data can be found at https://lpdaac.usgs.gov/products/mod15a2hv006/ (81). The MODIS MCD18C2 v061 PAR data are available at https://lpdaac.usgs.gov/products/mcd18c2v061/ (82). FLUXCOM GPP and NEE are available at https://www.fluxcom.org/CF-Download/ (76). TROPOMI NO2 can be downloaded from http://www.tropomi.eu/data-products/nitrogen-dioxide (83). MODIS cloud optical thickness is available at https://ladsweb.modaps.eosdis.nasa.gov/missions-and-measurements/products/MCD06COSP_D3_MODIS (84). The eddy covariance measurements are obtained from the ICOS (https://meta.icos-cp.eu/collections/-ZrCo_Cousoqvxnlvz83l0K4) (72). The SEM analysis is carried out using the \"semopy\" package in Python. The regression analysis is conducted by \"statsmodels\" package in Python. All other data are included in the manuscript and/or SI Appendix.

\n\n

The authors declare no competing interest.

", "abstract": "

Aerosols can affect photosynthesis through radiative perturbations such as scattering and absorbing solar radiation. This biophysical impact has been widely studied using field measurements, but the sign and magnitude at continental scales remain uncertain. Solar-induced fluorescence (SIF), emitted by chlorophyll, strongly correlates with photosynthesis. With recent advancements in Earth observation satellites, we leverage SIF observations from the Tropospheric Monitoring Instrument (TROPOMI) with unprecedented spatial resolution and near-daily global coverage, to investigate the impact of aerosols on photosynthesis. Our analysis reveals that on weekends when there is more plant-available sunlight due to less particulate pollution, 64% of regions across Europe show increased SIF, indicating more photosynthesis. Moreover, we find a widespread negative relationship between SIF and aerosol loading across Europe. This suggests the possible reduction in photosynthesis as aerosol levels increase, particularly in ecosystems limited by light availability. By considering two plausible scenarios of improved air quality\u2014reducing aerosol levels to the weekly minimum 3-d values and levels observed during the COVID-19 period\u2014we estimate a potential of 41 to 50 Mt net additional annual CO\u2082 uptake by terrestrial ecosystems in Europe. This work assesses human impacts on photosynthesis via aerosol pollution at continental scales using satellite observations. Our results highlight i) the use of spatiotemporal variations in satellite SIF to estimate the human impacts on photosynthesis and ii) the potential of reducing particulate pollution to enhance ecosystem productivity.

", "date": "2023-12-05", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "120", "number": "49", "publisher": "National Academy of Sciences", "pagerange": "e2306507120", "issn": "0027-8424", "official_url": "https://authors.library.caltech.edu/records/q97z6-5ta27", "funders": { "items": [ {}, { "grant_number": "Resnick Sustainability Institute" }, { "grant_number": "80NSSC18K0895" }, { "grant_number": "AGS-2103714" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2306507120", "pmcid": "PMC10710040", "primary_object": { "basename": "he-et-al-2023-the-weekly-cycle-of-photosynthesis-in-europe-reveals-the-negative-impact-of-particulate-pollution-on.pdf", "url": "https://authors.library.caltech.edu/records/q97z6-5ta27/files/he-et-al-2023-the-weekly-cycle-of-photosynthesis-in-europe-reveals-the-negative-impact-of-particulate-pollution-on.pdf" }, "related_objects": [ { "basename": "pnas.2306507120.sapp.pdf", "url": "https://authors.library.caltech.edu/records/q97z6-5ta27/files/pnas.2306507120.sapp.pdf" } ], "pub_year": "2023", "author_list": "He, Liyin; Rosa, Lorenzo; et al." }, { "id": "https://authors.library.caltech.edu/records/hnnwr-z0490", "eprint_status": "archive", "datestamp": "2023-12-13 18:43:11", "lastmod": "2023-12-13 18:43:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulze-Benjamin-C", "name": { "family": "Schulze", "given": "Benjamin C." }, "orcid": "0000-0002-6405-8872" }, { "id": "Ward-Ryan-X", "name": { "family": "Ward", "given": "Ryan X." }, "orcid": "0000-0003-2317-3310" }, { "id": "Pfannerstill-Eva-Y", "name": { "family": "Pfannerstill", "given": "Eva Y." }, "orcid": "0000-0001-7715-1200" }, { "id": "Zhu-Qindan", "name": { "family": "Zhu", "given": "Qindan" }, "orcid": "0000-0003-2173-4014" }, { "id": "Arata-Caleb", "name": { "family": "Arata", "given": "Caleb" }, "orcid": "0000-0002-0170-8794" }, { "id": "Place-Bryan-K", "name": { "family": "Place", "given": "Bryan" }, "orcid": "0000-0002-9224-2837" }, { "id": "Nussbaumer-Clara", "name": { "family": "Nussbaumer", "given": "Clara" }, "orcid": "0000-0002-5662-8476" }, { "id": "Wooldridge-Paul", "name": { "family": "Wooldridge", "given": "Paul" }, "orcid": "0000-0003-2711-5900" }, { "id": "Woods-Roy", "name": { "family": "Woods", "given": "Roy" }, "orcid": "0000-0002-3632-6374" }, { "id": "Bucholtz-Anthony", "name": { "family": "Bucholtz", "given": "Anthony" } }, { "id": "Cohen-Ronald-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Goldstein-Allen-H", "name": { "family": "Goldstein", "given": "Allen H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Methane Emissions from Dairy Operations in California's San Joaquin Valley Evaluated Using Airborne Flux Measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "Environmental Chemistry; General Chemistry", "note": "

\u00a9 2023 American Chemical Society.

\n\n

We would like to thank Greg Cooper, Bryce Kujat, and George Loudakis for their dedicated mission support during RECAP-CA. We would also like to thank Timothy Lueker, Jooil Kim, and Ralph Keeling for assistance with the Picarro G2401-m calibrations at the Scripps Institution of Oceanography. This research was funded by the following sources: California Air Resources Board Contract numbers 20RD003 and 20AQP012, NOAA Climate Program Office's Atmospheric Chemistry, Carbon Cycle, and Climate program, grant number NA22OAR4310540 [UCB]/NA22OAR4310541 [AD], Office of Naval Research Defense University Research Instrumentation Program grant number N00014-19-1-2108. We thank the Resnick Sustainability Institute at Caltech for funding the purchase of the Picarro G2401-m.

\n\n

The authors declare no competing financial interest.

", "abstract": "

State inventories indicate that dairy operations account for nearly half of California's methane budget. Recent analyses suggest, however, that these emissions may be underestimated, complicating efforts to develop emission reduction strategies. Here, we report estimates of dairy methane emissions in the southern San Joaquin Valley (SJV) of California in June 2021 using airborne flux measurements. We find average dairy methane fluxes of 512 \u00b1 178 mg m\u207b\u00b2 h\u207b\u00b9 from a region of 300+ dairies near Visalia, CA using a combination of eddy covariance and mass balance-based techniques, corresponding to 118 \u00b1 41 kg dairy\u207b\u00b9 h\u207b\u00b9. These values estimated during our June campaign are 39 \u00b1 48% larger than annual average estimates from the recently developed VISTA-CA inventory. We observed notable increases in emissions with temperature. Our estimates align well with inventory predictions when parametrizations for the temperature dependence of emissions are applied. Our measurements further demonstrate that the VISTA-CA emission inventory is considerably more accurate than the EPA GHG-I inventory in this region. Source apportionment analyses confirm that dairy operations produce the majority of methane emissions in the southern SJV (\u223c65%). Fugitive oil and gas (O&G) sources account for the remaining \u223c35%. Our results support the accuracy of the process-based models used to develop dairy emission inventories and highlight the need for additional investigation of the meteorological dependence of these emissions.

 

", "date": "2023-12-05", "date_type": "published", "publication": "Environmental Science & Technology", "volume": "57", "number": "48", "publisher": "American Chemical Society", "pagerange": "19519-19531", "issn": "0013-936X", "official_url": "https://authors.library.caltech.edu/records/hnnwr-z0490", "funders": { "items": [ { "grant_number": "20RD003" }, { "grant_number": "20AQP012" }, { "grant_number": "NA22OAR4310540" }, { "grant_number": "NA22OAR4310541" }, { "grant_number": "N00014-19-1-2108" }, { "grant_number": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.est.3c03940", "primary_object": { "basename": "es3c03940_si_001.pdf", "url": "https://authors.library.caltech.edu/records/hnnwr-z0490/files/es3c03940_si_001.pdf" }, "pub_year": "2023", "author_list": "Schulze, Benjamin C.; Ward, Ryan X.; et al." }, { "id": "https://authors.library.caltech.edu/records/gh23d-w3v33", "eprint_status": "archive", "datestamp": "2023-12-04 21:59:47", "lastmod": "2023-12-04 21:59:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Yide", "name": { "family": "Zhang", "given": "Yide" }, "orcid": "0000-0002-9463-3970" }, { "id": "Hu-Peng", "name": { "family": "Hu", "given": "Peng" }, "orcid": "0000-0002-2933-1239" }, { "id": "Li-Lei", "name": { "family": "Li", "given": "Lei" } }, { "id": "Cao-Rui", "name": { "family": "Cao", "given": "Rui" }, "orcid": "0000-0003-4444-7528" }, { "id": "Khadria-Anjul", "name": { "family": "Khadria", "given": "Anjul" }, "orcid": "0000-0002-9771-3650" }, { "id": "Maslov-Konstantin", "name": { "family": "Maslov", "given": "Konstantin" }, "orcid": "0000-0003-3408-8840" }, { "id": "Tong-Xin", "name": { "family": "Tong", "given": "Xin" } }, { "id": "Zeng-Yushun", "name": { "family": "Zeng", "given": "Yushun" }, "orcid": "0000-0001-5995-4085" }, { "id": "Jiang-Laiming", "name": { "family": "Jiang", "given": "Laiming" }, "orcid": "0000-0002-8658-3168" }, { "id": "Zhou-Qifa", "name": { "family": "Zhou", "given": "Qifa" }, "orcid": "0000-0003-1527-3020" }, { "id": "Wang-Lihong-V", "name": { "family": "Wang", "given": "Lihong V." }, "orcid": "0000-0001-9783-4383" } ] }, "title": "Ultrafast longitudinal imaging of haemodynamics via single-shot volumetric photoacoustic tomography with a single-element detector", "ispublished": "pub", "full_text_status": "public", "keywords": "Computer Science Applications; Biomedical Engineering; Medicine (miscellaneous); Bioengineering; Biotechnology", "note": "

\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2023.

\n\n

These authors contributed equally: Yide Zhang, Peng Hu.

Y. Zhang and L.V.W. conceived and designed the study. Y. Zhang, L.L., R.C. and K.M. built the imaging system. Y. Zhang developed the data acquisition program. P.H. developed the 3D reconstruction algorithm. Y. Zhang, L.L., R.C. and A.K. performed the experiments. Y. Zhang, P.H. and X.T. processed and analysed the data. Y. Zeng, L.J. and Q.Z. fabricated the ultrasonic transducer. L.V.W. supervised the study. All of the authors contributed to writing the paper.

\n\n

The data supporting the findings of this study are provided within the Article and its Supplementary Information. The raw and analysed datasets generated during the study are available for research purposes from the corresponding authors on reasonable request.

\n\n

The reconstruction code, the system-control software and the data-collection software are proprietary and used in licensed technologies, yet they are available from the corresponding author on reasonable request.

\n\n

L.V.W. has a financial interest in Microphotoacoustics, CalPACT and Union Photoacoustic Technologies. These companies did not provide support for this work. K.M. has a financial interest in Microphotoacoustics. All other authors declare no competing interests.

", "abstract": "

We thank Y. Zhao for contributing to the universal calibration. This work was supported in part by National Institutes of Health grants R01 EB028277, U01 EB029823 and R35 CA220436 (Outstanding Investigator Award). The computations presented here were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.

", "date": "2023-11-30", "date_type": "published", "publication": "Nature Biomedical Engineering", "publisher": "Nature Publishing Group", "issn": "2157-846X", "official_url": "https://authors.library.caltech.edu/records/gh23d-w3v33", "funders": { "items": [ { "grant_number": "R01 EB028277" }, { "grant_number": "U01 EB029823" }, { "grant_number": "R35 CA220436" }, { "grant_number": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41551-023-01149-4", "primary_object": { "basename": "41551_2023_1149_Fig7_ESM.jpg", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_Fig7_ESM.jpg" }, "related_objects": [ { "basename": "41551_2023_1149_MOESM5_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM5_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM6_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM6_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM8_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM8_ESM.mp4" }, { "basename": "41551_2023_1149_Fig9_ESM.jpg", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_Fig9_ESM.jpg" }, { "basename": "41551_2023_1149_MOESM10_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM10_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM15_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM15_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM17_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM17_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM7_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM7_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM13_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM13_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM1_ESM.pdf" }, { "basename": "41551_2023_1149_MOESM4_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM4_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM9_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM9_ESM.mp4" }, { "basename": "41551_2023_1149_Fig10_ESM.jpg", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_Fig10_ESM.jpg" }, { "basename": "41551_2023_1149_Fig8_ESM.jpg", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_Fig8_ESM.jpg" }, { "basename": "41551_2023_1149_MOESM11_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM11_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM12_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM12_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM14_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM14_ESM.mp4" }, { "basename": "41551_2023_1149_MOESM16_ESM.mp4", "url": "https://authors.library.caltech.edu/records/gh23d-w3v33/files/41551_2023_1149_MOESM16_ESM.mp4" } ], "pub_year": "2023", "author_list": "Zhang, Yide; Hu, Peng; et al." }, { "id": "https://authors.library.caltech.edu/records/p74yx-zq547", "eprint_status": "archive", "datestamp": "2023-12-06 18:19:41", "lastmod": "2025-11-21 22:40:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Lee-Seunghoon", "name": { "family": "Lee", "given": "Seunghoon" }, "orcid": "0000-0003-3665-587X" }, { "id": "Cui-Zhi-Hao", "name": { "family": "Cui", "given": "Zhi-Hao" }, "orcid": "0000-0002-7389-4063" }, { "id": "Cao-Lili", "name": { "family": "Cao", "given": "Lili" } }, { "id": "Ryde-Ulf", "name": { "family": "Ryde", "given": "Ulf" }, "orcid": "0000-0001-7653-8489" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Multireference Protonation Energetics of a Dimeric Model of Nitrogenase Iron\u2013Sulfur Clusters", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry", "note": "

\u00a9 2023 The Authors. Published by American Chemical Society. Permits the broadest form of re-use including for commercial purposes, provided that author attribution and integrity are maintained (https://creativecommons.org/licenses/by/4.0/).

\n\n

Work at Caltech was supported by the Center for Molecular Magnetic Quantum Materials, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award DE-SC0019330. The computations were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. Work at Lund University was supported by grants from the Swedish Research Council (Projects 2018-05003 and 2022-04978). The computations were performed on computer resources provided by the Swedish National Infrastructure for Computing (SNIC) at Lunarc at Lund University and HPC2N at Ume\u00e5 University, partially funded by the Swedish Research Council (Grant 2018-05973).

\n\n

The authors declare no competing financial interest.
 

 

", "abstract": "

Characterizing the electronic structure of the iron\u2013sulfur clusters in nitrogenase is necessary to understand their role in the nitrogen fixation process. One challenging task is to determine the protonation state of the intermediates in the nitrogen fixing cycle. Here, we use a dimeric iron\u2013sulfur model to study relative energies of protonation at C, S, or Fe. Using a composite method based on coupled cluster and density matrix renormalization group energetics, we converge the relative energies of four protonated configurations with respect to basis set and correlation level. We find that accurate relative energies require large basis sets as well as a proper treatment of multireference and relativistic effects. We have also tested ten density functional approximations for these systems. Most of them give large errors in their relative energies. The best performing functional in this system is B3LYP, which gives mean absolute and maximum deviations of only 10 and 13 kJ/mol with respect to our correlated wave function estimates, respectively, comparable to the uncertainty in our correlated estimates. Our work provides benchmark results for the calibration of new approximate electronic structure methods and density functionals for these problems.

", "date": "2023-11-30", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "127", "number": "47", "publisher": "American Chemical Society", "pagerange": "9974-9984", "issn": "1089-5639", "official_url": "https://authors.library.caltech.edu/records/p74yx-zq547", "funders": { "items": [ { "grant_number": "DE-SC0019330" }, { "grant_number": "2018-05003" }, { "grant_number": "2022-04978" }, { "grant_number": "2018-05973" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpca.3c06142", "pmcid": "PMC10694817", "primary_object": { "basename": "jp3c06142.pdf", "url": "https://authors.library.caltech.edu/records/p74yx-zq547/files/jp3c06142.pdf" }, "related_objects": [ { "basename": "jp3c06142_si_001.pdf", "url": "https://authors.library.caltech.edu/records/p74yx-zq547/files/jp3c06142_si_001.pdf" } ], "pub_year": "2023", "author_list": "Zhai, Huanchen; Lee, Seunghoon; et al." }, { "id": "https://authors.library.caltech.edu/records/wses6-86c89", "eprint_id": 120075, "eprint_status": "archive", "datestamp": "2023-12-04 17:49:00", "lastmod": "2025-09-26 23:07:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McBeath-Sean-T", "name": { "family": "McBeath", "given": "Sean T." }, "orcid": "0000-0003-0701-1645" }, { "id": "Zhang-Yi", "name": { "family": "Zhang", "given": "Yi" }, "orcid": "0000-0002-9062-5201" }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" } ] }, "title": "Novel Synthesis Pathways for Highly Oxidative Iron Species: Generation, Stability, and Treatment Applications of Ferrate(IV/V/VI)", "ispublished": "pub", "full_text_status": "public", "keywords": "Environmental Chemistry; General Chemistry", "note": "

\u00a9 2023 The Authors. Published by American Chemical Society. Attribution 4.0 International (CC BY 4.0). 

\n\n

This research was supported by the Resnick Sustainability Institute (RSI) Impact Grant. The authors would also like to thank Heng Dong for help with the Raman spectroscopy work, and Carl K. McBeath for help with the graphical abstract illustration.

\n\n

Co-first authors: S.T.M. and Y.Z. contributed equally to this paper.

\n\n

The authors declare no competing financial interest.

", "abstract": "Difficulties arise related to the economy-of-scale and practicability in applying conventional water treatment technologies to small and remote systems. A promising oxidation technology better suited for these applications is that of electro-oxidation (EO), whereby contaminants are degraded via direct, advanced, and/or electrosynthesized oxidant-mediated reactions. One species of oxidants of particular interest includes ferrates (Fe(VI)/(V)/(IV)), where only recently has their circumneutral synthesis been demonstrated, using high oxygen overpotential (HOP) electrodes, namely boron-doped diamond (BDD). In this study, the generation of ferrates using various HOP electrodes (BDD, NAT/Ni\u2013Sb\u2013SnO\u2082, and AT/Sb-SnO\u2082) was investigated. Ferrate synthesis was pursued in a current density range of 5\u201315 mA cm\u207b\u00b2 and initial Fe\u00b3\u207a concentrations of 10\u201315 mM. Faradaic efficiencies ranged from 11\u201323%, depending on operating conditions, with BDD and NAT significantly outperforming AT electrodes. Speciation tests revealed that NAT synthesizes both ferrate(IV/V) and ferrate(VI), while the BDD and AT electrodes synthesized only ferrate(IV/V) species. A number of organic scavenger probes were used to test the relative reactivity, including nitrobenzene, carbamazepine, and fluconazole, whereby ferrate(IV/V) was significantly more oxidative than ferrate(VI). Finally, the ferrate(VI) synthesis mechanism by NAT electrolysis was elucidated, where coproduction of ozone was found to be a key phenomenon for Fe\u00b3\u207a oxidation to ferrate(VI).", "date": "2023-11-28", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "57", "number": "47", "publisher": "American Chemical Society", "pagerange": "18700-18709", "id_number": "CaltechAUTHORS:20230315-645491100.7", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230315-645491100.7", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Engineering-and-Applied-Science" } ] }, "doi": "10.1021/acs.est.2c09237", "pmcid": "PMC10690715", "primary_object": { "basename": "es2c09237.pdf", "url": "https://authors.library.caltech.edu/records/wses6-86c89/files/es2c09237.pdf" }, "related_objects": [ { "basename": "es2c09237_si_001.pdf", "url": "https://authors.library.caltech.edu/records/wses6-86c89/files/es2c09237_si_001.pdf" } ], "pub_year": "2023", "author_list": "McBeath, Sean T.; Zhang, Yi; et al." }, { "id": "https://authors.library.caltech.edu/records/7sk0g-48t54", "eprint_status": "archive", "datestamp": "2024-05-03 16:40:38", "lastmod": "2025-10-24 22:37:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kemeny-Preston-Cosslett", "name": { "family": "Kemeny", "given": "Preston Cosslett" }, "orcid": "0000-0003-1693-4142" }, { "id": "Li-Gen-K", "name": { "family": "Li", "given": "Gen K." }, "orcid": "0000-0002-6300-3570" }, { "id": "Douglas-Madison", "name": { "family": "Douglas", "given": "Madison" }, "orcid": "0000-0002-0762-4719" }, { "id": "Berelson-William", "name": { "family": "Berelson", "given": "William" }, "orcid": "0000-0002-1526-3802" }, { "id": "Chadwick-Austin-J", "name": { "family": "Chadwick", "given": "Austin J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Dalleska-Nathan-F", "name": { "family": "Dalleska", "given": "Nathan F." }, "orcid": "0000-0002-2059-1587" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" }, { "id": "Larsen-William", "name": { "family": "Larsen", "given": "William" }, "orcid": "0000-0003-2001-9860" }, { "id": "Magyar-John-S", "name": { "family": "Magyar", "given": "John S." }, "orcid": "0000-0002-3586-8286" }, { "id": "Rollins-Nick-E", "name": { "family": "Rollins", "given": "Nick E." } }, { "id": "Rowland-Joel", "name": { "family": "Rowland", "given": "Joel" }, "orcid": "0000-0001-6308-8976" }, { "id": "Smith-M-Isabel", "name": { "family": "Smith", "given": "M. Isabel" }, "orcid": "0009-0002-9170-7222" }, { "id": "Torres-Mark-A", "name": { "family": "Torres", "given": "Mark A." }, "orcid": "0000-0002-9599-2748" }, { "id": "Webb-Samuel-M", "name": { "family": "Webb", "given": "Samuel M." }, "orcid": "0000-0003-1188-0464" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "West-A-Joshua", "name": { "family": "West", "given": "A. Joshua" }, "orcid": "0000-0001-6909-1471" } ] }, "title": "Arctic Permafrost Thawing Enhances Sulfide Oxidation", "ispublished": "pub", "full_text_status": "public", "note": "

© 2023. The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

\n\n
\n

This research took place on the lands of the Koyukuk-hotana Athabascans and we are grateful to the Huslia Tribal Council for permitting field access. PCK was supported during this work by the Cohan-Jacobs and Stein Families Fellowship from the Fannie and John Hertz Foundation. This research was also conducted with government support under and awarded by DoD, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a, to PCK and MD. We acknowledge support from Foster and Coco Stanback, the Linde Family, the Caltech Terrestrial Hazards Observation and Reporting (THOR) Center, NSF Award 2127442 to MPL and WWF, NSF award 2127444 to AJW, and the Caltech Resnick Sustainability Institute to MPL and WWF. We also acknowledge financial support from the Department of Energy (DOE) Office of Science, Biological and Environmental Research (BER), Earth and Environmental Systems Sciences Division (EESSD), Subsurface Biogeochemical Research Program Early Career Award to JCR. Support was also provided by Interdisciplinary Research for Arctic Coastal Environments (InteRFACE) project through the DOE BER EESSD Regional and Global Model Analysis program. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, was supported under Contract No. DE-AC02-76SF00515 by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, and we acknowledge the Polar Geospatial Center for providing a digital elevation model through NSF awards 1043681, 1559691, and 1542736. We thank S. Huffman, A. Attla, and V. Umphenour for assistance in the field, A. Sessions, F. Wu, and A. Phillips for assistance with EA-IRMS measurements, E. Eitel, S. Bone, N. Edwards, C. Roach, and J. Richardson for assistance with synchrotron measurements, G. Lopez for assistance with MC-ICP-MS measurements, X. Zhang and D. Dettman for measuring the oxygen isotope ratio of sulfate, and the AMS facility at the University of Arizona for measuring dissolved organic carbon isotope ratios. S. Tank and one anonymous reviewer provided insightful critiques on an earlier draft of this article, and the analysis benefited from discussions with J. Adkins.

\n
\n\n
\n
\n\n\n

All chemical observations are available as supplementary materials. The MEANDIR inversion model used in this manuscript is archived with Zenodo (Kemeny, 2023) and new editions will be released through GitHub (https://github.com/PrestonCosslettKemeny/MEANDIR). USGS data was downloaded from the National Water Information System or digitized from reports.

\n\n
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\n\n\n\n
Supporting information S1
\n
Data Set S1
\n\n

The authors declare no conflicts of interest relevant to this study.

", "abstract": "

Permafrost degradation is altering biogeochemical processes throughout the Arctic. Thaw-induced changes in organic matter transformations and mineral weathering reactions are impacting fluxes of inorganic carbon (IC) and alkalinity (ALK) in Arctic rivers. However, the net impact of these changing fluxes on the concentration of carbon dioxide in the atmosphere (pCO2) is relatively unconstrained. Resolving this uncertainty is important as thaw-driven changes in the fluxes of IC and ALK could produce feedbacks in the global carbon cycle. Enhanced production of sulfuric acid through sulfide oxidation is particularly poorly quantified despite its potential to remove ALK from the ocean-atmosphere system and increase pCO2, producing a positive feedback leading to more warming and permafrost degradation. In this work, we quantified weathering in the Koyukuk River, a major tributary of the Yukon River draining discontinuous permafrost in central Alaska, based on water and sediment samples collected near the village of Huslia in summer 2018. Using measurements of major ion abundances and sulfate (SO\u2084²\u207b) sulfur (34S/32S) and oxygen (18O/16O) isotope ratios, we employed the MEANDIR inversion model to quantify the relative importance of a suite of weathering processes and their net impact on pCO2. Calculations found that approximately 80% of SO4²\u207b in mainstem samples derived from sulfide oxidation with the remainder from evaporite dissolution. Moreover, 34S/32S ratios, 13C/12C ratios of dissolved IC, and sulfur X-ray absorption spectra of mainstem, secondary channel, and floodplain pore fluid and sediment samples revealed modest degrees of microbial sulfate reduction within the floodplain. Weathering fluxes of ALK and IC result in lower values of pCO2 over timescales shorter than carbonate compensation (∼104 yr) and, for mainstem samples, higher values of pCO2 over timescales longer than carbonate compensation but shorter than the residence time of marine SO\u2084²\u207b (∼107 yr). Furthermore, the absolute concentrations of SO\u2084²\u207b and Mg2+ in the Koyukuk River, as well as the ratios of SO\u2084²\u207b and Mg2+ to other dissolved weathering products, have increased over the past 50 years. Through analogy to similar trends in the Yukon River, we interpret these changes as reflecting enhanced sulfide oxidation due to ongoing exposure of previously frozen sediment and changes in the contributions of shallow and deep flow paths to the active channel. Overall, these findings confirm that sulfide oxidation is a substantial outcome of permafrost degradation and that the sulfur cycle responds to permafrost thaw with a timescale-dependent feedback on warming.

", "date": "2023-11", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "37", "number": "11", "publisher": "American Geophysical Union", "pagerange": "e2022GB007644", "issn": "0886-6236", "official_url": "https://authors.library.caltech.edu/records/7sk0g-48t54", "funders": { "items": [ {}, { "grant_number": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "grant_number": "Caltech Terrestrial Hazards Observation and Reporting (THOR) Center" }, { "grant_number": "RISE-2127442" }, { "grant_number": "RISE-2127444" }, {}, { "grant_number": "DE-AC02-76SF00515" }, { "grant_number": "OPP-1043681" }, { "grant_number": "OPP-1559691" }, { "grant_number": "OPP-1542736" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2022gb007644", "primary_object": { "basename": "Global Biogeochemical Cycles - 2023 - Kemeny - Arctic Permafrost Thawing Enhances Sulfide Oxidation.pdf", "url": "https://authors.library.caltech.edu/records/7sk0g-48t54/files/Global Biogeochemical Cycles - 2023 - Kemeny - Arctic Permafrost Thawing Enhances Sulfide Oxidation.pdf" }, "related_objects": [ { "basename": "2022gb007644-sup-0001-supporting information si-s01.pdf", "url": "https://authors.library.caltech.edu/records/7sk0g-48t54/files/2022gb007644-sup-0001-supporting information si-s01.pdf" }, { "basename": "2022gb007644-sup-0002-data set si-s01.xlsx", "url": "https://authors.library.caltech.edu/records/7sk0g-48t54/files/2022gb007644-sup-0002-data set si-s01.xlsx" } ], "pub_year": "2023", "author_list": "Kemeny, Preston Cosslett; Li, Gen K.; et al." }, { "id": "https://authors.library.caltech.edu/records/100t6-c8573", "eprint_status": "archive", "datestamp": "2025-01-06 20:08:27", "lastmod": "2025-02-12 00:15:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Most-E-R", "name": { "family": "Most", "given": "Elias" }, "orcid": "0000-0002-0491-1210" }, { "name": { "family": "Philippov", "given": "Alexander A." }, "orcid": "0000-0001-7801-0362" } ] }, "title": "Electromagnetic Precursors to Black Hole\u2013Neutron Star Gravitational Wave Events: Flares and Reconnection-powered Fast Radio Transients from the Late Inspiral", "ispublished": "pub", "full_text_status": "public", "keywords": "Astrophysical black holes; Neutron stars; Radio transient sources; Magnetospheric radio emissions; Plasma astrophysics; General relativity; Gravitational wave sources", "note": "

© 2023. The Author(s). Published by the American Astronomical Society.

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The authors are grateful for discussions with Benoit Cerutti, Sean McWilliams, and Navin Sridhar. E.R.M. acknowledges support by the National Science Foundation under grant No. AST-2307394. A.P. acknowledges support by the National Science Foundation under grant No. AST-1909458. This work was initiated during visits at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611, and at the Institute for Computational and Experimental Research in Mathematics in Providence, RI, which is supported by the National Science Foundation under grant No. DMS-1929284. This research was facilitated by the Multimessenger Plasma Physics Center (MPPC), NSF grant PHY-2206610. The simulations were performed on the NSF Frontera supercomputer under grant AST21006. E.R.M. acknowledges the use of Delta at the National Center for Supercomputing Applications (NCSA) through allocation PHY210074 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, which is supported by National Science Foundation grants #2138259, #2138286, #2138307, #2137603, and #2138296. Support also comes from the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.

\n\n

AMReX (Zhang et al. 2019), FUKA (Papenfort et al. 2021), Kadath (Grandclement 2010), matplotlib (Hunter 2007), numpy (Harris et al. 2020), and scipy (Virtanen et al. 2020).

", "abstract": "

The presence of magnetic fields in the late inspiral of black hole–neutron star binaries could lead to potentially detectable electromagnetic precursor transients. Using general-relativistic force-free electrodynamics simulations, we investigate premerger interactions of the common magnetosphere of black hole–neutron star systems. We demonstrate that these systems can feature copious electromagnetic flaring activity, which we find depends on the magnetic field orientation but not on black hole spin. Due to interactions with the surrounding magnetosphere, these flares could lead to fast-radio-burst-like transients and X-ray emission, with LEM\u22721041(B∗/1012G)2ergs−1 as an upper bound on the luminosity, where B* is the magnetic field strength on the surface of the neutron star.

", "date": "2023-10-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "956", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L33", "issn": "2041-8205", "official_url": "https://authors.library.caltech.edu/records/100t6-c8573", "funders": { "items": [ { "grant_number": "AST-2307394" }, { "grant_number": "AST-1909458" }, { "grant_number": "PHY-1607611" }, { "grant_number": "PHY-2206610" }, {} ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "TAPIR" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/2041-8213/acfdae", "primary_object": { "basename": "Most_2023_ApJL_956_L33.pdf", "url": "https://authors.library.caltech.edu/records/100t6-c8573/files/Most_2023_ApJL_956_L33.pdf" }, "pub_year": "2023", "author_list": "Most, Elias and Philippov, Alexander A." }, { "id": "https://authors.library.caltech.edu/records/bpqqc-k2g90", "eprint_status": "archive", "datestamp": "2023-10-26 18:52:41", "lastmod": "2023-10-26 18:52:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Biondi-Ettore", "name": { "family": "Biondi", "given": "Ettore" }, "orcid": "0000-0002-3305-0982" }, { "id": "Zhu-Weiqiang", "name": { "family": "Zhu", "given": "Weiqiang" }, "orcid": "0000-0003-2889-1493" }, { "id": "Li-Jiaxuan", "name": { "family": "Li", "given": "Jiaxuan" }, "orcid": "0000-0002-3766-0876" }, { "id": "Williams-Ethan-F", "name": { "family": "Williams", "given": "Ethan F." }, "orcid": "0000-0002-6471-4497" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" } ] }, "title": "An upper-crust lid over the Long Valley magma chamber", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

\u00a9 2023 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY).

\n\n

We would like to thank OptaSense for the support provided for this calibration experiment. In particular, we thank M. Karrenbach, V. Yartsev, and V. Bogdanov. We authors also thank the California Broadband Cooperative for providing access to the Digital 395 telecommunication fibers. We would like to thank J. R. Ryan-Davis, R. W. Clayton, and J. M. Jackson for suggestions on the initial manuscript draft. Last, we thank C. Iovine for the technical help provided in producing Fig. 5. The tomography workflow is part of a provisional U.S. patent filed by the California Institute of Technology (CIT file no. CIT-9029-P).

\n\n

This work was supported by the National Science Foundation (NSF) Faculty Early Career Development Program (CAREER), award number 1848166; Resnick Institute of Sustainability; and Gordon and Betty Moore Foundation.

\n\n

Conceptualization: E.B. and Z.Z. Methodology: E.B., W.Z., and J.L. Data collection and fieldwork: E.B. and E.F.W. Supervision: Z.Z. Writing\u2014original draft: E.B. Writing\u2014review and editing: E.B., Z.Z., W.Z., J.L., and E.W.

\n\n

All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Seismic data at conventional stations are from the Northern California Earthquake Data Center (https://ncedc.org/) and the Nevada Seismic Network (www.seismo.unr.edu/). The DAS travel times of the used events and velocity models are available at the Zenodo repository: https://doi.org/10.5281/zenodo.8270895.

\n\n

The authors declare that they have no competing interests.

", "abstract": "Geophysical characterization of calderas is fundamental in assessing their potential for future catastrophic volcanic eruptions. The mechanism behind the unrest of Long Valley Caldera in California remains highly debated, with recent periods of uplift and seismicity driven either by the release of aqueous fluids from the magma chamber or by the intrusion of magma into the upper crust. We use distributed acoustic sensing data recorded along a 100-kilometer fiber-optic cable traversing the caldera to image its subsurface structure. Our images highlight a definite separation between the shallow hydrothermal system and the large magma chamber located at ~12-kilometer depth. The combination of the geological evidence with our results shows how fluids exsolved through second boiling provide the source of the observed uplift and seismicity.", "date": "2023-10-20", "date_type": "published", "publication": "Science Advances", "volume": "9", "number": "42", "publisher": "American Association for the Advancement of Science", "pagerange": "eadi9878", "issn": "2375-2548", "official_url": "https://authors.library.caltech.edu/records/bpqqc-k2g90", "funders": { "items": [ { "grant_number": "EAR-1848166" }, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Seismological-Laboratory" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.adi9878", "pmcid": "PMC10584340", "primary_object": { "basename": "sciadv.adi9878.pdf", "url": "https://authors.library.caltech.edu/records/bpqqc-k2g90/files/sciadv.adi9878.pdf" }, "related_objects": [ { "basename": "sciadv.adi9878_sm.pdf", "url": "https://authors.library.caltech.edu/records/bpqqc-k2g90/files/sciadv.adi9878_sm.pdf" } ], "pub_year": "2023", "author_list": "Biondi, Ettore; Zhu, Weiqiang; et al." }, { "id": "https://authors.library.caltech.edu/records/0er9e-5vx35", "eprint_status": "archive", "datestamp": "2023-10-30 19:31:12", "lastmod": "2025-11-22 02:33:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zott-Michael-D", "name": { "family": "Zott", "given": "Michael D." }, "orcid": "0000-0003-0535-0512" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Improving Molecular Iron Ammonia Oxidation Electrocatalysts via Substituent Effects that Modulate Standard Potential and Stability", "ispublished": "pub", "full_text_status": "public", "keywords": "Catalysis; General Chemistry", "note": "

\u00a9 2023 American Chemical Society.

\n\n

The authors are grateful to the National Institutes of Health (NIH GM070757) for support of this research. M.D.Z. acknowledges the Resnick Sustainability Institute at Caltech and the National Science Foundation (DGE-1745301) for support via Graduate Fellowships.

\n\n

The authors declare no competing financial interest.
 

 

", "abstract": "

Molecular ammonia oxidation (AO) catalysis is a rapidly evolving research area. Among the catalysts studied, featuring metals including ruthenium, iron, manganese, nickel, and copper, polypyridyl iron complexes are attractive owing to their fast catalytic rates and significant turnover numbers (TON). Building upon our previous work on AO using the polypyridyl systems [(TPA)Fe(MeCN)\u2082]\u00b2\u207a and [(BPM)Fe(MeCN)\u2082]\u00b2\u207a, this study investigates factors that impact rate and TON within and across catalyst series based on these polypyridyl ligand frameworks. The synthesis and analysis of derivatives functionalized in the 4-pyridyl position with electron-donating and electron-withdrawing groups (NMe\u2082, OMe, CF\u2083) are described; a combination of electroanalytical, UV\u2013vis, and NMR analyses provide insights into the relative importance of catalyst standard potential (E\u00b0) and 4-pyridyl substituent to rate and stability. These findings constrain hypotheses rationalizing the nature of improved catalysis by comparing two classes of polypyridyl ligands for [(L\u2090\u1d64\u2093)Fe(MeCN)\u2082]\u00b2\u207a species and help define a roadmap for future catalyst development. For the most active catalyst studied herein, [(BPM^(OMe))Fe(MeCN)\u2082]\u00b2\u207a, a TON of 381 is demonstrated after 48 h of sustained catalysis.

", "date": "2023-10-18", "date_type": "published", "publication": "ACS Catalysis", "volume": "13", "publisher": "American Chemical Society", "pagerange": "14052-14057", "issn": "2155-5435", "official_url": "https://authors.library.caltech.edu/records/0er9e-5vx35", "funders": { "items": [ { "grant_number": "GM070757" }, {}, { "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscatal.3c03772", "primary_object": { "basename": "cs3c03772_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0er9e-5vx35/files/cs3c03772_si_001.pdf" }, "pub_year": "2023", "author_list": "Zott, Michael D. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/nyv87-gj396", "eprint_id": 121756, "eprint_status": "archive", "datestamp": "2023-08-22 21:31:40", "lastmod": "2025-11-21 21:14:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shin-Cheol-Hwan", "name": { "family": "Shin", "given": "Cheol-Hwan" }, "orcid": "0000-0002-1209-736X" }, { "id": "Yu-Ted-H", "name": { "family": "Yu", "given": "Ted H." }, "orcid": "0000-0003-3202-0981" }, { "id": "Lee-Ha-Young", "name": { "family": "Lee", "given": "Ha-Young" }, "orcid": "0000-0001-6177-6097" }, { "id": "Lee-Byeong-June", "name": { "family": "Lee", "given": "Byeong-June" } }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Yu-Jong-Sung", "name": { "family": "Yu", "given": "Jong-Sung" }, "orcid": "0000-0002-8805-012X" } ] }, "title": "Ru-loaded pyrrolic-N-doped extensively graphitized porous carbon for high performance electrochemical hydrogen evolution", "ispublished": "pub", "full_text_status": "public", "keywords": "Process Chemistry and Technology; General Environmental Science; Catalysis", "note": "\u00a9 2023 Elsevier. \n\nThis work was generously supported by the National Research Foundation (2019R1A2C2086770 and 2023K2A9A2A23000259) funded by the Korea Ministry of Science, ICT & Future Planning. Authors would also like to thank the Korean Basic Science Institute (KBSI) at Jeonju and Daejeon for electron microscope analysis. T.H.Y., S.K., and W.A.G. thank ONR (N00014\u201319-1\u20132081) for support. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute. \n\nCRediT authorship contribution statement. Cheol-Hwan Shin: Conceptualization, Methodology, Investigation, Formal analysis, Visualization, Writing \u2013 original draft, Writing \u2013 review & editing. Ted H. Yu: Formal analysis, Methodology, Visualization, Writing \u2013 original draft. Ha-Young Lee: Formal analysis, Data curation. Byeong-June Lee: Formal analysis, Data curation. Soonho Kwon: Formal analysis, Data curation. William A. Goddard III: Project administration, Funding acquisition, Conceptualization, Supervision, Writing \u2013 review & editing. Jong-Sung Yu: Project administration, Funding acquisition, Conceptualization, Supervision, Writing \u2013 review & editing. \n\nData Availability. Data will be made available on request. Computational data were uploaded to github: https://github.com/tedhyu/Ru_HER. \n\nThe authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Jong-Sung Yu reports financial support was provided by National Research Foundation of Korea. Jong-Sung Yu reports a relationship with National Research Foundation of Korea that includes: funding grants. The authors declare that they have no other known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.", "abstract": "Herein, we report a novel methodology for preparation of new N-doped extensively graphitized porous carbon (N-GPC) as a new catalyst support for Ru nanoparticles (NPs) with dramatically improved hydrogen evolution reaction (HER) activity. Our method is remarkably simple: pyrolyzing g-C3N4 in the presence of Mg metal. Here, we show that Mg plays marvelous dual roles as a reducing agent to graphitize the g-C3N4 precursor at low temperature and as a precursor for Mg3N2, which generates network-structured porous carbon as a new porogen. This offers highly robust graphitized carbon with high electrical conductivity, network-structured high porosity, and proper N content, most desired as a catalyst support. As-prepared Ru/N-GPC catalyst shows a remarkably low overpotential of 9.6 mV (vs. RHE) at 10 mA/cm2, which is near ideal, providing 12 times faster hydrogen production rate than state-of-the-art Pt/C. We explain the atomistic basis for this low overpotential and superb stability via Grand canonical quantum mechanics calculations. These calculations show that pyrrolic-N in the support strengthens the coupling to the Ru NP while weakening the binding of H to Ru NP to accelerate the Tafel step.", "date": "2023-10-05", "date_type": "published", "publication": "Applied Catalysis B", "volume": "334", "publisher": "Elsevier", "pagerange": "Art. No. 122829", "id_number": "CaltechAUTHORS:20230607-309304000.1", "issn": "0926-3373", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230607-309304000.1", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Foundation of Korea", "grant_number": "2019R1A2C2086770" }, { "agency": "National Research Foundation of Korea", "grant_number": "2023K2A9A2A23000259" }, { "agency": "Ministry of Science, ICT and Future Planning (Korea)" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014\u201319-1\u20132081" }, { "agency": "Resnick Sustainability Institute" } ] }, "other_numbering_system": { "items": [ { "id": "1573", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apcatb.2023.122829", "pub_year": "2023", "author_list": "Shin, Cheol-Hwan; Yu, Ted H.; et al." }, { "id": "https://authors.library.caltech.edu/records/fj632-dsb85", "eprint_status": "archive", "datestamp": "2023-10-06 16:28:50", "lastmod": "2025-11-22 03:58:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Afik-Eldad", "name": { "family": "Afik", "given": "Eldad" }, "orcid": "0000-0002-8887-2166" }, { "id": "Liu-Toni-J-B", "name": { "family": "Liu", "given": "Toni J. B." }, "orcid": "0009-0001-3142-5402" }, { "id": "Meyerowitz-E-M", "name": { "family": "Meyerowitz", "given": "Elliot M." }, "orcid": "0000-0003-4798-5153" } ] }, "title": "Macroscopic waves, biological clocks and morphogenesis driven by light in a giant unicellular green alga", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary", "note": "

\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

\n\n

The authors thank A. Kornfeld for the computer-aided design of the 3d-printed apparatus, as well as Caltech Library Techlab and staff for 3D Printers access, materials and support. We are grateful to L.J. Schulman, M. Mussel and T. Li for stimulating discussions through various stages of the research, as well as to L. Michaeli, A.I. Flamholz, G. Manella and S.A. Wilson for helpful discussions and critical comments on the manuscript. E.A. is thankful for fruitful discussions at the SRBR2022 and EBRS2022 meetings. Distributed image processing was conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. The laboratory of E.M.M. is supported by the Howard Hughes Medical Institute. E.A. has been awarded the Zuckerman Israeli Postdoctoral Scholar, Zuckerman STEM Leadership Program, and the Biology and Biological Engineering Divisional Fellowship, Caltech. T.J.B.L. has been awarded the Summer Undergraduate Research Fellowship (SURF), Caltech. This article is subject to HHMI's Open Access to Publications policy. HHMI lab heads have previously granted a nonexclusive CC BY 4.0 license to the public and a sublicensable license to HHMI in their research articles. Pursuant to those licenses, the author-accepted manuscript of this article can be made freely available under a CC BY 4.0 license immediately upon publication.

\n\n

Conceptualisation: E.M.M proposed studying morphogenesis in Caulerpa; E.A. designed the study; Methodology: E.A. designed the experimental system and analysis; Investigation: E.A. performed the measurements; E.A. and T.J.B.L. performed computational analysis; Visualisation: E.A. and T.J.B.L.; Funding acquisition: E.M.M.; Writing\u2014original draft: E.A.; Writing\u2014review & editing: E.A. and E.M.M.; All authors discussed and commented on the manuscript.

\n\n

The datasets generated and analysed during the current study are available in the figshare repository, https://doi.org/10.6084/m9.figshare.23797020.

\n\n

All programming and computer aided analysis has been done using open-source projects, primarily tools from the Scientific Python ecosystem28: SciPy29, pandas30, IPython and JupyterLab31; image processing has been distributed using dask and xarray; visualisation has been done using HoloViz and Matplotlib. Custom computer codes used to analyse the results reported in the manuscript are available in the figshare repository, 10.6084/m9.figshare.23797020, and from the corresponding authors on reasonable request.

\n\n

The authors declare no competing interests.

", "abstract": "

A hallmark of self-organisation in living systems is their capacity to stabilise their own dynamics, often appearing to anticipate and act upon potential outcomes. Caulerpa brachypus is a marine green alga consisting of differentiated organs resembling leaves, stems and roots. While an individual can exceed a metre in size, it is a single multinucleated giant cell. Thus Caulerpa presents the mystery of morphogenesis on macroscopic scales in the absence of cellularization. The experiments reported here reveal self-organised waves of greenness \u2014 chloroplasts \u2014 that propagate throughout the alga in anticipation of the day-night light cycle. Using dynamical systems analysis we show that these waves are coupled to a self-sustained oscillator, and demonstrate their entrainment to light. Under constant conditions light intensity affects the natural period and drives transition to temporal disorder. Moreover, we find distinct morphologies depending on light temporal patterns, suggesting waves of chlorophyll could link biological oscillators to metabolism and morphogenesis in this giant single-celled organism.

", "date": "2023-10-04", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "6204", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/fj632-dsb85", "funders": { "items": [ {}, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1038/s41467-023-41813-6", "pmcid": "PMC10550971", "primary_object": { "basename": "s41467-023-41813-6.pdf", "url": "https://authors.library.caltech.edu/records/fj632-dsb85/files/s41467-023-41813-6.pdf" }, "related_objects": [ { "basename": "41467_2023_41813_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/fj632-dsb85/files/41467_2023_41813_MOESM1_ESM.pdf" }, { "basename": "41467_2023_41813_MOESM3_ESM.pdf", "url": "https://authors.library.caltech.edu/records/fj632-dsb85/files/41467_2023_41813_MOESM3_ESM.pdf" }, { "basename": "41467_2023_41813_MOESM4_ESM.mp4", "url": "https://authors.library.caltech.edu/records/fj632-dsb85/files/41467_2023_41813_MOESM4_ESM.mp4" } ], "pub_year": "2023", "author_list": "Afik, Eldad; Liu, Toni J. B.; et al." }, { "id": "https://authors.library.caltech.edu/records/9xae2-2b037", "eprint_status": "archive", "datestamp": "2023-12-12 17:43:50", "lastmod": "2025-11-22 00:06:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" } ] }, "title": "Inclination of polarized illumination increases symmetry of structures grown via inorganic phototropism", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; Process Chemistry and Technology; Mechanics of Materials; General Materials Science", "note": "

\u00a9 The Royal Society of Chemistry 2023.

\n\n

This work was supported by the National Science Foundation, Directorate for Mathematical & Physical Sciences, Division of Materials Research under Award Number DMR 1905963. Research was in part carried out at the Molecular Materials Resource Center in the Beckman Institute of the California Institute of Technology. The authors gratefully acknowledge J. Thompson for insightful discussions, W.-H. Cheng and S. Yalamanchili for assistance with substrate preparation, and R. Gerhart, N. Hart, and B. Markowicz for assistance with photoelectrochemical cell fabrication. MCM acknowledges a Graduate Research Fellowship from the National Science Foundation and the Resnick Institute at Caltech for fellowship support.

\n\n

The authors declare no conflict of interest.

\n\n

This article is part of the themed collection: Celebrating 10 Years of Materials Horizons: 10th Anniversary Collection

", "abstract": "

Inclination of unpatterned, linearly polarized illumination in the plane of the electric field oscillation effected increased directional feature alignment and decreased off-axis order in Se\u2013Te deposits generated by inorganic phototropic growth relative to that produced using normal incidence. Optically based growth simulations reproduced the experimental results indicating a photonic basis for the morphology change. Modeling of the light scattering at the growth interface revealed that illumination inclination enhances scattering that localizes the optical field along the polarization plane and suppresses cooperativity in defect-driven scattering. Thus, the symmetry of the deposited structures increased as the asymmetry of the illumination increased, as measured by the inclination of the illumination incidence away from the surface normal.

", "date": "2023-10", "date_type": "published", "publication": "Materials Horizons", "volume": "10", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "4251-4255", "issn": "2051-6347", "official_url": "https://authors.library.caltech.edu/records/9xae2-2b037", "funders": { "items": [ { "grant_number": "DMR-1905963" }, { "grant_number": "NSF Graduate Research Fellowship" }, { "grant_number": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d3mh00839h", "primary_object": { "basename": "d3mh00839h1.pdf", "url": "https://authors.library.caltech.edu/records/9xae2-2b037/files/d3mh00839h1.pdf" }, "pub_year": "2023", "author_list": "Meier, Madeline C.; Lewis, Nathan S.; et al." }, { "id": "https://authors.library.caltech.edu/records/qd23d-g4r92", "eprint_status": "archive", "datestamp": "2023-09-21 16:04:11", "lastmod": "2025-11-21 21:51:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yao-Yuxing", "name": { "family": "Yao", "given": "Yuxing" }, "orcid": "0000-0003-0337-6372" }, { "id": "McFadden-Molly-E", "name": { "family": "McFadden", "given": "Molly E." }, "orcid": "0000-0003-3174-6385" }, { "id": "Luo-Stella-M", "name": { "family": "Luo", "given": "Stella M." }, "orcid": "0000-0003-4003-7468" }, { "id": "Barber-Ross-W", "name": { "family": "Barber", "given": "Ross W." } }, { "id": "Kang-Elin", "name": { "family": "Kang", "given": "Elin" } }, { "id": "Bar-Zion-Avinoam", "name": { "family": "Bar-Zion", "given": "Avinoam" }, "orcid": "0000-0002-7564-9467" }, { "id": "Smith-Cameron-A-B", "name": { "family": "Smith", "given": "Cameron A. B." } }, { "id": "Jin-Zhiyang", "name": { "family": "Jin", "given": "Zhiyang" }, "orcid": "0000-0002-4411-6991" }, { "id": "Legendre-Mark", "name": { "family": "Legendre", "given": "Mark" }, "orcid": "0009-0008-5910-1574" }, { "id": "Ling-Bill", "name": { "family": "Ling", "given": "Bill" }, "orcid": "0000-0002-1276-7204" }, { "id": "Malounda-Dina", "name": { "family": "Malounda", "given": "Dina" }, "orcid": "0000-0001-7086-9877" }, { "id": "Torres-Andrea", "name": { "family": "Torres", "given": "Andrea" } }, { "id": "Hamza-Tiba", "name": { "family": "Hamza", "given": "Tiba" }, "orcid": "0000-0003-1555-9555" }, { "id": "Edwards-Chelsea-E-R", "name": { "family": "Edwards", "given": "Chelsea E. R." }, "orcid": "0000-0003-1540-7594" }, { "id": "Shapiro-M-G", "name": { "family": "Shapiro", "given": "Mikhail G." }, "orcid": "0000-0002-0291-4215" }, { "id": "Robb-M-J", "name": { "family": "Robb", "given": "Maxwell J." }, "orcid": "0000-0002-0528-9857" } ] }, "title": "Remote control of mechanochemical reactions under physiological conditions using biocompatible focused ultrasound", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "

\u00a9 2023 the Author(s). Published by PNAS. This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).

\n\n

We gratefully acknowledge financial support from the Division of Chemistry and Chemical Engineering (CCE) at Caltech through a CCE Innovation Grant (M.G.S. and M.J.R.), the Arnold and Mabel Beckman Foundation through a Beckman Young Investigator Award (M.J.R.), the David and Lucille Packard Foundation (M.G.S.), the Resnick Sustainability Institute (M.G.S.), the Institute for Collaborative Biotechnologies (W911NF-19-D-0001 to M.G.S.), and the National Institute of General Medical Sciences of the NIH (R35GM150988 to M.J.R.). M.E.M. was supported by an NSF Graduate Research Fellowship (DGE-1745301) and a Barbara J. Burger Fellowship from Caltech. A.B.-Z. was supported by the Lester Deutsch Fellowship and the Marie Sk\u0142odowska-Curie Postdoctoral Fellowship. C.A.B.S. was supported by the Human Frontiers Science Program Cross-Disciplinary Fellowship. We thank Dr. Scott Virgil for technical assistance and the Center for Catalysis and Chemical Synthesis of the Beckman Institute at Caltech for access to equipment. We gratefully acknowledge the Alfred P. Sloan Foundation for a Sloan Research Fellowship (M.J.R.) and the Camille and Henry Dreyfus Foundation for Camille Dreyfus Teacher-Scholar Awards (M.J.R. and M.G.S.). We thank the Kornfield group at Caltech for use of their GPC. M.J.R. thanks Prof. Peter Dervan for helpful discussions.

\n\n

Y.Y., M.E.M., M.G.S., and M.J.R. designed research; Y.Y., M.E.M., S.M.L., R.W.B., E.K., A.B.-Z., C.A.B.S., Z.J., M.L., B.L., D.M., A.T., T.H., and C.E.R.E. performed research; Y.Y., M.E.M., S.M.L., R.W.B., A.B.-Z., C.A.B.S., Z.J., M.G.S., and M.J.R. analyzed data; and Y.Y., M.E.M., M.G.S., and M.J.R. wrote the paper.

\n\n

All study data are included in the article and/or SI Appendix.

\n\n

M.G.S. is an Investigator of the Howard Hughes Medical Institute. Y.Y., M.E.M., M.G.S., and M.J.R. are inventors on a US provisional patent application submitted by California Institute of Technology (CIT 9023-P) covering the method disclosed herein. M.J.R. is an inventor on a US patent issued to California Institute of Technology (11,584,752) covering the chemistry for mechanically triggered release employed in this study.

", "abstract": "External control of chemical reactions in biological settings with spatial and temporal precision is a grand challenge for noninvasive diagnostic and therapeutic applications. While light is a conventional stimulus for remote chemical activation, its penetration is severely attenuated in tissues, which limits biological applicability. On the other hand, ultrasound is a biocompatible remote energy source that is highly penetrant and offers a wide range of functional tunability. Coupling ultrasound to the activation of specific chemical reactions under physiological conditions, however, remains a challenge. Here, we describe a synergistic platform that couples the selective mechanochemical activation of mechanophore-functionalized polymers with biocompatible focused ultrasound (FUS) by leveraging pressure-sensitive gas vesicles (GVs) as acousto-mechanical transducers. The power of this approach is illustrated through the mechanically triggered release of covalently bound fluorogenic and therapeutic cargo molecules from polymers containing a masked 2-furylcarbinol mechanophore. Molecular release occurs selectively in the presence of GVs upon exposure to FUS under physiological conditions. These results showcase the viability of this system for enabling remote control of specific mechanochemical reactions with spatiotemporal precision in biologically relevant settings and demonstrate the translational potential of polymer mechanochemistry.", "date": "2023-09-26", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "120", "number": "39", "publisher": "Proceedings of the National Academy of Sciences", "pagerange": "e2309822120", "issn": "0027-8424", "official_url": "https://authors.library.caltech.edu/records/qd23d-g4r92", "funders": { "items": [ { "grant_number": "CCE Innovation Grant" }, { "grant_number": "Beckman Young Investigator Award" }, { "grant_number": "Packard Fellowship" }, { "grant_number": "Explorer Grant" }, { "grant_number": "W911NF-19-D-0001" }, { "grant_number": "DGE-1745301" }, { "grant_number": "Sloan Research Fellowship" }, { "grant_number": "Camille Dreyfus Teacher-Scholar Award" }, { "grant_number": "R35GM150988" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Tianqiao-and-Chrissy-Chen-Institute-for-Neuroscience" } ] }, "doi": "10.1073/pnas.2309822120", "pmcid": "PMC10523651", "primary_object": { "basename": "yao-et-al-2023-remote-control-of-mechanochemical-reactions-under-physiological-conditions-using-biocompatible-focused.pdf", "url": "https://authors.library.caltech.edu/records/qd23d-g4r92/files/yao-et-al-2023-remote-control-of-mechanochemical-reactions-under-physiological-conditions-using-biocompatible-focused.pdf" }, "related_objects": [ { "basename": "pnas.2309822120.sapp.pdf", "url": "https://authors.library.caltech.edu/records/qd23d-g4r92/files/pnas.2309822120.sapp.pdf" } ], "pub_year": "2023", "author_list": "Yao, Yuxing; McFadden, Molly E.; et al." }, { "id": "https://authors.library.caltech.edu/records/79c0g-6br20", "eprint_status": "archive", "datestamp": "2023-12-12 17:31:10", "lastmod": "2023-12-12 17:31:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Reed-Jillian-T", "name": { "family": "Reed", "given": "Jillian T." }, "orcid": "0009-0005-2814-8415" }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Byrne-Sean-T", "name": { "family": "Byrne", "given": "Sean T." }, "orcid": "0000-0002-5466-3112" }, { "id": "Lin-Shaoyang", "name": { "family": "Lin", "given": "Shaoyang" }, "orcid": "0000-0003-4108-7299" }, { "id": "Ye-Alexandre-Z", "name": { "family": "Ye", "given": "Alexandre Z." }, "orcid": "0009-0003-4895-0160" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Spontaneous mesostructure formation produces optically transmissive Ni\u2013P films that are catalytically active for the photoelectrochemical hydrogen evolution reaction", "ispublished": "pub", "full_text_status": "public", "keywords": "Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment", "note": "

\u00a9 The Royal Society of Chemistry 2023.

\n\n

This work was supported by U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and under Award Number DE-SC0022087. XPS and UV-Vis data were collected at the Molecular Materials Resource Center of the Beckman Institute of the California Institute of Technology. M. C. M. acknowledges the Resnick Sustainability Institute at Caltech for fellowship support.

\n\n

NSL is a scientific founder of and consultant to a company, H2U Technologies, that is developing catalysts and electrolyzers for the production of hydrogen.

", "abstract": "

Ni\u2013P films that are catalytically active for the hydrogen-evolution reaction were electrodeposited onto photoactive Si substrates between 20 \u00b0C and 80 \u00b0C from an aqueous solution. Ni\u2013P films deposited at 20 \u00b0C and exposed to acidic environments spontaneously developed deep cracks. A substantial increase in optical transmission to the semiconducting substrate resulted without affecting the catalytic performance of the film. In contrast, Ni\u2013P films deposited at 80 \u00b0C only developed minor surface-level cracks and did not exhibit a substantial increase in optical transmission. During electrodeposition of the Ni\u2013P films at low temperatures, the uptake of parasitically evolved hydrogen generated partially defective Ni\u2013P, causing crack formation. Increases in the temperature of the electrodeposition bath increased the faradaic efficiency of Ni\u2013P deposition and consequently reduced the uptake of parasitically generated hydrogen. The defective Ni\u2013P films were converted to a crack-resistant material by thermally desorbing the excess hydrogen that was absorbed during the low-temperature electrodeposition process.

", "date": "2023-09-21", "date_type": "published", "publication": "Sustainable Energy & Fuels", "volume": "7", "number": "18", "publisher": "Royal Society of Chemistry", "pagerange": "4401-4406", "issn": "2398-4902", "official_url": "https://authors.library.caltech.edu/records/79c0g-6br20", "funders": { "items": [ { "grant_number": "DE-SC0004993" }, { "grant_number": "DE-SC0022087" }, { "grant_number": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d3se00378g", "primary_object": { "basename": "d3se00378g1.pdf", "url": "https://authors.library.caltech.edu/records/79c0g-6br20/files/d3se00378g1.pdf" }, "pub_year": "2023", "author_list": "Ifkovits, Zachary P.; Reed, Jillian T.; et al." }, { "id": "https://authors.library.caltech.edu/records/fkj0z-8d375", "eprint_status": "archive", "datestamp": "2023-09-07 15:45:07", "lastmod": "2025-11-22 01:42:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Rourke-Matthew-J", "name": { "family": "O'Rourke", "given": "Matthew J." }, "orcid": "0000-0002-5779-2577" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet K." }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Entanglement in the quantum phases of an unfrustrated Rydberg atom array", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary", "note": "

\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

\n\n

We thank M. Endres, J. Alicea, X. Chen, and H. Changlani for interesting discussions on Rydberg atom systems as well as entangled phases. M.J.O. acknowledges financial support from a US National Science Foundation Graduate Research Fellowship via grant DEG-1745301. G.K.C. acknowledges support from the US National Science Foundation via grant no. 2102505. G.K.C. is a Simons Investigator. Computations were conducted in the Resnick High Performance Computing Center, supported by the Resnick Sustainability Institute at the California Institute of Technology.

\n\n

M.J.O. and G.K.C. conceived the study. M.J.O. and G.K.C. contributed to the conceptual design of the new numerical methods. M.J.O. implemented the methods and carried out all numerical calculations. M.J.O. and G.K.C. analyzed the results and contributed to the writing of the manuscript.

\n\n

Data and plotting scripts for Figs. 3, 4, and 5 can be found at https://gitlab.com/mattorourke41/rydberg_public_data. All other data is available from the authors upon request.

\n\n

Source codes for the numerical simulations are available from the authors upon request.

\n\n

The authors declare no competing interests.

", "abstract": "

Recent experimental advances have stimulated interest in the use of large, two-dimensional arrays of Rydberg atoms as a platform for quantum information processing and to study exotic many-body quantum states. However, the native long-range interactions between the atoms complicate experimental analysis and precise theoretical understanding of these systems. Here we use new tensor network algorithms capable of including all long-range interactions to study the ground state phase diagram of Rydberg atoms in a geometrically unfrustrated square lattice array. We find a greatly altered phase diagram from earlier numerical and experimental studies, revealed by studying the phases on the bulk lattice and their analogs in experiment-sized finite arrays. We further describe a previously unknown region with a nematic phase stabilized by short-range entanglement and an order from disorder mechanism. Broadly our results yield a conceptual guide for future experiments, while our techniques provide a blueprint for converging numerical studies in other lattices.

", "date": "2023-09-05", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "5397", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/fkj0z-8d375", "funders": { "items": [ { "grant_number": "DGE-1745301" }, { "grant_number": "CHE-2102505" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-023-41166-0", "pmcid": "PMC10480489", "primary_object": { "basename": "41467_2023_41166_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/fkj0z-8d375/files/41467_2023_41166_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41467-023-41166-0.pdf", "url": "https://authors.library.caltech.edu/records/fkj0z-8d375/files/s41467-023-41166-0.pdf" } ], "pub_year": "2023", "author_list": "O'Rourke, Matthew J. and Chan, Garnet K." }, { "id": "https://authors.library.caltech.edu/records/0pt9a-2h475", "eprint_status": "archive", "datestamp": "2024-05-03 16:00:27", "lastmod": "2024-05-03 16:00:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wu-Wenbo", "name": { "family": "Wu", "given": "Wenbo" }, "orcid": "0000-0002-6249-8065" }, { "id": "Shen-Zhichao", "name": { "family": "Shen", "given": "Zhichao" }, "orcid": "0000-0003-0458-5264" }, { "id": "Peng-Shirui", "name": { "family": "Peng", "given": "Shirui" }, "orcid": "0000-0002-4616-4604" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" }, { "id": "Callies-J", "name": { "family": "Callies", "given": "J\u00f6rn" }, "orcid": "0000-0002-6815-1230" } ] }, "title": "Seismic Ocean Thermometry Using CTBTO Hydrophones", "ispublished": "pub", "full_text_status": "public", "note": "

© 2023. American Geophysical Union.

\n\n
\n

This material is based upon work supported by the Resnick Sustainability Institute and by the National Science Foundation under Grants OCE-2023161 and OCE-2241663. We thank two anonymous reviewers, whose comments have helped improve this manuscript.

\n
\n\n
\n
\n\n\n

The IMS hydrophone data are available directly from the CTBTO upon request and signing a confidentiality agreement to access the virtual Data Exploitation Centre (vDEC; https://www.ctbto.org/resources/for-researchers-experts/vdec). All seismic data were downloaded through IRIS Data Management Center https://ds.iris.edu/ds/nodes/dmc/, including the seismic networks II (GSN; https://doi.org/10.7914/SN/II), MY, PS, GE (https://doi.org/10.14470/TR560404). Global Seismographic Network (GSN) is a cooperative scientific facility operated jointly by the Incorporated Research Institutions for Seismology (IRIS), the United States Geological Survey (USGS) and the National Science Foundation (NSF), under Cooperative Agreement EAR-1261681. Bathymetry data were downloaded from and freely available at https://download.gebco.net/. The sediment thickness data were downloaded from https://ngdc.noaa.gov/mgg/sedthick/ (Straume et al., 2019). The Argo data were downloaded from https://sio-argo.ucsd.edu/RG_Climatology.html (Argo, 2000). Argo data were collected and made freely available by the International Argo Program and the national programs that contribute to it (http://www.argo.ucsd.edu, http://argo.jcommops.org). The Argo Program is part of the Global Ocean Observing System. The ECCO data were available at https://podaac.jpl.nasa.gov/dataset/ECCO_L4_TEMP_SALINITY_05DEG_DAILY_V4R4 (Fenty & Wang, 2020). The processing code is available at https://github.com/joernc/SOT (joernc et al., 2023).

\n

Supporting information S1

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Table S1

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\n
\n\n

The views expressed in the paper are those of the authors and do not necessarily represent those of the CTBTO.

", "abstract": "

Due to limited observational coverage, monitoring the warming of the global ocean, especially the deep ocean, remains a challenging sampling problem. Seismic ocean thermometry (SOT) complements existing point measurements by inferring large\u2010scale averaged ocean temperature changes using the sound waves generated by submarine earthquakes, called T waves. We demonstrate here that Comprehensive Nuclear\u2010Test\u2010Ban Treaty Organization (CTBTO) hydrophones can record T waves with a higher signal\u2010to\u2010noise ratio compared to a previously used land\u2010based T\u2010wave station. This allows us to use small earthquakes (magnitude <4.0), which occur much more frequently than large events, dramatically improving the resulting temporal resolution of SOT. We also find that the travel time changes of T waves at the land\u2010based T\u2010wave station and the CTBTO hydrophone show small but systematic differences, although the two stations are only about 20 km apart. We attribute this feature to their different acoustic mode components sampling different parts of the ocean. Applying SOT to two CTBTO hydrophones in the East Indian Ocean reveals signals from decadal warming, seasonal variations, and mesoscale eddies, some of which are missing or underestimated in previously available temperature reconstructions. This application demonstrates the great advantage of hydrophone stations for global SOT, especially in regions with a low seismicity level.

", "date": "2023-09", "date_type": "published", "publication": "Journal of Geophysical Research: Solid Earth", "volume": "128", "number": "9", "publisher": "AGU (pre-Wiley hosting)", "pagerange": "e2023JB026687", "issn": "2169-9313", "official_url": "https://authors.library.caltech.edu/records/0pt9a-2h475", "funders": { "items": [ {}, { "grant_number": "OCE\u20102023161" }, { "grant_number": "OCE\u20102241663" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Seismological-Laboratory" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2023jb026687", "primary_object": { "basename": "2023jb026687-sup-0002-table si-s01.txt", "url": "https://authors.library.caltech.edu/records/0pt9a-2h475/files/2023jb026687-sup-0002-table si-s01.txt" }, "related_objects": [ { "basename": "JGR Solid Earth - 2023 - Wu - Seismic Ocean Thermometry Using CTBTO Hydrophones.pdf", "url": "https://authors.library.caltech.edu/records/0pt9a-2h475/files/JGR Solid Earth - 2023 - Wu - Seismic Ocean Thermometry Using CTBTO Hydrophones.pdf" }, { "basename": "2023jb026687-sup-0001-supporting information si-s01.pdf", "url": "https://authors.library.caltech.edu/records/0pt9a-2h475/files/2023jb026687-sup-0001-supporting information si-s01.pdf" } ], "pub_year": "2023", "author_list": "Wu, Wenbo; Shen, Zhichao; et al." }, { "id": "https://authors.library.caltech.edu/records/5v97q-b4c50", "eprint_status": "archive", "datestamp": "2023-10-02 21:57:09", "lastmod": "2023-10-02 21:57:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Tong-Z-Jaron", "name": { "family": "Tong", "given": "Z. Jaron" }, "orcid": "0000-0001-9329-8034" }, { "id": "Bim-Daniel", "name": { "family": "B\u00edm", "given": "Daniel" }, "orcid": "0000-0003-3100-4293" }, { "id": "Turro-Raymond-F", "name": { "family": "Turro", "given": "Raymond F." }, "orcid": "0000-0001-9774-4556" }, { "id": "Kazmierczak-Nathanael-P", "name": { "family": "Kazmierczak", "given": "Nathanael P." }, "orcid": "0000-0002-7822-6769" }, { "id": "Chalupsk\u00fd-Jakub", "name": { "family": "Chalupsk\u00fd", "given": "Jakub" }, "orcid": "0000-0002-1584-9272" }, { "id": "Reisman-S-E", "name": { "family": "Reisman", "given": "Sarah E." }, "orcid": "0000-0001-8244-9300" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Electronic Structures of Nickel(II)-Bis(indanyloxazoline)-dihalide Catalysts: Understanding Ligand Field Contributions That Promote C(sp\u00b2)\u2013C(sp\u00b3) Cross-Coupling", "ispublished": "pub", "full_text_status": "public", "keywords": "Inorganic Chemistry; Physical and Theoretical Chemistry", "note": "

\u00a9 2023 American Chemical Society.

\n\n

We acknowledge the X-ray Crystallography Facility in the Beckman Institute at Caltech and the Dow Next Generation Instrumentation Grant for X-ray structure collection. Some computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. We are grateful for assistance from Alexander Q. Cusumano in collecting vibrational CD data and from Michael Zott in collecting VT UV\u2013vis\u2013NIR spectra. We thank Harry B. Gray and Jay R. Winkler for helpful discussions on equilibrium processes in spectroscopy and David E. Hill and David A. Cagan for helpful general discussions. N.P.K. acknowledges support from the Hertz Fellowship and from the National Science Foundation Graduate Research Fellowship under grant no. DGE-1745301. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 883987 (D.B.). Support has been provided by the Grant Agency of the Czech Republic (20-06451Y to J.C.). Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R35-GM142595) (R.G.H.). S.E.R. acknowledges financial support from the NIH (R35GM118191).

\n\n

B.J.M. and Z.J.T. are co-first authors.

\n\n

The authors declare no competing financial interest.

", "abstract": "

NiII(IB) dihalide [IB = (3aR,3a\u2032R,8aS,8a\u2032S)-2,2\u2032-(cyclopropane-1,1-diyl)bis(3a,8a-dihydro-8H-indeno[1,2-d]-oxazole)] complexes are representative of a growing class of first-row transition-metal catalysts for the enantioselective reductive cross-coupling of C(sp\u00b2) and C(sp\u00b3) electrophiles. Recent mechanistic studies highlight the complexity of these ground-state cross-couplings but also illuminate new reactivity pathways stemming from one-electron redox and their significant sensitivities to reaction conditions. For the first time, a diverse array of spectroscopic methods coupled to electrochemistry have been applied to NiII-based precatalysts to evaluate specific ligand field effects governing key Ni-based redox potentials. We also experimentally demonstrate DMA solvent coordination to catalytically relevant Ni complexes. Coordination is shown to favorably influence key redox-based reaction steps and prevent other deleterious Ni-based equilibria. Combined with electronic structure calculations, we further provide a direct correlation between reaction intermediate frontier molecular orbital energies and cross-coupling yields. Considerations developed herein demonstrate the use of synergic spectroscopic and electrochemical methods to provide concepts for catalyst ligand design and rationalization of reaction condition optimization.

", "date": "2023-08-28", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "62", "number": "34", "publisher": "American Chemical Society", "pagerange": "14010-14027", "issn": "0020-1669", "official_url": "https://authors.library.caltech.edu/records/5v97q-b4c50", "funders": { "items": [ {}, { "agency": "H2020 Marie Sklodowska-Curie Actions", "grant_number": "883987" }, { "grant_number": "DGE-1745301" }, { "agency": "Grantov? Agentura Cesk? Republiky", "grant_number": "20-06451Y" }, { "grant_number": "R35-GM142595" }, { "grant_number": "R35-GM118191" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.3c02048", "pmcid": "PMC10530056", "primary_object": { "basename": "nihms-1923055.pdf", "url": "https://authors.library.caltech.edu/records/5v97q-b4c50/files/nihms-1923055.pdf" }, "related_objects": [ { "basename": "NIHMS1923055-supplement-Supporting_Information.pdf", "url": "https://authors.library.caltech.edu/records/5v97q-b4c50/files/NIHMS1923055-supplement-Supporting_Information.pdf" } ], "pub_year": "2023", "author_list": "McNicholas, Brendon J.; Tong, Z. Jaron; et al." }, { "id": "https://authors.library.caltech.edu/records/1jfez-8e034", "eprint_id": 122333, "eprint_status": "archive", "datestamp": "2023-08-22 20:54:19", "lastmod": "2025-04-25 00:32:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mukasa-Daniel", "name": { "family": "Mukasa", "given": "Daniel" }, "orcid": "0000-0001-8379-3648" }, { "id": "Wang-Minqiang", "name": { "family": "Wang", "given": "Minqiang" }, "orcid": "0000-0002-7775-8341" }, { "id": "Min-Jihong", "name": { "family": "Min", "given": "Jihong" }, "orcid": "0000-0002-5788-1473" }, { "id": "Yang-Yiran", "name": { "family": "Yang", "given": "Yiran" }, "orcid": "0000-0001-8770-8746" }, { "id": "Solomon-Samuel-A", "name": { "family": "Solomon", "given": "Samuel A." }, "orcid": "0000-0001-7199-6659" }, { "id": "Han-Hong", "name": { "family": "Han", "given": "Hong" }, "orcid": "0000-0002-2852-8662" }, { "id": "Ye-Cui", "name": { "family": "Ye", "given": "Cui" }, "orcid": "0000-0001-7689-6825" }, { "id": "Gao-Wei", "name": { "family": "Gao", "given": "Wei" }, "orcid": "0000-0002-8503-4562" } ] }, "title": "A Computationally Assisted Approach for Designing Wearable Biosensors toward Non\u2010Invasive Personalized Molecular Analysis", "ispublished": "pub", "full_text_status": "public", "keywords": "Mechanical Engineering; Mechanics of Materials; General Materials Science", "note": "\u00a9 2023 Wiley-VCH GmbH. \n\nD.M. and M.W. contributed equally to this work. This work was funded by the National Science Foundation grant 2145802, National Institutes of Health grants R01HL155815 and R21DK13266, Office of Naval Research grants N00014-21-1-2483 and N00014-21-1-2845, and Heritage Medical Research Institute. The authors gratefully acknowledge critical support and infrastructure provided for this work by the Kavli Nanoscience Institute at Caltech and thank Dr. Matthew Hunt for the help. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. The authors are also thankful for the support from Prof. William A. Goddard in the theoretical and computational implementation of QuantumDock, along with providing access to extra computing resources. \n\nThe authors declare no conflict of interest. \n\nData Availability Statement: The data that support the findings of this study are available in the Supporting Information of this article.\n\n

Supplemental Material - adma202212161-sup-0001-suppmat.pdf

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", "abstract": "Wearable sweat sensors have the potential to revolutionize precision medicine as they can non-invasively collect molecular information closely associated with an individual's health status. However, the majority of clinically relevant biomarkers cannot be continuously detected in situ using existing wearable approaches. Molecularly imprinted polymers (MIPs) are a promising candidate to address this challenge but haven't yet gained widespread use due to their complex design and optimization process yielding variable selectivity. Here, QuantumDock is introduced, an automated computational framework for universal MIP development toward wearable applications. QuantumDock utilizes density functional theory to probe molecular interactions between monomers and the target/interferent molecules to optimize selectivity, a fundamentally limiting factor for MIP development toward wearable sensing. A molecular docking approach is employed to explore a wide range of known and unknown monomers, and to identify the optimal monomer/cross-linker choice for subsequent MIP fabrication. Using an essential amino acid phenylalanine as the exemplar, experimental validation of QuantumDock is performed successfully using solution-synthesized MIP nanoparticles coupled with ultraviolet\u2013visible spectroscopy. Moreover, a QuantumDock-optimized graphene-based wearable device is designed that can perform autonomous sweat induction, sampling, and sensing. For the first time, wearable non-invasive phenylalanine monitoring is demonstrated in human subjects toward personalized healthcare applications.", "date": "2023-08-17", "date_type": "published", "publication": "Advanced Materials", "publisher": "Wiley", "pagerange": "Art. No. 2212161", "id_number": "CaltechAUTHORS:20230717-55915200.27", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230717-55915200.27", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ECCS-2145802" }, { "agency": "NIH", "grant_number": "R01HL155815" }, { "agency": "NIH", "grant_number": "R21DK13266" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-21-1-2483" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-21-1-2845" }, { "agency": "Heritage Medical Research Institute" } ] }, "local_group": { "items": [ { "id": "Heritage-Medical-Research-Institute" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/adma.202212161", "primary_object": { "basename": "adma202212161-sup-0003-videos1.mp4", "url": "https://authors.library.caltech.edu/records/1jfez-8e034/files/adma202212161-sup-0003-videos1.mp4" }, "related_objects": [ { "basename": "adma202212161-sup-0004-videos2.mp4", "url": "https://authors.library.caltech.edu/records/1jfez-8e034/files/adma202212161-sup-0004-videos2.mp4" }, { "basename": "adma202212161-sup-0005-videos3.mp4", "url": "https://authors.library.caltech.edu/records/1jfez-8e034/files/adma202212161-sup-0005-videos3.mp4" }, { "basename": "adma202212161-sup-0001-suppmat.pdf", "url": "https://authors.library.caltech.edu/records/1jfez-8e034/files/adma202212161-sup-0001-suppmat.pdf" }, { "basename": "adma202212161-sup-0002-datasets1.xlsx", "url": "https://authors.library.caltech.edu/records/1jfez-8e034/files/adma202212161-sup-0002-datasets1.xlsx" } ], "pub_year": "2023", "author_list": "Mukasa, Daniel; Wang, Minqiang; et al." }, { "id": "https://authors.library.caltech.edu/records/g677n-tbn19", "eprint_id": 122407, "eprint_status": "archive", "datestamp": "2023-08-22 21:17:35", "lastmod": "2025-11-22 02:18:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tong-Xiaoyu", "name": { "family": "Tong", "given": "Xiaoyu" }, "orcid": "0000-0002-1343-6335" }, { "id": "Yang-Ze\u2010Peng", "name": { "family": "Yang", "given": "Ze\u2010Peng" } }, { "id": "Del-Angel-Aguilar-Carlos-E", "name": { "family": "Del Angel Aguilar", "given": "Carlos E." } }, { "id": "Fu-G-C", "name": { "family": "Fu", "given": "Gregory C." }, "orcid": "0000-0002-0927-680X" } ] }, "title": "Iron\u2010Catalyzed Reductive Cross\u2010Coupling of Alkyl Electrophiles with Olefins", "ispublished": "pub", "full_text_status": "public", "keywords": "General Chemistry; Catalysis", "note": "\u00a9 2023 Wiley-VCH GmbH. \n\nWe thank Robert L. Anderson, Dr. Caiyou Chen, Hyungdo Cho, Dr. Dylan\u2005J. Freas, Dr. Asik Hossain, and Christian Johansen for assistance and helpful discussions. Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences; grant R35-GM145315), the Resnick Sustainability Institute, the John Stauffer Fund (support for C.\u2005E.\u2005D.\u2005A.), the Beckman Institute (support of the EPR facility and the Center for Catalysis and Chemical Synthesis), the Gordon and Betty Moore Foundation (support of the Center for Catalysis and Chemical Synthesis), the Dow Next-Generation Educator Fund (grant to the California Institute of Technology), and the Peters laboratory (M\u00f6ssbauer spectrometer). \n\nData Availability Statement: The data that support the findings of this study are available in the Supporting Information of this article. \n\nThe authors declare no conflict of interest.\n\n

Supplemental Material - anie202306663-sup-0001-misc_information.pdf

", "abstract": "In terms of its abundance and its minimal toxicity, iron has advantages relative to other transition metals. Although alkyl\u2013alkyl bond construction is central to organic synthesis, examples of iron-catalyzed alkyl\u2013alkyl couplings of alkyl electrophiles are relatively sparse. Herein we report an iron catalyst that achieves cross-coupling reactions of alkyl electrophiles wherein olefins, in the presence of a hydrosilane, are used in place of alkylmetal reagents. Carbon\u2013carbon bond formation proceeds at room temperature, and the method employs commercially available components (Fe(OAc)\u2082, Xantphos, and Mg(OEt)\u2082); interestingly, this set of reagents can be applied directly to a distinct hydrofunctionalization of olefins, hydroboration. Mechanistic studies are consistent with the generation of an alkyl radical from the alkyl electrophile, as well as with reversibility for elementary steps that precede carbon\u2013carbon bond formation (olefin binding to iron and \u03b2-migratory insertion).", "date": "2023-08-16", "date_type": "published", "publication": "Angewandte Chemie International Edition", "publisher": "Wiley", "pagerange": "Art. No. e202306663", "id_number": "CaltechAUTHORS:20230725-746869000.33", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-746869000.33", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R35-GM145315" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "John Stauffer Fund" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Dow Next Generation Education Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.202306663", "pmcid": "PMC10528270", "primary_object": { "basename": "anie202306663-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/g677n-tbn19/files/anie202306663-sup-0001-misc_information.pdf" }, "pub_year": "2023", "author_list": "Tong, Xiaoyu; Yang, Ze\u2010Peng; et al." }, { "id": "https://authors.library.caltech.edu/records/xhesv-wv708", "eprint_id": 122575, "eprint_status": "archive", "datestamp": "2023-08-22 21:29:33", "lastmod": "2025-11-22 01:39:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kerches-Braghiere-Renato", "name": { "family": "Braghiere", "given": "R. K." }, "orcid": "0000-0002-7722-717X" }, { "id": "Wang-Yujie", "name": { "family": "Wang", "given": "Y." }, "orcid": "0000-0002-3729-2743" }, { "id": "Gagn\u00e9\u2010Landmann-A", "name": { "family": "Gagn\u00e9\u2010Landmann", "given": "A." } }, { "id": "Brodrick-Philip-G", "name": { "family": "Brodrick", "given": "P. G." }, "orcid": "0000-0001-9497-7661" }, { "id": "Bloom-A-Anthony", "name": { "family": "Bloom", "given": "A. A." }, "orcid": "0000-0002-1486-1499" }, { "id": "Norton-Alexander-J", "name": { "family": "Norton", "given": "A. J." }, "orcid": "0000-0001-7708-3914" }, { "id": "Ma-Shuang", "name": { "family": "Ma", "given": "S." }, "orcid": "0000-0002-6494-724X" }, { "id": "Levvine-Paul", "name": { "family": "Levine", "given": "P." }, "orcid": "0000-0002-1248-6920" }, { "id": "Longo-Marcos", "name": { "family": "Longo", "given": "M." }, "orcid": "0000-0001-5062-6245" }, { "id": "Deck-Katherine-M", "name": { "family": "Deck", "given": "K." } }, { "id": "Gentine-Pierre", "name": { "family": "Gentine", "given": "P." }, "orcid": "0000-0002-0845-8345" }, { "id": "Worden-John-R", "name": { "family": "Worden", "given": "J. R." }, "orcid": "0000-0003-0257-9549" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "T." }, "orcid": "0000-0001-5687-2287" } ] }, "title": "The Importance of Hyperspectral Soil Albedo Information for Improving Earth System Model Projections", "ispublished": "pub", "full_text_status": "public", "keywords": "General Earth and Planetary Sciences", "note": "\u00a9 2023. The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. \n\nThis research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. California Institute of Technology. Government sponsorship acknowledged. Copyright 2023. All rights reserved. Part of this research was funded by Eric and Wendy Schmidt by recommendation of the Schmidt Futures program and by the Hopewell Fund. We acknowledge high-performance computing support from Cheyenne provided by NCAR's Computational and Information Systems Laboratory, sponsored by the National Science Foundation. A portion of this work was supported by the Earth Surface Mineral Dust Source Investigation (EMIT), a NASA Earth Ventures-Instrument (EVI-4) Mission. This work was supported in part by Resnick Sustainability Institute. \n\nData Availability Statement. The scripts to generate the global hyperspectral soil albedo map used in this study can be found in soil.jl (https://doi.org/10.5281/zenodo.7662527). Code and documentation of the in-development CliMA-Land model are publicly available at https://github.com/CliMA/Land and Zenodo (https://doi.org/10.5281/zenodo.7662527). Simulations using NCAR's Community Atmosphere Model (CAM-6.0, http://www.cesm.ucar.edu/models/cam), coupled with the Community Land Model (CLM 5.0, http://www.cgd.ucar.edu/tss/clm/) with prescribed surface ocean temperatures, a river transport model (MOSART, https://www.cesm.ucar.edu/models/cesm2/river) and the Los Alamos Sea Ice Model (CICE, https://www.cesm.ucar.edu/models/cice). The global reflectance maps and diagnostics plots of CAM and CLM are available in https://doi.org/10.5281/zenodo.7996096. \n\nThe authors declare no conflicts of interest relevant to this study.\n\n

Published - AGU_Advances_-_2023_-_Braghiere.pdf

Supplemental Material - 2023av000910-sup-0001-supporting_information_si-s01.docx

", "abstract": "AbstractEarth system models (ESMs) typically simplify the representation of land surface spectral albedo to two values, which correspond to the photosynthetically active radiation (PAR, 400\u2013700\u00a0nm) and the near infrared (NIR, 700\u20132,500\u00a0nm) spectral bands. However, the availability of hyperspectral observations now allows for a more direct retrieval of ecological parameters and reduction of uncertainty in surface reflectance. To investigate sensitivity and quantify biases of incorporating hyperspectral albedo information into ESMs, we examine how shortwave soil albedo affects surface radiative forcing and simulations of the carbon and water cycles. Results reveal that the use of two broadband values to represent soil albedo can introduce systematic radiative\u2010forcing differences compared to a hyperspectral representation. Specifically, we estimate soil albedo biases of \u00b10.2 over desert areas, which can result in spectrally integrated radiative forcing divergences of up to 30\u00a0W\u00a0m\u207b\u00b2, primarily due to discrepancies in the blue (404\u2013504\u00a0nm) and far\u2010red (702\u2013747\u00a0nm) regions. Furthermore, coupled land\u2010atmosphere simulations indicate a significant difference in net solar flux at the top of the atmosphere (>3.3\u00a0W\u00a0m\u207b\u00b2), which can impact global energy fluxes, rainfall, temperature, and photosynthesis. Finally, simulations show that considering the hyperspectrally resolved soil reflectance leads to increased maximum daily temperatures under current and future CO\u2082 concentrations.", "date": "2023-08", "date_type": "published", "publication": "AGU Advances", "volume": "4", "number": "4", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2023AV000910", "id_number": "CaltechAUTHORS:20230818-791138000.1", "issn": "2576-604X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230818-791138000.1", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Eric and Wendy Schmidt" }, { "agency": "Schmidt Futures Program" }, { "agency": "Hopewell Fund" }, { "agency": "NSF" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2023av000910", "primary_object": { "basename": "2023av000910-sup-0001-supporting_information_si-s01.docx", "url": "https://authors.library.caltech.edu/records/xhesv-wv708/files/2023av000910-sup-0001-supporting_information_si-s01.docx" }, "related_objects": [ { "basename": "AGU_Advances_-_2023_-_Braghiere.pdf", "url": "https://authors.library.caltech.edu/records/xhesv-wv708/files/AGU_Advances_-_2023_-_Braghiere.pdf" } ], "pub_year": "2023", "author_list": "Braghiere, R. K.; Wang, Y.; et al." }, { "id": "https://authors.library.caltech.edu/records/48bsx-nk147", "eprint_status": "archive", "datestamp": "2023-08-22 21:20:41", "lastmod": "2026-02-26 20:41:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Qiang", "name": { "family": "Sun", "given": "Qiang" }, "orcid": "0000-0002-4589-8040" }, { "id": "Oliveira-Nicholas-J", "name": { "family": "Oliveira", "given": "Nicholas J." } }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Tyukhtenko-Sergiy", "name": { "family": "Tyukhtenko", "given": "Sergiy" }, "orcid": "0000-0002-0446-9979" }, { "id": "Guo-Jason-J", "name": { "family": "Guo", "given": "Jason J." } }, { "id": "Myrthil-Nathalie", "name": { "family": "Myrthil", "given": "Nathalie" } }, { "id": "Lopez-Steven-A", "name": { "family": "Lopez", "given": "Steven A." }, "orcid": "0000-0002-8418-3638" }, { "id": "Kendrick-Ian", "name": { "family": "Kendrick", "given": "Ian" }, "orcid": "0000-0003-1664-0662" }, { "id": "Mukerjee-Sanjeev", "name": { "family": "Mukerjee", "given": "Sanjeev" }, "orcid": "0000-0002-2980-7655" }, { "id": "Ma-Lu", "name": { "family": "Ma", "given": "Lu" }, "orcid": "0000-0001-9646-0738" }, { "id": "Ehrlich-Steven-N", "name": { "family": "Ehrlich", "given": "Steven N." }, "orcid": "0000-0002-4570-8833" }, { "id": "Li-Jingkun", "name": { "family": "Li", "given": "Jingkun" }, "orcid": "0000-0003-1699-3089" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Yan-Yushan", "name": { "family": "Yan", "given": "Yushan" }, "orcid": "0000-0001-6616-4575" }, { "id": "Jia-Qingying", "name": { "family": "Jia", "given": "Qingying" }, "orcid": "0000-0002-4005-8894" } ] }, "title": "Understanding hydrogen electrocatalysis by probing the hydrogen-bond network of water at the electrified Pt\u2013solution interface", "ispublished": "pub", "full_text_status": "public", "keywords": "Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Electronic, Optical and Magnetic Materials", "note": "\u00a9 2023 Springer Nature Limited. \n\nThis work was supported by the Office of Naval Research (ONR) grant N000141712608 (Q.J.). This research used beamline 7-BM (QAS) of the National Synchrotron Light Source II, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory Contract DE-SC0012704. Beamline operations were supported in part by the Synchrotron Catalysis Consortium Grant DE-SC0012335. W.A.G. acknowledges support by the Liquid Sunlight Alliance, which is supported by the US DOE, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award number DE-SC0021266. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) for AIMD simulation, which is supported by the NSF grant number ACI-1548562. S.K. acknowledges support from the Resnick Sustainability Institute at Caltech. \n\nContributions: Q.J. conceived the project, designed the experiments and proposed the HER/HOR mechanism. Q.S. conducted the electrochemical experiments and the data analysis in S.M.'s lab partly under his supervision. S.T. and J.J.G. conducted the NMR experiments and analysed the data. Q.S. helped to prepare the NMR samples. S.K. and W.A.G. planned the AIMD calculations. N.M. and S.A.L. performed the DFT calculations and contributed to the writing of the DFT computational results. Y.Y. and N.J.O. conducted the in situ ATR-SEIRAS and data analysis. Y.Y. and N.J.O. repeated electrochemical RDE experiments. Q.S., L.M. and S.N.E. conducted the XAS experiments, and Q.J. did the data analysis. J.L. conducted the in situ surface-enhanced Raman and data analysis. Q.S. and I.K. conducted the AEMEL testing and analysed the data. Q.J. supervised the project and data analysis. Q.J., Y.Y., W.A.G., Q.S., N.J.O. and S.K. wrote the paper and prepared the figures. \n\nThe authors declare no competing interests.\n\n

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Supplemental Material - 41560_2023_1302_MOESM8_ESM.xlsx

Supplemental Material - 41560_2023_1302_MOESM9_ESM.mp4

", "abstract": "Rational construction of the electrode\u2013solution interface where electrochemical processes occur is of paramount importance in electrochemistry. Efforts to gain better control and understanding of the interface have been hindered by lack of probing methods. Here we show that the hydrogen evolution and oxidation reactions (HER/HOR) catalysed by platinum in base can be promoted by introduction of N-methylimidazoles at the platinum\u2013water interface. In situ spectroscopic characterization together with simulations indicate that the N-methylimidazoles facilitate diffusion of hydroxides across the interface by holding the second layer of water close to platinum surfaces, thereby promoting the HER/HOR. We thus propose that the HER/HOR kinetics of platinum in acid and base is governed by diffusion of protons and hydroxides, respectively, through the hydrogen-bond network of interfacial water by the Grotthuss mechanism. Moreover, we demonstrate a 40% performance improvement of an anion exchange membrane electrolyser by adding 1,2-dimethylimidazole into the alkali fed into its platinum cathode.", "date": "2023-08", "date_type": "published", "publication": "Nature Energy", "volume": "8", "publisher": "Nature Publishing Group", "pagerange": "859-869", "issn": "2058-7546", "official_url": "https://authors.library.caltech.edu/records/48bsx-nk147", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N000141712608" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012704" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012335" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41560-023-01302-y", "primary_object": { "basename": "41560_2023_1302_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41560_2023_1302_MOESM11_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM11_ESM.xlsx" }, { "basename": "41560_2023_1302_MOESM4_ESM.txt", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM4_ESM.txt" }, { "basename": "41560_2023_1302_MOESM6_ESM.txt", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM6_ESM.txt" }, { "basename": "41560_2023_1302_MOESM13_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM13_ESM.xlsx" }, { "basename": "41560_2023_1302_MOESM14_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM14_ESM.xlsx" }, { "basename": "41560_2023_1302_MOESM15_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM15_ESM.xlsx" }, { "basename": "41560_2023_1302_MOESM7_ESM.txt", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM7_ESM.txt" }, { "basename": "41560_2023_1302_MOESM8_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM8_ESM.xlsx" }, { "basename": "41560_2023_1302_MOESM10_ESM.mp4", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM10_ESM.mp4" }, { "basename": "41560_2023_1302_MOESM2_ESM.txt", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM2_ESM.txt" }, { "basename": "41560_2023_1302_MOESM5_ESM.txt", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM5_ESM.txt" }, { "basename": "41560_2023_1302_MOESM12_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM12_ESM.xlsx" }, { "basename": "41560_2023_1302_MOESM3_ESM.txt", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM3_ESM.txt" }, { "basename": "41560_2023_1302_MOESM9_ESM.mp4", "url": "https://authors.library.caltech.edu/records/48bsx-nk147/files/41560_2023_1302_MOESM9_ESM.mp4" } ], "pub_year": "2023", "author_list": "Sun, Qiang; Oliveira, Nicholas J.; et al." }, { "id": "https://authors.library.caltech.edu/records/bv9z3-hcv55", "eprint_status": "archive", "datestamp": "2024-05-03 17:37:18", "lastmod": "2025-11-22 03:37:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Miller-Kimberly-Litwin", "name": { "family": "Miller", "given": "Kimberly Litwin" }, "orcid": "0000-0002-4299-9006" }, { "id": "Schmeer-Maria-N", "name": { "family": "Schmeer", "given": "Maria N." }, "orcid": "0000-0002-5983-8719" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Ablation\u2010Limited Erosion Rates of Permafrost Riverbanks", "ispublished": "pub", "full_text_status": "public", "note": "

© 2023 American Geophysical Union.

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The authors would like to thank Kieran Dunne, Grace Knuth, Maryn Sanders, Emily Geyman, Niccolo Ragno, Anya Leeman, and Sara Polanco for help running the experiments and Chris Paola and Todd Ehlers for fruitful discussions. This work was supported by NSF Awards 2127442 and 2031532, Caltech's Resnick Sustainability Institute, and the National Defense Science and Engineering Graduate Fellowship.

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Original photographs, laser topography scans, sonar measurements, discharge measurements, bank weight fraction water, grain size measurements, temperature sensor data, and instrument calibrations have been uploaded to a FAIR data repository (Douglas, Miller, et al., 2023).

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Supporting information S1
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Movie S1
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", "abstract": "

Permafrost thaw is hypothesized to increase riverbank erosion rates, which threatens Arctic communities and infrastructure. However, existing erosion models have not been tested against controlled flume experiments with open\u2010channel flow past an erodible, hydraulically rough permafrost bank. We conducted temperature\u2010controlled flume experiments where turbulent water eroded laterally into riverbanks consisting of sand and pore ice. The experiments were designed to produce ablation\u2010limited erosion such that any thawed sediment was quickly transported away from the bank. Bank erosion rates increased linearly with water temperature, decreased with pore ice content, and were insensitive to changes in bank temperature, consistent with theory. However, erosion rates were approximately a factor of three greater than expected. The heightened erosion rates were due to a greater coefficient of heat transfer from the turbulent water to the permafrost bank caused by bank grain roughness. A revised ablation\u2010limited bank erosion model with a heat transfer coefficient that includes bank roughness matched our experimental results well. Results indicate that bank erosion along Arctic rivers can accelerate under scenarios of warming river water temperatures for cases where the cadence of bank erosion is set by pore\u2010ice melting rather than sediment entrainment.

", "date": "2023-08", "date_type": "published", "publication": "Journal of Geophysical Research: Earth Surface", "volume": "128", "number": "8", "publisher": "American Geophysical Union", "pagerange": "e2023JF007098", "issn": "2169-9003", "official_url": "https://authors.library.caltech.edu/records/bv9z3-hcv55", "funders": { "items": [ { "grant_number": "RISE-2127442" }, { "grant_number": "EAR-2031532" }, {}, {}, { "grant_number": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2023jf007098", "primary_object": { "basename": "JGR Earth Surface - 2023 - Douglas - Ablation\u2010Limited Erosion Rates of Permafrost Riverbanks.pdf", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/JGR Earth Surface - 2023 - Douglas - Ablation\u2010Limited Erosion Rates of Permafrost Riverbanks.pdf" }, "related_objects": [ { "basename": "2023jf007098-sup-0003-movie si-s02.mp4", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/2023jf007098-sup-0003-movie si-s02.mp4" }, { "basename": "2023jf007098-sup-0004-movie si-s03.mp4", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/2023jf007098-sup-0004-movie si-s03.mp4" }, { "basename": "2023jf007098-sup-0005-movie si-s04.mp4", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/2023jf007098-sup-0005-movie si-s04.mp4" }, { "basename": "2023jf007098-sup-0006-movie si-s05.mp4", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/2023jf007098-sup-0006-movie si-s05.mp4" }, { "basename": "2023jf007098-sup-0001-supporting information si-s01.docx", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/2023jf007098-sup-0001-supporting information si-s01.docx" }, { "basename": "2023jf007098-sup-0002-movie si-s01.mp4", "url": "https://authors.library.caltech.edu/records/bv9z3-hcv55/files/2023jf007098-sup-0002-movie si-s01.mp4" } ], "pub_year": "2023", "author_list": "Douglas, Madison M.; Miller, Kimberly Litwin; et al." }, { "id": "https://authors.library.caltech.edu/records/02gzj-9pd02", "eprint_status": "archive", "datestamp": "2023-10-13 22:13:45", "lastmod": "2025-11-22 04:05:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Caron-Huot-Simon", "name": { "family": "Caron-Huot", "given": "Simon" }, "orcid": "0000-0002-7005-9652" }, { "id": "Li-Yue-Zhou", "name": { "family": "Li", "given": "Yue-Zhou" }, "orcid": "0000-0002-3982-4838" }, { "id": "Parra-Martinez-Julio", "name": { "family": "Parra-Martinez", "given": "Julio" }, "orcid": "0000-0003-0178-1569" }, { "id": "Simmons-Duffin-D", "name": { "family": "Simmons-Duffin", "given": "David" }, "orcid": "0000-0002-2937-9515" } ] }, "title": "Graviton partial waves and causality in higher dimensions", "ispublished": "pub", "full_text_status": "public", "note": "

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. 

Funded by SCOAP3.

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We thank Cyuan-Han Chang, Clifford Cheung, Yanky Landau, Petr Kravchuk, and Sasha Zhiboedov for discussions. D.\u2009S.\u2009D., S.\u2009C.\u2009H., and Y.\u2009Z.\u2009L. are supported by the Simons Foundation through the Simons Collaboration on the Nonperturbative Bootstrap. DSD is also supported by a DOE Early Career Award under Grant No. DE-SC0019085. S.\u2009C.\u2009H. is also supported by the Canada Research Chair program, reference number CRC-2021-0042 and the Sloan Foundation. J.\u2009P.\u2009M. is supported by the DOE under Grant No. DE-SC0011632. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. This research was enabled in part by support provided by Calcul Qu\u00e9bec and Compute Canada (Narval and Graham clusters).

", "abstract": "

Do gravitational interactions respect the basic principles of relativity and quantum mechanics? We show that any graviton S-matrix that satisfies these assumptions cannot significantly differ from General Relativity at low energies. We provide sharp bounds on the size of potential corrections in terms of the mass M of new higher-spin states, in spacetime dimensions D \u2265 5 where the S-matrix does not suffer from infrared ambiguities. The key novel ingredient is the full set of SO(D \u2212 1) partial waves for this process, which we show how to efficiently compute with Young tableau manipulations. We record new bounds on the central charges of holographic conformal theories.

", "date": "2023-07-15", "date_type": "published", "publication": "Physical Review D", "volume": "108", "number": "2", "publisher": "American Physical Society", "pagerange": "026007", "issn": "2470-0010", "official_url": "https://authors.library.caltech.edu/records/02gzj-9pd02", "funders": { "items": [ {}, { "grant_number": "DE-SC0019085" }, { "grant_number": "CRC-2021-0042" }, {}, { "grant_number": "DE-SC0011632" }, {}, {} ] }, "local_group": { "items": [ { "id": "Walter-Burke-Institute-for-Theoretical-Physics" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevd.108.026007", "primary_object": { "basename": "GGGG4.txt", "url": "https://authors.library.caltech.edu/records/02gzj-9pd02/files/GGGG4.txt" }, "related_objects": [ { "basename": "GGGG5.txt", "url": "https://authors.library.caltech.edu/records/02gzj-9pd02/files/GGGG5.txt" }, { "basename": "GGGG6.txt", "url": "https://authors.library.caltech.edu/records/02gzj-9pd02/files/GGGG6.txt" }, { "basename": "GGGG7.txt", "url": "https://authors.library.caltech.edu/records/02gzj-9pd02/files/GGGG7.txt" }, { "basename": "GGGGd.txt", "url": "https://authors.library.caltech.edu/records/02gzj-9pd02/files/GGGGd.txt" }, { "basename": "PhysRevD.108.026007.pdf", "url": "https://authors.library.caltech.edu/records/02gzj-9pd02/files/PhysRevD.108.026007.pdf" } ], "pub_year": "2023", "author_list": "Caron-Huot, Simon; Li, Yue-Zhou; et al." }, { "id": "https://authors.library.caltech.edu/records/pc6yr-hqz29", "eprint_id": 122231, "eprint_status": "archive", "datestamp": "2023-08-22 21:22:35", "lastmod": "2024-01-19 17:34:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boyd-Emily-A", "name": { "family": "Boyd", "given": "Emily A." }, "orcid": "0000-0003-0150-5396" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Highly Selective Fe-Catalyzed Nitrogen Fixation to Hydrazine Enabled by Sm(II) Reagents with Tailored Redox Potential and pK\u2090", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "\u00a9 2023 American Chemical Society. \n\nThe authors thank the National Institutes of Health (R01 GM-075757) (for studies of Fe-mediated N\u2082RR); E.A.B. thanks the National Science Foundation for a Graduate Research Fellowship under Grant No. DGE-1745301. The authors also acknowledge the Resnick Sustainability Institute at Caltech for support of enabling facilities and the DOW Next Generation Fund for support of the EPR facility. \n\nAuthor Contributions: The manuscript was written through the contribution of all authors. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja3c03352_si_001.pdf

", "abstract": "
\n

Controlling product selectivity in multiproton, multielectron reductions of unsaturated small molecules is of fundamental interest in catalysis. For the N2 reduction reaction (N2RR) in particular, parameters that dictate selectivity for either the 6H+/6e– product ammonia (NH3) or the 4H+/4e– product hydrazine (N2H4) are poorly understood. To probe this issue, we have developed conditions to invert the selectivity of a tris(phosphino)borane iron catalyst (Fe), with which NH3 is typically the major product of N2R, to instead favor N2H4 as the sole observed fixed-N product (>99:1). This dramatic shift is achieved by replacing moderate reductants and strong acids with a very strongly reducing but weakly acidic SmII–(2-pyrrolidone) core supported by a hexadentate dianionic macrocyclic ligand (SmII–PH) as the net hydrogen-atom donor. The activity and efficiency of the catalyst with this reagent remain high (up to 69 equiv of N2H4 per Fe and 67% fixed-N yield per H+). However, by generating N2H4 as the kinetic product, the overpotential of this Sm-driven reaction is 700 mV lower than that of the mildest reported set of NH3-selective conditions with Fe. Mechanistic data support assignment of iron hydrazido(2−) species FeNNH2 as selectivity-determining: we infer that protonation of FeNNH2 at Nβ, favored by strong acids, releases NH3, whereas one-electron reduction to FeNNH2–, favored by strong reductants such as SmII–PH, produces N2H4 via reactivity initiated at Nα. Spectroscopic data also implicate a role for SmIII-binding to anionic FeN2– (via an Fe–N2- -SmIII species) with respect to catalytic efficacy.

\n
", "date": "2023-07-12", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "145", "number": "27", "publisher": "American Chemical Society", "pagerange": "14784-14792", "id_number": "CaltechAUTHORS:20230711-988247900.3", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230711-988247900.3", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01 GM-075757" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.3c03352", "primary_object": { "basename": "ja3c03352_si_001.pdf", "url": "https://authors.library.caltech.edu/records/pc6yr-hqz29/files/ja3c03352_si_001.pdf" }, "pub_year": "2023", "author_list": "Boyd, Emily A. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/v2a3f-f9350", "eprint_status": "archive", "datestamp": "2023-10-27 22:05:16", "lastmod": "2024-07-10 00:02:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Linghui", "name": { "family": "Wang", "given": "Linghui" }, "orcid": "0000-0003-2492-7364" }, { "id": "Kim-Tae-Hyun", "name": { "family": "Kim", "given": "Tae Hyun" }, "orcid": "0000-0003-3856-5325" }, { "id": "Costanza-Vincenzo", "name": { "family": "Costanza", "given": "Vincenzo" }, "orcid": "0000-0002-2409-0632" }, { "id": "Higdon-Nicholas-J", "name": { "family": "Higdon", "given": "Nicholas J." }, "orcid": "0000-0002-5806-1151" }, { "id": "Daraio-C", "name": { "family": "Daraio", "given": "Chiara" }, "orcid": "0000-0001-5296-4440" } ] }, "title": "Ion transport in thermally responsive pectin film", "ispublished": "pub", "full_text_status": "public", "keywords": "Physics and Astronomy (miscellaneous)", "note": "

\u00a9 2023 Author(s). Published under an exclusive license by AIP Publishing.
 

\n\n

This research was funded in part by the Samsung Electronic GRO Program and in part by the HMRI program at Caltech. We are grateful to the Molecular Materials Research Center (MMRC) in the Beckman Institute of the California Institute of Technology (Caltech) for access to their experimental facilities. We thank Dr. Bruce S. Brunschwig from MMRC and Dr. Yeong Suk Choi from Samsung for useful discussions. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.

\n\n

Linghui Wang: Conceptualization (lead); Data curation (lead); Formal analysis (lead); Investigation (lead); Methodology (lead); Software (lead); Validation (lead); Visualization (lead); Writing \u2013 original draft (lead); Writing \u2013 review & editing (lead). Tae Hyun Kim: Data curation (supporting); Methodology (supporting); Resources (supporting); Writing \u2013 review & editing (supporting). Vincenzo Costanza: Conceptualization (supporting); Resources (supporting); Validation (supporting); Writing \u2013 review & editing (supporting). Nicholas J. Higdon: Formal analysis (supporting); Validation (supporting); Writing \u2013 review & editing (supporting). Chiara Daraio: Conceptualization (equal); Formal analysis (equal); Funding acquisition (equal); Investigation (equal); Methodology (equal); Project administration (equal); Resources (equal); Supervision (equal); Validation (equal); Writing \u2013 review & editing (equal).

\n\n

Most of the data support the findings of this study are available within the paper. The data that support the findings of this study are available from the corresponding author upon reasonable request.

See the supplementary material for additional details on the sample fabrication, electrical measurements, infrared spectroscopy, and DFT calculation.

\n\n

The authors have no conflicts to disclose.

", "abstract": "

The ionic conductivity of CaCl\u2082-crosslinked pectin was found to exhibit a record-high temperature response, suggesting its potential applications in wearable devices and infrared sensors [R. Di Giacomo et al., Sci. Rob. 2, eaai9251 (2017)]. However, little was known about its ion conduction mechanisms and the origin of its high-temperature sensitivity. In this study, we perform controlled experiments and identify calcium ions as the dominant current carriers. By analyzing infrared spectra at different temperatures, we find that the temperature response is due to changes in ion mobility, rather than variations in ion number density. We compare measurements and modeling results of nine different multivalent ions and find a positive correlation between their temperature responses and their binding energy to pectin. While these findings are fundamental in nature, they provide relevant guidance for the future design of temperature-sensitive polymers and other materials for organic electronics.

", "date": "2023-07-10", "date_type": "published", "publication": "Applied Physics Letters", "volume": "123", "number": "2", "publisher": "American Institute of Physics", "pagerange": "021903", "issn": "0003-6951", "official_url": "https://authors.library.caltech.edu/records/v2a3f-f9350", "funders": { "items": [ { "grant_number": "SAMS.2016GRO" }, { "agency": "Heritage Medical Research Institute", "grant_number": "HMRI-15-09-01" } ] }, "local_group": { "items": [ { "id": "Heritage-Medical-Research-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/5.0142020", "primary_object": { "basename": "021903_1_5_0142020_suppl_material.zip", "url": "https://authors.library.caltech.edu/records/v2a3f-f9350/files/021903_1_5_0142020_suppl_material.zip" }, "related_objects": [ { "basename": "021903_1_5.0142020.pdf", "url": "https://authors.library.caltech.edu/records/v2a3f-f9350/files/021903_1_5.0142020.pdf" } ], "pub_year": "2023", "author_list": "Wang, Linghui; Kim, Tae Hyun; et al." }, { "id": "https://authors.library.caltech.edu/records/xdy8w-0tc45", "eprint_id": 122296, "eprint_status": "archive", "datestamp": "2023-08-22 21:21:13", "lastmod": "2023-10-20 20:25:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bruening-Meaghan-A", "name": { "family": "Bruening", "given": "Meaghan A." } }, { "id": "Xiong-Shuoyan", "name": { "family": "Xiong", "given": "Shuoyan" }, "orcid": "0000-0002-2579-4260" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "\u03b1,\u03c9-Diene Generation from Ethylene and Butadiene by Copolymer Upcycling", "ispublished": "pub", "full_text_status": "public", "keywords": "Renewable Energy, Sustainability and the Environment; General Chemical Engineering; Environmental Chemistry; General Chemistry", "note": "\u00a9 2023 American Chemical Society. \n\nWe are grateful to the Resnick Sustainability Institute at Caltech for financial support. We thank David VanderVelde for assistance with NMR spectroscopy. We thank the Dow Next Generation Educator Fund for support of NMR instrumentation. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - sc3c02569_si_001.pdf

", "abstract": "Linear \u03b1-olefins are accessed efficiently from ethylene in the Shell higher olefin process (SHOP), an industrial process practiced on a million-ton scale that generates a statistical mixture of C\u2084-C\u2083\u2080 products. An analogous general process for the preparation of a range of \u03b1,\u03c9-dienes is lacking. We herein report a two-step method that generates industrially relevant \u03b1,\u03c9-dienes. In the first step, ethylene and butadiene are copolymerized to generate copolymers with a variable butadiene content. A titanium bisphenoxide bisthiolate catalyst activated with methylaluminoxane (MAO) was selected for this step due to the high selectivity for 1,4-butadiene incorporation. Ethenolysis of the copolymers results in a distribution of \u03b1,\u03c9-dienes in the C\u2081\u2080-C\u2082\u2080 range. Depending on the conditions, linear trienes are also generated. The reported protocol provides a strategy for copolymer upcycling to value-added olefin products.", "date": "2023-07-10", "date_type": "published", "publication": "ACS Sustainable Chemistry & Engineering", "volume": "11", "number": "27", "publisher": "American Chemical Society", "pagerange": "9918-9923", "id_number": "CaltechAUTHORS:20230717-49907100.1", "issn": "2168-0485", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230717-49907100.1", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acssuschemeng.3c02569", "primary_object": { "basename": "sc3c02569_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xdy8w-0tc45/files/sc3c02569_si_001.pdf" }, "pub_year": "2023", "author_list": "Bruening, Meaghan A.; Xiong, Shuoyan; et al." }, { "id": "https://authors.library.caltech.edu/records/ys655-amx52", "eprint_id": 122046, "eprint_status": "archive", "datestamp": "2023-08-22 21:09:08", "lastmod": "2023-10-23 20:29:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "G\u00f6zde S." }, "orcid": "0000-0002-3007-1489" }, { "id": "Gibson-Donald-J", "name": { "family": "Gibson", "given": "Donald J." } }, { "id": "Yue-Xiaoyan", "name": { "family": "Yue", "given": "Xiaoyan" }, "orcid": "0000-0001-7920-1734" }, { "id": "Pan-Kelly", "name": { "family": "Pan", "given": "Kelly" } }, { "id": "Elishav-Eshel", "name": { "family": "Elishav", "given": "Eshel" } }, { "id": "Khandal-Hitaishi", "name": { "family": "Khandal", "given": "Hitaishi" }, "orcid": "0000-0002-3899-4325" }, { "id": "Horev-Guy", "name": { "family": "Horev", "given": "Guy" }, "orcid": "0000-0002-6632-9795" }, { "id": "Tarkowsk\u00e1-Danu\u0161e", "name": { "family": "Tarkowsk\u00e1", "given": "Danu\u0161e" }, "orcid": "0000-0003-1478-1904" }, { "id": "Cant\u00f3\u2010Pastor-Alex", "name": { "family": "Cant\u00f3\u2010Pastor", "given": "Alex" }, "orcid": "0000-0001-8571-1116" }, { "id": "Kong-Shuyao", "name": { "family": "Kong", "given": "Shuyao" }, "orcid": "0000-0002-3124-8899" }, { "id": "Manzano-Concepcion", "name": { "family": "Manzano", "given": "Concepcion" }, "orcid": "0000-0003-1592-5068" }, { "id": "Maloof-Julin-N", "name": { "family": "Maloof", "given": "Julin N." }, "orcid": "0000-0002-9623-2599" }, { "id": "Savaldi\u2010Goldstein-Sigal", "name": { "family": "Savaldi\u2010Goldstein", "given": "Sigal" }, "orcid": "0000-0003-3458-5783" }, { "id": "Brady-Siobhan-M", "name": { "family": "Brady", "given": "Siobhan M." }, "orcid": "0000-0001-9424-8055" } ] }, "title": "Phosphate deprivation\u2010induced changes in tomato are mediated by an interaction between brassinosteroid signaling and zinc", "ispublished": "pub", "full_text_status": "public", "keywords": "Plant Science; Physiology", "note": "\u00a9 2023 The Authors. New Phytologist \u00a9 2023 New Phytologist Foundation. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. \n\nWe thank Tsuyoshi Nakagawa for the pGWB402 plasmid. We thank Dr A. Singh (NIPGR) for helpful discussions. GSD was supported by the Resnick Sustainability Institute Postdoctoral Fellowship. This work was funded by a BARD Research Grant Agreement No. IS-4827-15 to SMB and SS-G. Additional support was provided by an HHMI Faculty Scholar and National Science Foundation 1856749, 2119820 and 1238243 and SS-G has received funding from the European Union's Horizon 2020 research and innovation program under the Grant Agreement No. (727929) (TOMRES). DT is grateful for financial support from European Regional Development Fund Project, Centre for Experimental Plant Biology No. CZ.02.1.01/0.0/0.0/16_019/0000738. \n\nAuthor contributions\nGSD, DJG and SMB designed the research. GSD performed all experiments and analysis of the Slbzr1 mutant. DJG performed all experiments and analysis relating to the S. pennellii results. XY, KP and SK helped with the performance of experiments. EE performed ICP experiments in tomato in response to BR perturbations and performed sensitivity assays. HK performed ICP analysis in Arabidopsis, sensitivity assays, and prepared material for BR measurements. DT measured BR compounds. GH performed some of the statistical analysis. AC-P helped with the generation of bzr1 tomato stable mutants. CM generated the phylogenetic maps. JNM and SS-G contributed to the design and supervision of the research. GSD, SS-G and SMB wrote the manuscript. All authors edited the manuscript. GSD and DJG contributed equally to this work. \n\nData availability. Our gene expression data are publicly available in GEO, under accession no. GSE214195. The R scripts used for RSA and root hair length analysis are provided at https://github.com/BradyLab/DemirerPhosphate. In addition to the data provided in the manuscript, images and other raw data can be accessed at this link: Demirer et al. (2023), Raw image data for \"Phosphate deprivation-induced changes in tomato are mediated by an interaction between brassinosteroid signalling and zinc\", Dryad, Dataset, https://doi.org/10.25338/B8V656. \n\nCompeting interests: None declared.\n\n

Supplemental Material - nph19007-sup-0001-figs_s1-s18.pdf

In Press - New_Phytologist_-_2023_-_Demirer_-_Phosphate_deprivation\u2010induced_changes_in_tomato_are_mediated_by_an_interaction_between.pdf

", "abstract": "Inorganic phosphate (Pi) is a necessary macronutrient for basic biological processes. Plants modulate their root system architecture (RSA) and cellular processes to adapt to Pi deprivation albeit with a growth penalty. Excess application of Pi fertilizer, on the contrary, leads to eutrophication and has a negative environmental impact. \n\nWe compared RSA, root hair elongation, acid phosphatase activity, metal ion accumulation, and brassinosteroid hormone levels of Solanum lycopersicum (tomato) and Solanum pennellii, which is a wild relative of tomato, under Pi sufficiency and deficiency conditions to understand the molecular mechanism of Pi deprivation response in tomato. \n\nWe showed that S. pennellii is partially insensitive to phosphate deprivation. Furthermore, it mounts a constitutive response under phosphate sufficiency. We demonstrate that activated brassinosteroid signaling through a tomato BZR1 ortholog gives rise to the same constitutive phosphate deficiency response, which is dependent on zinc overaccumulation. \n\nCollectively, these results reveal an additional strategy by which plants can adapt to phosphate starvation.", "date": "2023-07-05", "date_type": "published", "publication": "New Phytologist", "publisher": "Wiley", "id_number": "CaltechAUTHORS:20230628-332770500.18", "issn": "0028-646X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230628-332770500.18", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "US-Israel Binational Agricultural Research and Development Fund", "grant_number": "IS-4827\u201015" }, { "agency": "Howard Hughes Medical Institute (HHMI)" }, { "agency": "NSF", "grant_number": "IOS-1856749" }, { "agency": "NSF", "grant_number": "IOS-2119820" }, { "agency": "NSF", "grant_number": "IOS-1238243" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "European Research Council (ERC)", "grant_number": "727929" }, { "agency": "European Regional Development Fund", "grant_number": "CZ.02.1.01/0.0/0.0/16_019/0000738" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1111/nph.19007", "primary_object": { "basename": "New_Phytologist_-_2023_-_Demirer_-_Phosphate_deprivation\u2010induced_changes_in_tomato_are_mediated_by_an_interaction_between.pdf", "url": "https://authors.library.caltech.edu/records/ys655-amx52/files/New_Phytologist_-_2023_-_Demirer_-_Phosphate_deprivation\u2010induced_changes_in_tomato_are_mediated_by_an_interaction_between.pdf" }, "related_objects": [ { "basename": "nph19007-sup-0001-figs_s1-s18.pdf", "url": "https://authors.library.caltech.edu/records/ys655-amx52/files/nph19007-sup-0001-figs_s1-s18.pdf" } ], "pub_year": "2023", "author_list": "Demirer, G\u00f6zde S.; Gibson, Donald J.; et al." }, { "id": "https://authors.library.caltech.edu/records/1k09k-srt54", "eprint_status": "archive", "datestamp": "2023-12-08 22:34:17", "lastmod": "2025-11-21 22:44:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Advancing electrocatalytic nitrogen fixation: insights from molecular systems", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry", "note": "

\u00a9 The Royal Society of Chemistry 2023.

\n\n

I am indebted to the many talented students and postdocs whose laboratory work, intellectual ideas, and rigorous analyses have shaped the trajectory of our research in N\u2082R catalysis, including electrocatalysis. A number of coworkers provided critical feedback to drafts of this perspective and deserve special mention. They are Emily Boyd, Dr Pablo Garrido-Barros, Dr Joseph Derosa, Dr Matthew Chalkley, Christian Johansen, and Enric Adillon (who also helped with the TOC graphic). I especially appreciate their catching some errors in thermodynamic values reported. While I alone own any additional thermodynamic fumbles to be found herein, there are fewer as a result of their input. I also thank the NIH (R01 GM-075757) and the DOE (DOE-0235032) for ongoing support of our iron-mediated nitrogen fixation work, and studies of electrocatalytic PCET mediators, respectively. I wish to acknowledge the Resnick Sustainability Institute at Caltech for enabling resources on Caltech's campus that have amplified the research we have been able to carry out.

", "abstract": "

Nitrogen fixation has a rich history within the inorganic chemistry community. In recent years attention has (re)focused on developing electrocatalytic systems capable of mediating the nitrogen reduction reaction (N\u2082RR). Well-defined molecular catalyst systems have much to offer in this context. This personal perspective summarizes recent progress from our laboratory at Caltech, pulling together lessons learned from a number of studies we have conducted, placing them within the broader context of thermodynamic efficiency and selectivity for the N\u2082RR. In particular, proton-coupled electron transfer (PCET) provides an attractive strategy to achieve enhanced efficiency for the multi-electron/proton reduction of N\u2082 to produce NH\u2083 (or NH\u2084\u207a), and electrocatalytic PCET (ePCET) via an ePCET mediator affords a promising means of mitigating HER such that the N\u2082RR can be achieved in a catalytic fashion.

", "date": "2023-07-01", "date_type": "published", "publication": "Faraday Discussions", "volume": "243", "publisher": "Royal Society of Chemistry", "pagerange": "450-472", "issn": "1359-6640", "official_url": "https://authors.library.caltech.edu/records/1k09k-srt54", "funders": { "items": [ { "grant_number": "GM-075757" }, { "grant_number": "DOE-0235032" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d3fd00017f", "pub_year": "2023", "author_list": "Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/m684g-6g048", "eprint_id": 121794, "eprint_status": "archive", "datestamp": "2023-08-22 21:17:25", "lastmod": "2023-10-20 15:50:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "de-Hoop-Maarten-V", "name": { "family": "de Hoop", "given": "Maarten V." }, "orcid": "0000-0002-6333-0379" }, { "id": "Kovachki-Nikola-B", "name": { "family": "Kovachki", "given": "Nikola B." }, "orcid": "0000-0002-3650-2972" }, { "id": "Nelsen-Nicholas-H", "name": { "family": "Nelsen", "given": "Nicholas H." }, "orcid": "0000-0002-8328-1199" }, { "id": "Stuart-A-M", "name": { "family": "Stuart", "given": "Andrew M." }, "orcid": "0000-0001-9091-7266" } ] }, "title": "Convergence Rates for Learning Linear Operators from Noisy Data", "ispublished": "pub", "full_text_status": "public", "keywords": "Applied Mathematics; Discrete Mathematics and Combinatorics; Statistics, Probability and Uncertainty; Modeling and Simulation; Statistics and Probability", "note": "\u00a9 2023 Society for Industrial and Applied Mathematics. \n\nFunding: The first author is supported by the Simons Foundation under the MATH + X program, U.S. Department\nof Energy, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division under grant DE-SC0020345, the National Science Foundation (NSF) under grant DMS-1815143, and the corporate members of the Geo-Mathematical Imaging Group at Rice University. The third author is supported by the NSF Graduate Research Fellowship Program under grant DGE-1745301. The fourth author is supported by NSF (grant DMS-1818977) and AFOSR (MURI award FA9550-20-1-0358---Machine Learning and Physics-Based Modeling and Simulation). The second, third, and fourth authors are supported by NSF (grant AGS-1835860) and ONR (grant N00014-19-1-2408). \n\nThe authors thank Kamyar Azizzadenesheli and Joel A. Tropp for\nhelpful discussions about statistical learning. The authors are also grateful to the associate editor and two anonymous referees for their helpful feedback. The computations presented in this paper were conducted on the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.\n\n

Published - 21m1442942.pdf

", "abstract": "This paper studies the learning of linear operators between infinite-dimensional Hilbert spaces. The training data comprises pairs of random input vectors in a Hilbert space and their noisy images under an unknown self-adjoint linear operator. Assuming that the operator is diagonalizable in a known basis, this work solves the equivalent inverse problem of estimating the operator's eigenvalues given the data. Adopting a Bayesian approach, the theoretical analysis establishes posterior contraction rates in the infinite data limit with Gaussian priors that are not directly linked to the forward map of the inverse problem. The main results also include learning-theoretic generalization error guarantees for a wide range of distribution shifts. These convergence rates quantify the effects of data smoothness and true eigenvalue decay or growth, for compact or unbounded operators, respectively, on sample complexity. Numerical evidence supports the theory in diagonal and nondiagonal settings.", "date": "2023-06-30", "date_type": "published", "publication": "SIAM/ASA Journal on Uncertainty Quantification", "volume": "11", "number": "2", "publisher": "Society for Industrial and Applied Mathematics", "pagerange": "480-513", "id_number": "CaltechAUTHORS:20230613-730765600.19", "issn": "2166-2525", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230613-730765600.19", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020345" }, { "agency": "NSF", "grant_number": "DMS-1815143" }, { "agency": "Rice University" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "DMS-1818977" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-20-1-0358" }, { "agency": "NSF", "grant_number": "AGS-1835860" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-19-1-2408" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1137/21m1442942", "primary_object": { "basename": "21m1442942.pdf", "url": "https://authors.library.caltech.edu/records/m684g-6g048/files/21m1442942.pdf" }, "pub_year": "2023", "author_list": "de Hoop, Maarten V.; Kovachki, Nikola B.; et al." }, { "id": "https://authors.library.caltech.edu/records/aqptv-k3b45", "eprint_id": 122452, "eprint_status": "archive", "datestamp": "2023-08-22 21:12:37", "lastmod": "2024-01-19 20:37:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cagan-David-A", "name": { "family": "Cagan", "given": "David A." }, "orcid": "0000-0002-4719-2789" }, { "id": "B\u00edm-Daniel", "name": { "family": "B\u00edm", "given": "Daniel" }, "orcid": "0000-0003-3100-4293" }, { "id": "McNicholas-Brendon-J", "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Kazmierczak-Nathanael-P", "name": { "family": "Kazmierczak", "given": "Nathanael P." }, "orcid": "0000-0002-7822-6769" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Photogenerated Ni(I)\u2013Bipyridine Halide Complexes: Structure\u2013Function Relationships for Competitive C(sp\u00b2)\u2013Cl Oxidative Addition and Dimerization Reactivity Pathways", "ispublished": "pub", "full_text_status": "public", "keywords": "Inorganic Chemistry; Physical and Theoretical Chemistry", "note": "\u00a9 2023 American Chemical Society. \n\nD.A.C. is a National Science Foundation Graduate Research Fellow (DGE-1745301) and is supported by a National Academies of Science, Engineering, and Medicine Ford Foundation Predoctoral Fellowship. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 883987 (D.B.). N.P.K. acknowledges support from the Hertz Fellowship and from the National Science Foundation Graduate Research Fellowship under Grant No. DGE1745301. The Caltech EPR facility acknowledges support from the Beckman Institute and the Dow Next Generation Educator Fund. Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R35-GM142595). The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. \n\nAuthor Contributions: D.A.C. and D.B. are co-first authors. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1905678.pdf

Supplemental Material - ic3c00917_si_001.pdf

Supplemental Material - ic3c00917_si_002.zip

", "abstract": "
\n

We report the facile photochemical generation of a library of Ni(I)–bpy halide complexes (Ni(I)(Rbpy)X (R = t-Bu, H, MeOOC; X = Cl, Br, I) and benchmark their relative reactivity toward competitive oxidative addition and off-cycle dimerization pathways. Structure–function relationships between the ligand set and reactivity are developed, with particular emphasis on rationalizing previously uncharacterized ligand-controlled reactivity toward high energy and challenging C(sp2)–Cl bonds. Through a dual Hammett and computational analysis, the mechanism of the formal oxidative addition is found to proceed through an SNAr-type pathway, consisting of a nucleophilic two-electron transfer between the Ni(I) 3d(z2) orbital and the Caryl–Cl σ* orbital, which contrasts the mechanism previously observed for activation of weaker C(sp2)–Br/I bonds. The bpy substituent provides a strong influence on reactivity, ultimately determining whether oxidative addition or dimerization even occurs. Here, we elucidate the origin of this substituent influence as arising from perturbations to the effective nuclear charge (Zeff) of the Ni(I) center. Electron donation to the metal decreases Zeff, which leads to a significant destabilization of the entire 3d orbital manifold. Decreasing the 3d(z2) electron binding energies leads to a powerful two-electron donor to activate strong C(sp2)–Cl bonds. These changes also prove to have an analogous effect on dimerization, with decreases in Zeff leading to more rapid dimerization. Ligand-induced modulation of Zeff and the 3d(z2) orbital energy is thus a tunable target by which the reactivity of Ni(I) complexes can be altered, providing a direct route to stimulate reactivity with even stronger C–X bonds and potentially unveiling new ways to accomplish Ni-mediated photocatalytic cycles.

\n
", "date": "2023-06-19", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "62", "number": "24", "publisher": "American Chemical Society", "pagerange": "9538-9551", "id_number": "CaltechAUTHORS:20230725-856902000.17", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-856902000.17", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "National Academies of Science, Engineering, and Medicine" }, { "agency": "Marie Curie Fellowship", "grant_number": "883987" }, { "agency": "Fannie and John Hertz Foundation" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "NIH", "grant_number": "R35-GM142595" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Ford Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.3c00917", "pmcid": "PMC10330939", "primary_object": { "basename": "nihms-1905678.pdf", "url": "https://authors.library.caltech.edu/records/aqptv-k3b45/files/nihms-1905678.pdf" }, "related_objects": [ { "basename": "ic3c00917_si_001.pdf", "url": "https://authors.library.caltech.edu/records/aqptv-k3b45/files/ic3c00917_si_001.pdf" }, { "basename": "ic3c00917_si_002.zip", "url": "https://authors.library.caltech.edu/records/aqptv-k3b45/files/ic3c00917_si_002.zip" } ], "pub_year": "2023", "author_list": "Cagan, David A.; B\u00edm, Daniel; et al." }, { "id": "https://authors.library.caltech.edu/records/836kq-twz22", "eprint_id": 121910, "eprint_status": "archive", "datestamp": "2023-08-22 21:11:38", "lastmod": "2023-10-23 20:22:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Dunne-Kieran-B-J", "name": { "family": "Dunne", "given": "Kieran B. J." }, "orcid": "0000-0003-0995-7629" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Sediment Entrainment and Slump Blocks Limit Permafrost Riverbank Erosion", "ispublished": "pub", "full_text_status": "public", "keywords": "General Earth and Planetary Sciences; Geophysics", "note": "\u00a9 2023 The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. \n\nThe authors would like to thank the Tribal Council and residents of Beaver, AK for access to their land and logistical support during fieldwork, in particular Liz Blackbird, Kody Vanderpool, Clinton Wiehl, Richard J. Williams, and Paul Williams Jr. We thank Rain Blankenship, Hannah Dion-Kirshner, Emily Geyman, Yutian Ke, John Magyar, Edda Mutter, Justin Nghiem, Jocelyn Reahl, Emily Seelen, Isabel Smith, A. Joshua West, and Lisa Winter for their assistance during fieldwork and two anonymous reviewers, whose recommendations greatly improved the manuscript. The authors acknowledge funding from NSF Awards 2127442, 2031532, and 2053009, Caltech's Resnick Sustainability Institute, and the National Defense Science and Engineering Graduate Fellowship. \n\nData Availability Statement. Soil bulk density and water content data were downloaded from https://doi.org/10.25675/10217/187212. Data for ground temperature were downloaded for site ID US O-82 from the Global Terrestrial Network for Permafrost (GTN-P) Database at http://gtnpdatabase.org/boreholes. Yukon River temperature and discharge data were downloaded from https://waterdata.usgs.gov/monitoring-location/15565447/ and https://waterdata.usgs.gov/monitoring-location/15453500/. Model code was written in Matlab R2022a under an academic license to the California Institute of Technology and code to run the model is available on Zenodo at https://doi.org/10.5281/zenodo.7958708. \n\nThe authors declare no conflicts of interest relevant to this study.\n\n

Published - Geophysical_Research_Letters_-_2023_-_Douglas_-_Sediment_Entrainment_and_Slump_Blocks_Limit_Permafrost_Riverbank_Erosion.pdf

Supplemental Material - 2023gl102974-sup-0001-supporting_information_si-s01.pdf

", "abstract": "Climatic warming and permafrost thaw are predicted to increase Arctic riverbank erosion, threatening communities and accelerating sediment, carbon and nutrient cycling between rivers and floodplains. Existing theory assumes that pore-ice thaw sets riverbank erosion rates, but overpredicts observed erosion rates by orders of magnitude. Here, we developed a simple model that predicts more modest rates due to a sediment-entrainment limitation and riverbank armoring by slump blocks. Results show that during times of thaw-limited erosion, the river rapidly erodes permafrost and undercuts its banks, consistent with previous work. However, overhanging banks generate slump blocks that must thaw and erode by sediment entrainment. Sediment entrainment can limit bank and slump block erosion rates, producing seasonally averaged rates more consistent with observations. Importantly, entrainment-limited riverbank erosion does not depend on water temperature, indicating that decadal erosion rates may be less sensitive to warming than predicted previously.", "date": "2023-06-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "50", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2023GL102974", "id_number": "CaltechAUTHORS:20230615-812756000.4", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230615-812756000.4", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-2053009" }, { "agency": "NSF", "grant_number": "EAR-2031532" }, { "agency": "NSF", "grant_number": "RISE-2127442" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2023gl102974", "primary_object": { "basename": "2023gl102974-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/836kq-twz22/files/2023gl102974-sup-0001-supporting_information_si-s01.pdf" }, "related_objects": [ { "basename": "Geophysical_Research_Letters_-_2023_-_Douglas_-_Sediment_Entrainment_and_Slump_Blocks_Limit_Permafrost_Riverbank_Erosion.pdf", "url": "https://authors.library.caltech.edu/records/836kq-twz22/files/Geophysical_Research_Letters_-_2023_-_Douglas_-_Sediment_Entrainment_and_Slump_Blocks_Limit_Permafrost_Riverbank_Erosion.pdf" } ], "pub_year": "2023", "author_list": "Douglas, Madison M.; Dunne, Kieran B. J.; et al." }, { "id": "https://authors.library.caltech.edu/records/209qm-2my05", "eprint_id": 122439, "eprint_status": "archive", "datestamp": "2023-11-30 17:14:21", "lastmod": "2025-09-27 00:32:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Du-Jiajun", "name": { "family": "Du", "given": "Jiajun" }, "orcid": "0000-0003-2693-834X" }, { "id": "Tao-Xuecheng", "name": { "family": "Tao", "given": "Xuecheng" }, "orcid": "0000-0003-2907-3839" }, { "id": "Begu\u0161i\u0107-Tomislav", "name": { "family": "Begu\u0161i\u0107", "given": "Tomislav" }, "orcid": "0000-0002-7942-4134" }, { "id": "Wei-Lu", "name": { "family": "Wei", "given": "Lu" }, "orcid": "0000-0001-9170-2283" } ] }, "title": "Computational Design of Molecular Probes for Electronic Preresonance Raman Scattering Microscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Surfaces, Coatings and Films; Physical and Theoretical Chemistry", "note": "\u00a9 2023 American Chemical Society. \n\nL.W. acknowledges support from NIH Director's New Innovator Award (GM140919). T.B. acknowledges financial support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship (Grant Number P2ELP2-199757). We thank Dr. Martin J. Schnermann for sharing the FC10 dye. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. \n\nAuthor Contributions: J.D. and X.T. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - jp3c00699_si_001.pdf

", "abstract": "Recently developed electronic preresonance stimulated Raman scattering (epr-SRS) microscopy, in which the Raman signal of a dye is significantly boosted by setting the incident laser frequency near the electronic excitation energy, has pushed the sensitivity of SRS microscopy close to that offered by confocal fluorescence microscopy. Prominently, the maintained narrow line-width of epr-SRS also offers high multiplexity that breaks the \"color barrier\" in optical microscopy. However, detailed understanding of the fundamental mechanism in these epr-SRS dyes still remains elusive. Here, we combine experiments with theoretical modeling to investigate the structure\u2013function relationship, aiming to facilitate the design of new probes and expanding epr-SRS palettes. Our ab initio approach employing the displaced harmonic oscillator (DHO) model provides a consistent agreement between simulated and experimental SRS intensities of various triple-bond bearing epr-SRS probes with distinct scaffolds. We further review two popular approximate expressions for epr-SRS, namely the short-time and Albrecht A-term equations, and compare them to the DHO model. Overall, the theory allows us to illustrate how the observed intensity differences between molecular scaffolds stem from the coupling strength between the electronic excitation and the targeted vibrational mode, leading to a general design strategy for highly sensitive next-generation vibrational imaging probes.", "date": "2023-06-08", "date_type": "published", "publication": "Journal of Physical Chemistry B", "volume": "127", "number": "22", "publisher": "American Chemical Society", "pagerange": "4979-4988", "id_number": "CaltechAUTHORS:20230725-856834000.3", "issn": "1520-6106", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-856834000.3", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM140919" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2ELP2-199757" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Chemistry-and-Chemical-Engineering" } ] }, "doi": "10.1021/acs.jpcb.3c00699", "pmcid": "PMC10676804", "primary_object": { "basename": "nihms-1943187.pdf", "url": "https://authors.library.caltech.edu/records/209qm-2my05/files/nihms-1943187.pdf" }, "related_objects": [ { "basename": "jp3c00699_si_001.pdf", "url": "https://authors.library.caltech.edu/records/209qm-2my05/files/jp3c00699_si_001.pdf" } ], "pub_year": "2023", "author_list": "Du, Jiajun; Tao, Xuecheng; et al." }, { "id": "https://authors.library.caltech.edu/records/eg3wd-7mj61", "eprint_id": 121759, "eprint_status": "archive", "datestamp": "2023-11-30 17:44:40", "lastmod": "2025-09-27 00:13:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Flesch-Kaylin-N", "name": { "family": "Flesch", "given": "Kaylin N." }, "orcid": "0000-0002-8582-2614" }, { "id": "Cusumano-Alexander-Q", "name": { "family": "Cusumano", "given": "Alexander Q." }, "orcid": "0000-0002-2914-2008" }, { "id": "Chen-Peng-Jui", "name": { "family": "Chen", "given": "Peng-Jui" }, "orcid": "0000-0002-3594-0081" }, { "id": "Strong-Christian-Santiago", "name": { "family": "Strong", "given": "Christian Santiago" } }, { "id": "Sardini-Stephen-R", "name": { "family": "Sardini", "given": "Stephen R." }, "orcid": "0000-0003-3643-4655" }, { "id": "Du-Yun-Emily", "name": { "family": "Du", "given": "Yun E." } }, { "id": "Bartberger-Michael-D", "name": { "family": "Bartberger", "given": "Michael D." }, "orcid": "0000-0002-5167-3139" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Divergent Catalysis: Catalytic Asymmetric [4+2] Cycloaddition of Palladium Enolates", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "

\u00a9 2023 American Chemical Society. This publication is licensed under CC-BY 4.0. The NIH-NIGMS (R35GM145239), Heritage Medical Research Investigators Program, and Caltech are thanked for the support of our research program. The authors thank the Caltech High Performance Computing Center for support. The authors thank Dr. David VanderVelde (Caltech) for NMR expertise, Dr. Mona Shagholi (Caltech) for mass spectrometry assistance, and Dr. Scott Virgil (Caltech) for instrumentation and SFC assistance. P.C. and C.S.S. would like to thank the NSF GRFP for funding. W.A.G. thanks the NSF (CBET-2005250) for support. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation. This manuscript is dedicated to the memory of Jiro Tsuji (1927\u20132022). Author Contributions. K.N.F. and A.Q.C. contributed equally. The authors declare no competing financial interest.

", "abstract": "An asymmetric decarboxylative [4+2] cycloaddition from a catalytically generated chiral Pd enolate was developed, forging four contiguous stereocenters in a single transformation. This was achieved through a strategy termed divergent catalysis, wherein departure from a known catalytic cycle enables novel reactivity of a targeted intermediate prior to re-entry into the original cycle. Mechanistic studies including quantum mechanics calculations, Eyring analysis, and KIE studies offer insight into the reaction mechanism.", "date": "2023-05-24", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "145", "number": "20", "publisher": "American Chemical Society", "pagerange": "11301-11310", "id_number": "CaltechAUTHORS:20230607-310749000.5", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230607-310749000.5", "funders": { "items": [ { "agency": "NIH", "grant_number": "R35GM145239" }, { "agency": "Heritage Medical Research Institute" }, { "agency": "NSF", "grant_number": "CBET-2005250" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "1569", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Heritage-Medical-Research-Institute" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Chemistry-and-Chemical-Engineering" } ] }, "doi": "10.1021/jacs.3c02104", "pmcid": "PMC10388310", "primary_object": { "basename": "ja3c02104.pdf", "url": "https://authors.library.caltech.edu/records/eg3wd-7mj61/files/ja3c02104.pdf" }, "related_objects": [ { "basename": "ja3c02104_si_002.zip", "url": "https://authors.library.caltech.edu/records/eg3wd-7mj61/files/ja3c02104_si_002.zip" }, { "basename": "ja3c02104_si_003.xlsx", "url": "https://authors.library.caltech.edu/records/eg3wd-7mj61/files/ja3c02104_si_003.xlsx" }, { "basename": "ja3c02104_si_001.pdf", "url": "https://authors.library.caltech.edu/records/eg3wd-7mj61/files/ja3c02104_si_001.pdf" } ], "pub_year": "2023", "author_list": "Flesch, Kaylin N.; Cusumano, Alexander Q.; et al." }, { "id": "https://authors.library.caltech.edu/records/2b41a-r1s24", "eprint_id": 122124, "eprint_status": "archive", "datestamp": "2023-08-20 16:53:24", "lastmod": "2025-11-14 00:31:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Long-Feng", "name": { "family": "Long", "given": "Feng" }, "orcid": "0000-0002-7607-719X" }, { "id": "Ren-Bin-B", "name": { "family": "Ren", "given": "Bin B." }, "orcid": "0000-0003-1698-9696" }, { "id": "Wallack-Nicole-L", "name": { "family": "Wallack", "given": "Nicole L." }, "orcid": "0000-0003-0354-0187" }, { "name": { "family": "Harsono", "given": "Daniel" }, "orcid": "0000-0001-6307-4195" }, { "name": { "family": "Herczeg", "given": "Gregory J." }, "orcid": "0000-0002-7154-6065" }, { "name": { "family": "Pinilla", "given": "Paola" }, "orcid": "0000-0001-8764-1780" }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "name": { "family": "Liu", "given": "Michael C." }, "orcid": "0000-0003-2232-7664" }, { "name": { "family": "Andrews", "given": "Sean M." }, "orcid": "0000-0003-2253-2270" }, { "name": { "family": "Bai", "given": "Xue-Ning" }, "orcid": "0000-0001-6906-9549" }, { "name": { "family": "Cabrit", "given": "Sylvie" }, "orcid": "0000-0002-1593-3693" }, { "name": { "family": "Cieza", "given": "Lucas A." }, "orcid": "0000-0002-2828-1153" }, { "name": { "family": "Johnstone", "given": "Doug" }, "orcid": "0000-0002-6773-459X" }, { "name": { "family": "Leisenring", "given": "Jarron M." }, "orcid": "0000-0002-0834-6140" }, { "name": { "family": "Lodato", "given": "Giuseppe" }, "orcid": "0000-0002-2357-7692" }, { "name": { "family": "Liu", "given": "Yao" } }, { "name": { "family": "Manara", "given": "Carlo F." }, "orcid": "0000-0003-3562-262X" }, { "name": { "family": "Mulders", "given": "Gijs D." }, "orcid": "0000-0002-1078-9493" }, { "name": { "family": "Ragusa", "given": "Enrico" }, "orcid": "0000-0001-5378-7749" }, { "name": { "family": "Sallum", "given": "Steph" }, "orcid": "0000-0001-6871-6775" }, { "name": { "family": "Shi", "given": "Yangfan" }, "orcid": "0000-0001-9277-6495" }, { "name": { "family": "Tazzari", "given": "Marco" }, "orcid": "0000-0003-3590-5814" }, { "id": "Uyama-Taichi", "name": { "family": "Uyama", "given": "Taichi" }, "orcid": "0000-0002-6879-3030" }, { "name": { "family": "Wagner", "given": "Kevin" }, "orcid": "0000-0002-4309-6343" }, { "name": { "family": "Wilner", "given": "David J." }, "orcid": "0000-0003-1526-7587" }, { "id": "Xuan-Jerry-W", "name": { "family": "Xuan", "given": "Jerry W." }, "orcid": "0000-0002-6618-1137" } ] }, "title": "A Large Double-ring Disk Around the Taurus M Dwarf J04124068+2438157", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nF.L. thanks Rixin Li and Shangjia Zhang for insightful discussions. Support for F.L. was provided by NASA through the NASA Hubble Fellowship grant #HST-HF2-51512.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. F.L. and S.A. acknowledge funding support from the National Aeronautics and Space Administration under grant No. 17-XRP17 _ 2-0012 issued through the Exoplanets Research Program. D.H. is supported by Center for Informatics and Computation in Astronomy (CICA) grant and grant No. 110J0353I9 from the Ministry of Education of Taiwan. D.H. also acknowledges support from the National Science and Technology Council of Taiwan through grant No. 111B3005191. G.J.H and Y.S. are supported by grant 12173003 from the National Natural Science Foundation of China. G.D.M. acknowledges support from FONDECYT project 11221206, from ANID\u2014Millennium Science Initiative\u2014ICN12_009, and the ANID BASAL project FB210003. D.J. is supported by NRC Canada and by an NSERC Discovery Grant. Y.L. acknowledges the financial support by the Natural Science Foundation of China (grant No. 11973090). L.C. was supported by ANID through the Milennium Science Initiative Program (NCN2021_080) and the FONDECYT Grant 1211656. E.R. acknowledges financial support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 864965, PODCAST) C.F.M is funded by the European Union (ERC, WANDA, 101039452). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council Executive Agency. Neither the European Union nor the granting authority can be held responsible for them. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (PROTOPLANETS, grant agreement No. 101002188). This research was funded in part by the Gordon and Betty Moore Foundation through grant GBMF8550 to M. Liu. K.W. is supported by NASA through the NASA Hubble Fellowship grant HST- HF2-51472.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. J.L. acknowledges funding from JWST/NIRCam contract to the University of Arizona, NAS5-02105 This research is partially supported by NASA ROSES XRP, award 80NSSC19K0294. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. Part of the computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.\n\nThis paper makes use of the following ALMA data: ADS/JAO.ALMA#2019.1.00566.S. ALMA is a partnership of ESO (representing its member states), NSF (USA), and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. \n\nFacilities: ALMA - Atacama Large Millimeter Array, Keck II (NIRC2). - \n\nSoftware: emcee (Foreman-Mackey et al. 2013), CASA (CASA Team et al. 2022), pynrc (Leisenring et al. 2022), VIP (Gomez Gonzalez et al. 2017).\n\n

Published - Long_2023_ApJ_949_27.pdf

", "abstract": "Planet formation imprints signatures on the physical structures of disks. In this paper, we present high-resolution (\u223c50 mas, 8 au) Atacama Large Millimeter/submillimeter Array observations of 1.3 mm dust continuum and CO line emission toward the disk around the M3.5 star 2MASS J04124068+2438157. The dust disk consists of only two narrow rings at radial distances of 0.\"47 and 0.\"78 (\u223c70 and 116 au), with Gaussian \u03c3 widths of 5.6 and 8.5 au, respectively. The width of the outer ring is smaller than the estimated pressure scale height by \u223c25%, suggesting dust trapping in a radial pressure bump. The dust disk size, set by the location of the outermost ring, is significantly larger (by 3\u03c3) than other disks with similar millimeter luminosity, which can be explained by an early formation of local pressure bump to stop radial drift of millimeter dust grains. After considering the disk's physical structure and accretion properties, we prefer planet\u2013disk interaction over dead zone or photoevaporation models to explain the observed dust disk morphology. We carry out high-contrast imaging at the L' band using Keck/NIRC2 to search for potential young planets, but do not identify any source above 5\u03c3. Within the dust gap between the two rings, we reach a contrast level of \u223c7 mag, constraining the possible planet below \u223c2\u20134 M_(Jup). Analyses of the gap/ring properties suggest that an approximately Saturn-mass planet at \u223c90 au is likely responsible for the formation of the outer ring, which can potentially be revealed with JWST.", "date": "2023-05-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "949", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 27", "id_number": "CaltechAUTHORS:20230705-940527100.4", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230705-940527100.4", "funders": { "items": [ { "agency": "NASA Hubble Fellowship", "grant_number": "HST-HF2-51512.001-A" }, { "agency": "NASA", "grant_number": "NAS5-26555" }, { "agency": "NASA", "grant_number": "17-XRP17_2-0012" }, { "agency": "Ministry of Education (Taipei)", "grant_number": "110J0353I9" }, { "agency": "National Science and Technology Council (Taipei)", "grant_number": "111B3005191" }, { "agency": "National Natural Science Foundation of China", "grant_number": "12173003" }, { "agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)", "grant_number": "11221206" }, { "agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)", "grant_number": "ICN12_009" }, { "agency": "Agencia Nacional de Investigaci\u00f3n y Desarrollo (ANID)", "grant_number": "FB210003" }, { "agency": "National Research Council of Canada" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "National Science Foundation of China", "grant_number": "11973090" }, { "agency": "Agencia Estatal de Investigaci\u00f3n", "grant_number": "NCN2021_080" }, { "agency": "Fondo Nacional de Desarrollo Cient\u00edfico y Tecnol\u00f3gico (FONDECYT)", "grant_number": "1211656" }, { "agency": "European Research Council (ERC)", "grant_number": "864965" }, { "agency": "European Research Council (ERC)", "grant_number": "101039452" }, { "agency": "European Research Council (ERC)", "grant_number": "101002188" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF8550" }, { "agency": "NASA Hubble Fellowship", "grant_number": "HST-HF2-51472.001-A" }, { "agency": "NASA", "grant_number": "NAS5-02105" }, { "agency": "NASA", "grant_number": "80NSSC19K0294" }, { "agency": "W. M. Keck Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Infrared-Processing-and-Analysis-Center-(IPAC)" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/1538-4357/acc843", "primary_object": { "basename": "Long_2023_ApJ_949_27.pdf", "url": "https://authors.library.caltech.edu/records/2b41a-r1s24/files/Long_2023_ApJ_949_27.pdf" }, "pub_year": "2023", "author_list": "Long, Feng; Ren, Bin B.; et al." }, { "id": "https://authors.library.caltech.edu/records/g438j-zye19", "eprint_id": 121600, "eprint_status": "archive", "datestamp": "2023-08-22 20:58:37", "lastmod": "2025-11-22 02:03:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Caron-Huot-Simon", "name": { "family": "Caron-Huot", "given": "Simon" }, "orcid": "0000-0002-7005-9652" }, { "id": "Li-Yue-Zhou", "name": { "family": "Li", "given": "Yue-Zhou" }, "orcid": "0000-0002-3982-4838" }, { "id": "Parra-Martinez-Julio", "name": { "family": "Parra-Martinez", "given": "Julio" }, "orcid": "0000-0003-0178-1569" }, { "id": "Simmons-Duffin-D", "name": { "family": "Simmons-Duffin", "given": "David" }, "orcid": "0000-0002-2937-9515" } ] }, "title": "Causality constraints on corrections to Einstein gravity", "ispublished": "pub", "full_text_status": "public", "keywords": "Nuclear and High Energy Physics", "note": "\u00a9 2023 The Authors. This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited. \n\nArticle funded by SCOAP3. \n\nWe thank Robert Brandenberger, Clifford Cheung, Cyuan-Han Chang, Jim Cline, Claudia de Rham, Yanky Landau, Dalimil Mazac, Leonardo Rastelli, Katelin Schutz, Andrew Tolley and Sasha Zhiboedov for discussions. DSD, SCH and YZL are supported by the Simons Foundation through the Simons Collaboration on the Nonperturbative Bootstrap. DSD is also supported by a DOE Early Career Award under grant no. DE-SC0019085. SCH is also supported by the Canada Research Chair program and the Sloan Foundation. JPM is supported by the DOE under grant no. DE-SC0011632. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported\nby Resnick Sustainability Institute at the California Institute of Technology. Some figures were made using the TikZ-Feynman package [82].\n\n

Published - JHEP05_2023_122.pdf

", "abstract": "We study constraints from causality and unitarity on 2 \u2192 2 graviton scattering in four-dimensional weakly-coupled effective field theories. Together, causality and unitarity imply dispersion relations that connect low-energy observables to high-energy data. Using such dispersion relations, we derive two-sided bounds on gravitational Wilson coefficients in terms of the mass M of new higher-spin states. Our bounds imply that gravitational interactions must shut off uniformly in the limit G \u2192 0, and prove the scaling with M expected from dimensional analysis (up to an infrared logarithm). We speculate that causality, together with the non-observation of gravitationally-coupled higher spin states at colliders, severely restricts modifications to Einstein gravity that could be probed by experiments in the near future.", "date": "2023-05-18", "date_type": "published", "publication": "Journal of High Energy Physics", "volume": "2023", "number": "5", "publisher": "Springer", "pagerange": "Art. No. 122", "id_number": "CaltechAUTHORS:20230530-441187700.14", "issn": "1029-8479", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230530-441187700.14", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019085" }, { "agency": "Canada Research Chairs Program" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011632" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "SCOAP3" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.1007/jhep05(2023)122", "primary_object": { "basename": "JHEP05_2023_122.pdf", "url": "https://authors.library.caltech.edu/records/g438j-zye19/files/JHEP05_2023_122.pdf" }, "pub_year": "2023", "author_list": "Caron-Huot, Simon; Li, Yue-Zhou; et al." }, { "id": "https://authors.library.caltech.edu/records/mpc7a-e4488", "eprint_id": 121456, "eprint_status": "archive", "datestamp": "2023-08-22 20:56:52", "lastmod": "2025-11-22 02:10:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roberts-Gregory-D", "name": { "family": "Roberts", "given": "Gregory" } }, { "id": "Ballew-Conner", "name": { "family": "Ballew", "given": "Conner" }, "orcid": "0000-0003-4854-8342" }, { "id": "Zheng-Tianzhe", "name": { "family": "Zheng", "given": "Tianzhe" }, "orcid": "0000-0001-7058-5196" }, { "id": "Garcia-Juan-C", "name": { "family": "Garcia", "given": "Juan C." } }, { "id": "Camayd-Mu\u00f1oz-Sarah", "name": { "family": "Camayd-Mu\u00f1oz", "given": "Sarah" }, "orcid": "0000-0002-1203-3083" }, { "id": "Hon-Philip-W-C", "name": { "family": "Hon", "given": "Philip W. C." }, "orcid": "0000-0001-7507-4571" }, { "id": "Faraon-A", "name": { "family": "Faraon", "given": "Andrei" }, "orcid": "0000-0002-8141-391X" } ] }, "title": "3D-patterned inverse-designed mid-infrared metaoptics", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary", "note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nWe thank the staff at Northrop Grumman for allowing us to carry out mid-infrared measurements at their facility with their equipment and to Orrin Kigner for assistance with coordination as well as measurement advice. Further, we acknowledge Chase Ellis from the U.S. Naval Research Laboratory and Professor Joe Tischler from University of Oklahoma for initial measurement and fabrication assistance as well as continued advice on the experimental setup and fabrication parameters. We thank Malina Strugaru for work on characterizing and verifying aspects of Nanoscribe fabrication, and Dr. Amir Arbabi, Dr. Oscar Bruno, Dr. Hyounghan Kwon and Ian Foo for helpful conversations and advice. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. This work was funded by Defense Advanced Research Projects Agency (HR00111720035), Rothenberg Innovation Initiative (RI2), Clinard Innovation Fund at Caltech and Army Research Office (W911NF-22-1-0097). \n\nContributions. G.R., S.C.M., and A.F. conceived the project. G.R. carried out optimization, fabrication, and measurement of devices in the manuscript with input from other authors. C.B. consulted and provided critical feedback on optimization and measurement techniques and data analysis. T.Z. consulted on fabrication and optimization methods. J.C.G. and P.W.C.H. provided help with design and construction of the experimental setup as well as invaluable consultation on measurement results, as well as hosted G.R. for measurements on many occasions at Northrop Grumman. G.R. prepared the manuscript with input from all authors. \n\nData availability. Data to support the conclusions in the manuscript can be provided on request. \n\nCompeting interests. The authors have filed the following patents related to this work: Color and multi-spectral image sensor based on 3d engineered material (US20200124866A1) Broadband Polarization Splitting Based on Volumetric Meta-Optics (US20220004016) CMOS color image sensors with metamaterial color splitting (US11239276B2) There are no other competing interests.\n\n

Published - 41467_2023_Article_38258.pdf

Supplemental Material - 41467_2023_38258_MOESM1_ESM.pdf

", "abstract": "Modern imaging systems can be enhanced in efficiency, compactness, and application through the introduction of multilayer nanopatterned structures for manipulation of light based on its fundamental properties. High transmission multispectral imaging is elusive due to the commonplace use of filter arrays which discard most of the incident light. Further, given the challenges of miniaturizing optical systems, most cameras do not leverage the wealth of information in polarization and spatial degrees of freedom. Optical metamaterials can respond to these electromagnetic properties but have been explored primarily in single-layer geometries, limiting their performance and multifunctional capacity. Here we use advanced two-photon lithography to realize multilayer scattering structures that achieve highly nontrivial optical transformations intended to process light just before it reaches a focal plane array. Computationally optimized multispectral and polarimetric sorting devices are fabricated with submicron feature sizes and experimentally validated in the mid-infrared. A final structure shown in simulation redirects light based on its angular momentum. These devices demonstrate that with precise 3-dimensional nanopatterning, one can directly modify the scattering properties of a sensor array to create advanced imaging systems.", "date": "2023-05-13", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2768", "id_number": "CaltechAUTHORS:20230519-1694000.16", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230519-1694000.16", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "HR00111720035" }, { "agency": "Gary Clinard Innovation Fund" }, { "agency": "Rothenberg Innovation Initiative (RI2)" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-22-1-0097" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-023-38258-2", "pmcid": "PMC10183040", "primary_object": { "basename": "41467_2023_Article_38258.pdf", "url": "https://authors.library.caltech.edu/records/mpc7a-e4488/files/41467_2023_Article_38258.pdf" }, "related_objects": [ { "basename": "41467_2023_38258_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/mpc7a-e4488/files/41467_2023_38258_MOESM1_ESM.pdf" } ], "pub_year": "2023", "author_list": "Roberts, Gregory; Ballew, Conner; et al." }, { "id": "https://authors.library.caltech.edu/records/mxr3m-q3p21", "eprint_id": 121301, "eprint_status": "archive", "datestamp": "2023-08-22 20:56:23", "lastmod": "2025-11-22 03:59:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Watkins-Nicholas-B", "name": { "family": "Watkins", "given": "Nicholas B." }, "orcid": "0000-0001-7251-9387" }, { "id": "Schiffer-Zachary-J", "name": { "family": "Schiffer", "given": "Zachary J." }, "orcid": "0000-0001-6069-8613" }, { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Musgrave-Charles-B-III", "name": { "family": "Musgrave", "given": "Charles B., III" }, "orcid": "0000-0002-3432-0817" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Hydrodynamics Change Tafel Slopes in Electrochemical CO\u2082 Reduction on Copper", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "\u00a9 2023 The Authors. Published by American Chemical Society. Attribution 4.0 International (CC BY 4.0).\n\nThis material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. The Resnick Sustainability Institute at Caltech is acknowledged for its support of enabling infrastructure and facilities. We thank Dr. Ian Sullivan for many productive conversations and Annette Boehme for initial insights into COMSOL calculations of the cells investigated. \n\nN.B.W. and Z.J.S. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Published - acsenergylett.3c00442.pdf

Supplemental Material - nz3c00442_si_001.pdf

", "abstract": "The hydrodynamics of electrochemical CO\u2082 reduction (CO\u2082R) systems is an insufficiently investigated area of research that has broad implications on catalyst activity and selectivity. While most previous reports are limited to laminar and CO\u2082-sparged systems, herein we address a wide range of hydrodynamics via electrolyte recirculation systems. We find that increased hydrodynamics at the electrode surface results directly in changes to the ethylene and methane Tafel slopes, demonstrating that mass transport is on equal footing with catalyst active sites in determining reaction mechanisms and the ensuing product distribution. Mass transport is traditionally considered to be in the purview of systems-level engineering, yet the present work shows that CO\u2082R mechanistic work must be considered in the context of the mass transport conditions. We extend our analysis to organic coatings, demonstrating that the films shield the active sites from variability in hydrodynamics and increase the residence time of CO so that it may be further reduced to desirable products.", "date": "2023-05-12", "date_type": "published", "publication": "ACS Energy Letters", "volume": "8", "number": "5", "publisher": "American Chemical Society", "pagerange": "2185-2192", "id_number": "CaltechAUTHORS:20230502-856709200.5", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230502-856709200.5", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" } ] }, "other_numbering_system": { "items": [ { "id": "1567", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.3c00442", "primary_object": { "basename": "acsenergylett.3c00442.pdf", "url": "https://authors.library.caltech.edu/records/mxr3m-q3p21/files/acsenergylett.3c00442.pdf" }, "related_objects": [ { "basename": "nz3c00442_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mxr3m-q3p21/files/nz3c00442_si_001.pdf" } ], "pub_year": "2023", "author_list": "Watkins, Nicholas B.; Schiffer, Zachary J.; et al." }, { "id": "https://authors.library.caltech.edu/records/yw2sd-bmj62", "eprint_id": 122111, "eprint_status": "archive", "datestamp": "2023-08-22 20:50:16", "lastmod": "2023-10-23 20:30:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moure-Adrian", "name": { "family": "Moure", "given": "Adrian" }, "orcid": "0000-0001-9807-0039" }, { "id": "Jones-Nathan", "name": { "family": "Jones", "given": "Nathan" }, "orcid": "0000-0002-0911-4616" }, { "id": "Pawlak-Joshua", "name": { "family": "Pawlak", "given": "Joshua" }, "orcid": "0000-0001-6595-6378" }, { "id": "Meyer-Colin", "name": { "family": "Meyer", "given": "Colin" }, "orcid": "0000-0002-1209-1881" }, { "id": "Fu-Xiaojing-Ruby", "name": { "family": "Fu", "given": "Xiaojing" }, "orcid": "0000-0001-7120-704X" } ] }, "title": "A Thermodynamic Nonequilibrium Model for Preferential Infiltration and Refreezing of Melt in Snow", "ispublished": "pub", "full_text_status": "public", "keywords": "Water Science and Technology", "note": "\u00a9 2023. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nXF, AM and NJ acknowledge the support of the Resnick Sustainability Institute at California Institute of Technology and the National Science Foundation under Grant EAR-2243631. CM acknowledges support from the Heising-Simons Foundation (# 2020-1911) and the William H. Neukom Institute for Computational Science at Dartmouth College. JP ackowledges the support of the Caltech Summer Undergraduate Research Fellowship. The authors also acknowledge the insightful discussions with David DiCarlo, Marc Hesse, Dani Or, John Selker, Riley Culberg, Quirine Krol, Ian Hewitt, and Nicolas Leroux. AM, CM, and XF designed the study. AM and XF developed the model. AM implemented the model numerically and performed numerical simulations. NJ and JP helped with model validation against experimental data. AM, NJ, JP, CM, and XF analyzed the results and wrote the paper. XF secured funding for this project. \n\nData Availability Statement: Datasets for this research are available in Moure et al. (2023), and can be directly accessed at https://data.caltech.edu/records/w6zyq-wqw17.\n\n

Published - Water_Resources_Research_-_2023_-_Moure_-_A_Thermodynamic_Nonequilibrium_Model_for_Preferential_Infiltration_and_Refreezing.pdf

Supplemental Material - 2022wr034035-sup-0001-supporting_information_si-s01.pdf

Supplemental Material - 2022wr034035-sup-0002-movie_si-s01.mp4

Supplemental Material - 2022wr034035-sup-0003-movie_si-s02.mp4

", "abstract": "The transport of meltwater through porous snow is a fundamental process in hydrology that remains poorly understood but essential for more robust predictions of how the cryosphere will respond under climate change. Here, we propose a continuum model that resolves the nonlinear coupling of preferential melt flow and the nonequilibrium thermodynamics of ice-melt phase change at the Darcy scale. We assume that the commonly observed unstable melt infiltration is due to the gravity fingering instability and capture it using the modified Richards equation, which is extended with a higher-order term in saturation. Our model accounts for changes in porosity and the thermal budget of the snowpack caused by melt refreezing at the continuum scale, based on a mechanistic estimate of the ice-water phase change kinetics formulated at the pore scale. We validate the model in 1D against field data and laboratory experiments of infiltration in snow and find generally good agreement. Compared to existing theory of stable melt infiltration, our 2D simulation results show that preferential infiltration delivers melt faster to deeper depths, and as a result, changes in porosity and temperature can occur at deeper parts of the snow. The simulations also capture the formation of vertical low porosity annulus known as ice pipes, which have been observed in the field but lack mechanistic understanding to date. Our results demonstrate how melt refreezing and unstable infiltration reshape the porosity structure of snow and impacts thermal and mass transport in highly nonlinear ways that are not captured by simpler models.", "date": "2023-05", "date_type": "published", "publication": "Water Resources Research", "volume": "59", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2022WR034035", "id_number": "CaltechAUTHORS:20230705-704041500.8", "issn": "0043-1397", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230705-704041500.8", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "EAR-2243631" }, { "agency": "Heising-Simons Foundation", "grant_number": "2020-1911" }, { "agency": "Dartmouth College" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2022wr034035", "primary_object": { "basename": "2022wr034035-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/yw2sd-bmj62/files/2022wr034035-sup-0001-supporting_information_si-s01.pdf" }, "related_objects": [ { "basename": "2022wr034035-sup-0002-movie_si-s01.mp4", "url": "https://authors.library.caltech.edu/records/yw2sd-bmj62/files/2022wr034035-sup-0002-movie_si-s01.mp4" }, { "basename": "2022wr034035-sup-0003-movie_si-s02.mp4", "url": "https://authors.library.caltech.edu/records/yw2sd-bmj62/files/2022wr034035-sup-0003-movie_si-s02.mp4" }, { "basename": "Water_Resources_Research_-_2023_-_Moure_-_A_Thermodynamic_Nonequilibrium_Model_for_Preferential_Infiltration_and_Refreezing.pdf", "url": "https://authors.library.caltech.edu/records/yw2sd-bmj62/files/Water_Resources_Research_-_2023_-_Moure_-_A_Thermodynamic_Nonequilibrium_Model_for_Preferential_Infiltration_and_Refreezing.pdf" } ], "pub_year": "2023", "author_list": "Moure, Adrian; Jones, Nathan; et al." }, { "id": "https://authors.library.caltech.edu/records/jqxmz-ke040", "eprint_id": 121911, "eprint_status": "archive", "datestamp": "2023-08-22 20:46:10", "lastmod": "2023-10-20 16:47:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Callies-J", "name": { "family": "Callies", "given": "J\u00f6rn" }, "orcid": "0000-0002-6815-1230" }, { "id": "Wu-Wenbo", "name": { "family": "Wu", "given": "Wenbo" }, "orcid": "0000-0002-6249-8065" }, { "id": "Peng-Shirui", "name": { "family": "Peng", "given": "Shirui" }, "orcid": "0000-0002-4616-4604" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" } ] }, "title": "Vertical-Slice Ocean Tomography With Seismic Waves", "ispublished": "pub", "full_text_status": "public", "keywords": "General Earth and Planetary Sciences; Geophysics", "note": "\u00a9 2023. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nThis material is based upon work supported by the Resnick Sustainability Institute and by the National Science Foundation under Grant OCE-2023161. \n\nThe views expressed in the paper are those of the authors and do not necessarily represent those of the CTBTO. \n\nData Availability Statement. The IMS hydrophone data are available directly from the CTBTO upon request and signing a confidentiality agreement to access the virtual Data Exploitation Centre (vDEC). All seismic data were downloaded through the IRIS Data Management Center (https://service.iris.edu/), including the seismic networks II (GSN; https://doi.org/10.7914/SN/II), MY, PS, and GE (https://doi.org/10.14470/TR560404). The Global Seismographic Network (GSN) is a cooperative scientific facility operated jointly by the Incorporated Research Institutions for Seismology (IRIS), the United States Geological Survey (USGS) and the National Science Foundation (NSF), under Cooperative Agreement EAR-1261681. The processing code is available at https://github.com/joernc/SOT.\n\n

Published - Geophysical_Research_Letters_-_2023_-_Callies_-_Vertical\u2010Slice_Ocean_Tomography_With_Seismic_Waves.pdf

Supplemental Material - 2023gl102881-sup-0001-supporting_information_si-s01.pdf

", "abstract": "Seismically generated sound waves that propagate through the ocean are used to infer temperature anomalies and their vertical structure in the deep East Indian Ocean. These T waves are generated by earthquakes off Sumatra and received by hydrophone stations off Diego Garcia and Cape Leeuwin. Between repeating earthquakes, a T wave's travel time changes in response to temperature anomalies along the wave's path. What part of the water column the travel time is sensitive to depends on the frequency of the wave, so measuring travel time changes at a few low frequencies constrains the vertical structure of the inferred temperature anomalies. These measurements reveal anomalies due to equatorial waves, mesoscale eddies, and decadal warming trends. By providing direct constraints on basin-scale averages with dense sampling in time, these data complement previous point measurements that alias local and transient temperature anomalies.", "date": "2023-04-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "50", "number": "8", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2023GL102881", "id_number": "CaltechAUTHORS:20230615-812761000.6", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230615-812761000.6", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "OCE\u20102023161" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" } ] }, "doi": "10.1029/2023gl102881", "primary_object": { "basename": "2023gl102881-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/jqxmz-ke040/files/2023gl102881-sup-0001-supporting_information_si-s01.pdf" }, "related_objects": [ { "basename": "Geophysical_Research_Letters_-_2023_-_Callies_-_Vertical\u2010Slice_Ocean_Tomography_With_Seismic_Waves.pdf", "url": "https://authors.library.caltech.edu/records/jqxmz-ke040/files/Geophysical_Research_Letters_-_2023_-_Callies_-_Vertical\u2010Slice_Ocean_Tomography_With_Seismic_Waves.pdf" } ], "pub_year": "2023", "author_list": "Callies, J\u00f6rn; Wu, Wenbo; et al." }, { "id": "https://authors.library.caltech.edu/records/9xpd4-15a70", "eprint_id": 121699, "eprint_status": "archive", "datestamp": "2023-08-22 20:45:55", "lastmod": "2025-11-22 02:35:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yin-Yi", "name": { "family": "Yin", "given": "Yi" }, "orcid": "0000-0003-4750-4997" }, { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Unequal exposure to heatwaves in Los Angeles: Impact of uneven green spaces", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2023 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). \n\nThis study is supported by NASA ECOSTRESS Science Team Project (grant no. 80NSSC20K0078). L.H. thanks the Caltech Resnick Sustainability Institute for supporting her Research Fellowship. \n\nY.Y. designed the research. L.H. and Y.Y. collected data and performed analysis. P.O.W. and C.F. contributed to the interpretation of the results. All authors contributed to the writing and editing of the manuscript. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. The ECOSTRESS data supporting this paper are available in the Caltech Data Repository; https://data.caltech.edu/records/esx93-qx576 (https://doi.org/10.22002/esx93-qx576). \n\nThe authors declare that they have no competing interests.\n\n

Published - sciadv.ade8501.pdf

Supplemental Material - sciadv.ade8501_sm.pdf

", "abstract": "Cities worldwide are experiencing record-breaking summer temperatures. Urban environments exacerbate extreme heat, resulting in not only the urban heat island but also intracity variations in heat exposure. Understanding these disparities is crucial to support equitable climate mitigation and adaptation efforts. We found persistent negative correlations between daytime land surface temperature (LST) and median household income across the Los Angeles metropolitan area based on Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station observations from 2018 to 2021. Lower evapotranspiration resulting from the unequal distribution of vegetation cover is a major factor leading to higher LST in low-income neighborhoods. Disparities worsen with higher regional mean surface temperature, with a $10,000 decrease in income leading to ~0.2\u00b0C LST increase at 20\u00b0C and up to ~0.7\u00b0C at 45\u00b0C. With more frequent and intense heat waves projected in the future, equitable mitigation measures, such as increasing surface albedo and tree cover in low-income neighborhoods, are necessary to address these disparities.", "date": "2023-04-28", "date_type": "published", "publication": "Science Advances", "volume": "9", "number": "17", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eade8501", "id_number": "CaltechAUTHORS:20230602-251907000.50", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230602-251907000.50", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC20K0078" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.ade8501", "pmcid": "PMC10146884", "primary_object": { "basename": "sciadv.ade8501.pdf", "url": "https://authors.library.caltech.edu/records/9xpd4-15a70/files/sciadv.ade8501.pdf" }, "related_objects": [ { "basename": "sciadv.ade8501_sm.pdf", "url": "https://authors.library.caltech.edu/records/9xpd4-15a70/files/sciadv.ade8501_sm.pdf" } ], "pub_year": "2023", "author_list": "Yin, Yi; He, Liyin; et al." }, { "id": "https://authors.library.caltech.edu/records/ekhvn-8sz05", "eprint_id": 121305, "eprint_status": "archive", "datestamp": "2023-08-22 20:44:51", "lastmod": "2025-11-22 01:44:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Can", "name": { "family": "Li", "given": "Can" }, "orcid": "0000-0001-8894-5110" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Chen-Xiaobo", "name": { "family": "Chen", "given": "Xiaobo" } }, { "id": "Zhang-Lihua", "name": { "family": "Zhang", "given": "Lihua" } }, { "id": "Sharma-Anju", "name": { "family": "Sharma", "given": "Anju" } }, { "id": "Jiang-Shaojie", "name": { "family": "Jiang", "given": "Shaojie" }, "orcid": "0000-0001-8692-0673" }, { "id": "Zhang-Hanlei", "name": { "family": "Zhang", "given": "Hanlei" }, "orcid": "0000-0001-6540-0556" }, { "id": "Zhou-Ming", "name": { "family": "Zhou", "given": "Ming" }, "orcid": "0000-0002-2708-0501" }, { "id": "Pan-Jinfong", "name": { "family": "Pan", "given": "Jinfong" } }, { "id": "Zhou-Guangwen", "name": { "family": "Zhou", "given": "Guangwen" }, "orcid": "0000-0002-9243-293X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Fang-Jiye", "name": { "family": "Fang", "given": "Jiye" }, "orcid": "0000-0003-3703-3204" } ] }, "title": "Improving Oxygen Reduction Performance of Surface-Layer-Controlled Pt\u2013Ni Nano-Octahedra via Gaseous Etching", "ispublished": "pub", "full_text_status": "public", "keywords": "Mechanical Engineering; Condensed Matter Physics; General Materials Science; General Chemistry; Bioengineering", "note": "\u00a9 2023 American Chemical Society. \n\nThis work was primarily supported by the National Science Foundation (NSF) under grant DMR-1808383. The theoretical work used the Extreme Science and Engineering Discovery Environment (XSEDE) for DFT calculations, which is supported by the NSF under grant ACI-1548562. W.A.G. is thankful for support by the NSF (CBET-2005250, program manager: Bob McCabe), S.K. acknowledges support from the Resnick Sustainability Institute at Caltech; X.C. and G.Z. are thankful for the financial support by the NSF under grant DMR-1905422. L.Z. acknowledges the use of TEM facilities for the structural characterizations, at the Center for Functional Nanomaterials, which is a U.S. Department of Energy Office of Science User Facility, at Brookhaven National Laboratory under Contract No. DE-SC0012704. Partial low-magnification TEM imaging work was supported by S3IP/ADL, the State University of New York at Binghamton. \n\nAuthor Contributions. C.L., S.K., and X.C. contributed equally to this work. \n\nThe authors declare no competing financial interest.", "abstract": "This study demonstrates an atomic composition manipulation on Pt\u2013Ni nano-octahedra to enhance their electrocatalytic performance. By selectively extracting Ni atoms from the {111} facets of the Pt\u2013Ni nano-octahedra using gaseous carbon monoxide at an elevated temperature, a Pt-rich shell is formed, resulting in an \u223c2 atomic layer Pt-skin. The surface-engineered octahedral nanocatalyst exhibits a significant enhancement in both mass activity (\u223c1.8-fold) and specific activity (\u223c2.2-fold) toward the oxygen reduction reaction compared with its unmodified counterpart. After 20,000 potential cycles of durability tests, the surface-etched Pt\u2013Ni nano-octahedral sample shows a mass activity of 1.50 A/mg_(Pt), exceeding the initial mass activity of the unetched counterpart (1.40 A/mg_(Pt)) and outperforming the benchmark Pt/C (0.18 A/mg_(Pt)) by a factor of 8. DFT calculations predict this improvement with the Pt surface layers and support these experimental observations. This surface-engineering protocol provides a promising strategy for developing novel electrocatalysts with improved catalytic features.", "date": "2023-04-26", "date_type": "published", "publication": "Nano Letters", "volume": "23", "number": "8", "publisher": "American Chemical Society", "pagerange": "3476-3483", "id_number": "CaltechAUTHORS:20230502-761654700.4", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230502-761654700.4", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1808383" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "NSF", "grant_number": "CBET-2005250" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1905422" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012704" } ] }, "other_numbering_system": { "items": [ { "id": "1565", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.3c00567", "pub_year": "2023", "author_list": "Li, Can; Kwon, Soonho; et al." }, { "id": "https://authors.library.caltech.edu/records/tc5zd-6bm85", "eprint_status": "archive", "datestamp": "2025-12-11 16:45:58", "lastmod": "2025-12-11 16:47:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nanni-Ugo", "name": { "family": "Nanni", "given": "Ugo" }, "orcid": "0000-0001-6677-6117" }, { "name": { "family": "Scherler", "given": "Dirk" }, "orcid": "0000-0003-3911-2803" }, { "id": "Ayoub-Francois", "name": { "family": "Ayoub", "given": "Francois" }, "orcid": "0000-0002-7389-8400" }, { "name": { "family": "Millan", "given": "Romain" }, "orcid": "0000-0002-7987-1305" }, { "name": { "family": "Herman", "given": "Frederic" }, "orcid": "0000-0002-7237-4656" }, { "id": "Avouac-J-P", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" } ] }, "title": "Climatic control on seasonal variations in mountain glacier surface velocity", "ispublished": "pub", "full_text_status": "public", "note": "

© Author(s) 2023. This work is distributed under the Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union.

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Ugo Nanni thanks Bas Altena, Fanny Brun, Adrien Gilbert, Andreas Kääb and Lucas Malatesta for helpful comments and discussions. Ugo Nanni greatly thanks Jeremie Mouginot for helping with the processing and the discussions. The authors thank Astrid Lambrecht for providing meteorological data on the Fedchenko Glacier (Fig. S1). Dirk Scherler acknowledges funding from the European Research Council under the European Union's Horizon 2020 research and innovation program under grant agreement 759639.

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This research has been supported by the H2020 European Research Council (grant no. 759639) and the Resnick Sustainability Institute for Science, Energy and Sustainability, California Institute of Technology (grant no. 1).

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The glacier surface velocity maps as well as the along-flowline velocity profile data used for in the study are available at https://doi.org/10.5281/zenodo.7149214 (Nanni, 2022) under a Creative Commons Attribution 4.0 International license.

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V.1.0 of the codes which we developed to conduct our study (as detailed in Sect. 3) is preserved at https://doi.org/10.5281/zenodo.7149214 (Nanni, 2022) under a Creative Commons Attribution 4.0 International license. The codes are to be used in combination with ENVI's COSI-Corr add-on software, which is freely available at http://www.tectonics.caltech.edu/slip_history/spot_coseis/ (last access: 9 September 2022; Leprince et al., 2007). A Python version of COSI-Corr is currently under development and can be found here: https://github.com/SaifAati (Aati, 2023).

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Seasonal variations in glacier surface velocity over the western Pamirs is visualized here: https://doi.org/10.5446/61008 (Nanni, 2023).

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The supplement related to this article is available online at: https://doi.org/10.5194/tc-17-1567-2023-supplement.
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This paper was edited by Nicholas Barrand and reviewed by Peter Tuckett and one anonymous referee.

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", "abstract": "

Accurate measurements of ice flow are essential to predict future changes in glaciers and ice caps. Glacier displacement can in principle be measured on the large scale by cross-correlation of satellite images. At weekly to monthly scales, the expected displacement is often of the same order as the noise for the commonly used satellite images, complicating the retrieval of accurate glacier velocity. Assessments of velocity changes on short timescales and over complex areas such as mountain ranges are therefore still lacking but are essential to better understand how glacier dynamics are driven by internal and external factors. In this study, we take advantage of the wide availability and redundancy of satellite imagery over the western Pamirs to retrieve glacier velocity changes over 10 d intervals for 7 years and for a wide range of glacier geometry and dynamics. Our results reveal strong seasonal trends. In spring/summer, we observe velocity increases of up to 300 % compared to a slow winter period. These accelerations clearly migrate upglacier throughout the melt season, which we link to changes in subglacial hydrology efficiency. In autumn, we observe glacier accelerations that have rarely been observed before. These episodes are primarily confined to the upper ablation zone with a clear downglacier migration. We suggest that they result from glacier instabilities caused by sudden subglacial pressurization in response to (1) supraglacial pond drainage and/or (2) gradual closure of the hydrological system. Our 10 d resolved measurements allow us to characterize the short-term response of glaciers to changing meteorological and climatic conditions.

", "date": "2023-04-11", "date_type": "published", "publication": "The Cryosphere", "volume": "17", "number": "4", "publisher": "European Geosciences Union", "pagerange": "1567-1583", "issn": "1994-0424", "official_url": "https://authors.library.caltech.edu/records/tc5zd-6bm85", "funders": { "items": [ { "grant_number": "759639" }, { "grant_number": "1" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/tc-17-1567-2023", "primary_object": { "basename": "tc-17-1567-2023.pdf", "url": "https://authors.library.caltech.edu/records/tc5zd-6bm85/files/tc-17-1567-2023.pdf" }, "related_objects": [ { "basename": "tc-17-1567-2023-supplement.pdf", "url": "https://authors.library.caltech.edu/records/tc5zd-6bm85/files/tc-17-1567-2023-supplement.pdf" } ], "pub_year": "2023", "author_list": "Nanni, Ugo; Scherler, Dirk; et al." }, { "id": "https://authors.library.caltech.edu/records/9dcqe-8pd52", "eprint_id": 122076, "eprint_status": "archive", "datestamp": "2023-08-22 20:38:58", "lastmod": "2023-12-21 23:38:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Begu\u0161i\u0107-Tomislav", "name": { "family": "Begu\u0161i\u0107", "given": "Tomislav" }, "orcid": "0000-0002-7942-4134" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" } ] }, "title": "Two-dimensional infrared-Raman spectroscopy as a probe of water's tetrahedrality", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary", "note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nThe authors thank Haw-Wei Lin, Roman Korol, and Vignesh C. Bhethanabotla for helpful discussions. T.B. acknowledges financial support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship (grant number P2ELP2-199757). The authors gratefully acknowledge support from the National Science Foundation Chemical Structure, Dynamics and Mechanisms program (grant CHE-1665467). The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. \n\nContributions. T.B. conceived the study, implemented the theoretical models and methods, performed the simulations, and analyzed the data; T.B. and G.A.B. discussed the results and wrote the manuscript. \n\nData availability. The data generated in this study, together with the input files and scripts for plotting the data, have been deposited in the Zenodo database under accession code DOI:10.5281/zenodo.7619094.\n\nCode availability. Modified i-PI code90 used to run MD and TRPMD simulations is available at https://github.com/tbegusic/i-pi.git and https://doi.org/10.5281/zenodo.7682877; encorr code used for processing the outputs is available at https://github.com/tbegusic/encorr.git and https://doi.org/10.5281/zenodo.7682972. \n\nThe authors declare no competing interests.\n\n

Published - 41467_2023_Article_37667.pdf

Supplemental Material - 41467_2023_37667_MOESM1_ESM.pdf

", "abstract": "Two-dimensional spectroscopic techniques combining terahertz (THz), infrared (IR), and visible pulses offer a wealth of information about coupling among vibrational modes in molecular liquids, thus providing a promising probe of their local structure. However, the capabilities of these spectroscopies are still largely unexplored due to experimental limitations and inherently weak nonlinear signals. Here, through a combination of equilibrium-nonequilibrium molecular dynamics (MD) and a tailored spectrum decomposition scheme, we identify a relationship between the tetrahedral order of liquid water and its two-dimensional IR-IR-Raman (IIR) spectrum. The structure-spectrum relationship can explain the temperature dependence of the spectral features corresponding to the anharmonic coupling between low-frequency intermolecular and high-frequency intramolecular vibrational modes of water. In light of these results, we propose new experiments and discuss the implications for the study of tetrahedrality of liquid water.", "date": "2023-04-07", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "1950", "id_number": "CaltechAUTHORS:20230630-524992000.11", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230630-524992000.11", "funders": { "items": [ { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2ELP2-199757" }, { "agency": "NSF", "grant_number": "CHE-1665467" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-023-37667-7", "pmcid": "PMC10082090", "primary_object": { "basename": "41467_2023_Article_37667.pdf", "url": "https://authors.library.caltech.edu/records/9dcqe-8pd52/files/41467_2023_Article_37667.pdf" }, "related_objects": [ { "basename": "41467_2023_37667_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/9dcqe-8pd52/files/41467_2023_37667_MOESM1_ESM.pdf" } ], "pub_year": "2023", "author_list": "Begu\u0161i\u0107, Tomislav and Blake, Geoffrey A." }, { "id": "https://authors.library.caltech.edu/records/bpvgf-nza28", "eprint_id": 122467, "eprint_status": "archive", "datestamp": "2023-08-22 20:37:59", "lastmod": "2025-11-22 02:26:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" } ] }, "title": "Detecting and quantifying nanoparticle-mediated biomolecule delivery in plants", "ispublished": "pub", "full_text_status": "public", "keywords": "General Medicine; General Biochemistry, Genetics and Molecular Biology", "note": "\u00a9 2023 Springer Nature Limited. \n\nThe author thanks the Resnick Sustainability Institute at Caltech and the Henry Luce Foundation for funding. \n\nThe author declares no competing interests.", "abstract": "New nanomaterials are being developed for efficient biomolecule delivery to plants. However, detection and quantification of plant cell entry are challenging and currently rely on subjective methods that lack proper controls. The necessary considerations of performing nanoparticle-mediated delivery in plants and how to accurately quantify delivery efficiency are discussed.", "date": "2023-04-06", "date_type": "published", "publication": "Nature Reviews Methods Primers", "volume": "3", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 16", "id_number": "CaltechAUTHORS:20230725-857096000.39", "issn": "2662-8449", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-857096000.39", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Henry Luce Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s43586-023-00213-2", "pub_year": "2023", "author_list": "Demirer, Gozde S." }, { "id": "https://authors.library.caltech.edu/records/4rv52-71587", "eprint_id": 121347, "eprint_status": "archive", "datestamp": "2023-08-22 20:33:00", "lastmod": "2025-11-22 04:06:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ren-Bin-B", "name": { "family": "Ren", "given": "Bin B." }, "orcid": "0000-0003-1698-9696" }, { "id": "Rebollido-Isabel", "name": { "family": "Rebollido", "given": "Isabel" }, "orcid": "0000-0002-4388-6417" }, { "id": "Choquet-\u00c9lodie", "name": { "family": "Choquet", "given": "\u00c9lodie" }, "orcid": "0000-0002-9173-0740" }, { "id": "Zhou-Wen-Han", "name": { "family": "Zhou", "given": "Wen-Han" }, "orcid": "0000-0003-4229-8936" }, { "id": "Perrin-Marshall-D", "name": { "family": "Perrin", "given": "Marshall D." }, "orcid": "0000-0002-3191-8151" }, { "id": "Schneider-Glenn", "name": { "family": "Schneider", "given": "Glenn" }, "orcid": "0000-0002-4511-5966" }, { "id": "Milli-Julien", "name": { "family": "Milli", "given": "Julien" }, "orcid": "0000-0001-9325-2511" }, { "id": "Wolff-Schuyler-G", "name": { "family": "Wolff", "given": "Schuyler G." }, "orcid": "0000-0002-9977-8255" }, { "id": "Chen-Christine-H", "name": { "family": "Chen", "given": "Christine H." }, "orcid": "0000-0002-8382-0447" }, { "id": "Debes-John-H", "name": { "family": "Debes", "given": "John H." }, "orcid": "0000-0002-1783-8817" }, { "id": "Hagan-J-Brendan", "name": { "family": "Hagan", "given": "J. Brendan" } }, { "id": "Hines-Dean-C", "name": { "family": "Hines", "given": "Dean C." }, "orcid": "0000-0003-4653-6161" }, { "id": "Millar-Blanchaer-Maxwell-A", "name": { "family": "Millar-Blanchaer", "given": "Maxwell A." }, "orcid": "0000-0001-6205-9233" }, { "id": "Pueyo-Laurent", "name": { "family": "Pueyo", "given": "Laurent" }, "orcid": "0000-0003-3818-408X" }, { "id": "Roberge-Aki", "name": { "family": "Roberge", "given": "Aki" }, "orcid": "0000-0002-2989-3725" }, { "id": "Serabyn-Eugene", "name": { "family": "Serabyn", "given": "Eugene" } }, { "id": "Soummer-R\u00e9mi", "name": { "family": "Soummer", "given": "R\u00e9mi" }, "orcid": "0000-0003-2753-2819" } ] }, "title": "Debris disk color with the Hubble Space Telescope", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication. \n\nWe thank the anonymous referee for their comments that increased the clarity, depth, and width of this paper. We thank Xinyu Lu and Marco Delbo for helpful discussions. This work was funded by NASA through STScI Grant # HST-GO-15218.014-A for HST GO-15218 program (PI: \u00c9. Choquet). We are grateful for the productive discussions about dust scattering properties as part triggered by the EPOPEE (Etude des POussi\u00e8res Plan\u00e9taires Et Exoplan\u00e9taires) collaboration, supported by the French Planetology National Program (Programme National de Plan\u00e9tologie, PNP) of CNRS/INSU co-funded by CNES. We thank in particular Jean-Charles Augereau for helpful discussions about minimum grain sizes in debris disks and J\u00e9r\u00e9mie Lasue for inspiring discussions about the diversity and properties of Solar System dust. E.C. acknowledges funds from CNRS/PICS TACO-DESIRE program for supporting this research. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (PROTOPLANETS, grant agreement No. 101002188), and under the European Union's Horizon Europe research and innovation programme (ESCAPE, grant agreement No. 101044152). Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555. This research has made use of data reprocessed as part of the ALICE program, which was supported by NASA through grants HST-AR-12652 (PI: R. Soummer), HST-GO-11136 (PI: D. Golimowski), HST-GO-13855 (PI: \u00c9. Choquet), HST-GO-13331 (PI: L. Pueyo), and STScI Director's Discretionary Research funds, and was conducted at STScI which is operated by AURA under NASA contract NAS5-26555. This research has made use of the SIMBAD database (Wenger et al. 2000), operated at CDS, Strasbourg, France. This research has made use of the VizieR catalogue access tool, CDS, Strasbourg, France (DOI: 10.26093/cds/vizier). The original description of the VizieR service was published in A&AS 143, 23 (Ochsenbein et al. 2000). This research has made use of the SVO Filter Profile Service (http://svo2.cab.inta-csic.es/theory/fps/) supported from the Spanish MINECO through grant AYA2017-84089. The input images to ALICE processing are from the recalibrated NICMOS data products produced by the Legacy Archive project, \"A Legacy Archive PSF Library And Circumstellar Environments (LAPLACE) Investigation,\" (HST-AR-11279, PI: G. Schneider). This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. Part of the computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.\n\n

Published - aa45458-22.pdf

", "abstract": "Context. Multiwavelength scattered light imaging of debris disks may inform dust properties including typical size and mineral composition. Existing studies have investigated a small set of individual systems across a variety of imaging instruments and filters, calling for uniform comparison studies to systematically investigate dust properties. \n\nAims. We obtain the surface brightness of dust particles in debris disks by post-processing coronagraphic imaging observations, and compare the multiwavelength reflectance of dust. For a sample of resolved debris disks, we perform a systematic analysis on the reflectance properties of their birth rings. \n\nMethods. We reduced the visible and near-infrared images of 23 debris disk systems hosted by A through M stars using two coronagraphs on board the Hubble Space Telescope: the STIS instrument observations centered at 0.58 \u00b5m, and the NICMOS instrument at 1.12 \u00b5m or 1.60 \u00b5m. For proper recovery of debris disks, we used classical reference differential imaging for STIS, and adopted non-negative matrix factorization with forward modeling for NICMOS. By dividing disk signals by stellar signals to take into account intrinsic stellar color effects, we systematically obtained and compared the reflectance of debris birth rings at \u224890\u00ba scattering angle. \n\nResults. Debris birth rings typically exhibit a blue color at \u224890\u00ba scattering angle. As the stellar luminosity increases, the color tends to be more neutral. A likely L-shaped color\u2013albedo distribution indicates a clustering of scatterer properties. \n\nConclusions. The observed color trend correlates with the expected blow-out size of dust particles. The color-albedo clustering likely suggests different populations of dust in these systems. More detailed radiative transfer models with realistic dust morphology will contribute to explaining the observed color and color\u2013albedo distribution of debris systems.", "date": "2023-04", "date_type": "published", "publication": "Astronomy and Astrophysics", "volume": "672", "publisher": "EDP Sciences", "pagerange": "Art. No. A114", "id_number": "CaltechAUTHORS:20230509-880670200.3", "issn": "0004-6361", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230509-880670200.3", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "HST-GO-15218.014-A" }, { "agency": "Programme National de Plan\u00e9tologie (PNP)" }, { "agency": "Centre National de la Recherche Scientifique (CNRS)" }, { "agency": "Institut national des sciences de l'Univers (INSU)" }, { "agency": "Centre National d'\u00c9tudes Spatiales (CNES)" }, { "agency": "European Research Council (ERC)", "grant_number": "101002188" }, { "agency": "European Research Council (ERC)", "grant_number": "101044152" }, { "agency": "NASA", "grant_number": "NAS 5-26555" }, { "agency": "NASA", "grant_number": "HST-AR-12652" }, { "agency": "NASA", "grant_number": "HST-GO-11136" }, { "agency": "NASA", "grant_number": "HST-GO-13855" }, { "agency": "NASA", "grant_number": "HST-GO-13331" }, { "agency": "Space Telescope Science Institute" }, { "agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)", "grant_number": "AyA2017-84089" }, { "agency": "NASA", "grant_number": "HST-AR-11279" }, { "agency": "Gaia Multilateral Agreement" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1051/0004-6361/202245458", "primary_object": { "basename": "aa45458-22.pdf", "url": "https://authors.library.caltech.edu/records/4rv52-71587/files/aa45458-22.pdf" }, "pub_year": "2023", "author_list": "Ren, Bin B.; Rebollido, Isabel; et al." }, { "id": "https://authors.library.caltech.edu/records/ga8ac-53s46", "eprint_id": 121445, "eprint_status": "archive", "datestamp": "2023-08-22 20:26:21", "lastmod": "2023-12-22 21:33:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Debnath-Ramit", "name": { "family": "Debnath", "given": "Ramit" }, "orcid": "0000-0003-0727-5683" }, { "id": "Reiner-David-M", "name": { "family": "Reiner", "given": "David M." }, "orcid": "0000-0003-2004-8696" }, { "id": "Sovacool-Benjamin-K", "name": { "family": "Sovacool", "given": "Benjamin K." }, "orcid": "0000-0002-4794-9403" }, { "id": "M\u00fcller-Hansen-Finn", "name": { "family": "M\u00fcller-Hansen", "given": "Finn" }, "orcid": "0000-0002-0425-1996" }, { "id": "Repke-Tim", "name": { "family": "Repke", "given": "Tim" }, "orcid": "0000-0001-9661-6325" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. Michael" }, "orcid": "0000-0002-8113-4451" }, { "id": "Fitzgerald-Shaun-D", "name": { "family": "Fitzgerald", "given": "Shaun D." } } ] }, "title": "Conspiracy spillovers and geoengineering", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2023 The Author(s). Under a Creative Commons license - Attribution 4.0 International (CC BY 4.0) \n\nR.D. gratefully acknowledges support from the Bill and Melinda Gates Foundation [OPP1144], Cambridge Centre for Climate Repair, CambridgeZero, Laudes Foundation and Quadrature Climate Foundation, and the Google Cloud Climate Innovation Challenge Award. Caltech's Resnick Sustainability Institute supports R.M.A.'s work. We thank Twitter for granting access to their v2API. We also thank Google Jigsaw for granting access to their Perspective API via the Google Cloud Platform.\n\nBKS, FMH and TR acknowledge funding from the European Union's Horizon 2020 research and innovation programme under the European Research Council (ERC) Grant Agreement No. 951542-GENIE-ERC-2020-SyG, \"GeoEngineering and NegatIve Emissions pathways in Europe\" (GENIE). The content of this deliverable does not reflect the official opinion of the European Union. Responsibility for the information and views expressed herein lies entirely with the author(s). \n\nAuthor contribution. R.D. and S.D.F. conceived the study. R.D., S.D.F., and R.M.A. developed the analytical framework. R.D. developed the results, vizualisations and led the manuscript preparation. All authors interpreted the results, wrote and reviewed the manuscript. \n\nInclusion and diversity. One or more of the authors of this paper self-identifies as an underrepresented ethnic minority in their field of research or within their geographical location. One or more of the authors of this paper received support from a program designed to increase minority representation in their field of research. We avoided \"helicopter science\" practices by including the participating local contributors from the region where we conducted the research as authors on the paper. While citing references scientifically relevant for this work, we also actively worked to promote gender balance in our reference list. We support inclusive, diverse, and equitable conduct of research. \n\nData and code availability: \n\u2022 All data have been deposited at Mendeley Data and are publicly available as of publication. DOI is listed in the key resources table. Any additional information required to reanalyze the data reported in this paper is available from the lead contact upon request. \n\n\u2022 All codes have been deposited at GitHub and are publicly available as of the publication date. DOI is listed in the key resources table. Any additional information required to reanalyze the data reported in this paper is available from the lead contact upon request. \n\nThe authors declare no competing interests.\n\n

Published - main.pdf

Supplemental Material - 1-s2.0-S2589004223002432-mmc1.pdf

", "abstract": "Geoengineering techniques such as solar radiation management (SRM) could be part of a future technology portfolio to limit global temperature change. However, there is public opposition to research and deployment of SRM technologies. We use 814,924 English-language tweets containing #geoengineering globally over 13 years (2009\u20132021) to explore public emotions, perceptions, and attitudes toward SRM using natural language processing, deep learning, and network analysis. We find that specific conspiracy theories influence public reactions toward geoengineering, especially regarding \"chemtrails\" (whereby airplanes allegedly spray poison or modify weather through contrails). Furthermore, conspiracies tend to spillover, shaping regional debates in the UK, USA, India, and Sweden and connecting with broader political considerations. We also find that positive emotions rise on both the global and country scales following events related to SRM governance, and negative and neutral emotions increase following SRM projects and announcements of experiments. Finally, we also find that online toxicity shapes the breadth of spillover effects, further influencing anti-SRM views.", "date": "2023-03-17", "date_type": "published", "publication": "iScience", "volume": "26", "number": "3", "publisher": "Cell Press", "pagerange": "106166", "id_number": "CaltechAUTHORS:20230519-999570000.1", "issn": "2589-0042", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230519-999570000.1", "funders": { "items": [ { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1144" }, { "agency": "University of Cambridge" }, { "agency": "Laudes Foundation" }, { "agency": "Quadrature Climate Foundation" }, { "agency": "Google Cloud" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "European Research Council (ERC)", "grant_number": "951542" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.isci.2023.106166", "pmcid": "PMC10040962", "primary_object": { "basename": "main.pdf", "url": "https://authors.library.caltech.edu/records/ga8ac-53s46/files/main.pdf" }, "related_objects": [ { "basename": "1-s2.0-S2589004223002432-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/ga8ac-53s46/files/1-s2.0-S2589004223002432-mmc1.pdf" } ], "pub_year": "2023", "author_list": "Debnath, Ramit; Reiner, David M.; et al." }, { "id": "https://authors.library.caltech.edu/records/kr8jv-3m617", "eprint_id": 120644, "eprint_status": "archive", "datestamp": "2023-08-22 20:24:07", "lastmod": "2023-10-23 20:30:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dove-Lilian-A", "name": { "family": "Dove", "given": "Lilian A." }, "orcid": "0000-0001-8346-0034" }, { "id": "Viglione-Giuliana-A", "name": { "family": "Viglione", "given": "Giuliana A." }, "orcid": "0000-0002-6742-1120" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "id": "Flexas-M-Mar", "name": { "family": "Flexas", "given": "M. Mar" }, "orcid": "0000-0002-0617-3004" }, { "id": "Cason-Taylor-R", "name": { "family": "Cason", "given": "Taylor R." } }, { "id": "Sprintall-Janet", "name": { "family": "Sprintall", "given": "Janet" }, "orcid": "0000-0002-7428-7580" } ] }, "title": "Controls on Wintertime Ventilation in Southern Drake Passage", "ispublished": "pub", "full_text_status": "public", "keywords": "General Earth and Planetary Sciences; Geophysics", "note": "\u00a9 2023. The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nLAD was financially supported by the Resnick Sustainability Institute and an NSF graduate research fellowship. GAV and AFT were supported by NSF Award OPP-1246460. MMF was supported by the Internal Research and Technology Development program (Earth 2050 project) through the Jet Propulsion Laboratory, California Institute of Technology. TRC was supported by a Resnick Sustainability Institute WAVE summer research fellowship. JS was supported by NSF Awards OPP-1246160 and OCE-1755529. The authors would like to thank the Antarctic Support Contract staff as well as the captains and crews of the ARSV Laurence M. Gould for their support during the deployment and recovery cruises. LAD thanks Zachary K. Erickson for useful discussions while preparing this manuscript. The authors are grateful for the reviews of four reviewers, whose critiques improved the quality of this manuscript. \n\nData Availability Statement. Seaglider data are archived at the NOAA National Centers for Environmental Information (https://www.ncei.noaa.gov/archive/accession/0276223). Sea level anomaly and surface velocity products were produced and distributed by the Copernicus Marine 360 and Environment Monitoring Service (https://data.marine.copernicus.eu/product/SEALEVEL_GLO_PHY_L4_MY_008_047/description). Estimates of surface forcing fields (wind speed and direction, surface heat fluxes) for Drake Passage were obtained from the ERA5 atmospheric reanalysis from the European Centre for Medium-Range Weather Forecasts (https://cds.climate.copernicus.eu/cdsapp#!/dataset/10.24381/cds.bd0915c6). \n\nLilian A. Dove and Giuliana A. Viglione contributed equally to this work.\n\n

Published - Geophysical_Research_Letters_-_2023_-_Dove_-_Controls_on_Wintertime_Ventilation_in_Southern_Drake_Passage.pdf

Supplemental Material - 2022gl102550-sup-0001-supporting_information_si-s01.pdf

", "abstract": "Drake Passage is a key region for transport between the surface and interior ocean, but a mechanistic understanding of this exchange remains immature. Here, we present wintertime, submesoscale-resolving hydrographic transects spanning the southern boundary of the Antarctic Circumpolar Current and the Polar Front (PF). Despite the strong surface wind and buoyancy forcing, a freshwater lens suppresses surface-interior exchange south of the PF; ventilation is instead localized to the PF. Multiple lines of the analysis suggest submesoscale processes contribute to ventilation at the PF, including small-scale, O(10 km), frontal structure in water mass properties below the mixed layer and modulation of a surface eddy diffusivity at sub-50 km scales. These results show that ventilation is sensitive to both submesoscale properties near fronts and non-local processes, for example, sea-ice melt, that set stratification and mixed layer properties. This highlights the need for adaptive observing strategies to constrain Southern Ocean heat and carbon budgets.", "date": "2023-03-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "50", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2022GL102550", "id_number": "CaltechAUTHORS:20230330-579847500.5", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230330-579847500.5", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "NSF", "grant_number": "OPP-1246460" }, { "agency": "JPL Internal Research and Technology Development Program" }, { "agency": "NSF", "grant_number": "OPP-1246160" }, { "agency": "NSF", "grant_number": "OCE-1755529" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2022gl102550", "primary_object": { "basename": "2022gl102550-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/kr8jv-3m617/files/2022gl102550-sup-0001-supporting_information_si-s01.pdf" }, "related_objects": [ { "basename": "Geophysical_Research_Letters_-_2023_-_Dove_-_Controls_on_Wintertime_Ventilation_in_Southern_Drake_Passage.pdf", "url": "https://authors.library.caltech.edu/records/kr8jv-3m617/files/Geophysical_Research_Letters_-_2023_-_Dove_-_Controls_on_Wintertime_Ventilation_in_Southern_Drake_Passage.pdf" } ], "pub_year": "2023", "author_list": "Dove, Lilian A.; Viglione, Giuliana A.; et al." }, { "id": "https://authors.library.caltech.edu/records/93ew7-17s20", "eprint_id": 119875, "eprint_status": "archive", "datestamp": "2023-08-22 20:22:06", "lastmod": "2025-11-21 21:16:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nie-Weixuan", "name": { "family": "Nie", "given": "Weixuan" }, "orcid": "0000-0003-2094-6840" }, { "id": "Heim-Gavin-P", "name": { "family": "Heim", "given": "Gavin P." }, "orcid": "0000-0002-9244-6565" }, { "id": "Watkins-Nicholas-B", "name": { "family": "Watkins", "given": "Nicholas B." }, "orcid": "0000-0001-7251-9387" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Organic Additive-derived Films on Cu Electrodes Promote Electrochemical CO\u2082 Reduction to C\u2082\u208a Products Under Strongly Acidic Conditions", "ispublished": "pub", "full_text_status": "public", "keywords": "General Chemistry; Catalysis", "note": "\u00a9 2023 Wiley-VCH. \n\nThis material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. The Resnick Sustainability Institute at Caltech is also acknowledged for its support of enabling infrastructure and facilities. We thank Dr. Yueshen Wu for SEM measurement assistance. We thank Dr. Shaoyang Lin for GC-MS measurement assistance. \n\nData Availability Statement. The data that support the findings of this study are available in the Supporting Information of this article. \n\nThe authors declare no conflict of interest.", "abstract": "Electrochemical CO\u2082 reduction (CO\u2082R) at low pH is desired for high CO\u2082 utilization; the competing hydrogen evolution reaction (HER) remains a challenge. High alkali cation concentration at a high operating current density has recently been used to promote electrochemical CO\u2082R at low pH. Herein we report an alternative approach to selective CO\u2082R (>70\u2009% Faradaic efficiency for C\u2082\u208a products, FE_(C2+)) at low pH (pH\u20052; H\u2083PO\u2084/KH\u2082PO\u2084) and low potassium concentration ([K\u207a]=0.1\u2005M) using organic film-modified polycrystalline copper (Modified-Cu). Such an electrode effectively mitigates HER due to attenuated proton transport. Modified-Cu still achieves high FE_(C2+) (45\u2009% with Cu foil /55\u2009% with Cu GDE) under 1.0\u2005M H\u2083PO\u2084 (pH\u22481) at low [K\u207a] (0.1\u2005M), even at low operating current, conditions where HER can otherwise dominate.", "date": "2023-03-13", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "62", "number": "12", "publisher": "Wiley", "pagerange": "Art. No. e202216102", "id_number": "CaltechAUTHORS:20230307-207211000.41", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230307-207211000.41", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.202216102", "pub_year": "2023", "author_list": "Nie, Weixuan; Heim, Gavin P.; et al." }, { "id": "https://authors.library.caltech.edu/records/mwkzk-rad83", "eprint_id": 120683, "eprint_status": "archive", "datestamp": "2023-08-22 20:21:48", "lastmod": "2023-10-18 17:56:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stark-Christopher-C", "name": { "family": "Stark", "given": "Christopher C." } }, { "id": "Ren-Bin", "name": { "family": "Ren", "given": "Bin" }, "orcid": "0000-0003-1698-9696" }, { "id": "MacGregor-Meredith-A", "name": { "family": "MacGregor", "given": "Meredith A." }, "orcid": "0000-0001-7891-8143" }, { "id": "Howard-Ward-S", "name": { "family": "Howard", "given": "Ward S." }, "orcid": "0000-0002-0583-0949" }, { "id": "Hurt-Spencer-A", "name": { "family": "Hurt", "given": "Spencer A." }, "orcid": "0000-0002-6903-9080" }, { "id": "Weinberger-Alycia-J", "name": { "family": "Weinberger", "given": "Alycia J." }, "orcid": "0000-0001-6654-7859" }, { "id": "Schneider-Glenn", "name": { "family": "Schneider", "given": "Glenn" }, "orcid": "0000-0002-4511-5966" }, { "id": "Choquet-\u00c9lodie", "name": { "family": "Choquet", "given": "\u00c9lodie" }, "orcid": "0000-0002-9173-0740" } ] }, "title": "The Apparent Absence of Forward Scattering in the HD 53143 Debris Disk", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThe authors acknowledge Pierre Kervella for assistance in assessing the binarity of HD 53143. This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 526555. These observations are associated with program 16202. Part of the computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.\n\n

Published - Stark_2023_ApJ_945_131.pdf

", "abstract": "HD 53143 is a mature Sun-like star and host to a broad disk of dusty debris, including a cold outer ring of planetesimals near 90 au. Unlike most other inclined debris disks imaged at visible wavelengths, the cold disk around HD 53143 appears as disconnected \"arcs\" of material, with no forward-scattering side detected to date. We present new, deeper Hubble Space Telescope Imaging Spectrograph coronagraphic observations of the HD 53143 debris disk and show that the forward-scattering side of the disk remains undetected. By fitting our KLIP-reduced observations via forward modeling with an optically thin disk model, we show that fitting the visible wavelength images with an azimuthally symmetric disk with unconstrained orientation results in an unphysical edge-on orientation that is at odds with recent ALMA observations, while constraining the orientation to that observed by ALMA results in nearly isotropically scattering dust. We show that the HD 53143 host star exhibits significant stellar variations due to spot rotation and revisit age estimates for this system.", "date": "2023-03-10", "date_type": "published", "publication": "Astrophysical Journal", "volume": "945", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 131", "id_number": "CaltechAUTHORS:20230404-289763500.5", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230404-289763500.5", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS 5-26555" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gaia Multilateral Agreement" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/1538-4357/acbb64", "primary_object": { "basename": "Stark_2023_ApJ_945_131.pdf", "url": "https://authors.library.caltech.edu/records/mwkzk-rad83/files/Stark_2023_ApJ_945_131.pdf" }, "pub_year": "2023", "author_list": "Stark, Christopher C.; Ren, Bin; et al." }, { "id": "https://authors.library.caltech.edu/records/vpwp8-xwb35", "eprint_id": 120050, "eprint_status": "archive", "datestamp": "2023-08-22 20:20:03", "lastmod": "2025-11-22 02:27:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Hanzhe", "name": { "family": "Liu", "given": "Hanzhe" }, "orcid": "0000-0001-9001-725X" }, { "id": "Michelsen-Jonathan-M", "name": { "family": "Michelsen", "given": "Jonathan M." }, "orcid": "0000-0002-7420-5610" }, { "id": "Mendes-Jocelyn-L", "name": { "family": "Mendes", "given": "Jocelyn L." }, "orcid": "0000-0003-3850-0724" }, { "id": "Klein-Isabel-M", "name": { "family": "Klein", "given": "Isabel M." }, "orcid": "0000-0001-6134-6732" }, { "id": "Bauers-Sage-R", "name": { "family": "Bauers", "given": "Sage R." }, "orcid": "0000-0002-6505-5016" }, { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Zakutayev-Andriy", "name": { "family": "Zakutayev", "given": "Andriy" }, "orcid": "0000-0002-3054-5525" }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott K." }, "orcid": "0000-0003-3538-2259" } ] }, "title": "Measuring Photoexcited Electron and Hole Dynamics in ZnTe and Modeling Excited State Core-Valence Effects in Transient Extreme Ultraviolet Reflection Spectroscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "General Materials Science; Physical and Theoretical Chemistry", "note": "\u00a9 2023 American Chemical Society. \n\nThis material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub, under Grant DE-SC0021266. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. Ground state optical absorption and XPS data were collected at the Molecular Materials Research Center in the Beckman Institute of the California Institute of Technology. I.M.K. and J.L.M. acknowledge support by the National Science Foundation Graduate Research Fellowship Program under Grant 1745301. \n\nAuthor Contributions. H.L. and J.M.M. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - jz2c03894_si_001.pdf

", "abstract": "Transient extreme ultraviolet (XUV) spectroscopy is becoming a valuable tool for characterizing solar energy materials because it can separate photoexcited electron and hole dynamics with element specificity. Here, we use surface-sensitive femtosecond XUV reflection spectroscopy to separately measure photoexcited electron, hole, and band gap dynamics of ZnTe, a promising photocathode for CO\u2082 reduction. We develop an ab initio theoretical framework based on density functional theory and the Bethe\u2013Salpeter equation to robustly assign the complex transient XUV spectra to the material's electronic states. Applying this framework, we identify the relaxation pathways and quantify their time scales in photoexcited ZnTe, including subpicosecond hot electron and hole thermalization, surface carrier diffusion, ultrafast band gap renormalization, and evidence of acoustic phonon oscillations.", "date": "2023-03-02", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "14", "number": "8", "publisher": "American Chemical Society", "pagerange": "2106-2111", "id_number": "CaltechAUTHORS:20230314-846094500.85", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230314-846094500.85", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Chemistry-and-Chemical-Engineering" } ] }, "doi": "10.1021/acs.jpclett.2c03894", "primary_object": { "basename": "jz2c03894_si_001.pdf", "url": "https://authors.library.caltech.edu/records/vpwp8-xwb35/files/jz2c03894_si_001.pdf" }, "pub_year": "2023", "author_list": "Liu, Hanzhe; Michelsen, Jonathan M.; et al." }, { "id": "https://authors.library.caltech.edu/records/npwrx-d8m85", "eprint_id": 121273, "eprint_status": "archive", "datestamp": "2023-08-22 20:16:33", "lastmod": "2025-11-22 04:02:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yue", "name": { "family": "Chen", "given": "Yue" }, "orcid": "0000-0002-7594-7587" }, { "id": "Zhao-Changhong", "name": { "family": "Zhao", "given": "Changhong" }, "orcid": "0000-0003-0539-8591" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" }, "orcid": "0000-0002-5923-0199" } ] }, "title": "An Energy Sharing Mechanism Considering Network Constraints and Market Power Limitation", "ispublished": "pub", "full_text_status": "public", "keywords": "General Computer Science", "note": "\u00a9 2023 IEEE. \n\nThis work was supported by the Chinese University of Hong Kong (CUHK) Direct Grant for Research under Grant 4055169. The work of Changhong Zhao was supported by the Hong Kong Research Grants Council ECS Award under Grant 24210220. The work of Steven H. Low was supported in part by NSF through ECCS under Grant 1931662, and in part by the Caltech Resnick and S2I Funds.", "abstract": "As the number of prosumers with distributed energy resources (DERs) grows, the conventional centralized operation scheme may suffer from conflicting interests, privacy concerns, and incentive inadequacy. In this paper, we propose an energy sharing mechanism to address the above challenges. It takes into account network constraints and fairness among prosumers. In the proposed energy sharing market, all prosumers play a generalized Nash game. The market equilibrium is proved to have nice features in a large market or when it is a variational equilibrium. To deal with the possible market failure, inefficiency, or instability in general cases, we introduce a price regulation policy to avoid market power exploitation. The improved energy sharing mechanism with price regulation can guarantee the existence and uniqueness of a socially near-optimal market equilibrium. Some advantageous properties are proved, such as the prosumer's individual rationality, a sharing price structure similar to the locational marginal price, and the tendency towards social optimum with an increasing number of prosumers. For implementation, a practical bidding algorithm is developed with a convergence condition. Experimental results validate the theoretical outcomes and show the practicability of our model and method.", "date": "2023-03", "date_type": "published", "publication": "IEEE Transactions on Smart Grid", "volume": "14", "number": "2", "publisher": "IEEE", "pagerange": "1027-1041", "id_number": "CaltechAUTHORS:20230502-727238500.2", "issn": "1949-3053", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230502-727238500.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Chinese University of Hong Kong", "grant_number": "4055169" }, { "agency": "Research Grants Council of Hong Kong", "grant_number": "24210220" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Center for Sensing to Intelligence (S2I)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Caltech-Center-for-Sensing-to-Intelligence-(S2I)" } ] }, "doi": "10.1109/tsg.2022.3198721", "pub_year": "2023", "author_list": "Chen, Yue; Zhao, Changhong; et al." }, { "id": "https://authors.library.caltech.edu/records/7xav1-m4r83", "eprint_id": 120077, "eprint_status": "archive", "datestamp": "2023-08-22 20:13:04", "lastmod": "2025-11-22 03:09:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brink-Daniel-P", "name": { "family": "Brink", "given": "Daniel P." }, "orcid": "0000-0003-4041-0250" }, { "id": "Larsson-Elin-M", "name": { "family": "Larsson", "given": "Elin M." }, "orcid": "0000-0003-1341-5937" }, { "id": "Garc\u00eda-Hidalgo-Javier", "name": { "family": "Garc\u00eda-Hidalgo", "given": "Javier" }, "orcid": "0000-0002-1909-847X" }, { "id": "Helgad\u00f3ttir-Helga", "name": { "family": "Helgad\u00f3ttir", "given": "Helga" } }, { "id": "Gorwa-Grauslund-Marie-F", "name": { "family": "Gorwa-Grauslund", "given": "Marie F." }, "orcid": "0000-0002-4810-4082" } ] }, "title": "Draft Genome Assembly of Stutzerimonas sp. Strain S1 and Achromobacter spanius Strain S4, Two Syringol-Metabolizing Bacteria Isolated from Compost Soil", "ispublished": "pub", "full_text_status": "public", "keywords": "Genetics; Immunology and Microbiology (miscellaneous); Molecular Biology", "note": "\u00a9 2023 Brink et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license. \n\nThis work was financed by the Swedish Foundation for Strategic Research through the grant contract RBP14-0052. Elin Larsson also acknowledges funding from the Resnick Sustainability Institute, California Institute of Technology, Pasadena, CA, USA. The computations and data handling were enabled by resources provided by the Swedish National Infrastructure for Computing (SNIC) at UPPMAX partially funded by the Swedish Research Council through grant agreement no. 2018-05973. Computations were performed in projects SNIC 2020/15-218 and SNIC 2021/22-698. \n\nWe also thank Sysav South Scania Waste Company (Malm\u00f6, Sweden) for kindly providing the compost sample used for the isolation. \n\nD.P.B. and E.M.L. performed the bioinformatics analysis. J.G.-H. and H.H. isolated the strains. D.P.B. designed the bioinformatics workflow and wrote the manuscript. M.F.G.-G. conceived the study and revised the manuscript. All authors read and approved the final manuscript.\n\n

Published - mra.01150-22.pdf

", "abstract": "Two bacterial strains able to use syringol as a sole carbon source were isolated from compost. The isolates, named S1 and S4, were sequenced using the Illumina platform. The final assemblies contained 4.2 Mbp, 63% GC, and 3,912 genes for S1 and 6.2 Mbp, 64% GC, and 5,503 genes for S4.", "date": "2023-03", "date_type": "published", "publication": "Microbiology Resource Announcements", "volume": "12", "number": "3", "publisher": "American Society for Microbiology", "pagerange": "e0115022", "id_number": "CaltechAUTHORS:20230315-645491100.10", "issn": "2576-098X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230315-645491100.10", "funders": { "items": [ { "agency": "Swedish Foundation for Strategic Research", "grant_number": "RBP14-0052" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Swedish Research Council", "grant_number": "2018-05973" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1128/mra.01150-22", "pmcid": "PMC10019166", "primary_object": { "basename": "mra.01150-22.pdf", "url": "https://authors.library.caltech.edu/records/7xav1-m4r83/files/mra.01150-22.pdf" }, "pub_year": "2023", "author_list": "Brink, Daniel P.; Larsson, Elin M.; et al." }, { "id": "https://authors.library.caltech.edu/records/64j4e-7fx68", "eprint_id": 120379, "eprint_status": "archive", "datestamp": "2023-08-22 20:14:39", "lastmod": "2023-12-22 22:28:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laskowski-Forrest-A-L", "name": { "family": "Laskowski", "given": "Forrest A. L." }, "orcid": "0000-0001-8909-483X" }, { "id": "McHaffie-Daniel-B", "name": { "family": "McHaffie", "given": "Daniel B." } }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Identification of potential solid-state Li-ion conductors with semi-supervised learning", "ispublished": "pub", "full_text_status": "public", "keywords": "Pollution; Nuclear Energy and Engineering; Renewable Energy, Sustainability and the Environment; Environmental Chemistry", "note": "

\u00a9 The Royal Society of Chemistry 2023.

F. A. L. L. acknowledges the support of the Arnold and Mabel Beckman Foundation via a 2020 Arnold O. Beckman Postdoctoral Fellowship in Chemical Sciences. F. A. L. L. would also like to thank Andrew J. Martinolich for his guidance and insightful scientific input. The NEB computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. K. A. S. acknowledges support from the David and Lucile Packard Foundation. Data availability. The data that support the findings of this study are available from the corresponding author upon reasonable request. There are no conflicts to declare.

\n\n

Supplemental Material - d2ee03499a1.pdf

", "abstract": "Despite ongoing efforts to identify high-performance electrolytes for solid-state Li-ion batteries, thousands of prospective Li-containing structures remain unexplored. Here, we employ a semi-supervised learning approach to expedite identification of ionic conductors. We screen 180 unique descriptor representations and use agglomerative clustering to cluster ~26,000 Li-containing structures. The clusters are then labeled with experimental ionic conductivity data to assess the fitness of the descriptors. By inspecting clusters containing the highest conductivity labels, we identify 212 promising structures that are further screened using bond valence site energy and nudged elastic band calculations. Li\u2083BS\u2083 is identified as a potential high-conductivity material and selected for experimental characterization. With sufficient defect engineering, we show that Li\u2083BS\u2083 is a superionic conductor with room temperature ionic conductivity greater than 1 mS cm\u207b\u00b9. While the semi-supervised method shows promise for identification of superionic conductors, the results illustrate a continued need for descriptors that explicitly encode for defects.", "date": "2023-03", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "16", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "1264-1276", "id_number": "CaltechAUTHORS:20230324-864130000.2", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230324-864130000.2", "funders": { "items": [ { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "David and Lucile Packard Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d2ee03499a", "primary_object": { "basename": "d2ee03499a1.pdf", "url": "https://authors.library.caltech.edu/records/64j4e-7fx68/files/d2ee03499a1.pdf" }, "pub_year": "2023", "author_list": "Laskowski, Forrest A. L.; McHaffie, Daniel B.; et al." }, { "id": "https://authors.library.caltech.edu/records/29sg0-zyg12", "eprint_id": 120283, "eprint_status": "archive", "datestamp": "2023-08-22 20:14:16", "lastmod": "2025-11-21 21:57:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mehta-Raaj-S", "name": { "family": "Mehta", "given": "Raaj S." } }, { "id": "Mayers-Jared-R", "name": { "family": "Mayers", "given": "Jared R." }, "orcid": "0000-0002-8607-1787" }, { "id": "Zhang-Yancong", "name": { "family": "Zhang", "given": "Yancong" }, "orcid": "0000-0002-2768-2975" }, { "id": "Bhosle-Amrisha", "name": { "family": "Bhosle", "given": "Amrisha" }, "orcid": "0000-0001-8669-4979" }, { "id": "Glasser-Nathaniel-R", "name": { "family": "Glasser", "given": "Nathaniel R." }, "orcid": "0000-0002-2833-5166" }, { "id": "Nguyen-Long-H", "name": { "family": "Nguyen", "given": "Long H." }, "orcid": "0000-0002-5436-4219" }, { "id": "Ma-Wenjie", "name": { "family": "Ma", "given": "Wenjie" } }, { "id": "Bae-Sena", "name": { "family": "Bae", "given": "Sena" }, "orcid": "0000-0002-7344-6922" }, { "id": "Branck-Tobyn", "name": { "family": "Branck", "given": "Tobyn" }, "orcid": "0000-0001-8634-3896" }, { "id": "Song-Kijun", "name": { "family": "Song", "given": "Kijun" }, "orcid": "0000-0002-6037-9345" }, { "id": "Sebastian-Luke", "name": { "family": "Sebastian", "given": "Luke" }, "orcid": "0000-0002-6863-9420" }, { "id": "Avila-Julian", "name": { "family": "Avila Pacheco", "given": "Julian" }, "orcid": "0000-0001-9388-3946" }, { "id": "Seo-Hyuk-Soo", "name": { "family": "Seo", "given": "Hyuk-Soo" }, "orcid": "0000-0003-0646-2102" }, { "id": "Clish-Clary", "name": { "family": "Clish", "given": "Clary" }, "orcid": "0000-0001-8259-9245" }, { "id": "Dhe-Paganon-Sirano", "name": { "family": "Dhe-Paganon", "given": "Sirano" }, "orcid": "0000-0003-0824-5929" }, { "id": "Ananthakrishnan-Ashwin-N", "name": { "family": "Ananthakrishnan", "given": "Ashwin N." }, "orcid": "0000-0002-9436-1821" }, { "id": "Franzosa-Eric-A", "name": { "family": "Franzosa", "given": "Eric A." }, "orcid": "0000-0002-8798-7068" }, { "id": "Balskus-Emily-P", "name": { "family": "Balskus", "given": "Emily P." }, "orcid": "0000-0001-5985-5714" }, { "id": "Chan-Andrew-T", "name": { "family": "Chan", "given": "Andrew T." } }, { "id": "Huttenhower-Curtis", "name": { "family": "Huttenhower", "given": "Curtis" }, "orcid": "0000-0002-1110-0096" } ] }, "title": "Gut microbial metabolism of 5-ASA diminishes its clinical efficacy in inflammatory bowel disease", "ispublished": "pub", "full_text_status": "public", "keywords": "General Biochemistry, Genetics and Molecular Biology; General Medicine", "note": "\u00a9 2023 Springer Nature. \n\nWe express our sincere thanks to the members of the Huttenhower laboratory for their editorial assistance. The computations in this paper were run on the FASRC Cannon cluster supported by the FAS Division of Science Research Computing Group at Harvard University or on the O2 High Performance Compute Cluster, supported by the Research Computing Group, at Harvard Medical School. See https://it.hms.harvard.edu/our-services/research-computing for more information. Funding: National Institutes of Health grant R35 CA253185 (A.T.C.); National Institutes of Health grant R24 DK110499-01A1 (C.H.); National Institutes of Health grant T32HL008633-36 (J.R.M.); National Institutes of Health grant 1K23DK125838 (L.H.N.); American College of Gastroenterology (R.S.M.); Crohn's & Colitis Foundation (R.S.M. and L.H.N.); American Gastroenterological Association (L.H.N. and W.M.); Pfizer Ulcerative Colitis Grant (A.T.C.); Stuart and Suzanne Steele MGH Research Scholarship (A.T.C.); Howard Hughes Medical Institute (E.P.B.); National Science Foundation Postdoctoral Research Fellowship in Biology grant 1907240 (N.R.G.); National Science Foundation Alan T. Waterman Award 2038059 (J.R.M.); Linde Family Foundation (S.D.P.); Novartis Institute for Biomedical Research (S.D.P.); Doris Duke Charitable Foundation (S.D.P.); National Institutes of Health grant P30 GM124165 (S.D.P.); and National Institutes of Health-ORIP HEI grant S10OD021527 (S.D.P.). \n\nContributions. Conceptualization: R.S.M., E.P.B., A.T.C. and C.H. Methodology: R.S.M., J.R.M., Y.Z., N.G., J.A.P., H.S., C.C., S.D.P., E.F., E.P.B. and C.H. Investigation: R.S.M., J.R.M., Y.Z., A.B., N.R.G., L.H.N., W.M., S.B., T.B., K.S., L.B., A.N.A. and E.F. Visualization: R.S.M. and J.R.M. Funding acquisition: R.S.M., E.P.B., A.T.C. and C.H. Project administration: R.S.M., E.P.B., A.T.C. and C.H. Supervision: E.P.B., A.T.C. and C.H. contributed equally. Writing\u2014original draft: R.S.M., J.R.M., A.T.C. and C.H. Writing\u2014review and editing: R.S.M., J.R.M., Y.Z., N.R.G., A.B., L.H.N., W.M., S.B., T.B., A.N.A., J.A.P., H.S., S.D.P., E.F., E.P.B., A.T.C. and C.H. \n\nThese authors contributed equally: Raaj S. Mehta, Jared R. Mayers. \n\nData availability. All multi-omics and participant data from the HMP2 used in this analysis are available at http://IBDMDB.org. Access to PRISM data may be available after contact of rxavier@molbio.harvard.edu. The SPARC IBD data are available upon approved application to Crohn's & Colitis Foundation IBD Plexus (https://www.crohnscolitisfoundation.org/ibd-plexus). \n\nCode availability. All analysis code can be accessed at https://github.com/drraajmehta/hmp2_5asa for purposes of reproducibility. \n\nCompeting interests. C.H. is a consultant to Zoe, Ltd. and is on the scientific advisory boards of Seres Therapeutics and Empress Therapeutics. A.T.C. has been an investigator on a clinical study supported by Zoe, Ltd. Other authors declare that they have no competing interests. R.S.M., J.R.M., E.P.B., A.T.C. and C.H. filed a provisional patent application (63/383,269) on 11 November 2022.\n\n

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", "abstract": "For decades, variability in clinical efficacy of the widely used inflammatory bowel disease (IBD) drug 5-aminosalicylic acid (5-ASA) has been attributed, in part, to its acetylation and inactivation by gut microbes. Identification of the responsible microbes and enzyme(s), however, has proved elusive. To uncover the source of this metabolism, we developed a multi-omics workflow combining gut microbiome metagenomics, metatranscriptomics and metabolomics from the longitudinal IBDMDB cohort of 132 controls and patients with IBD. This associated 12 previously uncharacterized microbial acetyltransferases with 5-ASA inactivation, belonging to two protein superfamilies: thiolases and acyl-CoA N-acyltransferases. In vitro characterization of representatives from both families confirmed the ability of these enzymes to acetylate 5-ASA. A cross-sectional analysis within the discovery cohort and subsequent prospective validation within the independent SPARC IBD cohort (n\u2009=\u2009208) found three of these microbial thiolases and one acyl-CoA N-acyltransferase to be epidemiologically associated with an increased risk of treatment failure among 5-ASA users. Together, these data address a longstanding challenge in IBD management, outline a method for the discovery of previously uncharacterized gut microbial activities and advance the possibility of microbiome-based personalized medicine.", "date": "2023-03", "date_type": "published", "publication": "Nature Medicine", "volume": "29", "number": "3", "publisher": "Nature Publishing Group", "pagerange": "700-709", "id_number": "CaltechAUTHORS:20230321-823036300.93", "issn": "1078-8956", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230321-823036300.93", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R35 CA253185" }, { "agency": "NIH", "grant_number": "R24 DK110499-01A1" }, { "agency": "NIH Predoctoral Fellowship", "grant_number": "T32HL008633-36" }, { "agency": "NIH", "grant_number": "1K23DK125838" }, { "agency": "American College of Gastroenterology" }, { "agency": "Crohn's and Colitis Foundation of America" }, { "agency": "American Gastroenterological Association" }, { "agency": "Pfizer" }, { "agency": "Massachusetts General Hospital" }, { "agency": "Howard Hughes Medical Institute (HHMI)" }, { "agency": "NSF Biology Postdoctoral Fellowship", "grant_number": "DBI-1907240" }, { "agency": "NSF", "grant_number": "CHE-2038059" }, { "agency": "Linde Family Foundation" }, { "agency": "Novartis Institute for Biomedical Research" }, { "agency": "Doris Duke Charitable Foundation" }, { "agency": "NIH", "grant_number": "P30 GM124165" }, { "agency": "NIH", "grant_number": "S10OD021527" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41591-023-02217-7", "primary_object": { "basename": "41591_2023_2217_Fig15_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig15_ESM.jpg" }, "related_objects": [ { "basename": "41591_2023_2217_Fig6_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig6_ESM.jpg" }, { "basename": "41591_2023_2217_Fig7_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig7_ESM.jpg" }, { "basename": "41591_2023_2217_Fig9_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig9_ESM.jpg" }, { "basename": "41591_2023_2217_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_MOESM1_ESM.pdf" }, { "basename": "41591_2023_2217_Fig11_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig11_ESM.jpg" }, { "basename": "41591_2023_2217_Fig12_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig12_ESM.jpg" }, { "basename": "41591_2023_2217_Fig13_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig13_ESM.jpg" }, { "basename": "41591_2023_2217_Fig14_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig14_ESM.jpg" }, { "basename": "41591_2023_2217_Fig8_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig8_ESM.jpg" }, { "basename": "41591_2023_2217_MOESM3_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_MOESM3_ESM.xlsx" }, { "basename": "41591_2023_2217_Fig10_ESM.jpg", "url": "https://authors.library.caltech.edu/records/29sg0-zyg12/files/41591_2023_2217_Fig10_ESM.jpg" } ], "pub_year": "2023", "author_list": "Mehta, Raaj S.; Mayers, Jared R.; et al." }, { "id": "https://authors.library.caltech.edu/records/qnm5d-5sg35", "eprint_id": 120584, "eprint_status": "archive", "datestamp": "2023-08-22 20:15:10", "lastmod": "2025-11-22 02:23:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Legendre-Mark", "name": { "family": "Legendre", "given": "Mark" } }, { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" } ] }, "title": "Improving crop genetic transformation to feed the world", "ispublished": "pub", "full_text_status": "public", "keywords": "Bioengineering; Biotechnology", "note": "\u00a9 2022 Elsevier. \n\nWe acknowledge funding from the Resnick Sustainability Institute and Caltech startup funds. \n\nDeclaration of interests. No interests are declared.", "abstract": "Food security is threatened by rising global population and effects of climate change. Most of our calories come from a few crops that are difficult to improve. Lowe et al. developed a plant transformation approach enabling crop genetic engineering that could provide a route to a future with greater food security.", "date": "2023-03", "date_type": "published", "publication": "Trends in Biotechnology", "volume": "41", "number": "3", "publisher": "Cell Press", "pagerange": "264-266", "id_number": "CaltechAUTHORS:20230328-709109200.73", "issn": "0167-7799", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230328-709109200.73", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.tibtech.2022.12.002", "pub_year": "2023", "author_list": "Legendre, Mark and Demirer, Gozde S." }, { "id": "https://authors.library.caltech.edu/records/5hmd0-kwa42", "eprint_id": 121081, "eprint_status": "archive", "datestamp": "2023-08-22 20:16:06", "lastmod": "2025-11-21 23:52:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schiffer-Zachary-J", "name": { "family": "Schiffer", "given": "Zachary J." }, "orcid": "0000-0001-6069-8613" }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott K." }, "orcid": "0000-0003-3538-2259" } ] }, "title": "Reports From The Frontier-Heterogeneous Electrocatalysts for Sustainable Electrochemical Synthesis", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Electrochemistry", "note": "\u00a9 2023 by The Electrochemical Society.\n\nThe author is funded by the Liquid Sunlight Alliance, which is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266 and the US Department of Energy, Advanced Research Projects Agency\u2013Energy (ARPA-e) under contract number DE-AR0001407. The author would also like to acknowledge The Resnick Sustainability Institute at Caltech. Additionally, the author would like to thank Nicholas Watkins and Karthish Manthiram for discussions and feedback on this work.", "abstract": "One key strategy toward decarbonizing chemical synthesis is to reduce reliance on fossil fuels as an energy source. The increased availability of renewable electricity from sources such as solar and wind offers opportunities to both reduce reliance on fossil fuels and electrify chemical manufacturing. While there are many possible uses for renewable electricity, such as joule heating of reactors, one approach is to use these electrons to make and break chemical bonds directly via electrochemistry.", "date": "2023-03", "date_type": "published", "publication": "Interface", "volume": "32", "number": "1", "publisher": "Electrochemical Society", "pagerange": "37-39", "id_number": "CaltechAUTHORS:20230420-614686900.9", "issn": "1064-8208", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230420-614686900.9", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AR0001407" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1149/2.f05231if", "pub_year": "2023", "author_list": "Schiffer, Zachary J. and Cushing, Scott K." }, { "id": "https://authors.library.caltech.edu/records/99twq-8jn27", "eprint_id": 121267, "eprint_status": "archive", "datestamp": "2023-08-22 20:16:30", "lastmod": "2023-10-23 20:30:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yuan-Ye", "name": { "family": "Yuan", "given": "Ye" }, "orcid": "0000-0001-7858-0437" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Ardakanian-Omid", "name": { "family": "Ardakanian", "given": "Omid" }, "orcid": "0000-0002-6711-5502" }, { "id": "Tomlin-Claire-J", "name": { "family": "Tomlin", "given": "Claire J." }, "orcid": "0000-0003-3192-3185" } ] }, "title": "Inverse Power Flow Problem", "ispublished": "pub", "full_text_status": "public", "keywords": "Control and Optimization; Computer Networks and Communications; Signal Processing; Control and Systems Engineering", "note": "\u00a9 2023 IEEE. \n\nThe work of Ye Yuan was supported by the National Natural Science Foundation of China under Grant 92167201. \n\nThe authors would like to thank Dr. W. Zhou (Huazhong University of Science and Technology) for useful discussion. The authors would also like to thank the support of the US NSF through grants ECCS 1931662, 932611, Caltech Resnick Institure, and the National Sciences and Engineering Research Council of Canada through grant RGPIN-2019-04349.", "abstract": "We formulate an inverse power flow problem that infers a nodal admittance matrix from voltage and current phasors measured at a number of buses. We show that the admittance matrix can be uniquely identified from a sequence of measurements corresponding to different steady states when every node in the system is equipped with a measurement device, and a Kron-reduced admittance matrix can be determined even if some nodes in the system are not monitored (hidden nodes). We propose an effective algorithm to uncover the actual admittance matrix of a radial system with hidden nodes from its Kron-reduced admittance matrix.", "date": "2023-03", "date_type": "published", "publication": "IEEE Transactions on Control of Network Systems", "volume": "10", "number": "1", "publisher": "IEEE", "pagerange": "261-273", "id_number": "CaltechAUTHORS:20230502-984953000.1", "issn": "2325-5870", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230502-984953000.1", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "92167201" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "NSF", "grant_number": "ECCS-932611" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)", "grant_number": "RGPIN-2019-04349" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/tcns.2022.3199084", "pub_year": "2023", "author_list": "Yuan, Ye; Low, Steven H.; et al." }, { "id": "https://authors.library.caltech.edu/records/dhhy4-y6k16", "eprint_id": 122084, "eprint_status": "archive", "datestamp": "2023-08-22 19:06:16", "lastmod": "2025-11-22 02:26:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Warmack-Rebeccah-A", "name": { "family": "Warmack", "given": "Rebeccah A." }, "orcid": "0000-0002-9612-0511" }, { "id": "Maggiolo-Ailiena-O", "name": { "family": "Maggiolo", "given": "Ailiena O." }, "orcid": "0000-0003-1707-5060" }, { "id": "Orta-Andres", "name": { "family": "Orta", "given": "Andres" }, "orcid": "0000-0003-0673-1413" }, { "id": "Wenke-Belinda-B", "name": { "family": "Wenke", "given": "Belinda B." }, "orcid": "0000-0003-3214-6197" }, { "id": "Howard-James-B", "name": { "family": "Howard", "given": "James B." } }, { "id": "Rees-D-C", "name": { "family": "Rees", "given": "Douglas C." }, "orcid": "0000-0003-4073-1185" } ] }, "title": "Structural consequences of turnover-induced homocitrate loss in nitrogenase", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary", "note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nThis work was funded by support from the Howard Hughes Medical Institute (D.C.R.), NIH grant GM045162 (D.C.R.), and NIH GM143836-01 (R.A.W.). The foundational contributions of Dr. Thomas Spatzal to establishing the anaerobic Vitrobot system are gratefully acknowledged. We thank Dr. Jens Kaiser, Dr. Songye Chen, Dr. Trixia Buscagan, and Przemyslaw Dutka for their invaluable discussions. IC-MS and ICP-MS were performed on instrumentation made available by the Resnick Sustainability Institute's Water and Environment Lab at the California Institute of Technology. EPR data were collected at the Caltech EPR Facility which is supported by NSF-1531940. Bottom-up mass spectrometry of protein samples was performed at the Beckman Proteome Exploration Laboratory supported by the Arnold and Mabel Beckman Foundation. We thank Dr. Nathan Dalleska, Dr. Paul Oyala, and Dr. Ting-Yu Wang for their support and assistance with these analyses. The generous support of the Beckman Institute for the Caltech CryoEM Resource Center was essential for the performance of this research. We dedicate this work to our co-author Dr. James B. Howard who passed during the course of this work. \n\nContributions. R.A.W. and D.C.R. designed experiments. R.A.W. performed sample preparation, biochemical analyses, electron microscopy data collection and analyses, model building, and refinement. A.O.M. performed cryoEM model building and refinement. A.O. purified protein from the mutant A. vinelandii. B.B.W. performed initial tests of anaerobic cryoEM workflow. J.B.H. provided valuable advice on the project and the manuscript. D.C.R. supervised all research. R.A.W. and D.C.R. wrote the manuscript and all authors contributed to revisions. \n\nData availability. The single particle cryoEM maps and models generated in this study have been deposited into the PDB and EMDB for release upon publication. Reconstructed maps and refined models have been deposited with the following PDB and EMDB codes: 8CRS, EMD-26957 (MoFe^(As-isolated)); PDB 8DBX, EMD-27316 (MoFe^(Oxidized)); PDB 8ENL, EMD-28272 (MoFe^(Alkaline-inactivated)); PDB 8ENM, EMD-28273 (MoFe^(Alkaline)); PDB 8ENN, EMD-28274 (MoFe^(\u0394NifV)); PDB 8ENO, EMD-28275 (MoFe^(\u0394NifV)-NafT). The Uniprot all-reviewed A. vinelandii database was used for the analysis of mass spectrometry data. All other data are available from the corresponding authors upon reasonable request. Source data are provided with this paper. \n\nThe authors declare no competing interests.\n\n

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", "abstract": "Nitrogenase catalyzes the ATP-dependent reduction of dinitrogen to ammonia during the process of biological nitrogen fixation that is essential for sustaining life. The active site FeMo-cofactor contains a [7Fe:1Mo:9S:1C] metallocluster coordinated with an R-homocitrate (HCA) molecule. Here, we establish through single particle cryoEM and chemical analysis of two forms of the Azotobacter vinelandii MoFe-protein \u2013 a high pH turnover inactivated species and a \u2206NifV variant that cannot synthesize HCA \u2013 that loss of HCA is coupled to \u03b1-subunit domain and FeMo-cofactor disordering, and formation of a histidine coordination site. We further find a population of the \u2206NifV variant complexed to an endogenous protein identified through structural and proteomic approaches as the uncharacterized protein NafT. Recognition by endogenous NafT demonstrates the physiological relevance of the HCA-compromised form, perhaps for cofactor insertion or repair. Our results point towards a dynamic active site in which HCA plays a role in enabling nitrogenase catalysis by facilitating activation of the FeMo-cofactor from a relatively stable form to a state capable of reducing dinitrogen under ambient conditions.", "date": "2023-02-25", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 1091", "id_number": "CaltechAUTHORS:20230630-537337000.8", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230630-537337000.8", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Howard Hughes Medical Institute (HHMI)" }, { "agency": "NIH", "grant_number": "GM045162" }, { "agency": "NIH", "grant_number": "GM143836-01" }, { "agency": "NSF", "grant_number": "CHE-1531940" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-023-36636-4", "pmcid": "PMC9968304", "primary_object": { "basename": "41467_2023_36636_MOESM8_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_36636_MOESM8_ESM.xlsx" }, "related_objects": [ { "basename": "41467_2023_Article_36636.pdf", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_Article_36636.pdf" }, { "basename": "41467_2023_36636_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_36636_MOESM1_ESM.pdf" }, { "basename": "41467_2023_36636_MOESM3_ESM.pdf", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_36636_MOESM3_ESM.pdf" }, { "basename": "41467_2023_36636_MOESM4_ESM.xls", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_36636_MOESM4_ESM.xls" }, { "basename": "41467_2023_36636_MOESM5_ESM.mov", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_36636_MOESM5_ESM.mov" }, { "basename": "41467_2023_36636_MOESM6_ESM.mp4", "url": "https://authors.library.caltech.edu/records/dhhy4-y6k16/files/41467_2023_36636_MOESM6_ESM.mp4" } ], "pub_year": "2023", "author_list": "Warmack, Rebeccah A.; Maggiolo, Ailiena O.; et al." }, { "id": "https://authors.library.caltech.edu/records/tgaw7-95v03", "eprint_id": 119280, "eprint_status": "archive", "datestamp": "2024-02-20 23:04:42", "lastmod": "2024-02-20 23:04:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Garrido\u2010Barros-Pablo", "name": { "family": "Garrido\u2010Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Light Alters the NH\u2083 vs N\u2082H\u2084 Product Profile in Iron-catalyzed Nitrogen Reduction via Dual Reactivity from an Iron Hydrazido (Fe=NNH\u2082) Intermediate", "ispublished": "pub", "full_text_status": "public", "keywords": "General Chemistry; Catalysis", "note": "We thank the National Institutes of Health (R01GM-075757) for support of this work; the Dow Next Generation Educator Funds and Instrumentation Grants for their support of the NMR facility at Caltech; the Resnick Water and Environment Laboratory at Caltech for the use of instrumentation. P.G.B. thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship. M.J.C. thanks the Resnick Sustainability Institute for a graduate fellowship. \n\nThe authors declare no conflict of interest. \n\nData Availability Statement. The data that support the findings of this study are available in the Supporting Information of this article.\n\n

Supplemental Material - anie202216693-sup-0001-misc_information.pdf

", "abstract": "Whereas synthetically catalyzed nitrogen reduction (N\u2082R) to produce ammonia is widely studied, catalysis to instead produce hydrazine (N\u2082H\u2084) has received less attention despite its considerable mechanistic interest. Herein, we disclose that irradiation of a tris(phosphine)borane (P\u2083\u1d2e) Fe catalyst, P\u2083\u1d2eFe\u207a, significantly alters its product profile to increase N\u2082H\u2084 versus NH\u2083; P\u2083\u1d2eFe\u207a is otherwise known to be highly selective for NH\u2083. We posit a key terminal hydrazido intermediate, P\u2083\u1d2eFe=NNH\u2082, as selectivity-determining. Whereas its singlet ground state undergoes protonation to liberate NH\u2083, a low-lying triplet excited state leads to reactivity at N_\u03b1 and formation of N\u2082H\u2084. Associated electrochemical and spectroscopic studies establish that N\u2082H\u2084 lies along a unique product pathway; NH3 is not produced from N\u2082H\u2084. Our findings are distinct from the canonical mechanism for hydrazine formation, which proceeds via a diazene (HN=NH) intermediate and showcase light as a tool to tailor selectivity.", "date": "2023-02-20", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "62", "number": "9", "publisher": "Wiley", "pagerange": "e202216693", "id_number": "CaltechAUTHORS:20230214-87246900.10", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230214-87246900.10", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM070757" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Ram\u00f3n Areces Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.202216693", "pmcid": "PMC9998131", "primary_object": { "basename": "anie202216693-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/tgaw7-95v03/files/anie202216693-sup-0001-misc_information.pdf" }, "related_objects": [ { "basename": "nihms-1862564.pdf", "url": "https://authors.library.caltech.edu/records/tgaw7-95v03/files/nihms-1862564.pdf" } ], "pub_year": "2023", "author_list": "Garrido\u2010Barros, Pablo; Chalkley, Matthew J.; et al." }, { "id": "https://authors.library.caltech.edu/records/a1mkq-n6960", "eprint_id": 120241, "eprint_status": "archive", "datestamp": "2023-08-22 19:02:58", "lastmod": "2025-11-21 22:08:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rich-Jeffrey-A", "name": { "family": "Rich", "given": "J." }, "orcid": "0000-0002-5807-5078" }, { "id": "Aalto-Susanne", "name": { "family": "Aalto", "given": "S." }, "orcid": "0000-0002-5828-7660" }, { "name": { "family": "Evans", "given": "A. S." }, "orcid": "0000-0003-2638-1334" }, { "name": { "family": "Charmandaris", "given": "V." }, "orcid": "0000-0002-2688-1956" }, { "name": { "family": "Privon", "given": "G. C." }, "orcid": "0000-0003-3474-1125" }, { "id": "Lai-Thomas-S-Y", "name": { "family": "Lai", "given": "T." }, "orcid": "0000-0001-8490-6632" }, { "name": { "family": "Inami", "given": "H." }, "orcid": "0000-0003-4268-0393" }, { "name": { "family": "Linden", "given": "S." }, "orcid": "0000-0002-1000-6081" }, { "id": "Armus-L", "name": { "family": "Armus", "given": "L." }, "orcid": "0000-0003-3498-2973" }, { "name": { "family": "Diaz-Santos", "given": "T." }, "orcid": "0000-0003-0699-6083" }, { "id": "Appleton-Philip-N", "name": { "family": "Appleton", "given": "P." }, "orcid": "0000-0002-7607-8766" }, { "name": { "family": "Barcos-Mu\u00f1oz", "given": "L." }, "orcid": "0000-0003-0057-8892" }, { "name": { "family": "B\u00f6ker", "given": "T." }, "orcid": "0000-0002-5666-7782" }, { "name": { "family": "Larson", "given": "K. L." }, "orcid": "0000-0003-3917-6460" }, { "name": { "family": "Law", "given": "D. R." }, "orcid": "0000-0002-9402-186X" }, { "name": { "family": "Malkan", "given": "M. A." }, "orcid": "0000-0001-6919-1237" }, { "name": { "family": "Medling", "given": "A. M." }, "orcid": "0000-0001-7421-2944" }, { "name": { "family": "Song", "given": "Y." }, "orcid": "0000-0002-3139-3041" }, { "name": { "family": "U", "given": "V." }, "orcid": "0000-0002-1912-0024" }, { "name": { "family": "van der Werf", "given": "P." }, "orcid": "0000-0001-5434-5942" }, { "name": { "family": "Bohn", "given": "T." }, "orcid": "0000-0002-4375-254X" }, { "name": { "family": "Brown", "given": "M. J. I." }, "orcid": "0000-0002-1207-9137" }, { "name": { "family": "Finnerty", "given": "L." }, "orcid": "0000-0002-1392-0768" }, { "name": { "family": "Hayward", "given": "C." }, "orcid": "0000-0003-4073-3236" }, { "id": "Howell-Jiustin-H", "name": { "family": "Howell", "given": "J." }, "orcid": "0000-0001-6028-8059" }, { "name": { "family": "Iwasawa", "given": "K." }, "orcid": "0000-0002-4923-3281" }, { "name": { "family": "Kemper", "given": "F." }, "orcid": "0000-0003-2743-8240" }, { "name": { "family": "Marshall", "given": "J." }, "orcid": "0000-0001-7712-8465" }, { "id": "Mazzarella-Joseph-M", "name": { "family": "Mazzarella", "given": "J. M." }, "orcid": "0000-0002-8204-8619" }, { "name": { "family": "McKinney", "given": "J." }, "orcid": "0000-0002-6149-8178" }, { "name": { "family": "Muller-Sanchez", "given": "F." }, "orcid": "0000-0002-2713-0628" }, { "name": { "family": "Murphy", "given": "E. J." }, "orcid": "0000-0001-7089-7325" }, { "name": { "family": "Sanders", "given": "D." }, "orcid": "0000-0002-1233-9998" }, { "id": "Soifer-B-T", "name": { "family": "Soifer", "given": "B. T." }, "orcid": "0000-0002-8112-1132" }, { "name": { "family": "Stierwalt", "given": "S." }, "orcid": "0000-0002-2596-8531" }, { "id": "Surace-Jason-A", "name": { "family": "Surace", "given": "J." }, "orcid": "0000-0001-7291-0087" } ] }, "title": "GOALS-JWST: Pulling Back the Curtain on the AGN and Star Formation in VV 114", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nWe thank the referee for their helpful comments. This work is based on observations made with the NASA/ESA/CSA JWST. The research was supported by NASA grant JWST-ERS-01328. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. The specific observations analysed can be accessed via 10.17909/yqk1-jr92. V.U. acknowledges funding support from NASA Astrophysics Data Analysis Program (ADAP) grant 80NSSC20K0450. The Flatiron Institute is supported by the Simons Foundation. A.M.M. acknowledges support from the National Science Foundation under grant No. 2009416. A.S.E. and S.L. acknowledge support from NASA grants HST-GO15472 and HST-GO16914. Y.S. was funded in part by the NSF through the Grote Reber Fellowship Program administered by Associated Universities, Inc./National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. F.M-S. acknowledges support from NASA through ADAP award 80NSSC19K1096. S.A. gratefully acknowledges support from an ERC Advanced grant 789410, from the Swedish Research Council and from the Knut and Alice Wallenberg (KAW) Foundation. S.A. gratefully acknowledges John Black for helpful discussions. K.I. acknowledges support by the Spanish MCIN under grant PID2019-105510GB-C33/AEI/10.13039/501100011033. This work was also partly supported by the Spanish program Unidad de Excelencia Mara de Maeztu CEX2020-001058-M, financed by MCIN/AEI/10.13039/501100011033. The computations presented here were conducted through Carnegie's partnership in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. Finally, this research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. \n\nFacilities: JWST (NIRCam - , NIRSpec and MIRI). -\n\n

Published - Rich_2023_ApJL_944_L50.pdf

", "abstract": "We present results from the James Webb Space Telescope Director's Discretionary Time Early Release Science program 1328 targeting the nearby, luminous infrared galaxy, VV 114. We use the MIRI and NIRSpec instruments to obtain integral-field spectroscopy of the heavily obscured eastern nucleus (V114E) and surrounding regions. The spatially resolved, high-resolution spectra reveal the physical conditions in the gas and dust over a projected area of 2\u20133 kpc that includes the two brightest IR sources, the NE and SW cores. Our observations show for the first time spectroscopic evidence that the SW core hosts an active galactic nucleus as evidenced by its very low 6.2 \u03bcm and 3.3 \u03bcm polycyclic aromatic hydrocarbon equivalent widths (0.12 and 0.017 \u03bcm, respectively) and mid- and near-IR colors. Our observations of the NE core show signs of deeply embedded star formation including absorption features due to aliphatic hydrocarbons, large quantities of amorphous silicates, as well as HCN due to cool gas along the line of sight. We detect elevated [Fe ii]/Pf\u03b1 consistent with extended shocks coincident with enhanced emission from warm H2, far from the IR-bright cores and clumps. We also identify broadening and multiple kinematic components in both H2 and fine structure lines caused by outflows and previously identified tidal features.", "date": "2023-02-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "944", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. L50", "id_number": "CaltechAUTHORS:20230321-821389800.53", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230321-821389800.53", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JWST-ERS-01328" }, { "agency": "NASA", "grant_number": "NAS 5-03127" }, { "agency": "NASA", "grant_number": "80NSSC20K0450" }, { "agency": "Simons Foundation" }, { "agency": "NSF", "grant_number": "AST-2009416" }, { "agency": "NASA", "grant_number": "HST-GO15472" }, { "agency": "NASA", "grant_number": "HST-GO16914" }, { "agency": "National Radio Astronomy Observatory" }, { "agency": "NASA", "grant_number": "80NSSC19K1096" }, { "agency": "European Research Council (ERC)", "grant_number": "789410" }, { "agency": "Swedish Research Council" }, { "agency": "Knut and Alice Wallenberg Foundation" }, { "agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)", "grant_number": "PID2019-105510GB-C33/AEI/10.13039/501100011033" }, { "agency": "Unidad de Excelencia Mar\u00eda de Maeztu", "grant_number": "CEX2020-001058-M" }, { "agency": "Ministerio de Ciencia e Innovaci\u00f3n (MICINN)", "grant_number": "MCIN/AEI/10.13039/501100011033" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Infrared-Processing-and-Analysis-Center-(IPAC)" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Physics-Mathematics-and-Astronomy" } ] }, "doi": "10.3847/2041-8213/acb2b8", "primary_object": { "basename": "Rich_2023_ApJL_944_L50.pdf", "url": "https://authors.library.caltech.edu/records/a1mkq-n6960/files/Rich_2023_ApJL_944_L50.pdf" }, "pub_year": "2023", "author_list": "Rich, J.; Aalto, S.; et al." }, { "id": "https://authors.library.caltech.edu/records/vpt1p-54010", "eprint_status": "archive", "datestamp": "2024-05-02 17:21:16", "lastmod": "2024-05-02 17:21:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McNicholas-Brendon-J", "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Nie-Cherish", "name": { "family": "Nie", "given": "Cherish" }, "orcid": "0000-0002-3758-9950" }, { "id": "Jose-Anex", "name": { "family": "Jose", "given": "Anex" }, "orcid": "0000-0002-4924-7886" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Takase-Michael-K", "name": { "family": "Takase", "given": "Michael K." }, "orcid": "0000-0001-8365-3645" }, { "id": "Henling-Larry-M", "name": { "family": "Henling", "given": "Larry M." } }, { "id": "Barth-Alexandra-T", "name": { "family": "Barth", "given": "Alexandra T." }, "orcid": "0000-0002-1813-4029" }, { "id": "Amaolo-Alessio", "name": { "family": "Amaolo", "given": "Alessio" }, "orcid": "0000-0002-9973-6872" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" }, { "id": "Solomon-Edward-I", "name": { "family": "Solomon", "given": "Edward I." }, "orcid": "0000-0003-0291-3199" }, { "id": "Winkler-J-R", "name": { "family": "Winkler", "given": "Jay R." }, "orcid": "0000-0002-4453-9716" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Despagnet-Ayoub-Emmanuelle", "name": { "family": "Despagnet-Ayoub", "given": "Emmanuelle" }, "orcid": "0000-0002-9013-7574" } ] }, "title": "Boronated Cyanometallates", "ispublished": "pub", "full_text_status": "public", "keywords": "Inorganic Chemistry; Physical and Theoretical Chemistry", "note": "

© 2022 American Chemical Society.

\n\n

We dedicate this paper to the memory of Bob Grubbs, a great scientist and dear friend, who urged (ordered!) three of us (H.B.G., B.J.M., and E.D.-A.) to develop new redox complexes for use in nonaqueous redox flow batteries. After considering various options, we began work on boronated cyanometallates. We acknowledge the X-ray Crystallography Facility in the Beckman Institute at Caltech and the Dow Next Generation Instrumentation Grant for X-ray structure collection. R.G.H. gratefully acknowledges financial support from Caltech and the Dow Next Generation Educator Fund. EPR spectroscopy was performed in the Caltech EPR facility, which is also supported by the Beckman Institute and the Dow Next Generation Educator Fund. We thank David van der Velde for assistance in interpreting the NMR data. We thank Wesley W. Kramer and Brian C. Sanders for general discussion and Nathanael P. Kazmierczak for helpful discussions on the absorbance and MCD simulation. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. We thank Julius J. Oppenheim for assistance with calculations.

\n\n

This work was supported by the National Science Foundation (Grant CHE-1763429). Additional funding was provided by two Arthur A. Noyes SURF Fellowships (to C.N. and A.A.) and the Beckman Institute Laser Resource Center supported by the Arnold and Mabel Beckman Foundation.

\n\n

All authors have given approval to the final version of the manuscript.

\n\n
\n\n
\n

Accession Codes

\n

CCDC 2145310–2145321, 2145325, and 2145326 contain the supplementary crystallographic data for this paper.

\n\n

The authors declare no competing financial interest.

", "abstract": "

Thirteen boronated cyanometallates [M(CN-BR3)6]3/4/5– [M = Cr, Mn, Fe, Ru, Os; BR3 = BPh3, B(2,4,6,-F3C6H2)3, B(C6F5)3] and one metalloboratonitrile [Cr(NC-BPh3)6]3– have been characterized by X-ray crystallography and spectroscopy [UV–vis–near-IR, NMR, IR, spectroelectrochemistry, and magnetic circular dichroism (MCD)]; CASSCF+NEVPT2 methods were employed in calculations of electronic structures. For (t2g)5 electronic configurations, the lowest-energy ligand-to-metal charge-transfer (LMCT) absorptions and MCD C-terms in the spectra of boronated species have been assigned to transitions from cyanide π + B–C borane σ orbitals. CASSCF+NEVPT2 calculations including t1u and t2u orbitals reproduced t1u/t2u → t2g excitation energies. Many [M(CN-BR3)6]3/4– complexes exhibited highly electrochemically reversible redox couples. Notably, the reduction formal potentials of all five [M(CN-B(C6F5)3)6]3– anions scale with the LMCT energies, and Mn(I) and Cr(II) compounds, [K(18-crown-6)]5[Mn(CN-B(C6F5)3)6] and [K(18-crown-6)]4[Cr(CN-B(C6F5)3)6], are surprisingly stable. Continuous-wave and pulsed electron paramagnetic resonance (EPR; hyperfine sublevel correlation) spectra were collected for all Cr(III) complexes; as expected, 14N hyperfine splittings are greater for (Ph4As)3[Cr(NC-BPh3)6] than for (Ph4As)3[Cr(CN-BPh3)6].

", "date": "2023-02-20", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "62", "number": "7", "publisher": "American Chemical Society", "pagerange": "2959-2981", "issn": "0020-1669", "official_url": "https://authors.library.caltech.edu/records/vpt1p-54010", "funders": { "items": [ { "grant_number": "CHE-1763429" }, { "grant_number": "Summer Undergraduate Research Fellowship" }, {}, {}, { "grant_number": "Dow Next Generation Educator Fund" }, {} ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.2c03066", "primary_object": { "basename": "ic2c03066_si_001.pdf", "url": "https://authors.library.caltech.edu/records/vpt1p-54010/files/ic2c03066_si_001.pdf" }, "pub_year": "2023", "author_list": "McNicholas, Brendon J.; Nie, Cherish; et al." }, { "id": "https://authors.library.caltech.edu/records/eq7gj-be636", "eprint_id": 119514, "eprint_status": "archive", "datestamp": "2023-08-22 18:59:09", "lastmod": "2025-04-25 02:43:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wilding-John-D", "name": { "family": "Wilding", "given": "John D." }, "orcid": "0000-0002-0914-2078" }, { "id": "Zhu-Weiqiang", "name": { "family": "Zhu", "given": "Weiqiang" }, "orcid": "0000-0003-2889-1493" }, { "id": "Ross-Z-E", "name": { "family": "Ross", "given": "Zachary E." }, "orcid": "0000-0002-6343-8400" }, { "id": "Jackson-J-M", "name": { "family": "Jackson", "given": "Jennifer M." }, "orcid": "0000-0002-8256-6336" } ] }, "title": "The magmatic web beneath Hawai'i", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "The authors acknowledge comments by A. Flinders and an anonymous reviewer that substantially improved the manuscript. The facilities of IRIS Data Services, and specifically the IRIS Data Management Center (DMC), were used for access to waveforms, related metadata, and/or derived products used in this study. IRIS Data Services are funded through the Seismological Facilities for the Advancement of Geoscience (SAGE) Award of the National Science Foundation under cooperative support agreement EAR-1851048. The computations presented in this work were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. \n\nZ.E.R. and J.D.W. received support from NSF award EAR-2034167. J.M.J. acknowledges the JPL Strategic Research & Technology Development Program, \"Venus Science Into The Next Decade.\" \n\nAuthor contributions: W.Z. performed phase picking. Z.E.R. and J.D.W. performed quality control on the phase picks and constructed the catalog. Z.E.R. and W.Z. performed earthquake relocation. J.D.W. performed the frequency index calculations. J.D.W., W.Z., Z.E.R., and J.M.J. contributed to data analysis and writing. All authors contributed to the revised version of the manuscript. \n\nData and materials availability: Seismic data are publicly available from the IRIS DMC. The seismicity catalog developed in this study will be made publicly available. \n\nAll authors declare no competing interests.", "abstract": "The deep magmatic architecture of the Hawaiian volcanic system is central to understanding the transport of magma from the upper mantle to the individual volcanoes. We leverage advances in earthquake monitoring with deep learning algorithms to image the structures underlying a major mantle earthquake swarm of nearly 200,000 events that rapidly accelerated after the 2018 K\u012blauea caldera collapse. At depths of 36 to 43 kilometers, we resolve a 15-kilometers-long collection of near-horizontal sheeted structures that we identify as a sill complex. These sills connect to the lower depths of K\u012blauea's plumbing by a 25-kilometers-long belt of seismicity. Additionally, a column of seismicity links the sill complex to a shallow d\u00e9collement near Mauna Loa. These findings implicate the mantle sill complex as a nexus for magma transport beneath Hawai'i and furthermore indicate widespread magmatic connectivity in the volcanic system.", "date": "2023-02-03", "date_type": "published", "publication": "Science", "volume": "379", "number": "6631", "publisher": "American Association for the Advancement of Science", "pagerange": "462-468", "id_number": "CaltechAUTHORS:20230227-611905000.2", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230227-611905000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-2034167" }, { "agency": "JPL Strategic Research and Technology Development Program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" } ] }, "doi": "10.1126/science.ade5755", "pub_year": "2023", "author_list": "Wilding, John D.; Zhu, Weiqiang; et al." }, { "id": "https://authors.library.caltech.edu/records/gh9hq-bqx27", "eprint_id": 120237, "eprint_status": "archive", "datestamp": "2023-08-22 18:55:18", "lastmod": "2025-11-22 03:39:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ren-Bin-B", "name": { "family": "Ren", "given": "Bin B." }, "orcid": "0000-0003-1698-9696" }, { "id": "Wallack-Nicole-L", "name": { "family": "Wallack", "given": "Nicole L." }, "orcid": "0000-0003-0354-0187" }, { "id": "Hurt-Spencer-A", "name": { "family": "Hurt", "given": "Spencer A." }, "orcid": "0000-0002-6903-9080" }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "id": "Carter-Aarynn-L", "name": { "family": "Carter", "given": "Aarynn L." }, "orcid": "0000-0001-5365-4815" }, { "id": "Echeverri-Daniel", "name": { "family": "Echeverri", "given": "Daniel" }, "orcid": "0000-0002-1583-2040" }, { "id": "Llop-Sayson-Jorge-D", "name": { "family": "Llop-Sayson", "given": "Jorge" }, "orcid": "0000-0002-3414-784X" }, { "id": "Meshkat-Tiffany", "name": { "family": "Meshkat", "given": "Tiffany" }, "orcid": "0000-0001-6126-2467" }, { "id": "Oppenheimer-Rebecca", "name": { "family": "Oppenheimer", "given": "Rebecca" }, "orcid": "0000-0001-7130-7681" }, { "id": "Aguilar-Jonathan", "name": { "family": "Aguilar", "given": "Jonathan" }, "orcid": "0000-0003-3184-0873" }, { "id": "Cady-Eric-J", "name": { "family": "Cady", "given": "Eric" }, "orcid": "0000-0002-8789-2931" }, { "id": "Choquet-\u00c9lodie", "name": { "family": "Choquet", "given": "\u00c9lodie" }, "orcid": "0000-0002-9173-0740" }, { "id": "Ruane-Garreth-J", "name": { "family": "Ruane", "given": "Garreth" }, "orcid": "0000-0003-4769-1665" }, { "id": "Vasisht-Gautam", "name": { "family": "Vasisht", "given": "Gautam" }, "orcid": "0000-0002-1871-6264" }, { "id": "Ygouf-Marie", "name": { "family": "Ygouf", "given": "Marie" }, "orcid": "0000-0001-7591-2731" } ] }, "title": "Planet search with the Keck/NIRC2 vortex coronagraph in the M\u209b band for Vega", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 The Authors 2023. Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This article is published in open access under the Subscribe to Open model. Subscribe to A&A to support open access publication. \n\nWe thank the anonymous referee for their constructive comments that increased the clarity and reproducibility of this paper. This research is partially supported by NASA ROSES XRP, award 80NSSC19K0294. B.B.R. has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (PRO-TOPLANETS, grant agreement No. 101002188). \u00c9.C. has received funding from the European Research Council (ERC) under the European Union's Horizon Europe research and innovation programme (ESCAPE, grant agreement No 101044152). Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W.M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. Part of the computations presented here was conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.\n\n

Published - aa44485-22.pdf

", "abstract": "Context. Gaps in circumstellar disks can signal the existence of planetary perturbers, making such systems preferred targets for direct imaging observations of exoplanets. \n\nAims. Being one of the brightest and closest stars to the Sun, the photometric standard star Vega hosts a two-belt debris disk structure. Together with the fact that its planetary system is being viewed nearly face-on, Vega has been one of the prime targets for planet imaging efforts. \n\nMethods. Using the vector vortex coronagraph on Keck/NIRC2 in the M\u209b band at 4.67 \u03bcm, we report the planet detection limits from 1 au to 22 au for Vega with an on-target time of 1.8 h. \n\nResults. We reach a 3 M_(Jupiter) limit outward of 12 au, which is nearly an order of magnitude deeper than for other existing studies. Combining our observations with existing radial velocity studies, we can confidently rule out the existence of companions more than ~8 M_(Jupiter) from 22 au down to 0.1 au for Vega. Interior and exterior to ~4 au, this combined approach reaches planet detection limits down to ~2\u20133 M_(Jupiter) using radial velocity and direct imaging, respectively. \n\nConclusions. By reaching multi-Jupiter mass detection limits, our results are expected to be complemented by the planet imaging of Vega in the upcoming observations using the James Webb Space Telescope to obtain a more holistic understanding of the planetary system configuration around Vega.", "date": "2023-02", "date_type": "published", "publication": "Astronomy and Astrophysics", "volume": "670", "publisher": "EDP Sciences", "pagerange": "Art. No. A162", "id_number": "CaltechAUTHORS:20230321-821389800.40", "issn": "0004-6361", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230321-821389800.40", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC19K0294" }, { "agency": "European Research Council (ERC)", "grant_number": "101002188" }, { "agency": "European Research Council (ERC)", "grant_number": "101044152" }, { "agency": "W. M. Keck Foundation" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1051/0004-6361/202244485", "primary_object": { "basename": "aa44485-22.pdf", "url": "https://authors.library.caltech.edu/records/gh9hq-bqx27/files/aa44485-22.pdf" }, "pub_year": "2023", "author_list": "Ren, Bin B.; Wallack, Nicole L.; et al." }, { "id": "https://authors.library.caltech.edu/records/814ce-fva43", "eprint_id": 120038, "eprint_status": "archive", "datestamp": "2023-08-22 18:54:41", "lastmod": "2025-11-22 04:09:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Braghiere-Renato-K", "name": { "family": "Braghiere", "given": "Renato K." }, "orcid": "0000-0002-7722-717X" }, { "id": "Fisher-Joshua-B", "name": { "family": "Fisher", "given": "Joshua B." }, "orcid": "0000-0003-4734-9085" }, { "id": "Miner-Kimberley-R", "name": { "family": "Miner", "given": "Kimberley R." }, "orcid": "0000-0002-1006-1283" }, { "id": "Miller-Charles-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Worden-John-R", "name": { "family": "Worden", "given": "John R." }, "orcid": "0000-0003-0257-9549" }, { "id": "Schimel-David-S", "name": { "family": "Schimel", "given": "David S." }, "orcid": "0000-0003-3473-8065" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Tipping point in North American Arctic-Boreal carbon sink persists in new generation Earth system models despite reduced uncertainty", "ispublished": "pub", "full_text_status": "public", "keywords": "Public Health, Environmental and Occupational Health; General Environmental Science; Renewable Energy, Sustainability and the Environment", "note": "\u00a9 2023 The Author(s). Published by IOP Publishing Ltd.\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nSpecial Issue: Resiliency and Vulnerability of Arctic and Boreal Ecosystems to Environmental Change: Advances and Outcomes of ABoVE (the Arctic Boreal Vulnerability Experiment) \n\nThis study was part of the NASA Arctic-Boreal Vulnerability Experiment (ABoVE). RKB and JBF were supported through funding from Phase 2 of NASA ABoVE (NNX15AV77A). Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D004). California Institute of Technology. Government sponsorship acknowledged. This research used resources of the NASA ABoVE program. We acknowledge support from the NASA ABoVE (incl. 80NSSC22K1245, NNX17AD69A) and ILAMB communities. This work was supported in part by Resnick Sustainability Institute. \n\nAuthor contribution. RKB planned and designed the research. JBF supervised and acquired funding. RKB performed the research, data analysis, collection, and interpretation, as well as wrote the original draft and final manuscript with input from all authors. \n\nData availability statement. The data that support the findings of this study are openly available. The CMIP6 data simulations performed by various modeling groups are available from the CMIP6 archive (https://esgf-node.llnl.gov/search/cmip6). The ILAMB package can be downloaded from (https://github.com/rubisco-sfa/ILAMB). All ILAMB plots are available from (https://braghiere.github.io/). \n\nThe authors declare no competing interests.\n\n

Published - Braghiere_2023_Environ._Res._Lett._18_025008.pdf

", "abstract": "Estimating the impacts of climate change on the global carbon cycle relies on projections from Earth system models (ESMs). While ESMs currently project large warming in the high northern latitudes, the magnitude and sign of the future carbon balance of Arctic-Boreal ecosystems are highly uncertain. The new generation of increased complexity ESMs in the Intergovernmental Panel on Climate Change Sixth Assessment Report (IPCC AR6) is intended to improve future climate projections. Here, we benchmark the Coupled Model Intercomparison Project (CMIP) 5 and 6 (8 CMIP5 members and 12 CMIP6 members) with the International Land Model Benchmarking (ILAMB) tool over the region of NASA's Arctic-Boreal vulnerability experiment (ABoVE) in North America. We show that the projected average net biome production (NBP) in 2100 from CMIP6 is higher than that from CMIP5 in the ABoVE domain, despite the model spread being slightly narrower. Overall, CMIP6 shows better agreement with contemporary observed carbon cycle variables (photosynthesis, respiration, biomass) than CMIP5, except for soil carbon and turnover time. Although both CMIP ensemble members project the ABoVE domain will remain a carbon sink by the end of the 21st century, the sink strength in CMIP6 increases with CO\u2082 emissions. CMIP5 and CMIP6 ensembles indicate a tipping point defined here as a negative inflection point in the NBP curve by 2050\u20132080 independently of the shared socioeconomic pathway (SSP) for CMIP6 or representative concentration pathway (RCP) for CMIP5. The model ensembles therefore suggest that, if the carbon sink strength keeps declining throughout the 21st century, the Arctic-Boreal ecosystems in North America may become a carbon source over the next century.", "date": "2023-02", "date_type": "published", "publication": "Environmental Research Letters", "volume": "18", "number": "2", "publisher": "IOP", "pagerange": "Art. No. 025008", "id_number": "CaltechAUTHORS:20230314-845495900.66", "issn": "1748-9326", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230314-845495900.66", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AV77A" }, { "agency": "NASA", "grant_number": "80NM0018D004" }, { "agency": "NASA", "grant_number": "80NSSC22K1245" }, { "agency": "NASA", "grant_number": "NNX17AD69A" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1088/1748-9326/acb226", "primary_object": { "basename": "Braghiere_2023_Environ._Res._Lett._18_025008.pdf", "url": "https://authors.library.caltech.edu/records/814ce-fva43/files/Braghiere_2023_Environ._Res._Lett._18_025008.pdf" }, "pub_year": "2023", "author_list": "Braghiere, Renato K.; Fisher, Joshua B.; et al." }, { "id": "https://authors.library.caltech.edu/records/czj7n-6et27", "eprint_id": 118672, "eprint_status": "archive", "datestamp": "2023-08-22 18:50:49", "lastmod": "2023-10-24 23:27:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cetiner-Jaclyn-E-P", "name": { "family": "Cetiner", "given": "Jaclyn E. P." }, "orcid": "0000-0001-7879-059X" }, { "id": "Berelson-William-M", "name": { "family": "Berelson", "given": "William M." }, "orcid": "0000-0002-1526-3802" }, { "id": "Rollins-Nick-E", "name": { "family": "Rollins", "given": "Nick E." } }, { "id": "Barnhart-Holly-A", "name": { "family": "Barnhart", "given": "Holly A." }, "orcid": "0000-0002-0842-9464" }, { "id": "Liu-Xuewu", "name": { "family": "Liu", "given": "Xuewu" }, "orcid": "0000-0003-2896-3063" }, { "id": "Dong-Sijia-S", "name": { "family": "Dong", "given": "Sijia" }, "orcid": "0000-0002-5811-9333" }, { "id": "Byrne-Robert-H", "name": { "family": "Byrne", "given": "Robert H." }, "orcid": "0000-0003-0726-0131" }, { "id": "Adkins-J-F", "name": { "family": "Adkins", "given": "Jess F." }, "orcid": "0000-0002-3174-5190" } ] }, "title": "Novel device to collect deep-sea porewater in situ: A focus on benthic carbonate chemistry", "ispublished": "pub", "full_text_status": "public", "keywords": "Ocean Engineering", "note": "\u00a9 2022 The Authors. Limnology and Oceanography: Methods published by Wiley Periodicals LLC on behalf of Association for the Sciences of Limnology and Oceanography. \nThis is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. \n\nThis work was supported by NSF Ocean Acidification (OCE-1834475). J.E.P.C. thanks the USC Wrigley Institute for Environmental Studies for PhD funding. H.A.B. thanks the Resnick Sustainability Institute for PhD funding. The authors would like to thank the editors, as well as David Burdige and an anonymous reviewer for their helpful questions and comments that improved the manuscript. The authors would like to sincerely thank Kalla Fleger for alkalinity and pH measurements on board; Matthew Quinan for dissolved silicate measurements; Rucha Wani and Emma Johnson for their contributions to the SIPR team at sea; and the science party, captain, and crew of the R/V Sally Ride SR2113 cruise. We also appreciate the discussions and laboratory support from Abby Lunstrum and assistance with silicate measurements from Doug Hammond. The authors also thank the Southern California Marine Institute and the captain and crew of the R/V Yellowfin for allowing us many SIPR test deployments. \n\nData availability statement. All data used in this paper are presented in the figures. Data sets are available upon request.\n\n

Published - Limnology___Ocean_Methods_-_2022_-_Cetiner_-_Novel_device_to_collect_deep\u2010sea_porewater_in_situ__A_focus_on_benthic.pdf

", "abstract": "We have designed, built, tested, and deployed a novel device to extract porewater from deep-sea sediments in situ, constructed to work with a standard multicorer. Despite the importance of porewater measurements for numerous applications, many sampling artifacts can bias data and interpretation during traditional porewater processing from shipboard-processed cores. A well-documented artifact occurs in deep-sea porewater when carbonate precipitates during core recovery as a function of temperature and pressure changes, while porewater is in contact with sediment grains before filtration, thereby lowering porewater alkalinity and dissolved inorganic carbon (DIC). Here, we present a novel device built to obviate these sampling artifacts by filtering porewater in situ on the seafloor, with a focus near the sediment\u2013water interface on cm-scale resolution, to obtain accurate porewater profiles. We document 1\u201310% alkalinity loss in shipboard-processed sediment cores compared to porewater filtered in situ, at depths of 1600\u20133200\u2009m. We also show that alkalinity loss is a function of both weight % sedimentary CaCO\u2083 and water column depth. The average ratio of alkalinity loss to DIC loss in shipboard-processed sediment cores relative to in situ porewater is 2.2, consistent with the signal expected from carbonate precipitation. In addition to collecting porewater for defining natural profiles, we also conducted the first in situ dissolution experiments within the sediment column using isotopically labeled calcite. We present evidence of successful deployments of this device on and adjacent to the Cocos Ridge in the Eastern Equatorial Pacific across a range of depths and calcite saturation states.", "date": "2023-02", "date_type": "published", "publication": "Limnology and Oceanography: Methods", "volume": "21", "number": "2", "publisher": "American Society for Limnology and Oceanography", "pagerange": "82-97", "id_number": "CaltechAUTHORS:20230104-586485300.11", "issn": "1541-5856", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230104-586485300.11", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OCE-1834475" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of Southern California" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/lom3.10530", "primary_object": { "basename": "Limnology___Ocean_Methods_-_2022_-_Cetiner_-_Novel_device_to_collect_deep\u2010sea_porewater_in_situ__A_focus_on_benthic.pdf", "url": "https://authors.library.caltech.edu/records/czj7n-6et27/files/Limnology___Ocean_Methods_-_2022_-_Cetiner_-_Novel_device_to_collect_deep\u2010sea_porewater_in_situ__A_focus_on_benthic.pdf" }, "pub_year": "2023", "author_list": "Cetiner, Jaclyn E. P.; Berelson, William M.; et al." }, { "id": "https://authors.library.caltech.edu/records/as9rz-4ke33", "eprint_id": 119356, "eprint_status": "archive", "datestamp": "2024-03-15 16:01:25", "lastmod": "2024-03-15 16:01:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ibrahim-Ammar-F", "name": { "family": "Ibrahim", "given": "Ammar F." }, "orcid": "0000-0002-5465-1525" }, { "id": "Garrido-Barros-Pablo", "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Electrocatalytic Nitrogen Reduction on a Molybdenum Complex Bearing a PNP Pincer Ligand", "ispublished": "pub", "full_text_status": "public", "keywords": "Catalysis; General Chemistry", "note": "\u00a9 2022 American Chemical Society. \n\nWe thank the Dow Next Generation Educator Funds and Instrumentation Grants for their support of the NMR facility at Caltech. We also thank the Resnick Water and Environment Laboratory and the Molecular Materials Resource Center at Caltech for the use of their instrumentation. The authors thank Dr. Michael Takase for assistance with X-ray crystallography. We thank the following funding agencies: Department of Energy, Office of Basic Energy Sciences (DOE-0235032), Catalysis Science Program (for the development and applications of PCET mediators) and National Institutes of Health (R01 GM-075757) (for fundamental studies of N\u2082R catalysis). P.G.B. thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship.", "abstract": "Electrocatalytic nitrogen reduction (N2R) mediated by well-defined molecular catalysts is poorly developed by comparison with other reductive electrocatalytic transformations. Herein, we explore the viability of electrocatalytic N\u2082R mediated by a molecular Mo-PNP complex. A careful choice of acid, electrode material, and electrolyte mitigates electrode-mediated HER under direct electrolysis and affords up to 11.7 equiv of NH\u2083 (Faradaic efficiency < 43%) at \u22121.89 V versus Fc\u207a/Fc. The addition of a proton-coupled electron transfer (PCET) mediator has no effect. The data presented are rationalized by an initial electron transfer (ET) that sets the applied bias needed and further reveal an important impact of [Mo] concentration, thereby pointing to potential bimolecular steps (e.g., N\u2082 splitting) as previously proposed during chemically driven N\u2082R catalysis. Finally, facile reductive protonation of [Mo(N)Br(\u1d34PNP)] with pyridinium acids is demonstrated.", "date": "2023-01-26", "date_type": "published", "publication": "ACS Catalysis", "volume": "13", "number": "1", "publisher": "American Chemical Society", "pagerange": "72-78", "id_number": "CaltechAUTHORS:20230221-18374200.4", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-18374200.4", "funders": { "items": [ { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "NIH", "grant_number": "R01 GM-075757" }, { "agency": "Fundaci\u00f3n Ram\u00f3n Areces" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscatal.2c04769", "pmcid": "PMC10939127", "primary_object": { "basename": "nihms-1916811.pdf", "url": "https://authors.library.caltech.edu/records/as9rz-4ke33/files/nihms-1916811.pdf" }, "pub_year": "2023", "author_list": "Ibrahim, Ammar F.; Garrido-Barros, Pablo; et al." }, { "id": "https://authors.library.caltech.edu/records/1mgra-q0g13", "eprint_id": 118590, "eprint_status": "archive", "datestamp": "2023-08-20 09:04:39", "lastmod": "2025-04-25 22:45:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Choi-Chungseok", "name": { "family": "Choi", "given": "Chungseok" }, "orcid": "0000-0001-9169-1393" }, { "id": "Wang-Xiaoxiao", "name": { "family": "Wang", "given": "Xiaoxiao" }, "orcid": "0000-0001-9596-8759" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Hart-James-L", "name": { "family": "Hart", "given": "James L." } }, { "id": "Rooney-Conor-L", "name": { "family": "Rooney", "given": "Conor L." }, "orcid": "0000-0001-7058-568X" }, { "id": "Harmon-Nia-J", "name": { "family": "Harmon", "given": "Nia J." }, "orcid": "0000-0002-4117-4088" }, { "id": "Sam-Quynh-P", "name": { "family": "Sam", "given": "Quynh P." }, "orcid": "0000-0002-0636-2235" }, { "id": "Cha-Judy-J", "name": { "family": "Cha", "given": "Judy J." }, "orcid": "0000-0002-6346-2814" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Elimelech-Menachem", "name": { "family": "Elimelech", "given": "Menachem" }, "orcid": "0000-0003-4186-1563" }, { "id": "Wang-Hailiang", "name": { "family": "Wang", "given": "Hailiang" }, "orcid": "0000-0003-4409-2034" } ] }, "title": "Efficient electrocatalytic valorization of chlorinated organic water pollutant to ethylene", "ispublished": "pub", "full_text_status": "restricted", "note": "This work (materials synthesis, structural characterization and catalysis work) was primarily supported as part of the Center for Hybrid Approaches in Solar Energy to Liquid Fuels (CHASE), an Energy Innovation Hub funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, under award no. DE-SC0021173 (H.W.). Computational work was supported by the Liquid Sunlight Alliance, which is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award no. DE-SC0021266 (W.A.G.) and an individual fellowship from the Resnick Sustainability Institute at Caltech (S.K.), and used the Extreme Science and Engineering Discovery Environment (XSEDE) for DFT calculations, which is supported by National Science Foundation grant no. ACI-1548562 (W.A.G.). Electrified membrane filtration work was supported by the NSF Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (EEC-1449500; M.E.). STEM and EDX characterizations were supported by the NSF career award no. 1749742 (J.J.C.). We thank J. Lee and J. D. Fortner (Department of Chemical and Environmental Engineering, Yale University) for providing graphene oxide.", "abstract": "Electrochemistry can provide an efficient and sustainable way to treat environmental waters polluted by chlorinated organic compounds. However, the electrochemical valorization of 1,2-dichloroethane (DCA) is currently challenged by the lack of a catalyst that can selectively convert DCA in aqueous solutions into ethylene. Here we report a catalyst comprising cobalt phthalocyanine molecules assembled on multiwalled carbon nanotubes that can electrochemically decompose aqueous DCA with high current and energy efficiencies. Ethylene is produced at high rates with unprecedented ~100% Faradaic efficiency across wide electrode potential and reactant concentration ranges. Kinetic studies and density functional theory calculations reveal that the rate-determining step is the first C\u2013Cl bond breaking, which does not involve protons\u2014a key mechanistic feature that enables cobalt phthalocyanine/carbon nanotube to efficiently catalyse DCA dechlorination and suppress the hydrogen evolution reaction. The nanotubular structure of the catalyst enables us to shape it into a flow-through electrified membrane, which we have used to demonstrate >95% DCA removal from simulated water samples with environmentally relevant DCA and electrolyte concentrations.", "date": "2023-01-23", "date_type": "published", "publication": "Nature Nanotechnology", "volume": "18", "number": "2", "publisher": "Nature Publishing Group", "pagerange": "160-167", "id_number": "CaltechAUTHORS:20221222-210402258", "issn": "1748-3395", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221222-210402258", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021173" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "NSF", "grant_number": "EEC-1449500" }, { "agency": "NSF", "grant_number": "CBET-1749742" } ] }, "other_numbering_system": { "items": [ { "id": "1552", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1038/s41565-022-01277-z", "pub_year": "2023", "author_list": "Choi, Chungseok; Wang, Xiaoxiao; et al." }, { "id": "https://authors.library.caltech.edu/records/af36s-kkk94", "eprint_id": 119370, "eprint_status": "archive", "datestamp": "2023-08-22 18:45:55", "lastmod": "2023-10-25 14:39:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Klein-Isabel-M", "name": { "family": "Klein", "given": "Isabel M." }, "orcid": "0000-0001-6134-6732" }, { "id": "Krotz-Alex", "name": { "family": "Krotz", "given": "Alex" }, "orcid": "0000-0001-8189-7902" }, { "id": "Lee-Wonseok", "name": { "family": "Lee", "given": "Wonseok" }, "orcid": "0000-0003-1077-0511" }, { "id": "Michelsen-Jonathan-M", "name": { "family": "Michelsen", "given": "Jonathan M." } }, { "id": "Cushing-S-K", "name": { "family": "Cushing", "given": "Scott K." }, "orcid": "0000-0003-3538-2259" } ] }, "title": "Ab Initio Calculations of XUV Ground and Excited States for First-Row Transition Metal Oxides", "ispublished": "pub", "full_text_status": "public", "keywords": "Surfaces, Coatings and Films; Physical and Theoretical Chemistry; General Energy; Electronic, Optical and Magnetic Materials", "note": "\u00a9 2023 American Chemical Society. \n\nAny opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the United States Air Force. The computations presented here were conducted in the Resnick High Performance Computing Center. \n\nThis material is based upon work supported by the Air Force Office of Scientific Research under award number FA9550-21-1-0022. I.M.K. was supported by an NSF Graduate Research Fellowship (DGE-1745301). W.L. was supported by the Korea Foundation for Advanced Studies (KFAS) Graduate Research Fellowship. The Resnick High Performance Computing Center is a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. \n\nAuthor Contributions. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.", "abstract": "Transient X-ray spectroscopies have become ubiquitous in studying photoexcited dynamics in solar energy materials due to their sensitivity to carrier occupations and local chemical or structural dynamics. The interpretation of solid-state photoexcited dynamics, however, is complicated by the core\u2013hole perturbation and the resulting many-body dynamics. Here, an ab initio, Bethe\u2013Salpeter equation (BSE) approach is developed that can incorporate photoexcited state effects for solid-state materials. The extreme ultraviolet (XUV) absorption spectra for the ground, photoexcited, and thermally expanded states of first row transition metal oxides\u2500TiO\u2082, \u03b1-Cr\u2082O\u2083, \u03b2-MnO\u2082, \u03b1-Fe\u2082O\u2083, Co\u2083O\u2084, NiO, CuO, and ZnO\u2500are calculated to demonstrate the accuracy of this approach. The theory is used to decompose the core\u2013valence excitons into the separate components of the X-ray transition Hamiltonian for each of the transition metal oxides investigated. The decomposition provides a physical intuition about the origins of XUV spectral features as well as how the spectra will change following photoexcitation. The method is easily generalized to other K, L, M, and N edges to provide a general approach for analyzing transient X-ray absorption or reflection data.", "date": "2023-01-19", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "127", "number": "2", "publisher": "American Chemical Society", "pagerange": "1077-1086", "id_number": "CaltechAUTHORS:20230221-18374200.11", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-18374200.11", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-21-1-0022" }, { "agency": "Korea Foundation for Advanced Studies" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.2c06548", "pub_year": "2023", "author_list": "Klein, Isabel M.; Krotz, Alex; et al." }, { "id": "https://authors.library.caltech.edu/records/trbyb-nm944", "eprint_id": 119182, "eprint_status": "archive", "datestamp": "2023-08-22 18:45:47", "lastmod": "2023-10-24 23:50:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mai-Huanghao", "name": { "family": "Mai", "given": "Huanghao" }, "orcid": "0000-0003-2278-0768" }, { "id": "Zimmer-Matthew-H", "name": { "family": "Zimmer", "given": "Matthew H." }, "orcid": "0000-0002-1437-2636" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Exploring PROTAC Cooperativity with Coarse-Grained Alchemical Methods", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Surfaces, Coatings and Films; Physical and Theoretical Chemistry", "note": "\u00a9 2023 The Authors. Published by American Chemical Society. Attribution 4.0 International (CC BY 4.0) \n\nH.M. thanks William M. Clemons, Jr., Daniel Jacobson, Tomislav Begu\u0161i\u0107, Xuecheng Tao, Marta Gonzalvo, and Lixue Cheng for comments on the manuscript, and Zhen-Gang Wang and Christopher J. Balzer for technical discussions. We gratefully acknowledge support from the National Institutes of Health (NIH) R01GM138845 (8877_CIT, subaward), Amgen Chem-Bio-Engineering Award (CBEA), and DeLogi Trust Science and Technology Grant. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) Bridges computer at the Pittsburgh Supercomputing Center through allocation MCB160013. (67) XSEDE is supported by National Science Foundation grant number ACI-1548562. This work also used computational resources from the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. \n\nThe authors declare no competing financial interest.\n\n

Published - acs.jpcb.2c05795.pdf

Supplemental Material - jp2c05795_si_001.pdf

", "abstract": "Proteolysis targeting chimera (PROTAC) is a novel drug modality that facilitates the degradation of a target protein by inducing proximity with an E3 ligase. In this work, we present a new computational framework to model the cooperativity between PROTAC\u2013E3 binding and PROTAC\u2013target binding principally through protein\u2013protein interactions (PPIs) induced by the PROTAC. Due to the scarcity and low resolution of experimental measurements, the physical and chemical drivers of these non-native PPIs remain to be elucidated. We develop a coarse-grained (CG) approach to model interactions in the target\u2013PROTAC\u2013E3 complexes, which enables converged thermodynamic estimations using alchemical free energy calculation methods despite an unconventional scale of perturbations. With minimal parametrization, we successfully capture fundamental principles of cooperativity, including the optimality of intermediate PROTAC linker lengths that originates from configurational entropy. We qualitatively characterize the dependency of cooperativity on PROTAC linker lengths and protein charges and shapes. Minimal inclusion of sequence- and conformation-specific features in our current force field, however, limits quantitative modeling to reproduce experimental measurements, but further development of the CG model may allow for efficient computational screening to optimize PROTAC cooperativity.", "date": "2023-01-19", "date_type": "published", "publication": "Journal of Physical Chemistry B", "volume": "127", "number": "2", "publisher": "American Chemical Society", "pagerange": "446-455", "id_number": "CaltechAUTHORS:20230209-988069100.19", "issn": "1520-6106", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230209-988069100.19", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01GM138845" }, { "agency": "Amgen" }, { "agency": "Caltech DeLogi Fund" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcb.2c05795", "pmcid": "PMC9869335", "primary_object": { "basename": "acs.jpcb.2c05795.pdf", "url": "https://authors.library.caltech.edu/records/trbyb-nm944/files/acs.jpcb.2c05795.pdf" }, "related_objects": [ { "basename": "jp2c05795_si_001.pdf", "url": "https://authors.library.caltech.edu/records/trbyb-nm944/files/jp2c05795_si_001.pdf" } ], "pub_year": "2023", "author_list": "Mai, Huanghao; Zimmer, Matthew H.; et al." }, { "id": "https://authors.library.caltech.edu/records/pq0c4-5aj21", "eprint_id": 119068, "eprint_status": "archive", "datestamp": "2023-08-22 18:44:56", "lastmod": "2023-10-24 23:49:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zak-Joshua-J", "name": { "family": "Zak", "given": "Joshua J." }, "orcid": "0000-0003-3793-7254" }, { "id": "Zuba-Mateusz", "name": { "family": "Zuba", "given": "Mateusz" }, "orcid": "0000-0002-3209-7922" }, { "id": "Lebens-Higgins-Zachary-W", "name": { "family": "Lebens-Higgins", "given": "Zachary W." } }, { "id": "Huang-Heran", "name": { "family": "Huang", "given": "Heran" } }, { "id": "Crafton-Matthew-J", "name": { "family": "Crafton", "given": "Matthew J." }, "orcid": "0000-0001-7228-5576" }, { "id": "Dalleska-N-F", "name": { "family": "Dalleska", "given": "Nathan F." }, "orcid": "0000-0002-2059-1587" }, { "id": "McCloskey-Bryan-D", "name": { "family": "McCloskey", "given": "Bryan D." }, "orcid": "0000-0001-6599-2336" }, { "id": "Piper-Louis-F-J", "name": { "family": "Piper", "given": "Louis F. J." }, "orcid": "0000-0002-3421-3210" }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Irreversible Anion Oxidation Leads to Dynamic Charge Compensation in the Ru-Poor, Li-Rich Cathode Li\u2082Ru_(0.3)Mn_(0.7)O\u2083", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "This work was supported as part of the Center for Synthetic Control Across Length-scales for Advancing Rechargeables (SCALAR), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award No. DE-SC0019381. J.J.Z. acknowledges support from the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1745301. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. We thank Wanli Yang and Tien-Lin Lee for assistance with the RIXS and HAXPES experiments, respectively. The ALS was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Contract No. DE-AC02-05CH11231. The authors acknowledge Diamond Light Source for time on Beamline I09 under Proposal SI127494. Inductively-coupled plasma mass spectrometry was performed in the Resnick Sustainability Institute's Water and Environment Lab at the California Institute of Technology.", "abstract": "Conventional cathodes for Li-ion batteries are layered transition-metal oxides that support Li\u207a intercalation charge-balanced by redox on the transition metals. Oxidation beyond one electron per transition metal can be achieved in Li-rich layered oxides by involving structural anions, which necessitates high voltages and complex charge compensation mechanisms convoluted by degradation reactions. We report a detailed structural and spectroscopic analysis of the multielectron material Li\u2082Ru_(0.3)Mn_(0.7)O\u2083, chosen due to its low Ru content. Ex situ and operando spectroscopic data over multiple cycles highlight the changing charge compensation mechanism. Notably, over half of the first-cycle capacity is attributed to O\u2082 gas evolution and reversible O redox is minimal. Instead, reduced Ru and Mn species are detected in the bulk and on the surface, which then increasingly contribute to charge compensation as more metal reduction occurs with cycling. Permanent structural changes linked to metal migration are observed with EXAFS and Raman analysis.", "date": "2023-01-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "8", "number": "1", "publisher": "American Chemical Society", "pagerange": "722-730", "id_number": "CaltechAUTHORS:20230206-9587900.28", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230206-9587900.28", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019381" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "David and Lucile Packard Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.2c02537", "pub_year": "2023", "author_list": "Zak, Joshua J.; Zuba, Mateusz; et al." }, { "id": "https://authors.library.caltech.edu/records/y5bvr-n4t30", "eprint_id": 118283, "eprint_status": "archive", "datestamp": "2023-08-22 18:44:52", "lastmod": "2023-10-24 23:16:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Watkins-Nicholas-B", "name": { "family": "Watkins", "given": "Nicholas B." }, "orcid": "0000-0001-7251-9387" }, { "id": "Wu-Yueshen", "name": { "family": "Wu", "given": "Yueshen" }, "orcid": "0000-0002-3784-0594" }, { "id": "Nie-Weixuan", "name": { "family": "Nie", "given": "Weixuan" }, "orcid": "0000-0003-2094-6840" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "In Situ Deposited Polyaromatic Layer Generates Robust Copper Catalyst for Selective Electrochemical CO\u2082 Reduction at Variable pH", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "Research was in part carried out at the Molecular Materials Research Center in the Beckman Institute; accordingly, we thank Bruce Brunschwig for the assistance with surface FT-IR measurements and Jake Evans for the assistance with XPS measurements. We also thank Aidan Fenwick for the assistance with AFM measurements and Matthias Richter for the assistance with XPS measurements. This material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. The Resnick Sustainability Institute at Caltech is also acknowledged for its support of enabling infrastructure and facilities.", "abstract": "Electrochemical reduction of CO\u2082 (CO\u2082R) by Cu metal holds promise to convert CO\u2082 to valuable C\u2082\u208a chemicals at scale using electricity and water but suffers from poor selectivity. Coating of metal electrodes with small organic molecules or polymers has been shown to effectively enhance catalytic performance but remains underexplored. Herein, facile modification of Cu surfaces by a polyaromatic layer was found to boost both selectivity and activity toward C\u2082\u208a products. Using phenyldiazonium or diphenyliodonium salts to graft an organic layer onto the surface of Cu foil electrodes resulted in up to 75% Faradaic efficiency (FE) for C\u2082\u208a at neutral pH. Modified electrodes have electrochemical active surface areas and proton diffusion coefficients similar to those of bare Cu. High CO\u2082R performance was maintained in a gas diffusion electrode, with a pH \u2248 1 electrolyte (1 M H\u2083PO\u2084, 1 M KCl; \u2212100 mA/cm\u00b2), producing 65% FE for C\u2082\u208a over 5 h, with no delamination.", "date": "2023-01-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "8", "number": "1", "publisher": "American Chemical Society", "pagerange": "189-195", "id_number": "CaltechAUTHORS:20221209-478595000.6", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221209-478595000.6", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.2c02002", "pub_year": "2023", "author_list": "Watkins, Nicholas B.; Wu, Yueshen; et al." }, { "id": "https://authors.library.caltech.edu/records/ype9w-psx16", "eprint_id": 118395, "eprint_status": "archive", "datestamp": "2023-08-22 18:41:57", "lastmod": "2025-04-26 02:37:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Phelan", "name": { "family": "Yu", "given": "Phelan" }, "orcid": "0000-0002-3715-9133" }, { "id": "Lopez-Adrian", "name": { "family": "Lopez", "given": "Adrian" }, "orcid": "0000-0002-7915-2597" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Hutzler-N-R", "name": { "family": "Hutzler", "given": "Nicholas R." }, "orcid": "0000-0002-5203-3635" } ] }, "title": "Multivalent optical cycling centers: towards control of polyatomics with multi-electron degrees of freedom", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry; General Physics and Astronomy", "note": "We thank Benjamin Augenbraun, Lan Cheng, Arian Jadbabaie, Anna Krylov, Nick Pilgram, and Pawe\u0142 W\u00f3jcik for insightful discussions and input. We also thank the anonymous referees for thoughtful feedback, which greatly improved the presentation of our results. P. Y. acknowledges support from the Eddleman Graduate Fellowship through the Institute for Quantum Information and Matter (IQIM), the Gordon and Betty Moore Foundation (7947), and the Alfred P. Sloan Foundation (G-2019-12502). A. L. acknowledges support from the C. S. Shastry Prize and the Caltech Associates SURF Fellowship. W. A. G. was supported by the Ferkel Chair. N. R. H. acknowledges support from the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), under Award No. DE-SC0019245. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.", "abstract": "Optical control of polyatomic molecules promises new opportunities in precision metrology and fundamental chemistry, as well as quantum information and many-body science. Contemporary experimental and theoretical efforts have mostly focused on cycling photons via excitation of a single electron localized to an alkaline earth (group 2)-like metal center. In this paper, we consider pathways towards optical cycling in polyatomic molecules with multi-electron degrees of freedom, which arise from two or more cycling electrons localized to p-block post-transition metal and metalloid (group 13, 14, and 15) centers. We characterize the electronic structure and rovibrational branching of several prototypical candidates using ab initio quantum chemical methods. Despite increased internal complexity and challenging design parameters, we find several molecules possessing quasi-closed photon cycling schemes with highly diagonal, visible and near-infrared transitions. Furthermore, we identify new heuristics for engineering optically controllable and laser-coolable polyatomic molecules with multi-electron cycling centers. Our results help elucidate the interplay between hybridization, repulsion, and ionicity in optically active species and provide new directions for using polyatomic molecules with complex electronic structure as a resource for quantum science and measurement.", "date": "2023-01-07", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "25", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "154-170", "id_number": "CaltechAUTHORS:20221216-550383000.6", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221216-550383000.6", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Institute for Quantum Information and Matter (IQIM)" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "7947" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "G-2019-12502" }, { "agency": "C. S. Shastry Prize" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "Ferkel Chair" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019245" }, { "agency": "Resnick Sustainability Institute" } ] }, "other_numbering_system": { "items": [ { "id": "1551", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "IQIM" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d2cp03545f", "pub_year": "2023", "author_list": "Yu, Phelan; Lopez, Adrian; et al." }, { "id": "https://authors.library.caltech.edu/records/kygs6-1fd61", "eprint_id": 118865, "eprint_status": "archive", "datestamp": "2023-08-22 18:35:15", "lastmod": "2023-10-24 23:31:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Biondi-Ettore", "name": { "family": "Biondi", "given": "Ettore" }, "orcid": "0000-0002-3305-0982" }, { "id": "Wang-Xin", "name": { "family": "Wang", "given": "Xin" } }, { "id": "Williams-Ethan-F", "name": { "family": "Williams", "given": "Ethan F." }, "orcid": "0000-0002-6471-4497" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" } ] }, "title": "Geolocalization of Large-Scale DAS Channels Using a GPS-Tracked Moving Vehicle", "ispublished": "pub", "full_text_status": "public", "keywords": "Geophysics", "note": "The authors would like to thank OptaSense for the support provided for this calibration experiment. In particular, the authors thank Martin Karrenbach, Victor Yartsev, and Vlad Bogdanov. The authors also thank the California Broadband Cooperative for providing access to the Digital 395 telecommunication fibers. The authors also thank James Atterholt and Jiaxuan Li for their insightful suggestions. Finally, the authors would like to thank Ariel Lellouch and two anonymous reviewers for their careful reading of their article and their many constructive comments and suggestions. This work is supported by National Science Foundation (NSF) Faculty Early Career Development Program (CAREER) Award Number 1848166, the Resnick Institute of Sustainability, and the Gordon and Betty Moore Foundation.", "abstract": "Geolocalization of distributed acoustic sensing (DAS) array channels represents a crucial step whenever the technology is deployed in the field. Commonly, the geolocalization is performed using point-wise active-source experiments, known as tap tests, conducted in the vicinity of the recording fiber. However, these controlled-source experiments are time consuming and greatly diminish the ability to promptly deploy such systems, especially for large-scale DAS experiments. We present a geolocalization methodology for DAS instrumentation that relies on seismic signals generated by a geotracked vehicle. We demonstrate the efficacy of our workflow by geolocating the channels of two DAS systems recording data on dark fibers stretching approximately 100\u00a0km within the Long Valley caldera area in eastern California. Our procedure permits the prompt calibration of DAS channel locations for seismic-related applications such as seismic hazard assessment, urban-noise monitoring, wavespeed inversion, and earthquake engineering. We share the developed set of codes along with a tutorial guiding users through the entire mapping process.", "date": "2023-01", "date_type": "published", "publication": "Seismological Research Letters", "volume": "94", "number": "1", "publisher": "Seismological Society of America", "pagerange": "318-330", "id_number": "CaltechAUTHORS:20230120-123072300.2", "issn": "0895-0695", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230120-123072300.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1848166" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" } ] }, "doi": "10.1785/0220220169", "pub_year": "2023", "author_list": "Biondi, Ettore; Wang, Xin; et al." }, { "id": "https://authors.library.caltech.edu/records/mgzme-mkf79", "eprint_id": 117603, "eprint_status": "archive", "datestamp": "2023-08-22 18:31:19", "lastmod": "2025-11-20 22:19:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saccone-Max-A", "name": { "family": "Saccone", "given": "Max A." }, "orcid": "0000-0003-3846-2908" }, { "id": "Gallivan-Rebecca-A", "name": { "family": "Gallivan", "given": "Rebecca A." }, "orcid": "0000-0001-6516-2180" }, { "id": "Narita-Kai", "name": { "family": "Narita", "given": "Kai" }, "orcid": "0000-0002-3867-8234" }, { "id": "Yee-Daryl-Wei-Liang", "name": { "family": "Yee", "given": "Daryl W." }, "orcid": "0000-0002-4114-6167" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Additive manufacturing of micro-architected metals via hydrogel infusion", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under award #DE-SC0016945. We thank Dr. Chi Ma for support and assistance with instruments in the Geological and Planetary Sciences Division Analytical Facility at Caltech, as well as Dr. Mingjie Xu and Dr. Xiaoqing Pan for assistance with TEM experiments at UC Irvine Materials Research Institute. M.A.S. acknowledges a graduate fellowship from the Resnick Sustainability Institute at Caltech. R.A.G. acknowledges the AI4SCIENCE graduate fellowship at Caltech. K.N. acknowledges a fellowship from the Masason Foundation. \n\nAuthor contributions. M.A.S, D.W.Y, and J.R.G. conceived of and designed the experiments. M.A.S and D.W.Y designed the photoresin, printing parameters, and swelling protocol and fabricated samples. M.A.S, D.W.Y, and K.N. performed the thermal treatments and FIB/SEM/EDS experiments. M.A.S performed the DSC, TGA, and XRD experiments. R.A.G. performed the nanoindentation and EBSD experiments, and prepared TEM samples. All authors analyzed data and discussed the findings. M.A.S, R.A.G, D.W.Y, and J.R.G. wrote the manuscript. All authors edited and approved the manuscript.\n\nCompeting interests. K.N. founded the company 3D Architech, LLC, which has an option and right to acquire an exclusive license to US Patent 11318435B2.", "abstract": "Metal additive manufacturing (AM) enables the production of high value and high performance components with applications from the aerospace to biomedical fields. Layer-by-layer fabrication circumvents the geometric limitations of traditional metalworking techniques, allowing topologically optimized parts to be made rapidly and efficiently. Existing AM techniques rely on thermally initiated melting or sintering for part shaping, a costly and material-limited process. We report an AM technique that produces metals and alloys with microscale resolution via vat photopolymerization (VP). 3D-architected hydrogels are infused with metal precursors, then calcined and reduced to convert the hydrogel scaffolds into miniaturized metal replicas. This approach represents a paradigm shift in VP; the material is selected only after the structure is fabricated. Unlike existing VP strategies, which incorporate target materials or precursors into the photoresin during printing, our method does not require re-optimization of resins and curing parameters for different materials, enabling quick iteration, compositional tuning, and the ability to fabricate multimaterials. We demonstrate AM of metals with critical dimensions of ~40 \u00b5m that are challenging to fabricate using conventional processes. Such hydrogel-derived metals have highly twinned microstructures and unusually high hardness, providing a pathway to create advanced metallic micromaterials.", "date": "2022-12-22", "date_type": "published", "publication": "Nature", "volume": "612", "number": "7941", "publisher": "Nature Publishing Group", "pagerange": "685-690", "id_number": "CaltechAUTHORS:20221026-429882000.2", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221026-429882000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0016945" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Amazon AI4Science Fellowship" }, { "agency": "Masason Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41586-022-05433-2", "pmcid": "PMC9713131", "pub_year": "2022", "author_list": "Saccone, Max A.; Gallivan, Rebecca A.; et al." }, { "id": "https://authors.library.caltech.edu/records/78zfx-aav07", "eprint_id": 119398, "eprint_status": "archive", "datestamp": "2023-08-22 18:24:55", "lastmod": "2025-11-20 18:15:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rehman-Faisal", "name": { "family": "Rehman", "given": "Faisal" }, "orcid": "0000-0002-2524-8681" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Musgrave-Charles-B-III", "name": { "family": "Musgrave", "given": "Charles B., III" }, "orcid": "0000-0002-3432-0817" }, { "id": "Tamtaji-Mohsen", "name": { "family": "Tamtaji", "given": "Mohsen" }, "orcid": "0000-0001-9118-5474" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Luo-Zhengtang", "name": { "family": "Luo", "given": "Zhengtang" }, "orcid": "0000-0002-5134-9240" } ] }, "title": "High-throughput screening to predict highly active dual-atom catalysts for electrocatalytic reduction of nitrate to ammonia", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; General Materials Science; Renewable Energy, Sustainability and the Environment", "note": "\u00a9 2022 Elsevier. \n\nZ.L. acknowledge supports by the RGC (16304421), the Innovation and Technology Commission (ITC-CNERC14SC01), Guangdong Science and Technology Department (Project#: 2020A0505090003), Research Fund of Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology (No. 2020B1212030010), IER Foundation (HT-JD-CXY-201907), and Shenzhen Special Fund for Central Guiding the Local Science and Technology Development (2021Szvup136). F.R. appreciates financial support from the Higher Education Commission (HEC) of Pakistan. WAG acknowledges support from the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. SK acknowledges support from the Resnick Sustainability Institute (RSI). \n\nData availability. Data will be made available on request. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\n

Supplemental Material - 1-s2.0-S2211285522009430-mmc1.docx

", "abstract": "Ammonia is an essential chemical owing to its importance in fertilizer production and other industrial applications. Electrocatalytic nitrate reduction to ammonia (NO\u2083RR) holds great promise for low-temperature ammonia production while simultaneously addressing nitrate-based environmental concerns. To provide the mechanistic understanding needed to design an effective electrocatalyst, we systematically investigated the catalytic performance of metal-based dual-atom catalysts (DACs) anchored on two-dimensional (2D) expanded phthalocyanine (Pc) for NO\u2083RR. We found that NO3RR can efficiently produce ammonia on Cr\u2082-Pc, V\u2082-Pc, Ti\u2082-Pc, and Mn\u2082-Pc surfaces with low limiting potentials of \u2212 0.02, \u2212 0.25, \u2212 0.34, and \u2212 0.41 VRHE, respectively. Moreover, using the free energy difference of *NO\u2083\u207b and *H as a descriptor, we found that the hydrogen evolution reaction is significantly suppressed on the DAC surface due to an ensemble effect in which the two metal atoms cooperate to selectively form ammonia. We performed high-throughput screening to develop an efficient metal-based DAC for NO\u2083\u207b reduction, followed by a mechanistic study to elucidate the NO\u2083RR pathway on the DAC. This work provides design information for advancing sustainable ammonia synthesis under ambient conditions.", "date": "2022-12-01", "date_type": "published", "publication": "Nano Energy", "volume": "103", "number": "Pt. B", "publisher": "Elsevier", "pagerange": "Art. No. 107866", "id_number": "CaltechAUTHORS:20230221-18908700.35", "issn": "2211-2855", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-18908700.35", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Research Grants Council of Hong Kong", "grant_number": "16304421" }, { "agency": "Innovation and Technology Commission (Hong Kong)", "grant_number": "ITC-CNERC14SC01" }, { "agency": "Guangdong Science and Technology Department", "grant_number": "2020A0505090003" }, { "agency": "Research Fund of Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology", "grant_number": "2020B1212030010" }, { "agency": "IER Foundation", "grant_number": "HT-JD-CXY-201907" }, { "agency": "Shenzhen Special Fund for Central Guiding the Local Science and Technology Development", "grant_number": "2021Szvup136" }, { "agency": "Higher Education Commission (Pakistan)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1016/j.nanoen.2022.107866", "primary_object": { "basename": "1-s2.0-S2211285522009430-mmc1.docx", "url": "https://authors.library.caltech.edu/records/78zfx-aav07/files/1-s2.0-S2211285522009430-mmc1.docx" }, "pub_year": "2022", "author_list": "Rehman, Faisal; Kwon, Soonho; et al." }, { "id": "https://authors.library.caltech.edu/records/b4hwp-ext86", "eprint_id": 117365, "eprint_status": "archive", "datestamp": "2023-08-22 18:23:40", "lastmod": "2025-11-21 01:15:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rehman-Faisal", "name": { "family": "Rehman", "given": "Faisal" } }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Musgrave-Charles-B-III", "name": { "family": "Musgrave", "given": "Charles B., III" }, "orcid": "0000-0002-3432-0817" }, { "id": "Tamtaji-Mohsen", "name": { "family": "Tamtaji", "given": "Mohsen" }, "orcid": "0000-0001-9118-5474" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Luo-Zhengtang", "name": { "family": "Luo", "given": "Zhengtang" }, "orcid": "0000-0002-5134-9240" } ] }, "title": "High-throughput screening to predict highly active dual-atom catalysts for electrocatalytic reduction of nitrate to ammonia", "ispublished": "pub", "full_text_status": "public", "keywords": "Dual-atom electrocatalyst; Nitrate reduction; Ammonia synthesis; In silico catalyst design; Electrocatalysis; Electrical and Electronic Engineering; General Materials Science; Renewable Energy, Sustainability and the Environment", "note": "Z.L. acknowledge supports by the RGC (16304421), the Innovation and Technology Commission (ITC-CNERC14SC01), Guangdong Science and Technology Department (Project#: 2020A0505090003), Research\nFund of Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology (No. 2020B1212030010), IER Foundation (HT-JD-CXY-201907), and Shenzhen Special Fund for Central Guiding the Local Science and Technology Development (2021Szvup136). F.R. appreciates financial support from the Higher Education Commission (HEC) of Pakistan. WAG acknowledges support from the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. SK acknowledges support from the Resnick Sustainability Institute (RSI).", "abstract": "Ammonia is an essential chemical owing to its importance in fertilizer production and other industrial applications. Electrocatalytic nitrate reduction to ammonia (NO\u2083RR) holds great promise for low-temperature ammonia production while simultaneously addressing nitrate-based environmental concerns. To provide the mechanistic understanding needed to design an effective electrocatalyst, we systematically investigated the catalytic performance of metal-based dual-atom catalysts (DACs) anchored on two-dimensional (2D) expanded phthalocyanine (Pc) for NO\u2083RR. We found that NO\u2083RR can efficiently produce ammonia on Cr\u2082-Pc, V\u2082-Pc, Ti\u2082-Pc, and Mn\u2082-Pc surfaces with low limiting potentials of \u2212 0.02, \u2212 0.25, \u2212 0.34, and \u2212 0.41 V_(RHE), respectively. Moreover, using the free energy difference of *NO\u2083\u207b and *H as a descriptor, we found that the hydrogen evolution reaction is significantly suppressed on the DAC surface due to an ensemble effect in which the two metal atoms cooperate to selectively form ammonia. We performed high-throughput screening to develop an efficient metal-based DAC for NO\u2083\u207b reduction, followed by a mechanistic study to elucidate the NO\u2083RR pathway on the DAC. This work provides design information for advancing sustainable ammonia synthesis under ambient conditions.", "date": "2022-12-01", "date_type": "published", "publication": "Nano Energy", "volume": "103", "number": "Part B", "publisher": "Elsevier", "pagerange": "Art. No. 107866", "id_number": "CaltechAUTHORS:20221011-984640000.3", "issn": "2211-2855", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221011-984640000.3", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Higher Education Commission (Pakistan)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Research Grants Council of Hong Kong", "grant_number": "16304421" }, { "agency": "Innovation and Technology Commission (Hong Kong)", "grant_number": "ITC-CNERC14SC01" }, { "agency": "Guangdong Science and Technology Department", "grant_number": "2020A0505090003" }, { "agency": "Research Fund of Guangdong-Hong Kong-Macao Joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology", "grant_number": "2020B1212030010" }, { "agency": "IER Foundation", "grant_number": "HT-JD-CXY-201907" }, { "agency": "Shenzhen Special Fund for Central Guiding the Local Science and Technology Development", "grant_number": "2021Szvup136" } ] }, "other_numbering_system": { "items": [ { "id": "1540", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1016/j.nanoen.2022.107866", "pub_year": "2022", "author_list": "Rehman, Faisal; Kwon, Soonho; et al." }, { "id": "https://authors.library.caltech.edu/records/m9gfv-cdk36", "eprint_id": 118486, "eprint_status": "archive", "datestamp": "2023-08-22 18:24:13", "lastmod": "2025-11-20 19:09:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oral-Elif", "name": { "family": "Oral", "given": "Elif" }, "orcid": "0000-0003-1081-5580" }, { "id": "Ampuero-J-P", "name": { "family": "Ampuero", "given": "Jean Paul" }, "orcid": "0000-0002-4827-7987" }, { "id": "Ruiz-Javier", "name": { "family": "Ruiz", "given": "Javier" } }, { "id": "Asimaki-D", "name": { "family": "Asimaki", "given": "Domniki" }, "orcid": "0000-0002-3008-8088" } ] }, "title": "A Method to Generate Initial Fault Stresses for Physics-Based Ground-Motion Prediction Consistent with Regional Seismicity", "ispublished": "pub", "full_text_status": "public", "keywords": "Geochemistry and Petrology; Geophysics", "note": "This work has been supported by the French government, through the Universit\u00e9 C\u00f4te d'Azur \"Joint, Excellent, and Dynamic Initiative\" (UCAJEDI) Investments in the Future project managed by the National Research Agency (ANR) with the Reference Number ANR\u201015\u2010IDEX\u201001, Southern California Earthquake Center (SCEC) Award 21010, and the California Institute of Technology. The computations presented here were conducted in the Thera cluster of Geoazur and the Resnick High Performance Computing Center\u2014a facility supported by Resnick Sustainability Institute at the California Institute of Technology. The authors acknowledge Caroline Ramel for IT support, and SCEC Dynamic Rupture Validation (DRV) benchmark participants and Yihe Huang for valuable discussions. The authors also acknowledge the constructive comments of Editor Luis Angel Dalguer, Franti\u0161ek Gallovi\u0107, and an anonymous reviewer that helped to improve the quality of this article.", "abstract": "Near\u2010field ground motion is the major blind spot of seismic hazard studies, mainly because of the challenges in accounting for source effects. Initial stress heterogeneity is an important component of physics\u2010based approaches to ground\u2010motion prediction that represents source effects through dynamic earthquake rupture modeling. We hypothesize that stress heterogeneity on a fault primarily originates from past background seismicity. We develop a new method to generate stochastic stress distributions as a superposition of residual stresses left by the previous ruptures that are consistent with regional distributions of earthquake size and hypocentral depth. We validate our method on M_w 7 earthquake models suitable for California by obtaining a satisfactory agreement with empirical earthquake scaling laws and ground\u2010motion prediction equations. To avoid the excessive seismic radiation produced by dynamic models with abrupt arrest at preset rupture borders, we achieve spontaneous rupture arrest by incorporating a growth of fracture energy as a function of hypocentral distance. Our analyses of rupture and ground motion reveal particular signatures of the initial stress heterogeneity: rupture can locally propagate at supershear speed near the highly stressed areas; the position of high\u2010stress and low\u2010stress areas due to initial stress heterogeneity determines how the peak ground\u2010motion amplitudes and polarization spatially vary along the fault, as low\u2010stress areas slow down the rupture and decrease stress drop. We also find that the medium stratification in the fault zone amplifies fault slip and consequent ground motion, which requires understanding the interaction between site effects and rupture dynamics. Our approach advances our understanding of the relations between dynamic features of earthquake ruptures and the statistics of regional seismicity, and our capability to integrate information about regional seismicity into near\u2010field ground\u2010motion prediction.", "date": "2022-12-01", "date_type": "published", "publication": "Bulletin of the Seismological Society of America", "volume": "112", "number": "6", "publisher": "Seismological Society of America", "pagerange": "2812-2827", "id_number": "CaltechAUTHORS:20221219-416589000.12", "issn": "0037-1106", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221219-416589000.12", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-15-IDEX-01" }, { "agency": "Southern California Earthquake Center (SCEC)", "grant_number": "21010" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1785/0120220064", "pub_year": "2022", "author_list": "Oral, Elif; Ampuero, Jean Paul; et al." }, { "id": "https://authors.library.caltech.edu/records/y03x8-77859", "eprint_id": 118752, "eprint_status": "archive", "datestamp": "2023-08-22 18:24:50", "lastmod": "2025-11-21 01:09:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Flamholz-Avi-I", "name": { "family": "Flamholz", "given": "Avi I." }, "orcid": "0000-0002-9278-5479" }, { "id": "Dugan-Eli", "name": { "family": "Dugan", "given": "Eli" }, "orcid": "0000-0003-2400-5511" }, { "id": "Panich-Justin", "name": { "family": "Panich", "given": "Justin" }, "orcid": "0000-0003-1283-4910" }, { "id": "Desmarais-John-J", "name": { "family": "Desmarais", "given": "John J." }, "orcid": "0000-0002-7739-2079" }, { "id": "Oltrogge-Luke-M", "name": { "family": "Oltrogge", "given": "Luke M." }, "orcid": "0000-0001-5716-9980" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Singer-Steven-W", "name": { "family": "Singer", "given": "Steven W." }, "orcid": "0000-0002-4229-8314" }, { "id": "Savage-David-F", "name": { "family": "Savage", "given": "David F." }, "orcid": "0000-0003-0042-2257" } ] }, "title": "Trajectories for the evolution of bacterial CO\u2082-concentrating mechanisms", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2022 the Author(s). Published by PNAS. This open access article is distributed under Creative Commons Attribution License 4.0 (CC BY). \n\nWe dedicate this paper to the memory of Danny Salah Tawfik (z\"l), a luminary to the scientific community and a dear friend and mentor to A.I.F. Danny's many studies of enzyme evolution taught us that evolutionary timescales are accessible in carefully designed lab-scale experiments and his active cultivation of relationships that transcend generational, professional, and cultural divides continues to inspire. We are also indebted to Arren Bar-Even (z\"l) for formative conversations guiding this work. Many thanks to Darcy McRose, Elad Noor, and Renee Wang for extensive comments on the manuscript and to Cecilia Blikstad, Julia Borden, Vahe Galstyan, Josh Goldford, Ron Milo, Robert Nichols, Naiya Phillips, Noam Prywes, and Gabe Salmon for helpful input. This research was supported in part by an NSF Graduate Research Fellowship (to A.I.F), NSF Grant No. PHY-1748958, the Gordon and Betty Moore Foundation Grant No. 2919.02, and the Kavli Foundation (to A.I.F), Schwartz/Reisman Collaborative Science Program (to W.W.F.), the US Department of Energy (DE-SC00016240 to D.F.S.), and Royal Dutch Shell (Energy and Biosciences Institute project CW163755 to D.F.S. and S.W.S.). \n\nAuthor contributions. A.I.F., E.D., W.W.F., and D.F.S. designed research; A.I.F., E.D., J.P., J.J.D., and L.M.O. performed research; S.W.S. contributed new reagents/analytic tools; A.I.F., E.D., J.P., J.J.D., L.M.O., W.W.F., and D.F.S. analyzed data; and A.I.F. and E.D. wrote the paper. \n\nThe authors declare no competing interest.\n\n

Published - pnas.202210539.pdf

Supplemental Material - pnas.2210539119.sapp.pdf

Supplemental Material - pnas.2210539119.sd01.xlsx

", "abstract": "Cyanobacteria rely on CO\u2082-concentrating mechanisms (CCMs) to grow in today's atmosphere (0.04% CO\u2082). These complex physiological adaptations require \u224815 genes to produce two types of protein complexes: inorganic carbon (Ci) transporters and 100+ nm carboxysome compartments that encapsulate rubisco with a carbonic anhydrase (CA) enzyme. Mutations disrupting any of these genes prohibit growth in ambient air. If any plausible ancestral form\u2014i.e., lacking a single gene\u2014cannot grow, how did the CCM evolve? Here, we test the hypothesis that evolution of the bacterial CCM was \"catalyzed\" by historically high CO\u2082 levels that decreased over geologic time. Using an E. coli reconstitution of a bacterial CCM, we constructed strains lacking one or more CCM components and evaluated their growth across CO\u2082 concentrations. We expected these experiments to demonstrate the importance of the carboxysome. Instead, we found that partial CCMs expressing CA or Ci uptake genes grew better than controls in intermediate CO\u2082 levels (\u22481%) and observed similar phenotypes in two autotrophic bacteria, Halothiobacillus neapolitanus and Cupriavidus necator. To understand how CA and Ci uptake improve growth, we model autotrophy as colimited by CO\u2082 and HCO\u2083\u207b, as both are required to produce biomass. Our experiments and model delineated a viable trajectory for CCM evolution where decreasing atmospheric CO\u2082 induces an HCO\u2083\u207b deficiency that is alleviated by acquisition of CA or Ci uptake, thereby enabling the emergence of a modern CCM. This work underscores the importance of considering physiology and environmental context when studying the evolution of biological complexity.", "date": "2022-12-01", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "119", "number": "49", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2210539119", "id_number": "CaltechAUTHORS:20230106-62570000.2", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230106-62570000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship" }, { "agency": "NSF", "grant_number": "PHY-1748958" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "2919.02" }, { "agency": "Kavli Foundation" }, { "agency": "Schwartz/Reisman Collaborative Science Program" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00016240" }, { "agency": "Royal Dutch Shell", "grant_number": "CW163755" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2210539119", "pmcid": "PMC9894237", "primary_object": { "basename": "pnas.202210539.pdf", "url": "https://authors.library.caltech.edu/records/y03x8-77859/files/pnas.202210539.pdf" }, "related_objects": [ { "basename": "pnas.2210539119.sapp.pdf", "url": "https://authors.library.caltech.edu/records/y03x8-77859/files/pnas.2210539119.sapp.pdf" }, { "basename": "pnas.2210539119.sd01.xlsx", "url": "https://authors.library.caltech.edu/records/y03x8-77859/files/pnas.2210539119.sd01.xlsx" } ], "pub_year": "2022", "author_list": "Flamholz, Avi I.; Dugan, Eli; et al." }, { "id": "https://authors.library.caltech.edu/records/tcf9s-6ab51", "eprint_id": 118086, "eprint_status": "archive", "datestamp": "2023-08-22 18:13:50", "lastmod": "2025-11-20 22:48:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "MacArdle-Siobh\u00e1n-G", "name": { "family": "MacArdle", "given": "Siobh\u00e1n G." }, "orcid": "0000-0001-7843-5977" }, { "id": "Rees-D-C", "name": { "family": "Rees", "given": "Douglas C." }, "orcid": "0000-0003-4073-1185" } ] }, "title": "Solvent Deuterium Isotope Effects of Substrate Reduction by Nitrogenase from Azotobacter vinelandii", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "The authors thank Dr. Nathan Dalleska for guidance in GC\u2013MS methods and data analysis, Dr. Jay Winkler for FTIR quantification and analysis of ethylene isotopologues, and Dr. David Vander Velde for guidance with NMR analysis. This project benefited from the use of instrumentation made available by the Resnick Sustainability Institute's Water and Environment Lab at the California Institute of Technology. FTIR spectra were recorded in the Beckman Institute Laser Resource Center at Caltech. The authors thank Dr. Trixia Buscagan, Dr. Rebeccah Warmack, Ailiena Maggiolo, and Dr. Stephanie Threatt for nitrogenase discussions. Discussions with Prof. Ralf Thauer on unpublished proton inventory studies with methyl coenzyme M reductase and Prof. James Howard (1942\u20132022) on nitrogenase, and enzyme mechanisms generally, are gratefully acknowledged. This work was generously funded by grants from the National Institute of Health (NIH GM045162) and the Howard Hughes Medical Institute to DCR and the Parsons Graduate Fellowship to SGM. This paper was adapted from Siobh\u00e1n MacArdle's PhD thesis from the California Institute of Technology.", "abstract": "The mechanism of nitrogenase, the enzyme responsible for biological nitrogen fixation, has been of great interest for understanding the catalytic strategy utilized to reduce dinitrogen to ammonia under ambient temperatures and pressures. The reduction mechanism of nitrogenase is generally envisioned as involving multiple cycles of electron and proton transfers, with the known substrates requiring at least two cycles. Solvent kinetic isotope effect experiments, in which changes of reaction rates or product distribution are measured upon enrichment of solvent with heavy atom isotopes, have been valuable for deciphering the mechanism of complex enzymatic reactions involving proton or hydrogen transfer. We report the distribution of ethylene, dihydrogen, and methane isotopologue products measured from nitrogenase-catalyzed reductions of acetylene, protons, and cyanide, respectively, performed in varying levels of deuterium enrichment of the solvent. As has been noted previously, the total rate of product formation by nitrogenase is largely insensitive to the presence of D\u2082O in the solvent. Nevertheless, the incorporation of H/D into products can be measured for these substrates that reflect solvent isotope effects on hydrogen atom transfers that are faster than the overall rate-determining step for nitrogenase. From these data, a minimal isotope effect is observed for acetylene reduction (1.4 \u00b1 0.05), while the isotope effects for hydrogen and methane evolution are significantly higher at 4.2 \u00b1 0.1 and 4.4 \u00b1 0.1, respectively. These results indicate that there are pronounced differences in the sensitivity to isotopic substitution of the hydrogen atom transfer steps associated with the reduction of these substrates by nitrogenase.", "date": "2022-11-23", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "144", "number": "46", "publisher": "American Chemical Society", "pagerange": "21125-21135", "id_number": "CaltechAUTHORS:20221128-494241100.48", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221128-494241100.48", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM045162" }, { "agency": "Howard Hughes Medical Institute (HHMI)" }, { "agency": "Ralph M. Parsons Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.2c07574", "pub_year": "2022", "author_list": "MacArdle, Siobh\u00e1n G. and Rees, Douglas C." }, { "id": "https://authors.library.caltech.edu/records/wh8mh-pqk33", "eprint_id": 118235, "eprint_status": "archive", "datestamp": "2023-08-22 18:12:27", "lastmod": "2025-11-21 02:47:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Debnath-Ramit", "name": { "family": "Debnath", "given": "Ramit" }, "orcid": "0000-0003-0727-5683" }, { "id": "Bardhan-Ronita", "name": { "family": "Bardhan", "given": "Ronita" }, "orcid": "0000-0001-5336-4084" }, { "id": "Shah-Darshil-U", "name": { "family": "Shah", "given": "Darshil U." } }, { "id": "Mohaddes-Kamiar", "name": { "family": "Mohaddes", "given": "Kamiar" }, "orcid": "0000-0002-2501-2062" }, { "id": "Ramage-Michael-H", "name": { "family": "Ramage", "given": "Michael H." }, "orcid": "0000-0003-2967-7683" }, { "id": "Alvarez-R-M", "name": { "family": "Alvarez", "given": "R. Michael" }, "orcid": "0000-0002-8113-4451" }, { "id": "Sovacool-Benjamin-K", "name": { "family": "Sovacool", "given": "Benjamin K." }, "orcid": "0000-0002-4794-9403" } ] }, "title": "Social media enables people-centric climate action in the hard-to-decarbonise building sector", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. \n\nRD acknowledges support from the Cambridge Zero and Quadrature Climate Foundation, Laudes Foundation, the Bill and Melinda Gates Foundation [OPP1144], Cambridge Judge Business School Small Grant (2020\u201321), the Keynes Fund 2021\u201322 [JHVH] and the Alan Turing Institute's Postdoctoral Enrichment Award [G116750]. Caltech's Resnick Sustainability Institute supports RMA's work. RB's work is supported by the UK Space Agency NSIP Award (2021\u201322). We would also like to thank Twitter for providing access to their APIs. A working paper version of this study can be found at Cambridge Working Paper in Economics 2202. \n\nData availability. The datasets analysed during the current study are available in the Open Science Framework repository https://doi.org/10.17605/OSF.IO/QC453. The user identifiers are anonymized as per Twitter's developers policy and GDPR rules https://gdpr.twitter.com/see here. \n\nEthics approval. This research was reviewed by the Institutional Review Board at the Judge Business School, University of Cambridge (20-064) and at the California Institute of Technology (21-1169). Twitter was informed about this research during the v2API request.\n\n

Published - 41598_2022_Article_23624.pdf

Supplemental Material - 41598_2022_23624_MOESM1_ESM.pdf

", "abstract": "The building and construction sector accounts for around 39% of global carbon dioxide emissions and remains a hard-to-abate sector. We use a data-driven analysis of global high-level climate action on emissions reduction in the building sector using 256,717 English-language tweets across a 13-year time frame (2009\u20132021). Using natural language processing and network analysis, we show that public sentiments and emotions on social media are reactive to these climate policy actions. Between 2009\u20132012, discussions around green building-led emission reduction efforts were highly influential in shaping the online public perceptions of climate action. From 2013 to 2016, communication around low-carbon construction and energy efficiency significantly influenced the online narrative. More significant interactions on net-zero transition, climate tech, circular economy, mass timber housing and climate justice in 2017\u20132021 shaped the online climate action discourse. We find positive sentiments are more prominent and recurrent and comprise a larger share of the social media conversation. However, we also see a rise in negative sentiment by 30\u201340% following popular policy events like the IPCC report launches, the Paris Agreement and the EU Green Deal. With greater online engagement and information diffusion, social and environmental justice topics emerge in the online discourse. Continuing such shifts in online climate discourse is pivotal to a more just and people-centric transition in such hard-to-decarbonise sectors.", "date": "2022-11-17", "date_type": "published", "publication": "Scientific Reports", "volume": "12", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 19017", "id_number": "CaltechAUTHORS:20221205-666301600.8", "issn": "2045-2322", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221205-666301600.8", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Cambridge Zero" }, { "agency": "Quadrature Climate Foundation" }, { "agency": "Laudes Foundation" }, { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1144" }, { "agency": "University of Cambridge" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Alan Turing Institute", "grant_number": "G116750" }, { "agency": "United Kingdom Space Agency (UKSA)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41598-022-23624-9", "pmcid": "PMC9671910", "primary_object": { "basename": "41598_2022_23624_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/wh8mh-pqk33/files/41598_2022_23624_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41598_2022_Article_23624.pdf", "url": "https://authors.library.caltech.edu/records/wh8mh-pqk33/files/41598_2022_Article_23624.pdf" } ], "pub_year": "2022", "author_list": "Debnath, Ramit; Bardhan, Ronita; et al." }, { "id": "https://authors.library.caltech.edu/records/42w1d-gxj13", "eprint_id": 118087, "eprint_status": "archive", "datestamp": "2023-08-22 18:11:59", "lastmod": "2025-11-20 23:44:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kazmierczak-Nathanael-P", "name": { "family": "Kazmierczak", "given": "Nathanael P." }, "orcid": "0000-0002-7822-6769" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Illuminating Ligand Field Contributions to Molecular Qubit Spin Relaxation via T\u2081 Anisotropy", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "The authors would like to acknowledge Paul H. Oyala for assistance with EPR data collection, Ruben Mirzoyan and Jinsoo Park for discussions about spin relaxation theory, Ryan D. Ribson for providing the CuPc and VOPc samples, and Alexandra T. Barth for providing the [Cu(mnt)2]2\u2013 sample. N.P.K. acknowledges support by the Hertz Fellowship and the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1745301. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. Financial support from the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Atomic, Molecular, and Optical Sciences program (DE-SC0022920), as well as Caltech and the Dow Next Generation Educator Fund, is gratefully acknowledged.", "abstract": "Electron spin relaxation in paramagnetic transition metal complexes constitutes a key limitation on the growth of molecular quantum information science. However, there exist very few experimental observables for probing spin relaxation mechanisms, leading to a proliferation of inconsistent theoretical models. Here we demonstrate that spin relaxation anisotropy in pulsed electron paramagnetic resonance is a powerful spectroscopic probe for molecular spin dynamics across a library of highly coherent Cu(II) and V(IV) complexes. Neither the static spin Hamiltonian anisotropy nor contemporary computational models of spin relaxation are able to account for the experimental T1 anisotropy. Through analysis of the spin\u2013orbit coupled wave functions, we derive an analytical theory for the T\u2081 anisotropy that accurately reproduces the average experimental anisotropy of 2.5. Furthermore, compound-by-compound deviations from the average anisotropy provide a promising approach for observing specific ligand field and vibronic excited state coupling effects on spin relaxation. Finally, we present a simple density functional theory workflow for computationally predicting T\u2081 anisotropy. Analysis of spin relaxation anisotropy leads to deeper fundamental understanding of spin\u2013phonon coupling and relaxation mechanisms, promising to complement temperature-dependent relaxation rates as a key metric for understanding molecular spin qubits.", "date": "2022-11-16", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "144", "number": "45", "publisher": "American Chemical Society", "pagerange": "20804-20814", "id_number": "CaltechAUTHORS:20221128-494241100.49", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221128-494241100.49", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Fannie and John Hertz Foundation" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022920" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.2c08729", "pub_year": "2022", "author_list": "Kazmierczak, Nathanael P. and Hadt, Ryan G." }, { "id": "https://authors.library.caltech.edu/records/fzkf9-6mp37", "eprint_id": 118237, "eprint_status": "archive", "datestamp": "2023-08-22 18:09:43", "lastmod": "2025-11-20 22:10:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Aati-Saif", "name": { "family": "Aati", "given": "Saif" }, "orcid": "0000-0003-1087-832X" }, { "id": "Avouac-J-P", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" }, { "id": "Rupnik-Ewelina", "name": { "family": "Rupnik", "given": "Ewelina" }, "orcid": "0000-0002-7229-5501" }, { "id": "Deseilligny-Marc-Pierrot", "name": { "family": "Deseilligny", "given": "Marc-Pierrot" } } ] }, "title": "Potential and Limitation of PlanetScope Images for 2-D and 3-D Earth Surface Monitoring With Example of Applications to Glaciers and Earthquakes", "ispublished": "pub", "full_text_status": "public", "keywords": "General Earth and Planetary Sciences; Electrical and Electronic Engineering", "note": "This work was supported in part by the Resnick Sustainability Institute, National Aeronautics and Space Administration (NASA), under Grant 80NSSC20K0492, and in part by the Southern California Earthquake Center (SCEC); SCEC is funded in part by the NSF Cooperative Agreement EAR-1600087 and in part by the USGS Cooperative Agreement G17AC00047.\n\nThe authors would like to thank Kelsey Jordahl, Antonio Martos, and their colleagues at Planet for the information on sensors specification and data acquisition modes and helpful discussions. They also thank Shashank Bhushan and David Shean for helpful discussions. Supplementary data to this article can be found online: Saif Aati, \"Potential and Limitation of PlanetScope Images for 2-D and 3-D Earth Surface Monitoring With Example of Applications to Glaciers and Earthquakes\u2014Supporting Document,\" September 2022, doi: 10.5281/zenodo.7090760.", "abstract": "The Planet PlanetScope (PS) CubeSat constellation acquires high-resolution optical images that cover the entire surface of the Earth daily, enabling an unprecedented capability to monitor the Earth's surface changes. However, our analysis reveals artifacts of the geometry of PS images related to the imaging system and processing issues, limiting the usability of these data for various Earth science applications, including the monitoring of glaciers, dune motion, or the measurement of ground deformation due to earthquakes and landslides. Here, we analyze these artifacts and propose ways to remediate them. We use two examples to evaluate the data and assess the performance of our proposed approaches. The first is the ground deformation caused by the 2019 Ridgecrest earthquake sequence, California, USA, and the second is the 2018\u20132019 surge of the Shisper glacier in the Karakorum. Using an image correlation technique, we show that PS images exhibit several geometric artifacts, such as scene-to-scene misregistration, inconsistence geolocation accuracy between spectral bands, and topographic artifacts. Altogether, these artifacts make a quantitative analysis of ground displacement difficult and inaccurate. We present a method that remediates most of these geometric artifacts. In addition, we propose a framework for selecting the most appropriate images and a procedure for refining the rational function model (RFM) of unrectified images to monitor surface displacements and topography changes in 3-D. These tools should enhance the use of PS images for Earth science applications.", "date": "2022-11-07", "date_type": "published", "publication": "IEEE Transactions on Geoscience and Remote Sensing", "volume": "60", "publisher": "IEEE", "pagerange": "Art. No. 4512919", "id_number": "CaltechAUTHORS:20221205-666301600.12", "issn": "0196-2892", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221205-666301600.12", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA", "grant_number": "80NSSC20K0492" }, { "agency": "Southern California Earthquake Center (SCEC)" }, { "agency": "NSF", "grant_number": "EAR-1600087" }, { "agency": "USGS", "grant_number": "G17AC00047" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" } ] }, "doi": "10.1109/tgrs.2022.3215821", "pub_year": "2022", "author_list": "Aati, Saif; Avouac, Jean-Philippe; et al." }, { "id": "https://authors.library.caltech.edu/records/wpx99-wbr80", "eprint_id": 118050, "eprint_status": "archive", "datestamp": "2023-08-22 18:08:58", "lastmod": "2025-11-20 23:23:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Derosa-Joseph", "name": { "family": "Derosa", "given": "Joseph" }, "orcid": "0000-0001-8672-4875" }, { "id": "Garrido-Barros-Pablo", "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Li-Mengdi", "name": { "family": "Li", "given": "Mengdi" }, "orcid": "0000-0002-6198-8396" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Use of a PCET Mediator Enables a Ni-HER Electrocatalyst to Act as a Hydride Delivery Agent", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "We thank the Dow Next Generation Educator Funds and Instrumentation Grants for their support of the NMR facility at Caltech. We also thank the Resnick Water and Environment Laboratory at Caltech for the use of their instrumentation. The authors are grateful to the Department of Energy Basic Energy Sciences for support via grant no. DE-SC0019136 and also to the American Chemical Society Petroleum Research Fund (PRF# 61951-ND3). J.D. thanks the Arnold and Mabel Beckman Foundation for a postdoctoral fellowship, P.G.-B. thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship, and J.C.P. is grateful to the Resnick Sustainability Institute.", "abstract": "The generation of metal hydride intermediates during reductive electrocatalysis in the presence of acid most commonly leads to the hydrogen evolution reaction (HER). Redirecting the reactivity profile of such hydride intermediates toward the reduction of unsaturated substrates is an exciting opportunity in catalysis but presents a challenge in terms of catalyst selectivity. In this study, we demonstrate that a prototypical phosphine-supported Ni-HER catalyst can be repurposed toward the electrocatalytic reduction of a model substrate, methyl phenylpropiolate, via hydride transfer from a Ni^(\u026a\u026a)\u2013H when interfaced with a metallocene-derived proton-coupled electron transfer (PCET) mediator. Key to success is generation of the Ni^(\u026a\u026a)\u2013H at a potential pinned to that of the PCET mediator which is appreciably anodic of the onset of HER. Electrochemical, spectroscopic, and theoretical data point to a working mechanism where a PCET step from the metallocene-derived mediator to Ni^(\u026a\u026a) generates Ni^(\u026a\u026a\u026a)\u2013H and is rate-determining; the latter Ni^(\u026a\u026a\u026a)\u2013H is then readily reduced to a Ni^(\u026a\u026a)\u2013H, which is competent for substrate reduction. Additional studies show that this tandem PCET-mediated hydride generation can afford high stereoselectivity (e.g., >20:1 Z/E using a phosphine-cobalt precatalyst with ethyl 2\u2013heptynoate) and can also be used for the reduction of \u03b1,\u03b2-unsaturated ketones.", "date": "2022-11-02", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "144", "number": "43", "publisher": "American Chemical Society", "pagerange": "20118-20125", "id_number": "CaltechAUTHORS:20221128-494241100.4", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221128-494241100.4", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019136" }, { "agency": "Ram\u00f3n Areces Foundation" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "American Chemical Society Petroleum Research Fund", "grant_number": "61951-ND3" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.2c09786", "pub_year": "2022", "author_list": "Derosa, Joseph; Garrido-Barros, Pablo; et al." }, { "id": "https://authors.library.caltech.edu/records/nz3s3-3rd55", "eprint_status": "archive", "datestamp": "2025-03-13 17:33:27", "lastmod": "2025-11-20 17:55:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "name": { "family": "Wei", "given": "Jing" }, "orcid": "0000-0002-8803-7056" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "name": { "family": "Shang", "given": "Quanbiao" } }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Yin-Yi", "name": { "family": "Yin", "given": "Yi" }, "orcid": "0000-0003-4750-4997" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "name": { "family": "Li", "given": "Zhanqing" }, "orcid": "0000-0001-6737-382X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Marked Impacts of Pollution Mitigation on Crop Yields in China", "ispublished": "pub", "full_text_status": "public", "keywords": "pollution; climate change; crop yield; statistical model; policy", "note": "

© 2022. The Authors. Earth's Future published by Wiley Periodicals LLC on behalf of American Geophysical Union.

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This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

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Y.W. acknowledges the support of NSF (AGS-2103714). L.H. acknowledges the fellowship supported by the Resnick Sustainability Institute at California Institute of Technology. Y.W., J.L., C.F., J.H.J. and Y.L.Y. acknowledge the support of the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. J.W. and Z.L. acknowledge the NASA Applied Science program (number: 80NSSC21K1980). We thank Drs. Xu Yue and Chao Liu for helpful discussions. All correspondence and requests for materials in this paper should be addressed to Y.W (yuanwang@purdue.edu).

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Conceptualization: Yuan Wang. Data curation: Liyin He, Jing Wei. Formal analysis: Liyin He, Jing Wei, Yuan Wang, Quanbiao Shang, Junjie Liu, Yi Yin, Christian Frankenberg, Zhanqing Li, Yuk L. Yung. Investigation: Liyin He, Jing Wei, Yuan Wang Methodology: Liyin He, Yuan Wang. Project Administration: Yuan Wang. Resources: Liyin He, Jing Wei, Yuan Wang. Supervision: Yuan Wang. Validation: Yuan Wang. Visualization: Liyin He, Yuan Wang. Writing – original draft: Liyin He, Yuan Wang. Writing – review & editing: Liyin He, Jing Wei, Yuan Wang, Quanbiao Shang, Junjie Liu, Yi Yin, Christian Frankenberg, Jonathan H. Jiang, Zhanqing Li, Yuk L. Yung.

\n\n

The monthly temperature and precipitation products used in this study are publicly available at Copernicus Climate Change Service (https://cds.climate.copernicus.eu/cdsapp%23%21/dataset/reanalysis%2Dera5%2Dsingle%2Dlevels%2Dmonthly%2Dmeans%3Ftab%3Dform). The monthly aerosol optical depth (AOD) reanalysis product is available at Goddard Earth Sciences Data and Information Services Center (https://disc.gsfc.nasa.gov/datasets/M2TMNXAER_5.12.4/summary). The monthly surface ozone data set is from the ChinaHighAirPollutants (CHAP) data set (https://zenodo.org/record/5765588#.Yo60MJPMK3I). The Spatial Production Allocation Model crop spatial distribution is available at https://s3.amazonaws.com/mapspam/2010/v2.0/geotiff/spam2010v2r0_global_phys_area.geotiff.zip. The annual province-level crop statistics are from National Bureau of Statistics of China (NBSC) (https://data.stats.gov.cn/english/adv.htm?cn=C01). NBCS requires registration to obtain a free account, then annual statistics report can be found in the search bar and downloaded as CSV files. The processed data used in this study and the code of our statistical models can be downloaded from https://doi.org/10.5281/zenodo.7232790.

\n\n

Supporting Information S1 (DOCX)

", "abstract": "
\n

Plant growth and crop harvest are impacted by both climate change and air pollution. However, their relative importance in crop yields remains elusive, especially in heavily polluted regions. Here we develop crop yield prediction models, based on a large volume of historical crop data, as well as climate and pollution records in China since 1980. A long-term surface ozone concentration data set is developed from a machine-learning model and various observations. An assessment of four climate and pollution factors reveals the critical role of particulate and ozone pollution in regulating interannual variations of crop yields in China. During 2010–2018, we find that the particulate pollution mitigation outweighs the negative impacts of concurrent climate change, resulting in 0.5%–1.9% net yield increases nationwide, despite of the ozone increases in the North China Plain. Looking to the future, the impacts of climate change, particularly from surface temperature increase, will dominate over pollution factors and profoundly reduce future maize and rice yields by 0.6 to 2.8% 10 yr−1 by 2050. Our findings call for attention on the threat to future global food security from the absence of pollution mitigation and the persistence of global warming.

\n
", "date": "2022-11", "date_type": "published", "publication": "Earth's Future", "volume": "10", "number": "11", "publisher": "American Geophysical Union", "pagerange": "e2022EF002936", "issn": "2328-4277", "official_url": "https://authors.library.caltech.edu/records/nz3s3-3rd55", "funders": { "items": [ { "grant_number": "AGS-2103714" }, {}, {}, { "grant_number": "80NSSC21K1980" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2022ef002936", "primary_object": { "basename": "Earth s Future - 2022 - He - Marked Impacts of Pollution Mitigation on Crop Yields in China.pdf", "url": "https://authors.library.caltech.edu/records/nz3s3-3rd55/files/Earth s Future - 2022 - He - Marked Impacts of Pollution Mitigation on Crop Yields in China.pdf" }, "related_objects": [ { "basename": "2022ef002936-sup-0001-supporting information si-s01.docx", "url": "https://authors.library.caltech.edu/records/nz3s3-3rd55/files/2022ef002936-sup-0001-supporting information si-s01.docx" } ], "pub_year": "2022", "author_list": "He, Liyin; Wei, Jing; et al." }, { "id": "https://authors.library.caltech.edu/records/tmnrt-9y586", "eprint_id": 117352, "eprint_status": "archive", "datestamp": "2023-08-22 18:02:34", "lastmod": "2025-11-21 03:51:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Christianson-Nicolas-H", "name": { "family": "Christianson", "given": "Nicolas" }, "orcid": "0000-0001-8330-8964" }, { "id": "Werner-Lucien-D", "name": { "family": "Werner", "given": "Lucien" } }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" }, "orcid": "0000-0002-5923-0199" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Dispatch-aware planning for feasible power system operation", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; Energy Engineering and Power Technology", "note": "The authors are supported by the NSF Graduate Research Fellowship, USA (DGE-1745301), Resnick Sustainability Institute Graduate Fellowship, USA, Pimco Graduate Fellowship in Data Science, USA, NSF, USA grants CNS-2106403, NGSDI-2105648, ECCS 1931662, and CPS ECCS 1932611, and Amazon AWS, USA.", "abstract": "Maintaining stable energy production with increasing penetration of variable renewable energy requires sufficient flexible generation resources and dispatch algorithms that accommodate renewables' uncertainty. In this work, we study the feasibility properties of real-time economic dispatch (RTED) algorithms and establish fundamental limits on their performance. We propose a joint methodology for resource procurement and online economic dispatch with guaranteed feasibility. Our algorithm, Feasible Fixed Horizon Control (FFHC) is a regularized form of Receding Horizon Control (RHC) that balances exploitation of good near-term demand predictions with feasibility requirements. Empirical evaluation of FFHC in comparison to the standard RHC on realistic load profiles highlights that FFHC achieves near-optimal performance while ensuring feasibility in high-ramp scenarios where RHC becomes infeasible.", "date": "2022-11", "date_type": "published", "publication": "Electric Power Systems Research", "volume": "212", "publisher": "Elsevier", "pagerange": "Art. No. 108597", "id_number": "CaltechAUTHORS:20221011-128968500.6", "issn": "0378-7796", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221011-128968500.6", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-2106403" }, { "agency": "NSF", "grant_number": "ECCS-1932611" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "NSF", "grant_number": "CNS-2105648" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Amazon Web Services" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.epsr.2022.108597", "pub_year": "2022", "author_list": "Christianson, Nicolas; Werner, Lucien; et al." }, { "id": "https://authors.library.caltech.edu/records/90e1h-5xs38", "eprint_id": 117801, "eprint_status": "archive", "datestamp": "2023-08-22 18:00:01", "lastmod": "2025-11-20 18:20:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "A comparison between the one- and two-step spin-orbit coupling approaches based on the ab initio density matrix renormalization group", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry; General Physics and Astronomy", "note": "This work was supported by the U.S. Department of Energy, Office of Science, via Award No. DE-SC0019390. H.Z. thanks Zhi-Hao Cui for useful discussions on mean-field calculation and high performance computing strategies and Xubo Wang for discussions on relativistic Hamiltonians and spin\u2013orbit effective core potentials. The computations presented in this work were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology.", "abstract": "The efficient and reliable treatment of both spin\u2013orbit coupling (SOC) and electron correlation is essential for understanding f-element chemistry. We analyze two approaches to the problem: the one-step approach, where both effects are treated simultaneously, and the two-step state interaction approach. We report an implementation of the ab initio density matrix renormalization group with a one-step treatment of the SOC effect, which can be compared to prior two-step treatments on an equal footing. Using a dysprosium octahedral complex and bridged dimer as benchmark systems, we identify characteristics of problems where the one-step approach is beneficial for obtaining the low-energy spectrum.", "date": "2022-10-28", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "157", "number": "16", "publisher": "American Institute of Physics", "pagerange": "Art. No. 164108", "id_number": "CaltechAUTHORS:20221109-552977300.2", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221109-552977300.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019390" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/5.0107805", "pub_year": "2022", "author_list": "Zhai, Huanchen and Chan, Garnet Kin-Lic" }, { "id": "https://authors.library.caltech.edu/records/ety0z-3tz63", "eprint_id": 118301, "eprint_status": "archive", "datestamp": "2023-08-22 17:59:46", "lastmod": "2025-11-21 00:47:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johansen-Christian-M", "name": { "family": "Johansen", "given": "Christian M." }, "orcid": "0000-0003-0066-4424" }, { "id": "Boyd-Emily-A", "name": { "family": "Boyd", "given": "Emily A." }, "orcid": "0000-0003-0150-5396" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Catalytic transfer hydrogenation of N\u2082 to NH\u2083 via a photoredox catalysis strategy", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY). \n\nWe thank the Dow Next Generation Educator Fund and Instrumentation Grants for support of the NMR facility at Caltech. The Beckman Institute Laser Resource Center and J. R. Winkler are acknowledged for providing support with steady-state luminescence experiments. We also thank the Resnick Sustainability Institute at Caltech for enabling facilities, including its Water and Environment Laboratory (WEL). \n\nThis work was supported by the National Institutes of Health (R01 GM-075757). E.A.B. acknowledges the support of the National Science Foundation for a Graduate Research Fellowship under grant no. DGE-1745301. \n\nAuthor contributions: Conceptualization: C.M.J. and J.C.P. Methodology: C.M.J., E.A.B., and J.C.P. Investigation: C.M.J. and E.A.B. Visualization: C.M.J., E.A.B., and J.C.P. Funding acquisition: E.A.B. and J.C.P. Project administration: J.C.P. Supervision: J.C.P. Writing\u2014original draft: C.M.J. and E.A.B. Writing\u2014review and editing: C.M.J., E.A.B., and J.C.P. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. \n\nThe authors declare that they have no competing interests.\n\n

Published - sciadv.ade3510.pdf

Supplemental Material - sciadv.ade3510_sm.pdf

", "abstract": "Inspired by momentum in applications of reductive photoredox catalysis to organic synthesis, photodriven transfer hydrogenations toward deep (>2 e\u207b) reductions of small molecules are attractive compared to using harsh chemical reagents. Noteworthy in this context is the nitrogen reduction reaction (N\u2082RR), where a synthetic photocatalyst system had yet to be developed. Noting that a reduced Hantzsch ester (HEH\u2082) and related organic structures can behave as 2 e\u207b/2 H\u207a photoreductants, we show here that, when partnered with a suitable catalyst (Mo) under blue light irradiation, HEH\u2082 facilitates delivery of successive H\u2082 equivalents for the 6 e\u207b/6 H\u207a catalytic reduction of N\u2082 to NH\u2083; this catalysis is enhanced by addition of a photoredox catalyst (Ir). Reductions of additional substrates (nitrate and acetylene) are also described.", "date": "2022-10-26", "date_type": "published", "publication": "Science Advances", "volume": "8", "number": "43", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eade3510", "id_number": "CaltechAUTHORS:20221212-795726500.3", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221212-795726500.3", "funders": { "items": [ { "agency": "Dow Next Generation Educator Fund" }, { "agency": "NIH", "grant_number": "R01 GM-075757" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.ade3510", "pmcid": "PMC9604530", "primary_object": { "basename": "sciadv.ade3510.pdf", "url": "https://authors.library.caltech.edu/records/ety0z-3tz63/files/sciadv.ade3510.pdf" }, "related_objects": [ { "basename": "sciadv.ade3510_sm.pdf", "url": "https://authors.library.caltech.edu/records/ety0z-3tz63/files/sciadv.ade3510_sm.pdf" } ], "pub_year": "2022", "author_list": "Johansen, Christian M.; Boyd, Emily A.; et al." }, { "id": "https://authors.library.caltech.edu/records/vhmw7-pjt41", "eprint_id": 117027, "eprint_status": "archive", "datestamp": "2023-08-22 17:45:18", "lastmod": "2025-11-21 00:11:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Larsson-Henrik-R", "name": { "family": "Larsson", "given": "Henrik R." }, "orcid": "0000-0002-9417-1518" }, { "id": "Schr\u00f6der-Markus", "name": { "family": "Schr\u00f6der", "given": "Markus" }, "orcid": "0000-0002-8032-9791" }, { "id": "Beckmann-Richard", "name": { "family": "Beckmann", "given": "Richard" } }, { "id": "Brieuc-Fabien", "name": { "family": "Brieuc", "given": "Fabien" } }, { "id": "Schran-Christoph", "name": { "family": "Schran", "given": "Christoph" }, "orcid": "0000-0003-4595-5073" }, { "id": "Marx-Domink", "name": { "family": "Marx", "given": "Dominik" } }, { "id": "Vendrell-Oriol", "name": { "family": "Vendrell", "given": "Oriol" }, "orcid": "0000-0003-4629-414X" } ] }, "title": "State-resolved infrared spectrum of the protonated water dimer: revisiting the characteristic proton transfer doublet peak", "ispublished": "pub", "full_text_status": "public", "keywords": "General Chemistry", "note": "\u00a9 2022 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. \n\nThe authors thank Professor Joel Bowman for having made their potential energy surface available. HRL acknowledges support from the University of California Merced start-up funding during the last part of this work. HRL acknowledges support from a postdoctoral fellowship from the German Research Foundation (DFG) via grant LA 4442/1-1 during the first part of this work. HRL acknowledges computational time both on the Pinnacles cluster at UC Merced (supported by NSF OAC-2019144) and at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. The Bochum work has been funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy \u2013 EXC 2033 \u2013 390677874 \u2013 RESOLV as well as by the individual DFG grant MA 1547/19 to DM and supported by the \"Center for Solvation Science ZEMOS\" funded by the German Federal Ministry of Education and Research and by the Ministry of Culture and Research of North Rhine-Westphalia. RB acknowledges funding from the Studienstiftung des deutschen Volkes and CS acknowledges partial financial support from the Alexander von Humboldt-Stiftung. MS and OV thank the High Performance Computing Center in Stuttgart (HLRS) under the grant number HDQM_MCT as well as the bwHPC project of the state of Baden-W\u00fcrttemberg under grant number bw18K011 for providing computational resources. \n\nAll publication charges for this article have been paid for by the Royal Society of Chemistry. \n\nAuthor contributions. H. R. L. and O. V. conceived the study; H. R. L. designed the study, developed the TTNS methodology and performed and analyzed the TTNS simulations; M. S. and O. V. performed the MCCPD fits and additional ML-MCTDH simulations; R. B., F. B., C. S., and D. M. created the interface for the BBSM PES, provided samples for the MCCPD procedure, and performed benchmarks for DMC configurations provided by M. S.; H. R. L. drafted the manuscript; all authors contributed to discussing the results and editing the manuscript. \n\nData availability. Further data is available from the authors upon reasonable request. \n\nThere are no conflicts to declare.\n\n

Published - d2sc03189b.pdf

Supplemental Material - d2sc03189b1.pdf

", "abstract": "The infrared (IR) spectra of protonated water clusters encode precise information on the dynamics and structure of the hydrated proton. However, the strong anharmonic coupling and quantum effects of these elusive species remain puzzling up to the present day. Here, we report unequivocal evidence that the interplay between the proton transfer and the water wagging motions in the protonated water dimer (Zundel ion) giving rise to the characteristic doublet peak is both more complex and more sensitive to subtle energetic changes than previously thought. In particular, hitherto overlooked low-intensity satellite peaks in the experimental spectrum are now unveiled and mechanistically assigned. Our findings rely on the comparison of IR spectra obtained using two highly accurate potential energy surfaces in conjunction with highly accurate state-resolved quantum simulations. We demonstrate that these high-accuracy simulations are important for providing definite assignments of the complex IR signals of fluxional molecules.", "date": "2022-10-25", "date_type": "published", "publication": "Chemical Science", "volume": "13", "number": "37", "publisher": "Royal Society of Chemistry", "pagerange": "11119-11125", "id_number": "CaltechAUTHORS:20220916-665970000", "issn": "2041-6520", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220916-665970000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Studienstiftung des Deutschen Volkes" }, { "agency": "Alexander von Humboldt Foundation" }, { "agency": "NSF", "grant_number": "OAC-2019144" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "LA 4442/1-1" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "390677874" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "MA 1547/19" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of California, Merced" }, { "agency": "Royal Society of Chemistry" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d2sc03189b", "pmcid": "PMC9517273", "primary_object": { "basename": "d2sc03189b1.pdf", "url": "https://authors.library.caltech.edu/records/vhmw7-pjt41/files/d2sc03189b1.pdf" }, "related_objects": [ { "basename": "d2sc03189b.pdf", "url": "https://authors.library.caltech.edu/records/vhmw7-pjt41/files/d2sc03189b.pdf" } ], "pub_year": "2022", "author_list": "Larsson, Henrik R.; Schr\u00f6der, Markus; et al." }, { "id": "https://authors.library.caltech.edu/records/67wk5-bgq95", "eprint_id": 122160, "eprint_status": "archive", "datestamp": "2023-08-22 17:56:45", "lastmod": "2025-11-20 18:41:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rustgi-Sachin", "name": { "family": "Rustgi", "given": "Sachin" }, "orcid": "0000-0002-6881-9501" }, { "id": "Naveed-Salman", "name": { "family": "Naveed", "given": "Salman" }, "orcid": "0000-0002-0248-9490" }, { "id": "Windham-Jonathan", "name": { "family": "Windham", "given": "Jonathan" } }, { "id": "Zhang-Huan", "name": { "family": "Zhang", "given": "Huan" }, "orcid": "0000-0002-1096-4255" }, { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" } ] }, "title": "Plant biomacromolecule delivery methods in the 21st century", "ispublished": "pub", "full_text_status": "public", "keywords": "biomacromolecule delivery methods, genome editing, CRISPR, RNA interference, genetic transformation, site-directed mutagenesis, nanoparticles, plants; General Medicine", "note": "\u00a9 2022 Rustgi, Naveed, Windham, Zhang and Demirer. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. \n\nThis work was supported by grants from Clemson University (Clemson SEED), National Institute of Food and Agriculture (NIFA Multi-state grant S009), SC Peanut Board, National Peanut Board, and Foundation for Food & Agriculture Research (FFAR) to SR. GD is supported by the Resnick Sustainability Institute at California Institute of Technology. HZ acknowledges the support from Natural Science Foundation of Guangdong Province of China (2022A1515011839). \n\nAuthor contributions. SR, SN, JW, HZ, and GD wrote the manuscript. GD designed the figure. SR contributed to the conception. All authors contributed to the revision, editing, and approval of the manuscript. \n\nThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\n\n

Published - fgeed-04-1011934.pdf

", "abstract": "The 21st century witnessed a boom in plant genomics and gene characterization studies through RNA interference and site-directed mutagenesis. Specifically, the last 15\u00a0years marked a rapid increase in discovering and implementing different genome editing techniques. Methods to deliver gene editing reagents have also attempted to keep pace with the discovery and implementation of gene editing tools in plants. As a result, various transient/stable, quick/lengthy, expensive (requiring specialized equipment)/inexpensive, and versatile/specific (species, developmental stage, or tissue) methods were developed. A brief account of these methods with emphasis on recent developments is provided in this review article. Additionally, the strengths and limitations of each method are listed to allow the reader to select the most appropriate method for their specific studies. Finally, a perspective for future developments and needs in this research area is presented.", "date": "2022-10-14", "date_type": "published", "publication": "Frontiers in Genome Editing", "volume": "4", "publisher": "Frontiers Media SA", "pagerange": "Art. No. 1011934", "id_number": "CaltechAUTHORS:20230705-476466000.32", "issn": "2673-3439", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230705-476466000.32", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Clemson University" }, { "agency": "National Institute of Food and Agriculture", "grant_number": "S009" }, { "agency": "South Carolina Peanut Board" }, { "agency": "National Peanut Board" }, { "agency": "Foundation for Food and Agriculture Research" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Natural Science Foundation of Guangdong Province of China", "grant_number": "2022A1515011839" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3389/fgeed.2022.1011934", "pmcid": "PMC9614364", "primary_object": { "basename": "fgeed-04-1011934.pdf", "url": "https://authors.library.caltech.edu/records/67wk5-bgq95/files/fgeed-04-1011934.pdf" }, "pub_year": "2022", "author_list": "Rustgi, Sachin; Naveed, Salman; et al." }, { "id": "https://authors.library.caltech.edu/records/pvbnj-1nm65", "eprint_id": 117306, "eprint_status": "archive", "datestamp": "2023-08-22 17:43:11", "lastmod": "2025-11-21 03:33:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pan-Xiang", "name": { "family": "Pan", "given": "Xiang" }, "orcid": "0000-0002-6565-2339" }, { "id": "Chen-Minghua", "name": { "family": "Chen", "given": "Minghua" }, "orcid": "0000-0003-4763-0037" }, { "id": "Zhao-Tianyu", "name": { "family": "Zhao", "given": "Tianyu" }, "orcid": "0000-0002-9541-0197" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "DeepOPF: A Feasibility-Optimized Deep Neural Network Approach for AC Optimal Power Flow Problems", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; Control and Systems Engineering; Computer Networks and Communications; Computer Science Applications; Information Systems", "note": "This work was supported in part by the General Research Fund from Research Grants Council, Hong Kong under Grant 11203122, in part by the InnoHK initiative, The Government of the HKSAR, and Laboratory for AI-Powered Financial Technologies, and in part by the NSF through grants ECCS under Grant 1931662, Caltech Resnick, S2I funds, and C3.ai/UC Berkeley. \n\nThe authors would like to thank T. Cui, W. Huang, Q. Lin, and A. Venzke for the discussions related to this study, and Y. Guo and the National Supercomputer Center in Jinan for providing GPU/CPU computing resources. They also would like to thank the anonymous reviewers for careful reading and the helpful comments.", "abstract": "To cope with increasing uncertainty from renewable generation and flexible load, grid operators need to solve alternative current optimal power flow (AC-OPF) problems more frequently for efficient and reliable operation. In this article, we develop a deep neural network (DNN) approach, called DeepOPF, for solving AC-OPF problems in a fraction of the time used by conventional iterative solvers. A key difficulty for applying machine learning techniques for solving AC-OPF problems lies in ensuring that the obtained solutions respect the equality and inequality physical and operational constraints. Generalized a prediction-and-reconstruction procedure in our previous studies, DeepOPF first trains a DNN model to predict a set of independent operating variables and then directly compute the remaining ones by solving the power flow equations. Such an approach not only preserves the power-flow balance equality constraints but also reduces the number of variables to be predicted by the DNN, cutting down the number of neurons and training data needed. DeepOPF then employs a penalty approach with a zero-order gradient estimation technique in the training process toward guaranteeing the inequality constraints. We also drive a condition for tuning the DNN size according to the desired approximation accuracy, which measures its generalization capability. It provides theoretical justification for using DNN to solve AC-OPF problems. Simulation results for IEEE 30/118/300-bus and a synthetic 2000-bus test cases demonstrate the effectiveness of the penalty approach. They also show that DeepOPF speeds up the computing time by up to two orders of magnitude as compared to a state-of-the-art iterative solver, at the expense of < 0.2% cost difference.", "date": "2022-10-14", "date_type": "published", "publication": "IEEE Systems Journal", "publisher": "IEEE", "id_number": "CaltechAUTHORS:20221010-454096500.22", "issn": "1932-8184", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221010-454096500.22", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Research Grants Council of Hong Kong", "grant_number": "11203122" }, { "agency": "InnoHK initiative" }, { "agency": "Government of the HKSAR" }, { "agency": "Laboratory for AI-Powered Financial Technologies" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of California, Berkeley" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/jsyst.2022.3201041", "pub_year": "2022", "author_list": "Pan, Xiang; Chen, Minghua; et al." }, { "id": "https://authors.library.caltech.edu/records/639rk-cy964", "eprint_id": 117360, "eprint_status": "archive", "datestamp": "2023-08-22 17:54:58", "lastmod": "2025-11-20 20:21:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lawniczak-James-J", "name": { "family": "Lawniczak", "given": "James J." }, "orcid": "0000-0003-1898-9809" }, { "id": "Zhang-Xinglong", "name": { "family": "Zhang", "given": "Xinglong" }, "orcid": "0000-0003-1698-692X" }, { "id": "Christianson-Matthew", "name": { "family": "Christianson", "given": "Matthew" }, "orcid": "0000-0003-2889-0335" }, { "id": "Bailey-Brad-C", "name": { "family": "Bailey", "given": "Brad" } }, { "id": "Bremer-Sean", "name": { "family": "Bremer", "given": "Sean" } }, { "id": "Barcia-Sarah", "name": { "family": "Barcia", "given": "Sarah" } }, { "id": "Mukhopadhyay-Sukrit", "name": { "family": "Mukhopadhyay", "given": "Sukrit" } }, { "id": "Klosin-Jerzy", "name": { "family": "Klosin", "given": "Jerzy" }, "orcid": "0000-0002-9045-7308" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Solution-Phase Conformational/Vibrational Anharmonicity in Comonomer Incorporation Polyolefin Catalysis", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry", "note": "We acknowledge Peter Margl for his support in this project. This work was carried out with financial support from the University Partnership Initiative from the Dow Chemical Company. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under grant no. DGE-1144469. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. X.Z. acknowledges the Agency for Science, Technology and Research (A*STAR), Singapore, for a National Science Scholarship.", "abstract": "The prediction of comonomer incorporation statistics in polyolefin catalysis necessitates an accurate calculation of free energies corresponding to monomer binding and insertion, often requiring sub-kcal/mol resolution to resolve experimental free energies. Batch reactor experiments are used to probe incorporation statistics of ethene and larger \u03b1-olefins for three constrained geometry complexes which are employed as model systems. Herein, over 6 ns of quantum mechanics/molecular mechanics (QM/MM) molecular dynamics is performed in combination with the zero-temperature string method to characterize the solution-phase insertion barrier and to analyze the contributions from conformational and vibrational anharmonicity arising both in vacuum and in solution. Conformational sampling in the solution-phase results in 0\u20132 kcal/mol corrections to the insertion barrier which are on the same scale necessary to resolve experimental free energies. Anharmonic contributions from conformational sampling in the solution phase are crucial energy contributions missing from static density functional theory calculations and implicit solvation models, and the accurate calculation of these contributions is a key step toward the quantitative prediction of comonomer incorporation statistics.", "date": "2022-10-06", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "126", "number": "39", "publisher": "American Chemical Society", "pagerange": "6858-6869", "id_number": "CaltechAUTHORS:20221011-128968500.22", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221011-128968500.22", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Agency for Science, Technology and Research (A*STAR)" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Dow Chemical Company" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpca.2c04038", "pub_year": "2022", "author_list": "Lawniczak, James J.; Zhang, Xinglong; et al." }, { "id": "https://authors.library.caltech.edu/records/2z4ra-3c148", "eprint_id": 117302, "eprint_status": "archive", "datestamp": "2023-08-22 17:53:23", "lastmod": "2025-11-20 21:05:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xuan-Jerry-W", "name": { "family": "Xuan", "given": "Jerry W." }, "orcid": "0000-0002-6618-1137" }, { "id": "Wang-Jason-J", "name": { "family": "Wang", "given": "Jason" }, "orcid": "0000-0003-0774-6502" }, { "id": "Ruffio-Jean-Baptiste", "name": { "family": "Ruffio", "given": "Jean-Baptiste" }, "orcid": "0000-0003-2233-4821" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather A." }, "orcid": "0000-0002-5375-4725" }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "name": { "family": "Molli\u00e8re", "given": "Paul" }, "orcid": "0000-0003-4096-7067" }, { "name": { "family": "Kolecki", "given": "Jared" }, "orcid": "0000-0002-6267-0849" }, { "name": { "family": "Vigan", "given": "Arthur" }, "orcid": "0000-0002-5902-7828" }, { "name": { "family": "Mukherjee", "given": "Sagnick" } }, { "id": "Wallack-Nicole-L", "name": { "family": "Wallack", "given": "Nicole" }, "orcid": "0000-0003-0354-0187" }, { "name": { "family": "Wang", "given": "Ji" }, "orcid": "0000-0002-4361-8885" }, { "id": "Baker-Ashley", "name": { "family": "Baker", "given": "Ashley" }, "orcid": "0000-0002-6525-7013" }, { "id": "Bartos-Randall-D", "name": { "family": "Bartos", "given": "Randall" } }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "name": { "family": "Bond", "given": "Charlotte Z." } }, { "name": { "family": "Bryan", "given": "Marta" }, "orcid": "0000-0002-6076-5967" }, { "id": "Calvin-Benjamin", "name": { "family": "Calvin", "given": "Benjamin" }, "orcid": "0000-0003-4737-5486" }, { "name": { "family": "Cetre", "given": "Sylvain" } }, { "name": { "family": "Chun", "given": "Mark" }, "orcid": "0000-0002-8462-0703" }, { "id": "Delorme-Jacques-Robert", "name": { "family": "Delorme", "given": "Jacques-Robert" }, "orcid": "0000-0001-8953-1008" }, { "name": { "family": "Doppmann", "given": "Greg" } }, { "id": "Echeverri-Daniel", "name": { "family": "Echeverri", "given": "Daniel" }, "orcid": "0000-0002-1583-2040" }, { "name": { "family": "Finnerty", "given": "Luke" }, "orcid": "0000-0002-1392-0768" }, { "name": { "family": "Fitzgerald", "given": "Michael P." }, "orcid": "0000-0002-0176-8973" }, { "id": "Horstman-Katelyn", "name": { "family": "Horstman", "given": "Katelyn" }, "orcid": "0000-0001-9708-8667" }, { "id": "Inglis-Julie", "name": { "family": "Inglis", "given": "Julie" } }, { "id": "Jovanovic-Nemanja", "name": { "family": "Jovanovic", "given": "Nemanja" }, "orcid": "0000-0001-5213-6207" }, { "name": { "family": "L\u00f3pez", "given": "Ronald" } }, { "name": { "family": "Martin", "given": "Emily C." }, "orcid": "0000-0002-0618-5128" }, { "name": { "family": "Morris", "given": "Evan" } }, { "id": "Pezzato-Jacklyn", "name": { "family": "Pezzato", "given": "Jacklyn" }, "orcid": "0000-0002-6769-2035" }, { "name": { "family": "Ragland", "given": "Sam" } }, { "id": "Ren-Bin", "name": { "family": "Ren", "given": "Bin" }, "orcid": "0000-0003-1698-9696" }, { "id": "Ruane-Garreth-J", "name": { "family": "Ruane", "given": "Garreth" }, "orcid": "0000-0003-4769-1665" }, { "name": { "family": "Sappey", "given": "Ben" } }, { "id": "Schofield-Tobias", "name": { "family": "Schofield", "given": "Tobias" } }, { "name": { "family": "Skemer", "given": "Andrew" }, "orcid": "0000-0001-6098-3924" }, { "name": { "family": "Venenciano", "given": "Taylor" } }, { "id": "Wallace-J-Kent", "name": { "family": "Wallace", "given": "J. Kent" }, "orcid": "0000-0001-5299-6899" }, { "name": { "family": "Wizinowich", "given": "Peter" }, "orcid": "0000-0002-1646-442X" } ] }, "title": "A Clear View of a Cloudy Brown Dwarf Companion from High-resolution Spectroscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "We wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. This research has benefitted from the SpeX Prism Library maintained by Adam Burgasser at http://www.browndwarfs.org/spexprism. Funding for KPIC has been provided by the California Institute of Technology, the Jet Propulsion Laboratory, the Heising-Simons Foundation, the Simons Foundation, and the United States National Science Foundation grant No. AST-1611623. A.V. acknowledges funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, grant agreement Nos. 757561 (HiRISE). H.A.K. acknowledges support from the President's and Director's Research & Development Fund Program, which is jointly funded by the Jet Propulsion Laboratory and the California Institute of Technology under a contract with the National Aeronautics and Space Administration. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.", "abstract": "Direct imaging studies have mainly used low-resolution spectroscopy (R \u223c 20\u2013100) to study the atmospheres of giant exoplanets and brown dwarf companions, but the presence of clouds has often led to degeneracies in the retrieved atmospheric abundances (e.g., carbon-to-oxygen ratio, metallicity). This precludes clear insights into the formation mechanisms of these companions. The Keck Planet Imager and Characterizer (KPIC) uses adaptive optics and single-mode fibers to transport light into NIRSPEC (R \u223c 35,000 in the K band), and aims to address these challenges with high-resolution spectroscopy. Using an atmospheric retrieval framework based on petitRADTRANS, we analyze the KPIC high-resolution spectrum (2.29\u20132.49 \u03bcm) and the archival low-resolution spectrum (1\u20132.2 \u03bcm) of the benchmark brown dwarf HD 4747 B (m = 67.2 \u00b1 1.8 M_(Jup), a = 10.0 \u00b1 0.2 au, T_(eff) \u2248 1400 K). We find that our measured C/O and metallicity for the companion from the KPIC high-resolution spectrum agree with those of its host star within 1\u03c3\u20132\u03c3. The retrieved parameters from the K-band high-resolution spectrum are also independent of our choice of cloud model. In contrast, the retrieved parameters from the low-resolution spectrum are highly sensitive to our chosen cloud model. Finally, we detect CO, H\u2082O, and CH\u2084 (volume-mixing ratio of log(CH\u2084) = \u22124.82 \u00b1 0.23) in this L/T transition companion with the KPIC data. The relative molecular abundances allow us to constrain the degree of chemical disequilibrium in the atmosphere of HD 4747 B, and infer a vertical diffusion coefficient that is at the upper limit predicted from mixing length theory.", "date": "2022-10-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "937", "number": "2", "publisher": "American Astronomical Society", "pagerange": "54Art. No.", "id_number": "CaltechAUTHORS:20221010-454096500.18", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221010-454096500.18", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Simons Foundation" }, { "agency": "NSF", "grant_number": "AST-1611623" }, { "agency": "European Research Council (ERC)", "grant_number": "757561" }, { "agency": "JPL President and Director's Fund" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/1538-4357/ac8673", "pub_year": "2022", "author_list": "Xuan, Jerry W.; Wang, Jason; et al." }, { "id": "https://authors.library.caltech.edu/records/55c4m-41492", "eprint_id": 116160, "eprint_status": "archive", "datestamp": "2023-08-22 17:48:29", "lastmod": "2025-11-21 03:19:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Spero-Melanie-A", "name": { "family": "Spero", "given": "Melanie A." }, "orcid": "0000-0003-3291-2138" }, { "id": "Jones-Jeffrey-J", "name": { "family": "Jones", "given": "Jeff" }, "orcid": "0000-0002-7142-2222" }, { "id": "Lomenick-Brett", "name": { "family": "Lomenick", "given": "Brett" }, "orcid": "0000-0002-5023-9998" }, { "id": "Chou-Tsui-Fen", "name": { "family": "Chou", "given": "Tsui-Fen" }, "orcid": "0000-0003-2410-2186" }, { "id": "Newman-D-K", "name": { "family": "Newman", "given": "Dianne K." }, "orcid": "0000-0003-1647-1918" } ] }, "title": "Mechanisms of chlorate toxicity and resistance in Pseudomonas aeruginosa", "ispublished": "pub", "full_text_status": "public", "keywords": "Molecular Biology; Microbiology", "note": "\u00a9 2022 John Wiley & Sons. \n\nAccepted manuscript online: 08 August 2022. Manuscript accepted: 04 August 2022. Manuscript revised: 31 July 2022. Manuscript received: 25 April 2022. \n\nGrants to D.K.N. from the NIH (1R21AI146987-02) and the Doren Family Foundation supported this research. M.A.S. was supported by a postdoctoral fellowship from the Cystic Fibrosis Foundation (SPERO19F0). We thank Megan Bergkessel (University of Dundee) for help with Tn-seq analyses, including providing custom scripts, and Nathan Dalleska and the Resnick Water and Environment Laboratory (Caltech) for help with metabolite analyses. We also thank John Bettinger for providing the python code used to analyze methionine oxidation levels via the \u00b9\u2078O-H\u2082O\u2082 labeling method that he and colleagues developed (Bettinger et al.) The Proteome Exploration Laboratory was supported by NIH OD010788, NIH OD020013, the Betty and Gordon Moore Foundation through grant GBMF775 and the Beckman Institute at Caltech. \n\nData Availability Statement: The proteomic data that supports the findings of this study are openly available in PRIDE at http://www.ebi.ac.uk/pride, accession number PXD033396.\n\n

Accepted Version - Molecular_Microbiology_-_2022_-_Spero_-_Mechanisms_of_chlorate_toxicity_and_resistance_in_Pseudomonas_aeruginosa.pdf

Supplemental Material - mmi14972-sup-0001-figs1-s3.docx

Supplemental Material - mmi14972-sup-0002-tables1.xlsx

Supplemental Material - mmi14972-sup-0003-tables2.xlsx

Supplemental Material - mmi14972-sup-0004-tables3.xlsx

Supplemental Material - mmi14972-sup-0005-tables4.xlsx

Supplemental Material - mmi14972-sup-0006-tables5.xlsx

", "abstract": "Pseudomonas aeruginosa is an opportunistic bacterial pathogen that often encounters hypoxic/anoxic environments within the host, which increases its tolerance to many conventional antibiotics. Towards identifying novel treatments, we explored the therapeutic potential of chlorate, a pro-drug that kills hypoxic/anoxic, antibiotic-tolerant P. aeruginosa populations. While chlorate itself is relatively nontoxic, it is enzymatically reduced to the toxic oxidizing agent, chlorite, by hypoxically-induced nitrate reductase. To better assess chlorate's therapeutic potential, we investigated mechanisms of chlorate toxicity and resistance in P. aeruginosa. We used transposon mutagenesis to identify genes that alter P. aeruginosa fitness during chlorate treatment, finding that methionine sulfoxide reductases (Msr), which repair oxidized methionine residues, support survival during chlorate stress. Chlorate treatment leads to proteome-wide methionine oxidation, which is exacerbated in a \u2206msrA\u2206msrB strain. In response to chlorate, P. aeruginosa upregulates proteins involved in a wide range of functions, including metabolism, DNA replication/repair, protein repair, transcription, and translation, and these newly synthesized proteins are particularly vulnerable to methionine oxidation. The addition of exogenous methionine partially rescues P. aeruginosa survival during chlorate treatment, suggesting that widespread methionine oxidation contributes to death. Finally, we found that mutations that decrease nitrate reductase activity are a common mechanism of chlorate resistance.", "date": "2022-10", "date_type": "published", "publication": "Molecular Microbiology", "volume": "118", "number": "4", "publisher": "Wiley", "pagerange": "321-335", "id_number": "CaltechAUTHORS:20220808-223822000", "issn": "0950-382X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220808-223822000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "1R21AI146987-02" }, { "agency": "Doren Family Foundation" }, { "agency": "Cystic Fibrosis Foundation", "grant_number": "SPERO19F0" }, { "agency": "NIH", "grant_number": "OD010788" }, { "agency": "NIH", "grant_number": "OD020013" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF775" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1111/mmi.14972", "pmcid": "PMC9589919", "primary_object": { "basename": "mmi14972-sup-0003-tables2.xlsx", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/mmi14972-sup-0003-tables2.xlsx" }, "related_objects": [ { "basename": "mmi14972-sup-0004-tables3.xlsx", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/mmi14972-sup-0004-tables3.xlsx" }, { "basename": "mmi14972-sup-0005-tables4.xlsx", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/mmi14972-sup-0005-tables4.xlsx" }, { "basename": "mmi14972-sup-0006-tables5.xlsx", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/mmi14972-sup-0006-tables5.xlsx" }, { "basename": "Molecular_Microbiology_-_2022_-_Spero_-_Mechanisms_of_chlorate_toxicity_and_resistance_in_Pseudomonas_aeruginosa.pdf", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/Molecular_Microbiology_-_2022_-_Spero_-_Mechanisms_of_chlorate_toxicity_and_resistance_in_Pseudomonas_aeruginosa.pdf" }, { "basename": "mmi14972-sup-0001-figs1-s3.docx", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/mmi14972-sup-0001-figs1-s3.docx" }, { "basename": "mmi14972-sup-0002-tables1.xlsx", "url": "https://authors.library.caltech.edu/records/55c4m-41492/files/mmi14972-sup-0002-tables1.xlsx" } ], "pub_year": "2022", "author_list": "Spero, Melanie A.; Jones, Jeff; et al." }, { "id": "https://authors.library.caltech.edu/records/ctqqz-e7064", "eprint_id": 115751, "eprint_status": "archive", "datestamp": "2024-01-18 17:07:06", "lastmod": "2025-11-21 01:54:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Turro-Raymond-F", "name": { "family": "Turro", "given": "Raymond F." }, "orcid": "0000-0001-9774-4556" }, { "id": "Brandst\u00e4tter-Marco", "name": { "family": "Brandst\u00e4tter", "given": "Marco" }, "orcid": "0000-0002-9465-7585" }, { "id": "Reisman-S-E", "name": { "family": "Reisman", "given": "Sarah E." }, "orcid": "0000-0001-8244-9300" } ] }, "title": "Nickel\u2010Catalyzed Reductive Alkylation of Heteroaryl Imines", "ispublished": "pub", "full_text_status": "public", "keywords": "imine alkylation; cross-electrophile coupling; nickel-catalyzed; electroreductive; redox non-innocent; General Chemistry; Catalysis", "note": "\u00a9 2022 Wiley-VCH GmbH. \n\nAccepted manuscript online: 05 July 2022. Manuscript accepted: 04 July 2022. Manuscript revised: 01 July 2022. Manuscript received: 23 May 2022. \n\nDr. Scott Virgil and the Caltech Center for Catalysis and Chemical Synthesis are gratefully acknowledged for access to analytical equipment. Fellowship support was provided by the Swiss National Science Foundation (M. B.). S.E.R. is a Heritage Medical Research Institute Investigator and acknowledges financial support from the NIH (R35GM118191). The authors would also like to thank Dr. Nathan Dalleska and the Resnick Sustainability Institute's Water and Environmental Lab for elemental analysis of commercial manganese; Dr. Mona Shahgholi for assistance with mass spectrometry measurements; Dr. Paul Oyala for assistance with X-band EPR measurements; Dr. David E. Hill for invaluable assistance with electroanalytical and spectroelectrochemical experiments; as well as Z. Jaron Tong for helpful discussions on DFT calculations and non-innocent ligand complexes.\n\n

Accepted Version - Angew_Chem_Int_Ed_-_2022_-_Turro_-_Nickel\u2010Catalyzed_Reductive_Alkylation_of_Heteroaryl_Imines.pdf

Supplemental Material - anie202207597-s1-2022-6-26_imineexp_si_combined.pdf

", "abstract": "A Ni-catalyzed reductive cross-coupling of heteroaryl imines with C(sp\u00b3) electrophiles for the preparation of heterobenzylic amines is reported. This umpolung-type alkylation proceeds under mild conditions, avoids the pre-generation of organometallic reagents, and exhibits good functional group tolerance. Mechanistic studies are consistent with the imine substrate acting as a redox-active ligand upon coordination to a low-valent Ni center. The resulting bis(2-imino)heterocycle\u00b7Ni complexes can engage in alkylation reactions with a variety of C(sp\u00b3) electrophiles, giving heterobenzylic amine products in good yields.", "date": "2022-09-19", "date_type": "published", "publication": "Angewandte Chemie International Edition", "publisher": "Wiley", "id_number": "CaltechAUTHORS:20220721-9036000", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220721-9036000", "funders": { "items": [ { "agency": "Swiss National Science Foundation (SNSF)" }, { "agency": "Heritage Medical Research Institute" }, { "agency": "NIH", "grant_number": "R35GM118191" } ] }, "local_group": { "items": [ { "id": "Heritage-Medical-Research-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.202207597", "primary_object": { "basename": "Angew_Chem_Int_Ed_-_2022_-_Turro_-_Nickel\u2010Catalyzed_Reductive_Alkylation_of_Heteroaryl_Imines.pdf", "url": "https://authors.library.caltech.edu/records/ctqqz-e7064/files/Angew_Chem_Int_Ed_-_2022_-_Turro_-_Nickel\u2010Catalyzed_Reductive_Alkylation_of_Heteroaryl_Imines.pdf" }, "related_objects": [ { "basename": "anie202207597-s1-2022-6-26_imineexp_si_combined.pdf", "url": "https://authors.library.caltech.edu/records/ctqqz-e7064/files/anie202207597-s1-2022-6-26_imineexp_si_combined.pdf" }, { "basename": "nihms-1821913.pdf", "url": "https://authors.library.caltech.edu/records/ctqqz-e7064/files/nihms-1821913.pdf" } ], "pub_year": "2022", "author_list": "Turro, Raymond F.; Brandst\u00e4tter, Marco; et al." }, { "id": "https://authors.library.caltech.edu/records/6yhyp-zmg10", "eprint_id": 118231, "eprint_status": "archive", "datestamp": "2023-08-22 17:39:45", "lastmod": "2025-11-21 00:50:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cui-Zhi-Hao", "name": { "family": "Cui", "given": "Zhi-Hao" }, "orcid": "0000-0002-7389-4063" }, { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Zhang-Xing", "name": { "family": "Zhang", "given": "Xing" }, "orcid": "0000-0002-1892-1380" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Systematic electronic structure in the cuprate parent state from quantum many-body simulations", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "We thank T. Zhu, L. Peng, Y. Li, P. Lee, A. Millis, and S. White for helpful discussions. \n\nThis work was primarily supported by the US Department of Energy, Office of Science, through grant DE-SC0018140. The DMRG calculations were performed using the block2 code, which was developed with funding from the US National Science Foundation through grant CHE-2102505. This work also relied on improvements to the pyscf density fitting and integral transformation modules, carried out as part of work supported by the Center for Molecular Magnetic Quantum Materials, an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Basic Energy Sciences, under award DE-SC0019330. G.K.-L.C. is a Simons Investigator in Physics and is part of the Simons Collaboration on the Many-Electron Problem. Z.-H.C. acknowledges support from the Eddleman Quantum Institute through a graduate fellowship. Calculations were conducted in the Resnick High Performance Computing Center, supported by the Resnick Sustainability Institute at Caltech, and National Energy Research Scientific Computing Center (NERSC), a US Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory.", "abstract": "The quantitative description of correlated electron materials remains a modern computational challenge. We demonstrate a numerical strategy to simulate correlated materials at the fully ab initio level beyond the solution of effective low-energy models and apply it to gain a detailed microscopic understanding across a family of cuprate superconducting materials in their parent undoped states. We uncover microscopic trends in the electron correlations and reveal the link between the material composition and magnetic energy scales through a many-body picture of excitation processes involving the buffer layers. Our work illustrates a path toward a quantitative and reliable understanding of more complex states of correlated materials at the ab initio many-body level.", "date": "2022-09-08", "date_type": "published", "publication": "Science", "volume": "377", "number": "6611", "publisher": "American Association for the Advancement of Science", "pagerange": "1192-1198", "id_number": "CaltechAUTHORS:20221205-666301600.3", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221205-666301600.3", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0018140" }, { "agency": "NSF", "grant_number": "CHE-2102505" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019330" }, { "agency": "Simons Foundation" }, { "agency": "Eddleman Quantum Institute" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/science.abm2295", "pub_year": "2022", "author_list": "Cui, Zhi-Hao; Zhai, Huanchen; et al." }, { "id": "https://authors.library.caltech.edu/records/87q26-t3445", "eprint_id": 116716, "eprint_status": "archive", "datestamp": "2023-08-22 17:38:59", "lastmod": "2025-11-20 18:34:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Larsson-Henrik-R", "name": { "family": "Larsson", "given": "Henrik R." }, "orcid": "0000-0002-9417-1518" }, { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Umrigar-Cyrus-J", "name": { "family": "Umrigar", "given": "C. J." } }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "The Chromium Dimer: Closing a Chapter of Quantum Chemistry", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "\u00a9 2022 The Authors. Published by American Chemical Society. Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/).\n\nWe thank Doreen Leopold and Alec Wodtke for helpful discussions. Work by G.K.C. was supported by the US National Science Foundation (NSF) via grant no. CHE2102505. G.K.C. acknowledges additional support from the Simons Foundation via the Many-Electron Collaboration and the Investigator Award. Work by H.R.L., H.Z., and C.J.U. was\nsupported by the Air Force Office of Scientific Research, under Award FA9550-18-1-0095. H.R.L. acknowledges support from a postdoctoral fellowship from the German Research\nFoundation (DFG) via grant LA 4442/1-1 during the first part of this work. Some of the computations were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. The SHCI calculations were performed on the Bridges computer at the Pittsburgh Supercomputing Center under grant PHY170037. \n\nData for reproducing Figure 2a is available at https://github.com/h-larsson/Cr2Pes22. Further data is available from the authors upon reasonable request. \n\nThe authors declare the following competing financial interest(s): G.K.C. is part-owner of QSimulate, Inc.\n\n

Published - ja2c06357.pdf

Supplemental Material - ja2c06357_si_001.pdf

", "abstract": "The complex electronic structure and unusual potential energy curve of the chromium dimer have fascinated scientists for decades, with agreement between theory and experiment so far elusive. Here, we present a new ab initio simulation of the potential energy curve and vibrational spectrum that significantly improves on all earlier estimates. Our data support a shift in earlier experimental assignments of a cluster of vibrational frequencies by one quantum number. The new vibrational assignment yields an experimentally derived potential energy curve in quantitative agreement with theory across all bond lengths and across all\nmeasured frequencies. By solving this long-standing problem, our results raise the possibility of quantitative quantum chemical modeling of transition metal clusters with spectroscopic accuracy.", "date": "2022-09-07", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "144", "number": "35", "publisher": "American Chemical Society", "pagerange": "15932-15937", "id_number": "CaltechAUTHORS:20220908-232209149", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220908-232209149", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-2102505" }, { "agency": "Simons Foundation" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0095" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "LA 4442/1-1" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "PHY-170037" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.2c06357", "pmcid": "PMC9460780", "primary_object": { "basename": "ja2c06357.pdf", "url": "https://authors.library.caltech.edu/records/87q26-t3445/files/ja2c06357.pdf" }, "related_objects": [ { "basename": "ja2c06357_si_001.pdf", "url": "https://authors.library.caltech.edu/records/87q26-t3445/files/ja2c06357_si_001.pdf" } ], "pub_year": "2022", "author_list": "Larsson, Henrik R.; Zhai, Huanchen; et al." }, { "id": "https://authors.library.caltech.edu/records/yyt5g-92308", "eprint_id": 117444, "eprint_status": "archive", "datestamp": "2023-09-29 21:42:40", "lastmod": "2025-11-20 23:44:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zott-Michael-D", "name": { "family": "Zott", "given": "Michael D." } }, { "id": "Canestraight-Virginia-M", "name": { "family": "Canestraight", "given": "Virginia M." } }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Mechanism of a Luminescent Dicopper System That Facilitates Electrophotochemical Coupling of Benzyl Chlorides via a Strongly Reducing Excited State", "ispublished": "pub", "full_text_status": "public", "keywords": "Catalysis; General Chemistry", "note": "The authors are grateful to the National Institutes of Health (NIGMS: R01-109194) for support of this research. M.D.Z. acknowledges the Resnick Sustainability Institute at Caltech and the National Science Foundation (DGE-1745301) for support via Graduate Fellowships. V.M.C. acknowledges the John Stauffer Charitable Trust and Caltech's Summer Undergraduate Research Fellowships program for summer research funding. The Beckman Institute Laser Resource Center and Jay R. Winkler are acknowledged for providing support with steady-state and time-resolved luminescence experiments. We acknowledge Dr. Joseph Derosa for insightful discussions.", "abstract": "Photochemical radical generation has become a modern staple in chemical synthesis and methodology. Herein, we detail the photochemistry of a highly reducing, highly luminescent dicopper system [Cu\u2082] (E\u2092\u2093* \u2248 \u22122.7 V vs SCE; \u03c4\u2092 \u2248 10 \u03bcs) within the context of a model reaction: single-electron reduction of benzyl chlorides. The dicopper system is mechanistically well defined. As we show, it is the [Cu\u2082]* excited state that serves as the outer-sphere photoreductant of benzyl chloride substrates; the ground-state oxidized byproduct, [Cu\u2082]\u207a, is electrochemically recycled, demonstrating a catalytic electrophotochemical C\u2013C coupling process.", "date": "2022-09-02", "date_type": "published", "publication": "ACS Catalysis", "volume": "12", "number": "17", "publisher": "American Chemical Society", "pagerange": "10781-10786", "id_number": "CaltechAUTHORS:20221017-10817000.2", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221017-10817000.2", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01-109194" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "John Stauffer Charitable Trust" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscatal.2c03215", "pmcid": "PMC10306173", "primary_object": { "basename": "nihms-1900343.pdf", "url": "https://authors.library.caltech.edu/records/yyt5g-92308/files/nihms-1900343.pdf" }, "related_objects": [ { "basename": "NIHMS1900343-supplement-Supporting_Information__Experimental_procedures__spectroscopic_characterization__e_g___NMR__data__luminescence_data__description_of_the_Marcus_analysis_performed__kinetic_data_pertaining_to_chloride__Cl___attack_on__.pdf", "url": "https://authors.library.caltech.edu/records/yyt5g-92308/files/NIHMS1900343-supplement-Supporting_Information__Experimental_procedures__spectroscopic_characterization__e_g___NMR__data__luminescence_data__description_of_the_Marcus_analysis_performed__kinetic_data_pertaining_to_chloride__Cl___attack_on__.pdf" }, { "basename": "NIHMS1900343-supplement-SI__Crystallographic_data_for_chloro-cubane_and_chloro-diamond.cif", "url": "https://authors.library.caltech.edu/records/yyt5g-92308/files/NIHMS1900343-supplement-SI__Crystallographic_data_for_chloro-cubane_and_chloro-diamond.cif" } ], "pub_year": "2022", "author_list": "Zott, Michael D.; Canestraight, Virginia M.; et al." }, { "id": "https://authors.library.caltech.edu/records/1zjqe-qa974", "eprint_id": 115422, "eprint_status": "archive", "datestamp": "2023-08-22 17:29:05", "lastmod": "2025-11-20 20:08:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xia-Xiaoxing", "name": { "family": "Xia", "given": "Xiaoxing" }, "orcid": "0000-0003-1255-3289" }, { "id": "Spadaccini-Christopher-M", "name": { "family": "Spadaccini", "given": "Christopher M." }, "orcid": "0000-0002-7074-1459" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Responsive materials architected in space and time", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Materials Chemistry; Surfaces, Coatings and Films; Energy (miscellaneous); Biomaterials; Electronic, Optical and Magnetic Materials", "note": "\u00a9 2022 Springer Nature Limited. \n\nAccepted 10 May 2022. Published 20 June 2022. \n\nThe authors sincerely acknowledge the important contribution to the field of architected materials by J. Goldwasser, who passed away in March 2020 due to COVID-19; during his tenure at DARPA, he supported pioneering efforts in creating architected materials through his programme Materials with Controlled Microstructural Architecture. X.X. acknowledges the financial support from Lawrence Livermore National Laboratory's Lab Directed Research and Development Program (20-FS-032 and 22-ERD-004). J.R.G. acknowledges financial support from the Department of Defense through Vannevar-Bush Faculty Fellowship (ONR grant number N00014-16-1-2827) and the Resnick Sustainability Institute at Caltech. This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. \n\nContributions. All authors contributed equally to the preparation of this manuscript. \n\nThe authors declare no competing interests. \n\nPeer review information. Nature Reviews Materials thanks Qi Ge and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.", "abstract": "Rationally designed architected materials have attained previously untapped territories in materials property space. The properties and behaviours of architected materials need not be stagnant after fabrication; they can be encoded with a temporal degree of freedom such that they evolve over time. In this Review, we describe the variety of materials architected in both space and time, and their responses to various stimuli, including mechanical actuation, changes in temperature and chemical environment, and variations in electromagnetic fields. We highlight the additive manufacturing methods that can precisely prescribe complex geometries and local inhomogeneities to make such responsiveness possible. We discuss the emergent physics phenomena observed in architected materials that are analogous to those in classical materials, such as the formation and behaviour of defects, phase transformations and topologically protected properties. Finally, we offer a perspective on the future of architected materials that have a degree of intelligence through mechanical logic and artificial neural networks.", "date": "2022-09", "date_type": "published", "publication": "Nature Reviews Materials", "volume": "7", "number": "9", "publisher": "Nature Publishing Group", "pagerange": "683-701", "id_number": "CaltechAUTHORS:20220707-978178000", "issn": "2058-8437", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220707-978178000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Lawrence Livermore National Laboratory", "grant_number": "20-FS-032" }, { "agency": "Lawrence Livermore National Laboratory", "grant_number": "22-ERD-004" }, { "agency": "Vannever Bush Faculty Fellowship", "grant_number": "N00014-16-1-2827" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC52-07NA27344" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41578-022-00450-z", "pmcid": "PMC9208549", "pub_year": "2022", "author_list": "Xia, Xiaoxing; Spadaccini, Christopher M.; et al." }, { "id": "https://authors.library.caltech.edu/records/m408r-81q53", "eprint_id": 117649, "eprint_status": "archive", "datestamp": "2023-08-22 17:34:30", "lastmod": "2025-11-21 03:20:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chure-Griffin-D", "name": { "family": "Chure", "given": "Griffin" }, "orcid": "0000-0002-2216-2057" }, { "id": "Banks-Rachel-A", "name": { "family": "Banks", "given": "Rachel A." }, "orcid": "0000-0003-2028-2925" }, { "id": "Flamholz-Avi-I", "name": { "family": "Flamholz", "given": "Avi I." }, "orcid": "0000-0002-9278-5479" }, { "id": "Sarai-Nicholas-S", "name": { "family": "Sarai", "given": "Nicholas S." }, "orcid": "0000-0002-4655-0038" }, { "id": "Kamb-Mason", "name": { "family": "Kamb", "given": "Mason" }, "orcid": "0000-0001-8036-7221" }, { "id": "Lopez-Gomez-Ignacio", "name": { "family": "Lopez-Gomez", "given": "Ignacio" }, "orcid": "0000-0002-7255-5895" }, { "id": "Bar-On-Yinon-M", "name": { "family": "Bar-On", "given": "Yinon" }, "orcid": "0000-0001-8477-609X" }, { "id": "Milo-Ron", "name": { "family": "Milo", "given": "Ron" }, "orcid": "0000-0003-1641-2299" }, { "id": "Phillips-R", "name": { "family": "Phillips", "given": "Rob" }, "orcid": "0000-0003-3082-2809" } ] }, "title": "Anthroponumbers.org: A quantitative database of human impacts on Planet Earth", "ispublished": "pub", "full_text_status": "public", "keywords": "General Decision Sciences", "note": "We are incredibly grateful for the generosity of a wide array of experts for their advice, suggestions, and criticism of this work. Specifically, we thank Suzy Beeler, Joseph Berry, Lars Bildsten, Justin Bois, Chris Bowler, Matthew Burgess, Ken Caldeira, J\u00f6rn Callies, Sean B. Carroll, Ibrahim Ciss\u00e9, Joel Cohen, Michelle Dan, Bethany Ehlmann, Gidon Eshel, Moi Exposito-Alonso, Paul Falkowski, Daniel Fisher, Thomas Frederikse, Neil Fromer, Eric Galbraith, Lea Goentoro, Evan Groover, John Grotzinger, Soichi Hirokawa, Greg Huber, Christina Hueschen, Bob Jaffe, Elizabeth Kolbert, Thomas Lecuit, Raphael Magarik, Jeff Marlow, Brad Marston, Jitu Mayor, Elliot Meyerowitz, Lisa Miller, Dianne Newman, Luke Oltrogge, Nigel Orme, Victoria Orphan, Marco Pasti, Pietro Perona, Noam Prywes, Stephen Quake, Hamza Raniwala, Manuel Razo-Mejia, Thomas Rosenbaum, Benjamin Rubin, Alex Rubinsteyn, Shyam Saladi, Tapio Schneider, Murali Sharma, Alon Shepon, Arthur Smith, Matthieu Talpe, Wati Taylor, Julie Theriot, Tadashi Tokieda, Cat Triandifillou, Sabah Ul-Hasan, Tine Valencic, Ned Wingreen, and Emily Zakem. We also thank Yue Qin for sharing data related to global water consumption. Many of the topics in this work began during the Applied Physics 150C course taught at Caltech during the early days of the COVID-19 pandemic. This work was supported by the Resnick Sustainability Institute at Caltech and the Schwartz-Reisman Collaborative Science Program at the Weizmann Institute of Science. G.C. acknowledges support by the NSF Postdoctoral Research Fellowships in Biology Program (grant no. 2010807).\n\n

Published - 1-s2.0-S266638992200157X-main.pdf

Supplemental Material - 1-s2.0-S266638992200157X-mmc1.pdf

Supplemental Material - 1-s2.0-S266638992200157X-mmc2.pdf

Supplemental Material - 1-s2.0-S266638992200157X-mmc3.pdf

", "abstract": "Over the last 10,000 years, human activities have transformed Earth through farming, forestry, mining, and industry. The complex results of these activities are now observed and quantified as \"human impacts\" on Earth's atmosphere, oceans, biosphere, and geochemistry. While myriad studies have explored facets of human impacts on the planet, they are necessarily technical and often highly focused. Thus, finding reliable quantitative information requires a significant investment of time to assess each quantity and associated uncertainty. We present the Human Impacts Database (www.anthroponumbers.org), which houses a diverse array of such quantities. We review a subset of these values and how they help build intuition for understanding the Earth-human system. While collation alone does not tell us how to best ameliorate human impacts, we contend that any future plans should be made in light of a quantitative understanding of the interconnected ways in which humans influence the planet.", "date": "2022-09", "date_type": "published", "publication": "Patterns", "volume": "3", "number": "9", "publisher": "Elsevier", "pagerange": "Art. No. 100552", "id_number": "CaltechAUTHORS:20221031-575177800.5", "issn": "2666-3899", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221031-575177800.5", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Weizmann Institute of Science" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DBI-2010807" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1016/j.patter.2022.100552", "pmcid": "PMC9481956", "primary_object": { "basename": "1-s2.0-S266638992200157X-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/m408r-81q53/files/1-s2.0-S266638992200157X-mmc1.pdf" }, "related_objects": [ { "basename": "1-s2.0-S266638992200157X-mmc2.pdf", "url": "https://authors.library.caltech.edu/records/m408r-81q53/files/1-s2.0-S266638992200157X-mmc2.pdf" }, { "basename": "1-s2.0-S266638992200157X-mmc3.pdf", "url": "https://authors.library.caltech.edu/records/m408r-81q53/files/1-s2.0-S266638992200157X-mmc3.pdf" }, { "basename": "1-s2.0-S266638992200157X-main.pdf", "url": "https://authors.library.caltech.edu/records/m408r-81q53/files/1-s2.0-S266638992200157X-main.pdf" } ], "pub_year": "2022", "author_list": "Chure, Griffin; Banks, Rachel A.; et al." }, { "id": "https://authors.library.caltech.edu/records/b2a72-cwc02", "eprint_id": 117014, "eprint_status": "archive", "datestamp": "2023-11-20 20:36:27", "lastmod": "2025-11-21 03:43:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Garrido-Barros-Pablo", "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Derosa-Joseph", "name": { "family": "Derosa", "given": "Joseph" }, "orcid": "0000-0001-8672-4875" }, { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Tandem electrocatalytic N\u2082 fixation via proton-coupled electron transfer", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "We thank the Dow Next Generation Educator Funds and Instrumentation Grants for their support of the NMR facility at Caltech. We also thank the Resnick Water and Environment Laboratory (WEL) and the Molecular Materials Resource Center at Caltech for the use of their instrumentation. We thank the following funding agencies: Department of Energy, Office of Basic Energy Sciences (DOE-0235032), Catalysis Science Program (for the development and applications of CPET mediators); National Institutes of Health (R01 GM-075757) (for studies of Fe-mediated N2RR). P.G.-B. thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship. J.D. thanks the Arnold and Mabel Beckman Foundation for a postdoctoral fellowship. M.J.C. thanks the Resnick Sustainability Institute for a graduate fellowship.", "abstract": "New electrochemical ammonia (NH\u2083) synthesis technologies are of interest as a complementary route to the Haber\u2013Bosch process for distributed fertilizer generation, and towards exploiting ammonia as a zero-carbon fuel produced via renewably sourced electricity. Apropos of these goals is a surge of fundamental research targeting heterogeneous materials as electrocatalysts for the nitrogen reduction reaction (N\u2082RR). These systems generally suffer from poor stability and NH\u2083 selectivity; the hydrogen evolution reaction (HER) outcompetes N\u2082RR. Molecular catalyst systems can be exquisitely tuned and offer an alternative strategy, but progress has been thwarted by the same selectivity issue; HER dominates. Here we describe a tandem catalysis strategy that offers a solution to this puzzle. A molecular complex that can mediate an N\u2082 reduction cycle is partnered with a co-catalyst that interfaces the electrode and an acid to mediate proton-coupled electron transfer steps, facilitating N\u2212H bond formation at a favourable applied potential (\u22121.2\u2009V versus Fc\u207a/\u2070) and overall thermodynamic efficiency. Certain intermediates of the N\u2082RR cycle would be otherwise unreactive via uncoupled electron transfer or proton transfer steps. Structurally diverse complexes of several metals (W, Mo, Os, Fe) also mediate N\u2082RR electrocatalysis at the same potential in the presence of the mediator, pointing to the generality of this tandem approach.", "date": "2022-09", "date_type": "published", "publication": "Nature", "volume": "609", "number": "7925", "publisher": "Nature Publishing Group", "pagerange": "71-76", "id_number": "CaltechAUTHORS:20220916-665677000", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220916-665677000", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "NIH", "grant_number": "R01 GM-075757" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Ram\u00f3n Areces Foundation" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41586-022-05011-6", "primary_object": { "basename": "nihms-1900339.pdf", "url": "https://authors.library.caltech.edu/records/b2a72-cwc02/files/nihms-1900339.pdf" }, "pub_year": "2022", "author_list": "Garrido-Barros, Pablo; Derosa, Joseph; et al." }, { "id": "https://authors.library.caltech.edu/records/e2q6b-bk387", "eprint_id": 116355, "eprint_status": "archive", "datestamp": "2023-08-22 17:24:08", "lastmod": "2025-11-20 23:20:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schild-Dirk-J", "name": { "family": "Schild", "given": "Dirk J." }, "orcid": "0000-0003-0179-6023" }, { "id": "Nurdin-Lucie", "name": { "family": "Nurdin", "given": "Lucie" } }, { "id": "Moret-Marc-Etienne", "name": { "family": "Moret", "given": "Marc-Etienne" }, "orcid": "0000-0002-3137-6073" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Characterization of a Proposed Terminal Iron(III) Nitride Intermediate of Nitrogen Fixation Stabilized by a Trisphosphine\u2010Borane Ligand", "ispublished": "pub", "full_text_status": "public", "keywords": "iron nitrides; metal-to-ligand multiple bonds; nitrogen fixation; nitridyl radicals; one-electron sigma bonds; General Chemistry; Catalysis", "note": "\u00a9 2022 Wiley-VCH. \n\nAccepted manuscript online: 16 August 2022. Manuscript accepted: 16 August 2022. Manuscript revised: 15 August 2022. Manuscript received: 04 July 2022. \n\nThe authors are grateful to the National Institutes of Health (NIH GM070757) for funding of this work. The Caltech EPR facility is currently supported by the Dow Next Generation Educator Fund and the Beckman Institute at Caltech. The Beckman Institute is also acknowledged for supporting its X-ray diffraction facility. D. J. S thanks the Resnick Sustainability Institute at Caltech for a graduate fellowship. M.-E. M. acknowledges a Fellowship for Advanced Researchers from the Swiss National Science Foundation.\n\n

Accepted Version - Angew_Chem_Int_Ed_-_2022_-_Schild_-_Characterization_of_a_Proposed_Terminal_Iron_III__Nitride_Intermediate_of_Nitrogen.pdf

Supplemental Material - anie202209655-s1-supporting_information.pdf

", "abstract": "Terminal iron nitrides (Fe\u2261N) have been proposed as intermediates of Fe-mediated nitrogen fixation, and well-defined synthetic iron nitrides have been characterized in high oxidation states, including Fe(IV), Fe(V), and Fe(VI). This study reports the generation and low temperature characterization of a terminally bound iron(III) nitride, P\u2083\u1d2eFe(N) (P\u2083\u1d2e = tris(o-diisopropylphosphinophenyl)borane), which is a proposed intermediate of iron-mediated nitrogen fixation by the P\u2083\u1d2eFe-catalyst system. CW- and pulse EPR spectroscopy (HYSCORE and ENDOR), supported by DFT calculations, help to define a 2A ground state electronic structure of this C\u2083-symmetric nitride species, placing the unpaired spin in a sigma orbital along the B-Fe-N vector; this electronic structure is distinct for an iron nitride. The unusual d\u2075-configuration is stabilized by significant delocalization (~50%) of the unpaired electron onto the axial boron and nitrogen ligands, with a majority of the spin residing on boron.", "date": "2022-08-17", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "61", "number": "43", "publisher": "Wiley", "pagerange": "e202209655", "id_number": "CaltechAUTHORS:20220817-897514000", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220817-897514000", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM070757" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Swiss National Science Foundation (SNSF)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.202209655", "pmcid": "PMC9588675", "primary_object": { "basename": "Angew_Chem_Int_Ed_-_2022_-_Schild_-_Characterization_of_a_Proposed_Terminal_Iron_III__Nitride_Intermediate_of_Nitrogen.pdf", "url": "https://authors.library.caltech.edu/records/e2q6b-bk387/files/Angew_Chem_Int_Ed_-_2022_-_Schild_-_Characterization_of_a_Proposed_Terminal_Iron_III__Nitride_Intermediate_of_Nitrogen.pdf" }, "related_objects": [ { "basename": "anie202209655-s1-supporting_information.pdf", "url": "https://authors.library.caltech.edu/records/e2q6b-bk387/files/anie202209655-s1-supporting_information.pdf" } ], "pub_year": "2022", "author_list": "Schild, Dirk J.; Nurdin, Lucie; et al." }, { "id": "https://authors.library.caltech.edu/records/f2xnx-h3a43", "eprint_status": "archive", "datestamp": "2026-02-05 18:37:08", "lastmod": "2026-02-05 18:40:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sridhar-Akshay", "name": { "family": "Sridhar", "given": "Akshay" }, "orcid": "0000-0002-2642-8246" }, { "name": { "family": "Tissaoui", "given": "Yassine" }, "orcid": "0000-0001-6676-2233" }, { "name": { "family": "Marras", "given": "Simone" }, "orcid": "0000-0002-7498-049X" }, { "id": "Shen-Zhaoyi", "name": { "family": "Shen", "given": "Zhaoyi" }, "orcid": "0000-0002-0444-4720" }, { "id": "Kawczynski-Charles", "name": { "family": "Kawczynski", "given": "Charles" } }, { "id": "Byrne-Simon", "name": { "family": "Byrne", "given": "Simon" }, "orcid": "0000-0001-8048-6810" }, { "id": "Pamnany-Kiran", "name": { "family": "Pamnany", "given": "Kiran" }, "orcid": "0009-0009-2340-3658" }, { "name": { "family": "Waruszewski", "given": "Maciej" }, "orcid": "0009-0001-8918-4314" }, { "name": { "family": "Gibson", "given": "Thomas H." }, "orcid": "0000-0002-7978-6848" }, { "name": { "family": "Kozdon", "given": "Jeremy E." }, "orcid": "0000-0002-2493-4292" }, { "name": { "family": "Churavy", "given": "Valentin" }, "orcid": "0000-0002-9033-165X" }, { "name": { "family": "Wilcox", "given": "Lucas C." } }, { "name": { "family": "Giraldo", "given": "Francis X." }, "orcid": "0000-0001-8965-1202" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "Large-eddy simulations with ClimateMachine v0.2.0: a new open-source code for atmospheric simulations on GPUs and CPUs", "ispublished": "pub", "full_text_status": "public", "note": "

© Author(s) 2022. This work is distributed under the Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union.

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The computations presented here were conducted at the Resnick High-Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology (formerly known as the Central HPC Cluster, with partial support by a grant from the Gordon and Betty Moore Foundation), and on the Google Cloud Platform with in-kind support by Google. We thank the Google team for their assistance with operations on the Google Cloud Platform.

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This research was made possible by the generosity of Eric and Wendy Schmidt by recommendation of the Schmidt Futures program and by the Paul G. Allen Family Foundation, Charles Trimble, the Audi Environmental Foundation, the Heising-Simons Foundation, and the National Science Foundation (grants AGS-1835860 and AGS-1835881). Additionally, Valentin Churavy was supported by the Defense Advanced Research Projects Agency (DARPA, agreement HR0011-20-9-0016) and by the NSF (grant OAC-1835443). Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

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AS contributed to analysis, methodology, software, and writing – review and editing. YT contributed to analysis, visualization, software, and writing – review and editing. SM contributed to conceptualization, methodology, software, and writing – original draft preparation, review, and editing. ZS contributed to software, analysis, visualization, and writing – review and editing. CK developed software. SB developed software. KP developed software and contributed to the analysis. MW was responsible for methodology and software. THG contributed to methodology, software, and writing – review and editing. JEK contributed to conceptualization, methodology, and software. VC developed software. LCW contributed to conceptualization, methodology, and software. FXG contributed to conceptualization, methodology, software, and writing – review and editing. TS contributed to conceptualization, methodology, software, project administration, and writing – original draft preparation, review, and editing.

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At least one of the co-authors is a member of the editorial board of Geoscientific Model Development. The peer-review process was guided by an independent editor, and the authors have no other competing interests to declare.

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ClimateMachine is an open-source framework that is maintained on GitHub: https://github.com/CliMA/ClimateMachine.jl (last access: 20 June 2022). Documentation for installing and running ClimateMachine is available at https://clima.github.io/ClimateMachine.jl/latest/ (last access: 20 June 2022). The version used in this paper is v0.2.0, which can be downloaded from https://doi.org/10.5281/zenodo.5542395 (Climate Modeling Alliance, 2020) or https://github.com/CliMA/ClimateMachine.jl/releases/tag/v0.2.0 (last access: 20 June 2022). The parameters included in Table 1 are available in the accompanying CLIMAParameters.jl Julia package. The code is released under the Apache License, version 2.0

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The test cases presented in the paper are available in the following directory locations in the source code. 

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Sect. 5.1: /test/Numerics/DGMethods/Euler/isentropicvortex.jl

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Sect. 5.2: /tutorials/Atmos/risingbubble.jl

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Sect. 5.3: /tutorials/Atmos/densitycurrent.jl

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Sect. 5.4: /experiments/AtmosLES/schar_scalar_advection.jl

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Sect. 5.5: /experiments/AtmosLES/agnesi_hs_lin.jl and  /experiments/AtmosLES/agnesi_nh_lin.jl

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Sect. 5.6: /experiments/AtmosLES/taylor_green.jl

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Sect. 5.7: /experiments/AtmosLES/bomex_model.jl and  /experiments/AtmosLES/bomex_les.jl

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Configuration instructions and methods for resolution, numerical flux schemes, boundary conditions, and turbulence model specification can be found in the code documentation at https://clima.github.io/ClimateMachine.jl/v0.2/ (Climate Modeling Alliance, 2020). Instructions for installing and launching simulations can be accessed at https://clima.github.io/ClimateMachine.jl/v0.2/GettingStarted/RunningClimateMachine/ (last access: 20 June 2022).

", "abstract": "

We introduce ClimateMachine, a new open-source atmosphere modeling framework which uses the Julia language and is designed to be scalable on central processing units (CPUs) and graphics processing units (GPUs). ClimateMachine uses a common framework both for coarser-resolution global simulations and for high-resolution, limited-area large-eddy simulations (LESs). Here, we demonstrate the LES configuration of the atmosphere model in canonical benchmark cases and atmospheric flows using a total energy-conserving nodal discontinuous Galerkin (DG) discretization of the governing equations. Resolution dependence, conservation characteristics, and scaling metrics are examined in comparison with existing LES codes. They demonstrate the utility of ClimateMachine as a modeling tool for limited-area LES flow configurations.

", "date": "2022-08-12", "date_type": "published", "publication": "Geoscientific Model Development", "volume": "15", "number": "15", "publisher": "European Geosciences Union", "pagerange": "6259-6284", "issn": "1991-9603", "official_url": "https://authors.library.caltech.edu/records/f2xnx-h3a43", "funders": { "items": [ {}, {}, { "grant_number": "AGS-1835860" }, { "grant_number": "AGS-1835881" }, { "grant_number": "HR0011-20-9-0016" }, { "grant_number": "OAC-1835443" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/gmd-15-6259-2022", "primary_object": { "basename": "gmd-15-6259-2022.pdf", "url": "https://authors.library.caltech.edu/records/f2xnx-h3a43/files/gmd-15-6259-2022.pdf" }, "pub_year": "2022", "author_list": "Sridhar, Akshay; Tissaoui, Yassine; et al." }, { "id": "https://authors.library.caltech.edu/records/1q6gn-mvc46", "eprint_id": 116228, "eprint_status": "archive", "datestamp": "2023-08-22 17:19:32", "lastmod": "2025-11-21 00:09:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lopez-Gomez-Ignacio", "name": { "family": "Lopez-Gomez", "given": "Ignacio" }, "orcid": "0000-0002-7255-5895" }, { "id": "Christopoulos-Costa-D", "name": { "family": "Christopoulos", "given": "Costa" }, "orcid": "0000-0002-8552-465X" }, { "id": "Ervik-Haakon-Ludvig-Langeland", "name": { "family": "Ervik", "given": "Haakon Ludvig Langeland" }, "orcid": "0000-0003-2912-5774" }, { "id": "Dunbar-Oliver-R-A", "name": { "family": "Dunbar", "given": "Oliver R. A." }, "orcid": "0000-0001-7374-0382" }, { "id": "Cohen-Yair", "name": { "family": "Cohen", "given": "Yair" }, "orcid": "0000-0002-9615-2476" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "Training physics\u2010based machine\u2010learning parameterizations with gradient\u2010free ensemble Kalman methods", "ispublished": "pub", "full_text_status": "public", "keywords": "Machine learning; Earth system mode; l Subgrid-scale process; Parameterization; Data assimilation; Model calibration; General Earth and Planetary Sciences; Environmental Chemistry; Global and Planetary Change", "note": "\u00a9 2022 American Geophysical Union. \n\nAccepted manuscript online: 10 August 2022. Manuscript accepted: 08 August 2022. Manuscript revised: 22 June 2022. Manuscript received: 24 March 2022. \n\nWe thank Daniel Z. Huang and Zhaoyi Shen for insightful discussions, and Julien Brajard and an anonymous reviewer for prompting a clearer and more precise formulation of the problem and methods discussed in this study. I.L. was supported by a fellowship from the Resnick Sustainability Institute at Caltech, and an Amazon AI4Science fellowship. H.L.L.E was supported by an Aker scholarship and a Fulbright fellowship. This research was additionally supported by the generosity of Eric and Wendy Schmidt by recommendation of the Schmidt Futures program, by the National Science Foundation (grant AGS-1835860), by the Defense Advanced Research Projects Agency (Agreement No. HR00112290030), and by the Heising-Simons Foundation. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The software package implementing ensemble Kalman methods can be accessed at https://doi.org/10.5281/zenodo.6382968, the one implementing the EDMF scheme at https://doi..org/10.5281/zenodo.6392397, and the software used to calibrate the EDMF scheme may be accessed at https://doi.org/10.5281/zenodo.6382865. The data from Shen et al. (2022) used for model training is available at https://doi.org/10.22002/D1.20052.\n\n

Accepted Version - J_Adv_Model_Earth_Syst_-_2022_-_Lopez\u2010Gomez_-_Training_physics\u2010based_machine\u2010learning_parameterizations_with_gradient\u2010free.pdf

", "abstract": "Most machine learning applications in Earth system modeling currently rely on gradient-based supervised learning. This imposes stringent constraints on the nature of the data used for training (typically, residual time tendencies are needed), and it complicates learning about the interactions between machine-learned parameterizations and other components of an Earth system model. Approaching learning about process-based parameterizations as an inverse problem resolves many of these issues, since it allows parameterizations to be trained with partial observations or statistics that directly relate to quantities of interest in long-term climate projections. Here we demonstrate the effectiveness of Kalman inversion methods in treating learning about parameterizations as an inverse problem. We consider two different algorithms: unscented and ensemble Kalman inversion. Both methods involve highly parallelizable forward model evaluations, converge exponentially fast, and do not require gradient computations. In addition, unscented Kalman inversion provides a measure of parameter uncertainty. We illustrate how training parameterizations can be posed as a regularized inverse problem and solved by ensemble Kalman methods through the calibration of an eddy-diffusivity mass-flux scheme for subgrid-scale turbulence and convection, using data generated by large-eddy simulations. We find the algorithms amenable to batching strategies, robust to noise and model failures, and efficient in the calibration of hybrid parameterizations that can include empirical closures and neural networks.", "date": "2022-08-11", "date_type": "published", "publication": "Journal of Advances in Modeling Earth Systems", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2022MS003105", "id_number": "CaltechAUTHORS:20220810-402975000", "issn": "1942-2466", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220810-402975000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Amazon AI4Science Fellowship" }, { "agency": "Aker Scholarship Foundation" }, { "agency": "Fulbright Foundation" }, { "agency": "Schmidt Futures Program" }, { "agency": "NSF", "grant_number": "AGS-1835860" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "HR00112290030" }, { "agency": "Heising-Simons Foundation" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2022ms003105", "primary_object": { "basename": "J_Adv_Model_Earth_Syst_-_2022_-_Lopez\u2010Gomez_-_Training_physics\u2010based_machine\u2010learning_parameterizations_with_gradient\u2010free.pdf", "url": "https://authors.library.caltech.edu/records/1q6gn-mvc46/files/J_Adv_Model_Earth_Syst_-_2022_-_Lopez\u2010Gomez_-_Training_physics\u2010based_machine\u2010learning_parameterizations_with_gradient\u2010free.pdf" }, "pub_year": "2022", "author_list": "Lopez-Gomez, Ignacio; Christopoulos, Costa; et al." }, { "id": "https://authors.library.caltech.edu/records/3pp78-4rf19", "eprint_id": 116161, "eprint_status": "archive", "datestamp": "2023-08-22 17:18:12", "lastmod": "2025-11-20 18:41:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lobo-Ana-H", "name": { "family": "Lobo", "given": "Ana H." }, "orcid": "0000-0003-3862-1817" }, { "id": "Bordoni-S", "name": { "family": "Bordoni", "given": "Simona" }, "orcid": "0000-0003-4771-3350" } ] }, "title": "The Role of Water Vapor in the Response of the Extratropical Circulation of Earth\u2010like Planets to Obliquity Changes", "ispublished": "pub", "full_text_status": "public", "keywords": "High Obliquity; Atmospheric Moisture; Seasonal Cycle; Exoplanet; Baroclinic Eddies; Storm Tracks; Space and Planetary Science; Earth and Planetary Sciences (miscellaneous); Atmospheric Science; Geophysics", "note": "\u00a9 2022 American Geophysical Union. \n\nAccepted manuscript online: 08 August 2022. Manuscript accepted: 23 July 2022. Manuscript revised: 02 June 2022. Manuscript received: 08 October 2021. \n\nThe simulations were conducted on the Caltech Division of Geological and Planetary Sciences CITerra high performance computing cluster, and the Resnick High Performance Computing Cluster. We acknowledge financial support from the Caltech Davidow Discovery Fund. \n\nData Availability. The data used in this study are available at the Caltech Data Repository, DOI:10.22002/D1.20050781 (Lobo & Bordoni, 2022)\n\n

Accepted Version - JGR_Atmospheres_-_2022_-_Lobo_-_The_Role_of_Water_Vapor_in_the_Response_of_the_Extratropical_Circulation_of_Earth\u2010like.pdf

", "abstract": "In this study we use idealized aquaplanet simulations of Earth-like planets to explore the large-scale atmospheric circulation's response to changes in shortwave radiation, through changes in the planet obliquity, and in longwave radiation, through changes in the prescribed optical depth. We primarily focus on the extratropical circulation and the counter-intuitive weakening of extratropical eddy activity, and associated precipitating storm tracks, with increased obliquity. We show that on high obliquity planets with a small surface thermal inertia, net energy deficit during the winter months is primarily balanced by the latent energy component of the atmospheric heat capacity, which buffers any significant atmospheric cooling. As temperatures finally start to decrease, condensational latent heat release of atmospheric moisture further slows down the cooling and keeps the winter pole warmer than the mid latitudes until after the winter solstice. This prevents vigorous baroclinic eddy activity, which lives off the potential energy stored in the sloping isopycnals, as well as the development of a Ferrel cell and storm track. For planets with larger surface heat capacity, we see a similar suppression, with the energy storage in the ocean surface, rather than atmospheric latent energy storage, primarily balancing the net energy loss during the winter months. These results suggest that, regardless of surface thermal inertia, water-covered high obliquity Earth-like planets would not experience significant extratropical storm activity and highlight the need for a proper characterization of polar properties in planetary modeling and observational investigations.", "date": "2022-08-09", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "publisher": "American Geophysical Union", "id_number": "CaltechAUTHORS:20220808-223832000", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220808-223832000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Davidow Discovery Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1029/2021jd036003", "primary_object": { "basename": "JGR_Atmospheres_-_2022_-_Lobo_-_The_Role_of_Water_Vapor_in_the_Response_of_the_Extratropical_Circulation_of_Earth\u2010like.pdf", "url": "https://authors.library.caltech.edu/records/3pp78-4rf19/files/JGR_Atmospheres_-_2022_-_Lobo_-_The_Role_of_Water_Vapor_in_the_Response_of_the_Extratropical_Circulation_of_Earth\u2010like.pdf" }, "pub_year": "2022", "author_list": "Lobo, Ana H. and Bordoni, Simona" }, { "id": "https://authors.library.caltech.edu/records/5p1y6-0r809", "eprint_status": "archive", "datestamp": "2025-11-14 23:51:29", "lastmod": "2025-11-21 02:44:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beaud-Flavien", "name": { "family": "Beaud", "given": "Flavien" }, "orcid": "0000-0002-0687-8741" }, { "id": "Aati-Saif", "name": { "family": "Aati", "given": "Saif" }, "orcid": "0000-0003-1087-832X" }, { "id": "Delaney-Ian", "name": { "family": "Delaney", "given": "Ian" }, "orcid": "0000-0003-1722-0600" }, { "id": "Adhikari-Surendra", "name": { "family": "Adhikari", "given": "Surendra" }, "orcid": "0000-0003-1021-6860" }, { "id": "Avouac-J-P", "name": { "family": "Avouac", "given": "Jean-Philippe" }, "orcid": "0000-0002-3060-8442" } ] }, "title": "Surge dynamics of Shisper Glacier revealed by time-series correlation of optical satellite images and their utility to substantiate a generalized sliding law", "ispublished": "pub", "full_text_status": "public", "note": "

© Author(s) 2022. This work is distributed under the Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union.

\n\n

The authors are very grateful for Shan Gremion's help in the early stages of the project. The authors would like to thank handling editor Nanna Bjørnholt Karlsson for their thoughtful input, as well as three anonymous reviewers and Douglas Benn for their constructive comments that helped to improve the manuscript. Flavien Beaud would like to thank Victor C. Tsai, Alex S. Gardner and many others for the joint Caltech–JPL group discussion on glacier sliding that greatly helped to formulate some of the ideas in this paper.

\n\n

This research has been supported by the Caltech-JPL President's and Director's Fund program and the Resnick Sustainability Institute, and the Swiss National Science Fund Mobility Postdoc Fellowships (grant no. P2SKP2_171755; 2017–2019 and P400P2_191105; 2020–2021).

\n\n

The code for image correlation is available here http://www.tectonics.caltech.edu/slip_history/spot_coseis/download_software.html (Leprince et al., 2007). The dataset and code used for the analysis and data plotting is available here https://doi.org/10.5281/zenodo.4624397 (Beaud et al., 2021).

\n\n

The supplement related to this article is available online at: https://doi.org/10.5194/tc-16-3123-2022-supplement.

\n\n

JPA initiated the project and coordinated the work. JPA and SuA generated the funding. FB identified the study site. FB, SaA, ID, SuA, and JPA framed the research and formulated the goals. SaA developed the remote-sensing methodology and processed the data. FB helped to validate the velocity maps. SaA generated preliminary figures presenting the remote-sensing analysis and results. FB analyzed the remote-sensing data and created figures for the manuscript. FB laid out the generalized sliding relationship, created the conceptual figures and conducted the assessment of the sliding relationship. JPA and SuA contributed to the remote-sensing analysis and the interpretation of the results. FB led the writing of the manuscript. ID assisted with interpreting the processes surrounding the glacier surge and preparing the manuscript. FB, SaA, ID, SuA, and JPA edited the manuscript.

\n\n

This paper was edited by Nanna Bjørnholt Karlsson and reviewed by Douglas Benn and three anonymous referees.

", "abstract": "

Understanding fast ice flow is key to assessing the future of glaciers. Fast ice flow is controlled by sliding at the bed, yet that sliding is poorly understood. A growing number of studies show the relationship between sliding and basal shear stress transitions from an initially rate-strengthening behavior to a rate-independent or rate-weakening behavior. Studies that have tested a glacier sliding law with data remain rare. Surging glaciers, as we show in this study, can be used as a natural laboratory to inform sliding laws because a single glacier shows extreme velocity variations at a subannual timescale. The present study has two main goals: (1) we introduce a new workflow to produce velocity maps with a high spatiotemporal resolution from remote-sensing data, combining Sentinel-2 (S2) and Landsat 8 (L8) and using the results to describe the recent surge of Shisper Glacier, and (2) we present a generalized sliding law and substantiate the sliding-law behavior using the remote sensing dataset. The quality and spatiotemporal resolution of the velocity time series allow us to identify a gradual amplification of spring speed-up velocities in the 2 years leading up to the surge that started in November 2017. We also find that surface velocity patterns during the surge can be decomposed into three main phases, and each phase appears to be associated with hydraulic changes. Using this dataset, we are able to highlight the rate-independent and rate-weakening relationships between resistive stress and sliding during the surge. We then discuss the importance of the generalized sliding relationship to reconcile observations of fast ice flow, and in particular, different surge behaviors. The approach used in this study remains qualitative, but if coupled with better bed-elevation data and numerical modeling could lead to the widespread quantification of sliding-law parameters.

", "date": "2022-08-03", "date_type": "published", "publication": "The Cryosphere", "volume": "16", "number": "8", "publisher": "European Geosciences Union", "pagerange": "3123-3148", "issn": "1994-0424", "official_url": "https://authors.library.caltech.edu/records/5p1y6-0r809", "funders": { "items": [ {}, {}, { "grant_number": "P2SKP2_171755" }, { "grant_number": "P400P2_191105" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Seismological-Laboratory" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/tc-16-3123-2022", "primary_object": { "basename": "tc-16-3123-2022.pdf", "url": "https://authors.library.caltech.edu/records/5p1y6-0r809/files/tc-16-3123-2022.pdf" }, "related_objects": [ { "basename": "tc-16-3123-2022-supplement.pdf", "url": "https://authors.library.caltech.edu/records/5p1y6-0r809/files/tc-16-3123-2022-supplement.pdf" } ], "pub_year": "2022", "author_list": "Beaud, Flavien; Aati, Saif; et al." }, { "id": "https://authors.library.caltech.edu/records/mjv6p-tz305", "eprint_id": 115869, "eprint_status": "archive", "datestamp": "2023-08-22 17:15:03", "lastmod": "2025-11-20 21:52:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chadwick-Austin-J", "name": { "family": "Chadwick", "given": "Austin J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Steele-Sarah", "name": { "family": "Steele", "given": "Sarah" }, "orcid": "0000-0002-7149-2693" }, { "id": "Silvestre-Jose", "name": { "family": "Silvestre", "given": "Jose" }, "orcid": "0000-0002-7747-893X" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "More extensive land loss expected on coastal deltas due to rivers jumping course during sea-level rise", "ispublished": "pub", "full_text_status": "public", "keywords": "land loss; sea-level rise; river deltas; river avulsions; river diversions; Multidisciplinary", "note": "\u00a9 2022 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). \n\nEdited by Andrea Rinaldo, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland; received October 22, 2021; accepted June 9, 2022.\n\nWe thank Vamsi Ganti for useful discussions and acknowledge NSF Grant EAR 1427262 and the Resnick Sustainability Institute at the California Institute of Technology for support. \n\nAuthor contributions:\nA.J.C. and M.P.L. designed research; A.J.C., S.S., J.S., and M.P.L. performed research; A.J.C., S.S., J.S., and M.P.L. analyzed data; and A.J.C., S.S., J.S., and M.P.L. wrote the paper.\n\nThe authors declare no competing interest.\n\nThis article is a PNAS Direct Submission. \n\nData Availability Statement. The data and MATLAB codes underlying this study are publicly available and were deposited in the SEAD Internal Repository (https://doi.org/10.26009/s0A0QNM6) (59).\n\n

Published - pnas.2119333119.pdf

Supplemental Material - pnas.2119333119.sapp.pdf

", "abstract": "River deltas are home to hundreds of millions of people worldwide and are in danger of sinking due to anthropogenic sea-level rise, land subsidence, and reduced sediment supply. Land loss is commonly forecast by averaging river sediment supply across the entire delta plain to assess whether deposition can keep pace with sea-level rise. However, land loss and deposition vary across the landscape because rivers periodically jump course, rerouting sediment to distinct subregions called delta lobes. Here, we developed a model to forecast land loss that resolves delta lobes and tested the model against a scaled laboratory experiment. Both the model and the experiment show that rivers build land on the active lobe, but the delta incurs gradual land loss on inactive lobes that are cut off from sediment after the river abandons course. The result is a band of terrain along the coast that is usually drowned but is nonetheless a sink for sediment when the lobe is active, leaving less of the total sediment supply available to maintain persistent dry land. Land loss is expected to be more extensive than predicted by classical delta-plain\u2013averaged models. Estimates for eight large deltas worldwide suggest that roughly half of the riverine sediment supply is delivered to terrain that undergoes long periods of submergence. These results draw the sustainability of deltas further into question and provide a framework to plan engineered diversions at a pace that will mitigate land loss in the face of rising sea levels.", "date": "2022-08-02", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "119", "number": "31", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2119333119", "id_number": "CaltechAUTHORS:20220726-998173000", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220726-998173000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2119333119", "pmcid": "PMC9351351", "primary_object": { "basename": "pnas.2119333119.pdf", "url": "https://authors.library.caltech.edu/records/mjv6p-tz305/files/pnas.2119333119.pdf" }, "related_objects": [ { "basename": "pnas.2119333119.sapp.pdf", "url": "https://authors.library.caltech.edu/records/mjv6p-tz305/files/pnas.2119333119.sapp.pdf" } ], "pub_year": "2022", "author_list": "Chadwick, Austin J.; Steele, Sarah; et al." }, { "id": "https://authors.library.caltech.edu/records/7ebct-w0d84", "eprint_id": 115555, "eprint_status": "archive", "datestamp": "2023-08-22 17:12:32", "lastmod": "2025-11-21 04:07:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Lee-Kyra-S", "name": { "family": "Lee", "given": "Kyra S." } }, { "id": "Yan-Ellen-X", "name": { "family": "Yan", "given": "Ellen X." }, "orcid": "0000-0003-3252-790X" }, { "id": "Thompson-Annelise-C", "name": { "family": "Thompson", "given": "Annelise C." }, "orcid": "0000-0003-2414-7050" }, { "id": "Morla-Maureen-B", "name": { "family": "Morla", "given": "Maureen B." }, "orcid": "0000-0002-2520-9543" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Demonstration of a Sensitive and Stable Chemical Gas Sensor Based on Covalently Functionalized MoS\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "Electron density, Functional groups, Functionalization, Sensors, Volatile organic compounds; General Materials Science; Biomedical Engineering; General Chemical Engineering", "note": "\u00a9 2022 American Chemical Society. \n\nReceived: April 26, 2022; Accepted: June 21, 2022; Published: July 13, 2022. \n\nThis work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under award no. DE-FG02-03-ER15483. XPS data and vapor sensor measurements were obtained using the facilities and support of the Molecular Materials Resource Center of the Beckman Institute of the California Institute of Technology. M.C.M. acknowledges Graduate Research Fellowship from the National Science Foundation. M.C.M. also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nAuthor Contributions: J.M.E., K.S.L., and E.X.Y. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - tz2c00372_si_001.pdf

", "abstract": "Chemically exfoliated MoS\u2082 was covalently functionalized and characterized as a chemically sensitive vapor sensor using changes in dc electrical resistance to detect a variety of volatile organic compounds (VOCs). Regardless of the polarity of the functionality introduced to the surface, sensors derived from functionalized MoS\u2082 showed high sensitivity for polar and nonpolar VOCs. Additionally, MoS\u2082 functionalized with trifluoromethyl benzyl bromide exhibited a very high sensitivity to polar and nonpolar organic vapors relative to the electrical resistance response of 2H MoS\u2082, 1T\u2032 MoS\u2082, or carbon black/polymer composite chemiresistive vapor sensors. Chemically functionalized MoS\u2082 sensors retained >70% of their initial responsiveness to test analytes after at least 72 h in air.", "date": "2022-08-01", "date_type": "published", "publication": "ACS Materials Letters", "volume": "4", "number": "8", "publisher": "American Chemical Society", "pagerange": "1475-1480", "id_number": "CaltechAUTHORS:20220714-369435000", "issn": "2639-4979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220714-369435000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03-ER15483" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsmaterialslett.2c00372", "primary_object": { "basename": "tz2c00372_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7ebct-w0d84/files/tz2c00372_si_001.pdf" }, "pub_year": "2022", "author_list": "Evans, Jake M.; Lee, Kyra S.; et al." }, { "id": "https://authors.library.caltech.edu/records/aqkfb-wnt10", "eprint_id": 117293, "eprint_status": "archive", "datestamp": "2023-08-20 08:19:34", "lastmod": "2025-11-21 01:18:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kaplan-David-E", "name": { "family": "Kaplan", "given": "David E." } }, { "id": "Mitridate-Andrea", "name": { "family": "Mitridate", "given": "Andrea" }, "orcid": "0000-0003-2898-5844" }, { "id": "Trickle-Tanner", "name": { "family": "Trickle", "given": "Tanner" }, "orcid": "0000-0003-1371-4988" } ] }, "title": "Constraining fundamental constant variations from ultralight dark matter with pulsar timing arrays", "ispublished": "pub", "full_text_status": "public", "note": "We thank Stephen Taylor for patiently helping us with enterprise, as well as giving valuable feedback on the manuscript. We also thank Jim Cordes for helpful comments, and Yufeng Du, Ryan Janish, and Vincent S.\u2009H. Lee for useful discussions. D.\u2009K. was supported by the National Science Foundation under Grant No. PHY-1818899. A.\u2009M. and T.\u2009T. were supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award No. DE-SC0021431, and the Quantum Information Science Enabled Discovery (QuantISED) for High Energy Physics (KA2401032). The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.", "abstract": "Pulsar timing arrays (PTAs) are exceptionally sensitive detectors in the frequency band nHz \u2272 f \u2272 \u03bcHz. Ultralight dark matter (ULDM), with mass in the range 10\u207b\u00b2\u00b3 eV \u2272 m_\u03d5 \u2272 10\u207b\u00b2\u2070 eV, is one class of DM models known to generate signals in this frequency window. While purely gravitational signatures of ULDM have been studied previously, in this work we consider two signals in PTAs which arise in the presence of direct couplings between ULDM and ordinary matter. These couplings induce variations in fundamental constants, i.e., particle masses and couplings. These variations can alter the moment of inertia of pulsars, inducing pulsar spin fluctuations via conservation of angular momentum, or induce apparent timing residuals due to reference clock shifts. By using mock data mimicking current PTA datasets, we show that PTA experiments outperform torsion balance and atomic clock constraints for ULDM coupled to electrons, muons, or gluons. In the case of coupling to quarks or photons, we find that PTAs and atomic clocks set similar constraints. Additionally, we discuss how future PTAs can further improve these constraints, and detail the unique properties of these signals relative to the previously studied effects of ULDM on PTAs.", "date": "2022-08-01", "date_type": "published", "publication": "Physical Review D", "volume": "106", "number": "3", "publisher": "American Physical Society", "pagerange": "Art. No. 035032", "id_number": "CaltechAUTHORS:20221010-454096500.7", "issn": "2470-0010", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221010-454096500.7", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1818899" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021431" }, { "agency": "Department of Energy (DOE)", "grant_number": "KA2401032" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.1103/physrevd.106.035032", "pub_year": "2022", "author_list": "Kaplan, David E.; Mitridate, Andrea; et al." }, { "id": "https://authors.library.caltech.edu/records/rb73g-vqz89", "eprint_id": 115341, "eprint_status": "archive", "datestamp": "2023-08-22 16:55:26", "lastmod": "2025-11-20 20:07:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Peterson-Elizabeth-A", "name": { "family": "Peterson", "given": "Elizabeth A." }, "orcid": "0000-0001-5379-3604" }, { "id": "Kumar-Rao-Karun", "name": { "family": "Rao", "given": "Karun K." }, "orcid": "0000-0001-6695-6046" }, { "id": "Lu-Yubing", "name": { "family": "Lu", "given": "Yubing" } }, { "id": "Li-Xiang", "name": { "family": "Li", "given": "Xiang" } }, { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Bauers-Sage-R", "name": { "family": "Bauers", "given": "Sage R." }, "orcid": "0000-0002-6505-5016" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Kan-Kevin-S", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Bajdich-Michal", "name": { "family": "Bajdich", "given": "Michal" }, "orcid": "0000-0003-1168-8616" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Addressing solar photochemistry durability with an amorphous nickel antimonate photoanode", "ispublished": "pub", "full_text_status": "public", "keywords": "solar fuels; oxygen evolution reaction; OER; amorphous; photoanode; nickel antimonate; photoelectrochemistry; high-throughput experimentation; X-ray absorption spectroscopy; electronic structure; pourbaix stability; General Physics and Astronomy; General Energy; General Engineering; General Materials Science; General Chemistry", "note": "\u00a9 2022 The Author(s). Under a Creative Commons license - Attribution 4.0 International (CC BY 4.0). \n\nReceived 23 March 2022, Revised 27 May 2022, Accepted 8 June 2022, Available online 27 June 2022. \n\nThis material is based on work performed by the Liquid Sunlight Alliance, which is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award DE-SC0021266. This research used computing resources from the Lawrencium computational cluster resource provided by the IT Division at the Lawrence Berkeley National Laboratory, supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract no. DE-AC02-05CH11231. Use of the Stanford Synchrotron Radiation Lightsource (beamlines 7-3 and 9-3), SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under contract no. DE-AC02-76SF00515. National Renewable Energy Laboratory is operated by the Alliance for Sustainable Energy, LLC, for the US Department of Energy (DOE) under contract no. DE-AC36-08GO28308. The Resnick Sustainability Institute at Caltech is also acknowledged for its support of enabling infrastructure and facilities. The views expressed in this article do not necessarily represent the views of the DOE or the US Government. \n\nAuthor contributions. L.Z. conducted synthesis and diffraction experiments with support from K.K. Electronic structure calculations were conducted by E.A.P. and J.B.N. The grand potential and Pourbaix phase diagrams were created by K.K.R. and M.B. Photoelectrochemistry experiments were conducted by Y.L. and Y.W. Optical spectroscopy measurements were conducted by P.F.N. X-ray absorption measurements were conducted by X.L. and analyzed by Y.L. under guidance from J.Y. Electronic structure experiments were conducted by M.H.R. Hall measurements were conducted by S.R.B. J.M.G. supervised the work, designed experiments, and coordinated manuscript writing along with L.Z. using contributions from all authors. \n\nData and code availability. Computational and experimental data are available at https://data.caltech.edu/records/20057 (10.22002/D1.20057). The code for processing experimental data is available at https://github.com/johnmgregoire/JCAPDataProcess. \n\nThe authors declare no competing interests.\n\n

Published - 1-s2.0-S2666386422002405-main.pdf

Supplemental Material - 1-s2.0-S2666386422002405-mmc1.pdf

", "abstract": "Renewable generation of fuels using solar energy is a promising technology whose deployment hinges on the discovery of materials with a combination of durability and solar-to-chemical conversion efficiency that has yet to be demonstrated. Stable operation of photoanodes has been demonstrated with wide-gap semiconductors, as well as protected visible gap semiconductors. Visible photoresponse from electrochemically stable materials is quite rare. In this paper, we report the high-throughput discovery of an amorphous Ni-Sb (1:1) oxide photoanode that meets the requirements of operational stability, visible photoresponse, and appreciable photovoltage. X-ray absorption characterization of Ni and Sb establishes a structural connection to rutile NiSb\u2082O\u2086, guiding electronic structure characterization via X-ray photoelectron experiments and density functional theory. This amorphous photoanode opens avenues for photoelectrode development due to the lack of crystal anisotropy combined with its operational stability, which mitigates the formation of an interphase that disrupts the semiconductor-electrolyte junction.", "date": "2022-07-20", "date_type": "published", "publication": "Cell Reports Physical Science", "volume": "3", "number": "7", "publisher": "Cell Press", "pagerange": "Art. No. 100959", "id_number": "CaltechAUTHORS:20220705-346693000", "issn": "2666-3864", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220705-346693000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.xcrp.2022.100959", "primary_object": { "basename": "1-s2.0-S2666386422002405-main.pdf", "url": "https://authors.library.caltech.edu/records/rb73g-vqz89/files/1-s2.0-S2666386422002405-main.pdf" }, "related_objects": [ { "basename": "1-s2.0-S2666386422002405-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/rb73g-vqz89/files/1-s2.0-S2666386422002405-mmc1.pdf" } ], "pub_year": "2022", "author_list": "Zhou, Lan; Peterson, Elizabeth A.; et al." }, { "id": "https://authors.library.caltech.edu/records/a4kf1-47t84", "eprint_id": 115648, "eprint_status": "archive", "datestamp": "2023-10-09 21:04:21", "lastmod": "2025-11-20 18:37:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dove-Lilian-A", "name": { "family": "Dove", "given": "Lilian A." }, "orcid": "0000-0001-8346-0034" }, { "id": "Balwada-Dhruv", "name": { "family": "Balwada", "given": "Dhruv" }, "orcid": "0000-0001-6632-0187" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "id": "Gray-Alison-R", "name": { "family": "Gray", "given": "Alison R." }, "orcid": "0000-0002-1644-7654" } ] }, "title": "Enhanced Ventilation in Energetic Regions of the Antarctic Circumpolar Current", "ispublished": "pub", "full_text_status": "public", "keywords": "General Earth and Planetary Sciences; Geophysics", "note": "\u00a9 2022. American Geophysical Union. \n\nIssue Online: 06 July 2022. Version of Record online: 06 July 2022. Accepted manuscript online: 25 June 2022. Manuscript accepted: 16 June 2022. Manuscript revised: 13 June 2022. Manuscript received: 22 December 2021. \n\nL. A. Dove and A. F. Thompson acknowledge funding from National Science Foundation (NSF) award OCE-1756956, the David and Lucille Packard Foundation, and the Resnick Sustainability Institute. L. A. Dove was additionally supported by an NSF Graduate Research Fellowship. D. Balwada and A. R. Gray were supported by NSF Award OCE-1756882. A. R. Gray acknowledges additional funding through National Oceanic and Atmospheric Administration Award NA20OAR4320271 and through NSF's Southern Ocean Carbon and Climate Observations and Modeling Project under Awards PLR-1425989 and OPP-1936222. The authors are grateful for the comments of three anonymous reviewers, which led to the improvement of this manuscript. \n\nData Availability Statement. The float data were collected and made freely available by the International Argo Program and the national programs that contribute to it (https://argo.ucsd.edu, https://www.ocean-ops.org). The Argo Program is part of the Global Ocean Observing System. The float profiles used in this manuscript are available in the Argo Global Data Assembly Center 10 June 2021 screenshot (https://doi.org/10.17882/42182%2385023). Sea level anomaly products were produced and distributed by the Copernicus Marine 360 and Environment Monitoring Service and are available at https://resources.marine.copernicus.eu/product-detail/SEALEVEL_GLO_PHY_L4_MY_008_047/INFORMATION. Finite-size Lyapunov Exponents were produced and distributed by AVISO+ and are available at https://www.aviso.altimetry.fr/en/data/products/value-added-products/fsle-finite-size-lyapunov-exponents.html\n\n

Published - 2021GL097574.pdf

Accepted Version - 2021GL097574-acc.pdf

Supplemental Material - 2021gl097574-sup-0001-supporting_information_si-s01.pdf

", "abstract": "Flow-topography interactions along the path of the Antarctic Circumpolar Current generate standing meanders, create regions of enhanced eddy kinetic energy (EKE), and modify frontal structure. We consider the impact of standing meanders on ventilation based on oxygen measurements from Argo floats and the patterns of apparent oxygen utilization (AOU). Regions of high-EKE have relatively reduced AOU values at depths 200\u2013700 m below the base of the mixed layer and larger AOU variance, suggesting enhanced ventilation due to both along-isopycnal stirring and enhanced exchange across the base of the mixed layer. Vertical exchange is inferred from finite-size Lyapunov exponents, a proxy for the magnitude of surface lateral density gradients, which suggest that submesoscale vertical velocities may contribute to ventilation. The shaping of ventilation by standing meanders has implications for the temporal and spatial variability of air\u2012sea exchange.", "date": "2022-07-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "49", "number": "13", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021GL097574", "id_number": "CaltechAUTHORS:20220715-744273000", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220715-744273000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OCE-1756956" }, { "agency": "David and Lucile Packard Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "NSF", "grant_number": "OCE-1756882" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA20OAR4320271" }, { "agency": "NSF", "grant_number": "PLR-1425989" }, { "agency": "NSF", "grant_number": "OPP-1936222" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021gl097574", "primary_object": { "basename": "2021GL097574-acc.pdf", "url": "https://authors.library.caltech.edu/records/a4kf1-47t84/files/2021GL097574-acc.pdf" }, "related_objects": [ { "basename": "2021GL097574.pdf", "url": "https://authors.library.caltech.edu/records/a4kf1-47t84/files/2021GL097574.pdf" }, { "basename": "2021gl097574-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/a4kf1-47t84/files/2021gl097574-sup-0001-supporting_information_si-s01.pdf" } ], "pub_year": "2022", "author_list": "Dove, Lilian A.; Balwada, Dhruv; et al." }, { "id": "https://authors.library.caltech.edu/records/ejckz-5d840", "eprint_id": 115474, "eprint_status": "archive", "datestamp": "2023-08-22 16:47:12", "lastmod": "2025-11-20 22:40:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tribby-Ariana-L", "name": { "family": "Tribby", "given": "Ariana L." }, "orcid": "0000-0002-6435-4575" }, { "id": "Bois-J-S", "name": { "family": "Bois", "given": "Justin S." }, "orcid": "0000-0001-7137-8746" }, { "id": "Montzka-Stephen-A", "name": { "family": "Montzka", "given": "Stephen A." }, "orcid": "0000-0002-9396-0400" }, { "id": "Atlas-Elliot-L", "name": { "family": "Atlas", "given": "Elliot L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Vimont-Isaac", "name": { "family": "Vimont", "given": "Isaac" }, "orcid": "0000-0002-0740-4927" }, { "id": "Lan-Xin", "name": { "family": "Lan", "given": "Xin" } }, { "id": "Tans-Pieter-P", "name": { "family": "Tans", "given": "Pieter P." }, "orcid": "0000-0002-9883-0787" }, { "id": "Elkins-James-W", "name": { "family": "Elkins", "given": "James W." }, "orcid": "0000-0003-4701-3100" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Hydrocarbon Tracers Suggest Methane Emissions from Fossil Sources Occur Predominately Before Gas Processing and That Petroleum Plays Are a Significant Source", "ispublished": "pub", "full_text_status": "public", "keywords": "ethane; propane; natural gas; methane; energy; Environmental Chemistry; General Chemistry", "note": "\u00a9 2022 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).\n\nReceived 11 February 2022. Accepted 18 May 2022. Revised 18 May 2022. Published online 14 June 2022. Published in issue 5 July 2022. \n\nThis work was supported by the Resnick Sustainability Institute, including computations conducted in the Resnick High Performance Computing Center. A.L.T. received funding from NSF Award No. DGE-1745301. NOAA support was provided for HIPPO by NSF Award No. AGS-0628452; California Institute of Technology support for ATom was provided by NASA Grant Award No. NNX15AG61A. NOAA support for ATom was provided by NASA EVS2 Award No. NNH17AE26I; additional support was provided by NASA Upper Atmosphere Research Program award No. NNH13AV69I. NOAA laboratory and salary support is from NOAA Climate Change Program. S.A.M. acknowledges funding in part from NOAA Climate Program Office's AC4 Program. NOAA flask sampling and technical support was provided by Dr. Fred Moore of NOAA/CIRES. Additional technical support was provided by C. Siso, B. Miller, M. Crotwell, C. Sweeney, A. Andrews, J. Higgs, D. Neff, J. Kofler, K. McKain, M. Madronich, P. Handley, and S. Wolter. We thank IHS Markit for providing PointLogic economic data. \n\nThe authors declare no competing financial interest.\n\n

Published - acs.est.2c00927.pdf

Supplemental Material - es2c00927_si_001.pdf

", "abstract": "We use global airborne observations of propane (C\u2083H\u2088) and ethane (C\u2082H\u2086) from the Atmospheric Tomography (ATom) and HIAPER Pole-to-Pole Observations (HIPPO), as well as U.S.-based aircraft and tower observations by NOAA and from the NCAR FRAPPE campaign as tracers for emissions from oil and gas operations. To simulate global mole fraction fields for these gases, we update the default emissions' configuration of C\u2083H\u2088 used by the global chemical transport model, GEOS-Chem v13.0.0, using a scaled C\u2082H\u2086 spatial proxy. With the updated emissions, simulations of both C\u2083H\u2088 and C\u2082H\u2086 using GEOS-Chem are in reasonable agreement with ATom and HIPPO observations, though the updated emission fields underestimate C\u2083H\u2088 accumulation in the arctic wintertime, pointing to additional sources of this gas in the high latitudes (e.g., Europe). Using a Bayesian hierarchical model, we estimate global emissions of C\u2082H\u2086 and C\u2083H\u2088 from fossil fuel production in 2016\u20132018 to be 13.3 \u00b1 0.7 (95% CI) and 14.7 \u00b1 0.8 (95% CI) Tg/year, respectively. We calculate bottom-up hydrocarbon emission ratios using basin composition measurements weighted by gas production and find their magnitude is higher than expected and is similar to ratios informed by our revised alkane emissions. This suggests that emissions are dominated by pre-processing activities in oil-producing basins.", "date": "2022-07-05", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "56", "number": "13", "publisher": "American Chemical Society", "pagerange": "9623-9631", "id_number": "CaltechAUTHORS:20220711-653341000", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220711-653341000", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "AGS-0628452" }, { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NASA", "grant_number": "NNH17AE261" }, { "agency": "NASA", "grant_number": "NNH13AV69I" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1021/acs.est.2c00927", "pmcid": "PMC9260955", "primary_object": { "basename": "acs.est.2c00927.pdf", "url": "https://authors.library.caltech.edu/records/ejckz-5d840/files/acs.est.2c00927.pdf" }, "related_objects": [ { "basename": "es2c00927_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ejckz-5d840/files/es2c00927_si_001.pdf" } ], "pub_year": "2022", "author_list": "Tribby, Ariana L.; Bois, Justin S.; et al." }, { "id": "https://authors.library.caltech.edu/records/yjw8x-3cw47", "eprint_id": 117075, "eprint_status": "archive", "datestamp": "2023-08-22 16:45:31", "lastmod": "2025-11-20 23:46:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Alinia-Bahram", "name": { "family": "Alinia", "given": "Bahram" }, "orcid": "0000-0002-2974-6645" }, { "id": "Hajiesmaili-Mohammad-H", "name": { "family": "Hajiesmaili", "given": "Mohammad H." } }, { "id": "Lee-Zachary-J", "name": { "family": "Lee", "given": "Zachary J." }, "orcid": "0000-0002-5358-2388" }, { "id": "Crespi-Noel", "name": { "family": "Crespi", "given": "Noel" }, "orcid": "0000-0003-2962-192X" }, { "id": "Mallada-Enrique", "name": { "family": "Mallada", "given": "Enrique" }, "orcid": "0000-0003-1568-1833" } ] }, "title": "Online EV Scheduling Algorithms for Adaptive Charging Networks with Global Peak Constraints", "ispublished": "pub", "full_text_status": "public", "keywords": "Computational Theory and Mathematics; Control and Optimization; Hardware and Architecture; Renewable Energy, Sustainability and the Environment; Software", "note": "The work of Mohammad H. Hajiesmaili was supported by NSF through grant CNS 1908298. The work of Zachary J. Lee was supported by the NSF Graduate Research Fellowship Program (Grant No. 1745301) and Resnick Sustainability Institute. Enrique Mallada is supported by ARO through contract W911NF-17-1-0092, US DoE EERE Award DE-EE0008006, and NSF through Grants CNS 1544771, EPCN 1711188, AMPS 1736448, and CAREER 1752362.", "abstract": "This paper tackles online scheduling of electric vehicles (EVs) in an adaptive charging network (ACN) with local and global peak constraints. Given the aggregate charging demand of the EVs and the peak constraints of the ACN, it might be infeasible to fully charge all the EVs according to their charging demand. Two alternatives in such resource-limited scenarios are to maximize the social welfare by partially charging the EVs (fractional model) or selecting a subset of EVs and fully charge them (integral model). The technical challenge is the need for online solution design since in practical scenarios the scheduler has no or limited information of future arrivals in a time-coupled underlying problem. For the fractional model, we devise both offline and online algorithms. We prove that the offline algorithm is optimal. Using competitive ratio as the performance measure, we prove the online algorithm achieves a competitive ratio of 2. The integral model, however, is more challenging since the underlying problem is strongly NP-hard due to 0/1 selection criteria of EVs. Hence, efficient solution design is challenging even in offline setting. For offline setting, we devise a low-complexity primal-dual scheduling algorithm that achieves a bounded approximation ratio. Built upon the offline approximate algorithm, we propose an online algorithm and analyze its competitive ratio in special cases. Extensive trace-driven experimental results show that the performance of the proposed online algorithms is close to the offline optimum, and outperform the existing solutions.", "date": "2022-07-01", "date_type": "published", "publication": "IEEE Transactions on Sustainable Computing", "volume": "7", "number": "3", "publisher": "Institute of Electrical and Electronics Engineers", "pagerange": "537-548", "id_number": "CaltechAUTHORS:20220919-447854900", "issn": "2377-3782", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220919-447854900", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-1908298" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0092" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0008006" }, { "agency": "NSF", "grant_number": "CNS-1544771" }, { "agency": "NSF", "grant_number": "ECCS-1711188" }, { "agency": "NSF", "grant_number": "DMS-1736448" }, { "agency": "NSF", "grant_number": "ECCS-1752362" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/tsusc.2020.2979854", "pub_year": "2022", "author_list": "Alinia, Bahram; Hajiesmaili, Mohammad H.; et al." }, { "id": "https://authors.library.caltech.edu/records/ecckn-yg533", "eprint_id": 113991, "eprint_status": "archive", "datestamp": "2023-08-20 08:08:27", "lastmod": "2025-11-21 02:08:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Hsiao-Yi", "name": { "family": "Chen", "given": "Hsiao-Yi" }, "orcid": "0000-0003-1962-5767" }, { "id": "Mitridate-Andrea", "name": { "family": "Mitridate", "given": "Andrea" }, "orcid": "0000-0003-2898-5844" }, { "id": "Trickle-Tanner", "name": { "family": "Trickle", "given": "Tanner" }, "orcid": "0000-0003-1371-4988" }, { "id": "Zhang-Zhengkang", "name": { "family": "Zhang", "given": "Zhengkang" }, "orcid": "0000-0001-8305-5581" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" }, { "id": "Zurek-K-M", "name": { "family": "Zurek", "given": "Kathryn M." }, "orcid": "0000-0002-2629-337X" } ] }, "title": "Dark matter direct detection in materials with spin-orbit coupling", "ispublished": "pub", "full_text_status": "public", "note": "Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. \n\nFunded by SCOAP3.\n\nReceived 15 March 2022; accepted 13 July 2022; published 25 July 2022. \n\nH.-Y.\u2009C. and M.\u2009B. were supported by the National Science Foundation under Grant No. DMR-1750613. A.\u2009M., T.\u2009T., K.\u2009Z., and Z.\u2009Z. were supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics, under Award No. DE-SC0021431, and the Quantum Information Science Enabled Discovery (QuantISED) for High Energy Physics (KA2401032). K.\u2009Z. was also supported by a Simons Investigator Award. Z.\u2009Z. was also supported by the U.S. Department of Energy under the Grant No. DE-SC0011702. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.\n\n

Published - PhysRevD.106.015024.pdf

Submitted - 2202.11716.pdf

", "abstract": "Semiconductors with O(meV) band gaps have been shown to be promising targets to search for sub-MeV mass dark matter (DM). In this paper we focus on a class of materials where such narrow band gaps arise naturally as a consequence of spin-orbit coupling (SOC). Specifically, we are interested in computing DM-electron scattering and absorption rates in these materials using state-of-the-art density functional theory techniques. To do this, we extend the DM interaction rate calculation to include SOC effects which necessitates a generalization to spin-dependent wave functions. We apply our new formalism to calculate limits for several DM benchmark models using an example ZrTe\u2085 target and show that the inclusion of SOC can substantially alter projected constraints.", "date": "2022-07-01", "date_type": "published", "publication": "Physical Review D", "volume": "106", "number": "1", "publisher": "American Physical Society", "pagerange": "Art. No. 015024", "id_number": "CaltechAUTHORS:20220322-205046206", "issn": "2470-0010", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220322-205046206", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021431" }, { "agency": "Department of Energy (DOE)", "grant_number": "KA2401032" }, { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011702" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "SCOAP3" } ] }, "other_numbering_system": { "items": [ { "id": "2022-007", "name": "CALT-TH" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Walter-Burke-Institute-for-Theoretical-Physics" } ] }, "doi": "10.1103/PhysRevD.106.015024", "primary_object": { "basename": "2202.11716.pdf", "url": "https://authors.library.caltech.edu/records/ecckn-yg533/files/2202.11716.pdf" }, "related_objects": [ { "basename": "PhysRevD.106.015024.pdf", "url": "https://authors.library.caltech.edu/records/ecckn-yg533/files/PhysRevD.106.015024.pdf" } ], "pub_year": "2022", "author_list": "Chen, Hsiao-Yi; Mitridate, Andrea; et al." }, { "id": "https://authors.library.caltech.edu/records/wad42-aaa58", "eprint_id": 115658, "eprint_status": "archive", "datestamp": "2023-10-09 21:05:02", "lastmod": "2025-11-21 03:36:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chadwick-Austin-J", "name": { "family": "Chadwick", "given": "A. J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Steele-Sarah", "name": { "family": "Steele", "given": "S." }, "orcid": "0000-0002-7149-2693" }, { "id": "Silvestre-Jose", "name": { "family": "Silvestre", "given": "J." }, "orcid": "0000-0002-7747-893X" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "M. P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Effect of Sea\u2010Level Change on River Avulsions and Stratigraphy for an Experimental Lowland Delta", "ispublished": "pub", "full_text_status": "public", "keywords": "river deltas; sea-level rise; river avulsions; delta stratigraphy; geomorphology; sedimentology; Earth-Surface Processes; Geophysics", "note": "\u00a9 2022. American Geophysical Union. \n\nIssue Online: 14 July 2022. Version of Record online: 14 July 2022. Accepted manuscript online: 02 July 2022. Manuscript accepted: 24 June 2022. Manuscript revised: 15 June 2022. Manuscript received: 07 September 2021. \n\nWe thank Brian Fuller, Tom Ulizio, and Kirby Sikes for assistance in conducting the experiment, and thank Maarten G. Kleinhans, Wonsuck Kim, and Katherine Ratliff for constructive reviews. We acknowledge NSF Grant EAR 1427262 and the Resnick Sustainability Institute at the California Institute of Technology for support. \n\nData Availability Statement. The data underlying this study are publicly available in the SEAD repository at http://doi.org/10.26009/s0FD85I6 (Chadwick, 2022). Analysis was performed and figures were made using MATLAB R2021b software available at www.mathworks.com (MATLAB, 2021). \n\nThe authors declare no conflicts of interest relevant to this study.\n\n

Published - 2021JF006422.pdf

Accepted Version - 2021JF006422-acc.pdf

Supplemental Material - 2021jf006422-sup-0001-supporting_information_si-s01.pdf

Supplemental Material - 2021jf006422-sup-0002-table_si-s01.xlsx

Supplemental Material - 2021jf006422-sup-0003-movie_si-s01.mp4

", "abstract": "Lowland deltas experience natural diversions in river course known as avulsions. River avulsions pose catastrophic flood hazards and redistribute sediment that is vital for sustaining land in the face of sea-level rise. Avulsions also affect deltaic stratigraphic architecture and the preservation of sea-level cycles in the sedimentary record. Here, we present results from an experimental lowland delta with persistent backwater effects and systematic changes in the rates of sea-level rise and fall. River avulsions repeatedly occurred where and when the river aggraded to a height of nearly half the channel depth, giving rise to a preferential avulsion node within the backwater zone regardless of sea-level change. As sea-level rise accelerated, the river responded by avulsing more frequently until reaching a maximum frequency limited by the upstream sediment supply. Experimental results support recent models, field observations, and experiments, and suggest anthropogenic sea-level rise will introduce more frequent avulsion hazards farther inland than observed in recent history. The experiment also demonstrated that avulsions can occur during sea-level fall\u2014even within the confines of an incised valley\u2014provided the offshore basin is shallow enough to allow the shoreline to prograde and the river to aggrade. Avulsions create erosional surfaces within stratigraphy that bound beds reflecting the amount of deposition between avulsions. Avulsion-induced scours overprint erosional surfaces from sea-level fall, except when the cumulative drop in sea-level is greater than the channel depth and less than the basin depth. Results imply sea-level signals outside this range are removed or distorted in delta deposits.", "date": "2022-07", "date_type": "published", "publication": "Journal of Geophysical Research. Earth Surface", "volume": "127", "number": "7", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021JF006422", "id_number": "CaltechAUTHORS:20220715-744506000", "issn": "2169-9003", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220715-744506000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021jf006422", "primary_object": { "basename": "2021JF006422.pdf", "url": "https://authors.library.caltech.edu/records/wad42-aaa58/files/2021JF006422.pdf" }, "related_objects": [ { "basename": "2021jf006422-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/wad42-aaa58/files/2021jf006422-sup-0001-supporting_information_si-s01.pdf" }, { "basename": "2021jf006422-sup-0002-table_si-s01.xlsx", "url": "https://authors.library.caltech.edu/records/wad42-aaa58/files/2021jf006422-sup-0002-table_si-s01.xlsx" }, { "basename": "2021jf006422-sup-0003-movie_si-s01.mp4", "url": "https://authors.library.caltech.edu/records/wad42-aaa58/files/2021jf006422-sup-0003-movie_si-s01.mp4" }, { "basename": "2021JF006422-acc.pdf", "url": "https://authors.library.caltech.edu/records/wad42-aaa58/files/2021JF006422-acc.pdf" } ], "pub_year": "2022", "author_list": "Chadwick, A. J.; Steele, S.; et al." }, { "id": "https://authors.library.caltech.edu/records/1mttm-4w433", "eprint_id": 113762, "eprint_status": "archive", "datestamp": "2023-08-22 16:26:06", "lastmod": "2025-11-20 23:42:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Xin", "name": { "family": "Chen", "given": "Xin" }, "orcid": "0000-0002-0952-0008" }, { "id": "Qu-Guannan", "name": { "family": "Qu", "given": "Guannan" }, "orcid": "0000-0002-5466-3550" }, { "id": "Tang-Yujie", "name": { "family": "Tang", "given": "Yujie" }, "orcid": "0000-0002-4921-8372" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven" }, "orcid": "0000-0001-6476-3048" }, { "id": "Li-Na", "name": { "family": "Li", "given": "Na" }, "orcid": "0000-0001-9545-3050" } ] }, "title": "Reinforcement Learning for Selective Key Applications in Power Systems: Recent Advances and Future Challenges", "ispublished": "pub", "full_text_status": "public", "keywords": "Frequency regulation, voltage control, energy management, reinforcement learning, smart grid; General Computer Science", "note": "\u00a9 2022 IEEE. \n\nManuscript received February 9, 2021; revised July 27, 2021 and November 17, 2021; accepted February 18, 2022. Date of publication February 25, 2022; date of current version June 21, 2022. \n\nThis work was supported in part by NSF CAREER under Grant ECCS-1553407; in part by the NSF AI Institute under Grant 2112085; in part by NSF under Grant ECCS-1931662, Grant AitF- 1637598, and Grant CNS-1518941; in part by Cyber-Physical Systems (CPS) under Grant ECCS-1932611; in part by Resnick Sustainability Institute; in part by PIMCO Fellowship; in part by Amazon AI4Science Fellowship; and in part by the Caltech Center for Autonomous Systems and Technologies (CAST). Paper no. TSG-00195-2021.\n\n

Accepted Version - 2102.01168.pdf

", "abstract": "With large-scale integration of renewable generation and distributed energy resources, modern power systems are confronted with new operational challenges, such as growing complexity, increasing uncertainty, and aggravating volatility. Meanwhile, more and more data are becoming available owing to the widespread deployment of smart meters, smart sensors, and upgraded communication networks. As a result, data-driven control techniques, especially reinforcement learning (RL), have attracted surging attention in recent years. This paper provides a comprehensive review of various RL techniques and how they can be applied to decision-making and control in power systems. In particular, we select three key applications, i.e., frequency regulation, voltage control, and energy management, as examples to illustrate RL-based models and solutions. We then present the critical issues in the application of RL, i.e., safety, robustness, scalability, and data. Several potential future directions are discussed as well.", "date": "2022-07", "date_type": "published", "publication": "IEEE Transactions on Smart Grid", "volume": "13", "number": "4", "publisher": "IEEE", "pagerange": "2935-2958", "id_number": "CaltechAUTHORS:20220307-188369000", "issn": "1949-3053", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220307-188369000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ECCS-1553407" }, { "agency": "NSF", "grant_number": "CBET-2112085" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "CNS-1518941" }, { "agency": "NSF", "grant_number": "ECCS-1932611" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "PIMCO" }, { "agency": "Amazon AI4Science Fellowship" }, { "agency": "Center for Autonomous Systems and Technologies" } ] }, "local_group": { "items": [ { "id": "Center-for-Autonomous-Systems-and-Technologies-(CAST)" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/tsg.2022.3154718", "primary_object": { "basename": "2102.01168.pdf", "url": "https://authors.library.caltech.edu/records/1mttm-4w433/files/2102.01168.pdf" }, "pub_year": "2022", "author_list": "Chen, Xin; Qu, Guannan; et al." }, { "id": "https://authors.library.caltech.edu/records/53fe0-48m74", "eprint_id": 113697, "eprint_status": "archive", "datestamp": "2023-08-22 15:49:29", "lastmod": "2025-11-20 19:07:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Park-Jihyun", "name": { "family": "Park", "given": "Jihyun" }, "orcid": "0000-0002-1926-3607" }, { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" }, { "id": "Cheung-Lily-S", "name": { "family": "Cheung", "given": "Lily S." }, "orcid": "0000-0001-8089-7783" } ] }, "title": "Toolboxes for plant systems biology research", "ispublished": "pub", "full_text_status": "public", "keywords": "Biomedical Engineering; Bioengineering; Biotechnology", "note": "\u00a9 2022 The Author(s). Published by Elsevier Under a Creative Commons license - Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).\n\nAvailable online 7 February 2022, Version of Record 7 February 2022. \n\nL.S.C. was supported by National Science Foundation grant 1942722 and G.S.D. was supported by the Resnick Sustainability Institute Postdoctoral Fellowship. Figures were created with BioRender.com. \n\nCRediT authorship contribution statement. Jihyun Park: Writing \u2013 review & editing. Gozde S Demirer: Writing \u2013 review & editing. Lily S Cheung: Writing \u2013 review & editing.\n\n

Published - 1-s2.0-S095816692200012X-main.pdf

", "abstract": "The terms 'systems' and 'synthetic biology' are often used together, with most scientists striding between the two fields rather than adhering to a single side. Often too, scientists want to understand a system to inform the design of gene circuits that could endow it with new functions. However, this does not need to be the progression of research, as synthetic constructs can help improve our understanding of a system. Here, we review synthetic biology tool kits with the potential to overcome pleiotropic effects, compensatory mechanisms, and redundancy in plants. Combined with -omics techniques, these tools could reveal novel insights on plant growth and development, an aim that has gained renewed urgency given the impact of climate change on crop productivity.", "date": "2022-06", "date_type": "published", "publication": "Current Opinion in Biotechnology", "volume": "75", "publisher": "Elsevier", "pagerange": "Art. No. 102692", "id_number": "CaltechAUTHORS:20220302-323788000", "issn": "0958-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220302-323788000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1942722" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.copbio.2022.102692", "primary_object": { "basename": "1-s2.0-S095816692200012X-main.pdf", "url": "https://authors.library.caltech.edu/records/53fe0-48m74/files/1-s2.0-S095816692200012X-main.pdf" }, "pub_year": "2022", "author_list": "Park, Jihyun; Demirer, Gozde S.; et al." }, { "id": "https://authors.library.caltech.edu/records/908rx-de455", "eprint_id": 114959, "eprint_status": "archive", "datestamp": "2023-08-22 15:44:49", "lastmod": "2025-11-21 01:06:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brooke-Sam-A-S", "name": { "family": "Brooke", "given": "Sam" }, "orcid": "0000-0002-9063-0609" }, { "id": "Chadwick-Austin-J", "name": { "family": "Chadwick", "given": "Austin J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Silvestre-Jose", "name": { "family": "Silvestre", "given": "Jose" }, "orcid": "0000-0002-7747-893X" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" }, { "id": "Edmonds-Douglas-A", "name": { "family": "Edmonds", "given": "Douglas A." }, "orcid": "0000-0003-0161-1754" }, { "id": "Ganti-Vamsi", "name": { "family": "Ganti", "given": "Vamsi" }, "orcid": "0000-0003-2165-6052" } ] }, "title": "Where rivers jump course", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2022 the authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original US government works. https://www.sciencemag.org/about/science-licenses-journal-article-reuse. \n\nSubmitted 26 August 2021; accepted 1 April 2022. \n\nWe thank S. Cohen for sharing the water and sediment data and P. Passalacqua and two anonymous reviewers for constructive comments on a previous version of the manuscript. \n\nThis work was supported by the National Science Foundation EAR 1935669 (to V.G.) and EAR 1427262 (to M.P.L.). A.J.C. was supported by the Caltech Resnick Sustainability Institute. \n\nAuthor contributions: Conceptualization: V.G., S.B., M.P.L., and A.J.C. Methodology: S.B., V.G., J.S., A.J.C., and D.E. Investigation: S.B., V.G., J.S., A.J.C., and M.P.L. Visualization: S.B. and V.G. Funding acquisition: V.G. and M.P.L. Project administration: V.G. Supervision: V.G. and M.P.L. Writing \u2013 original draft: V.G., S.B., and M.P.L. Writing \u2013 review and editing: V.G., S.B., M.P.L., A.J.C., J.S., and D.E. \n\nThe authors declare that they have no competing interests. \n\nData and materials availability: The data analyzed in this study are tabulated in the supplementary materials. The satellite imagery analyzed here is publicly available, with USGS/NASA Landsat satellite imagery and SRTM 1 arcsec elevation data downloaded from the USGS Earth Explorer.\n\n

Supplemental Material - science.abm1215_movies_s1_and_s2.zip

Supplemental Material - science.abm1215_sm.pdf

Supplemental Material - science.abm1215_table_s1.zip

", "abstract": "Rivers can abruptly shift pathways in rare events called avulsions, which cause devastating floods. The controls on avulsion locations are poorly understood as a result of sparse data on such features. We analyzed nearly 50 years of satellite imagery and documented 113 avulsions across the globe that indicate three distinct controls on avulsion location. Avulsions on fans coincide with valley-confinement change, whereas avulsions on deltas are primarily clustered within the backwater zone, indicating a control by spatial flow deceleration or acceleration during floods. However, 38% of avulsions on deltas occurred upstream of backwater effects. These events occurred in steep, sediment-rich rivers in tropical and desert environments. Our results indicate that avulsion location on deltas is set by the upstream extent of flood-driven erosion, which is typically limited to the backwater zone but can extend far upstream in steep, sediment-laden rivers. Our findings elucidate how avulsion hazards might respond to land use and climate change.", "date": "2022-05-26", "date_type": "published", "publication": "Science", "volume": "376", "number": "6596", "publisher": "American Association for the Advancement of Science", "pagerange": "987-990", "id_number": "CaltechAUTHORS:20220531-912112300", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220531-912112300", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1935669" }, { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.abm1215", "primary_object": { "basename": "science.abm1215_movies_s1_and_s2.zip", "url": "https://authors.library.caltech.edu/records/908rx-de455/files/science.abm1215_movies_s1_and_s2.zip" }, "related_objects": [ { "basename": "science.abm1215_sm.pdf", "url": "https://authors.library.caltech.edu/records/908rx-de455/files/science.abm1215_sm.pdf" }, { "basename": "science.abm1215_table_s1.zip", "url": "https://authors.library.caltech.edu/records/908rx-de455/files/science.abm1215_table_s1.zip" } ], "pub_year": "2022", "author_list": "Brooke, Sam; Chadwick, Austin J.; et al." }, { "id": "https://authors.library.caltech.edu/records/s6z1q-7pv61", "eprint_id": 114863, "eprint_status": "archive", "datestamp": "2023-08-22 15:34:37", "lastmod": "2025-11-20 22:39:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Douglas-Madison-M", "name": { "family": "Douglas", "given": "Madison M." }, "orcid": "0000-0002-0762-4719" }, { "id": "Li-Gen-K", "name": { "family": "Li", "given": "Gen K." }, "orcid": "0000-0002-6300-3570" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Rowland-Joel-C", "name": { "family": "Rowland", "given": "Joel C." }, "orcid": "0000-0001-6308-8976" }, { "id": "Kemeny-Preston-C", "name": { "family": "Kemeny", "given": "Preston C." }, "orcid": "0000-0003-1693-4142" }, { "id": "West-A-Joshua", "name": { "family": "West", "given": "A. Joshua" }, "orcid": "0000-0001-6909-1471" }, { "id": "Schwenk-Jon", "name": { "family": "Schwenk", "given": "Jon" }, "orcid": "0000-0001-5803-9686" }, { "id": "Piliouras-Anastasia-P", "name": { "family": "Piliouras", "given": "Anastasia P." }, "orcid": "0000-0002-6336-0762" }, { "id": "Chadwick-Austin-J", "name": { "family": "Chadwick", "given": "Austin J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Organic carbon burial by river meandering partially offsets bank erosion carbon fluxes in a discontinuous permafrost floodplain", "ispublished": "pub", "full_text_status": "public", "keywords": "Earth-Surface Processes; Geophysics", "note": "\u00a9 Author(s) 2022. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 15 Oct 2021 \u2013 Discussion started: 03 Nov 2021 \u2013 Revised: 18 Mar 2022 \u2013 Accepted: 12 Apr 2022 \u2013 Published: 10 May 2022. \n\nWe thank the Koyukuk-hotana Athabascans of Huslia, First Chief Norman Burgett, and the Huslia Tribal Council for land access and US Fish and Wildlife Service (USFWS) \u2013 Koyukuk National Wildlife refuge for research permitting and logistical assistance. Shawn Huffman, Alvin Attla, and Virgil Umphenour provided field support and local expertise. We also thank Alex Sessions and Fenfang Wu for use of equipment and assistance with preparing samples for TOC analysis and Matthew Kirby for use of the Malvern Mastersizer and assistance with grain size analysis. \n\nWe acknowledge financial support from the Department of Energy Office of Science, Biological and Environmental Research, Earth and Environmental Systems Sciences Division, Subsurface Biogeochemical Research Program Early Career Award to Joel C. Rowland; Caltech Terrestrial Hazards Observation and Reporting Center, Foster and Coco Stanback, the Linde Family, and the Resnick Sustainability Institute to Michael P. Lamb and Woodward W. Fischer; the Caltech Center for Environmental Microbial Interactions to Woodward W. Fischer; National Science Foundation Awards 2127442 and 2031532; the National Defence Science and Engineering Graduate Fellowship for Madison M. Douglas and Preston C. Kemeny; and the Fannie and John Hertz Foundation Cohen/Jacobs and Stein Family Fellowship for Preston C. Kemeny. \n\nAuthor contributions. MPL, JCR, WWF, AJW, GKL, and MMD conceptualized the study. MPL, AJW, JCR and GKL determined the methodology. MMD, GKL, JCR, PCK, AJW, JS, APP, AJC, and MPL collected field data. MMD, GKL, PCK, and AJW assisted with geochemistry. MPL supervised the work. MMD conducted data analysis and wrote the original draft, and all authors contributed to the review and editing of the paper. \n\nData availability. All datasets are included in the paper and Supplement. \n\nThe supplement related to this article is available online at: https://doi.org/10.5194/esurf-10-421-2022-supplement. \n\nCompeting interests. One author is a member of the editorial board of Earth Surface Dynamics. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare. \n\nReview statement. This paper was edited by Robert Hilton and reviewed by Jordon Hemingway and one anonymous referee.\n\n

Published - esurf-10-421-2022.pdf

Supplemental Material - esurf-10-421-2022-supplement.zip

", "abstract": "Arctic river systems erode permafrost in their banks and mobilize particulate organic carbon (OC). Meandering rivers can entrain particulate OC from permafrost many meters below the depth of annual thaw, potentially enabling the production of greenhouse gases. However, the amount and fate of permafrost OC that is mobilized by river erosion is uncertain. To constrain OC fluxes due to riverbank erosion and deposition, we collected riverbank and floodplain sediment samples along the Koyukuk River, which meanders through discontinuous permafrost in the Yukon River watershed, Alaska, USA, with an average migration rate of 0.52\u2009m\u2009yr\u207b\u00b9. We measured sediment total OC (TOC) content, radiocarbon activity, water content, bulk density, grain size, and floodplain stratigraphy. Radiocarbon activity and TOC content were higher in samples dominated by silt as compared to sand, which we used to map OC content onto floodplain stratigraphy and estimate carbon fluxes due to river meandering. Results showed that the Koyukuk River erodes and re-deposits a substantial flux of OC each year due to its depth and high migration rate, generating a combined OC flux of a similar magnitude to the floodplain net ecological productivity. However, sediment being eroded from cutbanks and deposited as point bars had similar OC stocks (mean\u2009\u00b1\u20091\u2009SD of 125.3\u00b113.1\u2009kg\u2009OC\u2009m\u207b\u00b2 in cutbanks versus 114.0\u00b115.7\u2009kg\u2009OC\u2009m\u207b\u00b2 in point bars) whether or not the banks contained permafrost. We also observed radiocarbon-depleted biospheric OC in both cutbanks and permafrost-free point bars. These results indicate that a substantial fraction of aged biospheric OC that is liberated from floodplains by bank erosion is subsequently re-deposited in point bars rather than being oxidized. The process of aging, erosion, and re-deposition of floodplain organic material may be intrinsic to river\u2013floodplain dynamics, regardless of permafrost content.", "date": "2022-05-10", "date_type": "published", "publication": "Earth Surface Dynamics", "volume": "10", "number": "3", "publisher": "European Geosciences Union", "pagerange": "421-435", "id_number": "CaltechAUTHORS:20220520-231800000", "issn": "2196-632X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220520-231800000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)" }, { "agency": "Terrestrial Hazards Observation and Reporting Center" }, { "agency": "Foster and Coco Stanback" }, { "agency": "Linde Family" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Center for Environmental Microbial Interactions (CEMI)" }, { "agency": "NSF", "grant_number": "ICER-2127442" }, { "agency": "NSF", "grant_number": "EAR-2031532" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Fannie and John Hertz Foundation" } ] }, "local_group": { "items": [ { "id": "Caltech-Center-for-Environmental-Microbial-Interactions-(CEMI)" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/esurf-10-421-2022", "primary_object": { "basename": "esurf-10-421-2022.pdf", "url": "https://authors.library.caltech.edu/records/s6z1q-7pv61/files/esurf-10-421-2022.pdf" }, "related_objects": [ { "basename": "esurf-10-421-2022-supplement.zip", "url": "https://authors.library.caltech.edu/records/s6z1q-7pv61/files/esurf-10-421-2022-supplement.zip" } ], "pub_year": "2022", "author_list": "Douglas, Madison M.; Li, Gen K.; et al." }, { "id": "https://authors.library.caltech.edu/records/v61xv-qqr84", "eprint_id": 114382, "eprint_status": "archive", "datestamp": "2023-08-22 15:29:43", "lastmod": "2025-11-21 02:26:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Derosa-Joseph", "name": { "family": "Derosa", "given": "Joseph" }, "orcid": "0000-0001-8672-4875" }, { "id": "Garrido-Barros-Pablo", "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Electrocatalytic Ketyl-Olefin Cyclization at a Favorable Applied Bias Enabled by a Concerted Proton\u2013Electron Transfer Mediator", "ispublished": "pub", "full_text_status": "public", "keywords": "Ketones, Electrodes, Hydrocarbons, Redox reactions, Cyclization; Inorganic Chemistry; Physical and Theoretical Chemistry", "note": "\u00a9 2022 American Chemical Society. \n\nReceived: March 14, 2022; Published: April 18, 2022. \n\nThe authors are grateful to the Department of Energy Basic Energy Sciences for support via Grant DE-SC0019136 and the donors of the American Chemical Society Petroleum Research Fund for support. J.D. thanks the Arnold and Mabel Beckman Foundation for a postdoctoral fellowship, and P.G.-B. thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship. J.C.P. acknowledges the Resnick Sustainability Institute for support of laboratory facilities. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ic2c00839_si_001.pdf

", "abstract": "Recent studies showcase reductive concerted proton\u2013electron transfer (CPET) as a powerful strategy for transferring a net hydrogen atom to organic substrates; however, direct application of CPET in the context of C\u2013C bond formation beyond homocoupling is underexplored. We report herein the expansion of electrocatalytic CPET (eCPET) using a Br\u00f8nsted base-appended cobaltocene mediator ([CpCoCp^(NMe\u2082)][OTf]) with keto-olefin substrates that undergo cyclization subsequent to ketyl radical generation via eCPET. Using acetophenone-derived substrates with tethered acrylates as radical acceptors, in the presence of tosylic acid, we demonstrate that ketyl-olefin cyclization is achieved by characterization of cis-lactone and alkene products. Mechanistic analysis of this 2 H\u207a/2 e\u207b process reveals a mixed order in substrate and acid and a Hammett plot with a modest negative slope, highlighting the contribution of sequential CPET and ET/PT steps involved in the overall rate of the reaction and providing support for initial O\u2013H bond formation. The ability to access ketyl radicals at comparatively mild reduction potentials via controlled potential electrolysis enables functional group tolerance across a range of substrates.", "date": "2022-05-02", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "61", "number": "17", "publisher": "American Chemical Society", "pagerange": "6672-6678", "id_number": "CaltechAUTHORS:20220419-936112000", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220419-936112000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019136" }, { "agency": "American Chemical Society Petroleum Research Fund" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Ram\u00f3n Areces Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.2c00839", "primary_object": { "basename": "ic2c00839_si_001.pdf", "url": "https://authors.library.caltech.edu/records/v61xv-qqr84/files/ic2c00839_si_001.pdf" }, "pub_year": "2022", "author_list": "Derosa, Joseph; Garrido-Barros, Pablo; et al." }, { "id": "https://authors.library.caltech.edu/records/57b8v-e0y47", "eprint_id": 110073, "eprint_status": "archive", "datestamp": "2023-08-22 15:28:32", "lastmod": "2025-11-20 23:23:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ghosh-Swarnava", "name": { "family": "Ghosh", "given": "Swarnava" }, "orcid": "0000-0003-3800-5264" }, { "id": "Bhattacharya-K", "name": { "family": "Bhattacharya", "given": "Kaushik" }, "orcid": "0000-0003-2908-5469" } ] }, "title": "Spectral quadrature for the first principles study of crystal defects: Application to magnesium", "ispublished": "pub", "full_text_status": "public", "keywords": "Spectral quadrature; Linear-Scaling; Density Functional Theory; Defects; Magnesium", "note": "\u00a9 2022 Elsevier. \n\nReceived 26 November 2020, Revised 16 November 2021, Accepted 29 January 2022, Available online 7 February 2022. \n\nThis research was performed when S.G. held a position at the California Institute of Technology. We thank the anonymous reviewers for their valuable comments and suggestions. The work was sponsored by the Army Research Laboratory and was accomplished under Cooperative Agreement Number W911NF-12-2-0022. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing the official policies, either expressed or implied, of the Army Research Laboratory or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein. The computations presented here were conducted on the Resnick High-Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology, and the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562. Part of this research used resources of the Oak Ridge Leadership Computing Facility, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory under contract DE-AC05-00OR22725. \n\nCRediT authorship contribution statement: Swarnava Ghosh: Conceptualization, Methodology, Software, Writing \u2013 review & editing. Kaushik Bhattacharya: Conceptualization, Methodology, Software, Writing \u2013 review & editing. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\n

Submitted - 2011.13517.pdf

", "abstract": "We present an accurate and efficient finite-difference formulation and parallel implementation of Kohn-Sham Density (Operator) Functional Theory (DFT) for non periodic systems embedded in a bulk environment. Specifically, employing non-local pseudopotentials, local reformulation of electrostatics, and truncation of the spatial Kohn-Sham Hamiltonian, and the Linear Scaling Spectral Quadrature method to solve for the pointwise electronic fields in real-space and the non-local component of the atomic force, we develop a parallel finite difference framework suitable for distributed memory computing architectures to simulate non-periodic systems embedded in a bulk environment. Choosing examples from magnesium-aluminum alloys, we first demonstrate the convergence of energies and forces with respect to spectral quadrature polynomial order, and the width of the spatially truncated Hamiltonian. Next, we demonstrate the parallel scaling of our framework, and show that the computation time and memory scale linearly with respect to the number of atoms. Next, we use the developed framework to simulate isolated point defects and their interactions in magnesium-aluminum alloys. Our findings conclude that the binding energies of divacancies, Al solute-vacancy and two Al solute atoms are anisotropic and are dependent on cell size. Furthermore, the binding is favorable in all three cases.", "date": "2022-05-01", "date_type": "published", "publication": "Journal of Computational Physics", "volume": "456", "publisher": "Elsevier", "pagerange": "Art. No. 111035", "id_number": "CaltechAUTHORS:20210729-195436164", "issn": "0021-9991", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210729-195436164", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Laboratory", "grant_number": "W911NF-12-2-0022" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.jcp.2022.111035", "primary_object": { "basename": "2011.13517.pdf", "url": "https://authors.library.caltech.edu/records/57b8v-e0y47/files/2011.13517.pdf" }, "pub_year": "2022", "author_list": "Ghosh, Swarnava and Bhattacharya, Kaushik" }, { "id": "https://authors.library.caltech.edu/records/w2ev0-snj25", "eprint_id": 115123, "eprint_status": "archive", "datestamp": "2023-10-09 21:03:28", "lastmod": "2025-11-21 04:05:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nghiem-Justin-A", "name": { "family": "Nghiem", "given": "Justin A." }, "orcid": "0000-0003-2772-9945" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Li-Gen-K", "name": { "family": "Li", "given": "Gen K." }, "orcid": "0000-0002-6300-3570" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "A Mechanistic Model for Mud Flocculation in Freshwater Rivers", "ispublished": "pub", "full_text_status": "public", "keywords": "mud; flocculation; suspended sediment; cohesive sediment; organic carbon; Earth-Surface Processes; Geophysics", "note": "\u00a9 2022. American Geophysical Union. \n\nIssue Online: 17 May 2022; Version of Record online: 17 May 2022; Accepted manuscript online: 06 May 2022; Manuscript accepted: 02 April 2022; Manuscript revised: 11 March 2022; Manuscript received: 15 August 2021. \n\nJN acknowledges NASA FINESST Grant 80NSSC20K1645. WWF and MPL acknowledge funding by the Discovery Fund and the Resnick Sustainability Institute at Caltech. GKL acknowledges the Caltech Geology Option Postdoc Fellowship. MPL acknowledges funding from the NASA Delta-X project by the Science Mission Directorate's Earth Science Division through the Earth Venture Suborbital-3 Program NNH17ZDA001N-EVS3 and the National Science Foundation Geomorphology and Land-use Dynamics Grant No. 2136991. The authors thank reviewer Scott Wright and four anonymous reviewers for their feedback, which improved the paper. The authors also thank Editor Ton Hoitink and Associate Editor Florent Grasso. \n\nData Availability Statement: The suspended sediment concentration-depth profile, grain size distribution, and geochemical data used in this paper are freely available in the respective original publications. The authors are grateful to J. Bouchez, E. Dingle, and J. Shelley for sharing data used in this paper. Derived data are available online at https://doi.org/10.22002/D1.8962.\n\n

Published - 2021JF006392.pdf

Accepted Version - 2021JF006392-acc.pdf

Supplemental Material - 2021jf006392-sup-0001-supporting_information_si-s01.docx

", "abstract": "The transport and deposition of mud in rivers are key processes in fluvial geomorphology and biogeochemical cycles. Recent work indicates that flocculation might regulate fluvial mud transport by increasing mud settling velocities, but we lack a calibrated mechanistic model for flocculation in freshwater rivers. Here, we developed and calibrated a semi-empirical model for floc diameter and settling velocity in rivers. We compiled a global data set of river suspended sediment concentration-depth profiles and inverted them for in situ settling velocity using the Rouse-Vanoni equation. On average, clay and silt (diameters <39 \u03bcm) are flocculated with settling velocity of 1.8 mm s\u207b\u00b9 and floc diameter of 130 \u03bcm. Among model variables, Kolmogorov microscale has the strongest positive correlation with floc diameter, supporting the idea that turbulent shear limits floc size. Sediment Al/Si (a mineralogy proxy) has the strongest negative correlation with floc diameter and settling velocity, indicating the importance of clay abundance and composition for flocculation. Floc settling velocity increases with greater mud and organic matter concentrations, consistent with flocculation driven by particle collisions and binding by organic matter which is often concentrated in mud. Relative charge density (a salinity proxy) correlates with smaller floc settling velocities, a finding that might reflect the primary particle size distribution and physical hosting of organic matter. The calibrated model explains river floc settling velocity data within a factor of about two. Results highlight that flocculation can impact the fate of mud and particulate organic carbon, holding implications for global biogeochemical cycles.", "date": "2022-05", "date_type": "published", "publication": "Journal of Geophysical Research. Earth Surface", "volume": "127", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021JF006392", "id_number": "CaltechAUTHORS:20220610-583154400", "issn": "2169-9003", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220610-583154400", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC20K1645" }, { "agency": "Caltech Discovery Fund" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Division of Geological and Planetary Sciences" }, { "agency": "NASA", "grant_number": "NNH17ZDA001N-EVS3" }, { "agency": "NSF", "grant_number": "EAR-2136991" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021jf006392", "primary_object": { "basename": "2021JF006392-acc.pdf", "url": "https://authors.library.caltech.edu/records/w2ev0-snj25/files/2021JF006392-acc.pdf" }, "related_objects": [ { "basename": "2021JF006392.pdf", "url": "https://authors.library.caltech.edu/records/w2ev0-snj25/files/2021JF006392.pdf" }, { "basename": "2021jf006392-sup-0001-supporting_information_si-s01.docx", "url": "https://authors.library.caltech.edu/records/w2ev0-snj25/files/2021jf006392-sup-0001-supporting_information_si-s01.docx" } ], "pub_year": "2022", "author_list": "Nghiem, Justin A.; Fischer, Woodward W.; et al." }, { "id": "https://authors.library.caltech.edu/records/egxk9-42588", "eprint_id": 114547, "eprint_status": "archive", "datestamp": "2023-08-22 15:23:21", "lastmod": "2025-11-21 00:33:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narita-Kai", "name": { "family": "Narita", "given": "Kai" }, "orcid": "0000-0002-3867-8234" }, { "id": "Saccone-Max-A", "name": { "family": "Saccone", "given": "Max A." }, "orcid": "0000-0003-3846-2908" }, { "id": "Sun-Yuchun", "name": { "family": "Sun", "given": "Yuchun" }, "orcid": "0000-0002-7028-3523" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Additive manufacturing of 3D batteries: a perspective", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Additive manufacturing; 3D printing; Batteries; 3D batteries; Stereolithography; Vat photopolymerization; Interdigitated; Direct ink writing; Fused deposition modeling; Selective laser sintering; SLA; VP; DIW; FDM; SLS", "note": "\u00a9 The Author(s), under exclusive licence to The Materials Research Society 2022. \n\nReceived 24 January 2022; Accepted 11 April 2022; Published 28 April 2022. \n\nThe authors gratefully acknowledge financial support from the Resnick Sustainability Institute at Caltech, the Keck Institute for Space Studies at Caltech, and the DoD through J.R.G.'s Vannevar Bush Faculty Fellowship. K.N. acknowledges a graduate fellowship from the Masason Foundation. M.A.S. acknowledges a graduate fellowship from the Resnick Sustainability Institute at Caltech. \n\nData and code availability: The data and code generated and/or analyzed in this study are available from the corresponding author on reasonable request. \n\nConflict of interest: K.N. is an employee of 24M Technologies, Inc., a company that manufactures Li-ion batteries.", "abstract": "Additive manufacturing (AM) enables the fabrication of battery materials with complex geometries. When battery components can take arbitrary form factors, opportunities emerge for creating electrode configurations with improved power density, reduced weight, and excellent mechanical stability. We provide a perspective on recent progress in AM of 3D batteries, discussing relevant techniques, materials, designs, and applications. We highlight advantages and limitations associated with battery electrodes fabricated by direct ink writing, fused deposition modeling, vat photopolymerization, and selective laser sintering. Additionally, we discuss optimal geometries and compatible materials for anode, cathode, and electrolyte of fully 3D batteries. To increase transparency and utility in the field, we suggest a standardized set of reporting metrics for 3D batteries. Finally, we identify key opportunities for implementation where 3D batteries can provide critical advantages such as shape conformability and the ability to serve as multifunctional or structural components.", "date": "2022-05", "date_type": "published", "publication": "Journal of Materials Research", "volume": "37", "number": "9", "publisher": "Springer", "pagerange": "1535-1546", "id_number": "CaltechAUTHORS:20220502-202342151", "issn": "0884-2914", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220502-202342151", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "Vannever Bush Faculty Fellowship" }, { "agency": "Masason Foundation" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1557/s43578-022-00562-w", "pub_year": "2022", "author_list": "Narita, Kai; Saccone, Max A.; et al." }, { "id": "https://authors.library.caltech.edu/records/700y2-smp69", "eprint_id": 114168, "eprint_status": "archive", "datestamp": "2023-08-22 15:06:38", "lastmod": "2025-11-21 00:30:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cagan-David-A", "name": { "family": "Cagan", "given": "David A." }, "orcid": "0000-0002-4719-2789" }, { "id": "B\u00edm-Daniel", "name": { "family": "B\u00edm", "given": "Daniel" }, "orcid": "0000-0003-3100-4293" }, { "id": "Silva-Breno", "name": { "family": "Silva", "given": "Breno" } }, { "id": "Kazmierczak-Nathanael-P", "name": { "family": "Kazmierczak", "given": "Nathanael P." }, "orcid": "0000-0002-7822-6769" }, { "id": "McNicholas-Brendon-J", "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "Elucidating the Mechanism of Excited-State Bond Homolysis in Nickel\u2013Bipyridine Photoredox Catalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "Photodissociation, Kinetic parameters, Metal to ligand charge transfer, Ligands, Quantum mechanics; Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "\u00a9 2022 American Chemical Society. \n\nReceived: February 3, 2022; Published: March 30, 2022. \n\nD.A.C. is a National Science Foundation Graduate Research Fellow (DGE-1745301) and is supported by a National Academies of Science, Engineering, and Medicine Ford Foundation Predoctoral Fellowship. B.S. acknowledges funding through a Southern California Edison WAVE fellowship at Caltech. N.P.K. acknowledges support from the Hertz Fellowship and from the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1745301. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No. 883987 (D.B.). Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R35-GM142595). The authors also acknowledge M. K. Takase in the Beckman Institute X-ray crystallography facility. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1870778.pdf

Supplemental Material - ja2c01356_si_001.pdf

", "abstract": "Ni 2,2\u2032\u2013bipyridine (bpy) complexes are commonly employed photoredox catalysts of bond-forming reactions in organic chemistry. However, the mechanisms by which they operate are still under investigation. One potential mode of catalysis is via entry into Ni(I)/Ni(III) cycles, which can be made possible by light-induced, excited-state Ni(II)\u2013C bond homolysis. Here, we report experimental and computational analyses of a library of Ni(II)\u2013bpy aryl halide complexes, Ni(^Rbpy)(^(R\u2032)Ph)Cl (R = MeO, t-Bu, H, MeOOC; R\u2032 = CH\u2083, H, OMe, F, CF\u2083), to illuminate the mechanism of excited-state bond homolysis. At given excitation wavelengths, photochemical homolysis rate constants span 2 orders of magnitude across these structures and correlate linearly with Hammett parameters of both bpy and aryl ligands, reflecting structural control over key metal-to-ligand charge-transfer (MLCT) and ligand-to-metal charge-transfer (LMCT) excited-state potential energy surfaces (PESs). Temperature- and wavelength-dependent investigations reveal moderate excited-state barriers (\u0394H^\u2021 \u223c 4 kcal mol\u207b\u00b9) and a minimum energy excitation threshold (\u223c55 kcal mol\u207b\u00b9, 525 nm), respectively. Correlations to electronic structure calculations further support a mechanism in which repulsive triplet excited-state PESs featuring a critical aryl-to-Ni LMCT lead to bond rupture. Structural control over excited-state PESs provides a rational approach to utilize photonic energy and leverage excited-state bond homolysis processes in synthetic chemistry.", "date": "2022-04-13", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "144", "number": "14", "publisher": "American Chemical Society", "pagerange": "6516-6531", "id_number": "CaltechAUTHORS:20220406-18315469", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220406-18315469", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Ford Foundation" }, { "agency": "Southern California Edison" }, { "agency": "Fannie and John Hertz Foundation" }, { "agency": "Marie Curie Fellowship", "grant_number": "883987" }, { "agency": "NIH", "grant_number": "R35GM142595" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.2c01356", "pmcid": "PMC9979631", "primary_object": { "basename": "nihms-1870778.pdf", "url": "https://authors.library.caltech.edu/records/700y2-smp69/files/nihms-1870778.pdf" }, "related_objects": [ { "basename": "ja2c01356_si_001.pdf", "url": "https://authors.library.caltech.edu/records/700y2-smp69/files/ja2c01356_si_001.pdf" } ], "pub_year": "2022", "author_list": "Cagan, David A.; B\u00edm, Daniel; et al." }, { "id": "https://authors.library.caltech.edu/records/jy1b9-mvm78", "eprint_id": 113566, "eprint_status": "archive", "datestamp": "2023-10-09 20:57:17", "lastmod": "2025-11-20 23:41:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Begu\u0161i\u0107-Tomislav", "name": { "family": "Begu\u0161i\u0107", "given": "Tomislav" }, "orcid": "0000-0002-7942-4134" }, { "id": "Tao-Xuecheng", "name": { "family": "Tao", "given": "Xuecheng" }, "orcid": "0000-0003-2907-3839" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Equilibrium\u2013nonequilibrium ring-polymer molecular dynamics for nonlinear spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2022 Author(s). Published under an exclusive license by AIP Publishing. \n\nSubmitted: 2 February 2022; Accepted: 15 March 2022; Published Online: 7 April 2022. \n\nThe authors thank Kenneth A. Jung, Roman Korol, and Jorge L. Rosa-Ra\u00edces for helpful discussions. T.B. acknowledges financial support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship (Grant No. P2ELP2-199757). G.A.B. and T.F.M. gratefully acknowledge support from the National Science Foundation Chemical Structure, Dynamics and Mechanisms program (Grant No. CHE-1665467). The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. \n\nData Availability: The data that support the findings of this study are available from the corresponding author upon reasonable request. \n\nThe authors have no conflicts to disclose.\n\n

Published - 131102_1_online.pdf

Accepted Version - 2111-02436.pdf

Supplemental Material - sm.pdf

", "abstract": "Two-dimensional Raman and hybrid terahertz-Raman spectroscopic techniques provide invaluable insight into molecular structures and dynamics of condensed-phase systems. However, corroborating experimental results with theory is difficult due to the high computational cost of incorporating quantum-mechanical effects in the simulations. Here, we present the equilibrium\u2013nonequilibrium ring-polymer molecular dynamics (RPMD), a practical computational method that can account for nuclear quantum effects on the two-time response function of nonlinear optical spectroscopy. Unlike a recently developed approach based on the double Kubo transformed (DKT) correlation function, our method is exact in the classical limit, where it reduces to the established equilibrium-nonequilibrium classical molecular dynamics method. Using benchmark model calculations, we demonstrate the advantages of the equilibrium\u2013nonequilibrium RPMD over classical and DKT-based approaches. Importantly, its derivation, which is based on the nonequilibrium RPMD, obviates the need for identifying an appropriate Kubo transformed correlation function and paves the way for applying real-time path-integral techniques to multidimensional spectroscopy.", "date": "2022-04-07", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "156", "number": "13", "publisher": "American Institute of Physics", "pagerange": "Art. No. 131102", "id_number": "CaltechAUTHORS:20220223-214612882", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220223-214612882", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2ELP2-199757" }, { "agency": "NSF", "grant_number": "CHE-1665467" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1063/5.0087156", "primary_object": { "basename": "131102_1_online.pdf", "url": "https://authors.library.caltech.edu/records/jy1b9-mvm78/files/131102_1_online.pdf" }, "related_objects": [ { "basename": "2111-02436.pdf", "url": "https://authors.library.caltech.edu/records/jy1b9-mvm78/files/2111-02436.pdf" }, { "basename": "sm.pdf", "url": "https://authors.library.caltech.edu/records/jy1b9-mvm78/files/sm.pdf" } ], "pub_year": "2022", "author_list": "Begu\u0161i\u0107, Tomislav; Tao, Xuecheng; et al." }, { "id": "https://authors.library.caltech.edu/records/3yw1a-mtp69", "eprint_id": 114177, "eprint_status": "archive", "datestamp": "2023-08-22 15:12:47", "lastmod": "2025-11-20 23:31:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hamann-Kathryn-R", "name": { "family": "Hamann", "given": "Kathryn R." }, "orcid": "0000-0003-1163-7173" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" } ] }, "title": "Plastic Morphological Response to Spectral Shifts during Inorganic Phototropic Growth", "ispublished": "pub", "full_text_status": "public", "keywords": "photoelectrodeposition photoelectrochemistry; mesostructure; template-free; maskless; optical", "note": "\u00a9 2022 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).\n\nReceived 31 December 2021. Accepted 4 March 2022. Revised 3 March 2022. Published online 4 April 2022. \n\nThis work was supported by the National Science Foundation, Directorate for Mathematical & Physical Sciences, Division of Materials Research under Award No. DMR-1905963. The authors gratefully acknowledge J.R. Thompson for insightful discussions, E.D. Simonoff and S. Yalamanchili for assistance with substrate preparation, and R. Gerhart, N. Hart, and B. Markowicz for assistance with photoelectrochemical cell fabrication. KRH and MCM acknowledge Graduate Research Fellowships from the National Science Foundation. MCM also acknowledges the Resnick Institute at Caltech for fellowship support. \n\nThe authors declare no competing financial interest.\n\n

Published - au1c00588.pdf

Supplemental Material - au1c00588_si_001.pdf

", "abstract": "Plants exhibit phototropism in which growth is directed toward sunlight and demonstrate morphological plasticity in response to changes in the spectral distribution of the incident illumination. Inorganic phototropic growth via template-free, light-directed electrochemical deposition of semiconductor material can spontaneously generate highly ordered mesostructures with anisotropic, nanoscale lamellar features that exhibit a pitch proportional to the wavelength (\u03bb) of the stimulating illumination. In this work, Se\u2013Te films were generated via a two-step inorganic phototropic growth process using a series of narrowband light-emitting diode sources with discrete output wavelengths (\u03bb\u2080 \u2260 \u03bb\u2081). Analogous to the plasticity observed in plants, changes in illumination wavelength from \u03bb\u2080 to \u03bb\u2081 resulted in morphological changes including feature branching, termination, and/or fusion along the growth direction. The interfacial feature pitch changed with the growth duration, in some cases in a notably nonmonotonic fashion, and eventually matched that obtained for growth using only \u03bb\u2081. Simulated morphologies generated by modeling light\u2013material interactions at the growth interface closely matched the evolved structures observed experimentally, indicating that the characteristics of the optical stimulation produce the observed plastic response during inorganic phototropic growth. Examination of the interfacial electric field modulation for \u03bb1 illumination of simplified structures, representative of those generated experimentally, revealed the interfacial light scattering and concentration behavior that directed phototropic growth away from equilibrium, as well as the emergent nature of the phenomena that reestablish equilibrium.", "date": "2022-04-06", "date_type": "published", "publication": "JACS Au", "volume": "2", "number": "4", "publisher": "American Chemical Society", "pagerange": "865-874", "id_number": "CaltechAUTHORS:20220406-400053753", "issn": "2691-3704", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220406-400053753", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1905963" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacsau.1c00588", "pmcid": "PMC9088297", "primary_object": { "basename": "au1c00588.pdf", "url": "https://authors.library.caltech.edu/records/3yw1a-mtp69/files/au1c00588.pdf" }, "related_objects": [ { "basename": "au1c00588_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3yw1a-mtp69/files/au1c00588_si_001.pdf" } ], "pub_year": "2022", "author_list": "Hamann, Kathryn R.; Meier, Madeline C.; et al." }, { "id": "https://authors.library.caltech.edu/records/8jxr7-e6124", "eprint_id": 98723, "eprint_status": "archive", "datestamp": "2023-08-22 15:02:20", "lastmod": "2025-11-21 18:48:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roumeli-Eleftheria", "name": { "family": "Roumeli", "given": "Eleftheria" }, "orcid": "0000-0002-2828-1428" }, { "id": "Hendrickx-Rodinde", "name": { "family": "Hendrickx", "given": "Rodinde" } }, { "id": "Bonanomi-Luca", "name": { "family": "Bonanomi", "given": "Luca" } }, { "id": "Vashisth-Aniruddh", "name": { "family": "Vashisth", "given": "Aniruddh" }, "orcid": "0000-0002-4740-1296" }, { "id": "Rinaldi-Katherine-Z", "name": { "family": "Rinaldi", "given": "Katherine" }, "orcid": "0000-0002-0746-2852" }, { "id": "Daraio-C", "name": { "family": "Daraio", "given": "Chiara" }, "orcid": "0000-0001-5296-4440" } ] }, "title": "Biological matrix composites from cultured plant cells", "ispublished": "pub", "full_text_status": "public", "keywords": "sustainable materials; biocomposites; biopolymers", "note": "\u00a9 2022 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). \n\nEdited by Joanna Aizenberg, Harvard University, Cambridge, MA; received November 6, 2021; accepted February 3, 2022.\nPublished April 4, 2022. \n\nWe thank Mr. M. Ladinsky, Dr. S. Amanatidis, Dr. A. M. Jimenez, Dr. Y.Wei,Dr. M. Mello,Mr. A. Carim, Ms. S. Antilla, and Mr.D. A.Nguyen for support in experiments.We thank Dr. R. Di Giacomo for useful discussions and Prof. N. Lewis for providing access to the Raman facilities.We thank Caltech Kavli Nanoscience Institute, Gordon and Betty Moore, and the Beckman Foundation for support of electron microscopy facilities and the Caltech Beckman Institute and the Arnold and Mabel Beckman Foundation for supporting the laser scanning imaging facilities. This work was supported in part by the Resnick Sustainability Institute at Caltech. \n\nAuthor contributions: E.R., L.B., and C.D. designed research; E.R., R.H., L.B., A.V., and K.R. performed research; E.R. and A.V. analyzed data; and E.R. and C.D. wrote the paper. \n\nThe authors declare no competing interest. \n\nData Availability: All study data are included in the article and/or SI Appendix. \n\nThis article contains supporting information online at\nhttps://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2119523119/-/DCSupplemental.\n\n

Published - pnas.2119523119.pdf

Submitted - 1909.01926.pdf

Supplemental Material - pnas.2119523119.sapp.pdf

", "abstract": "We present an approach to fabricate biological matrix composites made entirely from cultured plant cells. We utilize the cell's innate ability to synthesize nanofibrillar cell walls, which serve as the composite's fundamental building blocks. Following a controlled compression/dehydration process, the cells arrange into lamellar structures with hierarchical features. We demonstrate that the native cell wall nanofibrils tether adjacent cells together through fibrillar interlocking and intermolecular hydrogen bonding. These interactions facilitate intercellular adhesion and eliminate the need for other binders. Our fabrication process utilizes the entire plant cell, grown in an in vitro culture; requires no harsh chemical treatments or waste-generating extraction or selection processes; and leads to bulk biocomposites that can be produced in situ and biodegrade in soil. The final mechanical properties are comparable to commodity plastics and can be further modulated by introducing filler particles.", "date": "2022-04-04", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "119", "number": "15", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2119523119", "id_number": "CaltechAUTHORS:20190918-130321479", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190918-130321479", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Kavli Nanoscience Institute" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2119523119", "pmcid": "PMC9169740", "primary_object": { "basename": "1909.01926.pdf", "url": "https://authors.library.caltech.edu/records/8jxr7-e6124/files/1909.01926.pdf" }, "related_objects": [ { "basename": "pnas.2119523119.pdf", "url": "https://authors.library.caltech.edu/records/8jxr7-e6124/files/pnas.2119523119.pdf" }, { "basename": "pnas.2119523119.sapp.pdf", "url": "https://authors.library.caltech.edu/records/8jxr7-e6124/files/pnas.2119523119.sapp.pdf" } ], "pub_year": "2022", "author_list": "Roumeli, Eleftheria; Hendrickx, Rodinde; et al." }, { "id": "https://authors.library.caltech.edu/records/benpx-wj703", "eprint_id": 113672, "eprint_status": "archive", "datestamp": "2023-08-22 14:35:11", "lastmod": "2025-11-21 02:24:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Watkins-Nicholas-B", "name": { "family": "Watkins", "given": "Nicholas B." }, "orcid": "0000-0001-7251-9387" }, { "id": "Muzzillo-Christopher", "name": { "family": "Muzzillo", "given": "Christopher" }, "orcid": "0000-0002-6492-0098" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias" }, "orcid": "0000-0003-0091-2045" }, { "id": "Kan-Kevin-S", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Zakutayev-Andriy", "name": { "family": "Zakutayev", "given": "Andriy" }, "orcid": "0000-0002-3054-5525" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Molecular Coatings Improve the Selectivity and Durability of CO\u2082 Reduction Chalcogenide Photocathodes", "ispublished": "pub", "full_text_status": "public", "keywords": "Coating materials, Additives, Photonics, Cadmium sulfide, Electrodes; Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "\u00a9 2022 American Chemical Society. \n\nReceived 18 December 2021. Accepted 23 February 2022. Published online 1 March 2022. \n\nThis material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. National Renewable Energy Laboratory is operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. The Resnick Sustainability Institute at Caltech is also acknowledged for its support of enabling infrastructure and facilities. \n\nThe views expressed in this article do not necessarily represent the views of the DOE or the U.S. Government. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nz1c02762_si_001.pdf

", "abstract": "The quest for solar-driven conversion of carbon dioxide to chemicals and fuels hinges upon the identification of an efficient, durable, and selective photocathode. Chalcogenide p-type semiconductors exemplified by chalcopyrite Cu(In,Ga)Se\u2082 (CIGS) have been effectively deployed as photocathodes. However, selectivity toward CO\u2082 reduction and durability of the commonly used CdS adlayer remain primary challenges. Here, we demonstrate that for the wide band gap CuGa\u2083Se\u2085 chalcopyrite absorber these challenges are well addressed by an organic coating generated in situ from an N,N\u2032-(1,4-phenylene)bispyridinium ditriflate salt in the electrolyte. The molecular additive provides a 30-fold increase in selectivity toward CO\u2082R products compared to the unmodified system and lowers Cd corrosion at least 10-fold. This dual functionality highlights the promise of hybrid solid-state-molecular photocathodes for enabling durable and efficient solar fuel systems.", "date": "2022-03-11", "date_type": "published", "publication": "ACS Energy Letters", "volume": "7", "number": "3", "publisher": "American Chemical Society", "pagerange": "1195-1201", "id_number": "CaltechAUTHORS:20220301-900116000", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220301-900116000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1021/acsenergylett.1c02762", "primary_object": { "basename": "nz1c02762_si_001.pdf", "url": "https://authors.library.caltech.edu/records/benpx-wj703/files/nz1c02762_si_001.pdf" }, "pub_year": "2022", "author_list": "Lai, Yungchieh; Watkins, Nicholas B.; et al." }, { "id": "https://authors.library.caltech.edu/records/ppn6p-w4f28", "eprint_id": 112157, "eprint_status": "archive", "datestamp": "2023-08-20 07:15:24", "lastmod": "2025-11-21 03:20:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mazza-Michael-F", "name": { "family": "Mazza", "given": "Michael F." }, "orcid": "0000-0003-3995-3100" }, { "id": "Cab\u00e1n-Acevedo-Miguel", "name": { "family": "Cab\u00e1n-Acevedo", "given": "Miguel" }, "orcid": "0000-0003-0054-8044" }, { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Thompson-Annelise-C", "name": { "family": "Thompson", "given": "Annelise C." }, "orcid": "0000-0003-2414-7050" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Selective-Area, Water-Free Atomic Layer Deposition of Metal Oxides on Graphene Defects", "ispublished": "pub", "full_text_status": "public", "keywords": "atomic layer deposition, graphene, defect driven reactivity, defect passivation, device integration", "note": "\u00a9 2021 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0). \n\nReceived 20 September 2021. Accepted 11 November 2021. Revised 9 November 2021. Published online 19 November 2021. \n\nM.F.M. and N.S.L. acknowledge support from the U.S. Department of Energy under Award DE-FG02-04ER15483. M.C. acknowledges support from the Ford Foundation under the Postdoctoral Scholar Fellowship program. M.C. acknowledges support from the National Science Foundation CCI Solar Fuels Program under Grant No. CHE-1305124. A.C.T. and M.C.M. acknowledge support from National Science Foundation graduate research fellowships. M.C.M. also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. Research was in part carried out at the Molecular Materials Research Center in the Beckman Institute at the California Institute of Technology. \n\nThe authors declare no competing financial interest.\n\n

Published - acsmaterialsau.1c00049.pdf

Supplemental Material - mg1c00049_si_001.pdf

", "abstract": "Passivating defective regions on monolayer graphene with metal oxides remains an active area of research for graphene device integration. To effectively passivate these regions, a water-free atomic layer deposition (ALD) recipe was developed and yielded selective-area ALD (sa-ALD) of mixed-metal oxides onto line defects in monolayer graphene. The anisotropically deposited film targeted high-energy defect sites that were formed during synthesis or transfer of the graphene layer. The passivating layer exceeded 10 nm thickness with minimal deposition onto the basal plane of graphene. The mixed-metal oxide film was of comparable quality to films deposited using nonselective water-based ALD methods, as shown by X-ray photoelectron spectroscopy. The development of sa-ALD techniques to target defect regions on the graphene sheet, while keeping the basal plane intact, will provide a new mechanism to passivate graphene defects and modify the electronic and physical properties of graphene.", "date": "2022-03-09", "date_type": "published", "publication": "ACS Materials Au", "volume": "2", "number": "2", "publisher": "American Chemical Society", "pagerange": "74-78", "id_number": "CaltechAUTHORS:20211201-231211106", "issn": "2694-2461", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211201-231211106", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-04ER15483" }, { "agency": "Ford Foundation" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" } ] }, "doi": "10.1021/acsmaterialsau.1c00049", "pmcid": "PMC9888651", "primary_object": { "basename": "acsmaterialsau.1c00049.pdf", "url": "https://authors.library.caltech.edu/records/ppn6p-w4f28/files/acsmaterialsau.1c00049.pdf" }, "related_objects": [ { "basename": "mg1c00049_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ppn6p-w4f28/files/mg1c00049_si_001.pdf" } ], "pub_year": "2022", "author_list": "Mazza, Michael F.; Cab\u00e1n-Acevedo, Miguel; et al." }, { "id": "https://authors.library.caltech.edu/records/pdg32-gfd78", "eprint_id": 113477, "eprint_status": "archive", "datestamp": "2023-08-22 14:31:31", "lastmod": "2025-11-21 00:22:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Heejun", "name": { "family": "Lee", "given": "Heejun" }, "orcid": "0000-0002-0439-3863" }, { "id": "Ahn-Jun-Myun", "name": { "family": "Ahn", "given": "Jun Myun" } }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Citek-Cooper", "name": { "family": "Citek", "given": "Cooper" }, "orcid": "0000-0001-9376-8200" }, { "id": "Yin-Haolin", "name": { "family": "Yin", "given": "Haolin" }, "orcid": "0000-0002-2063-8605" }, { "id": "Fu-G-C", "name": { "family": "Fu", "given": "Gregory C." }, "orcid": "0000-0002-0927-680X" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Investigation of the C\u2013N Bond-Forming Step in a Photoinduced, Copper-Catalyzed Enantioconvergent N\u2013Alkylation: Characterization and Application of a Stabilized Organic Radical as a Mechanistic Probe", "ispublished": "pub", "full_text_status": "public", "keywords": "Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "\u00a9 2022 American Chemical Society. \n\nReceived 14 December 2021. Published online 15 February 2022. \n\nSupport has been provided by the National Institutes of Health (National Institute of General Medical Sciences: R01-109194). We are grateful to the Dow Innovation Fund for support of our EPR facility and to the Beckman Institute X-ray Crystallography Facility. The Resnick Sustainability Institute at Caltech is acknowledged for its support of enabling facilities. J.M.A. acknowledges the National Sciences and Engineering Research Council (NSERC) of Canada for a graduate research fellowship. J.C.P. and G.C.F. dedicate this contribution to the memory of our colleague, mentor, and friend Robert H. Grubbs. \n\nThe authors declare no competing financial interest. \n\nCCDC 2128476\u20132128480 contain the supplementary crystallographic data for this paper.\n\n

Accepted Version - nihms-1820516.pdf

Supplemental Material - ja1c13151_si_001.pdf

Supplemental Material - ja1c13151_si_002.txt

", "abstract": "Whereas photoinduced, copper-catalyzed couplings of nitrogen nucleophiles with alkyl electrophiles have recently been shown to provide an attractive approach to achieving a variety of enantioselective C\u2013N bond constructions, mechanistic studies of these transformations have lagged the advances in reaction development. Herein we provide mechanistic insight into a previously reported photoinduced, copper-catalyzed enantioconvergent C\u2013N coupling of a carbazole nucleophile with a racemic tertiary \u03b1-haloamide electrophile. Building on the isolation of a copper(II) model complex whose EPR parameters serve as a guide, we independently synthesize two key intermediates in the proposed catalytic cycle, a copper(II) metalloradical (L*Cu^(II)(carb\u2032)\u2082) (L* = a monodentate chiral phosphine ligand; carb\u2032 = a carbazolide ligand), as well as a tertiary \u03b1-amide organic radical (R\u00b7); the generation and characterization of R\u00b7 was guided by DFT calculations, which suggested that it would be stable to homocoupling. Continuous-wave (CW) and pulse EPR studies, along with corresponding DFT calculations, are among the techniques used to characterize these reactive radicals. We establish that these two radicals do indeed combine to furnish the C\u2013N coupling product in good yield and with significant enantiomeric excess (77% yield, 55% ee), thereby supporting the chemical competence of these proposed intermediates. DFT calculations are consistent with R\u00b7 initially binding to copper(II) via a dative interaction from the closed-shell carbonyl oxygen atom of the radical, which positions the \u03b1-carbon for direct reaction with the copper(II)-bound carbazole N atom, to generate the C\u2013N bond with enantioselectivity, without the formation of an alkylcopper(III) intermediate.", "date": "2022-03-09", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "144", "number": "9", "publisher": "American Chemical Society", "pagerange": "4114-4123", "id_number": "CaltechAUTHORS:20220216-527740512", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220216-527740512", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01109194" }, { "agency": "Dow Innovation Fund" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.1c13151", "pmcid": "PMC9269863", "primary_object": { "basename": "nihms-1820516.pdf", "url": "https://authors.library.caltech.edu/records/pdg32-gfd78/files/nihms-1820516.pdf" }, "related_objects": [ { "basename": "ja1c13151_si_002.txt", "url": "https://authors.library.caltech.edu/records/pdg32-gfd78/files/ja1c13151_si_002.txt" }, { "basename": "ja1c13151_si_001.pdf", "url": "https://authors.library.caltech.edu/records/pdg32-gfd78/files/ja1c13151_si_001.pdf" } ], "pub_year": "2022", "author_list": "Lee, Heejun; Ahn, Jun Myun; et al." }, { "id": "https://authors.library.caltech.edu/records/v9k41-6mf70", "eprint_id": 112067, "eprint_status": "archive", "datestamp": "2023-10-05 23:13:14", "lastmod": "2025-11-21 02:26:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Perry-Elena-K", "name": { "family": "Perry", "given": "Elena K." }, "orcid": "0000-0002-7151-1479" }, { "id": "Newman-D-K", "name": { "family": "Newman", "given": "Dianne K." }, "orcid": "0000-0003-1647-1918" } ] }, "title": "Prevalence and Correlates of Phenazine Resistance in Culturable Bacteria from a Dryland Wheat Field", "ispublished": "pub", "full_text_status": "public", "keywords": "correlates, dryland wheat, efflux pumps, phenazines, resistance, rhizosphere, toxicity", "note": "\u00a9 2022 American Society for Microbiology. \n\nReceived 23 November 2021; Accepted 1 February 2022; Accepted manuscript posted online 9 February 2022; Published 22 March 2022. \n\nWe thank Linda Thomashow and David Weller of the USDA Agricultural Research Service for providing the wheat rhizosphere and soil samples used in this study, and the members of the Newman lab for helpful feedback throughout the process of designing and analyzing the results of the PCA resistance screen. We also thank Zevin Condiotte for assistance with the initial rounds of testing the design of the PCA resistance screen and Richard Horak for assistance with extracting genomic DNA. \n\nThis material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant no. DGE\u20101745301. This work was also supported by grants to D.K.N. from the ARO (W911NF-17-1-0024), NIH (1R01AI127850-01A1), and the Resnick Sustainability Institute at Caltech. \n\nWe also thank the Doren Family Foundation for their support. \n\nWe declare no conflict of interest. \n\nData availability: The metagenomic sequencing data generated in this study were deposited in the Sequence Read Archive (SRA) under accession PRJNA521160.\n\n

Published - aem02320-21.pdf

Accepted Version - aem02320-21-acc.pdf

Submitted - 20211123-469799v2full.pdf

Supplemental Material - aem02320-21-s0001.pdf

Supplemental Material - aem02320-21-s0002.xlsx

", "abstract": "Phenazines are a class of bacterially produced redox-active natural antibiotics that have demonstrated potential as a sustainable alternative to traditional pesticides for the biocontrol of fungal crop diseases. However, the prevalence of bacterial resistance to agriculturally relevant phenazines is poorly understood, limiting both the understanding of how these molecules might shape rhizosphere bacterial communities and the ability to perform a risk assessment for off-target effects. Here, we describe profiles of susceptibility to the antifungal agent phenazine-1-carboxylic acid (PCA) across more than 100 bacterial strains isolated from a wheat field where PCA producers are indigenous and abundant. We found that Gram-positive bacteria are typically more sensitive to PCA than Gram-negative bacteria, and there was significant variability in susceptibility both within and across phyla. Phenazine-resistant strains were more likely to be isolated from the wheat rhizosphere, where PCA producers were also more abundant, compared to bulk soil. Furthermore, PCA toxicity was pH-dependent for most susceptible strains and broadly correlated with PCA reduction rates, suggesting that uptake and redox-cycling were important determinants of phenazine toxicity. Our results shed light on which classes of bacteria are most likely to be susceptible to phenazine toxicity in acidic or neutral soils. In addition, the taxonomic and phenotypic diversity of our strain collection represents a valuable resource for future studies on the role of natural antibiotics in shaping wheat rhizosphere communities.", "date": "2022-03", "date_type": "published", "publication": "Applied and Environmental Microbiology", "volume": "88", "number": "6", "publisher": "American Society for Microbiology", "pagerange": "Art. No. e02320-21", "id_number": "CaltechAUTHORS:20211129-175740276", "issn": "0099-2240", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211129-175740276", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0024" }, { "agency": "NIH", "grant_number": "1R01AI127850-01A1" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Doren Family Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1128/aem.02320-21", "pmcid": "PMC8939311", "primary_object": { "basename": "20211123-469799v2full.pdf", "url": "https://authors.library.caltech.edu/records/v9k41-6mf70/files/20211123-469799v2full.pdf" }, "related_objects": [ { "basename": "aem02320-21-acc.pdf", "url": "https://authors.library.caltech.edu/records/v9k41-6mf70/files/aem02320-21-acc.pdf" }, { "basename": "aem02320-21.pdf", "url": "https://authors.library.caltech.edu/records/v9k41-6mf70/files/aem02320-21.pdf" }, { "basename": "aem02320-21-s0001.pdf", "url": "https://authors.library.caltech.edu/records/v9k41-6mf70/files/aem02320-21-s0001.pdf" }, { "basename": "aem02320-21-s0002.xlsx", "url": "https://authors.library.caltech.edu/records/v9k41-6mf70/files/aem02320-21-s0002.xlsx" } ], "pub_year": "2022", "author_list": "Perry, Elena K. and Newman, Dianne K." }, { "id": "https://authors.library.caltech.edu/records/w8jdm-e8b55", "eprint_id": 110383, "eprint_status": "archive", "datestamp": "2023-08-22 14:12:05", "lastmod": "2025-11-21 00:59:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Howland-Michael-F", "name": { "family": "Howland", "given": "Michael F." }, "orcid": "0000-0002-2878-3874" }, { "id": "Dunbar-Oliver-R-A", "name": { "family": "Dunbar", "given": "Oliver R. A." }, "orcid": "0000-0001-7374-0382" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "Parameter Uncertainty Quantification in an Idealized GCM With a Seasonal Cycle", "ispublished": "pub", "full_text_status": "public", "keywords": "uncertainty quantification; Bayesian learning; GCM; seasonal cycle", "note": "\u00a9 2022 The Authors. Journal of Advances in Modeling Earth Systems published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 10 March 2022; Version of Record online: 10 March 2022; Accepted manuscript online: 14 January 2022; Manuscript accepted: 07 January 2022; Manuscript revised: 22 December 2021; Manuscript received: 26 July 2021. \n\nThis work was supported by the generosity of Eric and Wendy Schmidt by recommendation of the Schmidt Futures program and by the National Science Foundation (NSF, award AGS-1835860). The authors thank Andrew Stuart for thoughtful comments on the work and the manuscript. The authors would also like to thank the anonymous referees for their thoughtful comments and contribution to this work. The simulations were performed using resources from the Resnick High Performance Computing Center, which is partially supported by the Gordon and Betty Moore Foundation. \n\nData Availability Statement: All computer code used in this paper is open source. The code is available at (http://doi.org/10.5281/zenodo.5138467). An open-source Julia implementation of CES is accessible at (https://github.com/CliMA/CalibrateEmulateSample.jl).\n\n

Published - J_Adv_Model_Earth_Syst_-_2022_-_Howland_-_Parameter_Uncertainty_Quantification_in_an_Idealized_GCM_With_a_Seasonal_Cycle.pdf

Submitted - essoar.10507655.1.pdf

", "abstract": "Climate models are generally calibrated manually by comparing selected climate statistics, such as the global top-of-atmosphere energy balance, to observations. The manual tuning only targets a limited subset of observational data and parameters. Bayesian calibration can estimate climate model parameters and their uncertainty using a larger fraction of the available data and automatically exploring the parameter space more broadly. In Bayesian learning, it is natural to exploit the seasonal cycle, which has large amplitude compared with anthropogenic climate change in many climate statistics. In this study, we develop methods for the calibration and uncertainty quantification (UQ) of model parameters exploiting the seasonal cycle, and we demonstrate a proof-of-concept with an idealized general circulation model (GCM). UQ is performed using the calibrate-emulate-sample approach, which combines stochastic optimization and machine learning emulation to speed up Bayesian learning. The methods are demonstrated in a perfect-model setting through the calibration and UQ of a convective parameterization in an idealized GCM with a seasonal cycle. Calibration and UQ based on seasonally averaged climate statistics, compared to annually averaged, reduces the calibration error by up to an order of magnitude and narrows the spread of the non-Gaussian posterior distributions by factors between two and five, depending on the variables used for UQ. The reduction in the spread of the parameter posterior distribution leads to a reduction in the uncertainty of climate model predictions.", "date": "2022-03", "date_type": "published", "publication": "Journal of Advances in Modelling Earth Systems", "volume": "14", "number": "3", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021MS002735", "id_number": "CaltechAUTHORS:20210823-173258629", "issn": "1942-2466", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210823-173258629", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Schmidt Futures Program" }, { "agency": "NSF", "grant_number": "AGS-1835860" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021MS002735", "primary_object": { "basename": "essoar.10507655.1.pdf", "url": "https://authors.library.caltech.edu/records/w8jdm-e8b55/files/essoar.10507655.1.pdf" }, "related_objects": [ { "basename": "J_Adv_Model_Earth_Syst_-_2022_-_Howland_-_Parameter_Uncertainty_Quantification_in_an_Idealized_GCM_With_a_Seasonal_Cycle.pdf", "url": "https://authors.library.caltech.edu/records/w8jdm-e8b55/files/J_Adv_Model_Earth_Syst_-_2022_-_Howland_-_Parameter_Uncertainty_Quantification_in_an_Idealized_GCM_With_a_Seasonal_Cycle.pdf" } ], "pub_year": "2022", "author_list": "Howland, Michael F.; Dunbar, Oliver R. A.; et al." }, { "id": "https://authors.library.caltech.edu/records/0t6c2-g9010", "eprint_id": 113232, "eprint_status": "archive", "datestamp": "2023-08-22 13:57:45", "lastmod": "2025-11-21 02:23:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fenwick-Aidan-Q", "name": { "family": "Fenwick", "given": "Aidan Q." }, "orcid": "0000-0003-4442-0878" }, { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Li-Xueqian", "name": { "family": "Li", "given": "Xueqian" }, "orcid": "0000-0002-1197-3743" }, { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Probing the Catalytically Active Region in a Nanoporous Gold Gas Diffusion Electrode for Highly Selective Carbon Dioxide Reduction", "ispublished": "pub", "full_text_status": "public", "keywords": "Gold, Layers, Electrodes, Catalysts, Electrolytes; Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "\u00a9 2022 American Chemical Society. \n\nReceived 17 October 2021. Accepted 30 December 2021. Published online 27 January 2022. \n\nThis work was performed within the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. A.J.W. acknowledges support from the Resnick Sustainability Institute at Caltech for fellowship support and from the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 174530. \n\nAuthor Contributions. A.Q.F. and A.J.W. contributed equally to this work. \n\nAny opinions, findings, and conclusions expressed in this material are those of the authors and do not necessarily reflect those of DOE or NSF. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nz1c02267_si_001.pdf

", "abstract": "We report the use of a nanoporous gold (np-Au) catalyst for CO\u2082 reduction in a gas diffusion electrode (GDE) and characterize the role of wetting in electrochemical performance. The np-Au catalyst has pores on the order of 20 nm and is cross-sectionally isotropic, enabling Faradaic efficiencies for CO of greater than 95% across a wide range of potentials and a maximum partial current density for CO of 168 mA/cm\u00b2. Secondary ion mass spectroscopy and in situ copper underpotential deposition were employed to provide insights into catalyst wetting. At a typical CO\u2082 flow rate of 50 SCCM, approximately half of the catalyst is in contact with the electrolyte during operation, and the dry region exists in the bottom half of the nanoporous catalyst. We discuss implications of the nanoporous GDE wetting characteristics for catalyst performance and the design of improved GDE architectures that can maximize the catalytically active area.", "date": "2022-02-11", "date_type": "published", "publication": "ACS Energy Letters", "volume": "7", "number": "2", "publisher": "American Chemical Society", "pagerange": "871-879", "id_number": "CaltechAUTHORS:20220202-544247000", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220202-544247000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-174530" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.1c02267", "primary_object": { "basename": "nz1c02267_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0t6c2-g9010/files/nz1c02267_si_001.pdf" }, "pub_year": "2022", "author_list": "Fenwick, Aidan Q.; Welch, Alex J.; et al." }, { "id": "https://authors.library.caltech.edu/records/vgd8f-d2r10", "eprint_id": 113896, "eprint_status": "archive", "datestamp": "2023-08-22 13:55:47", "lastmod": "2025-11-21 02:42:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tuia-Devis", "name": { "family": "Tuia", "given": "Devis" }, "orcid": "0000-0003-0374-2459" }, { "id": "Kellenberger-Benjamin", "name": { "family": "Kellenberger", "given": "Benjamin" } }, { "id": "Beery-Sara", "name": { "family": "Beery", "given": "Sara" }, "orcid": "0000-0002-2544-1844" }, { "id": "Costelloe-Blair-R", "name": { "family": "Costelloe", "given": "Blair R." }, "orcid": "0000-0001-5291-788X" }, { "id": "Zuffi-Silvia", "name": { "family": "Zuffi", "given": "Silvia" }, "orcid": "0000-0003-1358-0828" }, { "id": "Risse-Benjamin", "name": { "family": "Risse", "given": "Benjamin" }, "orcid": "0000-0001-5691-4029" }, { "id": "Mathis-Alexander", "name": { "family": "Mathis", "given": "Alexander" }, "orcid": "0000-0002-3777-2202" }, { "id": "Mathis-Mackenzie-W", "name": { "family": "Mathis", "given": "Mackenzie W." }, "orcid": "0000-0001-7368-4456" }, { "id": "van-Langevelde-Frank", "name": { "family": "van Langevelde", "given": "Frank" }, "orcid": "0000-0001-8870-0797" }, { "id": "Burghardt-Tilo", "name": { "family": "Burghardt", "given": "Tilo" } }, { "id": "Kays-Roland", "name": { "family": "Kays", "given": "Roland" }, "orcid": "0000-0002-2947-6665" }, { "id": "Klinck-Holger", "name": { "family": "Klinck", "given": "Holger" } }, { "id": "Wikelski-Martin", "name": { "family": "Wikelski", "given": "Martin" }, "orcid": "0000-0002-9790-7025" }, { "id": "Couzin-Iain-D", "name": { "family": "Couzin", "given": "Iain D." }, "orcid": "0000-0001-8556-4558" }, { "id": "van-Horn-Grant", "name": { "family": "van Horn", "given": "Grant" } }, { "id": "Crofoot-Margaret-C", "name": { "family": "Crofoot", "given": "Margaret C." } }, { "id": "Stewart-Charles-V", "name": { "family": "Stewart", "given": "Charles V." } }, { "id": "Berger-Wolf-Tanya", "name": { "family": "Berger-Wolf", "given": "Tanya" }, "orcid": "0000-0001-7610-1412" } ] }, "title": "Perspectives in machine learning for wildlife conservation", "ispublished": "pub", "full_text_status": "public", "keywords": "Computer science; Conservation biology; General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry", "note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 25 May 2021; Accepted 08 December 2021; Published 09 February 2022. \n\nWe thank Mike Costelloe for assistance with figure design and execution. S.B. would like to thank the Microsoft AI for Earth initiative, the Idaho Department of Fish and Game, and Wildlife Protection Solutions for insightful discussions and providing data for figures. M.C.C. and T.B.W. were supported by the National Science Foundation (IIS 1514174 & IOS 1250895). M.C.C. received additional support from a Packard Foundation Fellowship (2016-65130), and the Alexander von Humboldt Foundation in the framework of the Alexander von Humboldt Professorship endowed by the Federal Ministry of Education and Research. C.V.S. and T.B.W. were supported by the US National Science Foundation (Awards 1453555 and 1550853). S.B. was supported by the National Science Foundation Grant No. 1745301 and the Caltech Resnick Sustainability Institute. I.D.C. acknowledges support from the ONR (N00014-19-1-2556), and I.D.C., B.R.C., M.W., and M.C.C. from, the Deutsche Forschungsgemeinschaft (German Research Foundation) under Germany's Excellence Strategy-EXC 2117-422037984. M.W.M. is the Bertarelli Foundation Chair of Integrative Neuroscience. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the funding agencies. \n\nData availability: Data sharing is not applicable to this article as no datasets were generated or analyzed during the current study. \n\nThese authors contributed equally: Devis Tuia, Benjamin Kellenberger, Sara Beery, Blair R. Costelloe. \n\nContributions: D.T. coordinated the writing team; D.T., B.K., S.B., and B.C. structured and organized the paper with equal contributions; all authors wrote the text; B.C. created the figures. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Aileen Nielsen and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\n

Published - s41467-022-27980-y.pdf

Accepted Version - 2110.12951.pdf

Supplemental Material - 41467_2022_27980_MOESM1_ESM.pdf

", "abstract": "Inexpensive and accessible sensors are accelerating data acquisition in animal ecology. These technologies hold great potential for large-scale ecological understanding, but are limited by current processing approaches which inefficiently distill data into relevant information. We argue that animal ecologists can capitalize on large datasets generated by modern sensors by combining machine learning approaches with domain knowledge. Incorporating machine learning into ecological workflows could improve inputs for ecological models and lead to integrated hybrid modeling tools. This approach will require close interdisciplinary collaboration to ensure the quality of novel approaches and train a new generation of data scientists in ecology and conservation.", "date": "2022-02-09", "date_type": "published", "publication": "Nature Communications", "volume": "13", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 792", "id_number": "CaltechAUTHORS:20220311-169189900", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220311-169189900", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "IIS-1514174" }, { "agency": "NSF", "grant_number": "IOS-1250895" }, { "agency": "David and Lucile Packard Foundation", "grant_number": "2016-65130" }, { "agency": "Alexander von Humboldt Foundation" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)" }, { "agency": "NSF", "grant_number": "CNS-1453555" }, { "agency": "NSF", "grant_number": "EF-1550853" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-19-1-2556" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "EXC 2117-422037984" }, { "agency": "Bertarelli Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-022-27980-y", "primary_object": { "basename": "41467_2022_27980_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/vgd8f-d2r10/files/41467_2022_27980_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41467-022-27980-y.pdf", "url": "https://authors.library.caltech.edu/records/vgd8f-d2r10/files/s41467-022-27980-y.pdf" }, { "basename": "2110.12951.pdf", "url": "https://authors.library.caltech.edu/records/vgd8f-d2r10/files/2110.12951.pdf" } ], "pub_year": "2022", "author_list": "Tuia, Devis; Kellenberger, Benjamin; et al." }, { "id": "https://authors.library.caltech.edu/records/30sbp-5t747", "eprint_id": 113094, "eprint_status": "archive", "datestamp": "2023-08-22 13:55:01", "lastmod": "2025-11-20 18:58:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Larsson-Henrik-R", "name": { "family": "Larsson", "given": "Henrik R." }, "orcid": "0000-0002-9417-1518" }, { "id": "Zhai-Huanchen", "name": { "family": "Zhai", "given": "Huanchen" }, "orcid": "0000-0003-0086-0388" }, { "id": "Gunst-Klaas", "name": { "family": "Gunst", "given": "Klaas" }, "orcid": "0000-0003-2537-7632" }, { "id": "Chan-Garnet-K-L", "name": { "family": "Chan", "given": "Garnet Kin-Lic" }, "orcid": "0000-0001-8009-6038" } ] }, "title": "Matrix Product States with Large Sites", "ispublished": "pub", "full_text_status": "public", "keywords": "Wave function, Energy, Mathematical methods, Cluster chemistry, Hamiltonians; Physical and Theoretical Chemistry; Computer Science Applications", "note": "\u00a9 2022 American Chemical Society. \n\nReceived 22 September 2021. Published online 21 January 2022. \n\nWe thank Cyrus Umrigar for providing us with the SHCI PEC data for the chromium dimer. Work by G.K.C. was supported by the US National Science Foundation (NSF) via Grant CHE-2102505. G.K.C. acknowledges additional support from the Simons Foundation via the Many-Electron Collaboration and the Investigator Award. Work by H.Z. was supported by the US Department of Energy, Office of Science, Basic Energy Sciences under Award DE-SC0019374. Work by H.R.L. was supported by the Air Force Office of Scientific Research, under Award FA9550-18-1-0095. H.R.L. acknowledges support from a postdoctoral fellowship from the German Research Foundation (DFG) via Grant LA 4442/1-1 during the first part of this work. K.G. acknowledges support from a Ph.D. fellowship and a travel grant for a long stay abroad at the California Institute of Technology from the Research Foundation Flanders (FWO Vlaanderen). Some of the computations presented here were conducted at the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. \n\nThe authors declare the following competing financial interest(s): G.K.C. is a part owner of QSimulate, Inc.\n\n

Accepted Version - 2109.11036.pdf

Supplemental Material - ct1c00957_si_001.pdf

", "abstract": "We explore various ways to group orbitals into clusters in a matrix product state (MPS). We explain how a generic cluster MPS can often lead to an increase in computational cost and instead propose a special cluster structure, involving only the first and last orbitals/sites, with a wider scope for computational advantage. This structure is a natural formalism to describe correlated multireference (MR) theories. We demonstrate the flexibility and usefulness of this approach by implementing various uncontracted MR configuration interaction, perturbation, and linearized coupled cluster theories using an MPS with large cluster sites. Applications to the nitrogen dimer, the chromium dimer, and benzene, including up to triple excitations in the external space, demonstrate the utility of an MPS with up to two large sites. We use our results to analyze the quality of different multireference approximations.", "date": "2022-02-08", "date_type": "published", "publication": "Journal of Chemical Theory and Computation", "volume": "18", "number": "2", "publisher": "American Chemical Society", "pagerange": "749-762", "id_number": "CaltechAUTHORS:20220125-893621641", "issn": "1549-9618", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220125-893621641", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-2102505" }, { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019374" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0095" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "LA 4442/1-1" }, { "agency": "Fonds Wetenschappelijk Onderzoek (FWO)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jctc.1c00957", "primary_object": { "basename": "2109.11036.pdf", "url": "https://authors.library.caltech.edu/records/30sbp-5t747/files/2109.11036.pdf" }, "related_objects": [ { "basename": "ct1c00957_si_001.pdf", "url": "https://authors.library.caltech.edu/records/30sbp-5t747/files/ct1c00957_si_001.pdf" } ], "pub_year": "2022", "author_list": "Larsson, Henrik R.; Zhai, Huanchen; et al." }, { "id": "https://authors.library.caltech.edu/records/w13hs-epf82", "eprint_id": 112248, "eprint_status": "archive", "datestamp": "2023-08-22 13:34:31", "lastmod": "2025-11-20 21:16:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jongaramrungruang-Siraput", "name": { "family": "Jongaramrungruang", "given": "Siraput" }, "orcid": "0000-0002-2477-2043" }, { "id": "Thorpe-Andrew-K", "name": { "family": "Thorpe", "given": "Andrew K." }, "orcid": "0000-0001-7968-5433" }, { "id": "Matheou-Georgios", "name": { "family": "Matheou", "given": "Georgios" }, "orcid": "0000-0003-4024-4571" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "MethaNet \u2013 An AI-driven approach to quantifying methane point-source emission from high-resolution 2-D plume imagery", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Methane gas; Methane detection; Methane quantification; Deep learning; Point-source emission; Regional budget; AVIRIS-NG; Greenhouse gas; LES; CNN; Computers in Earth Sciences; Geology; Soil Science", "note": "\u00a9 2021 Elsevier. \n\nReceived 12 March 2021, Revised 1 October 2021, Accepted 14 November 2021, Available online 4 December 2021. \n\nThis work is part of SJ's NASA Earth and Space Science Fellowship (NESSF, grant no. 80NSSC18K1350). We acknowledge the Resnick Sustainability Institute at Caltech for their kind support with computing resources. This work was supported in part by NASA's Carbon Monitoring System (CMS) Prototype Methane Monitoring System for California. We thank the AVIRIS-NG team and colleagues at the Pacific Gas and Electric Company for their support for controlled-release experiments. \n\nDescription of author's responsibilities. SJ designed the research objectives, performed the analysis, and wrote the paper. GM ran the LES model, and provided output. AT provided the AVIRIS-NG datasets and supported the writing. CF provided guidance and support on scientific approaches and experimental setups, and advised the writing of this paper. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.", "abstract": "Methane is one of the most important anthropogenic greenhouse gases with a significant impact on the Earth's radiation budget and tropospheric background ozone. Despite a well-constrained global budget, quantification of local and regional methane emissions has proven challenging. Recent advancements in airborne remote sensing instruments such as from the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) provide 2-D observations of CH\u2084 plume column enhancements at an unprecedented resolution of 1\u20135 m over large geographic areas. Quantifying an emission rate from observed plumes is a critical step for understanding local emission distributions and prioritizing mitigation efforts. However, there exists no method that can predict emission rates from detected plumes in real-time without ancillary data reliably. In order to predict methane point-source emissions directly from high resolution 2-D plume images without relying on other local measurements such as background wind speeds, we trained a convolutional neural network model called MethaNet. The training data was derived from large eddy simulations of methane plumes and realistic measurement noise over agricultural, desert and urban environments. Our model has a mean absolute percentage error for predicting unseen plumes under 17%, a significant improvement from previous methods that require wind information. Using MethaNet, a validation against a natural gas controlled-release experiment agrees to within the precision error estimate. Our results support the basis for the applicability of using deep learning techniques to quantify CH\u2084 point sources in an automated manner over large geographical areas, not only for present and future airborne field campaigns but also for upcoming space-based observations in this decade.", "date": "2022-02", "date_type": "published", "publication": "Remote Sensing of Environment", "volume": "269", "publisher": "Elsevier", "pagerange": "Art. No. 112809", "id_number": "CaltechAUTHORS:20211207-393219000", "issn": "0034-4257", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211207-393219000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Earth and Space Science Fellowship", "grant_number": "80NSSC18K1350" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.rse.2021.112809", "pub_year": "2022", "author_list": "Jongaramrungruang, Siraput; Thorpe, Andrew K.; et al." }, { "id": "https://authors.library.caltech.edu/records/15mk0-g2025", "eprint_id": 115716, "eprint_status": "archive", "datestamp": "2023-08-22 13:48:38", "lastmod": "2025-11-20 18:16:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wilson-Earle-A", "name": { "family": "Wilson", "given": "Earle A." }, "orcid": "0000-0003-2329-5115" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "id": "Stewart-A-L", "name": { "family": "Stewart", "given": "Andrew L." }, "orcid": "0000-0001-5861-4070" }, { "id": "Sun-Shantong", "name": { "family": "Sun", "given": "Shantong" }, "orcid": "0000-0002-6932-5589" } ] }, "title": "Bathymetric Control of Subpolar Gyres and the Overturning Circulation in the Southern Ocean", "ispublished": "pub", "full_text_status": "public", "keywords": "Southern Ocean; Eddies; Ocean dynamics; Gyres; General circulation models; Idealized models; Oceanography", "note": "\u00a9 2022 American Meteorological Society. \n\n(Manuscript received 1 July 2021, in final form 11 November 2021) \n\nEAW, AFT, and SS were supported by NSF Awards OCE-1756956 and OPP-2023259. EAW also acknowledges support from Caltech's Terrestrial Hazard Observations and Reporting (THOR) Center. ALS was supported by NSF Award OPP-2023244. Numerical simulations were carried out at the Resnick High Performance Computing Center at Caltech. The authors graciously thank the MITgcm modelling team for their invaluable efforts. The authors also thank two anonymous reviewers for their insightful and constructive feedback, which substantially improved this manuscript. \n\nData availability statement. Source code for MITgcm is available at https://github.com/MITgcm/. The version of MITgcm used in this study is archived at https://doi.org/10.5281/zenodo.1409237. Input files for the MITgcm runs described in this study are archived at https://doi.org/10.5281/zenodo.5057219. Hydrographic sections of the Weddell Sea collected by the R/V Polarstern on the 1992 ANT/X cruise are available at https://cchdo.ucsd.edu/cruise/06AQANTX_4. Southern Ocean Bathymetry data were compiled and made available by the GEBCO Bathymetric Compilation Group 2020, which may be retrieved at https://doi.org/10/dtg3. \n\nPublisher's Note: This article was revised on 28 February 2022 to include better resolution versions of Figs. 7, 11, and 12.\n\n

Published - _15200485_-_Journal_of_Physical_Oceanography__Bathymetric_Control_of_Subpolar_Gyres_and_the_Overturning_Circulation_in_the_Southern_Ocean.pdf

", "abstract": "The subpolar gyres of the Southern Ocean form an important dynamical link between the Antarctic Circumpolar Current (ACC) and the coastline of Antarctica. Despite their key involvement in the production and export of bottom water and the poleward transport of oceanic heat, these gyres are rarely acknowledged in conceptual models of the Southern Ocean circulation, which tend to focus on the zonally averaged overturning across the ACC. To isolate the effect of these gyres on the regional circulation, we carried out a set of numerical simulations with idealized representations of the Weddell Sea sector in the Southern Ocean. A key result is that the zonally oriented submarine ridge along the northern periphery of the subpolar gyre plays a fundamental role in setting the stratification and circulation across the entire region. In addition to sharpening and strengthening the horizontal circulation of the gyre, the zonal ridge establishes a strong meridional density front that separates the weakly stratified subpolar gyre from the more stratified circumpolar flow. Critically, the formation of this front shifts the latitudinal outcrop position of certain deep isopycnals such that they experience different buoyancy forcing at the surface. Additionally, the zonal ridge modifies the mechanisms by which heat is transported poleward by the ocean, favoring heat transport by transient eddies while suppressing that by stationary eddies. This study highlights the need to characterize how bathymetry at the subpolar gyre\u2013ACC boundary may constrain the transient response of the regional circulation to changes in surface forcing.\n\nSignificance Statement:\nThis study explores the impact of seafloor bathymetry on the dynamics of subpolar gyres in the Southern Ocean. The subpolar gyres are major circulation features that connect the Antarctic Circumpolar Current (ACC) and the coastline of Antarctica. This work provides deeper insight for how the submarine ridges that exist along the northern periphery of these gyres shape the vertical distribution of tracers and overturning circulation in these regions. These findings highlight an underappreciated yet fundamentally important topographical constraint on the three-dimensional cycling of heat and carbon in the Southern Ocean\u2014processes that have far-reaching implications for the global climate. Future work should explore how the presence of these ridges affect the time-evolving response of the Southern Ocean to changes in surface conditions.", "date": "2022-02", "date_type": "published", "publication": "Journal of Physical Oceanography", "volume": "52", "number": "2", "publisher": "American Meteorological Society", "pagerange": "205-223", "id_number": "CaltechAUTHORS:20220721-7922000", "issn": "0022-3670", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220721-7922000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OCE-1756956" }, { "agency": "NSF", "grant_number": "OPP-2023259" }, { "agency": "Caltech Terrestrial Hazard Observation and Reporting (THOR) Center" }, { "agency": "NSF", "grant_number": "OPP-2023244" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/jpo-d-21-0136.1", "primary_object": { "basename": "_15200485_-_Journal_of_Physical_Oceanography__Bathymetric_Control_of_Subpolar_Gyres_and_the_Overturning_Circulation_in_the_Southern_Ocean.pdf", "url": "https://authors.library.caltech.edu/records/15mk0-g2025/files/_15200485_-_Journal_of_Physical_Oceanography__Bathymetric_Control_of_Subpolar_Gyres_and_the_Overturning_Circulation_in_the_Southern_Ocean.pdf" }, "pub_year": "2022", "author_list": "Wilson, Earle A.; Thompson, Andrew F.; et al." }, { "id": "https://authors.library.caltech.edu/records/8rxt3-fyb77", "eprint_id": 112285, "eprint_status": "archive", "datestamp": "2023-08-22 13:27:30", "lastmod": "2025-11-21 01:50:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dahlstrom-Kurt-M", "name": { "family": "Dahlstrom", "given": "Kurt M." }, "orcid": "0000-0001-6590-6020" }, { "id": "Newman-D-K", "name": { "family": "Newman", "given": "Dianne K." }, "orcid": "0000-0003-1647-1918" } ] }, "title": "Soil bacteria protect fungi from phenazines by acting as toxin sponges", "ispublished": "pub", "full_text_status": "public", "keywords": "phenazines; bacteria; fungi; protective partnership; microbial interactions; inter-kingdom; rhizosphere; community; General Agricultural and Biological Sciences; General Biochemistry, Genetics and Molecular Biology", "note": "\u00a9 2021 Elsevier Inc. \n\nReceived 28 March 2021, Revised 12 August 2021, Accepted 1 November 2021, Available online 22 November 2021. \n\nWe thank members of the Newman lab for constructive feedback on the project and the manuscript and The Millard and Muriel Jacobs Genetics and Genomics Laboratory at Caltech and Igor Antoshechkin for support during library preparation and sequencing. We thank Marko Kojic for help screening transposon mutants, as well as Robert Cramer, Deborah Hogan, and Jeff Holloman for sharing their expertise in mycology. We thank Susan Duffy for skillful instruction in biology and the belief that substantial goals are achievable when we work together. This work was supported by the Life Sciences Research Foundation (postdoctoral fellowship to K.M.D.), the Resnick Sustainability Institute (K.M.D. and D.K.N.), and the NIH (1R01AI127850-01A1 to D.K.N.). The ORCIDs for this article are as follows: 0000-0001-6590-6020 (K.M.D.) and 0000-0003-1647-1918 (D.K.N.). \n\nAuthor contributions. K.M.D. performed the experiments and wrote the original draft. D.K.N. supervised the project. K.M.D. and D.K.N. designed the research strategy, analyzed data, acquired funding for the project, and re-wrote, reviewed, and edited the paper. \n\nDeclaration of interests. The authors have filed a provisional patent (CIT-8617-P) \"Biocontrol strain to protect fungi from phenazine antibiotics\" based on this work.\n\nData and code availability.\nGenomic data generated in this study to characterize the co-isolated Aspergillus species and P. edwinii, and used to generate in-frame deletions for P. edwinii, have been deposited with GenBank under accession numbers Genbank: JAHXQV000000000 (Aspergillus whole genome shotgun sequence) and Genbank: CP080095-CP080096 (full chromosomes for P. edwinii) and are available as of the date of publication. This study does not report any original code. Microscopy data reported in this paper will be shared by the lead contact upon request, and any additional information required to reanalyze the data reported in this paper is available from the lead contact upon request.\n\n

Supplemental Material - 1-s2.0-S0960982221015232-mmc1.pdf

", "abstract": "Many environmentally and clinically important fungi are sensitive to toxic, bacterially produced, redox-active molecules called phenazines. Despite being vulnerable to phenazine assault, fungi inhabit microbial communities that contain phenazine producers. Because many fungi cannot withstand phenazine challenge but some bacterial species can, we hypothesized that bacterial partners may protect fungi in phenazine-replete environments. From a single soil sample, we were able to co-isolate several such physically associated pairings. We discovered the novel species Paraburkholderia edwinii and demonstrated it can protect a co-isolated Aspergillus species from phenazine-1-carboxylic acid (PCA) by sequestering it, acting as a toxin sponge; in turn, it also gains protection. When challenged with PCA, P. edwinii changes its morphology, forming aggregates within the growing fungal colony. Further, the fungal partner triggers P. edwinii to sequester PCA and maintains conditions that limit PCA toxicity by promoting an anoxic and highly reducing environment. A mutagenic screen of P. edwinii revealed this protective program depends on the stress-inducible transcriptional repressor HrcA. We show that one relevant stressor in response to PCA challenge is fungal acidification and that acid stress causes P. edwinii to behave as though the fungus were present. Finally, we reveal this phenomenon as widespread among Paraburkholderia with moderate specificity among bacterial and fungal partners, including plant and human pathogens. Our discovery suggests a common mechanism by which fungi can gain access to phenazine-replete environments and provides a tractable model system for its study. These results have implications for how microbial communities in the rhizosphere as well as in plant and human infection sites negotiate community membership via a chemical dialectic.", "date": "2022-01-24", "date_type": "published", "publication": "Current Biology", "volume": "32", "number": "2", "publisher": "Cell Press", "pagerange": "275-288", "id_number": "CaltechAUTHORS:20211208-560304000", "issn": "0960-9822", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211208-560304000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Life Sciences Research Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "1R01AI127850-01A1" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1016/j.cub.2021.11.002", "primary_object": { "basename": "1-s2.0-S0960982221015232-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/8rxt3-fyb77/files/1-s2.0-S0960982221015232-mmc1.pdf" }, "pub_year": "2022", "author_list": "Dahlstrom, Kurt M. and Newman, Dianne K." }, { "id": "https://authors.library.caltech.edu/records/m7qr1-12e11", "eprint_id": 122535, "eprint_status": "archive", "datestamp": "2023-08-22 13:27:20", "lastmod": "2025-11-20 22:51:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ginsberg-Leah", "name": { "family": "Ginsberg", "given": "Leah" }, "orcid": "0000-0001-9685-7014" }, { "id": "McDonald-Robin", "name": { "family": "McDonald", "given": "Robin" } }, { "id": "Lin-Qinchen", "name": { "family": "Lin", "given": "Qinchen" } }, { "id": "Hendrickx-Rodinde", "name": { "family": "Hendrickx", "given": "Rodinde" }, "orcid": "0000-0001-7161-4526" }, { "id": "Spigolon-Giada", "name": { "family": "Spigolon", "given": "Giada" }, "orcid": "0000-0002-1704-8372" }, { "id": "Ravichandran-G", "name": { "family": "Ravichandran", "given": "Guruswami" }, "orcid": "0000-0002-2912-0001" }, { "id": "Daraio-C", "name": { "family": "Daraio", "given": "Chiara" }, "orcid": "0000-0001-5296-4440" }, { "id": "Roumeli-Eleftheria", "name": { "family": "Roumeli", "given": "Eleftheria" }, "orcid": "0000-0002-2828-1428" } ] }, "title": "Cell wall and cytoskeletal contributions in single cell biomechanics of Nicotiana tabacum", "ispublished": "pub", "full_text_status": "public", "keywords": "Religious studies; Cultural Studies", "note": "\u00a9 The Author(s), 2022. Published by Cambridge University Press in association with The John Innes Centre. This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nThe authors thank Dr. Wai Pang Chan for obtaining confocal microscopy images, Dr. Takato Imaizumi, Dr. Josep Vilarrasa-Blasi and Dr. Luca Bonanomi for the helpful discussions. \n\nThis work was supported by the University of Washington (E.R.); and the Resnick Sustainability Institute at Caltech (C.D.). \n\nAuthorship contributions: E.R., L.G. and C.D. conceived and designed the study. E.R., L.G., R.M., Q.L. and G.S. conducted data gathering. E.R. and R.H. maintained the cell lines. L.G. performed data analyses and statistical analyses. E.R. and L.G. wrote the article and all authors edited it. \n\nNo conflicts of interest declared.\n\n

Published - cell-wall-and-cytoskeletal-contributions-in-single-cell-biomechanics-of-nicotiana-tabacum.pdf

Supplemental Material - S2632882821000151sup0001.docx

", "abstract": "Studies on the mechanics of plant cells usually focus on understanding the effects of turgor pressure and properties of the cell wall (CW). While the functional roles of the underlying cytoskeleton have been studied, the extent to which it contributes to the mechanical properties of cells is not elucidated. Here, we study the contributions of the CW, microtubules (MTs) and actin filaments (AFs), in the mechanical properties of Nicotiana tabacum cells. We use a multiscale biomechanical assay comprised of atomic force microscopy and micro-indentation in solutions that (i) remove MTs and AFs and (ii) alter osmotic pressures in the cells. To compare measurements obtained by the two mechanical tests, we develop two generative statistical models to describe the cell's behaviour using one or both datasets. Our results illustrate that MTs and AFs contribute significantly to cell stiffness and dissipated energy, while confirming the dominant role of turgor pressure.", "date": "2022-01-22", "date_type": "published", "publication": "Quantitative Plant Biology", "volume": "3", "publisher": "Cambridge University Press", "pagerange": "e1", "id_number": "CaltechAUTHORS:20230725-706639000.52", "issn": "2632-8828", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230725-706639000.52", "funders": { "items": [ { "agency": "University of Washington" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1017/qpb.2021.15", "pmcid": "PMC10097588", "primary_object": { "basename": "cell-wall-and-cytoskeletal-contributions-in-single-cell-biomechanics-of-nicotiana-tabacum.pdf", "url": "https://authors.library.caltech.edu/records/m7qr1-12e11/files/cell-wall-and-cytoskeletal-contributions-in-single-cell-biomechanics-of-nicotiana-tabacum.pdf" }, "related_objects": [ { "basename": "S2632882821000151sup0001.docx", "url": "https://authors.library.caltech.edu/records/m7qr1-12e11/files/S2632882821000151sup0001.docx" } ], "pub_year": "2022", "author_list": "Ginsberg, Leah; McDonald, Robin; et al." }, { "id": "https://authors.library.caltech.edu/records/2b84f-9tc42", "eprint_id": 112847, "eprint_status": "archive", "datestamp": "2023-09-22 22:32:33", "lastmod": "2025-11-20 21:46:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Samkian-Adrian-E", "name": { "family": "Samkian", "given": "Adrian E." }, "orcid": "0000-0002-0068-3572" }, { "id": "Sercel-Zachary-P", "name": { "family": "Sercel", "given": "Zachary P." } }, { "id": "Virgil-Scott-C", "name": { "family": "Virgil", "given": "Scott C." }, "orcid": "0000-0001-8586-5641" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Some unusual transformations of a highly reactive \u03b1-bromocaranone", "ispublished": "pub", "full_text_status": "public", "keywords": "Carene; Ring fragmentation; Chiral building blocks; Terpenes; Organic Chemistry; Drug Discovery; Biochemistry", "note": "\u00a9 2021 Published by Elsevier. \n\nReceived 6 September 2021, Revised 14 October 2021, Accepted 18 October 2021, Available online 22 October 2021. \n\nWe gratefully acknowledge the National Science Foundation (Grant CHE-1800511) for financial support. Z.P.S. thanks the National Science Foundation for a predoctoral fellowship. The computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. Chiral SFC analysis and preparatory HPLC were performed with instrumentation at the Caltech Center for Catalysis and Chemical Synthesis, a facility of the Beckman Institute at Caltech. High resolution mass spectrometry was performed on an instrument funded by DOW Next Generation Instrument Funds. We thank Alexander Q. Cusumano (Caltech) for assistance with DFT calculations as well as helpful discussions. We thank Dr. Dave VanderVelde (Caltech) for NMR expertise, and Dr. Mona Shahgoli (Caltech) for HRMS data acquisition. This manuscript is dedicated to our friend and colleague Professor Steve Martin in special recognition of his dedication to the Tetrahedron family of journals.\n\nDeclaration of Competing Interest:\nThe authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Brian M. Stoltz reports financial support was provided by National Science Foundation. I, Brian M. Stoltz am Editor in Chief of Tetrahedron, the sister journal to which we are submitting.\n\n

Supplemental Material - 1-s2.0-S004040392100784X-mmc1.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc10.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc11.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc12.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc13.pdf

Supplemental Material - 1-s2.0-S004040392100784X-mmc14.xlsx

Supplemental Material - 1-s2.0-S004040392100784X-mmc2.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc3.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc4.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc5.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc6.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc7.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc8.zip

Supplemental Material - 1-s2.0-S004040392100784X-mmc9.zip

", "abstract": "The facile synthesis of a highly reactive \u03b1-bromocaranone from (+)-carene is reported. This intermediate was found to generate diverse chiral building blocks through radical or carbocation mediated cyclopropyl fragmentation reactions in moderate to excellent yields. Furthermore, the formation of an unexpected carvone derivative prompted several control studies that provided mechanistic insight into an unusual transformation. This study not only demonstrates the synthesis of a variety of chiral building blocks but provides insight into the reactivity of keto-halo-cyclopropanes in general.", "date": "2022-01-19", "date_type": "published", "publication": "Tetrahedron Letters", "volume": "89", "publisher": "Elsevier", "pagerange": "Art. No. 153496", "id_number": "CaltechAUTHORS:20220112-698034937", "issn": "0040-4039", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220112-698034937", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1800511" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "DOW Next Generation Instrument Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.tetlet.2021.153496", "primary_object": { "basename": "1-s2.0-S004040392100784X-mmc6.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc6.zip" }, "related_objects": [ { "basename": "1-s2.0-S004040392100784X-mmc7.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc7.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc13.pdf", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc13.pdf" }, { "basename": "1-s2.0-S004040392100784X-mmc14.xlsx", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc14.xlsx" }, { "basename": "1-s2.0-S004040392100784X-mmc1.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc1.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc2.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc2.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc3.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc3.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc5.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc5.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc8.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc8.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc9.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc9.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc10.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc10.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc11.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc11.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc12.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc12.zip" }, { "basename": "1-s2.0-S004040392100784X-mmc4.zip", "url": "https://authors.library.caltech.edu/records/2b84f-9tc42/files/1-s2.0-S004040392100784X-mmc4.zip" } ], "pub_year": "2022", "author_list": "Samkian, Adrian E.; Sercel, Zachary P.; et al." }, { "id": "https://authors.library.caltech.edu/records/tpyet-es292", "eprint_id": 115186, "eprint_status": "archive", "datestamp": "2023-09-15 07:39:57", "lastmod": "2025-11-20 18:46:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Shantong", "name": { "family": "Sun", "given": "Shantong" }, "orcid": "0000-0002-6932-5589" }, { "id": "Thompson-A-F", "name": { "family": "Thompson", "given": "Andrew F." }, "orcid": "0000-0003-0322-4811" }, { "id": "Xie-Shang-Ping", "name": { "family": "Xie", "given": "Shang-Ping" } }, { "id": "Long-Shang-Min", "name": { "family": "Long", "given": "Shang-Min" } } ] }, "title": "Indo-Pacific Warming Induced by a Weakening of the Atlantic Meridional Overturning Circulation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Meridional overturning circulation; Climate change; General circulation models; Atmospheric Science", "note": "\u00a9 2021 American Meteorological Society.\n\nManuscript received 30 April 2021, in final form 24 October 2021.\n\nWithout implying their endorsement, we thank Emily Newsom, Laure Zanna, Spencer Jones, and Dave Bonan for helpful discussions. We are also grateful for constructive comments from Christopher Wolfe and two anonymous reviewers that helped to improve this manuscript. SS and AFT were supported by NSF Award OCE-1756956 and the David and Lucille Packard Foundation. SL acknowledges support from the National Natural Science Foundation of China (42076208 and 41706026). The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology.\n\nData availability statement:\nThe CCSM4 model output was downloaded from the Climate Data Gateway at NCAR (https://www.earthsystemgrid.org). The code for reproducing the MITgcm ocean-only simulations is provided at the online open access repository, figshare (https://doi.org/10.6084/m9.figshare.16308111).", "abstract": "The reorganization of the Atlantic meridional overturning circulation (AMOC) is often associated with changes in Earth's climate. These AMOC changes are communicated to the Indo-Pacific basins via wave processes and induce an overturning circulation anomaly that opposes the Atlantic changes on decadal to centennial time scales. We examine the role of this transient, interbasin overturning response, driven by an AMOC weakening, both in an ocean-only model with idealized geometry and in a coupled CO\u2082 quadrupling experiment, in which the ocean warms on two distinct time scales: a fast decadal surface warming and a slow centennial subsurface warming. We show that the transient interbasin overturning produces a zonal heat redistribution between the Atlantic and Indo-Pacific basins. Following a weakened AMOC, an anomalous northward heat transport emerges in the Indo-Pacific, which substantially compensates for the Atlantic southward heat transport anomaly. This zonal heat redistribution manifests as a thermal interbasin seesaw between the high-latitude North Atlantic and the subsurface Indo-Pacific and helps to explain why Antarctic temperature records generally show more gradual changes than the Northern Hemisphere during the last glacial period. In the coupled CO\u2082 quadrupling experiment, we find that the interbasin heat transport due to a weakened AMOC contributes substantially to the slow centennial subsurface warming in the Indo-Pacific, accounting for more than half of the heat content increase and sea level rise. Thus, our results suggest that the transient interbasin overturning circulation is a key component of the global ocean heat budget in a changing climate.", "date": "2022-01-15", "date_type": "published", "publication": "Journal of Climate", "volume": "35", "number": "2", "publisher": "American Meteorological Society", "pagerange": "815-832", "id_number": "CaltechAUTHORS:20220616-652525900", "issn": "0894-8755", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220616-652525900", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OCE-1756956" }, { "agency": "David and Lucile Packard Foundation" }, { "agency": "National Natural Science Foundation of China", "grant_number": "42076208" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41706026" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/jcli-d-21-0346.1", "pub_year": "2022", "author_list": "Sun, Shantong; Thompson, Andrew F.; et al." }, { "id": "https://authors.library.caltech.edu/records/jemmb-kp969", "eprint_id": 112181, "eprint_status": "archive", "datestamp": "2023-08-22 13:18:51", "lastmod": "2025-11-20 21:52:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Yacong-Brooke", "name": { "family": "Zhou", "given": "Yacong (Brooke)" }, "orcid": "0000-0001-9496-9565" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A." }, "orcid": "0000-0003-0097-5716" }, { "id": "Asimow-P-D", "name": { "family": "Asimow", "given": "Paul D." }, "orcid": "0000-0001-6025-8925" } ] }, "title": "An internal energy-dependent model for the Gr\u00fcneisen parameter of silicate liquids", "ispublished": "pub", "full_text_status": "public", "keywords": "Molecular dynamics; Silicate liquids; Gr\u00fcneisen parameter; Equation of state; Geochemistry and Petrology", "note": "\u00a9 2021 Elsevier. \n\nReceived 22 March 2021; accepted in revised form 4 October 2021; available online 13 October 2021. \n\nThis work is funded by the Office of Naval Research, award numbers N00014-20\u20131-2603 (to PDA) and N00014-19\u20131-2081 (to WAG), and by the National Science Foundation, award number 1725349. The computations presented here were conducted in the Resnick High Performance Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. \n\nResearch Data associated with this article (the V-P-E simulation points shown in Fig. 1, Fig. 3) can be accessed at the CaltechDATA repository at https://doi.org/10.22002/D1.1921. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\n

Supplemental Material - 1-s2.0-S0016703721005949-mmc1.pdf

", "abstract": "We investigated the accuracy of the Mie-Gr\u00fcneisen approximation, which treats the Gr\u00fcneisen parameter (\u03b3) as a one-parameter function of volume, for use in describing the thermal equation of state of a silicate liquid. For this study, we focused on a single composition: the diopside-anorthite eutectic, an Fe-free basalt analog that has been extensively studied by shock wave experiments. We tuned an empirical force-field to a small set of ab initio N-V-T molecular dynamics simulations to ensure that it reproduces pressure, heat capacity, and at high and low pressures. We then used empirical force-field molecular dynamics simulations in a larger system and for longer run times to ensure accurate extraction of at numerous N-V-E state points. To first order, the results show the expected volume-dependence for silicate liquids, with increasing as volume decreases. However, there are also significant and systematic variations of with internal energy (E) at constant volume. We propose a simple model form that captures the volume and E dependence of with only one more free parameter than a typical Mie-Gr\u00fcneisen formulation. We demonstrate the utility of this new model for well-constrained fitting to sparse shock wave experiment data below 200 GPa, obtaining a marked improvement in the ability to simultaneously fit the pre-heated liquid Hugoniot and points substantially offset from this Hugoniot.", "date": "2022-01-01", "date_type": "published", "publication": "Geochimica et Cosmochimica Acta", "volume": "316", "publisher": "Elsevier", "pagerange": "59-68", "id_number": "CaltechAUTHORS:20211202-191331622", "issn": "0016-7037", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211202-191331622", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-20-1-2603" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-19-1-2081" }, { "agency": "NSF", "grant_number": "EAR-1725349" }, { "agency": "Resnick Sustainability Institute" } ] }, "other_numbering_system": { "items": [ { "id": "1501", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.gca.2021.10.005", "primary_object": { "basename": "1-s2.0-S0016703721005949-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/jemmb-kp969/files/1-s2.0-S0016703721005949-mmc1.pdf" }, "pub_year": "2022", "author_list": "Zhou, Yacong (Brooke); Goddard, William A.; et al." }, { "id": "https://authors.library.caltech.edu/records/4s279-h0c90", "eprint_id": 111835, "eprint_status": "archive", "datestamp": "2023-08-22 13:18:24", "lastmod": "2025-11-20 22:04:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kipp-Michael-A", "name": { "family": "Kipp", "given": "Michael A." }, "orcid": "0000-0003-1844-3670" }, { "id": "Tissot-F-L-H", "name": { "family": "Tissot", "given": "Fran\u00e7ois L. H." }, "orcid": "0000-0001-6622-2907" } ] }, "title": "Inverse methods for consistent quantification of seafloor anoxia using uranium isotope data from marine sediments", "ispublished": "pub", "full_text_status": "public", "keywords": "paleoredox; isotope mass balance; Bayesian inference; MCMC; carbonate", "note": "\u00a9 2021 Elsevier B.V. \n\nReceived 2 January 2021, Revised 30 August 2021, Accepted 6 October 2021, Available online 3 November 2021. \n\nThis manuscript benefitted from the insightful comments of Kimberly Lau, Chris Reinhard, an anonymous reviewer, and Editors Lou Derry and Laurence Coogan. We also thank Joshua Krissansen-Totton and Jess Adkins for helpful discussions. Some of the computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. This work was supported by a Postdoctoral Fellowship in Geobiology from the Agouron Institute to MAK, and NSF grants EAR-1824002 and MGG-2054892, and start-up funds (provided by Caltech) to FLHT. \n\nCRediT authorship contribution statement: Michael A. Kipp: Conceptualization, Methodology, Software, Writing \u2013 original draft. Fran\u00e7ois L.H. Tissot: Conceptualization, Methodology, Writing \u2013 review & editing. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\n

Supplemental Material - 1-s2.0-S0012821X21004969-mmc1.pdf

", "abstract": "Uranium isotopes (\u03b4\u00b2\u00b3\u2078U) have quickly become one of the most widely-used redox proxies in paleoceanographic studies. The quantitative power of the \u03b4\u00b2\u00b3\u2078U proxy derives from the long marine residence time of uranium and the dominance of reduction in fractionating uranium isotopes during removal from seawater. The seawater \u03b4\u00b2\u00b3\u2078U value is therefore sensitive to the size of the anoxic sink, and by extension, the area of the seafloor overlain by anoxic waters. Leveraging the ability of carbonates to record and retain the seawater \u03b4\u00b2\u00b3\u2078U value, and the ubiquity of carbonate sediments in the geologic record, numerous studies have quantified seafloor anoxia across ocean anoxic events, mass extinctions, and global climatic changes. In most cases, forward models of marine uranium isotope mass balance have been used, illustrating potential histories of seafloor anoxia during these events.\nHere we show that there are multiple ways in which such forward modeling can lead to spurious inferences of anoxia, including (i) the poor sensitivity of the \u03b4\u00b2\u00b3\u2078U proxy when fractional anoxia is high, and (ii) the inherent bias in generating illustrative forward model outputs in stratigraphic sections with expected anoxic intervals. We thus explore inverse modeling approaches to constrain the most likely history of seafloor anoxia for a given \u03b4\u00b2\u00b3\u2078U dataset, and ultimately develop a framework for doing so using Bayesian inference via Markov Chain Monte Carlo simulation. We show that this approach can recover simulated trends, and further reconstruct marine anoxia for eight published \u03b4\u00b2\u00b3\u2078U datasets. We find that some previous interpretations of anoxic seafloor extent were inaccurate, either because steady state was improperly assumed, or because the illustrative forward models used were poor fits to the data. In order to overcome these issues in future work with the \u03b4\u00b2\u00b3\u2078U redox proxy, we have made this model publicly available, and also offer suggestions for the judicious use of forward models. By building on this framework, the future quantification of marine anoxia during transient environmental perturbations can be performed consistently, thereby facilitating robust comparison of anoxic extent between events.", "date": "2022-01-01", "date_type": "published", "publication": "Earth and Planetary Science Letters", "volume": "577", "publisher": "Elsevier", "pagerange": "Art. No. 117240", "id_number": "CaltechAUTHORS:20211110-225053786", "issn": "0012-821X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211110-225053786", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Agouron Institute" }, { "agency": "NSF", "grant_number": "EAR-1824002" }, { "agency": "NSF", "grant_number": "MGG-2054892" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.epsl.2021.117240", "primary_object": { "basename": "1-s2.0-S0012821X21004969-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/4s279-h0c90/files/1-s2.0-S0012821X21004969-mmc1.pdf" }, "pub_year": "2022", "author_list": "Kipp, Michael A. and Tissot, Fran\u00e7ois L. H." }, { "id": "https://authors.library.caltech.edu/records/nn17y-29k34", "eprint_id": 112929, "eprint_status": "archive", "datestamp": "2023-08-22 13:19:17", "lastmod": "2025-11-21 02:28:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Quiroz-Juan", "name": { "family": "Quiroz", "given": "Juan" }, "orcid": "0000-0001-8037-3779" }, { "id": "Wallack-Nicole-L", "name": { "family": "Wallack", "given": "Nicole L." }, "orcid": "0000-0003-0354-0187" }, { "id": "Ren-Bin", "name": { "family": "Ren", "given": "Bin" }, "orcid": "0000-0003-1698-9696" }, { "id": "Dong-Ruobing", "name": { "family": "Dong", "given": "Ruobing" }, "orcid": "0000-0001-9290-7846" }, { "id": "Xuan-Jerry-W", "name": { "family": "Xuan", "given": "Jerry W." }, "orcid": "0000-0002-6618-1137" }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "id": "Millar-Blanchaer-Maxwell-A", "name": { "family": "Millar-Blanchaer", "given": "Maxwell A." }, "orcid": "0000-0001-6205-9233" }, { "id": "Ruane-Garreth-J", "name": { "family": "Ruane", "given": "Garreth" }, "orcid": "0000-0003-4769-1665" } ] }, "title": "Improving Planet Detection with Disk Modeling: Keck/NIRC2 Imaging of the HD 34282 Single-armed Protoplanetary Disk", "ispublished": "pub", "full_text_status": "public", "keywords": "Protoplanetary disks; Coronagraphic imaging; Planetary system formation; Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 October 4; revised 2021 November 23; accepted 2021 November 24; published 2022 January 4. \n\nWe thank the anonymous referee for comments that improved this Letter. This research is partially supported by NASA ROSES XRP award 80NSSC19K0294. We thank Jean-Baptiste Ruffio, Jason Wang, Christian Ginski, and Myriam Benisty for discussions on calculating contrast curves. R.D. acknowledges financial support provided by the Natural Sciences and Engineering Research Council of Canada through a Discovery Grant as well as the Alfred P. Sloan Foundation through a Sloan Research Fellowship. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain. Part of the computations presented here were conducted in the Resnick High Performance Computing Center, a facility supported by the Resnick Sustainability Institute at the California Institute of Technology. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO program 096.C-0248(A). This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This research has made use of the SVO Filter Profile Service (http://svo2.cab.inta-csic.es/theory/fps/) supported from the Spanish MINECO through grant AYA2017-84089. \n\nFacilities: Keck II (NIRC2) - , VLT:Melipal (SPHERE). \n\nSoftware: DebrisDiskFM (Ren et al. 2019), emcee (Foreman-Mackey et al. 2013), IRDAP (van Holstein et al. 2020), VIP (Gomez Gonzalez et al. 2017).\n\n

Published - Quiroz_2022_ApJL_924_L4.pdf

Accepted Version - 2111.12708.pdf

", "abstract": "Formed in protoplanetary disks around young stars, giant planets can leave observational features such as spirals and gaps in their natal disks through planet\u2013disk interactions. Although such features can indicate the existence of giant planets, protoplanetary disk signals can overwhelm the innate luminosity of planets. Therefore, in order to image planets that are embedded in disks, it is necessary to remove the contamination from the disks to reveal the planets possibly hiding within their natal environments. We observe and directly model the detected disk in the Keck/NIRC2 vortex coronagraph L\u2032-band observations of the single-armed protoplanetary disk around HD 34282. Despite a nondetection of companions for HD 34282, this direct disk modeling improves planet detection sensitivity by up to a factor of 2 in flux ratio and \u223c10 M_(Jupiter) in mass. This suggests that performing disk modeling can improve directly imaged planet detection limits in systems with visible scattered light disks, and can help to better constrain the occurrence rates of self-luminous planets in these systems.", "date": "2022-01-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "924", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. L4", "id_number": "CaltechAUTHORS:20220114-265889000", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220114-265889000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC19K0294" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "W. M. Keck Foundation" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)", "grant_number": "AYA2017-84089" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3847/2041-8213/ac3e62", "primary_object": { "basename": "2111.12708.pdf", "url": "https://authors.library.caltech.edu/records/nn17y-29k34/files/2111.12708.pdf" }, "related_objects": [ { "basename": "Quiroz_2022_ApJL_924_L4.pdf", "url": "https://authors.library.caltech.edu/records/nn17y-29k34/files/Quiroz_2022_ApJL_924_L4.pdf" } ], "pub_year": "2022", "author_list": "Quiroz, Juan; Wallack, Nicole L.; et al." }, { "id": "https://authors.library.caltech.edu/records/dr4s9-zvp37", "eprint_id": 112554, "eprint_status": "archive", "datestamp": "2023-08-22 12:56:44", "lastmod": "2023-10-23 22:36:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Versaw-Brooke-A", "name": { "family": "Versaw", "given": "Brooke A." }, "orcid": "0000-0002-6200-7203" }, { "id": "Zeng-Tian", "name": { "family": "Zeng", "given": "Tian" }, "orcid": "0000-0001-5957-3442" }, { "id": "Hu-Xiaoran", "name": { "family": "Hu", "given": "Xiaoran" }, "orcid": "0000-0001-7598-4516" }, { "id": "Robb-M-J", "name": { "family": "Robb", "given": "Maxwell J." }, "orcid": "0000-0002-0528-9857" } ] }, "title": "Harnessing the Power of Force: Development of Mechanophores for Molecular Release", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Drug release, Mechanochemistry, Small molecules, Reactivity, Polymers; Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: November 10, 2021; Published: December 18, 2021. \n\nThe authors gratefully acknowledge financial support from Caltech, the Arnold and Mabel Beckman Foundation through a Beckman Young Investigator Award, and the Donors of the American Chemical Society Petroleum Research Fund through a Doctoral New Investigator Award (Grant 61638-DNI7). B.A.V. was supported by a NSF Graduate Research Fellowship (DGE-1745301). This work was supported in part by Resnick Sustainability Institute. \n\nThe authors declare no competing financial interest.", "abstract": "Polymers that release small molecules in response to mechanical force are promising materials for a variety of applications ranging from sensing and catalysis to targeted drug delivery. Within the rapidly growing field of polymer mechanochemistry, stress-sensitive molecules known as mechanophores are particularly attractive for enabling the release of covalently bound payloads with excellent selectivity and control. Here, we review recent progress in the development of mechanophore-based molecular release platforms and provide an optimistic, yet critical perspective on the fundamental and technological advancements that are still required for this promising research area to achieve significant impact.", "date": "2021-12-29", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "51", "publisher": "American Chemical Society", "pagerange": "21461-21473", "id_number": "CaltechAUTHORS:20211220-590742000", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211220-590742000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "American Chemical Society Petroleum Research Fund", "grant_number": "61638-DNI7" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.1c11868", "pub_year": "2021", "author_list": "Versaw, Brooke A.; Zeng, Tian; et al." }, { "id": "https://authors.library.caltech.edu/records/9879e-fq839", "eprint_id": 112921, "eprint_status": "archive", "datestamp": "2023-08-22 12:54:22", "lastmod": "2023-10-23 22:51:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jongaramrungruang-Siraput", "name": { "family": "Jongaramrungruang", "given": "Siraput" }, "orcid": "0000-0002-2477-2043" }, { "id": "Matheou-Georgios", "name": { "family": "Matheou", "given": "Georgios" }, "orcid": "0000-0003-4024-4571" }, { "id": "Thorpe-Andrew-K", "name": { "family": "Thorpe", "given": "Andrew K." }, "orcid": "0000-0001-7968-5433" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Remote sensing of methane plumes: instrument tradeoff analysis for detecting and quantifying local sources at global scale", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "\u00a9 Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 12 Jul 2021 \u2013 Discussion started: 20 Jul 2021 \u2013 Revised: 18 Oct 2021 \u2013 Accepted: 20 Oct 2021 \u2013 Published: 22 Dec 2021. \n\nThis work is part of Siraput Jongaramrungruang's NASA Earth and Space Science Fellowship (NESSF; grant no. 80NSSC18K1350). We acknowledge the Resnick Sustainability Institute at Caltech, for their kind support with computing resources. We deeply thank Rupesh Jeyaram, for his kind support with a radiative transfer open-source software (https://github.com/RadiativeTransfer, last access: 20 July 2021) and his help with making our computations run faster. \n\nThis research has been supported by the Earth Sciences Division (grant no. 80NSSC18K1350). \n\nAuthor contributions. SJ and CF conceptualized and designed the research objectives. SJ performed the analysis and wrote the paper. GM ran the LES model and provided output. CF provided guidance on the overall design and support on scientific approaches and experimental setups. AKT and ZCZ provided feedback and suggestions on the figures and text. All co-authors contributed to the writing of this paper. \n\nData availability. AVIRIS-NG data are publicly available via the AVIRIS-NG data portal by JPL via https://avirisng.jpl.nasa.gov/dataportal/ (JPL, 2021). \n\nAuthor contributions. SJ and CF conceptualized and designed the research objectives. SJ performed the analysis and wrote the paper. GM ran the LES model and provided output. CF provided guidance on the overall design and support on scientific approaches and experimental setups. AKT and ZCZ provided feedback and suggestions on the figures and text. All co-authors contributed to the writing of this paper. \n\nThe contact author has declared that neither they nor their co-authors have any competing interests. \n\nReview statement. This paper was edited by Gerrit Kuhlmann and reviewed by two anonymous referees.\n\n

Published - amt-14-7999-2021.pdf

", "abstract": "Methane (CH\u2084) is the second most important anthropogenic greenhouse gas with a significant impact on radiative forcing, tropospheric air quality, and stratospheric water vapor. Remote sensing observations enable the detection and quantification of local methane emissions across large geographical areas, which is a critical step for understanding local flux distributions and subsequently prioritizing mitigation strategies. Obtaining methane column concentration measurements with low noise and minimal surface interference has direct consequences for accurately determining the location and emission rates of methane sources. The quality of retrieved column enhancements depends on the choices of the instrument and retrieval parameters. Here, we studied the changes in precision error and bias as a result of different spectral resolutions, instrument optical performance, and detector exposure times by using a realistic instrument noise model. In addition, we formally analyzed the impact of spectrally complex surface albedo features on retrievals using the iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS) algorithm. We built an end-to-end modeling framework that can simulate observed radiances from reflected solar irradiance through a simulated CH\u2084 plume over several natural and artificial surfaces. Our analysis shows that complex surface features can alias into retrieved methane abundances, explaining the existence of retrieval biases in current airborne methane observations. The impact can be mitigated with higher spectral resolution and a larger polynomial degree to approximate surface albedo variations. Using a spectral resolution of 1.5\u2009nm, an exposure time of 20\u2009ms, and a polynomial degree of 25, a retrieval precision error below 0.007\u2009mole\u2009m\u207b\u00b2 or 1.0\u2009% of total atmospheric CH\u2084 column can be achieved for high albedo cases, while minimizing the bias due to surface interference such that the noise is uncorrelated among various surfaces. At coarser spectral resolutions, it becomes increasingly harder to separate complex surface albedo features from atmospheric absorption features. Our modeling framework provides the basis for assessing tradeoffs for future remote sensing instruments and algorithmic designs. For instance, we find that improving the spectral resolution beyond 0.2\u2009nm would actually decrease the retrieval precision, as detector readout noise will play an increasing role. Our work contributes towards building an enhanced monitoring system that can measure CH\u2084 concentration fields to determine methane sources accurately and efficiently at scale.", "date": "2021-12-22", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "14", "number": "12", "publisher": "European Geosciences Union", "pagerange": "7999-8017", "id_number": "CaltechAUTHORS:20220114-12582000", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220114-12582000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC18K1350" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-14-7999-2021", "primary_object": { "basename": "amt-14-7999-2021.pdf", "url": "https://authors.library.caltech.edu/records/9879e-fq839/files/amt-14-7999-2021.pdf" }, "pub_year": "2021", "author_list": "Jongaramrungruang, Siraput; Matheou, Georgios; et al." }, { "id": "https://authors.library.caltech.edu/records/9cgrj-fhy56", "eprint_id": 111980, "eprint_status": "archive", "datestamp": "2023-08-22 12:53:25", "lastmod": "2023-10-23 20:50:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liberman-Martin-Allegra-L", "name": { "family": "Liberman-Martin", "given": "Allegra L." }, "orcid": "0000-0002-8447-905X" }, { "id": "Chang-Alice-B", "name": { "family": "Chang", "given": "Alice B." }, "orcid": "0000-0001-5036-2681" }, { "id": "Chu-Crystal-K", "name": { "family": "Chu", "given": "Crystal K." }, "orcid": "0000-0002-7783-2564" }, { "id": "Siddique-Radwanul-H", "name": { "family": "Siddique", "given": "Radwanul H." }, "orcid": "0000-0001-7494-5857" }, { "id": "Lee-Byeongdu", "name": { "family": "Lee", "given": "Byeongdu" }, "orcid": "0000-0003-2514-8805" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Processing Effects on the Self-Assembly of Brush Block Polymer Photonic Crystals", "ispublished": "pub", "full_text_status": "public", "keywords": "Self organization, X-ray scattering, Order, Annealing (metallurgy), Polymers; Materials Chemistry; Inorganic Chemistry; Polymers and Plastics; Organic Chemistry", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: September 9, 2021; Accepted: November 4, 2021; Published: November 11, 2021.\n\nThis work was supported by the Department of Energy under Award Number DE-AR0000683 (ARPA-E Program) and by the National Science Foundation under Award Number CHE-1502616. A.L.L.-M. thanks the Resnick Sustainability Institute at Caltech for fellowship support and Chapman University for funding. A.B.C. thanks the U.S. Department of Defense for support through the NDSEG Fellowship. Henry Hallam is thanked for assistance measuring the force applied by binder clips. This research used resources of the Advanced Photon Source, a U.S. Department of Energy Office of Science User Facility operated by Argonne National Laboratory under Contract DE-AC02-06CH11357. \n\nAuthor Contributions: A.L.L.-M. and A.B.C. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - mz1c00579_si_001.pdf

Supplemental Material - mz1c00579_si_002.mp4

", "abstract": "The self-assembly of poly(dimethylsiloxane)-b-poly(trimethylene carbonate) (PDMS-b-PTMC) bottlebrush block polymers was investigated under different processing conditions. Small-angle X-ray scattering (SAXS) and UV/Visible spectroscopy provided insight into the self-assembly and structure in response to heating and applied pressure. In the absence of applied pressure (i.e., before annealing), the PDMS-b-PTMC bottlebrush block polymers are white solids and adopt small, randomly oriented lamellar grains. Heating the materials to 140 \u00b0C in the absence of applied pressure appears to \"lock in\" the isotropic, short-range-ordered state, preventing the formation of the long-range-ordered lamellar structure responsible for photonic properties. Applying modest anisotropic pressure (3 psi) between parallel plates at ambient temperature orients the short-range lamellar grains; however, applied pressure alone does not produce long-range order. Only when the bottlebrush block polymers were heated (>100 \u00b0C) under modest pressure (3 psi) were long-range-ordered photonic crystals formed. Analysis of the SAXS data motivated analogies to liquid crystals and revealed the potential self-assembly pathway. These results provide insight into the structure and self-assembly of bottlebrush block polymers with low glass transition temperature side chains in response to different processing conditions.", "date": "2021-12-21", "date_type": "published", "publication": "ACS Macro Letters", "volume": "10", "number": "12", "publisher": "American Chemical Society", "pagerange": "1480-1486", "id_number": "CaltechAUTHORS:20211122-191358476", "issn": "2161-1653", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211122-191358476", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "ARPA-E", "grant_number": "DE-AR0000683" }, { "agency": "NSF", "grant_number": "CHE-1502616" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Chapman University" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsmacrolett.1c00579", "primary_object": { "basename": "mz1c00579_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9cgrj-fhy56/files/mz1c00579_si_001.pdf" }, "related_objects": [ { "basename": "mz1c00579_si_002.mp4", "url": "https://authors.library.caltech.edu/records/9cgrj-fhy56/files/mz1c00579_si_002.mp4" } ], "pub_year": "2021", "author_list": "Liberman-Martin, Allegra L.; Chang, Alice B.; et al." }, { "id": "https://authors.library.caltech.edu/records/wqeg3-zsp42", "eprint_id": 109774, "eprint_status": "archive", "datestamp": "2023-08-22 12:43:33", "lastmod": "2023-12-22 23:33:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oberhofer-Georg", "name": { "family": "Oberhofer", "given": "Georg" }, "orcid": "0000-0003-0930-1996" }, { "id": "Ivy-Tobin", "name": { "family": "Ivy", "given": "Tobin" }, "orcid": "0000-0002-9116-3854" }, { "id": "Hay-B-A", "name": { "family": "Hay", "given": "Bruce A." }, "orcid": "0000-0002-5486-0482" } ] }, "title": "Gene drive that results in addiction to a temperature-sensitive version of an essential gene triggers population collapse in Drosophila", "ispublished": "pub", "full_text_status": "public", "keywords": "gene drive; population suppression; selfish genetic element; Drosophila", "note": "\u00a9 2021 National Academy of Sciences. Published under the PNAS license. \n\nEdited by Dana Carroll, The University of Utah, Salt Lake City, UT, and approved October 14, 2021 (received for review April 21, 2021). \n\nStocks obtained from the Bloomington Drosophila Stock Center (NIH P40OD018537) were used in this study. This work was carried out with support to B.A.H. from the US Department of Agriculture, National Institute of Food and Agriculture (NIFA) specialty crop initiative under US Department of Agriculture NIFA Award No. 2012-51181-20086 and the California Institute of Technology (Caltech) Resnick Sustainability Institute. G.O. was supported by a Baxter Foundation Endowed Senior Postdoctoral Fellowship and the Caltech Resnick Sustainability Institute. T.I. was supported by NIH Training Grant No. 5T32GM007616-39. \n\nData Availability: A ll study data are included in the article and/or supporting information. \n\nAuthor contributions: G.O. and B.A.H. designed research; G.O., T.I., and B.A.H. performed research; G.O., T.I., and B.A.H. analyzed data; and G.O. and B.A.H. wrote the paper. \n\nThis paper results from the NAS Colloquium of the National Academy of Sciences, \"Life 2.0: The Promise and Challenge of a CRISPR Path to a Sustainable Planet,\" held December 10\u201311, 2019, at the Arnold and Mabel Beckman Center of the National Academies of Sciences and Engineering in Irvine, CA. NAS colloquia began in 1991 and have been published in PNAS since 1995. The complete program and video recordings of presentations are available on the NAS website at http://www.nasonline.org/CRISPR. The collection of colloquium papers in PNAS can be found at https://www.pnas.org/cc/the-promise-and-challenge-of-a-crispr-path. \n\nCompeting interest statement: The authors have filed patent applications on ClvR and related technologies (US Application No. 15/970,728 and No. 16/673,823; provisional patent No. CIT-8511-P). \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2107413118/-/DCSupplemental.\n\n

Published - e2107413118.full.pdf

Submitted - 2021.07.03.451005v1.full.pdf

Supplemental Material - pnas.2107413118.sapp.pdf

Supplemental Material - pnas.2107413118.sd01.xlsx

", "abstract": "One strategy for population suppression seeks to use gene drive to spread genes that confer conditional lethality or sterility, providing a way of combining population modification with suppression. Stimuli of potential interest could be introduced by humans, such as an otherwise benign virus or chemical, or occur naturally on a seasonal basis, such as a change in temperature. Cleave and Rescue (ClvR) selfish genetic elements use Cas9 and guide RNAs (gRNAs) to disrupt endogenous versions of an essential gene while also including a Rescue version of the essential gene resistant to disruption. ClvR spreads by creating loss-of-function alleles of the essential gene that select against those lacking it, resulting in populations in which the Rescue provides the only source of essential gene function. As a consequence, if function of the Rescue, a kind of Trojan horse now omnipresent in a population, is condition dependent, so too will be the survival of that population. To test this idea, we created a ClvR in Drosophila in which Rescue activity of an essential gene, dribble, requires splicing of a temperature-sensitive intein (TS-ClvR^(dbe)). This element spreads to transgene fixation at 23\u2009\u00b0C, but when populations now dependent on Ts-ClvR^(dbe) are shifted to 29\u2009\u00b0C, death and sterility result in a rapid population crash. These results show that conditional population elimination can be achieved. A similar logic, in which Rescue activity is conditional, could also be used in homing-based drive and to bring about suppression and/or killing of specific individuals in response to other stimuli.", "date": "2021-12-07", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "118", "number": "49", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2107413118", "id_number": "CaltechAUTHORS:20210712-144929811", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210712-144929811", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "P40OD018537" }, { "agency": "U.S. Department of Agriculture", "grant_number": "2012-51181-20086" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Baxter Foundation" }, { "agency": "NIH Predoctoral Fellowship", "grant_number": "5T32GM007616-39" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1073/pnas.2107413118", "pmcid": "PMC8670509", "primary_object": { "basename": "2021.07.03.451005v1.full.pdf", "url": "https://authors.library.caltech.edu/records/wqeg3-zsp42/files/2021.07.03.451005v1.full.pdf" }, "related_objects": [ { "basename": "e2107413118.full.pdf", "url": "https://authors.library.caltech.edu/records/wqeg3-zsp42/files/e2107413118.full.pdf" }, { "basename": "pnas.2107413118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/wqeg3-zsp42/files/pnas.2107413118.sapp.pdf" }, { "basename": "pnas.2107413118.sd01.xlsx", "url": "https://authors.library.caltech.edu/records/wqeg3-zsp42/files/pnas.2107413118.sd01.xlsx" } ], "pub_year": "2021", "author_list": "Oberhofer, Georg; Ivy, Tobin; et al." }, { "id": "https://authors.library.caltech.edu/records/0bgxb-bzt64", "eprint_id": 112195, "eprint_status": "archive", "datestamp": "2023-08-22 12:43:47", "lastmod": "2023-10-23 17:47:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Le-Linh-N-V", "name": { "family": "Le", "given": "Linh N. V." }, "orcid": "0000-0003-1451-2675" }, { "id": "Bailey-Gwendolyn-A", "name": { "family": "Bailey", "given": "Gwendolyn A." }, "orcid": "0000-0002-6636-4128" }, { "id": "Scott-Anna-G", "name": { "family": "Scott", "given": "Anna G." } }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Partial synthetic models of FeMoco with sulfide and carbyne ligands: Effect of interstitial atom in nitrogenase active site", "ispublished": "pub", "full_text_status": "public", "keywords": "FeMoco model; nitrogenase; carbide clusters; reduction potential; iron-sulfur clusters; Multidisciplinary", "note": "\u00a9 2021 National Academy of Sciences. Published under the PNAS license. \n\nEdited by Marcetta Y. Darensbourg, Texas A&M University, College Station, TX, and approved October 26, 2021 (received for review May 20, 2021). \n\nWe are grateful to the NIH (R01-GM102687B to T.A.), Natural Sciences and Engineering Research Council of Canada (G.A.B.), the Resnick Sustainability Institute at Caltech (G.A.B.), and the NSF (Graduate Research Fellowships Program to A.G.S.) for funding. We thank the Beckman Institute and the Dow Next Generation Grant for instrumentation support. Michael Takase, Lawrence Henling, and Manar Shoshani are thanked for assistance with crystallography. \n\nData Availability: Atomic coordinates and structure factors data have been deposited in the Cambridge Structural Database (CSD) of the Cambridge Crystallographic Data Centre (https://www.ccdc.cam.ac.uk/structures/). CSD reference numbers are as follows: 2084246 (1-Mo), 2081620 (2-W), 2084269 (2-Mo), 2081619 (3), 2081616 (4-W), 2084247 (4-Mo), 2081621 (5), 2081617 (6), 2081622 (7), and 2084054 (8). All other study data are included in the article and/or SI Appendix. \n\nAuthor contributions: L.N.V.L., G.A.B., A.G.S., and T.A. designed research; L.N.V.L., G.A.B., and A.G.S. performed research; L.N.V.L., G.A.B., A.G.S., and T.A. analyzed data; L.N.V.L., G.A.B., A.G.S., and T.A. wrote the paper; and T.A. mentored researchers. \n\nThe authors declare no competing interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2109241118/-/DCSupplemental.\n\n

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", "abstract": "Nitrogen-fixing organisms perform dinitrogen reduction to ammonia at an Fe-M (M = Mo, Fe, or V) cofactor (FeMco) of nitrogenase. FeMco displays eight metal centers bridged by sulfides and a carbide having the MFe\u2087S\u2088C cluster composition. The role of the carbide ligand, a unique motif in protein active sites, remains poorly understood. Toward addressing how the carbon bridge affects the physical and chemical properties of the cluster, we isolated synthetic models of subsite MFe\u2083S\u2083C displaying sulfides and a chelating carbyne ligand. We developed synthetic protocols for structurally related clusters, [Tp*M'Fe\u2083S\u2083X]^(n\u2212), where M' = Mo or W, the bridging ligand X = CR, N, NR, S, and Tp* = Tris(3,5-dimethyl-1-pyrazolyl)hydroborate, to study the effects of the identity of the heterometal and the bridging X group on structure and electrochemistry. While the nature of M' results in minor changes, the chelating, \u03bc\u2083-bridging carbyne has a large impact on reduction potentials, being up to 1 V more reducing compared to nonchelating N and S analogs.", "date": "2021-12-07", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "118", "number": "49", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2109241118", "id_number": "CaltechAUTHORS:20211203-175255320", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211203-175255320", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01-GM102687B" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.2109241118", "pmcid": "PMC8670491", "primary_object": { "basename": "e2109241118.full.pdf", "url": "https://authors.library.caltech.edu/records/0bgxb-bzt64/files/e2109241118.full.pdf" }, "related_objects": [ { "basename": "pnas.2109241118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/0bgxb-bzt64/files/pnas.2109241118.sapp.pdf" } ], "pub_year": "2021", "author_list": "Le, Linh N. V.; Bailey, Gwendolyn A.; et al." }, { "id": "https://authors.library.caltech.edu/records/9qf90-b8928", "eprint_id": 108797, "eprint_status": "archive", "datestamp": "2023-08-22 12:26:21", "lastmod": "2023-12-22 23:33:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Zhen", "name": { "family": "Liu", "given": "Zhen" }, "orcid": "0000-0002-1119-0693" }, { "id": "Calv\u00f3-Tusell-Carla", "name": { "family": "Calv\u00f3-Tusell", "given": "Carla" }, "orcid": "0000-0003-2681-8460" }, { "id": "Zhou-Andrew-Z", "name": { "family": "Zhou", "given": "Andrew Z." }, "orcid": "0000-0002-1763-7353" }, { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Garcia-Borr\u00e0s-Marc", "name": { "family": "Garcia-Borr\u00e0s", "given": "Marc" }, "orcid": "0000-0001-9458-1114" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Dual-function enzyme catalysis for enantioselective carbon\u2013nitrogen bond formation", "ispublished": "pub", "full_text_status": "public", "keywords": "Biocatalysis; Computational chemistry", "note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2021. \n\nReceived 14 April 2021; Accepted 23 August 2021; Published 18 October 2021. \n\nThis work was supported by the National Science Foundation Division of Molecular and Cellular Biosciences (grant 2016137 to F.H.A.), the US Army Research Office Institute for Collaborative Biotechnologies (cooperative agreement W911NF-19-2-0026 to F.H.A.), the Spanish Ministry of Science and Innovation MICINN (grant PID2019-111300GA-I00 to M.G.-B.) and the Generalitat de Catalunya AGAUR Beatriu de Pin\u00f3s H2020 MSCA-Cofund (2018-BP-00204 project to M.G.-B.). K.C. thanks the Resnick Sustainability Institute at Caltech for fellowship support. The computer resources at MinoTauro and the Barcelona Supercomputing Center BSC-RES are acknowledged (RES-QSB-2020-2-0016). We thank D. C. Miller, S. Brinkmann-Chen, R. Lal and T. Zeng for helpful discussions and comments on the manuscript. We further thank M. Shahgholi for high-resolution mass spectrometry analysis and M. K. Takase for X-ray crystallographic analysis. \n\nData availability: All data necessary to support the paper's conclusions are available in the main text and the Supplementary Information. X-ray crystal structures of 3e (CCDC 2065484) and 3l (CCDC 2065489) are available free of charge from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif. Plasmids encoding the enzymes reported in this study are available for research purposes from F.H.A. under a material transfer agreement with the California Institute of Technology. Source data are provided with this paper. \n\nAuthor Contributions: Z.L. and K.C. conceived and designed the overall project with F.H.A. providing guidance. Z.L. and A.Z.Z. designed and performed the initial screening of haem proteins and the substrate scope study. C.C.-T. and M.G.-B. carried out the computational studies. Z.L., K.C., M.G.-B. and F.H.A. wrote the manuscript with the input of all authors. \n\nCompeting interests: K.C., Z.L. and A.Z.Z. are inventors on a US Patent Application (invention title, Diverse Carbene Transferase Enzyme Catalysts Derived from a P450 Enzyme; application no., 17/200,394) filed by the California Institute of Technology, which covers lactone-carbene N\u2013H insertion with engineered P450 enzymes. The patent was filed on 12 March 2021. The remaining authors declare no competing interests. \n\nPeer review information: Nature Chemistry thanks Sabine Flitsch, Sason Shaik and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\n

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", "abstract": "Chiral amines can be made by insertion of a carbene into an N\u2013H bond using two-catalyst systems that combine a transition metal-based carbene-transfer catalyst and a chiral proton-transfer catalyst to enforce stereocontrol. Haem proteins can effect carbene N\u2013H insertion, but asymmetric protonation in an active site replete with proton sources is challenging. Here we describe engineered cytochrome P450 enzymes that catalyse carbene N\u2013H insertion to prepare biologically relevant \u03b1-amino lactones with high activity and enantioselectivity (up to 32,100 total turnovers, >99% yield and 98%\u2009e.e.). These enzymes serve as dual-function catalysts, inducing carbene transfer and promoting the subsequent proton transfer with excellent stereoselectivity in a single active site. Computational studies uncover the detailed mechanism of this new-to-nature enzymatic reaction and explain how active-site residues accelerate this transformation and provide stereocontrol.", "date": "2021-12", "date_type": "published", "publication": "Nature Chemistry", "volume": "13", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "1166-1172", "id_number": "CaltechAUTHORS:20210421-171106293", "issn": "1755-4330", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210421-171106293", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-2016137" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-2-0026" }, { "agency": "Ministerio de Ciencia e Innovaci\u00f3n (MCINN)", "grant_number": "PID2019-111300GA-I00" }, { "agency": "Generalitat de Catalunya", "grant_number": "2018-BP-00204" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Barcelona Supercomputing Center (BSC)", "grant_number": "RES-QSB-2020-2-0016" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1038/s41557-021-00794-z", "primary_object": { "basename": "41557_2021_794_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/41557_2021_794_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41557_2021_794_MOESM2_ESM.cif", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/41557_2021_794_MOESM2_ESM.cif" }, { "basename": "41557_2021_794_MOESM3_ESM.cif", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/41557_2021_794_MOESM3_ESM.cif" }, { "basename": "41557_2021_794_MOESM4_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/41557_2021_794_MOESM4_ESM.xlsx" }, { "basename": "41557_2021_794_MOESM5_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/41557_2021_794_MOESM5_ESM.xlsx" }, { "basename": "41557_2021_794_MOESM6_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/41557_2021_794_MOESM6_ESM.xlsx" }, { "basename": "Manuscript-carbene_NH_insertion-0419.pdf", "url": "https://authors.library.caltech.edu/records/9qf90-b8928/files/Manuscript-carbene_NH_insertion-0419.pdf" } ], "pub_year": "2021", "author_list": "Liu, Zhen; Calv\u00f3-Tusell, Carla; et al." }, { "id": "https://authors.library.caltech.edu/records/jpqx4-32a63", "eprint_status": "archive", "datestamp": "2026-02-24 16:29:48", "lastmod": "2026-02-24 16:29:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singer-Clare-E", "name": { "family": "Singer", "given": "Clare E." }, "orcid": "0000-0002-1708-0997" }, { "id": "Lopez-Gomez-Ignacio", "name": { "family": "Lopez-Gomez", "given": "Ignacio" }, "orcid": "0000-0002-7255-5895" }, { "id": "Zhang-Xiyue", "name": { "family": "Zhang", "given": "Xiyue" }, "orcid": "0000-0002-6031-7830" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "Top-of-Atmosphere Albedo Bias from Neglecting Three-Dimensional Cloud Radiative Effects", "ispublished": "pub", "full_text_status": "public", "keywords": "Cloud radiative effects; Model errors; Radiative transfer; Shortwave radiation", "note": "

© 2021 American Meteorological Society.

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C.E.S. acknowledges support from NSF Graduate Research Fellowship under Grant DGE-1745301. I.L. is supported by a fellowship from the Resnick Sustainability Institute at Caltech. This research was additionally supported by the generosity of Eric and Wendy Schmidt by recommendation of the Schmidt Futures program. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. We thank three anonymous reviewers for helpful comments on an earlier version of this paper.

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All code or data used in this paper are freely available online. The LES were run using the PyCLES code (https://climate-dynamics.org/software/#pycles). The radiative transfer computations were done using the libRadtran code (http://www.libradtran.org). Post-processed LES 3D fields used as input files for libRadtran computations are available in Singer et al. (2020). The ISCCP data were downloaded from https://climserv.ipsl.polytechnique.fr/gewexca/ and the GEWEX albedo measurements were downloaded from https://eosweb.larc.nasa.gov.

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", "abstract": "
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Clouds cover on average nearly 70% of Earth’s surface and regulate the global albedo. The magnitude of the shortwave reflection by clouds depends on their location, optical properties, and three-dimensional (3D) structure. Due to computational limitations, Earth system models are unable to perform 3D radiative transfer calculations. Instead they make assumptions, including the independent column approximation (ICA), that neglect effects of 3D cloud morphology on albedo. We show how the resulting radiative flux bias (ICA-3D) depends on cloud morphology and solar zenith angle. We use high-resolution (20–100-m horizontal resolution) large-eddy simulations to produce realistic 3D cloud fields covering three dominant regimes of low-latitude clouds: shallow cumulus, marine stratocumulus, and deep convective cumulonimbus. A Monte Carlo code is used to run 3D and ICA broadband radiative transfer calculations; we calculate the top-of-atmosphere (TOA) reflected flux and surface irradiance biases as functions of solar zenith angle for these three cloud regimes. Finally, we use satellite observations of cloud water path (CWP) climatology, and the robust correlation between CWP and TOA flux bias in our LES sample, to roughly estimate the impact of neglecting 3D cloud radiative effects on a global scale. We find that the flux bias is largest at small zenith angles and for deeper clouds, while the albedo bias is most prominent for large zenith angles. In the tropics, the annual-mean shortwave radiative flux bias is estimated to be 3.1 ± 1.6 W m−2, reaching as much as 6.5 W m−2 locally.

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", "date": "2021-12", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "78", "number": "12", "publisher": "American Meteorological Society", "pagerange": "4053-4069", "issn": "0022-4928", "official_url": "https://authors.library.caltech.edu/records/jpqx4-32a63", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-21-0032.1", "primary_object": { "basename": "atsc-JAS-D-21-0032.1.pdf", "url": "https://authors.library.caltech.edu/records/jpqx4-32a63/files/atsc-JAS-D-21-0032.1.pdf" }, "pub_year": "2021", "author_list": "Singer, Clare E.; Lopez-Gomez, Ignacio; et al." }, { "id": "https://authors.library.caltech.edu/records/3wjpr-3j196", "eprint_id": 111867, "eprint_status": "archive", "datestamp": "2023-08-22 11:59:34", "lastmod": "2023-10-23 20:47:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" }, "orcid": "0000-0003-0697-508X" }, { "id": "Yuan-Zhiquan", "name": { "family": "Yuan", "given": "Zhiquan" } }, { "id": "Wu-Lue", "name": { "family": "Wu", "given": "Lue" }, "orcid": "0000-0002-7503-7057" }, { "id": "Suh-Myoung-Gyun", "name": { "family": "Suh", "given": "Myoung-Gyun" }, "orcid": "0000-0002-9527-0585" }, { "id": "Wang-Heming", "name": { "family": "Wang", "given": "Heming" }, "orcid": "0000-0003-3861-0624" }, { "id": "Lin-Qiang", "name": { "family": "Lin", "given": "Qiang" } }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry J." }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Architecture for microcomb-based GHz-mid-infrared dual-comb spectroscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "Frequency combs; Imaging and sensing; Mid-infrared photonics; Solitons", "note": "\u00a9 The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 06 April 2021; Accepted 25 October 2021; Published 12 November 2021. \n\nThe authors thank Scott Diddams at NIST and Lukasz Sterczewski at JPL for helpful discussions. This work is supported by the Defence Threat Reduction Agency-Joint Science and Technology Office for Chemical and Biological Defence (grant No. HD-TRA11810047), the Air Force Office of Scientific Research (FA9550-18-1-0353) and the Kavli Nanoscience Institute. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred. C.B. gratefully acknowledges postdoctoral fellowship support from the Resnick Institute at Caltech. \n\nData availability: The data that supports the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. \n\nCode availability: The code that supports dual-comb signal processing and other findings of this study are available from the corresponding author upon reasonable request. \n\nAuthor Contributions: C.B., Z.Y., Q.L. and K.J.V. conceived the project. C.B. and Z.Y. ran the DCS measurements, and analyzed the results with assistance from H.W. The samples were prepared by L.W. and M-G.S. All authors participated in preparing the manuscript. The project was supervised by K.J.V. \n\nThese authors contributed equally: Chengying Bao and Zhiquan Yuan. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications\u2009thanks the anonymous reviewer(s) for their contribution to the peer review of this work.\n\n

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", "abstract": "Dual-comb spectroscopy (DCS) offers high sensitivity and wide spectral coverage without the need for bulky spectrometers or mechanical moving parts. And DCS in the mid-infrared (mid-IR) is of keen interest because of inherently strong molecular spectroscopic signatures in these bands. We report GHz-resolution mid-IR DCS of methane and ethane that is derived from counter-propagating (CP) soliton microcombs in combination with interleaved difference frequency generation. Because all four combs required to generate the two mid-IR combs rely upon stability derived from a single high-Q microcavity, the system architecture is both simplified and does not require external frequency locking. Methane and ethane spectra are measured over intervals as short as 0.5 ms, a time scale that can be further reduced using a different CP soliton arrangement. Also, tuning of spectral resolution on demand is demonstrated. Although at an early phase of development, the results are a step towards mid-IR gas sensors with chip-based architectures for chemical threat detection, breath analysis, combustion studies, and outdoor observation of trace gases.", "date": "2021-11-12", "date_type": "published", "publication": "Nature Communications", "volume": "12", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 6573", "id_number": "CaltechAUTHORS:20211115-171501194", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211115-171501194", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Threat Reduction Agency (DTRA)", "grant_number": "HD-TRA11810047" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0353" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-021-26958-6", "pmcid": "PMC8589843", "primary_object": { "basename": "s41467-021-26958-6.pdf", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/s41467-021-26958-6.pdf" }, "related_objects": [ { "basename": "41467_2021_26958_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/41467_2021_26958_MOESM1_ESM.pdf" }, { "basename": "41467_2021_26958_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/41467_2021_26958_MOESM2_ESM.pdf" }, { "basename": "41467_2021_26958_MOESM3_ESM.gif", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/41467_2021_26958_MOESM3_ESM.gif" }, { "basename": "41467_2021_26958_MOESM4_ESM.gif", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/41467_2021_26958_MOESM4_ESM.gif" }, { "basename": "41467_2021_26958_MOESM5_ESM.gif", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/41467_2021_26958_MOESM5_ESM.gif" }, { "basename": "41467_2021_26958_MOESM6_ESM.gif", "url": "https://authors.library.caltech.edu/records/3wjpr-3j196/files/41467_2021_26958_MOESM6_ESM.gif" } ], "pub_year": "2021", "author_list": "Bao, Chengying; Yuan, Zhiquan; et al." }, { "id": "https://authors.library.caltech.edu/records/2xpwh-x1m66", "eprint_id": 111916, "eprint_status": "archive", "datestamp": "2023-08-20 05:52:37", "lastmod": "2025-11-18 23:29:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Moreno-Hernandez-Ivan-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Read-Carlos-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Simonoff-Ethan", "name": { "family": "Simonoff", "given": "Ethan" }, "orcid": "0000-0002-2156-8602" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Investigations of the stability of etched or platinized p-InP(100) photocathodes for solar-driven hydrogen evolution in acidic or alkaline aqueous electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Royal Society of Chemistry 2021. \n\nSubmitted 09 Sep 2021; Accepted 23 Sep 2021; First published 30 Sep 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and under award DE-SC0022087 from the Basic Energy Sciences Office of the DOE. Research was in part carried out at the Molecular Materials Resource Center (MMRC) of the Beckman Institute of the California Institute of Technology. W. Yu and C. G. Read acknowledge the Resnick Sustainability Institute (RSI) at Caltech for fellowship support. I. A. Moreno-Hernandez acknowledges a National Science Foundation Graduate Research Fellowship (Grant No. DGE-1144469). Prof. Dr Hans-Joachim Lewerenz, Dr Ke Sun and Dr Chengxiang Xiang are gratefully acknowledged for inspiring discussions. Dr Kimberly M. Papadantonakis is thanked for assistance with manuscript editing. Dr Nathan Dalleska is thanked for assistance with ICP-MS analyses. Ryan Jones is acknowledged for assistance with the design of the compression cell. Sean Byrne and Heng Dong are acknowledged for assistance with experiments. \n\nThere are no conflicts to declare.\n\n

Supplemental Material - d1ee02809j1.pdf

", "abstract": "The stability of p-InP photocathodes performing the hydrogen-evolution reaction (HER) has been evaluated in contact with either 1.0 M H\u2082SO\u2084 (aq) or 1.0 M KOH(aq), with a focus on identifying corrosion mechanisms. Stability for the solar-driven HER was evaluated using p-InP electrodes that were either etched or coated with an electrodeposited Pt catalyst (p-InP/Pt). Variables such as trace O\u2082 were systematically controlled during the measurements. Changes in surface characteristics after exposure to electrochemical conditions as well as electrode dissolution processes were monitored using X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma mass spectrometry (ICP-MS). In either H\u2082SO\u2084 or KOH, etched p-InP photoelectrodes corroded cathodically under illumination, forming metallic In\u2070 at the electrode surface. In contrast, electrodeposition of Pt kinetically stabilized illuminated p-InP photocathodes in both H\u2082SO\u2084 and KOH by inhibiting the cathodic corrosion pathway. Notably, when held at 0 V vs. the reversible hydrogen electrode (RHE) in 1.0 M H\u2082SO\u2084 (aq), p-InP/Pt exhibited a stable current density (J) of \u223c\u221218 mA cm\u207b\u00b2 for >285 h under simulated 1 Sun illumination. The long-term current density vs. potential (J\u2013E) behavior at pH 0 and pH 14 of p-InP/Pt photocathodes correlated with changes in the surface chemistry as well as the dissolution of p-InP. In acidic media, the J\u2013E behavior of p-InP/Pt photocathodes remained nearly constant with time, but the surface of a p-InP/Pt electrodes gradually turned P-rich via a slow and continuous leaching of In ions. In alkaline electrolyte, the surface of p-InP/Pt electrodes was passivated by formation of an InO_x layer that exhibited negligible dissolution but led to a substantial degradation in the J\u2013E characteristics. Consequently, changes in the catalytic kinetics and surface stoichiometry are both important considerations for determining the corrosion chemistry and the long-term operational stability of InP photoelectrodes.", "date": "2021-11-01", "date_type": "published", "publication": "Energy & Environmental Science", "volume": "14", "number": "11", "publisher": "Royal Society of Chemistry", "pagerange": "6007-6020", "id_number": "CaltechAUTHORS:20211117-163656680", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211117-163656680", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d1ee02809j", "primary_object": { "basename": "d1ee02809j1.pdf", "url": "https://authors.library.caltech.edu/records/2xpwh-x1m66/files/d1ee02809j1.pdf" }, "pub_year": "2021", "author_list": "Yu, Weilai; Richter, Matthias H.; et al." }, { "id": "https://authors.library.caltech.edu/records/s94ac-pr864", "eprint_id": 109023, "eprint_status": "archive", "datestamp": "2023-08-20 05:46:49", "lastmod": "2023-10-23 15:38:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Zachary-J", "name": { "family": "Lee", "given": "Zachary J." }, "orcid": "0000-0002-5358-2388" }, { "id": "Sharma-Sunash", "name": { "family": "Sharma", "given": "Sunash" }, "orcid": "0000-0002-8763-5927" }, { "id": "Johansson-Daniel", "name": { "family": "Johansson", "given": "Daniel" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "ACN-Sim: An Open-Source Simulator for Data-Driven Electric Vehicle Charging Research", "ispublished": "pub", "full_text_status": "public", "keywords": "Electric vehicles, computer simulation, charging stations, distributed energy resources, open-source software, cyber-physical systems", "note": "\u00a9 2021 IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/. \n\nManuscript received November 4, 2020; revised March 28, 2021 and July 3, 2021; accepted July 6, 2021. Date of publication August 9, 2021; date of current version October 21, 2021. \n\nThis work was supported in part by the National Science Foundation under the Graduate Research Fellowship Program under Grant 1745301, in part by NSF ECCS under Grant 1932611 and Grant 1619352, in part by NSF CCF under Grant 1637598, and in part by NSF CPS under Grant 1739355. It also received support under the Resnick Sustainability Institute Graduate Fellowship. \n\nThe authors would like to thank the team at PowerFlex, especially Cheng Jin, Ted Lee, and George Lee, as well as Rand Lee, James Anderson, and Jorn Reniers, for providing data, expertise, and ideas to this project.\n\n

Published - ACN-Sim_An_Open-Source_Simulator_for_Data-Driven_Electric_Vehicle_Charging_Research.pdf

Submitted - 2012.02809.pdf

", "abstract": "ACN-Sim is a data-driven, open-source simulation environment designed to accelerate research in the field of smart electric vehicle (EV) charging. It fills the need in this community for a widely available, realistic simulation environment in which researchers can evaluate algorithms and test assumptions. ACN-Sim provides a modular, extensible architecture, which models the complexity of real charging systems, including battery charging behavior and unbalanced three-phase infrastructure. It also integrates with a broader ecosystem of research tools. These include ACN-Data, an open dataset of EV charging sessions, which provides realistic simulation scenarios and ACN-Live, a framework for field-testing charging algorithms. It also integrates with grid simulators like MATPOWER, PandaPower and OpenDSS, and OpenAI Gym for training reinforcement learning agents.", "date": "2021-11", "date_type": "published", "publication": "IEEE Transactions on Smart Grid", "volume": "12", "number": "6", "publisher": "IEEE", "pagerange": "5113-5123", "id_number": "CaltechAUTHORS:20210510-085201964", "issn": "1949-3053", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210510-085201964", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "ECCS-1932611" }, { "agency": "NSF", "grant_number": "ECCS-1619352" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "ECCS-1739355" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TSG.2021.3103156", "primary_object": { "basename": "2012.02809.pdf", "url": "https://authors.library.caltech.edu/records/s94ac-pr864/files/2012.02809.pdf" }, "related_objects": [ { "basename": "ACN-Sim_An_Open-Source_Simulator_for_Data-Driven_Electric_Vehicle_Charging_Research.pdf", "url": "https://authors.library.caltech.edu/records/s94ac-pr864/files/ACN-Sim_An_Open-Source_Simulator_for_Data-Driven_Electric_Vehicle_Charging_Research.pdf" } ], "pub_year": "2021", "author_list": "Lee, Zachary J.; Sharma, Sunash; et al." }, { "id": "https://authors.library.caltech.edu/records/sahhv-ks850", "eprint_id": 109461, "eprint_status": "archive", "datestamp": "2023-08-20 05:43:49", "lastmod": "2023-10-23 15:33:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lai-Yunchieh", "name": { "family": "Lai", "given": "Yunchieh" } }, { "id": "Watkins-Nicholas-B", "name": { "family": "Watkins", "given": "Nicholas B." }, "orcid": "0000-0001-7251-9387" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Heim-Gavin-P", "name": { "family": "Heim", "given": "Gavin P." }, "orcid": "0000-0002-9244-6565" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Wu-Yueshen", "name": { "family": "Wu", "given": "Yueshen" }, "orcid": "0000-0002-3784-0594" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Breaking Scaling Relationships in CO\u2082 Reduction on Copper Alloys with Organic Additives", "ispublished": "pub", "full_text_status": "public", "keywords": "Additives, Alloys, Electrical properties, Catalysts, Selectivity", "note": "\u00a9 2021 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) \n\nReceived: July 16, 2021; Published: October 14, 2021. \n\nThis material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award DE-SC0021266. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). The Resnick Sustainability Institute at Caltech is acknowledged for support of the laboratory facilities in which this research was conducted. \n\nAuthor Contributions: Y.L. and N.B.W. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Published - acscentsci.1c00860.pdf

Submitted - Breaking_Scaling_Relationships_in_CO2_Reduction_on_Copper_Alloys_with_Organic_Additives_v1.pdf

Supplemental Material - oc1c00860_si_001.pdf

", "abstract": "Boundary conditions for catalyst performance in the conversion of common precursors such as N\u2082, O\u2082, H\u2082O, and CO\u2082 are governed by linear free energy and scaling relationships. Knowledge of these limits offers an impetus for designing strategies to alter reaction mechanisms to improve performance. Typically, experimental demonstrations of linear trends and deviations from them are composed of a small number of data points constrained by inherent experimental limitations. Herein, high-throughput experimentation on 14 bulk copper bimetallic alloys allowed for data-driven identification of a scaling relationship between the partial current densities of methane and C\u2082\u208a products. This strict dependence represents an intrinsic limit to the Faradaic efficiency for C\u2013C coupling. We have furthermore demonstrated that coating the electrodes with a molecular film breaks the scaling relationship to promote C\u2082\u208a product formation.", "date": "2021-10-27", "date_type": "published", "publication": "ACS Central Science", "volume": "7", "number": "10", "publisher": "American Chemical Society", "pagerange": "1756-1762", "id_number": "CaltechAUTHORS:20210610-080047277", "issn": "2374-7951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210610-080047277", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1021/acscentsci.1c00860", "pmcid": "PMC8554824", "primary_object": { "basename": "oc1c00860_si_001.pdf", "url": "https://authors.library.caltech.edu/records/sahhv-ks850/files/oc1c00860_si_001.pdf" }, "related_objects": [ { "basename": "acscentsci.1c00860.pdf", "url": "https://authors.library.caltech.edu/records/sahhv-ks850/files/acscentsci.1c00860.pdf" }, { "basename": "Breaking_Scaling_Relationships_in_CO2_Reduction_on_Copper_Alloys_with_Organic_Additives_v1.pdf", "url": "https://authors.library.caltech.edu/records/sahhv-ks850/files/Breaking_Scaling_Relationships_in_CO2_Reduction_on_Copper_Alloys_with_Organic_Additives_v1.pdf" } ], "pub_year": "2021", "author_list": "Lai, Yunchieh; Watkins, Nicholas B.; et al." }, { "id": "https://authors.library.caltech.edu/records/ytnj6-kmk84", "eprint_id": 109111, "eprint_status": "archive", "datestamp": "2023-08-20 05:43:29", "lastmod": "2023-10-23 15:33:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kazmierczak-Nathanael-P", "name": { "family": "Kazmierczak", "given": "Nathanael P." }, "orcid": "0000-0002-7822-6769" }, { "id": "Mirzoyan-Ruben", "name": { "family": "Mirzoyan", "given": "Ruben" }, "orcid": "0000-0002-2334-4012" }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" } ] }, "title": "The Impact of Ligand Field Symmetry on Molecular Qubit Coherence", "ispublished": "pub", "full_text_status": "public", "keywords": "Group theory, Quantum mechanics, Molecular modeling, Excited states, Oscillation", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: May 3, 2021; Published: October 7, 2021. \n\nThe authors thank Dr. Alec Follmer for helpful discussions. N.P.K. acknowledges support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1745301. This paper's computational modeling was supported in part by National Science Foundation MRI-Grant 1726260 based at Calvin University in Grand Rapids, MI, USA. The computations presented here were also conducted in part in the Resnick High Performance Computing Center, a facility supported by Resnick Sustainability Institute at the California Institute of Technology. Financial support from Caltech and the Dow Next Generation Educator Fund is gratefully acknowledged. \n\nThe authors declare no competing financial interest.\n\n

Submitted - T1_MS_chemrxiv.pdf

Supplemental Material - ja1c04605_si_001.pdf

", "abstract": "Developing quantum bits (qubits) exhibiting room temperature electron spin coherence is a key goal of molecular quantum information science. At high temperatures, coherence is often limited by electron spin relaxation, measured by T\u2081. Here we develop a simple and powerful model for predicting relative T\u2081 relaxation times in transition metal complexes from dynamic ligand field principles. By considering the excited state origins of ground state spin-phonon coupling, we derive group theory selection rules governing which vibrational symmetries can induce decoherence. Thermal weighting of the coupling terms produces surprisingly good predictions of experimental T\u2081 trends as a function of temperature and explains previously confounding features in spin\u2013lattice relaxation data. We use this model to evaluate experimental relaxation rates across S = 1/2 transition metal qubit candidates with diverse structures, gaining new insights into the interplay between spin-phonon coupling and molecular symmetry. This methodology elucidates the specific vibrational modes giving rise to decoherence, providing insight into the origin of room temperature coherence in transition metal complexes. We discuss the outlook of symmetry-based modeling and design strategies for understanding molecular coherence.", "date": "2021-10-27", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "42", "publisher": "American Chemical Society", "pagerange": "17305-17315", "id_number": "CaltechAUTHORS:20210513-100749414", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210513-100749414", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "OAC-1726260" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.1c04605", "primary_object": { "basename": "ja1c04605_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ytnj6-kmk84/files/ja1c04605_si_001.pdf" }, "related_objects": [ { "basename": "T1_MS_chemrxiv.pdf", "url": "https://authors.library.caltech.edu/records/ytnj6-kmk84/files/T1_MS_chemrxiv.pdf" } ], "pub_year": "2021", "author_list": "Kazmierczak, Nathanael P.; Mirzoyan, Ruben; et al." }, { "id": "https://authors.library.caltech.edu/records/04vf8-fqh90", "eprint_id": 113700, "eprint_status": "archive", "datestamp": "2023-08-22 11:36:23", "lastmod": "2023-10-23 23:11:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gonz\u00e1lez-Grand\u00edo-Eduardo", "name": { "family": "Gonz\u00e1lez-Grand\u00edo", "given": "Eduardo" }, "orcid": "0000-0002-2059-4542" }, { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" }, { "id": "Ma-Wenhe", "name": { "family": "Ma", "given": "Wenhe" } }, { "id": "Brady-Siobhan-M", "name": { "family": "Brady", "given": "Siobhan" }, "orcid": "0000-0001-9424-8055" }, { "id": "Landry-Markita-P", "name": { "family": "Landry", "given": "Markita P." }, "orcid": "0000-0002-5832-8522" } ] }, "title": "A Ratiometric Dual Color Luciferase Reporter for Fast Characterization of Transcriptional Regulatory Elements in Plants", "ispublished": "pub", "full_text_status": "public", "keywords": "synthetic biology transcriptional regulation reporter assay luciferase plant; Biochemistry, Genetics and Molecular Biology (miscellaneous); Biomedical Engineering; General Medicine", "note": "\u00a9 2021 American Chemical Society. \n\nReceived 18 June 2021. Published online 14 September 2021. Published in issue 15 October 2021. \n\nM.P.L. acknowledges support of a USDA BBT EAGER award (2019-67013-29104) and a USDA NIFA award (2018-67021-27964). G.S.D. is supported by the Resnick Sustainability Institute Postdoctoral Fellowship, and G.S.D. and S.M.B. acknowledge support of a USDA BBT-EAGER award (2019-67013-29012), and partial support by an HHMI Faculty Scholar fellowship. pRedF was a gift from Koen Venken (Addgene #118057). \n\nAuthor Contributions. E.G. and M.P.L. conceived the project and wrote the manuscript. E.G., G.S.D., S.M.B., and M.P.L. designed the experiments. E.G. performed the experiments and data analysis. E.G. and W.M. prepared the plasmids. G.S.D. performed the nitrate experiments. All authors have edited and commented on the manuscript and have given their approval of the final version. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - sb1c00248_si_001.xlsx

Supplemental Material - sb1c00248_si_002.xlsx

", "abstract": "Plant synthetic biology requires precise characterization of genetic elements to construct complex genetic circuits that can improve plant traits or confer them with new characteristics. Transcriptional reporter assays are essential to quantify the effect of gene expression regulator elements. Additionally, transcriptional reporter systems are a key tool in understanding control of gene expression in biology. In this work, we construct and characterize a dual color luciferase ratiometric reporter system that possesses several advantages over currently used reporters. It is ratiometric, thus reducing variability and increasing consistency between experiments; it is fast, as both reporters can be measured at the same time in a single reaction, and it is less expensive to perform than current dual luciferase reporter assays. We have validated our system quantifying the transcriptional capability of a panel of promoters and terminators commonly used in synthetic biology with a broad range of expression magnitudes, and in a biologically relevant system, nitrate response.", "date": "2021-10-15", "date_type": "published", "publication": "ACS Synthetic Biology", "volume": "10", "number": "10", "publisher": "American Chemical Society", "pagerange": "2763-2766", "id_number": "CaltechAUTHORS:20220302-323877000", "issn": "2161-5063", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220302-323877000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Agriculture", "grant_number": "2019-67013-29104" }, { "agency": "Department of Agriculture", "grant_number": "2018-67021-27964" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Agriculture", "grant_number": "2019-67013-29012" }, { "agency": "Howard Hughes Medical Institute (HHMI)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acssynbio.1c00248", "primary_object": { "basename": "sb1c00248_si_001.xlsx", "url": "https://authors.library.caltech.edu/records/04vf8-fqh90/files/sb1c00248_si_001.xlsx" }, "related_objects": [ { "basename": "sb1c00248_si_002.xlsx", "url": "https://authors.library.caltech.edu/records/04vf8-fqh90/files/sb1c00248_si_002.xlsx" } ], "pub_year": "2021", "author_list": "Gonz\u00e1lez-Grand\u00edo, Eduardo; Demirer, Gozde S.; et al." }, { "id": "https://authors.library.caltech.edu/records/95hh3-zeb55", "eprint_id": 110944, "eprint_status": "archive", "datestamp": "2023-08-20 05:14:54", "lastmod": "2025-04-23 01:12:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Fenwick-Aidan-Q", "name": { "family": "Fenwick", "given": "Aidan Q." }, "orcid": "0000-0003-4442-0878" }, { "id": "B\u00f6hme-Annette", "name": { "family": "B\u00f6hme", "given": "Annette" }, "orcid": "0000-0003-1109-3428" }, { "id": "Chen-Hsiang-Yun", "name": { "family": "Chen", "given": "Hsiang-Yun" }, "orcid": "0000-0002-6461-1519" }, { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "Li-Xueqian", "name": { "family": "Li", "given": "Xueqian" }, "orcid": "0000-0002-1197-3743" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Operando Local pH Measurement within Gas Diffusion Electrodes Performing Electrochemical Carbon Dioxide Reduction", "ispublished": "pub", "full_text_status": "public", "keywords": "Redox reactions, Layers, Electrical properties, Electrodes, Electrolytes", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: July 14, 2021; Published: September 17, 2021. \n\nThis work was performed within the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. A.J.W. acknowledges support from the Resnick Sustainability Institute at Caltech for fellowship support and from the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 174530. The authors thank Justin Bui and Alex King at UC Berkeley for their assistance in developing the COMSOL simulations. Any opinions, findings, and conclusions expressed in this material are those of the authors and do not necessarily reflect those of DOE or NSF. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - jp1c06265_si_001.pdf

", "abstract": "The local pH near the surface of a CO\u2082 reduction electrocatalyst strongly impacts catalytic selectivity and activity. Here, confocal fluorescence microscopy was used to map the electrolyte pH near a copper gas diffusion electrode during CO\u2082 reduction with micron spatial resolution in three dimensions. We observed that the local pH increased from pH 6.8 to greater than pH 10 as the current density was increased from 0 to 28 mA/cm\u00b2 in a 100 mM KHCO\u2083 electrolyte. Variations in the pH across the surface indicate areas of locally increased activity. Within deep trenches of the active layer, the local pH increases as trench width decreases. Computational models confirm these experimental results and also showed that the catalyst found within narrow trenches is more active than that found at the surface of the electrode. This study suggests that the overpotential required to perform selective CO\u2082 reduction can be reduced by increasing the density of narrow trench regions in the microporous layer.", "date": "2021-09-30", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "125", "number": "38", "publisher": "American Chemical Society", "pagerange": "20896-20904", "id_number": "CaltechAUTHORS:20210917-215610705", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210917-215610705", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.1c06265", "primary_object": { "basename": "jp1c06265_si_001.pdf", "url": "https://authors.library.caltech.edu/records/95hh3-zeb55/files/jp1c06265_si_001.pdf" }, "pub_year": "2021", "author_list": "Welch, Alex J.; Fenwick, Aidan Q.; et al." }, { "id": "https://authors.library.caltech.edu/records/ztj05-21j03", "eprint_id": 110397, "eprint_status": "archive", "datestamp": "2023-08-20 04:58:42", "lastmod": "2023-10-23 19:38:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Decoupled electrochemical water-splitting systems: a review and perspective", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 The Royal Society of Chemistry 2021. \n\nSubmitted 24 Apr 2021; Accepted 02 Jul 2021; First published 07 Jul 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. MCM acknowledges a Graduate Research Fellowship from the National Science Foundation. MCM also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nConflicts of interest: NSL may become a consultant and equity holder in a future potential corporation that is seeking funding to focus on commercial development of catalysts and systems for the production and use of hydrogen.", "abstract": "Electrochemical water splitting is a promising technology to renewably generate hydrogen fuel from water. One particular drawback of conventional water splitting is that the hydrogen-forming reduction reaction is tightly coupled, both spatially and temporally, to the oxygen-forming oxidation reaction. This coupling poses challenges in both conventional and direct-solar-powered electrolysis systems, including gas crossover and separator degradation, sometimes necessitating the use of precious metal catalysts. In decoupled water splitting, the conventional electrolysis reactions are separated spatially, temporally, or both, via coupling to an intermediate redox mediator. Decoupled water-splitting systems are flexible and modular by nature, with other proposed benefits including facile coupling to renewable power sources, utilization of earth-abundant catalysts, and intrinsically safe operation. Here we review recent advances in decoupled water splitting and related fields, mainly categorizing decoupled systems by mediator phase and standard potential. We offer insight to how decoupling may be advantageous, and which tradeoffs need to be considered for practical implementation. We conclude our review with discussion of known technological hurdles and note opportunities for future discovery.", "date": "2021-09-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "14", "number": "9", "publisher": "Royal Society of Chemistry", "pagerange": "4740-4759", "id_number": "CaltechAUTHORS:20210823-225400426", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210823-225400426", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/d1ee01226f", "pub_year": "2021", "author_list": "Ifkovits, Zachary P.; Evans, Jake M.; et al." }, { "id": "https://authors.library.caltech.edu/records/dpk8g-eh618", "eprint_id": 110625, "eprint_status": "archive", "datestamp": "2023-08-20 04:58:57", "lastmod": "2025-04-23 01:11:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "van-der-Burgt-Julia-S", "name": { "family": "van der Burgt", "given": "Julia S." } }, { "id": "Needell-David-R", "name": { "family": "Needell", "given": "David R." }, "orcid": "0000-0001-8343-5883" }, { "id": "Veeken-Tom", "name": { "family": "Veeken", "given": "Tom" }, "orcid": "0000-0002-6235-7836" }, { "id": "Polman-Albert", "name": { "family": "Polman", "given": "Albert" }, "orcid": "0000-0002-0685-3886" }, { "id": "Garnett-Erik-C", "name": { "family": "Garnett", "given": "Erik C." }, "orcid": "0000-0002-9158-8326" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Unlocking Higher Power Efficiencies in Luminescent Solar Concentrators through Anisotropic Luminophore Emission", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Absorption, Power conversion efficiency, Solar cells, Quantum mechanics, Gallium arsenide", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: July 3, 2021; Accepted: August 5, 2021; Published: August 19, 2021. \n\nThis work was supported in part by the Engineering Research Center Program of the National Science Foundation and the Office of Energy Efficiency and Renewable Energy of the Department of Energy under NSF Cooperative Agreement no. EEC-1041895 and the Space Solar Power Project. This work is also supported in part by the Dutch Research Council (NWO). This work was carried out in part on the Dutch national e-infrastructure with the support of SURF Cooperative. The authors thank the Resnick Institute for Sustainability at the California Institute of Technology for their continued support. The authors thank Lenneke Slooff for her help with implementing the current record luminescent solar concentrator in the Monte Carlo model. \n\nAuthor Contributions: J.S.v.d.B., D.R.N., and T.V. contributed equally to this work. \n\nThe authors declare no competing financial interest.", "abstract": "The luminescent solar concentrator (LSC) offers a potential pathway for achieving low-cost, fixed-tilt light concentration. Despite decades of research, conversion efficiency for LSC modules has fallen far short of that achievable by geometric concentrators. However, recent advances in anisotropically emitting nanophotonic structures could enable a significant step forward in efficiency. Here, we employ Monte Carlo ray-trace modeling to evaluate the conversion efficiency for anisotropic luminophore emission as a function of photoluminescence quantum yield, waveguide concentration, and geometric gain. By spanning the full LSC parameter space, we define a roadmap toward high conversion efficiency. An analytical function is derived for the dark radiative current of an LSC to calculate the conversion efficiency from the ray-tracing results. We show that luminescent concentrator conversion efficiency can be increased from the current record value of 7.1\u20139.6% by incorporating anisotropy. We provide design parameters for optimized luminescent solar concentrators with practical geometrical gains of 10. Using luminophores with strongly anisotropic emission and high (99%) quantum yield, we conclude that conversion efficiencies beyond 28% are achievable. This analysis reveals that for high LSC performance, waveguide losses are as important as the luminophore quantum yield.", "date": "2021-09-01", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "13", "number": "34", "publisher": "American Chemical Society", "pagerange": "40742-40753", "id_number": "CaltechAUTHORS:20210830-230028706", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210830-230028706", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Space-Solar-Power-Project" } ] }, "doi": "10.1021/acsami.1c12547", "pub_year": "2021", "author_list": "van der Burgt, Julia S.; Needell, David R.; et al." }, { "id": "https://authors.library.caltech.edu/records/v1j0j-w5x68", "eprint_id": 108676, "eprint_status": "archive", "datestamp": "2023-08-22 10:58:17", "lastmod": "2023-10-23 17:14:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saccone-Max-A", "name": { "family": "Saccone", "given": "Max A." }, "orcid": "0000-0003-3846-2908" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Understanding and mitigating mechanical degradation in lithium\u2013sulfur batteries: additive manufacturing of Li\u2082S composites and nanomechanical particle compressions", "ispublished": "pub", "full_text_status": "public", "keywords": "Additive manufacturing; Lithium sulfide; Li\u2013S batteries; Emulsion; Stereolithography; Nanomechanical characterization", "note": "\u00a9 The Author(s), under exclusive licence to The Materials Research Society 2021. \n\nReceived 22 January 2021; Accepted 19 March 2021; Published 09 April 2021. \n\nThe authors would like to acknowledge the following people: Professor K. See for productive discussions, use of the glovebox, and coin cell materials. J. H. Kang for assistance with TGA. C. Ma for assistance with SEM/EDS. H. Zhang and B. Edwards for assistance with nanomechanical measurements. \n\nThis work was supported by the Resnick Sustainability Institute. \n\nData availability: The data and code generated and/or analyzed during the current study are available from the corresponding author on reasonable request. \n\nAuthor Contributions: MAS and JRG conceived of and designed the experiments. MAS performed the experiments. MAS and JRG wrote the manuscript.\n\nThe authors declare no conflicts of interest.\n\n

Supplemental Material - 43578_2021_182_MOESM1_ESM.docx

", "abstract": "Lithium\u2013sulfur batteries are poised to outcompete lithium-ion batteries in key sectors such as transportation and grid storage due to the low cost and high theoretical energy density of sulfur as a cathode material. Widespread implementation of this technology is hindered by significant degradation during cycling, including mechanical failure via cracking or detachment of insulating lithium sulfide (Li\u2082S) from the conductive matrix in the cathode, causing irreversible capacity fade. We developed a technique to additively manufacture Li\u2082S composites to fabricate rationally designed cathodes and demonstrate the utility of a three dimensionally architected Li\u2082S composite cathode in a battery. We additionally measure the yet unknown material properties and deformation mechanisms of Li\u2082S powders via in situ scanning electron microscope (SEM) nanomechanical experiments. Measuring these mechanical properties is a first step towards understanding the process of mechanical degradation and is necessary to enable the rational design of high energy density, long-cycling, and mechanically robust sulfur cathodes.", "date": "2021-09", "date_type": "published", "publication": "Journal of Materials Research", "volume": "36", "number": "18", "publisher": "Materials Research Society", "pagerange": "3656-3666", "id_number": "CaltechAUTHORS:20210409-123059226", "issn": "0884-2914", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210409-123059226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1557/s43578-021-00182-w", "primary_object": { "basename": "43578_2021_182_MOESM1_ESM.docx", "url": "https://authors.library.caltech.edu/records/v1j0j-w5x68/files/43578_2021_182_MOESM1_ESM.docx" }, "pub_year": "2021", "author_list": "Saccone, Max A. and Greer, Julia R." }, { "id": "https://authors.library.caltech.edu/records/5epx3-x6t87", "eprint_id": 104240, "eprint_status": "archive", "datestamp": "2023-08-20 04:50:02", "lastmod": "2025-11-18 21:50:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guo-Linqi", "name": { "family": "Guo", "given": "Linqi" }, "orcid": "0000-0001-5771-2752" }, { "id": "Liang-Chen", "name": { "family": "Liang", "given": "Chen" }, "orcid": "0000-0002-0015-7206" }, { "id": "Zocca-Alessandro", "name": { "family": "Zocca", "given": "Alessandro" }, "orcid": "0000-0001-6585-4785" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" } } ] }, "title": "Line Failure Localization of Power Networks Part II: Cut Set Outages", "ispublished": "pub", "full_text_status": "public", "keywords": "Cascading failure, Laplacian matrix, contingency analysis, spanning forests", "note": "\u00a9 2021 IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. \n\nManuscript received May 27, 2020; revised November 1, 2020 and January 19, 2021; accepted March 1, 2021. Date of publication April 13, 2021; date of current version August 19, 2021. \n\nThis work was supported by Resnick Fellowship, Linde Institute Research Award, NWO Rubicon under Grant 680.50.1529, and by NSF under Grants CCF 1637598, ECCS 1619352, ECCS 1931662, CNS 1545096, CNS 1518941, CPS ECCS 1739355, and CPS 154471. \n\nPaper no. TPWRS-00762-2020.\n\n

Published - Line_Failure_Localization_of_Power_Networks_Part_II_Cut_Set_Outages.pdf

Submitted - 2005.11320.pdf

", "abstract": "Transmission line failure in power systems prop-agate non-locally, making the control of the resulting outages extremely difficult. In Part II of this paper, we continue the study of line failure localizability in transmission networks and characterize the impact of cut set outages. We establish a Simple Path Criterion, showing that the propagation pattern due to bridge outages, a special case of cut set failures, are fully determined by the positions in the network of the buses that participate in load balancing. We then extend our results to general cut set outages. In contrast to non-cut outages discussed in Part I whose subsequent line failures are contained within the original blocks, cut set outages typically impact the whole network, affecting the power flows on all remaining lines. We corroborate our analytical results in both parts using the IEEE 118-bus test system, in which the failure propagation patterns exhibit a clear block-diagonal structure predicted by our theory, even when using full AC power flow equations.", "date": "2021-09", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "36", "number": "5", "publisher": "IEEE", "pagerange": "4152-4160", "id_number": "CaltechAUTHORS:20200707-095927831", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200707-095927831", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Linde Institute of Economic and Management Science" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "680.50.1529" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "ECCS-1619352" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "NSF", "grant_number": "CNS-1545096" }, { "agency": "NSF", "grant_number": "CNS-1518941" }, { "agency": "NSF", "grant_number": "ECCS-1739355" }, { "agency": "NSF", "grant_number": "CPS-154471" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2021.3068048", "primary_object": { "basename": "2005.11320.pdf", "url": "https://authors.library.caltech.edu/records/5epx3-x6t87/files/2005.11320.pdf" }, "related_objects": [ { "basename": "Line_Failure_Localization_of_Power_Networks_Part_II_Cut_Set_Outages.pdf", "url": "https://authors.library.caltech.edu/records/5epx3-x6t87/files/Line_Failure_Localization_of_Power_Networks_Part_II_Cut_Set_Outages.pdf" } ], "pub_year": "2021", "author_list": "Guo, Linqi; Liang, Chen; et al." }, { "id": "https://authors.library.caltech.edu/records/xtnd5-5ye52", "eprint_id": 104242, "eprint_status": "archive", "datestamp": "2023-08-20 04:50:12", "lastmod": "2023-10-20 19:12:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guo-Linqi", "name": { "family": "Guo", "given": "Linqi" }, "orcid": "0000-0001-5771-2752" }, { "id": "Liang-Chen", "name": { "family": "Liang", "given": "Chen" }, "orcid": "0000-0002-0015-7206" }, { "id": "Zocca-Alessandro", "name": { "family": "Zocca", "given": "Alessandro" }, "orcid": "0000-0001-6585-4785" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" } } ] }, "title": "Line Failure Localization of Power Networks Part I: Non-Cut Outages", "ispublished": "pub", "full_text_status": "public", "keywords": "Cascading failure, Laplacian matrix, contingency analysis, spanning forests", "note": "\u00a9 2021 IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. \n\nManuscript received May 27, 2020; revised November 1, 2020 and January 19, 2021; accepted March 1, 2021. Date of publication March 17, 2021; date of current version August 19, 2021. \n\nThis work has been supported by Resnick Fellowship, Linde Institute Research Award, NWO Rubicon under Grant 680.50.1529, NSF through Grants CCF 1637598, ECCS 1619352, ECCS 1931662, CNS 1545096, CNS 1518941, CPS ECCS 1739355, CPS 154471. \n\nPaper no. TPWRS-00882-2020.\n\n

Published - Line_Failure_Localization_of_Power_Networks_Part_I_Non-Cut_Outages.pdf

Submitted - 2005.10199.pdf

", "abstract": "Transmission line failures in power systems propagate non-locally, making the control of the resulting outages extremely difficult. In this work, we establish a mathematical theory that characterizes the patterns of line failure propagation and localization in terms of network graph structure. It provides a novel perspective on distribution factors that precisely captures Kirchhoff's Law in terms of topological structures. Our results show that the distribution of specific collections of subtrees of the transmission network plays a critical role on the patterns of power redistribution, and motivates the block decomposition of the transmission network as a structure to understand long-distance propagation of disturbances. In Part I of this paper, we present the case when the post-contingency network remains connected after an initial set of lines are disconnected simultaneously. In Part II, we present the case when an outage separates the network into multiple islands.", "date": "2021-09", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "36", "number": "5", "publisher": "IEEE", "pagerange": "4140-4151", "id_number": "CaltechAUTHORS:20200707-101019648", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200707-101019648", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Ronald And Maxine Linde Center for Global Environmental Science" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "680.50.1529" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "ECCS-1619352" }, { "agency": "NSF", "grant_number": "ECCS-1931662" }, { "agency": "NSF", "grant_number": "CNS-1545096" }, { "agency": "NSF", "grant_number": "CNS-1518941" }, { "agency": "NSF", "grant_number": "ECCS-1739355" }, { "agency": "NSF", "grant_number": "CPS-154471" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/tpwrs.2021.3066336", "primary_object": { "basename": "2005.10199.pdf", "url": "https://authors.library.caltech.edu/records/xtnd5-5ye52/files/2005.10199.pdf" }, "related_objects": [ { "basename": "Line_Failure_Localization_of_Power_Networks_Part_I_Non-Cut_Outages.pdf", "url": "https://authors.library.caltech.edu/records/xtnd5-5ye52/files/Line_Failure_Localization_of_Power_Networks_Part_I_Non-Cut_Outages.pdf" } ], "pub_year": "2021", "author_list": "Guo, Linqi; Liang, Chen; et al." }, { "id": "https://authors.library.caltech.edu/records/f00wy-s1473", "eprint_id": 108942, "eprint_status": "archive", "datestamp": "2023-08-20 04:50:57", "lastmod": "2023-10-20 23:20:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Zachary-J", "name": { "family": "Lee", "given": "Zachary J." }, "orcid": "0000-0002-5358-2388" }, { "id": "Lee-George-S", "name": { "family": "Lee", "given": "George" } }, { "id": "Lee-Ted", "name": { "family": "Lee", "given": "Ted" }, "orcid": "0000-0002-5793-7457" }, { "id": "Jin-Cheng-S", "name": { "family": "Jin", "given": "Cheng" } }, { "id": "Lee-Rand", "name": { "family": "Lee", "given": "Rand" } }, { "id": "Low-Zhi-H", "name": { "family": "Low", "given": "Zhi" }, "orcid": "0000-0003-4962-7771" }, { "id": "Chang-Daniel", "name": { "family": "Chang", "given": "Daniel" } }, { "id": "Ortega-Christine", "name": { "family": "Ortega", "given": "Christine" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Adaptive Charging Networks: A Framework for Smart Electric Vehicle Charging", "ispublished": "pub", "full_text_status": "public", "keywords": "Electric vehicles (EVs), cyber-physical systems, distributed energy resources, model predictive control, smart charging", "note": "\u00a9 2021 IEEE. This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/. \n\nManuscript received August 13, 2020; revised February 18, 2021; accepted April 2, 2021. Date of publication April 20, 2021; date of current version August 23, 2021. \n\nThis work was supported in part by the National Science Foundation through the Graduate Research Fellowship Program under Grant 1745301; in part by NSF AIR-TT under Grant 1602119; in part by NSF Division of Electrical, Communications and Cyber Systems (ECCS) under Grant 1932611; and in part by NSF Division of Computing and Communication Foundations (CCF) under Grant 1637598; in part by the Resnick Sustainability Institute Graduate Fellowship; in part by Caltech Rocket Fund; in part by Caltech CI2 Grant; in part by the Emerging Technologies Coordinating Council of Utilities; and in part by Well Fargo/NREL IN2. Paper no. TSG-01250-2020.\n\n

Published - Adaptive_Charging_Networks_A_Framework_for_Smart_Electric_Vehicle_Charging.pdf

Submitted - 2012.02636.pdf

", "abstract": "We describe the architecture and algorithms of the Adaptive Charging Network (ACN), which was first deployed on the Caltech campus in early 2016 and is currently operating at over 100 other sites in the United States. The architecture enables real-time monitoring and control and supports electric vehicle (EV) charging at scale. The ACN adopts a flexible Adaptive Scheduling Algorithm based on convex optimization and model predictive control and allows for significant over-subscription of electrical infrastructure. We describe some of the practical challenges in real-world charging systems, including unbalanced three-phase infrastructure, non-ideal battery charging behavior, and quantized control signals. We demonstrate how the Adaptive Scheduling Algorithm handles these challenges, and compare its performance against baseline algorithms from the deadline scheduling literature using real workloads recorded from the Caltech ACN and accurate system models. We find that in these realistic settings, our scheduling algorithm can improve operator profit by 3.4 times over uncontrolled charging and consistently outperforms baseline algorithms when delivering energy in highly congested systems.", "date": "2021-09", "date_type": "published", "publication": "IEEE Transactions on Smart Grid", "volume": "12", "number": "5", "publisher": "IEEE", "pagerange": "4339-4350", "id_number": "CaltechAUTHORS:20210503-115705210", "issn": "1949-3053", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210503-115705210", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "IIP-1602119" }, { "agency": "NSF", "grant_number": "ECCS-1932611" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech RocketFund" }, { "agency": "Caltech Innovation Initiative (CI2)" }, { "agency": "Emerging Technologies Coordinating Council of Utilities" }, { "agency": "Wells Fargo Innovation Incubator (IN2)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TSG.2021.3074437", "primary_object": { "basename": "2012.02636.pdf", "url": "https://authors.library.caltech.edu/records/f00wy-s1473/files/2012.02636.pdf" }, "related_objects": [ { "basename": "Adaptive_Charging_Networks_A_Framework_for_Smart_Electric_Vehicle_Charging.pdf", "url": "https://authors.library.caltech.edu/records/f00wy-s1473/files/Adaptive_Charging_Networks_A_Framework_for_Smart_Electric_Vehicle_Charging.pdf" } ], "pub_year": "2021", "author_list": "Lee, Zachary J.; Lee, George; et al." }, { "id": "https://authors.library.caltech.edu/records/q9rjh-5yb85", "eprint_id": 110641, "eprint_status": "archive", "datestamp": "2023-08-20 04:48:01", "lastmod": "2023-10-23 19:46:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bailey-Gwendolyn-A", "name": { "family": "Bailey", "given": "Gwendolyn A." }, "orcid": "0000-0002-6636-4128" }, { "id": "Buss-Joshua-A", "name": { "family": "Buss", "given": "Joshua A." }, "orcid": "0000-0002-3347-8583" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Terminal, Open-Shell Mo Carbide and Carbyne Complexes: Spin Delocalization and Ligand Noninnocence", "ispublished": "pub", "full_text_status": "public", "keywords": "Ligands, Delocalization, Inorganic carbon compounds, Quantum mechanics, Energy levels", "note": "\u00a9 2021 American Chemical Society. \n\nReceived 11 April 2021. Published online 11 August 2021. Published in issue 25 August 2021. \n\nWe thank Lawrence Henling, Michael Takase, and Manar Shoshani for invaluable crystallographic assistance. Lawrence Henling is also thanked for assistance with elemental analysis. G.A.B. is grateful to NSERC of Canada and the Resnick Sustainability Institute at Caltech for fellowship support. J.A.B. is grateful for an NSF graduate research fellowship. We thank the NSF (CHE-1800501), the Dow Next Generation Education Fund (instrumentation), and Caltech for funding. \n\nThe authors declare no competing financial interest. \n\nAccession Codes. CCDC 2076055, 2076057\u20132076058, and 2076060 contain the supplementary crystallographic data for this paper.\n\n

Supplemental Material - ja1c03806_si_001.pdf

", "abstract": "Open-shell compounds bearing metal\u2013carbon triple bonds, such as carbides and carbynes, are of significant interest as plausible intermediates in the reductive catenation of C\u2081 oxygenates. Despite the abundance of closed-shell carbynes reported, open-shell variants are very limited, and an open-shell carbide has yet to be reported. Herein, we report the synthesis of the first terminal, open-shell carbide complexes, [K][1] and [1][BAr^F\u2084] (1 = P2Mo(\u2261C:)(CO), P2 = a terphenyl diphosphine ligand), which differ by two redox states, as well as a series of related open-shell carbyne complexes. The complexes are characterized by single-crystal X-ray diffraction and NMR, EPR, and IR spectroscopies, while the electronic structures are probed by EPR studies and DFT calculations to assess spin delocalization. In the d\u2081 complexes, the spin is primarily localized on the metal (\u223c55\u201377% Mo d_(xy)) with delocalization on the triply bonded carbon of \u223c0.05\u20130.09 e\u207b. In the reduced carbide [K][1], a direct metal\u2013arene interaction enables ancillary ligand reduction, resulting in reduced radical character on the terminal carbide (\u2a7d0.02 e\u207b). Reactivity studies with [K][1] reveal the formation of mixed-valent C\u2013C coupled products at \u221240 \u00b0C, illustrating how productive reactivity manifolds can be engendered through the manipulation of redox states. Combined, the results inform on the electronic structure and reactivity of a new and underrepresented class of compounds with potential significance to a wide array of reactions involving open-shell species.", "date": "2021-08-25", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "33", "publisher": "American Chemical Society", "pagerange": "13091-13102", "id_number": "CaltechAUTHORS:20210831-200226268", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210831-200226268", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "NSF", "grant_number": "CHE-1800501" }, { "agency": "Dow Next Generation Education Fund" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.1c03806", "primary_object": { "basename": "ja1c03806_si_001.pdf", "url": "https://authors.library.caltech.edu/records/q9rjh-5yb85/files/ja1c03806_si_001.pdf" }, "pub_year": "2021", "author_list": "Bailey, Gwendolyn A.; Buss, Joshua A.; et al." }, { "id": "https://authors.library.caltech.edu/records/2vdej-70453", "eprint_id": 110627, "eprint_status": "archive", "datestamp": "2023-08-20 04:46:41", "lastmod": "2023-10-23 19:45:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bailey-Gwendolyn-A", "name": { "family": "Bailey", "given": "Gwendolyn A." }, "orcid": "0000-0002-6636-4128" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Terminal Mo Carbide and Carbyne Reactivity: H\u2082 Cleavage, B\u2013C Bond Activation, and C\u2013C Coupling", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbene compounds, Ligands, Chemical reactions, Inorganic carbon compounds, Reactivity", "note": "\u00a9 2021 American Chemical Society. \n\nReceived 6 June 2021. Published online 12 August 2021. Published in issue 23 August 2021. \n\nWe thank Lawrence Henling and Michael Takase for invaluable crystallographic assistance. G.A.B. is grateful to the NSERC of Canada and the Resnick Sustainability Institute at Caltech for fellowship support. We thank the the NSF (CHE-1800501), the Dow Next Generation Education Fund (instrumentation), and Caltech for funding. \n\nThe authors declare no competing financial interest. \n\nCCDC 2000078\u20132000079 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif.\n\n

Supplemental Material - om1c00336_si_001.xyz

Supplemental Material - om1c00336_si_002.pdf

", "abstract": "Transition-metal carbides have been posited as intermediates in the upgrading of C\u2081 feedstocks, including the Fischer\u2013Tropsch synthesis of higher olefins from CO and H\u2082. Still, molecular examples remain rare, and their reactivity is poorly understood. In a molecular platform supported by a flexible terphenyl diphosphine ligand, the important C\u2013C coupling step was previously demonstrated on the reaction of Mo carbide and carbene species with CO. Methylidyne and methylidene complexes were accessible on sequential treatment of the carbide with sources of H\u207a and H\u207b, surrogates for heterolyzed H\u2082. Herein, we demonstrate that the terminal carbide complex is also capable of directly activating H\u2082, yielding a P\u2013C-bonded ylide complex. The carbide moiety also inserts into the B\u2013C bond of triphenylborane, yielding an unusual example of a borylcarbene with a direct Mo\u2013B contact. C\u2013C coupling from the terminal methylidyne, a potential intermediate formed on heterolytic H\u2082 cleavage and H\u207a transfer to the carbide, yields a Mo ketenyl complex, thus giving information for the first time on the relative rates of coupling from carbide, carbyne, and carbene species in the same molecular platform.", "date": "2021-08-23", "date_type": "published", "publication": "Organometallics", "volume": "40", "number": "16", "publisher": "American Chemical Society", "pagerange": "2881-2887", "id_number": "CaltechAUTHORS:20210830-230028871", "issn": "0276-7333", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210830-230028871", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1800501" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.organomet.1c00336", "primary_object": { "basename": "om1c00336_si_001.xyz", "url": "https://authors.library.caltech.edu/records/2vdej-70453/files/om1c00336_si_001.xyz" }, "related_objects": [ { "basename": "om1c00336_si_002.pdf", "url": "https://authors.library.caltech.edu/records/2vdej-70453/files/om1c00336_si_002.pdf" } ], "pub_year": "2021", "author_list": "Bailey, Gwendolyn A. and Agapie, Theodor" }, { "id": "https://authors.library.caltech.edu/records/snxqn-hhd66", "eprint_id": 113693, "eprint_status": "archive", "datestamp": "2023-08-22 10:31:20", "lastmod": "2025-11-18 22:51:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Huan", "name": { "family": "Zhang", "given": "Huan" } }, { "id": "Cao-Yuhong", "name": { "family": "Cao", "given": "Yuhong" } }, { "id": "Xu-Dawei", "name": { "family": "Xu", "given": "Dawei" } }, { "id": "Goh-Natalie-S", "name": { "family": "Goh", "given": "Natalie S." } }, { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" }, { "id": "Cestellos-Blanco-Stefano", "name": { "family": "Cestellos-Blanco", "given": "Stefano" } }, { "id": "Cheng-Yuan", "name": { "family": "Cheng", "given": "Yuan" } }, { "id": "Landry-Markita-P", "name": { "family": "Landry", "given": "Markita P." }, "orcid": "0000-0002-5832-8522" }, { "id": "Yang-Peidong", "name": { "family": "Yang", "given": "Peidong" }, "orcid": "0000-0003-4799-1684" } ] }, "title": "Gold-Nanocluster-Mediated Delivery of siRNA to Intact Plant Cells for Efficient Gene Knockdown", "ispublished": "pub", "full_text_status": "public", "keywords": "gold nanoclusters; siRNA; delivery; gene silencing; plants; Mechanical Engineering; Condensed Matter Physics; General Materials Science; General Chemistry; Bioengineering", "note": "\u00a9 2021 American Chemical Society. \n\nReceived 11 May 2021. Revised 17 June 2021. Published online 21 June 2021. Published in issue 14 July 2021. \n\nWe acknowledge support from a Burroughs Wellcome Fund Career Award at the Scientific Interface (CASI), a Stanley Fahn PDF Junior Faculty Grant under award no. PF-JFA-1760, a Beckman Foundation Young Investigator Award, a USDA AFRI award, a grant from the Gordon and Betty Moore Foundation, a USDA NIFA award, a USDA-BBT EAGER award, an NSF CAREER award, the Dreyfus Foundation, the Chan-Zuckerberg foundation, and an FFAR New Innovator Award (to M.P.L.). Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors acknowledge the support of the BASF-CARA program. We acknowledge support from the Keck Foundation (Grant 89208), and H.Z. acknowledges the support of the start-up fund from Jinan University (88016105). N.S.G. is supported by a Foundation for Food and Agriculture Research Fellowship. G.S.D. is supported by a Schlumberger Foundation Faculty for the Future Fellowship and the Resnick Sustainability Institute. The authors also acknowledge support from the UC Berkeley Molecular Imaging Center (supported by the Gordon and Betty Moore Foundation), the QB3 Shared Stem Cell Facility, and the Innovative Genomics Institute (IGI). \n\nAuthor Contributions:\nH.Z. and Y.C. contributed equally to this work.\n\nYuhong C., H.Z., M.P.L., and P.Y. conceived the idea and\ndesigned the study. H.Z. and Yuhong C. performed the\nmajority of the experiments and data analysis. H.Z., Yuhong C,\nS.C.-B., M.P.L., and P.Y. wrote or revised the manuscript. D.X.\nassisted in gold nanocluster synthesis. Yuan C. helped with\nplant seeding and maintenance. G.S.D and N.S.G. helped\nanalyze the results. All authors edited the manuscript and\napproved the final version.\n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl1c01792_si_001.pdf

Supplemental Material - nl1c01792_si_002.pdf

", "abstract": "RNA interference, which involves the delivery of small interfering RNA (siRNA), has been used to validate target genes, to understand and control cellular metabolic pathways, and to use as a \"green\" alternative to confer pest tolerance in crops. Conventional siRNA delivery methods such as viruses and Agrobacterium-mediated delivery exhibit plant species range limitations and uncontrolled DNA integration into the plant genome. Here, we synthesize polyethylenimine-functionalized gold nanoclusters (PEI-AuNCs) to mediate siRNA delivery into intact plants and show that these nanoclusters enable efficient gene knockdown. We further demonstrate that PEI-AuNCs protect siRNA from RNase degradation while the complex is small enough to bypass the plant cell wall. Consequently, AuNCs enable gene knockdown with efficiencies of up 76.5 \u00b1 5.9% and 76.1 \u00b1 9.5% for GFP and ROQ1, respectively, with no observable toxicity. Our data suggest that AuNCs can deliver siRNA into intact plant cells for broad applications in plant biotechnology.", "date": "2021-07-14", "date_type": "published", "publication": "Nano Letters", "volume": "21", "number": "13", "publisher": "American Chemical Society", "pagerange": "5859-5866", "id_number": "CaltechAUTHORS:20220302-323745000", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220302-323745000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Burroughs Wellcome Fund" }, { "agency": "Parkinson's Foundation", "grant_number": "PF-JFA-1760" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Department of Agriculture" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "NSF" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Chan-Zuckerberg Foundation" }, { "agency": "Foundation for Food Research" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "W. M. Keck Foundation", "grant_number": "89208" }, { "agency": "Jinan University", "grant_number": "88016105" }, { "agency": "Schlumberger Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Innovative Genomics Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.1c01792", "primary_object": { "basename": "nl1c01792_si_001.pdf", "url": "https://authors.library.caltech.edu/records/snxqn-hhd66/files/nl1c01792_si_001.pdf" }, "related_objects": [ { "basename": "nl1c01792_si_002.pdf", "url": "https://authors.library.caltech.edu/records/snxqn-hhd66/files/nl1c01792_si_002.pdf" } ], "pub_year": "2021", "author_list": "Zhang, Huan; Cao, Yuhong; et al." }, { "id": "https://authors.library.caltech.edu/records/w5ppg-n5n92", "eprint_id": 101280, "eprint_status": "archive", "datestamp": "2023-08-22 10:17:05", "lastmod": "2023-10-23 16:56:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" } }, { "id": "Lu-I-Te", "name": { "family": "Lu", "given": "I-Te" } }, { "id": "Maliyov-Ivan", "name": { "family": "Maliyov", "given": "Ivan" } }, { "id": "Tong-Xiao", "name": { "family": "Tong", "given": "Xiao" } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Perturbo: A software package for ab initio electron\u2013phonon interactions, charge transport and ultrafast dynamics", "ispublished": "pub", "full_text_status": "public", "keywords": "Charge transport; Ultrafast dynamics; Electron\u2013phonon interactions; Wannier functions", "note": "\u00a9 2021 Elsevier B.V. \n\nReceived 7 February 2020, Accepted 28 February 2021, Available online 22 March 2021. \n\nThe review of this paper was arranged by Prof. D.P. Landau. \n\nWe thank V.A. Jhalani and B.K. Chang for fruitful discussions. This work was supported by the National Science Foundation, United States under Grants No. ACI-1642443 for code development and DMR-1750613 for theory development. J.-J.Z. acknowledges support by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy, United States under Award No. DE-SC0004993. J.P. acknowledges support by the Korea Foundation for Advanced Studies, South Korea. I-T.L. was supported by the Air Force Office of Scientific Research through the Young Investigator Program, Grant FA9550-18-1-0280. X.T. was supported by the Resnick Institute at Caltech. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy, United States under Contract No. DE-AC02-05CH11231. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\n

Submitted - 2002.02045.pdf

", "abstract": "Perturbo is a software package for first-principles calculations of charge transport and ultrafast carrier dynamics in materials. The current version focuses on electron\u2013phonon interactions and can compute phonon-limited transport properties such as the conductivity, carrier mobility and Seebeck coefficient. It can also simulate the ultrafast nonequilibrium electron dynamics in the presence of electron\u2013phonon scattering. Perturbo uses results from density functional theory and density functional perturbation theory calculations as input, and employs Wannier interpolation to reduce the computational cost. It supports norm-conserving and ultrasoft pseudopotentials, spin\u2013orbit coupling, and polar electron\u2013phonon interactions for bulk and 2D materials. Hybrid MPI plus OpenMP parallelization is implemented to enable efficient calculations on large systems (up to at least 50 atoms) using high-performance computing. Taken together, Perturbo provides efficient and broadly applicable ab initio tools to investigate electron\u2013phonon interactions and carrier dynamics quantitatively in metals, semiconductors, insulators, and 2D materials. \n\nProgram summary: \n\nProgram Title: Perturbo; \n\nCPC Library link to program files: https://doi.org/10.17632/34m2p6v79t.1; \n\nDeveloper's repository link: https://perturbo-code.github.io; \n\nLicensing provisions: GNU General Public Licence 3.0;\n\nProgramming language: Fortran, Python; \n\nExternal routines/libraries: LAPACK, HDF5, MPI, OpenMP, FFTW, Quantum-ESPRESSO, Wannier90; \n\nNature of problem: Computing transport properties from first-principles in materials, including the electrical conductivity, carrier mobility and Seebeck coefficient; Simulating ultrafast nonequilibrium electron dynamics, such as the relaxation of excited carriers via interactions with phonons. \n\nSolution method: We implement the first-principles Boltzmann transport equation, which employs materials properties such as the electronic structure, lattice dynamics, and electron\u2013phonon collision terms computed with density functional theory and density functional perturbation theory. The Boltzmann transport equation is solved numerically to compute charge transport and simulate ultrafast carrier dynamics. Wannier interpolation is employed to reduce the computational cost. \n\nAdditional comments: Hybrid MPI plus OpenMP parallelization is implemented to run large calculations and take advantage of high-performance computing. Most results are output to HDF5 file format, which is portable and convenient for post-processing using high-level languages such as Python and Julia.", "date": "2021-07", "date_type": "published", "publication": "Computer Physics Communications", "volume": "264", "publisher": "Elsevier", "pagerange": "Art. No. 107970", "id_number": "CaltechAUTHORS:20200213-150248226", "issn": "0010-4655", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200213-150248226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.cpc.2021.107970", "primary_object": { "basename": "2002.02045.pdf", "url": "https://authors.library.caltech.edu/records/w5ppg-n5n92/files/2002.02045.pdf" }, "pub_year": "2021", "author_list": "Zhou, Jin-Jian; Park, Jinsoo; et al." }, { "id": "https://authors.library.caltech.edu/records/th6fn-fed46", "eprint_id": 109602, "eprint_status": "archive", "datestamp": "2023-08-20 03:52:30", "lastmod": "2023-10-23 18:04:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Derosa-Joseph", "name": { "family": "Derosa", "given": "Joseph" }, "orcid": "0000-0001-8672-4875" }, { "id": "Garrido-Barros-Pablo", "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Electrocatalytic Reduction of C\u2013C \u03c0-Bonds via a Cobaltocene-Derived Concerted Proton\u2013Electron Transfer Mediator: Fumarate Hydrogenation as a Model Study", "ispublished": "pub", "full_text_status": "public", "keywords": "Catalytic reactions, Redox reactions, Aromatic compounds, Evolution reactions, Reaction mechanisms", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: March 29, 2021; Published: June 17, 2021. \n\nThe authors are grateful to the U.S. Department of Energy, Office of Basic Energy Sciences, for support via Grant DE-SC0019136 and also to the American Chemical Society Petroleum Research Fund (61951-ND3). J.D. thanks the Arnold and Mabel Beckman Foundation for a postdoctoral fellowship, and P.G.-B thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship. J.C.P. is grateful to the Resnick Sustainability Institute. We thank a reviewer for helpful feedback regarding proposed intermediates. \n\nAuthor Contributions. J.D. and P.G.-B. contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja1c03335_si_001.pdf

", "abstract": "Reductive concerted proton\u2013electron transfer (CPET) is poorly developed for the reduction of C\u2013C \u03c0-bonds, including for activated alkenes that can succumb to deleterious pathways (e.g., a competing hydrogen evolution reaction or oligomerization) in a standard electrochemical reduction. We demonstrate herein that selective hydrogenation of the C\u2013C \u03c0-bond of fumarate esters can be achieved via electrocatalytic CPET (eCPET) using a CPET mediator comprising cobaltocene with a tethered Br\u00f8nsted base. High selectivity for electrocatalytic hydrogenation is observed only when the mediator is present. Mechanistic analysis sheds light on two distinct kinetic regimes based on the substrate concentration: low fumarate concentrations operate via rate-limiting CPET followed by an electron-transfer/proton-transfer (ET/PT) step, whereas high concentrations operate via CPET followed by a rate-limiting ET/PT step.", "date": "2021-06-30", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "25", "publisher": "American Chemical Society", "pagerange": "9303-9307", "id_number": "CaltechAUTHORS:20210626-183439518", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210626-183439518", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019136" }, { "agency": "American Chemical Society Petroleum Research Fund", "grant_number": "61951-ND3" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Fundaci\u00f3n Ram\u00f3n Areces" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.1c03335", "primary_object": { "basename": "ja1c03335_si_001.pdf", "url": "https://authors.library.caltech.edu/records/th6fn-fed46/files/ja1c03335_si_001.pdf" }, "pub_year": "2021", "author_list": "Derosa, Joseph; Garrido-Barros, Pablo; et al." }, { "id": "https://authors.library.caltech.edu/records/yxbr3-p9084", "eprint_id": 109303, "eprint_status": "archive", "datestamp": "2023-08-22 10:03:30", "lastmod": "2023-10-23 16:54:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chadwick-Austin-J", "name": { "family": "Chadwick", "given": "A. J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "M. P." }, "orcid": "0000-0002-5701-0504" } ] }, "title": "Climate-Change Controls on River Delta Avulsion Location and Frequency", "ispublished": "pub", "full_text_status": "public", "keywords": "River deltas; River avulsions; Climate change; Sea-level rise; Sediment supply; Floods", "note": "\u00a9 2021 American Geophysical Union. \n\nIssue Online: 23 June 2021; Version of Record online: 23 June 2021; Accepted manuscript online: 24 May 2021; Manuscript accepted: 18 May 2021; Manuscript revised: 14 May 2021; Manuscript received: 10 November 2020. \n\nThe authors thank Vamsi Ganti, Andrew Moodie, Gary Parker, and Brad Murray for useful discussions. The authors acknowledge NSF Grant EAR 1427262 and the Resnick Sustainability Institute at the California Institute of Technology for support. \n\nThe authors declare no conflict of interest. \n\nData Availability Statement: The data and model code underlying this study are publicly available in the SEAD repository (http://doi.org/10.26009/s0VZMEPD) and Zenodo (https://doi.org/10.5281/zenodo.4265479) respectively.\n\n

Published - 2020JF005950.pdf

Supplemental Material - downloadSupplement_doi=10.1029_2F2020JF005950_file=2020JF005950-sup-0001-Supporting+Information+SI-S01.docx

", "abstract": "Coastal rivers that build deltas undergo repeated avulsion events\u2014that is, abrupt changes in river course\u2014which we need to understand to predict land building and flood hazards in coastal landscapes. Climate change can impact water discharge, flood frequency, sediment supply, and sea level, all of which could impact avulsion location and frequency. Here we present results from quasi-2D morphodynamic simulations of repeated delta-lobe construction and avulsion to explore how avulsion location and frequency are affected by changes in relative sea level, sediment supply, and flood regime. Model results indicate that relative sea-level rise drives more frequent avulsions that occur at a distance from the shoreline set by backwater hydrodynamics. Reducing the sediment supply relative to transport capacity has little impact on deltaic avulsions, because, despite incision in the upstream trunk channel, deltas can still aggrade as a result of progradation. However, increasing the sediment supply relative to transport capacity can shift avulsions upstream of the backwater zone because aggradation in the trunk channel outpaces progradation-induced delta aggradation. Increasing frequency of overbank floods causes less frequent avulsions because floods scour the riverbed within the backwater zone, slowing net aggradation rates. Results provide a framework to assess upstream and downstream controls on avulsion patterns over glacial-interglacial cycles, and the impact of land use and anthropogenic climate change on deltas.", "date": "2021-06", "date_type": "published", "publication": "Journal of Geophysical Research. Earth Surface", "volume": "126", "number": "6", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020JF005950", "id_number": "CaltechAUTHORS:20210528-094925804", "issn": "2169-9003", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210528-094925804", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020JF005950", "primary_object": { "basename": "2020JF005950.pdf", "url": "https://authors.library.caltech.edu/records/yxbr3-p9084/files/2020JF005950.pdf" }, "pub_year": "2021", "author_list": "Chadwick, A. J. and Lamb, M. P." }, { "id": "https://authors.library.caltech.edu/records/mdzkc-wzn51", "eprint_id": 109173, "eprint_status": "archive", "datestamp": "2023-08-20 03:21:02", "lastmod": "2023-10-23 17:42:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zott-Michael-D", "name": { "family": "Zott", "given": "Michael D." }, "orcid": "0000-0003-0535-0512" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Enhanced Ammonia Oxidation Catalysis by a Low-Spin Iron Complex Featuring Cis Coordination Sites", "ispublished": "pub", "full_text_status": "public", "keywords": "Iron, Ligands, Ammonia, Catalysts, Oxidation", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: February 28, 2021; Published: May 17, 2021. \n\nAccession Codes: CCDC 2065372\u22122065373 contain the supplementary crystallographic data for this paper. \n\nThe authors thank the National Institutes of Health (NIH GM070757). M.D.Z. acknowledges the Resnick Sustainability Institute at Caltech and NSF for support via Graduate Fellowships. The Beckman Institute at Caltech supports the X-ray crystallography facility. We also acknowledge Dr. Matthew J. Chalkley and Dr. Pablo Garrido-Barros for insightful discussions. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1716691.pdf

Supplemental Material - ja1c02232_si_001.pdf

", "abstract": "The goal of using ammonia as a solar fuel motivates the development of selective ammonia oxidation (AO) catalysts for fuel cell applications. Herein, we describe Fe-mediated AO electrocatalysis with [(bpyPy\u2082Me)Fe(MeCN)\u2082]\u00b2\u207a, exhibiting the highest turnover number (TON) reported to date for a molecular system. To improve on our recent report of a related iron AO electrocatalyst, [(TPA)Fe(MeCN)\u2082]\u00b2\u207a (TON of 16), the present [(bpyPy\u2082Me)Fe(MeCN)\u2082]\u00b2\u207a system (TON of 149) features a stronger-field, more rigid auxiliary ligand that maintains cis-labile sites and a dominant low-spin population at the Fe(II) state. The latter is posited to mitigate demetalation and hence catalyst degradation by the presence of a large excess of ammonia under the catalytic conditions. Additionally, the [(bpyPy\u2082Me)Fe(MeCN)\u2082]\u00b2\u207a system exhibits a substantially faster AO rate (ca. 50\u00d7) at significantly lower (\u223c250 mV) applied bias compared to [(TPA)Fe(MeCN)\u2082]\u00b2\u207a. Electrochemical data are consistent with an initial E\u2081 net H-atom abstraction step that furnishes the cis amide/ammine complex [(bpyPy\u2082Me)Fe(NH\u2082)(NH\u2083)]\u00b2\u207a, followed by the onset of catalysis at E\u2082. Theoretical calculations suggest the possibility of N\u2013N bond formation via multiple thermodynamically plausible pathways, including both reductive elimination and ammonia nucleophilic attack. In sum, this study underscores that Fe, an earth-abundant metal, is a promising metal for further development in metal-mediated AO catalysis by molecular systems.", "date": "2021-05-26", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "20", "publisher": "American Chemical Society", "pagerange": "7612-7616", "id_number": "CaltechAUTHORS:20210518-100146952", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210518-100146952", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM070757" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.1c02232", "pmcid": "PMC8238494", "primary_object": { "basename": "ja1c02232_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mdzkc-wzn51/files/ja1c02232_si_001.pdf" }, "related_objects": [ { "basename": "nihms-1716691.pdf", "url": "https://authors.library.caltech.edu/records/mdzkc-wzn51/files/nihms-1716691.pdf" } ], "pub_year": "2021", "author_list": "Zott, Michael D. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/pdx78-8ax02", "eprint_id": 109188, "eprint_status": "archive", "datestamp": "2023-08-20 03:20:52", "lastmod": "2025-10-24 22:38:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Gen-K", "name": { "family": "Li", "given": "Gen K." }, "orcid": "0000-0002-6300-3570" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "Woodward W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" }, { "id": "West-A-Joshua", "name": { "family": "West", "given": "A. Joshua" }, "orcid": "0000-0001-6909-1471" }, { "id": "Zhang-Ting", "name": { "family": "Zhang", "given": "Ting" } }, { "id": "Galy-Valier", "name": { "family": "Galy", "given": "Valier" }, "orcid": "0000-0003-0385-8443" }, { "id": "Wang-Xingchen-Tony", "name": { "family": "Wang", "given": "Xingchen Tony" }, "orcid": "0000-0001-5316-789X" }, { "id": "Li-Shilei", "name": { "family": "Li", "given": "Shilei" }, "orcid": "0000-0001-7053-2828" }, { "id": "Qiu-Hongrui", "name": { "family": "Qiu", "given": "Hongrui" }, "orcid": "0000-0002-4219-0039" }, { "id": "Li-Gaojun", "name": { "family": "Li", "given": "Gaojun" }, "orcid": "0000-0002-2463-0774" }, { "id": "Zhao-Liang", "name": { "family": "Zhao", "given": "Liang" } }, { "id": "Chen-Jun", "name": { "family": "Chen", "given": "Jun" }, "orcid": "0000-0002-3480-5961" }, { "id": "Ji-Junfeng", "name": { "family": "Ji", "given": "Junfeng" } } ] }, "title": "Coal fly ash is a major carbon flux in the Chang Jiang (Yangtze River) basin", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 Published under the PNAS license. \n\nEdited by Donald E. Canfield, University of Southern Denmark, Odense M., Denmark, and approved March 25, 2021 (received for review December 9, 2019) \n\nThis project was funded by the National Key R&D Program of China (Grant 2017YFD0800300). G.K.L. acknowledges support from a California Institute of Technology Geology Option Postdoctoral Fellowship and a National Ocean Sciences Accelerator Mass Spectrometry Laboratory Graduate Intern Fellowship. W.W.F. and M.P.L. acknowledge support from Foster and Coco Stanback, California Institute of Technology's Terrestrial Hazard Observation and Reporting Center, and the Resnick Sustainability Institute. We thank Yuliang Chen for help with data compilation. \n\nData Availability. All study data are included in the article and/or supporting information. \n\nAuthor contributions: G.K.L., W.W.F., M.P.L., A.J.W., J.C., and J.J. designed research; G.K.L., T.Z., X.T.W., and S.L. performed research; G.K.L., T.Z., V.G., and J.J. contributed new reagents/analytic tools; G.K.L., W.W.F., M.P.L., V.G., X.T.W., S.L., H.Q., G.L., L.Z., and J.J. analyzed data; and G.K.L., W.W.F., M.P.L., A.J.W., T.Z., V.G., X.T.W., S.L., G.L., L.Z., J.C., and J.J. wrote the paper. \n\nThe authors declare no competing interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.1921544118/-/DCSupplemental.\n\n

Published - e1921544118.full.pdf

Supplemental Material - pnas.1921544118.sapp.pdf

Supplemental Material - pnas.1921544118.sd01.xlsx

", "abstract": "Fly ash\u2014the residuum of coal burning\u2014contains a considerable amount of fossilized particulate organic carbon (FOC_(ash)) that remains after high-temperature combustion. Fly ash leaks into natural environments and participates in the contemporary carbon cycle, but its reactivity and flux remained poorly understood. We characterized FOC_(ash) in the Chang Jiang (Yangtze River) basin, China, and quantified the riverine FOC_(ash) fluxes. Using Raman spectral analysis, ramped pyrolysis oxidation, and chemical oxidation, we found that FOC_(ash) is highly recalcitrant and unreactive, whereas shale-derived FOC (FOC_(rock)) was much more labile and easily oxidized. By combining mass balance calculations and other estimates of fly ash input to rivers, we estimated that the flux of FOCash carried by the Chang Jiang was 0.21 to 0.42 Mt C\u22c5y\u207b\u00b9 in 2007 to 2008\u2014an amount equivalent to 37 to 72% of the total riverine FOC export. We attributed such high flux to the combination of increasing coal combustion that enhances FOCash production and the massive construction of dams in the basin that reduces the flux of FOC_(rock) eroded from upstream mountainous areas. Using global ash data, a first-order estimate suggests that FOC_(ash) makes up to 16% of the present-day global riverine FOC flux to the oceans. This reflects a substantial impact of anthropogenic activities on the fluxes and burial of fossil organic carbon that has been made less reactive than the rocks from which it was derived.", "date": "2021-05-25", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "118", "number": "21", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e1921544118", "id_number": "CaltechAUTHORS:20210519-141319478", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210519-141319478", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFD0800300" }, { "agency": "Foster and Coco Stanback" }, { "agency": "Terrestrial Hazard Observation and Reporting Center" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.1921544118", "pmcid": "PMC8166106", "primary_object": { "basename": "e1921544118.full.pdf", "url": "https://authors.library.caltech.edu/records/pdx78-8ax02/files/e1921544118.full.pdf" }, "related_objects": [ { "basename": "pnas.1921544118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/pdx78-8ax02/files/pnas.1921544118.sapp.pdf" }, { "basename": "pnas.1921544118.sd01.xlsx", "url": "https://authors.library.caltech.edu/records/pdx78-8ax02/files/pnas.1921544118.sd01.xlsx" } ], "pub_year": "2021", "author_list": "Li, Gen K.; Fischer, Woodward W.; et al." }, { "id": "https://authors.library.caltech.edu/records/cfvz2-bqj12", "eprint_id": 109133, "eprint_status": "archive", "datestamp": "2023-08-22 09:52:13", "lastmod": "2025-04-23 19:31:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shi-Ye", "name": { "family": "Shi", "given": "Ye" }, "orcid": "0000-0002-5228-1604" }, { "id": "Ilic-Ognjen", "name": { "family": "Ilic", "given": "Ognjen" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "All-day fresh water harvesting by microstructured hydrogel membranes", "ispublished": "pub", "full_text_status": "public", "keywords": "Devices for energy harvesting; Gels and hydrogels; Polymers", "note": "\u00a9 The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 04 February 2021; Accepted 15 April 2021; Published 14 May 2021. \n\nWe thank Dr. Bruce S. Brunschwig for help with the solar simulator and Daryl Yee for help with 3D printing. We thank Shu Yan for help with drawing schemes. J.R.G. acknowledges the financial support of the Resnick Sustainability Institute and of the Caltech Space Solar Power Project. H.A.A. acknowledges financial support from the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. O. I. acknowledges support from the Caltech Space Solar Power Project and the 3M foundation. \n\nData availability: The data that support the findings of this study are available from the corresponding authors upon request. \n\nAuthor Contributions: Y.S. and J.R.G. conceived the idea. Y.S. performed materials fabrication and characterization. O.I. performed the numerical simulations. Y.S., O.I., H.A.A., and J.R.G. analyzed the data, discussed the results, and wrote the manuscript. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Guihua Yu and Jia Zhu for their contribution to the peer review of this work. Peer reviewer reports are available.\n\n

Published - s41467-021-23174-0.pdf

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Supplemental Material - 41467_2021_23174_MOESM3_ESM.pdf

Supplemental Material - 41467_2021_23174_MOESM4_ESM.mp4

", "abstract": "Solar steam water purification and fog collection are two independent processes that could enable abundant fresh water generation. We developed a hydrogel membrane that contains hierarchical three-dimensional microstructures with high surface area that combines both functions and serves as an all-day fresh water harvester. At night, the hydrogel membrane efficiently captures fog droplets and directionally transports them to a storage vessel. During the daytime, it acts as an interfacial solar steam generator and achieves a high evaporation rate of 3.64\u2009kg\u2009m\u207b\u00b2 h\u207b\u00b9 under 1 sun enabled by improved thermal/vapor flow management. With a homemade rooftop water harvesting system, this hydrogel membrane can produce fresh water with a daily yield of ~34\u2009L\u2009m\u207b\u00b2 in an outdoor test, which demonstrates its potential for global water scarcity relief.", "date": "2021-05-14", "date_type": "published", "publication": "Nature Communications", "volume": "12", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2797", "id_number": "CaltechAUTHORS:20210514-114309275", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210514-114309275", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Space Solar Power Project" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "3M Foundation" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Space-Solar-Power-Project" } ] }, "doi": "10.1038/s41467-021-23174-0", "pmcid": "PMC8121874", "primary_object": { "basename": "41467_2021_23174_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2021_23174_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM2_ESM.pdf" }, { "basename": "41467_2021_23174_MOESM3_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM3_ESM.pdf" }, { "basename": "41467_2021_23174_MOESM4_ESM.mp4", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM4_ESM.mp4" }, { "basename": "s41467-021-23174-0.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/s41467-021-23174-0.pdf" } ], "pub_year": "2021", "author_list": "Shi, Ye; Ilic, Ognjen; et al." }, { "id": "https://authors.library.caltech.edu/records/eamm1-9a070", "eprint_id": 108900, "eprint_status": "archive", "datestamp": "2023-08-20 03:11:16", "lastmod": "2023-10-23 17:24:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Simonoff-Ethan", "name": { "family": "Simonoff", "given": "Ethan" }, "orcid": "0000-0002-2156-8602" }, { "id": "Thompson-Jonathan-R", "name": { "family": "Thompson", "given": "Jonathan R." } }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Kennedy-Kathleen-M", "name": { "family": "Kennedy", "given": "Kathleen M." }, "orcid": "0000-0002-7125-4871" }, { "id": "Hamann-Kathryn-R", "name": { "family": "Hamann", "given": "Kathryn R." }, "orcid": "0000-0003-1163-7173" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Preseeded Optical Scatterers as a Template for Enhancing Order in Inorganic Phototropic Growth", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: April 5, 2021; Revised: April 8, 2021; Published: April 22, 2021. \n\nThis work was supported by the National Science Foundation under Award Number DMR1905963. M.C.M. and K.R.H. acknowledge Graduate Research Fellowships from the National Science Foundation. M.C.M. also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nAuthor Contributions: E.S. and J.R.T. contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - jp1c02746_si_001.pdf

", "abstract": "Lithographically patterned substrates were used as templates of optical scatterers that seeded the inorganic phototropic growth of Se\u2013Te. Relative to films grown on nominally featureless substrates, films grown on substrates having patterned optical scatterers demonstrated much improved Se\u2013Te pattern fidelities and a narrower distribution of film pattern spatial periods, as quantified by Fourier spectrum analysis. Full-wave electromagnetic modeling and Monte Carlo simulations of Se\u2013Te film growth on substrates with patterned optical scatterers were in good agreement with the patterns observed experimentally. Additional simulations were performed to investigate the limits to pattern period confinement. Simulations revealed that films deposited onto templated substrates can exhibit pattern periods as low as \u223c80% and as high as \u223c160% of the pattern period observed for films deposited on nontemplated substrates.", "date": "2021-05-06", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "125", "number": "17", "publisher": "American Chemical Society", "pagerange": "9571-9581", "id_number": "CaltechAUTHORS:20210430-103304262", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210430-103304262", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1905963" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.1c02746", "primary_object": { "basename": "jp1c02746_si_001.pdf", "url": "https://authors.library.caltech.edu/records/eamm1-9a070/files/jp1c02746_si_001.pdf" }, "pub_year": "2021", "author_list": "Simonoff, Ethan; Thompson, Jonathan R.; et al." }, { "id": "https://authors.library.caltech.edu/records/s59v2-xbn10", "eprint_id": 107438, "eprint_status": "archive", "datestamp": "2023-08-22 09:41:01", "lastmod": "2025-04-23 19:55:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Phelan-Megan-E", "name": { "family": "Phelan", "given": "Megan" }, "orcid": "0000-0002-4968-7128" }, { "id": "Needell-David-R", "name": { "family": "Needell", "given": "David R." }, "orcid": "0000-0001-8343-5883" }, { "id": "Bauser-Haley-C", "name": { "family": "Bauser", "given": "Haley" }, "orcid": "0000-0002-9677-3301" }, { "id": "Su-Hanxiao", "name": { "family": "Su", "given": "Hanxiao" }, "orcid": "0000-0001-7247-7869" }, { "id": "Deceglie-Michael", "name": { "family": "Deceglie", "given": "Michael" }, "orcid": "0000-0001-7063-9676" }, { "id": "Theingi-San", "name": { "family": "Theingi", "given": "San" } }, { "id": "Koscher-Brent", "name": { "family": "Koscher", "given": "Brent" }, "orcid": "0000-0001-8233-0852" }, { "id": "Nett-Zachary", "name": { "family": "Nett", "given": "Zach" }, "orcid": "0000-0002-8086-4380" }, { "id": "Bukowsky-Colton-R", "name": { "family": "Bukowsky", "given": "Colton R." }, "orcid": "0000-0003-3577-8050" }, { "id": "Ilic-Ognjen", "name": { "family": "Ilic", "given": "Ognjen" } }, { "id": "Stradins-Paul", "name": { "family": "Stradins", "given": "Paul" } }, { "id": "Geisz-John-F", "name": { "family": "Geisz", "given": "John" }, "orcid": "0000-0003-4818-653X" }, { "id": "Nuzzo-Ralph-G", "name": { "family": "Nuzzo", "given": "Ralph" }, "orcid": "0000-0003-2310-2045" }, { "id": "Alivisatos-A-Paul", "name": { "family": "Alivisatos", "given": "A. Paul" }, "orcid": "0000-0001-6895-9048" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Outdoor performance of a tandem InGaP/Si photovoltaic luminescent solar concentrator", "ispublished": "pub", "full_text_status": "public", "keywords": "Luminescent solar concentrator; Tandem photovoltaic; Quantum dot; Microcell; Outdoor testing", "note": "\u00a9 2021 Elsevier. \n\nReceived 22 October 2020, Revised 19 December 2020, Accepted 22 December 2020, Available online 10 January 2021. \n\nThis work was supported in part by the Advanced Research Projects Agency for Energy (ARPA-E, U.S. Department of Energy Micro-scale Optimized Solar-cell Arrays with Integrated Circuits (MOSAIC) Award DE-AR0000627, and in part by the Engineering Research Center Program of the National Science Foundation and the Office of Energy Efficiency and Renewable Energy of the Department of Energy under NSF Cooperative Agreement No. EEC-1041895. The authors thank Joshua Morse for his expertise in the outdoor testing facility setup, Waldo Olavarria for OMVPE growth of GaInP cells, and the Resnick Institute for Sustainability at the California Institute of Technology for their continued support. This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding was provided by ARPA-E. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. \n\nCRediT authorship contribution statement. Megan Phelan: Conceptualization, Methodology, Data collection, Writing - original draft. David R. Needell: Conceptualization, Methodology, Data collection, Writing - original draft. Haley Bauser: Conceptualization, Methodology, Data collection, Writing - review & editing. Hanxiao Su: Methodology, Data collection. Michael Deceglie: Data collection. San Theingi: Methodology, Data collection. Brent Koscher: Methodology, Data collection. Zach Nett: Methodology, Data collection. Colton R. Bukowsky: Data collection. Ognjen Ilic: Methodology, Data collection. Paul Stradins: Conceptualization, Methodology. John Geisz: Conceptualization, Methodology, Data collection. Ralph Nuzzo: Conceptualization, Methodology. A. Paul Alivisatos: Conceptualization, Methodology. Harry A. Atwater: Conceptualization, Methodology, Writing - review & editing. \n\nThe authors declare that they have no competing interests with respect to this manuscript.\n\n

Supplemental Material - 1-s2.0-S0927024820305407-mmc1.docx

", "abstract": "We report the design, fabrication and outdoor characterization of a tandem luminescent solar concentrator/Si multi-junction photovoltaic module. Our tandem LSC/Si device consists of an InGaP LSC functioning as a top cell and a passivated contact Si bottom cell. The LSC comprises of an InGaP microcell array coupled to a polymer waveguide, loaded with CdSe/CdS core-shell quantum dot luminophores. The light trapping efficiency of the LSC waveguide is enhanced by encapsulation with photoluminescence trapping mirrors consisting of dielectric multilayer thin films. We demonstrate the performance of the LSC/Si device through a series of outdoor tests under various irradiance conditions conducted at the National Renewable Energy Laboratory. We report the first outdoor testing data of an LSC/Si tandem module, displaying maintained performance across varied diffusivity conditions for the LSC component. Finally, we model the tandem module performance using a ray optic simulation-based multiphysics model and forecast a pathway for high efficiency tandem LSC/Si module performance.", "date": "2021-05", "date_type": "published", "publication": "Solar Energy Materials and Solar Cells", "volume": "223", "publisher": "Elsevier", "pagerange": "Art. No. 110945", "id_number": "CaltechAUTHORS:20210112-135210241", "issn": "0927-0248", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210112-135210241", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "ARPA-E", "grant_number": "DE-AR0000627" }, { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.solmat.2020.110945", "primary_object": { "basename": "1-s2.0-S0927024820305407-mmc1.docx", "url": "https://authors.library.caltech.edu/records/s59v2-xbn10/files/1-s2.0-S0927024820305407-mmc1.docx" }, "pub_year": "2021", "author_list": "Phelan, Megan; Needell, David R.; et al." }, { "id": "https://authors.library.caltech.edu/records/726pw-pv947", "eprint_id": 108796, "eprint_status": "archive", "datestamp": "2023-08-20 02:50:39", "lastmod": "2025-05-06 19:39:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johnson-Samantha-I", "name": { "family": "Johnson", "given": "Samantha I." }, "orcid": "0000-0001-6495-9892" }, { "id": "Blakemore-James-D", "name": { "family": "Blakemore", "given": "James D." }, "orcid": "0000-0003-4172-7460" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William Andrew" }, "orcid": "0000-0003-0097-5716" }, { "id": "Persson-Petter", "name": { "family": "Persson", "given": "Petter" }, "orcid": "0000-0001-7600-3230" } ] }, "title": "Design of robust 2,2\u2032-bipyridine ligand linkers for the stable immobilization of molecular catalysts on silicon(111) surfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 the Owner Societies 2021. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. \n\nSubmitted 05 Feb 2021; Accepted 06 Apr 2021; First published 06 Apr 2021. \n\nResearch at Caltech was supported by the National Science Foundation Center for Chemical Innovation Solar Fuels (NSF CHE-1305124). S. I. J. was supported by a National Science Foundation Graduate Research Fellowship (Grant No. DGE-1144469), a National Science Foundation Graduate Research Opportunities Worldwide Grant, and by the generous support of the Resnick Sustainability Institute. S. I. J. and P. P. were supported by the Swedish Research Council (VR). W. A. G. was partially supported by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. P. P. acknowledges the Swedish Energy Agency (STEM) as well as the Swedish supercomputing facilities LUNARC and NSC for support. S. I. J. thanks Drs. Robert J. Nielsen and Noah Plymale for helpful discussions. S. I. J. and P. P. thank Drs. Lisa A. Fredin and Marta Galynska for helpful discussions. \n\nThere are no conflicts to declare.\n\n

Published - d1cp00545f.pdf

Supplemental Material - d1cp00545f1.pdf

Supplemental Material - d1cp00545f2.xyz

", "abstract": "The attachment of the 2,2\u2032-bipyridine (bpy) moieties to the surface of planar silicon(111) (photo)electrodes was investigated using ab initio simulations performed on a new cluster model for methyl-terminated silicon. Density functional theory (B3LYP) with implicit solvation techniques indicated that adventitious chlorine atoms, when present in the organic linker backbone, led to instability at very negative potentials of the surface-modified electrode. In prior experimental work, chlorine atoms were present as a trace surface impurity due to required surface processing chemistry, and thus could plausibly result in the observed surface instability of the linker. Free energy calculations for the Cl-atom release process with model silyl-linker constructs revealed a modest barrier (14.9 kcal mol\u207b\u00b9) that decreased as the electrode potential became more negative. A small library of new bpy-derived structures has additionally been explored computationally to identify strategies that could minimize chlorine-induced linker instability. Structures with fluorine substituents are predicted to be more stable than their chlorine analogues, whereas fully non-halogenated structures are predicted to exhibit the highest stability. The behavior of a hydrogen-evolving molecular catalyst Cp*Rh(bpy) (Cp* = pentamethylcyclopentadienyl) immobilized on a silicon(111) cluster was explored theoretically to evaluate differences between the homogeneous and surface-attached behavior of this species in a tautomerization reaction observed under reductive conditions for catalytic H\u2082 evolution. The calculated free energy difference between the tautomers is small, hence the results suggest that use of reductively stable linkers can enable robust attachment of catalysts while maintaining chemical behavior on the electrode similar to that exhibited in homogeneous solution.", "date": "2021-04-28", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "23", "number": "16", "publisher": "Royal Society of Chemistry", "pagerange": "9921-9929", "id_number": "CaltechAUTHORS:20210421-170248147", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210421-170248147", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Swedish Research Council" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" } ] }, "other_numbering_system": { "items": [ { "id": "1427", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d1cp00545f", "primary_object": { "basename": "d1cp00545f.pdf", "url": "https://authors.library.caltech.edu/records/726pw-pv947/files/d1cp00545f.pdf" }, "related_objects": [ { "basename": "d1cp00545f1.pdf", "url": "https://authors.library.caltech.edu/records/726pw-pv947/files/d1cp00545f1.pdf" }, { "basename": "d1cp00545f2.xyz", "url": "https://authors.library.caltech.edu/records/726pw-pv947/files/d1cp00545f2.xyz" } ], "pub_year": "2021", "author_list": "Johnson, Samantha I.; Blakemore, James D.; et al." }, { "id": "https://authors.library.caltech.edu/records/0p5xg-31620", "eprint_id": 108586, "eprint_status": "archive", "datestamp": "2023-10-03 22:41:14", "lastmod": "2023-10-24 15:32:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Fontani-Herreros-Alex-M", "name": { "family": "Fontani-Herreros", "given": "Alex M." } }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Dramatic HER Suppression on Ag Electrodes via Molecular Films for Highly Selective CO\u2082 to CO Reduction", "ispublished": "pub", "full_text_status": "public", "keywords": "electrocatalysis, CO\u2082RR, HER, solar fuels, modified electrodes, silver electrodes", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: January 24, 2021; Revised: March 13, 2021; Published: March 29, 2021. \n\nNMR, AFM, and XPS, SEM, and EDX measurements were collected at the NMR Facility (Division of Chemistry and Chemical Engineering), the Molecular Materials Research Center (Beckman Institute), and the Analytic Facilities (Division of Geological and Planetary Sciences) of the California Institute of Technology, respectively. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). J.C.P also acknowledges additional support from the Resnick Sustainability Institute at Caltech.\n\nThe authors declare no competing financial interest.\n\n

Accepted Version - ACS_Catalysis_Ag_additives.pdf

Supplemental Material - cs1c00338_si_001.pdf

", "abstract": "The carbon dioxide reduction reaction (CO\u2082RR) in aqueous electrolytes suffers from efficiency loss due to the competitive hydrogen evolution reaction (HER). Developing efficient methods to suppress HER is a crucial step toward CO\u2082 utilization. Herein we report the selective conversion of CO\u2082 to CO on planar silver electrodes with Faradaic efficiencies >99% using simple pyridinium-based additives. Similar to our previous studies on copper electrodes, the additives form an organic film which alters CO\u2082RR selectivity. We report electrochemical kinetic and other mechanistic data to shed light on the role of these organic layers in suppressing HER. These data suggest that hydrogen production is selectively inhibited by the growth of a hydrophobic organic layer on the silver surface that limits proton but not CO\u2082 mass transport at certain applied potentials. The data also point to the involvement of a proton-transfer within the rate-determining step of the catalysis, instead of the commonly observed electron-transfer step for the case of planar Ag electrodes.", "date": "2021-04-16", "date_type": "published", "publication": "ACS Catalysis", "volume": "11", "number": "8", "publisher": "American Chemical Society", "pagerange": "4530-4537", "id_number": "CaltechAUTHORS:20210330-144253307", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210330-144253307", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscatal.1c00338", "primary_object": { "basename": "ACS_Catalysis_Ag_additives.pdf", "url": "https://authors.library.caltech.edu/records/0p5xg-31620/files/ACS_Catalysis_Ag_additives.pdf" }, "related_objects": [ { "basename": "cs1c00338_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0p5xg-31620/files/cs1c00338_si_001.pdf" } ], "pub_year": "2021", "author_list": "Thevenon, Arnaud; Rosas-Hern\u00e1ndez, Alonso; et al." }, { "id": "https://authors.library.caltech.edu/records/k42dq-dak69", "eprint_id": 108579, "eprint_status": "archive", "datestamp": "2023-10-03 22:40:58", "lastmod": "2025-04-23 15:28:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Digdaya-Ibadillah-A", "name": { "family": "Digdaya", "given": "Ibadillah A." }, "orcid": "0000-0001-7349-0934" }, { "id": "Kent-Ron", "name": { "family": "Kent", "given": "Ron" } }, { "id": "Ghougassian-Paul", "name": { "family": "Ghougassian", "given": "Paul" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Comparative Technoeconomic Analysis of Renewable Generation of Methane Using Sunlight, Water, and Carbon Dioxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: January 25, 2021; Accepted: February 26, 2021; Publication Date: March 26, 2021. \n\nThe authors acknowledge the support from SoCalGas on the cost analysis of hydrogen generation, CO\u2082 and water capture, as well as thermochemical and biochemical methanation processes. The cost analysis on electrochemical and photoelectrochemical CO\u2082 conversion is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. A.J.W. acknowledges support from the Resnick Sustainability Institute at Caltech for fellowship support and from the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 174530. \n\nAuthor Contributions: A.J.W. and I.A.D. contributed equally to this work. A.J.W, I.A.D., R.K., P.G., C.X., and H.A.A. conceived the idea and examined the feasibility of such a process. A.J.W. and I.A.D. performed all of the calculations and research required to complete the energy analysis of various systems. R.K., P.G., C.X., and H.A.A advised throughout the process and provided valuable input for determining the viability of various proposed processes. A.J.W., I.A.D., C.X., and H.A.A. wrote the paper, and all authors commented on the manuscript. \n\nViews expressed in this Energy Focus are those of the authors and not necessarily the views of the ACS. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nz1c00174_si_001.zip

Supplemental Material - nz1c00174_si_002.pdf

", "abstract": "Thirty-one percent of the primary energy consumed in the United States comes from the burning of natural gas, 70\u201390% of which is composed of methane (CH\u2084). Natural gas is recovered from onshore and offshore natural gas and oil wells and from coal beds. Currently, the United States has enough supply of dry natural gas to sustain current consumption for 92 years. Meanwhile, California consumes 2.14 MMcf (43.2 million tons) of natural gas per year, over a quarter of which is used to generate electric power and which provides approximately 40% of the electrical energy in the state. Because an extensive nationwide storage and distribution network already exists for natural gas, the development of renewable CH\u2084 could enable rapid and widespread distribution of zero-carbon energy services. Thus, for California to meet its renewable portfolio standard, that is, 60% renewable energy for electricity generation by 2030, and to conserve a limited resource, it is imperative to assess how to develop and deploy technologies for renewable generation of CH\u2084 in the next decade.", "date": "2021-04-09", "date_type": "published", "publication": "ACS Energy Letters", "volume": "6", "number": "4", "publisher": "American Chemical Society", "pagerange": "1540-1549", "id_number": "CaltechAUTHORS:20210330-080727558", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210330-080727558", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-174530" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.1c00174", "primary_object": { "basename": "nz1c00174_si_001.zip", "url": "https://authors.library.caltech.edu/records/k42dq-dak69/files/nz1c00174_si_001.zip" }, "related_objects": [ { "basename": "nz1c00174_si_002.pdf", "url": "https://authors.library.caltech.edu/records/k42dq-dak69/files/nz1c00174_si_002.pdf" } ], "pub_year": "2021", "author_list": "Welch, Alex J.; Digdaya, Ibadillah A.; et al." }, { "id": "https://authors.library.caltech.edu/records/yvtff-sc311", "eprint_id": 106604, "eprint_status": "archive", "datestamp": "2023-08-20 02:37:44", "lastmod": "2025-11-18 22:11:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Teh-Ying-Shi", "name": { "family": "Teh", "given": "Ying Shi" }, "orcid": "0000-0003-1743-4158" }, { "id": "Li-Jiangyu", "name": { "family": "Li", "given": "Jiangyu" }, "orcid": "0000-0003-0533-1397" }, { "id": "Bhattacharya-K", "name": { "family": "Bhattacharya", "given": "Kaushik" }, "orcid": "0000-0003-2908-5469" } ] }, "title": "Understanding the morphotropic phase boundary of perovskite solid solutions as a frustrated state", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Physical Society. \n\nReceived 18 December 2020; revised 7 March 2021; accepted 23 March 2021; published 5 April 2021. \n\nY.S.T. and K.B. gratefully acknowledge useful discussions with R. Bai, as well as the support of the De Logi Foundation through a gift to the California Institute of Technology (Caltech). Y.S.T. further acknowledges the support of Resnick Institute at Caltech through the Resnick Graduate Research Fellowship.\n\n

Published - PhysRevB.103.144201.pdf

Submitted - 2011.00752.pdf

Supplemental Material - Movie_M1.avi

Supplemental Material - SI.pdf

", "abstract": "This paper presents a lattice model incorporating random fields and long-range interactions where a frustrated state emerges at a specific composition but is suppressed elsewhere. The model is motivated by perovskite solid solutions and explains the phase diagram in such materials including the morphotropic phase boundary (MPB) that plays a critical role in applications for its enhanced dielectric, piezoelectric, and optical properties. Further, the model also suggests the possibility of phenomena by exploiting MPBs.", "date": "2021-04-01", "date_type": "published", "publication": "Physical Review B", "volume": "103", "number": "14", "publisher": "American Physical Society", "pagerange": "Art. No. 144201", "id_number": "CaltechAUTHORS:20201111-074328723", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201111-074328723", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech De Logi Fund" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.103.144201", "primary_object": { "basename": "2011.00752.pdf", "url": "https://authors.library.caltech.edu/records/yvtff-sc311/files/2011.00752.pdf" }, "related_objects": [ { "basename": "Movie_M1.avi", "url": "https://authors.library.caltech.edu/records/yvtff-sc311/files/Movie_M1.avi" }, { "basename": "PhysRevB.103.144201.pdf", "url": "https://authors.library.caltech.edu/records/yvtff-sc311/files/PhysRevB.103.144201.pdf" }, { "basename": "SI.pdf", "url": "https://authors.library.caltech.edu/records/yvtff-sc311/files/SI.pdf" } ], "pub_year": "2021", "author_list": "Teh, Ying Shi; Li, Jiangyu; et al." }, { "id": "https://authors.library.caltech.edu/records/9p6q0-1bx26", "eprint_id": 103582, "eprint_status": "archive", "datestamp": "2023-08-22 09:22:19", "lastmod": "2023-10-20 16:31:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Suh-Myoung-Gyun", "name": { "family": "Suh", "given": "Myoung-Gyun" }, "orcid": "0000-0002-9527-0585" }, { "id": "Shen-Boqiang", "name": { "family": "Shen", "given": "Boqiang" }, "orcid": "0000-0003-0697-508X" }, { "id": "\u015eafak-Kemal", "name": { "family": "\u015eafak", "given": "Kemal" } }, { "id": "Dai-Anan", "name": { "family": "Dai", "given": "Anan" } }, { "id": "Wang-Heming", "name": { "family": "Wang", "given": "Heming" }, "orcid": "0000-0003-3861-0624" }, { "id": "Wu-Lue", "name": { "family": "Wu", "given": "Lue" }, "orcid": "0000-0002-7503-7057" }, { "id": "Yuan-Zhiquan", "name": { "family": "Yuan", "given": "Zhiquan" } }, { "id": "Yang-Qi-Fan", "name": { "family": "Yang", "given": "Qi-Fan" }, "orcid": "0000-0002-7036-1712" }, { "id": "Matsko-Andrey-B", "name": { "family": "Matsko", "given": "Andrey B." }, "orcid": "0000-0001-9939-9311" }, { "id": "K\u00e4rtner-Franz-X", "name": { "family": "K\u00e4rtner", "given": "Franz X." } }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry J." }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Quantum diffusion of microcavity solitons", "ispublished": "pub", "full_text_status": "public", "keywords": "Frequency combs; Nonlinear optics; Solitons", "note": "\u00a9 2020 Nature Publishing Group. \n\nReceived 20 March 2020; Accepted 11 November 2020; Published 25 January 2021.\n\nThis work is supported by the Air Force Office of Scientific Research (FA9550-18-1-0353) and the Kavli Institute of Nanoscience. C.B. acknowledges a postdoctoral fellowship from the Resnick Institute at Caltech. The work of A.B.M. was carried out at the JPL, Caltech, under a contract with the National Aeronautics and Space Administration. \n\nData availability: The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. \n\nCode availability: The codes used for this study are available from the corresponding author upon reasonable request. \n\nAuthor Contributions: C.B., K.\u015e., A.B.M., F.X.K. and K.J.V. conceived the project. C.B. ran the experiments with assistance from B.S., Z.Y. and Q.-F.Y. M.-G.S., H.W. and L.W. prepared the samples. K.\u015e., A.D. and F.X.K. built the BOC. The project was supervised by K.J.V. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Physics thanks Giovanna Tissoni and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\n

Submitted - 2003.06685.pdf

Supplemental Material - 41567_2020_1152_MOESM1_ESM.pdf

", "abstract": "Coherently pumped (Kerr) solitons in an ideal optical microcavity are expected to undergo random quantum motion that determines fundamental performance limits in applications of the soliton microcombs. Here this random walk and its impact on Kerr soliton timing jitter are studied experimentally. The quantum limit is discerned by measuring the relative position of counter-propagating solitons. Their relative motion features weak interactions and also presents common-mode suppression of technical noise, which typically hides the quantum fluctuations. This is in contrast to co-propagating solitons, which are found to have relative timing jitter well below the quantum limit of a single soliton on account of strong correlation of their mutual motion. Good agreement is found between theory and experiment. The results establish the fundamental limits to timing jitter in soliton microcombs and provide new insights on multisoliton physics.", "date": "2021-04", "date_type": "published", "publication": "Nature Physics", "volume": "17", "number": "4", "publisher": "Nature Publishing Group", "pagerange": "462-466", "id_number": "CaltechAUTHORS:20200601-095501587", "issn": "1745-2473", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200601-095501587", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0353" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41567-020-01152-5", "primary_object": { "basename": "41567_2020_1152_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/9p6q0-1bx26/files/41567_2020_1152_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "2003.06685.pdf", "url": "https://authors.library.caltech.edu/records/9p6q0-1bx26/files/2003.06685.pdf" } ], "pub_year": "2021", "author_list": "Bao, Chengying; Suh, Myoung-Gyun; et al." }, { "id": "https://authors.library.caltech.edu/records/jp1kp-wp090", "eprint_id": 108259, "eprint_status": "archive", "datestamp": "2023-08-20 02:31:10", "lastmod": "2023-10-23 16:34:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Martinolich-Andrew-J", "name": { "family": "Martinolich", "given": "Andrew J." }, "orcid": "0000-0002-7866-9594" }, { "id": "Ware-Skyler-D", "name": { "family": "Ware", "given": "Skyler D." }, "orcid": "0000-0002-3249-1946" }, { "id": "Lee-Brian-C", "name": { "family": "Lee", "given": "Brian C." } }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "From Solid Electrolyte to Zinc Cathode: Vanadium Substitution in ZnPS\u2083", "ispublished": "pub", "full_text_status": "public", "keywords": "zinc battery, zinc cathode, multivalent ionics, multivalent battery", "note": "\u00a9 2021 The Author(s). Published by IOP Publishing Ltd.\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 20 December 2020; Accepted 4 February 2021; Published 25 February 2021. \n\nThis research was supported by the Arnold and Mabel Beckman Foundation through the Beckman Young Investigator Award. The authors thank Dr FAL Laskowski for many enlightening discussions. AJM was partially supported through a postdoctoral fellowship from the Resnick Sustainability Institute at Caltech. XPS data were collected at the Molecular Materials Research Center in the Beckman Institute at Caltech.\n\n

Published - Martinolich_2021_J._Phys._Mater._4_024005.pdf

", "abstract": "Development of next generation batteries is predicated on the design and discovery of new, functional materials. Divalent cations are promising options that go beyond the canonical Li-based systems, but the development of new materials for divalent ion batteries is hindered due to difficulties in promoting divalent ion conduction. We have developed a family of cathode materials based on the divalent cation conductor ZnPS\u2083. Substitution of V for Zn in the lattice concomitant with vacancy introduction yields isostructural but redox-active materials that can reversibly store Zn\u00b2\u207a in the vacancies. A range of voltammetry and galvanostatic cycling experiments along with x-ray photoelectron spectroscopy support that redox is indeed centered on V and that capacity is dependent on the V content. The voltage of the materials is limited by the irreversible decomposition of the [P\u2082S\u2086]\u2074\u207b polyanion above 1.4 V vs. Zn/Zn\u00b2\u207a. The reversible capacity before anion decomposition is limited to half the vacancies and is due to the relative ratios of oxidized and reduced V centers. Such observations provide useful design rules for cathode materials for divalent cation based battery technologies, and highlight the necessity for a holistic interpretation of physical and electronic structural changes upon cycling.", "date": "2021-04", "date_type": "published", "publication": "Journal of Physics: Materials", "volume": "4", "number": "2", "publisher": "IOP Publishing", "pagerange": "Art. No. 024005", "id_number": "CaltechAUTHORS:20210301-154055511", "issn": "2515-7639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210301-154055511", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1088/2515-7639/abe365", "primary_object": { "basename": "Martinolich_2021_J._Phys._Mater._4_024005.pdf", "url": "https://authors.library.caltech.edu/records/jp1kp-wp090/files/Martinolich_2021_J._Phys._Mater._4_024005.pdf" }, "pub_year": "2021", "author_list": "Martinolich, Andrew J.; Ware, Skyler D.; et al." }, { "id": "https://authors.library.caltech.edu/records/3fd4t-eec63", "eprint_id": 105784, "eprint_status": "archive", "datestamp": "2023-08-20 02:28:16", "lastmod": "2023-10-20 22:25:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tong-Xiao", "name": { "family": "Tong", "given": "Xiao" } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Toward precise simulations of the coupled ultrafast dynamics of electrons and atomic vibrations in materials", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. \n\nReceived 13 October 2020; accepted 6 April 2021; published 26 April 2021. \n\nThe authors thank Jin-Jian Zhou for fruitful discussions. X.T. thanks the Resnick Sustainability Institute at the California Institute of Technology for fellowship support. This work was partially supported by the National Science Foundation under Grant No. DMR-1750613, which provided for theory development, and by the Department of Energy under Grant No. DE-SC0019166, which provided for numerical calculations and code development. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a US Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231.\n\n

Published - PhysRevResearch.3.023072.pdf

Submitted - 2009.07958.pdf

Supplemental Material - S1.mov

Supplemental Material - Supplemental-Material.pdf

", "abstract": "Ultrafast spectroscopies can access the dynamics of electrons and nuclei at short timescales, shedding light on nonequilibrium phenomena in materials. However, development of accurate calculations to interpret these experiments has lagged behind as widely adopted simulation schemes are limited to subpicosecond timescales or employ simplified interactions lacking quantitative accuracy. Here we show a precise approach to obtain the time-dependent populations of nonequilibrium electrons and atomic vibrations (phonons) up to tens of picoseconds, with a femtosecond time resolution. Combining first-principles electron-phonon and phonon-phonon interactions with a parallel numerical scheme to time-step the coupled electron and phonon Boltzmann equations, our method provides microscopic insight into scattering mechanisms in excited materials. Focusing on graphene as a case study, we demonstrate calculations of ultrafast electron and phonon dynamics, transient optical absorption, structural snapshots, and diffuse x-ray scattering. Our first-principles approach paves the way for quantitative atomistic simulations of ultrafast dynamics in materials.", "date": "2021-04", "date_type": "published", "publication": "Physical Review Research", "volume": "3", "number": "2", "publisher": "American Physical Society", "pagerange": "Art. No. 023072", "id_number": "CaltechAUTHORS:20201005-102911333", "issn": "2643-1564", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201005-102911333", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevResearch.3.023072", "primary_object": { "basename": "Supplemental-Material.pdf", "url": "https://authors.library.caltech.edu/records/3fd4t-eec63/files/Supplemental-Material.pdf" }, "related_objects": [ { "basename": "2009.07958.pdf", "url": "https://authors.library.caltech.edu/records/3fd4t-eec63/files/2009.07958.pdf" }, { "basename": "PhysRevResearch.3.023072.pdf", "url": "https://authors.library.caltech.edu/records/3fd4t-eec63/files/PhysRevResearch.3.023072.pdf" }, { "basename": "S1.mov", "url": "https://authors.library.caltech.edu/records/3fd4t-eec63/files/S1.mov" } ], "pub_year": "2021", "author_list": "Tong, Xiao and Bernardi, Marco" }, { "id": "https://authors.library.caltech.edu/records/sy8kc-v7d12", "eprint_id": 108391, "eprint_status": "archive", "datestamp": "2023-08-20 02:21:16", "lastmod": "2025-11-19 00:22:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Kennedy-Kathleen-M", "name": { "family": "Kennedy", "given": "Kathleen M." }, "orcid": "0000-0002-7125-4871" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Hamann-Kathryn-R", "name": { "family": "Hamann", "given": "Kathryn R." }, "orcid": "0000-0003-1163-7173" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Assessing Effects of Near-Field Synergistic Light Absorption on Ordered Inorganic Phototropic Growth", "ispublished": "pub", "full_text_status": "public", "keywords": "Morphology, Light absorption, Absorption, Toxicological synergy, Deposition", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: December 18, 2020;\nPublished: March 8, 2021.\n\nThis work was supported by the National Science Foundation, Directorate for Mathematical & Physical Sciences, Division of Materials Research under Award Number DMR 1905963. The authors gratefully acknowledge J. R. Thompson and W.-H. Cheng for insightful discussions and R. Gerhart and N. Hart for assistance with photoelectrochemical cell fabrication. M.C.M. and K.R.H. acknowledge Graduate Research Fellowships from the National Science Foundation. M.C.M. also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nAuthor Contributions: A.I.C. and M.C.M. contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja0c13085_si_001.pdf

", "abstract": "We report herein that synergistic light absorption in the optical near-field enables nanoscale self-organization during inorganic phototropic growth. Se\u2013Te was grown electrochemically under illumination from an incoherent, unstructured light source in geometrically constrained, wavelength scale areas. Despite the limited dimensions, with as few as two discrete features produced in a single sub-micron dimension, the deposit morphology exhibited defined order and anisotropy. Computer modeling analysis of light absorption in simulated structures revealed a synergy wherein light capture in a nanoscale feature was enhanced by the presence of additional adjacent features, with the synergistic effect originating predominantly from nearest neighbor contributions. Modeling moreover indicated that synergistic absorption is produced by scattering of the incident illumination by individual nanoscale features, leading to a local increase in the near-field intensity and consequently increasing the absorption in neighboring features. The interplay between these optical processes establishes the basis for spontaneous order generation via inorganic phototropic growth.", "date": "2021-03-17", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "10", "publisher": "American Chemical Society", "pagerange": "3693-3696", "id_number": "CaltechAUTHORS:20210311-085247183", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210311-085247183", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1905963" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.0c13085", "primary_object": { "basename": "ja0c13085_si_001.pdf", "url": "https://authors.library.caltech.edu/records/sy8kc-v7d12/files/ja0c13085_si_001.pdf" }, "pub_year": "2021", "author_list": "Carim, Azhar I.; Meier, Madeline C.; et al." }, { "id": "https://authors.library.caltech.edu/records/jpz1d-m4m65", "eprint_id": 108087, "eprint_status": "archive", "datestamp": "2023-08-20 02:08:35", "lastmod": "2023-10-23 16:27:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Finke-Cody-E", "name": { "family": "Finke", "given": "Cody E." }, "orcid": "0000-0002-1343-1737" }, { "id": "Leandri-Hugo-F", "name": { "family": "Leandri", "given": "Hugo F." } }, { "id": "Karumb-Evody-Tshijik", "name": { "family": "Karumb", "given": "Evody Tshijik" } }, { "id": "Zheng-David", "name": { "family": "Zheng", "given": "David" } }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" }, { "id": "Fromer-Neil-A", "name": { "family": "Fromer", "given": "Neil A." } } ] }, "title": "Economically advantageous pathways for reducing greenhouse gas emissions from industrial hydrogen under common, current economic conditions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 The Royal Society of Chemistry. \n\nSubmitted 01 Dec 2020; Accepted 03 Feb 2021; First published 15 Feb 2021.\n\nSupporting data referenced above may be found in the ESI. This work was supported by the Department of Energy's Advanced Manufacturing Office Cyclotron Road Program. Funding was provided to C. E. F., H. F. L., and N. A. F., by the Resnick Sustainability Institute at Caltech. In part, this material is based upon work by C. E. F., E. T. K. and H. F. L. performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. C. E. F. was the primary concept generator and modeler for this work. H. F. L. performed the electrochemistry. D. Z. developed early versions of the model. N. A. F. aided in idea development. C. E. F., H. F. L., E. T. K., M. R. H., and N. A. F. prepared the manuscript and helped with its reviewing. All authors reviewed and contributed to the final manuscript. We are grateful to Fanfei Li for helping acquire techno-economic data and Prof. Jess Adkins at Caltech for being willing to relentlessly talk shop with us. \n\nConflicts of interest: H. F. L., D. Z., M. R. H., and N. A. F.'s institution (California Institute of Technology) has filed a U.S. patent application directly relating to the work described in the paper (patent application no. US20190376191A1, filed on May. 17, 2019). C. E. F., H. L., and E. T. K. are founders or employees of Brimstone Energy Inc., a company which has hydrogen cogeneration in its vision.\n\n

Supplemental Material - d0ee03768k11.pdf

", "abstract": "Hydrogen is a major industrial chemical whose manufacture is responsible for \u223c3% of global carbon dioxide emissions. >95% of hydrogen is made via reforming fossil fuels which typically co-produces hydrogen and waste carbon dioxide. Nearly all other hydrogen is co-produced with other commodity chemicals. Unfortunately, many alternative, clean hydrogen production processes are small-scale because they require major reductions in capital cost or energy prices to be economical enough for industry. Because the climate problem is urgent, and the economics of future energy is uncertain, this paper seeks to expand the options for producing industrial-scale, clean hydrogen under common, present-day economic conditions. First, we build a model to understand the economic and carbon dioxide emissions constraints of sulfur electrolysis which is an emerging process that cogenerates hydrogen and co-salable sulfuric acid and has the potential to produce up to 36% of the world's current hydrogen demand under present-day, average US economic conditions. We also use our model to evaluate water electrolysis, which cogenerates hydrogen and waste oxygen, but is not economical under present-day average US economic conditions. We then propose criteria for identifying clean hydrogen production chemistries. Using these criteria, we find enough reactions to have the combined potential to make over 150% of the world's industrial hydrogen needs under present-day, average US economic conditions while reducing cost and reducing or eliminating CO\u2082 emissions. Given the urgency of the climate problem, we believe that an economic analysis, such as this is crucial to near-term CO\u2082 emissions reductions.", "date": "2021-03-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "14", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "1517-1529", "id_number": "CaltechAUTHORS:20210217-100658347", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210217-100658347", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d0ee03768k", "primary_object": { "basename": "d0ee03768k11.pdf", "url": "https://authors.library.caltech.edu/records/jpz1d-m4m65/files/d0ee03768k11.pdf" }, "pub_year": "2021", "author_list": "Finke, Cody E.; Leandri, Hugo F.; et al." }, { "id": "https://authors.library.caltech.edu/records/djwcn-bh103", "eprint_id": 113694, "eprint_status": "archive", "datestamp": "2023-08-22 09:08:29", "lastmod": "2025-11-18 21:42:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" }, { "id": "Silva-Tallyta-N", "name": { "family": "Silva", "given": "Tallyta N." }, "orcid": "0000-0003-0582-4781" }, { "id": "Jackson-Christopher-T", "name": { "family": "Jackson", "given": "Christopher T." }, "orcid": "0000-0002-7177-1203" }, { "id": "Thomas-Jason-B", "name": { "family": "Thomas", "given": "Jason B." }, "orcid": "0000-0002-7801-9006" }, { "id": "Ehrhardt-David-W", "name": { "family": "Ehrhardt", "given": "David W." } }, { "id": "Rhee-Seung-Y", "name": { "family": "Rhee", "given": "Seung Y." }, "orcid": "0000-0002-7572-4762" }, { "id": "Mortimer-Jenny-C", "name": { "family": "Mortimer", "given": "Jenny C." }, "orcid": "0000-0001-6624-636X" }, { "id": "Landry-Markita-P", "name": { "family": "Landry", "given": "Markita P." }, "orcid": "0000-0002-5832-8522" } ] }, "title": "Nanotechnology to advance CRISPR-Cas genetic engineering of plants", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Electrical and Electronic Engineering; Condensed Matter Physics; General Materials Science; Biomedical Engineering; Atomic and Molecular Physics, and Optics; Bioengineering", "note": "\u00a9 2022 Springer Nature Limited. \n\nReceived 28 August 2020. Accepted 14 January 2021. Published 12 March 2021. Issue Date March 2021. \n\nWe thank W. Dwyer and J. Krupp for helpful discussions. G.S.D. is funded by the Schlumberger Foundation Faculty for the Future Program and the Resnick Sustainability Institute. C.T.J. acknowledges the support of the National Science Foundation Graduate Research Fellowships Program. We acknowledge support of a Burroughs Wellcome Fund Career Award at the Scientific Interface (CASI) (M.P.L.), a Beckman Foundation Young Investigator Award (M.P.L.), a USDA AFRI award (M.P.L.), a USDA NIFA award (M.P.L.), a CZI deep tissue imaging award (M.P.L.), and an FFAR New Innovator Award (M.P.L.). M.P.L. is a Chan Zuckerberg Biohub investigator. This research was supported, in part, by the US Department of Energy, Office of Science, Office of Biological and Environmental Research, Genomic Science Program grant no. DE-DE-SC0020366 (S.Y.R., J.C.M., M.P.L. and D.W.E.) and DE-SC0018277 (S.Y.R.), the DOE Joint BioEnergy Institute (http://www.jbei.org) supported by the US Department of Energy, Office of Science, Office of Biological and Environmental Research, through contract DE-AC02-05CH11231 between Lawrence Berkeley National Laboratory (J.C.M.) and the US Department of Energy, and the US National Science Foundation grants IOS-1546838 (S.Y.R.) and MCB-1617020 (S.Y.R.). \n\nThe authors declare no competing interests. \n\nPeer review information. Nature Nanotechnology thanks Sandeep Kumar, Neena Mitter, Yiping Qi and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.", "abstract": "CRISPR\u2013Cas genetic engineering of plants holds tremendous potential for providing food security, battling biotic and abiotic crop stresses caused by climate change, and for environmental remediation and sustainability. Since the discovery of CRISPR\u2013Cas technology, its usefulness has been demonstrated widely, including for genome editing in plants. Despite the revolutionary nature of genome-editing tools and the notable progress that these tools have enabled in plant genetic engineering, there remain many challenges for CRISPR applications in plant biotechnology. Nanomaterials could address some of the most critical challenges of CRISPR genome editing in plants through improvements in cargo delivery, species independence, germline transformation and gene editing efficiency. This Perspective identifies major barriers preventing CRISPR-mediated plant genetic engineering from reaching its full potential, and discusses ways that nanoparticle technologies can lower or eliminate these barriers. We also describe advances that are needed in nanotechnology to facilitate and accelerate plant genome editing. Timely advancement of the application of CRISPR technologies in plant engineering is crucial for our ability to feed and sustain the growing human population under a changing global climate.", "date": "2021-03", "date_type": "published", "publication": "Nature Nanotechnology", "volume": "16", "number": "3", "publisher": "Nature Publishing Group", "pagerange": "243-250", "id_number": "CaltechAUTHORS:20220302-323754000", "issn": "1748-3387", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220302-323754000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Schlumberger Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Burroughs Wellcome Fund" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Department of Agriculture" }, { "agency": "Chan-Zuckerberg Biohub" }, { "agency": "Foundation for Food and Agriculture Research" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020366" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0018277" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "IOS-1546838" }, { "agency": "NSF", "grant_number": "MCB-1617020" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41565-021-00854-y", "pub_year": "2021", "author_list": "Demirer, Gozde S.; Silva, Tallyta N.; et al." }, { "id": "https://authors.library.caltech.edu/records/jk4kd-j8n07", "eprint_id": 107358, "eprint_status": "archive", "datestamp": "2023-08-20 01:52:52", "lastmod": "2023-10-20 23:03:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ming-Yi", "name": { "family": "Ming", "given": "Yi" }, "orcid": "0000-0002-5324-1305" }, { "id": "Lin-Pu", "name": { "family": "Lin", "given": "Pu" }, "orcid": "0000-0003-2577-6094" }, { "id": "Naik-Vaishali", "name": { "family": "Naik", "given": "Vaishali" }, "orcid": "0000-0002-2254-1700" }, { "id": "Paulot-Fabien", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Horowitz-Larry-W", "name": { "family": "Horowitz", "given": "Larry W." }, "orcid": "0000-0002-5886-3314" }, { "id": "Ginoux-Paul-A", "name": { "family": "Ginoux", "given": "Paul A." }, "orcid": "0000-0003-3642-2988" }, { "id": "Ramaswamy-Venkatachalam", "name": { "family": "Ramaswamy", "given": "V." }, "orcid": "0000-0002-1984-6423" }, { "id": "Loeb-Norman-G", "name": { "family": "Loeb", "given": "Norman G." }, "orcid": "0000-0002-2538-9644" }, { "id": "Shen-Zhaoyi", "name": { "family": "Shen", "given": "Zhaoyi" }, "orcid": "0000-0002-0444-4720" }, { "id": "Singer-Clare-E", "name": { "family": "Singer", "given": "Clare E." }, "orcid": "0000-0002-1708-0997" }, { "id": "Ward-Ryan-X", "name": { "family": "Ward", "given": "Ryan X." }, "orcid": "0000-0003-2317-3310" }, { "id": "Zhang-Zhibo", "name": { "family": "Zhang", "given": "Zhibo" }, "orcid": "0000-0001-9491-1654" }, { "id": "Bellouin-Nicolas", "name": { "family": "Bellouin", "given": "Nicolas" }, "orcid": "0000-0003-2109-9559" } ] }, "title": "Assessing the Influence of COVID\u201019 on the Shortwave Radiative Fluxes Over the East Asian Marginal Seas", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020. The Authors. This article has been contributed to by US Government employees and their work is in the public domain in the USA. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 02 February 2021; Version of Record online: 02 February 2021; Accepted manuscript online: 29 December 2020; Manuscript accepted: 23 December 2020; Manuscript revised: 21 December 2020; Manuscript received: 12 November 2020. \n\nThe authors thank L. Donner and D. Paynter for their helpful comments on an early draft. Z. Shen acknowledges support from the Ronald and Maxine Linde Challenge for Climate Science Fund. C. E. Singer acknowledges support from the NSF Graduate Research Fellowship under Grant No. DGE\u20101745301. R. X. Ward. acknowledges fellowship support from the Resnick Sustainability Institute at Caltech. \n\nData Availability Statement: The AQUA/MODIS MYD08 L3 Global 1 Deg. data set was acquired from the Level\u20101 and Atmosphere Archive and Distribution System (LAADS) Distributed Active Archive Center (DAAC), located in the Goddard Space Flight Center in Greenbelt, Maryland (https://ladsweb.nascom.nasa.gov/). The CERES data were obtained from the NASA Langley Research Center Atmospheric Science Data Center (https://doi.org/10.5067/TERRA-AQUA/CERES/EBAF-TOA_L3B004.1). Primary AM4 simulation results that may be used to produce the plots are available are available online (https://data.caltech.edu/records/1666).\n\n

Published - 2020GL091699.pdf

Supplemental Material - 2020gl091699-sup-0001-supporting_information_si-s01.docx

", "abstract": "The Coronavirus Disease 2019 (COVID\u201019) pandemic led to a widespread reduction in aerosol emissions. Using satellite observations and climate model simulations, we study the underlying mechanisms of the large decreases in solar clear\u2010sky reflection (3.8 W m\u207b\u00b2 or 7%) and aerosol optical depth (0.16 W m\u207b\u00b2 or 32%) observed over the East Asian Marginal Seas in March 2020. By separating the impacts from meteorology and emissions in the model simulations, we find that about one\u2010third of the clear\u2010sky anomalies can be attributed to pandemic\u2010related emission reductions, and the rest to weather variability and long\u2010term emission trends. The model is skillful at reproducing the observed interannual variations in solar all\u2010sky reflection, but no COVID\u201019 signal is discerned. The current observational and modeling capabilities will be critical for monitoring, understanding, and predicting the radiative forcing and climate impacts of the ongoing crisis.", "date": "2021-02-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "48", "number": "3", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020GL091699", "id_number": "CaltechAUTHORS:20210107-101118570", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210107-101118570", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ronald And Maxine Linde Center for Global Environmental Science" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "COVID-19" } ] }, "doi": "10.1029/2020gl091699", "primary_object": { "basename": "2020GL091699.pdf", "url": "https://authors.library.caltech.edu/records/jk4kd-j8n07/files/2020GL091699.pdf" }, "related_objects": [ { "basename": "2020gl091699-sup-0001-supporting_information_si-s01.docx", "url": "https://authors.library.caltech.edu/records/jk4kd-j8n07/files/2020gl091699-sup-0001-supporting_information_si-s01.docx" } ], "pub_year": "2021", "author_list": "Ming, Yi; Lin, Pu; et al." }, { "id": "https://authors.library.caltech.edu/records/pr2s0-x0n39", "eprint_id": 107302, "eprint_status": "archive", "datestamp": "2023-08-20 01:23:36", "lastmod": "2023-10-23 15:43:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Martinolich-Andrew-J", "name": { "family": "Martinolich", "given": "Andrew J." }, "orcid": "0000-0002-7866-9594" }, { "id": "Zak-Joshua-J", "name": { "family": "Zak", "given": "Joshua J." }, "orcid": "0000-0003-3793-7254" }, { "id": "Agyeman-Budu-David-N", "name": { "family": "Agyeman-Budu", "given": "David N." } }, { "id": "Kim-Seong-Shik", "name": { "family": "Kim", "given": "Seong Shik" }, "orcid": "0000-0003-2604-6392" }, { "id": "Bashian-Nicholas-H", "name": { "family": "Bashian", "given": "Nicholas H." }, "orcid": "0000-0001-9984-2539" }, { "id": "Irshad-Ahamed", "name": { "family": "Irshad", "given": "Ahamed" }, "orcid": "0000-0001-7107-9623" }, { "id": "Narayan-Sri-R", "name": { "family": "Narayan", "given": "Sri R." }, "orcid": "0000-0002-7259-3728" }, { "id": "Melot-Brent-C", "name": { "family": "Melot", "given": "Brent C." }, "orcid": "0000-0002-7078-8206" }, { "id": "Nelson-Weker-Johanna", "name": { "family": "Nelson Weker", "given": "Johanna" }, "orcid": "0000-0001-6856-3203" }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Controlling Covalency and Anion Redox Potentials through Anion Substitution in Li-Rich Chalcogenides", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: October 26, 2020; Revised: December 10, 2020; Published: December 30, 2020. \n\nThis work was supported as part of the Center for Synthetic Control Across Length-scales for Advancing Rechargeables (SCALAR), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award No. DE-SC0019381. A.J.M. acknowledges support through a postdoctoral fellowship from the Resnick Sustainability Institute at Caltech. J.J.Z. acknowledges support from the National Science Foundation Graduate Research Fellowship under Grant. No. DGE-1745301. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. \n\nAuthor Contributions. (A.J.M. and J.J.Z.) These authors contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cm0c04164_si_001.pdf

", "abstract": "Development of next-generation battery technologies is imperative in the pursuit of a clean energy future. Toward that end, battery chemistries capable of multielectron redox processes are at the forefront of studies on Li-based systems to increase the gravimetric capacity of the cathode. Multielectron processes rely either on the iterative redox of transition metal cations or redox involving both the transition metal cations and the anionic framework. Targeting coupled cation and anion redox to achieve multielectron charge storage is difficult, however, because the structure\u2013property relationships that govern reversibility are poorly understood. In an effort to develop fundamental understanding of anion redox, we have developed a materials family that displays tunable anion redox over a range of potentials that are dependent on a systematic modification of the stoichiometry. We report anion redox in the chalcogenide solid solution Li\u2082FeS_(2\u2013y)Se_y, wherein the mixing of the sulfide and selenide anions yields a controllable shift in the high voltage oxidation plateau. Electrochemical measurements indicate that reversible multielectron redox occurs across the solid solution. X-ray absorption spectroscopy supports the oxidation of both iron and selenium at high states of charge, while Raman spectroscopy indicates the formation of Se\u2013Se dimers in Li\u2082FeSe\u2082 upon Li deintercalation, providing insight into the charge mechanism of the Li-rich iron chalcogenides. Anion substitution presents direct control over the functional properties of multielectron redox materials for next generation battery technologies.", "date": "2021-01-12", "date_type": "published", "publication": "Chemistry of Materials", "volume": "33", "number": "1", "publisher": "American Chemical Society", "pagerange": "378-391", "id_number": "CaltechAUTHORS:20210104-164230745", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210104-164230745", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019381" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemmater.0c04164", "primary_object": { "basename": "cm0c04164_si_001.pdf", "url": "https://authors.library.caltech.edu/records/pr2s0-x0n39/files/cm0c04164_si_001.pdf" }, "pub_year": "2021", "author_list": "Martinolich, Andrew J.; Zak, Joshua J.; et al." }, { "id": "https://authors.library.caltech.edu/records/ahjnd-vnf17", "eprint_id": 113701, "eprint_status": "archive", "datestamp": "2023-08-22 08:24:55", "lastmod": "2025-11-18 22:54:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Demirer-G\u00f6zde-S", "name": { "family": "Demirer", "given": "Gozde S." }, "orcid": "0000-0002-3007-1489" }, { "id": "Landry-Markita-P", "name": { "family": "Landry", "given": "Markita P." }, "orcid": "0000-0002-5832-8522" } ] }, "title": "Efficient Transient Gene Knock-down in Tobacco Plants Using Carbon Nanocarriers", "ispublished": "pub", "full_text_status": "public", "keywords": "Plant gene silencing, RNA interference, siRNA delivery, Gene knock-down, Nicotiana benthamiana, Carbon nanotubes, Single-walled carbon nanotubes (SWNT), Nanomaterial; General Medicine", "note": "\u00a9 2021 The Authors; exclusive licensee Bio-protocol LLC. \n\nThis protocol is derived from Demirer et al. (2020). \n\nG.S.D. is supported by the Schlumberger Foundation Faculty for the Future Program and Caltech Resnick Sustainability Institute. We acknowledge support of a Burroughs Wellcome Fund Career Award at the Scientific Interface (CASI), a Stanley Fahn PDF Junior Faculty Grant with Award # PFJFA-1760, a Beckman Foundation Young Investigator Award, a USDA AFRI award, a USDA NIFA award, the Moore Foundation, and an FFAR New Innovator Award (M.P.L). M.P.L. is a Chan-Zuckerberg Biohub investigator. \n\nAuthors declare no competing interest.\n\n

Published - BioProtoc-11-01-3897.pdf

", "abstract": "Gene knock-down in plants is a useful approach to study genotype-phenotype relationships, render disease resistance to crops, and enable efficient biosynthesis of molecules in plants. Small interfering RNA (siRNA)-mediated gene silencing is one of the most common ways to achieve gene knock-down in plants. Traditionally, siRNA is delivered into intact plant cells by coding the siRNA sequences into DNA vectors, which are then delivered through viral and/or bacterial methods. In this protocol, we provide an alternative direct delivery method of siRNA molecules into intact plant cells for efficient transient gene knock-down in model tobacco plant, Nicotiana benthamiana, leaves. Our approach uses one dimensional carbon-based nanomaterials, single-walled carbon nanotubes (SWNTs), to deliver siRNA, and does not rely on viral/bacterial delivery. The distinct advantages of our method are i) there is no need for DNA coding of siRNA sequences, ii) this abiotic method could work in a broader range of plant species than biotic methods, and iii) there are fewer regulatory complications when using abiotic delivery methods, whereby gene silencing is transient without permanent modification of the plant genome.", "date": "2021-01-05", "date_type": "published", "publication": "Bio-protocol", "volume": "11", "number": "1", "publisher": "Bio-Protocol", "pagerange": "Art. No. e3897", "id_number": "CaltechAUTHORS:20220302-323885000", "issn": "2331-8325", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220302-323885000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Schlumberger Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Burroughs Wellcome Fund" }, { "agency": "Parkinson's Foundation", "grant_number": "PFJFA-1760" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Department of Agriculture" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Foundation for Food Research" }, { "agency": "Chan-Zuckerberg Biohub" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.21769/bioprotoc.3897", "pmcid": "PMC7953349", "primary_object": { "basename": "BioProtoc-11-01-3897.pdf", "url": "https://authors.library.caltech.edu/records/ahjnd-vnf17/files/BioProtoc-11-01-3897.pdf" }, "pub_year": "2021", "author_list": "Demirer, Gozde S. and Landry, Markita P." }, { "id": "https://authors.library.caltech.edu/records/g85f2-4tz54", "eprint_id": 102659, "eprint_status": "archive", "datestamp": "2023-08-20 01:11:04", "lastmod": "2023-10-20 00:23:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Shen-Boqiang", "name": { "family": "Shen", "given": "Boqiang" }, "orcid": "0000-0003-0697-508X" }, { "id": "Suh-Myoung-Gyun", "name": { "family": "Suh", "given": "Myoung-Gyun" }, "orcid": "0000-0002-9527-0585" }, { "id": "Wang-Heming", "name": { "family": "Wang", "given": "Heming" }, "orcid": "0000-0003-3861-0624" }, { "id": "Safak-Kemal", "name": { "family": "Safak", "given": "Kemal" } }, { "id": "Dai-Anan", "name": { "family": "Dai", "given": "Anan" } }, { "id": "Matsko-Andrey-B", "name": { "family": "Matsko", "given": "Andrey B." } }, { "id": "K\u00e4rtner-Franz-X", "name": { "family": "K\u00e4rtner", "given": "Franz X." } }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry" }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Oscillatory motion of a counterpropagating Kerr soliton dimer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Physical Society. \n\nReceived 25 February 2020; revised 15 December 2020; accepted 18 December 2020; published 6 January 2021. \n\nThis work was supported by the Air Force Office of Scientific Research (Grant No. FA9550-18-1-0353) and the Kavli Nanoscience Institute. C.B. gratefully acknowledges the postdoctoral fellowship from the Resnick Sustainability Institute at Caltech. The research performed by A.M. was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (No. 80NM0018D0004). We thank Qi-Fan Yang for helpful discussion.\n\n

Published - PhysRevA.103.L011501.pdf

Submitted - 2003.00573.pdf

Supplemental Material - Forced_Motion_SI.pdf

", "abstract": "Counterpropagating (CP) solitons generated in high-Q microcavities not only offer useful dual-comb sources, but also provide a new platform to study soliton interactions. Here, we demonstrate and theoretically explain a manifestation of soliton trapping that occurs between CP solitons in a silica microcavity introducing a Kerr soliton dimer. In conventional soliton trapping, the group velocities of two solitons can be synchronized by a Kerr-effect-mediated interaction. The solitons can then copropagate with a fixed temporal delay. However, as shown here, when counterpumping a microcavity using slightly detuned pump frequencies and in the presence of backscattering, the group velocities of clockwise and counterclockwise solitons undergo periodic modulation instead of being locked to a constant velocity. Upon emission from the microcavity, the solitons feature a relative oscillatory motion around a locked average relative displacement with an amplitude that can be larger than the soliton pulse width. This relative motion introduces a sideband fine structure into the optical spectrum of the CP solitons. Our observation provides insights on coherently pumped soliton dimers in microcavities.", "date": "2021-01", "date_type": "published", "publication": "Physical Review A", "volume": "103", "number": "1", "publisher": "American Physical Society", "pagerange": "Art. No. L011501", "id_number": "CaltechAUTHORS:20200420-125418330", "issn": "2469-9926", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200420-125418330", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0353" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.48550/arXiv.2003.00573", "primary_object": { "basename": "2003.00573.pdf", "url": "https://authors.library.caltech.edu/records/g85f2-4tz54/files/2003.00573.pdf" }, "related_objects": [ { "basename": "Forced_Motion_SI.pdf", "url": "https://authors.library.caltech.edu/records/g85f2-4tz54/files/Forced_Motion_SI.pdf" }, { "basename": "PhysRevA.103.L011501.pdf", "url": "https://authors.library.caltech.edu/records/g85f2-4tz54/files/PhysRevA.103.L011501.pdf" } ], "pub_year": "2021", "author_list": "Bao, Chengying; Shen, Boqiang; et al." }, { "id": "https://authors.library.caltech.edu/records/0hpmn-9pp50", "eprint_id": 104243, "eprint_status": "archive", "datestamp": "2023-08-22 08:08:16", "lastmod": "2023-10-20 19:12:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Chen", "name": { "family": "Liang", "given": "Chen" } }, { "id": "Guo-Linqi", "name": { "family": "Guo", "given": "Linqi" } }, { "id": "Zocca-Alessandro", "name": { "family": "Zocca", "given": "Alessandro" }, "orcid": "0000-0001-6585-4785" }, { "id": "Yu-Shuyue", "name": { "family": "Yu", "given": "Shuyue" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" } } ] }, "title": "An integrated approach for failure mitigation & localization in power systems", "ispublished": "pub", "full_text_status": "public", "keywords": "Cascading failure; Failure mitigation; Frequency control; Power system reliability; Topology design", "note": "\u00a9 2020 Elsevier B.V. \n\nReceived 5 October 2019, Revised 20 April 2020, Accepted 31 July 2020, Available online 8 August 2020. \n\nThis work has been supported by Resnick Fellowship, Linde Institute Research Award, NWO Rubicon grant 680.50.1529, NSF through awards ECCS 1619352, CNS 1545096, CCF 1637598, ECCS 1739355, CNS 1518941, CPS 154471, ARPA-E through award DE-AR0000699 (NODES), and DTRA through award HDTRA 1-15-1-0003. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\n

Submitted - 2004.10401.pdf

", "abstract": "The transmission grid is often comprised of several control areas that are connected by multiple tie lines in a mesh structure for reliability. It is also well-known that line failures can propagate non-locally and redundancy can exacerbate cascading. In this paper, we propose an integrated approach to grid reliability that (i) judiciously switches off a small number of tie lines so that the control areas are connected in a tree structure; and (ii) leverages a unified frequency control paradigm to provide congestion management in real time. Even though the proposed topology reduces redundancy, the integration of tree structure at regional level and real-time congestion management can provide stronger guarantees on failure localization and mitigation. We illustrate our approach on the IEEE 39-bus network and evaluate its performance on the IEEE 118-bus, 179-bus, 200-bus and 240-bus networks with various network congestion conditions. Simulations show that, compared with the traditional approach, our approach not only prevents load shedding in more failure scenarios, but also incurs smaller amounts of load loss in scenarios where load shedding is inevitable. Moreover, generators under our approach adjust their operations more actively and efficiently in a local manner.", "date": "2021-01", "date_type": "published", "publication": "Electric Power Systems Research", "volume": "190", "publisher": "Elsevier", "pagerange": "Art. No. 106613", "id_number": "CaltechAUTHORS:20200707-103725840", "issn": "0378-7796", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200707-103725840", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Linde Institute of Economic and Management Science" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "680.50.1529" }, { "agency": "NSF", "grant_number": "ECCS-1619352" }, { "agency": "NSF", "grant_number": "CNS-1545096" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "ECCS-1739355" }, { "agency": "NSF", "grant_number": "CNS-1518941" }, { "agency": "NSF", "grant_number": "CPS-154471" }, { "agency": "Advanced Research Projects Agency-Energy (ARPA-E)", "grant_number": "DE-AR0000699" }, { "agency": "Defense Threat Reduction Agency (DTRA)", "grant_number": "HDTRA 1-15-1-0003" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.48550/arXiv.2004.10401", "primary_object": { "basename": "2004.10401.pdf", "url": "https://authors.library.caltech.edu/records/0hpmn-9pp50/files/2004.10401.pdf" }, "pub_year": "2021", "author_list": "Liang, Chen; Guo, Linqi; et al." }, { "id": "https://authors.library.caltech.edu/records/jvh7d-16y03", "eprint_id": 106816, "eprint_status": "archive", "datestamp": "2023-08-22 08:03:00", "lastmod": "2023-10-23 19:31:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parker-Harrison-A", "name": { "family": "Parker", "given": "H. A." }, "orcid": "0000-0002-0041-2764" }, { "id": "Hasheminassab-Sina", "name": { "family": "Hasheminassab", "given": "S." }, "orcid": "0000-0002-4422-8547" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Impacts of Traffic Reductions Associated With COVID-19 on Southern California Air Quality", "ispublished": "pub", "full_text_status": "public", "keywords": "air quality; lockdown; COVID\u201019; South Coast Air Basin; ozone; nitrogen dioxide", "note": "\u00a9 2020 The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nIssue Online: 01 December 2020; Version of Record online: 01 December 2020; Accepted manuscript online: 23 November 2020; Manuscript accepted: 10 November 2020; Manuscript revised: 05 November 2020; Manuscript received: 01 August 2020. \n\nThe views expressed in this document are solely those of the authors and do not necessarily reflect those of the South Coast AQMD. The CITAQS facility was funded by Caltech's Linde Center for Global Environmental Science and the Resnick Sustainability Institute. We thank NASA via NNX17AE15G for support of retrievals of CH\u2082O from the Caltech TCCON station. Harrison Parker thanks the Rose Hill Foundation for initial support of his graduate fellowship. \n\nData Availability Statement: Data from the CITAQS are available by request and will be available online to the public in the near future. All data from the AQMD sites are available through the California Air Resources Board Air Quality Data Query Tool (https://www.arb.ca.gov/aqmis2/aqdselect.php). Data from the CalNex campaign are available online (https://www.esrl.noaa.gov/csl/projects/calnex/). TROPOMI data used in this research are available through the Sentinel\u20105P Data Hub (https://s5phub.copernicus.eu/). Traffic data used here are available through the Caltrans PeMS program (https://pems.dot.ca.gov/). Weather data are available online or by contacting the corresponding author (https://tccon\u2010weather.caltech.edu/).\n\n

Published - 2020GL090164.pdf

Supplemental Material - grl61597-sup-0001-2020gl090164-si-s01.pdf

", "abstract": "On 19 March 2020, California put in place Stay\u2010At\u2010Home orders to reduce the spread of SARS\u2010CoV\u20102. As a result, decreases up to 50% in traffic occurred across the South Coast Air Basin (SoCAB). We report that, compared to the 19 March to 30 June period of the last 5\u2009years, the 2020 concentrations of PM_(2.5) and NO_x showed an overall reduction across the basin. O\u2083 concentrations decreased in the western part of the basin and generally increased in the downwind areas. The NO_x decline in 2020 (approximately 27% basin\u2010wide) is in addition to ongoing declines over the last two decades (on average 4% less than the \u22126.8% per year afternoon NO\u2082 concentration decrease) and provides insight into how air quality may respond over the next few years of continued vehicular reductions. The modest changes in O\u2083 suggests additional mitigation will be necessary to comply with air quality standards.", "date": "2020-12-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "47", "number": "23", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020GL090164", "id_number": "CaltechAUTHORS:20201124-133212486", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201124-133212486", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ronald And Maxine Linde Center for Global Environmental Science" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA", "grant_number": "NNX17AE15G" }, { "agency": "Rose Hills Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "COVID-19" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020gl090164", "pmcid": "PMC7744837", "primary_object": { "basename": "2020GL090164.pdf", "url": "https://authors.library.caltech.edu/records/jvh7d-16y03/files/2020GL090164.pdf" }, "related_objects": [ { "basename": "grl61597-sup-0001-2020gl090164-si-s01.pdf", "url": "https://authors.library.caltech.edu/records/jvh7d-16y03/files/grl61597-sup-0001-2020gl090164-si-s01.pdf" } ], "pub_year": "2020", "author_list": "Parker, H. A.; Hasheminassab, S.; et al." }, { "id": "https://authors.library.caltech.edu/records/7r1eh-6pk43", "eprint_id": 107067, "eprint_status": "archive", "datestamp": "2023-08-22 07:57:55", "lastmod": "2023-10-23 15:29:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roumeli-Eleftheria", "name": { "family": "Roumeli", "given": "Eleftheria" }, "orcid": "0000-0002-2828-1428" }, { "id": "Ginsberg-Leah", "name": { "family": "Ginsberg", "given": "Leah" }, "orcid": "0000-0001-9685-7014" }, { "id": "McDonald-Robin", "name": { "family": "McDonald", "given": "Robin" } }, { "id": "Spigolon-Giada", "name": { "family": "Spigolon", "given": "Giada" }, "orcid": "0000-0002-1704-8372" }, { "id": "Hendrickx-Rodinde", "name": { "family": "Hendrickx", "given": "Rodinde" } }, { "id": "Ohtani-Misato", "name": { "family": "Ohtani", "given": "Misato" }, "orcid": "0000-0001-5429-3310" }, { "id": "Demura-Taku", "name": { "family": "Demura", "given": "Taku" }, "orcid": "0000-0002-2499-4738" }, { "id": "Ravichandran-G", "name": { "family": "Ravichandran", "given": "Guruswami" }, "orcid": "0000-0002-2912-0001" }, { "id": "Daraio-C", "name": { "family": "Daraio", "given": "Chiara" }, "orcid": "0000-0001-5296-4440" } ] }, "title": "Structure and Biomechanics during Xylem Vessel Transdifferentiation in Arabidopsis thaliana", "ispublished": "pub", "full_text_status": "public", "keywords": "plant biomechanics; turgor pressure; micro-compression; AFM; Arabidopsis thaliana; differentiation", "note": "\u00a9 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived: 27 October 2020; Revised: 30 November 2020; Accepted: 3 December 2020; Published: 5 December 2020. \n\nWe would like to acknowledge the contributions of Jenny Martinez, who conducted part of the micro-indentations in water, and Luca Bonanomi for helpful discussions. \n\nThis work was supported in part by the Resnick Sustainability Institute at Caltech (C.D.) and by the MEXT KAKENHI Grant Numbers JP18H05484 and JP18H05489 (M.O. and T.D.). \n\nAuthor Contributions: Conceptualization, E.R., M.O., T.D. and C.D.; methodology, E.R.; data analysis, E.R., L.G., R.M., G.S.; data curation, E.R., L.G.; Writing\u2014Original draft preparation, E.R., L.G.; Writing\u2014Review and editing, E.R., L.G., R.M., G.S., R.H., M.O., T.D., G.R., and C.D.; visualization, E.R., L.G., R.M., G.S. All authors have read and agreed to the published version of the manuscript. \n\nThe authors declare no conflict of interest.\n\n

Published - plants-09-01715.pdf

", "abstract": "Individual plant cells are the building blocks for all plantae and artificially constructed plant biomaterials, like biocomposites. Secondary cell walls (SCWs) are a key component for mediating mechanical strength and stiffness in both living vascular plants and biocomposite materials. In this paper, we study the structure and biomechanics of cultured plant cells during the cellular developmental stages associated with SCW formation. We use a model culture system that induces transdifferentiation of Arabidopsis thaliana cells to xylem vessel elements, upon treatment with dexamethasone (DEX). We group the transdifferentiation process into three distinct stages, based on morphological observations of the cell walls. The first stage includes cells with only a primary cell wall (PCW), the second covers cells that have formed a SCW, and the third stage includes cells with a ruptured tonoplast and partially or fully degraded PCW. We adopt a multi-scale approach to study the mechanical properties of cells in these three stages. We perform large-scale indentations with a micro-compression system in three different osmotic conditions. Atomic force microscopy (AFM) nanoscale indentations in water allow us to isolate the cell wall response. We propose a spring-based model to deconvolve the competing stiffness contributions from turgor pressure, PCW, SCW and cytoplasm in the stiffness of differentiating cells. Prior to triggering differentiation, cells in hypotonic pressure conditions are significantly stiffer than cells in isotonic or hypertonic conditions, highlighting the dominant role of turgor pressure. Plasmolyzed cells with a SCW reach similar levels of stiffness as cells with maximum turgor pressure. The stiffness of the PCW in all of these conditions is lower than the stiffness of the fully-formed SCW. Our results provide the first experimental characterization of the mechanics of SCW formation at single cell level.", "date": "2020-12-05", "date_type": "published", "publication": "Plants", "volume": "9", "number": "12", "publisher": "MDPI AG", "pagerange": "Art. No. 1715", "id_number": "CaltechAUTHORS:20201214-121033243", "issn": "2223-7747", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201214-121033243", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)", "grant_number": "JP18H05484" }, { "agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)", "grant_number": "JP18H05489" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.3390/plants9121715", "pmcid": "PMC7762020", "primary_object": { "basename": "plants-09-01715.pdf", "url": "https://authors.library.caltech.edu/records/7r1eh-6pk43/files/plants-09-01715.pdf" }, "pub_year": "2020", "author_list": "Roumeli, Eleftheria; Ginsberg, Leah; et al." }, { "id": "https://authors.library.caltech.edu/records/8hkmq-h5806", "eprint_id": 107378, "eprint_status": "archive", "datestamp": "2023-08-22 07:52:12", "lastmod": "2023-10-23 15:49:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Zachary-J", "name": { "family": "Lee", "given": "Zachary J." }, "orcid": "0000-0002-5358-2388" }, { "id": "Pang-John-Z-F", "name": { "family": "Pang", "given": "John Z. F." }, "orcid": "0000-0002-6485-7922" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Pricing EV charging service with demand charge", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Demand charge; EV Charging; Pricing; Smart charging; Online scheduling", "note": "\u00a9 2020 Elsevier B.V. \n\nReceived 5 October 2019, Revised 20 April 2020, Accepted 1 August 2020, Available online 4 September 2020. \n\nThis material is based upon work supported by NSF through grants CCF 1637598, ECCS 1619352, and CPS including grant 1739355, as well fellowship support through the NSF Graduate Research Fellowship Program 1745301 and Resnick Sustainability Institute. \n\nDeclaration of Competing Interest: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Steven Low is a co-founder of Caltech startup PowerFlex Systems, Inc. that deploys and operates ACN. Zachary Lee is a consultant for PowerFlex Systems, Inc. that deploys and operates ACN.", "abstract": "Pricing electric vehicle (EV) charging services is difficult when the electricity tariff includes both time-of-use energy cost and demand charge based on peak power draw. In this paper, we propose a pricing scheme that assigns a session-specific energy price to each charging session at the end of the billing period. The session price precisely captures the costs of energy, demand charge, and infrastructure congestion for which that session is responsible in that month while optimizing the trade-off between inexpensive time-of-use pricing and peak power draw. While our pricing scheme is calculated offline at the end of the billing period, we propose an online scheduling algorithm based on model predictive control to determine charging rates for each EV in real-time. We provide theoretical justification for our proposal and support it with simulations using real data collected from charging facilities at Caltech and JPL. Our simulation results suggest that the online algorithm can approximate the offline optimal reasonably well, e.g., the cost paid by the operator in the online setting is higher than the offline optimal cost by 9.2% and 6.5% at Caltech and JPL respectively. In the case of JPL, congestion rents are enough to cover this increase in costs, while at Caltech, this results in a negligible average loss of $18 per month.", "date": "2020-12", "date_type": "published", "publication": "Electric Power Systems Research", "volume": "189", "publisher": "Elsevier", "pagerange": "Art. No. 106694", "id_number": "CaltechAUTHORS:20210107-153400550", "issn": "0378-7796", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210107-153400550", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "ECCS-1619352" }, { "agency": "NSF", "grant_number": "ECCS-1739355" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.epsr.2020.106694", "pub_year": "2020", "author_list": "Lee, Zachary J.; Pang, John Z. F.; et al." }, { "id": "https://authors.library.caltech.edu/records/zkxdz-e5z50", "eprint_id": 106643, "eprint_status": "archive", "datestamp": "2023-08-20 00:28:42", "lastmod": "2023-10-20 23:39:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hamann-Kathryn-R", "name": { "family": "Hamann", "given": "Kathryn R." }, "orcid": "0000-0003-1163-7173" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Path-Dependent Morphological Evolution of Se\u2013Te Mesostructures Prepared by Inorganic Phototropic Growth", "ispublished": "pub", "full_text_status": "public", "keywords": "Morphology, Crystallization, Absorption, Deposition, Quantum mechanics", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: September 13, 2020;\nPublished: November 11, 2020.\n\nThis work was supported by the \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award Number DE-SC0001293 and was also supported by the National Science Foundation, Directorate for Mathematical & Physical Sciences, Division of Materials Research, under Award Number DMR 1905963. The authors gratefully acknowledge J. Thompson for insightful discussions, E. Simonoff and S. Yalamanchili for assistance with substrate preparation, and R. Gerhart, N. Hart, and B. Markowicz for assistance with photoelectrochemical cell fabrication. K.R.H. and M.C.M. acknowledge Graduate Research Fellowships from the National Science Foundation. M.C.M. also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja0c09798_si_001.pdf

", "abstract": "We describe herein a path-dependent \"history\" effect wherein the film morphology generated in the second step of a two-step inorganic phototropic growth process depends on a preexisting structure that has been first grown under different optical stimulation conditions. Se\u2013Te generated with static illumination exhibited a highly anisotropic lamellar morphology with a characteristic feature pitch proportional to the input wavelength. Growth using first a short wavelength of light, followed by growth using a longer wavelength, resulted in the second-stage morphology exhibiting termination of lamellae formed during the first growth step. The lamellar pitch at the end of the second growth step was larger than that effected in the first step. In contrast, use of the same input wavelengths but in the opposite order produced no change in the feature pitch but rather only linear feature extension. Analysis of light absorption in simulated structures, in tandem with the empirical data, indicated that the history effect and asymmetric path dependence are a result of emergent nanophotonic processes at the growth interface that dynamically shape the optical field and direct morphological evolution of the photodeposit in a continuous feedback loop.", "date": "2020-11-25", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "142", "number": "47", "publisher": "American Chemical Society", "pagerange": "19840-19843", "id_number": "CaltechAUTHORS:20201112-103612027", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201112-103612027", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "NSF", "grant_number": "DMR-1905963" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.0c09798", "primary_object": { "basename": "ja0c09798_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zkxdz-e5z50/files/ja0c09798_si_001.pdf" }, "pub_year": "2020", "author_list": "Hamann, Kathryn R.; Carim, Azhar I.; et al." }, { "id": "https://authors.library.caltech.edu/records/v466c-hvh40", "eprint_id": 106306, "eprint_status": "archive", "datestamp": "2023-08-20 00:15:54", "lastmod": "2023-10-20 23:19:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schild-D-J", "name": { "family": "Schild", "given": "Dirk J." } }, { "id": "Drover-M-W", "name": { "family": "Drover", "given": "Marcus W." }, "orcid": "0000-0002-2186-1040" }, { "id": "Oyala-P-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Generating Potent C\u2013H PCET Donors: Ligand-Induced Fe-to-Ring Proton Migration from a Cp*Fe^(III)\u2013H Complex Demonstrates a Promising Strategy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: August 31, 2020; Published: October 26, 2020. \n\nThe authors are grateful to the Department of Energy Basic Energy Sciences for support via Grant No. DOE-0235032. The Caltech EPR facility was previously supported by the National Science Foundation via Grant No. NSF MRI-153194 and is currently supported by the Dow Next Generation Educator Fund. The Beckman Institute is thanked for X-ray support. M.W.D. acknowledges NSERC (Banting PDF award), and M.W.D. and D.J.S. thank the Resnick Sustainability Institute at Caltech for fellowships. \n\nAuthor Contributions: D.J.S. and M.W.D. contributed equally.\n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja0c09363_si_001.pdf

Supplemental Material - ja0c09363_si_002.cif

Supplemental Material - ja0c09363_si_003.mol

", "abstract": "Highly reactive organometallic species that mediate reductive proton-coupled electron transfer (PCET) reactions are an exciting area for development in catalysis, where a key objective focuses on tuning the reactivity of such species. This work pursues ligand-induced activation of a stable organometallic complex toward PCET reactivity. This is studied via the conversion of a prototypical Cp*Fe^(III)\u2013H species, [Fe^(III)(\u03b7\u2075-Cp*)(dppe)H]\u207a (Cp* = C\u2085Me\u2085\u207b, dppe = 1,2-bis(diphenylphosphino)ethane), to a highly reactive, S = 1/2 ring-protonated endo-Cp*H\u2013Fe relative, triggered by the addition of CO. Our assignment of the latter ring-protonated species contrasts with its previous reported formulation, which instead assigned it as a hypervalent 19-electron hydride, [Fe^(III)(\u03b7\u2075-Cp*)(dppe)(CO)H]\u207a. Herein, pulse EPR spectroscopy (^(1,2)H HYSCORE, ENDOR) and X-ray crystallography, with corresponding DFT studies, cement its assignment as the ring-protonated isomer, [Fe^I(endo-\u03b7\u2074-Cp*H)(dppe)(CO)] \u207a. A less sterically shielded and hence more reactive exo-isomer can be generated through oxidation of a stable Fe0(exo-\u03b7\u2074-Cp*H)(dppe)(CO) precursor. Both endo- and exo-ring-protonated isomers are calculated to have an exceptionally low bond dissociation free energy (BDFE_(C\u2013H) \u2248 29 kcal mol\u207b\u00b9 and 25 kcal mol\u207b\u00b9, respectively) cf. BDFE_(Fe\u2013H) of 56 kcal mol\u207b\u00b9 for [Fe^(III)(\u03b7\u2075-Cp*)(dppe)H] \u207a. These weak C\u2013H bonds are shown to undergo proton-coupled electron transfer (PCET) to azobenzene to generate diphenylhydrazine and the corresponding closed-shell [Fe^(II)(\u03b7\u2075-Cp*)(dppe)CO]\u207a byproduct.", "date": "2020-11-04", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "142", "number": "44", "publisher": "American Chemical Society", "pagerange": "18963-18970", "id_number": "CaltechAUTHORS:20201027-151729690", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201027-151729690", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "NSF", "grant_number": "MRI-153194" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.0c09363", "primary_object": { "basename": "ja0c09363_si_001.pdf", "url": "https://authors.library.caltech.edu/records/v466c-hvh40/files/ja0c09363_si_001.pdf" }, "related_objects": [ { "basename": "ja0c09363_si_002.cif", "url": "https://authors.library.caltech.edu/records/v466c-hvh40/files/ja0c09363_si_002.cif" }, { "basename": "ja0c09363_si_003.mol", "url": "https://authors.library.caltech.edu/records/v466c-hvh40/files/ja0c09363_si_003.mol" } ], "pub_year": "2020", "author_list": "Schild, Dirk J.; Drover, Marcus W.; et al." }, { "id": "https://authors.library.caltech.edu/records/x2w3a-2k430", "eprint_id": 106101, "eprint_status": "archive", "datestamp": "2023-08-22 07:06:40", "lastmod": "2023-10-23 17:23:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lopez\u2010Gomez-I", "name": { "family": "Lopez\u2010Gomez", "given": "Ignacio" }, "orcid": "0000-0002-7255-5895" }, { "id": "Cohen-Y", "name": { "family": "Cohen", "given": "Yair" }, "orcid": "0000-0002-9615-2476" }, { "id": "He-Jia", "name": { "family": "He", "given": "Jia" } }, { "id": "Jaruga-Anna", "name": { "family": "Jaruga", "given": "Anna" }, "orcid": "0000-0003-3194-6440" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "A Generalized Mixing Length Closure for Eddy-Diffusivity Mass-Flux Schemes of Turbulence and Convection", "ispublished": "pub", "full_text_status": "public", "keywords": "boundary layer turbulence; subgrid\u2010scale parameterization; eddy\u2010diffusivity mass\u2010flux scheme", "note": "\u00a9 2020 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 29 October 2020; Version of Record online: 29 October 2020; Accepted manuscript online: 14 October 2020; Manuscript accepted: 07 October 2020; Manuscript revised: 02 September 2020; Manuscript received: 01 May 2020. \n\nThis research was made possible by the generosity of Eric and Wendy Schmidt by recommendation of the Schmidt Futures program, by Earthrise Alliance, Mountain Philanthropies, the Paul G. Allen Family Foundation, and the National Science Foundation (NSF, Award AGS1835860)). I. L. would like to thank the Resnick Sustainability Institute at Caltech for fellowship support. Parts of the research were carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration and funded through the Internal Research and Technology Development Program. We thank Gregory L. Wagner and two anonymous reviewers for helpful comments on an earlier version of this paper. \u00a9 2020. California Institute of Technology. Government sponsorship acknowledged. \n\nData Availability Statement: The PyCLES code used to generate LES results is available online (climate\u2010dynamics.org/software/#pycles). The SCM code is available at https://doi.org/10.5281/zenodo.3789011 website. All LES and SCM data are publicly available online (https://doi.org/10.5281/zenodo.3996252).\n\n

Published - 2020MS002161.pdf

Submitted - essoar.10502906.1.pdf

", "abstract": "Because of their limited spatial resolution, numerical weather prediction and climate models have to rely on parameterizations to represent atmospheric turbulence and convection. Historically, largely independent approaches have been used to represent boundary layer turbulence and convection, neglecting important interactions at the subgrid scale. Here we build on an eddy\u2010diffusivity mass\u2010flux (EDMF) scheme that represents all subgrid\u2010scale mixing in a unified manner, partitioning subgrid\u2010scale fluctuations into contributions from local diffusive mixing and coherent advective structures and allowing them to interact within a single framework. The EDMF scheme requires closures for the interaction between the turbulent environment and the plumes and for local mixing. A second\u2010order equation for turbulence kinetic energy (TKE) provides one ingredient for the diffusive local mixing closure, leaving a mixing length to be parameterized. Here, we propose a new mixing length formulation, based on constraints derived from the TKE balance. It expresses local mixing in terms of the same physical processes in all regimes of boundary layer flow. The formulation is tested at a range of resolutions and across a wide range of boundary layer regimes, including a stably stratified boundary layer, a stratocumulus\u2010topped marine boundary layer, and dry convection. Comparison with large eddy simulations (LES) shows that the EDMF scheme with this diffusive mixing parameterization accurately captures the structure of the boundary layer and clouds in all cases considered.", "date": "2020-11", "date_type": "published", "publication": "Journal of Advances in Modeling Earth Systems", "volume": "12", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020MS002161", "id_number": "CaltechAUTHORS:20201015-152734310", "issn": "1942-2466", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201015-152734310", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Schmidt Futures Program" }, { "agency": "Earthrise Alliance" }, { "agency": "Mountain Philanthropies" }, { "agency": "Paul G. Allen Family Foundation" }, { "agency": "NSF", "grant_number": "AGS-1835860" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020ms002161", "primary_object": { "basename": "essoar.10502906.1.pdf", "url": "https://authors.library.caltech.edu/records/x2w3a-2k430/files/essoar.10502906.1.pdf" }, "related_objects": [ { "basename": "2020MS002161.pdf", "url": "https://authors.library.caltech.edu/records/x2w3a-2k430/files/2020MS002161.pdf" } ], "pub_year": "2020", "author_list": "Lopez\u2010Gomez, Ignacio; Cohen, Yair; et al." }, { "id": "https://authors.library.caltech.edu/records/j02ha-dmz20", "eprint_id": 105375, "eprint_status": "archive", "datestamp": "2023-08-19 23:57:29", "lastmod": "2025-04-23 03:11:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Yi-Rung", "name": { "family": "Lin", "given": "Yi-Rung" }, "orcid": "0000-0003-0331-3822" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Peterson-Elizabeth-A", "name": { "family": "Peterson", "given": "Elizabeth A." }, "orcid": "0000-0001-5379-3604" }, { "id": "Went-Cora-M", "name": { "family": "Went", "given": "Cora M." }, "orcid": "0000-0001-7737-3348" }, { "id": "Al-Balushi-Zakaria-Y", "name": { "family": "Al Balushi", "given": "Zakaria Y." }, "orcid": "0000-0003-0589-1618" }, { "id": "Jariwala-Deep", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Chen-Li-Chyong", "name": { "family": "Chen", "given": "Li-Chyong" }, "orcid": "0000-0001-6373-7729" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Band Edge Tailoring in Few-Layer Two-Dimensional Molybdenum Sulfide/Selenide Alloys", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: June 17, 2020; Revised: September 11, 2020; Published: September 14, 2020. \n\nThis work was performed in the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993. X-ray photoelectron spectroscopy was carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. Y.-R.L. acknowledges supports from the Ministry of Science and Technology (MoST), Taiwan. Y.-R.L. also acknowledges financial support by the Center of Atomic Initiative for New Materials, National Taiwan University, from the Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education in Taiwan (108L9008). \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - acs.jpcc.0c04719

Supplemental Material - jp0c04719_si_001.pdf

", "abstract": "Chemical alloying is a powerful approach to tune the electronic structure of semiconductors and has led to the synthesis of ternary and quaternary two-dimensional (2D) dichalcogenide semiconductor alloys (e.g., MoSSe\u2082, WSSe\u2082, etc.). To date, most of the studies have been focused on determining the chemical composition by evaluating the optical properties, primarily via photoluminescence and reflection spectroscopy of these materials in the 2D monolayer limit. However, a comprehensive study of alloying in multilayer films with direct measurement of electronic structure, combined with first-principles theory, is required for a complete understanding of this promising class of semiconductors. We have combined first-principles density functional theory calculations with experimental characterization of MoS_(2(1-x))Se_(2x) (where x ranges from 0 to 1) alloys using X-ray photoelectron spectroscopy to evaluate the valence and conduction band edge positions in each alloy. Moreover, our observations reveal that the valence band edge energies for molybdenum sulfide/selenide alloys increase as a function of increasing selenium concentration. These experimental results agree well with the results of density functional theory calculations showing a similar trend in calculated valence band edges. Our studies suggest that alloying is an effective technique for tuning the band edges of transition-metal dichalcogenides, with implications for applications such as solar cells and photoelectrochemical devices.", "date": "2020-10-22", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "124", "number": "42", "publisher": "American Chemical Society", "pagerange": "22893-22902", "id_number": "CaltechAUTHORS:20200914-111809687", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200914-111809687", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Ministry of Science and Technology (Taipei)" }, { "agency": "National Taiwan University" }, { "agency": "Ministry of Education (Taipei)", "grant_number": "108L9008" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.0c04719", "primary_object": { "basename": "acs.jpcc.0c04719", "url": "https://authors.library.caltech.edu/records/j02ha-dmz20/files/acs.jpcc.0c04719" }, "related_objects": [ { "basename": "jp0c04719_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j02ha-dmz20/files/jp0c04719_si_001.pdf" } ], "pub_year": "2020", "author_list": "Lin, Yi-Rung; Cheng, Wen-Hui; et al." }, { "id": "https://authors.library.caltech.edu/records/q92rt-vf471", "eprint_id": 105634, "eprint_status": "archive", "datestamp": "2023-08-19 23:55:17", "lastmod": "2023-10-20 22:12:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dong-Hai-T", "name": { "family": "Dong", "given": "Hai T." }, "orcid": "0000-0002-8914-3045" }, { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Zhao-Jiyong", "name": { "family": "Zhao", "given": "Jiyong" }, "orcid": "0000-0002-0777-3626" }, { "id": "Alp-Esen-Ercan", "name": { "family": "Alp", "given": "E. Ercan" }, "orcid": "0000-0002-4803-8863" }, { "id": "Hu-Michael-Y", "name": { "family": "Hu", "given": "Michael Y." }, "orcid": "0000-0002-3718-7169" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Lehnert-Nicolai", "name": { "family": "Lehnert", "given": "Nicolai" }, "orcid": "0000-0002-5221-5498" } ] }, "title": "Exploring the Limits of Dative Boratrane Bonding: Iron as a Strong Lewis Base in Low-Valent Non-Heme Iron-Nitrosyl Complexes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: June 8, 2020; Published: September 29, 2020. \n\nThis work was supported by grants from the National Science Foundation (CHE-1608331 and CHE-2002855 to NL) and the National Institutes of Health (GM 070757 to JCP). HTD acknowledges support from the Eastman Summer Research Fellowship and the Robert W. Parry Scholarship. MJC acknowledges support from the Resnick Sustainability Institute at Caltech. The Caltech EPR facility was supported by the Dow Next Generation Educator Fund. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1638627.pdf

Supplemental Material - ic0c01686_si_001.pdf

", "abstract": "We previously reported the synthesis and preliminary characterization of a unique series of low-spin (ls) {FeNO}\u2078\u207b\u00b9\u2070 complexes supported by an ambiphilic trisphosphineborane ligand, [Fe(TPB)(NO)]^(+/0/\u2212). Herein, we use advanced spectroscopic techniques and density functional theory (DFT) calculations to extract detailed information as to how the bonding changes across the redox series. We find that, in spite of the highly reduced nature of these complexes, they feature an NO+ ligand throughout with strong Fe\u2212NO \u03c0-backbonding and essentially closed-shell electronic structures of their FeNO units. This is enabled by an Fe\u2212B interaction that is present throughout the series. In particular, the most reduced [Fe(TPB)(NO)]\u2212 complex, an example of a ls-{FeNO}\u00b9\u2070 species, features a true reverse dative Fe \u2192 B bond where the Fe center acts as a strong Lewis-base. Hence, this complex is in fact electronically similar to the ls-{FeNO}\u2078 system, with two additional electrons \"stored\" on site in an Fe\u2212B single bond. The outlier in this series is the ls-{FeNO}\u2079 complex, due to spin polarization (quantified by pulse EPR spectroscopy), which weakens the Fe\u2212NO bond. These data are further contextualized by comparison with a related N\u2082 complex, [Fe(TPB)(N\u2082)]\u207b, which is a key intermediate in Fe(TPB)-catalyzed N\u2082 fixation. Our present study finds that the Fe \u2192 B interaction is key for storing the electrons needed to achieve a highly reduced state in these systems, and highlights the pitfalls associated with using geometric parameters to try to evaluate reverse dative interactions, a finding with broader implications to the study of transition metal complexes with boratrane and related ligands.", "date": "2020-10-19", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "59", "number": "20", "publisher": "American Chemical Society", "pagerange": "14967-14982", "id_number": "CaltechAUTHORS:20200929-105404784", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200929-105404784", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1608331" }, { "agency": "NSF", "grant_number": "CHE-2002855" }, { "agency": "NIH", "grant_number": "GM 070757" }, { "agency": "Eastman Summer Research Fellowship" }, { "agency": "Robert W. Parry Scholarship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.0c01686", "pmcid": "PMC7640944", "primary_object": { "basename": "ic0c01686_si_001.pdf", "url": "https://authors.library.caltech.edu/records/q92rt-vf471/files/ic0c01686_si_001.pdf" }, "related_objects": [ { "basename": "nihms-1638627.pdf", "url": "https://authors.library.caltech.edu/records/q92rt-vf471/files/nihms-1638627.pdf" } ], "pub_year": "2020", "author_list": "Dong, Hai T.; Chalkley, Matthew J.; et al." }, { "id": "https://authors.library.caltech.edu/records/gzzr8-65753", "eprint_id": 105842, "eprint_status": "archive", "datestamp": "2023-08-19 23:45:30", "lastmod": "2025-04-25 15:36:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dahlstrom-Kurt-M", "name": { "family": "Dahlstrom", "given": "Kurt M." }, "orcid": "0000-0001-6590-6020" }, { "id": "McRose-Darcy-L", "name": { "family": "McRose", "given": "Darcy L." }, "orcid": "0000-0001-9637-7176" }, { "id": "Newman-D-K", "name": { "family": "Newman", "given": "Dianne K." }, "orcid": "0000-0003-1647-1918" } ] }, "title": "Keystone metabolites of crop rhizosphere microbiomes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Elsevier Inc. \n\nAvailable online 5 October 2020. \n\nWe thank the following agencies and foundations for supporting our research: grants to D.K.N. from the ARO (W911NF-17-1-0024), NIH (1R01AI127850-01A1) and Caltech Resnick Sustainability Institute; the Life Sciences Research Foundation postdoctoral fellowship to K.M.D.; and the Caltech Biology & Biological Engineering Division and Simons Foundation Marine Microbial Ecology postdoctoral fellowships to D.L.M. We are grateful to A. Flamholz, D. Dar, L.S. Thomashow, L. Glass, C. Adams, and Z. Lonergan for insightful feedback on the manuscript. We also thank W.P. Falcon for helpful discussions about agriculture.\n\n

Accepted Version - nihms-1690209.pdf

", "abstract": "The role of microbes in sustaining agricultural plant growth has great potential consequences for human prosperity. Yet we have an incomplete understanding of the basic function of rhizosphere microbial communities and how they may change under future stresses, let alone how these processes might be harnessed to sustain or improve crop yields. A reductionist approach may aid the generation and testing of hypotheses that can ultimately be translated to agricultural practices. With this in mind, we ask whether some rhizosphere microbial communities might be governed by 'keystone metabolites', envisioned here as microbially produced molecules that, through antibiotic and/or growth-promoting properties, may play an outsized role in shaping the development of the community spatiotemporally. To illustrate this point, we use the example of redox-active metabolites, and in particular phenazines, which are produced by many bacteria found in agricultural soils and have well-understood catalytic properties. Phenazines can act as potent antibiotics against a variety of cell types, yet they also can promote the acquisition of essential inorganic nutrients. In this essay, we suggest the ways these metabolites might affect microbial communities and ultimately agricultural productivity in two specific scenarios: firstly, in the biocontrol of beneficial and pathogenic fungi in increasingly arid crop soils and, secondly, through promotion of phosphorus bioavailability and sustainable fertilizer use. We conclude with specific proposals for future research.", "date": "2020-10-05", "date_type": "published", "publication": "Current Biology", "volume": "30", "number": "19", "publisher": "Cell Press", "pagerange": "R1131-R1137", "id_number": "CaltechAUTHORS:20201006-131015350", "issn": "0960-9822", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201006-131015350", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0024" }, { "agency": "NIH", "grant_number": "1R01AI127850-01A1" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Life Sciences Research Foundation" }, { "agency": "Caltech Division of Biology and Biological Engineering" }, { "agency": "Simons Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1016/j.cub.2020.08.005", "pmcid": "PMC8059773", "primary_object": { "basename": "nihms-1690209.pdf", "url": "https://authors.library.caltech.edu/records/gzzr8-65753/files/nihms-1690209.pdf" }, "pub_year": "2020", "author_list": "Dahlstrom, Kurt M.; McRose, Darcy L.; et al." }, { "id": "https://authors.library.caltech.edu/records/0cyx0-8rq40", "eprint_id": 104974, "eprint_status": "archive", "datestamp": "2023-08-19 23:43:48", "lastmod": "2025-05-06 19:42:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Read-Carlos-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Dalleska-N-F", "name": { "family": "Dalleska", "given": "Nathan F." }, "orcid": "0000-0002-2059-1587" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Brinkert-Katharina", "name": { "family": "Brinkert", "given": "Katharina" }, "orcid": "0000-0002-3593-5047" } ] }, "title": "Cathodic NH\u2084\u207a leaching of nitrogen impurities in CoMo thin-film electrodes in aqueous acidic solutions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 01 May 2020; Accepted 05 Aug 2020; First published 05 Aug 2020. \n\nK. B. acknowledges funding from the fellowship program of the German National Academy of Sciences \u2013 Leopoldina, grant LPDS 2016-06. Acknowledgment is made to the donors of The American Chemical Society Petroleum Research Fund for partial support of this research. Sample preparation and analyses were performed at the Joint Center for Artificial Photosynthesis, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, which also provided support for N. S. L., W. Y., P. B. and C. G. R. We acknowledge use of instrumentation in the Molecular Materials Research Center of the Beckman Institute at Caltech. N. F. D. is grateful to the Linde Center for support. The Environmental Analysis Center is supported by the Beckman Institute at Caltech. W. Y. and C. G. R. acknowledge the Resnick Sustainability Institute at Caltech for fellowship support. Dr Fabai Wu and Prof. Victoria Orphan are acknowledged for providing the \u00b9\u2075NH\u2084Cl standard reagent for UPLC-MS analysis. Mr Christopher Kenseth is thanked for assistance with UPLC-MS analysis. Dr Yuanlong Huang is acknowledged for assistance with chemiluminescence analysis. All authors would like to acknowledge the reviewers for their valuable comments in the first round. \n\nThere are no conflicts to declare.\n\n

Supplemental Material - d0se00674b1.pdf

", "abstract": "Electrocatalytic reduction of dinitrogen (N\u2082) to ammonium (NH\u2084\u207a) in acidic aqueous solutions was investigated at ambient temperature and pressure using a cobalt\u2013molybdenum (CoMo) thin-film electrode prepared by magnetron reactive sputtering. Increased concentrations of ammonium ions (NH\u2084\u207a) were consistently detected in the electrolyte using ion chromatography (IC) after constant-potential electrolysis at various potentials (\u2264\u22120.29 V vs. RHE). Using a newly developed analytical method based on ammonia derivatization, performing the experiments with \u00b9\u2075N\u2082-labelled gas led however to the detection of increased \u00b9\u2074NH\u2084\u207a concentrations instead of \u00b9\u2075NH\u2084\u207a. X-ray photoelectron spectroscopic (XPS) analysis of the electrode surface revealed the presence of Mo N and Mo\u2013NH_x species. Several contamination sources were identified that led to substantial increases in the concentration of ammonium ions, including \u00b9\u2075NH\u2083 impurities in \u00b9\u2075N\u2082 gas. The observed ammonium concentrations can be consistently ascribed to leaching of nitrogen (\u00b9\u2074N) impurities incorporated in the CoMo film during the sputtering process. Researchers in the field are therefore urged to adopt extended protocols to identify and eliminate sources of ammonia contamination and to very carefully monitor the ammonium concentrations in each experimental step.", "date": "2020-10-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "4", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "5080-5087", "id_number": "CaltechAUTHORS:20200817-095314564", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200817-095314564", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Akademie der Naturforscher Leopoldina", "grant_number": "LPDS 2016-06" }, { "agency": "American Chemical Society Petroleum Research Fund" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d0se00674b", "primary_object": { "basename": "d0se00674b1.pdf", "url": "https://authors.library.caltech.edu/records/0cyx0-8rq40/files/d0se00674b1.pdf" }, "pub_year": "2020", "author_list": "Yu, Weilai; Buabthong, Pakpoom; et al." }, { "id": "https://authors.library.caltech.edu/records/fb56a-jst04", "eprint_id": 104233, "eprint_status": "archive", "datestamp": "2023-08-19 23:30:04", "lastmod": "2025-04-23 03:13:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hamann-Kathryn-R", "name": { "family": "Hamann", "given": "Kathryn R." }, "orcid": "0000-0003-1163-7173" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Thompson-Jonathan-R", "name": { "family": "Thompson", "given": "Jonathan R." } }, { "id": "Batara-Nicolas-A", "name": { "family": "Batara", "given": "Nicolas A." } }, { "id": "Yermolenko-Ian-S", "name": { "family": "Yermolenko", "given": "Ivan S." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Optically tunable mesoscale CdSe morphologies via inorganic phototropic growth", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 01 May 2020; Accepted 22 Jun 2020; First published\t22 Jun 2020. \n\nThis work was supported by the \"Light\u2013Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001293 and was also supported by the National Science Foundation, Directorate for Mathematical & Physical Sciences, Division of Materials Research under Award Number DMR 1905963. Research was in part carried out at the Molecular Materials Research Center in the Beckman Institute of Caltech. The authors gratefully acknowledge R. Gerhart for assistance with photoelectrochemical cell fabrication and W.-H. Cheng and M. Richter for assistance with computer simulations. KRH, AIC, and MCM acknowledge graduate research fellowships from the National Science Foundation. MCM also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nThere are no conflicts of interest to declare.\n\n

Supplemental Material - d0tc02126a1.pdf

", "abstract": "Inorganic phototropic growth using only spatially conformal illumination generated Se\u2013Cd films that exhibited precise light-defined mesoscale morphologies including highly ordered, anisotropic, and periodic ridge and trench nanotextures over entire macroscopic substrates. Growth was accomplished via a light-induced electrochemical method using an optically and chemically isotropic solution, an unpatterned substrate, and unstructured, incoherent, low-intensity illumination in the absence of chemical directing agents or physical templates and masks. The morphologies were defined by the illumination inputs: the nanotexture long axes aligned parallel to the optical E-field vector, and the feature sizes and periods scaled with the wavelength. Optically based modeling of the growth closely reproduced the experimental results, confirming the film morphologies were fully determined by the light\u2013matter interactions during growth. Solution processing of the Se\u2013Cd films resulted in stoichiometric, crystalline CdSe films that also exhibited ordered nanotextures, demonstrating that inorganic phototropic growth can effect tunable, template-free generation of ordered CdSe nanostructures over macroscopic length scales.", "date": "2020-09-28", "date_type": "published", "publication": "Journal of Materials Chemistry C", "volume": "8", "number": "36", "publisher": "Royal Society of Chemistry", "pagerange": "12412-12417", "id_number": "CaltechAUTHORS:20200706-150753170", "issn": "2050-7526", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200706-150753170", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "NSF", "grant_number": "DMR-1905963" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d0tc02126a", "primary_object": { "basename": "d0tc02126a1.pdf", "url": "https://authors.library.caltech.edu/records/fb56a-jst04/files/d0tc02126a1.pdf" }, "pub_year": "2020", "author_list": "Hamann, Kathryn R.; Carim, Azhar I.; et al." }, { "id": "https://authors.library.caltech.edu/records/q4n3y-8tm47", "eprint_id": 102655, "eprint_status": "archive", "datestamp": "2023-08-19 23:28:31", "lastmod": "2023-10-20 00:23:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jhalani-V-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" }, "orcid": "0000-0002-1763-5788" }, { "id": "Dreyer-C-E", "name": { "family": "Dreyer", "given": "Cyrus E." } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Piezoelectric Electron-Phonon Interaction from Ab Initio Dynamical Quadrupoles: Impact on Charge Transport in Wurtzite GaN", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Physical Society. \n\nReceived 20 February 2020; accepted 27 August 2020; published 21 September 2020. \n\nV.\u2009J. thanks the Resnick Sustainability Institute at Caltech for fellowship support. J.\u2009P. acknowledges support by the Korea Foundation for Advanced Studies. This work was supported by the National Science Foundation under Grants No. DMR-1750613 for theory development and No. ACI-1642443 for code development. J.-J.\u2009Z. acknowledges partial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of some computational methods employed in this work was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. C.\u2009E.\u2009D. acknowledges support from the National Science Foundation under Grant No. DMR-1918455. The Flatiron Institute is a division of the Simons Foundation. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\n

Published - PhysRevLett.125.136602.pdf

Submitted - 2002.08351.pdf

Supplemental Material - SuppInfo.pdf

", "abstract": "First-principles calculations of e\u2212ph interactions are becoming a pillar of electronic structure theory. However, the current approach is incomplete. The piezoelectric (PE) e\u2212ph interaction, a long-range scattering mechanism due to acoustic phonons in noncentrosymmetric polar materials, is not accurately described at present. Current calculations include short-range e\u2212ph interactions (obtained by interpolation) and the dipolelike Fr\u00f6lich long-range coupling in polar materials, but lack important quadrupole effects for acoustic modes and PE materials. Here we derive and compute the long-range e\u2212ph interaction due to dynamical quadrupoles, and apply this framework to investigate e\u2212ph interactions and the carrier mobility in the PE material wurtzite GaN. We show that the quadrupole contribution is essential to obtain accurate e\u2212ph matrix elements for acoustic modes and to compute PE scattering. Our work resolves the outstanding problem of correctly computing e\u2212ph interactions for acoustic modes from first principles, and enables studies of e\u2212ph coupling and charge transport in PE materials.", "date": "2020-09-25", "date_type": "published", "publication": "Physical Review Letters", "volume": "125", "number": "13", "publisher": "American Physical Society", "pagerange": "Art. No. 136602", "id_number": "CaltechAUTHORS:20200420-112051827", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200420-112051827", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-1918455" }, { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevLett.125.136602", "primary_object": { "basename": "2002.08351.pdf", "url": "https://authors.library.caltech.edu/records/q4n3y-8tm47/files/2002.08351.pdf" }, "related_objects": [ { "basename": "PhysRevLett.125.136602.pdf", "url": "https://authors.library.caltech.edu/records/q4n3y-8tm47/files/PhysRevLett.125.136602.pdf" }, { "basename": "SuppInfo.pdf", "url": "https://authors.library.caltech.edu/records/q4n3y-8tm47/files/SuppInfo.pdf" } ], "pub_year": "2020", "author_list": "Jhalani, Vatsal A.; Zhou, Jin-Jian; et al." }, { "id": "https://authors.library.caltech.edu/records/e62n6-sva42", "eprint_id": 105197, "eprint_status": "archive", "datestamp": "2023-08-19 23:26:21", "lastmod": "2023-10-20 21:27:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chapovetsky-A", "name": { "family": "Chapovetsky", "given": "Alon" }, "orcid": "0000-0001-8095-8830" }, { "id": "Liu-Jeffrey-J", "name": { "family": "Liu", "given": "Jeffrey J." }, "orcid": "0000-0003-2147-6449" }, { "id": "Welborn-M", "name": { "family": "Welborn", "given": "Matthew" } }, { "id": "Luna-J-M", "name": { "family": "Luna", "given": "John M." } }, { "id": "Do-Thomas", "name": { "family": "Do", "given": "Thomas" } }, { "id": "Haiges-R", "name": { "family": "Haiges", "given": "Ralf" }, "orcid": "0000-0003-4151-3593" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Marinescu-S-C", "name": { "family": "Marinescu", "given": "Smaranda C." }, "orcid": "0000-0003-2106-8971" } ] }, "title": "Electronically Modified Cobalt Aminopyridine Complexes Reveal an Orthogonal Axis for Catalytic Optimization for CO\u2082 Reduction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: July 14, 2020; Published: August 31, 2020. \n\nThe research was primarily supported by the National Science Foundation (NSF) under the CAREER Award CHE-1555387 (experimental studies) and the Chemistry of Life Processes Program CHE-1611581 (theoretical studies). S.C.M. acknowledges additional support from the Alfred P. Sloan Foundation through a Sloan research fellowship, the University of Southern California (USC), and the USC Women in Science and Engineering program. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the DOE Office of Science under contract DE-AC02-05CH11231. M.W. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. We thank Alfred Sattelberger for helpful discussions. \n\nAccession Codes: CCDC 2016095\u20132016096 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44 1223 336033. \n\nAuthor Contributions: The manuscript was written through contributions of all authors. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ic0c02086_si_001.pdf

", "abstract": "The design of effective electrocatalysts for carbon dioxide reduction requires understanding the mechanistic underpinnings governing the binding, reduction, and protonation of CO\u2082. A critical aspect to understanding and tuning these factors for optimal catalysis revolves around controlling the electronic environments of the primary and secondary coordination sphere. Herein we report a series of para-substituted cobalt aminopyridine macrocyclic catalysts 2\u20134 capable of carrying out the electrochemical reduction of CO\u2082 to CO. Under catalytic conditions, complexes 2\u20134, as well as the unsubstituted cobalt aminopyridine complex 1, exhibit i_(cat)/i_p values ranging from 144 to 781. Complexes 2 and 4 exhibit a pronounced precatalytic wave suggestive of an ECEC mechanism. A Hammett analysis reveals that ligand modifications with electron-donating groups enhance catalysis (\u03c1 < 0), indicative of positive charge buildup in the transition state. This trend also extends to the Co^(I/0) potential, where complexes possessing more negative E(CoI/0) reductions exhibit greater i_(cat)/i_p values. The reported modifications offer a synthetic lever to tune catalytic activity, orthogonal to our previous study of the role of pendant hydrogen bond donors.", "date": "2020-09-21", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "59", "number": "18", "publisher": "American Chemical Society", "pagerange": "13709-13718", "id_number": "CaltechAUTHORS:20200901-095615539", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200901-095615539", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1555387" }, { "agency": "NSF", "grant_number": "CHE-1611581" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "University of Southern California" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.0c02086", "primary_object": { "basename": "ic0c02086_si_001.pdf", "url": "https://authors.library.caltech.edu/records/e62n6-sva42/files/ic0c02086_si_001.pdf" }, "pub_year": "2020", "author_list": "Chapovetsky, Alon; Liu, Jeffrey J.; et al." }, { "id": "https://authors.library.caltech.edu/records/xyz2a-9v642", "eprint_id": 105445, "eprint_status": "archive", "datestamp": "2023-08-19 23:24:45", "lastmod": "2023-10-20 22:00:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wu-Wenbo", "name": { "family": "Wu", "given": "Wenbo" }, "orcid": "0000-0002-6249-8065" }, { "id": "Zhan-Zhongwen", "name": { "family": "Zhan", "given": "Zhongwen" }, "orcid": "0000-0002-5586-2607" }, { "id": "Peng-Shirui", "name": { "family": "Peng", "given": "Shirui" }, "orcid": "0000-0002-4616-4604" }, { "id": "Ni-Sidao", "name": { "family": "Ni", "given": "Sidao" }, "orcid": "0000-0003-2988-4850" }, { "id": "Callies-J", "name": { "family": "Callies", "given": "J\u00f6rn" }, "orcid": "0000-0002-6815-1230" } ] }, "title": "Seismic ocean thermometry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Association for the Advancement of Science.\nThis is an article distributed under the terms of the Science Journals Default License. \n\nReceived 28 March 2020; accepted 31 July 2020. \n\nThis work was supported in part by the Caltech Seismological Laboratory Director's Postdoctoral Scholar fellowship awarded to W.W. and by the Resnick Sustainability Institute. S.N. was supported by the National Natural Science Foundation of China (grant 41590854) and the Chinese Academy of Sciences (grant XDB18000000). \n\nAuthor contributions: W.W. conceived the original idea. Z.Z. and J.C. supervised the study. W.W. processed the seismic data and conducted the seismic modeling. S.P. and J.C. processed the oceanographic data, and J.C. performed the data inversion. The paper was written by W.W. and J.C. with input from Z.Z. and S.N. All authors discussed the results and commented on the manuscript. \n\nThe authors declare no competing interests. \n\nData and materials availability: The seismic data are archived at the Incorporated Research Institutions for Seismology (IRIS) and are accessible through the IRIS Data Management Center (http://ds.iris.edu/). ECCO data are available from NASA's Data Portal (https://data.nas.nasa.gov/). Argo data are collected and made freely available by the International Argo Program and the national programs that contribute to it. The float data are available from the Global Data Assembly Centre (41). The figures were prepared using the Generic Mapping Tools (www.soest.hawaii.edu/gmt/), Obspy (https://github.com/obspy/obspy), Cartopy (https://scitools.org.uk/cartopy/), and Matplotlib (https://matplotlib.org/).\n\n

Supplemental Material - abb9519_Wu_SM.pdf

", "abstract": "More than 90% of the energy trapped on Earth by increasingly abundant greenhouse gases is absorbed by the ocean. Monitoring the resulting ocean warming remains a challenging sampling problem. To complement existing point measurements, we introduce a method that infers basin-scale deep-ocean temperature changes from the travel times of sound waves that are generated by repeating earthquakes. A first implementation of this seismic ocean thermometry constrains temperature anomalies averaged across a 3000-kilometer-long section in the equatorial East Indian Ocean with a standard error of 0.0060 kelvin. Between 2005 and 2016, we find temperature fluctuations on time scales of 12 months, 6 months, and ~10 days, and we infer a decadal warming trend that substantially exceeds previous estimates.", "date": "2020-09-18", "date_type": "published", "publication": "Science", "volume": "369", "number": "6510", "publisher": "American Association for the Advancement of Science", "pagerange": "1510-1515", "id_number": "CaltechAUTHORS:20200918-085145090", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200918-085145090", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Seismological Laboratory" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41590854" }, { "agency": "Chinese Academy of Sciences", "grant_number": "XDB18000000" } ] }, "local_group": { "items": [ { "id": "Seismological-Laboratory" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.abb9519", "primary_object": { "basename": "abb9519_Wu_SM.pdf", "url": "https://authors.library.caltech.edu/records/xyz2a-9v642/files/abb9519_Wu_SM.pdf" }, "pub_year": "2020", "author_list": "Wu, Wenbo; Zhan, Zhongwen; et al." }, { "id": "https://authors.library.caltech.edu/records/9djjb-yxd48", "eprint_id": 104772, "eprint_status": "archive", "datestamp": "2023-08-22 06:24:59", "lastmod": "2023-10-20 20:49:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dowling-Jacqueline-A", "name": { "family": "Dowling", "given": "Jacqueline A." }, "orcid": "0000-0001-5642-8960" }, { "id": "Rinaldi-Katherine-Z", "name": { "family": "Rinaldi", "given": "Katherine Z." }, "orcid": "0000-0002-0746-2852" }, { "id": "Ruggles-Tyler-H", "name": { "family": "Ruggles", "given": "Tyler H." }, "orcid": "0000-0002-6643-2047" }, { "id": "Davis-Steven-J", "name": { "family": "Davis", "given": "Steven J." }, "orcid": "0000-0002-9338-0844" }, { "id": "Yuan-Mengyao", "name": { "family": "Yuan", "given": "Mengyao" }, "orcid": "0000-0002-5923-4085" }, { "id": "Tong-Fan", "name": { "family": "Tong", "given": "Fan" }, "orcid": "0000-0003-4661-3956" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Caldeira-Ken", "name": { "family": "Caldeira", "given": "Ken" }, "orcid": "0000-0002-4591-643X" } ] }, "title": "Role of Long-Duration Energy Storage in Variable Renewable Electricity Systems", "ispublished": "pub", "full_text_status": "public", "keywords": "long-duration energy storage; renewable energy; zero-carbon electricity; electricity cost; macro-energy model; wind energy; solar energy; batteries; storage technologies; long-term energy storage", "note": "\u00a9 2020 Elsevier Inc. \n\nReceived 14 May 2020, Revised 21 May 2020, Accepted 9 July 2020, Available online 6 August 2020. \n\nJ.A.D. acknowledges fellowship support from the Resnick Sustainability Institute at Caltech. This work was also supported by the Gordon and Betty Moore Foundation, a fellowship from SoCalGas in support of Low Carbon Energy Science and Policy, and a gift from Gates Ventures LLC to the Carnegie Institution for Science. The authors thank Lei Duan, and David Farnham for providing wind, solar, and demand input data. J.A.D. thanks Eric Ewing for technical assistance during manuscript preparation. \n\nAuthor Contributions: N.S.L. and K.C. conceived this study. J.A.D., K.C., and N.S.L. designed the analyses with contributions from K.Z.R., T.H.R., M.Y., and F.T. K.C., F.T., M.Y., and J.A.D. developed and tested the version of the model used in this study. K.Z.R. assisted with literature review, T.H.R. compiled various technology costs, and S.J.D. improved the figures and main text. J.A.D. performed the analyses and wrote the manuscript with interactive feedback from N.S.L., K.C., K.Z.R., T.H.R., S.J.D., M.Y., and F.T. All authors edited the manuscript and provided helpful discussions. \n\nThe authors declare no competing interests.\n\n

Supplemental Material - 1-s2.0-S2542435120303251-mmc1.pdf

", "abstract": "Reliable and affordable electricity systems based on variable energy sources, such as wind and solar may depend on the ability to store large quantities of low-cost energy over long timescales. Here, we use 39 years of hourly U.S. weather data, and a macro-scale energy model to evaluate capacities and dispatch in least cost, 100% reliable electricity systems with wind and solar generation supported by long-duration storage (LDS; 10 h or greater) and battery storage. We find that the introduction of LDS lowers total system costs relative to wind-solar-battery systems, and that system costs are twice as sensitive to reductions in LDS costs as to reductions in battery costs. In least-cost systems, batteries are used primarily for intra-day storage and LDS is used primarily for inter-season and multi-year storage. Moreover, dependence on LDS increases when the system is optimized over more years. LDS technologies could improve the affordability of renewable electricity.", "date": "2020-09-16", "date_type": "published", "publication": "Joule", "volume": "4", "number": "9", "publisher": "Cell Press", "pagerange": "1907-1928", "id_number": "CaltechAUTHORS:20200806-090232377", "issn": "2542-4351", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200806-090232377", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Southern California Gas Company" }, { "agency": "Gates Ventures LLC" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.joule.2020.07.007", "primary_object": { "basename": "1-s2.0-S2542435120303251-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/9djjb-yxd48/files/1-s2.0-S2542435120303251-mmc1.pdf" }, "pub_year": "2020", "author_list": "Dowling, Jacqueline A.; Rinaldi, Katherine Z.; et al." }, { "id": "https://authors.library.caltech.edu/records/eg0bd-gsc78", "eprint_id": 103291, "eprint_status": "archive", "datestamp": "2023-08-19 23:21:45", "lastmod": "2023-10-20 15:52:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" }, "orcid": "0000-0002-1763-5788" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Jhalani-V-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Dreyer-C-E", "name": { "family": "Dreyer", "given": "Cyrus E." } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Long-range quadrupole electron-phonon interaction from first principles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Physical Society. \n\nReceived 30 March 2020; accepted 29 May 2020; published 21 September 2020. \n\nJ.P. acknowledges support by the Korea Foundation for Advanced Studies. V.A.J. thanks the Resnick Sustainability Institute at Caltech for fellowship support. This work was supported by the National Science Foundation under Grants No. DMR-1750613 for theory development and No. ACI-1642443 for code development. J.-J.Z. acknowledges partial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of some computational methods employed in this work was supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993. C.E.D. acknowledges support from the National Science Foundation under Grant No. DMR-1918455. The Flatiron Institute is a division of the Simons Foundation. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231.\n\n

Published - PhysRevB.102.125203.pdf

Submitted - 2003.13782.pdf

", "abstract": "Lattice vibrations in materials induce perturbations on the electron dynamics in the form of long-range (dipole and quadrupole) and short-range (octopole and higher) potentials. The dipole Fr\u00f6hlich term can be included in current first-principles electron-phonon (e-ph) calculations and is present only in polar materials. The quadrupole e-ph interaction is present in both polar and nonpolar materials, but currently it cannot be computed from first principles. Here we show an approach to compute the quadrupole e-ph interaction and include it in ab initio calculations of e-ph matrix elements. The accuracy of the approach is demonstrated by comparing with direct density functional perturbation theory calculations. We apply our method to silicon as a case of a nonpolar semiconductor and tetragonal PbTiO\u2083 as a case of a polar piezoelectric material. In both materials we find that the quadrupole term strongly impacts the e-ph matrix elements. Analysis of e-ph interactions for different phonon modes reveals that the quadrupole term mainly affects optical modes in silicon and acoustic modes in PbTiO\u2083, although the quadrupole term is needed for all modes to achieve quantitative accuracy. The effect of the quadrupole e-ph interaction on electron scattering processes and transport is shown to be important. Our approach enables accurate studies of e-ph interactions in broad classes of nonpolar, polar, and piezoelectric materials.", "date": "2020-09-15", "date_type": "published", "publication": "Physical Review B", "volume": "102", "number": "12", "publisher": "American Physical Society", "pagerange": "Art. No. 125203", "id_number": "CaltechAUTHORS:20200518-152636389", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200518-152636389", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-1918455" }, { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.102.125203", "primary_object": { "basename": "2003.13782.pdf", "url": "https://authors.library.caltech.edu/records/eg0bd-gsc78/files/2003.13782.pdf" }, "related_objects": [ { "basename": "PhysRevB.102.125203.pdf", "url": "https://authors.library.caltech.edu/records/eg0bd-gsc78/files/PhysRevB.102.125203.pdf" } ], "pub_year": "2020", "author_list": "Park, Jinsoo; Zhou, Jin-Jian; et al." }, { "id": "https://authors.library.caltech.edu/records/fy6f4-9fb09", "eprint_id": 105044, "eprint_status": "archive", "datestamp": "2023-08-22 06:16:03", "lastmod": "2023-10-23 17:21:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cohen-Yair", "name": { "family": "Cohen", "given": "Yair" }, "orcid": "0000-0002-9615-2476" }, { "id": "Lopez\u2010Gomez-Ignacio", "name": { "family": "Lopez\u2010Gomez", "given": "Ignacio" }, "orcid": "0000-0002-7255-5895" }, { "id": "Jaruga-Anna", "name": { "family": "Jaruga", "given": "Anna" }, "orcid": "0000-0003-3194-6440" }, { "id": "He-Jia", "name": { "family": "He", "given": "Jia" } }, { "id": "Kaul-Colleen-M", "name": { "family": "Kaul", "given": "Colleen M." }, "orcid": "0000-0002-4462-0987" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "Tapio" }, "orcid": "0000-0001-5687-2287" } ] }, "title": "Unified Entrainment and Detrainment Closures for Extended Eddy-Diffusivity Mass-Flux Schemes", "ispublished": "pub", "full_text_status": "public", "keywords": "Unified parameterization; Convective parameterization; Eddy\u2010Diffusivity Mass\u2010Flux parameterization; Entrainment and Detrainment; Deep convection; Climate modeling", "note": "\u00a9 2020 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 14 September 2020; Version of Record online: 14 September 2020; Accepted manuscript online: 04 August 2020; Manuscript accepted: 29 July 2020; Manuscript revised: 09 July 2020; Manuscript received: 01 May 2020. \n\nThis research was made possible by the generosity of Eric and Wendy Schmidt by recommendation of the Schmidt Futures program, by Earthrise Alliance, Mountain Philanthropies, the Paul G. Allen Family Foundation, and the National Science Foundation (NSF, Award AGS\u20101835860). I. L. would like to thank the Resnick Sustainability Institute at Caltech for fellowship support. Parts of the research were carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004) and funded through the internal Research and Technology Development program. The comments provided by Nadir Jeevanjee and one more anonymous reviewer greatly improved the final form of this work. \u00a9 2020. California Institute of Technology. Government sponsorship acknowledged. \n\nData Availability Statements: The PyCLES code used to generate LES results is available at this site (climate-dynamics.org/software/#pycles). The SCM code is available at this site (https://doi.org/10.5281/zenodo.3789011).\n\n

Published - 2020MS002162.pdf

Submitted - essoar.10502905.1.pdf

Supplemental Material - jame21196-sup-0001-2020ms002162-si.tex

", "abstract": "We demonstrate that an extended eddy\u2010diffusivity mass\u2010flux (EDMF) scheme can be used as a unified parameterization of subgrid\u2010scale turbulence and convection across a range of dynamical regimes, from dry convective boundary layers, through shallow convection, to deep convection. Central to achieving this unified representation of subgrid\u2010scale motions are entrainment and detrainment closures. We model entrainment and detrainment rates as a combination of turbulent and dynamical processes. Turbulent entrainment/detrainment is represented as downgradient diffusion between plumes and their environment. Dynamical entrainment/detrainment is proportional to a ratio of a relative buoyancy of a plume and a vertical velocity scale, that is modulated by heuristic nondimensional functions which represent their relative magnitudes and the enhanced detrainment due to evaporation from clouds in drier environment. We first evaluate the closures off\u2010line against entrainment and detrainment rates diagnosed from large eddy simulations (LESs) in which tracers are used to identify plumes, their turbulent environment, and mass and tracer exchanges between them. The LES are of canonical test cases of a dry convective boundary layer, shallow convection, and deep convection, thus spanning a broad rangeof regimes. We then compare the LES with the full EDMF scheme, including the new closures, in a single\u2010column model (SCM). The results show good agreement between the SCM and LES in quantities that are key for climate models, including thermodynamic profiles, cloud liquid water profiles, and profiles of higher moments of turbulent statistics. The SCM also captures well the diurnal cycle of convection and the onset of precipitation.", "date": "2020-09", "date_type": "published", "publication": "Journal of Advances in Modeling Earth Systems", "volume": "12", "number": "9", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020MS002162", "id_number": "CaltechAUTHORS:20200820-123726127", "issn": "1942-2466", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200820-123726127", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Eric and Wendy Schmidt" }, { "agency": "Schmidt Futures Program" }, { "agency": "Earthrise Alliance" }, { "agency": "Mountain Philanthropies" }, { "agency": "Paul G. Allen Family Foundation" }, { "agency": "NSF", "grant_number": "AGS-1835860" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "80NM0018D0004" }, { "agency": "JPL Internal Research and Technology Development Program" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020ms002162", "primary_object": { "basename": "2020MS002162.pdf", "url": "https://authors.library.caltech.edu/records/fy6f4-9fb09/files/2020MS002162.pdf" }, "related_objects": [ { "basename": "essoar.10502905.1.pdf", "url": "https://authors.library.caltech.edu/records/fy6f4-9fb09/files/essoar.10502905.1.pdf" }, { "basename": "jame21196-sup-0001-2020ms002162-si.tex", "url": "https://authors.library.caltech.edu/records/fy6f4-9fb09/files/jame21196-sup-0001-2020ms002162-si.tex" } ], "pub_year": "2020", "author_list": "Cohen, Yair; Lopez\u2010Gomez, Ignacio; et al." }, { "id": "https://authors.library.caltech.edu/records/ejf32-awn80", "eprint_id": 105016, "eprint_status": "archive", "datestamp": "2023-08-19 22:57:06", "lastmod": "2023-10-20 21:17:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chalkley-M-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Garrido-Barros-P", "name": { "family": "Garrido-Barros", "given": "Pablo" }, "orcid": "0000-0002-1489-3386" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "A molecular mediator for reductive concerted proton-electron transfers via electrocatalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Association for the Advancement of Science.\nThis is an article distributed under the terms of the Science Journals Default License. \n\nReceived 9 April 2020; accepted 24 June 2020. \n\nWe thank the Dow Next Generation Educator Funds and Instrumentation Grants for their support of the NMR facility at Caltech and the X-ray Crystallography Facility in the Beckman Institute at Caltech. We also thank the Molecular Materials Research Center in the Beckman Institute at Caltech for use of the x-ray photoelectron spectrometer. \n\nThis study was supported by funding from the U.S. Department of Energy (DOE-0235032). M.J.C. thanks the Resnick Sustainability Institute for a graduate fellowship, and P.G.-B. thanks the Ram\u00f3n Areces Foundation for a postdoctoral fellowship. \n\nAuthor contributions: M.J.C. and P.G.-B. designed and executed experiments, and all authors analyzed and interpreted data and cowrote the manuscript. \n\nThe authors declare no competing interests. \n\nData and materials availability: X-ray structural data are available free of charge from the Cambridge Structural Database under CCDC 1985828 to 1985830. All other data are available in the main text or supplementary materials.\n\n

Supplemental Material - abc1607_Chalkley_SM.pdf

", "abstract": "Electrocatalytic approaches to the activation of unsaturated substrates via reductive concerted proton-electron transfer (CPET) must overcome competing, often kinetically dominant hydrogen evolution. We introduce the design of a molecular mediator for electrochemically triggered reductive CPET through the synthetic integration of a Br\u00f8nsted acid and a redox mediator. Cathodic reduction at the cobaltocenium redox mediator substantially weakens the homolytic nitrogen-hydrogen bond strength of a Br\u00f8nsted acidic anilinium tethered to one of the cyclopentadienyl rings. The electrochemically generated molecular mediator is demonstrated to transform a model substrate, acetophenone, to its corresponding neutral \u03b1-radical via a rate-determining CPET.", "date": "2020-08-14", "date_type": "published", "publication": "Science", "volume": "369", "number": "6505", "publisher": "American Association for the Advancement of Science", "pagerange": "850-854", "id_number": "CaltechAUTHORS:20200818-151407945", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200818-151407945", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Ram\u00f3n Areces Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/science.abc1607", "primary_object": { "basename": "abc1607_Chalkley_SM.pdf", "url": "https://authors.library.caltech.edu/records/ejf32-awn80/files/abc1607_Chalkley_SM.pdf" }, "pub_year": "2020", "author_list": "Chalkley, Matthew J.; Garrido-Barros, Pablo; et al." }, { "id": "https://authors.library.caltech.edu/records/zfspq-qva07", "eprint_id": 104347, "eprint_status": "archive", "datestamp": "2023-08-19 22:33:52", "lastmod": "2023-10-20 22:24:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stauber-Julia-M", "name": { "family": "Stauber", "given": "Julia M." }, "orcid": "0000-0001-9783-907X" }, { "id": "Schwan-Josef", "name": { "family": "Schwan", "given": "Josef" }, "orcid": "0000-0002-1086-6698" }, { "id": "Zhang-Xinglong", "name": { "family": "Zhang", "given": "Xinglong" }, "orcid": "0000-0003-1698-692X" }, { "id": "Axtell-Jonathan-C", "name": { "family": "Axtell", "given": "Jonathan C." }, "orcid": "0000-0002-5579-4296" }, { "id": "Jung-Dahee", "name": { "family": "Jung", "given": "Dahee" }, "orcid": "0000-0003-1863-0193" }, { "id": "McNicholas-Brendon-J", "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Martinolich-Andrew-J", "name": { "family": "Martinolich", "given": "Andrew J." }, "orcid": "0000-0002-7866-9594" }, { "id": "Winkler-Jay-R", "name": { "family": "Winkler", "given": "Jay R." }, "orcid": "0000-0002-4453-9716" }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Spokoyny-Alexander-M", "name": { "family": "Spokoyny", "given": "Alexander M." }, "orcid": "0000-0002-5683-6240" } ] }, "title": "A Super-Oxidized Radical Cationic Icosahedral Boron Cluster", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: June 8, 2020; Published: July 10, 2020. \n\nThis work was supported as part of the Center for Synthetic Control Across Length-scales for Advancing Rechargeables (SCALAR), an Energy Frontier Research Center funded by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES) under Award No. DE-SC0019381 (A.M.S. and K.A.S. synthesis and characterization; T.F.M., computational work and theory). A.M.S. is a Research Corporation for Science Advancement (RCSA) Cottrell Scholar and a Dreyfus Foundation Camille Dreyfus Teacher-Scholar. Acknowledgment is made to the donors of The American Chemical Society Petroleum Research Fund for funding work in the H.B.G. lab (J.S. and H.B.G.). Work in the Beckman Institute at Caltech was supported by the Arnold and Mabel Beckman Foundation (B.J.M., J.R.W.). X.Z. acknowledges the Agency for Science, Technology and Research (Singapore) for an A*STAR fellowship. X.Z. and T.F.M. acknowledge the computational resources from the Extreme Science and Engineering Discovery Environment (XSEDE) Bridges computer at the Pittsburgh Supercomputing Center through allocation TG-MCB160013. A.J.M. acknowledges support through a postdoctoral fellowship from the Resnick Sustainability Institute at Caltech. D.J. acknowledges the UCLA Graduate Division for the Dissertation Year Fellowship. The National Science Foundation (NSF-1531940) and the Dow Next Generation Educator Fund are acknowledged for EPR facility support. \n\nThe authors declare the following competing financial interest(s): UCLA has patents on several compounds reported in this work from which A.M.S. and current/former co-workers may receive royalty payments. The Cs\u2082[B\u2081\u2082(OH)\u2081\u2082] salt (Catalog #902209) is commercially available through the MilliporeSigma catalog.\n\n

Submitted - a-super-oxidized-radical-cationic-icosahedral-boron-cluster.pdf

Supplemental Material - ja0c06159_si_001.pdf

", "abstract": "While the icosahedral closo-[B\u2081\u2082H\u2081\u2082]\u00b2\u207b cluster does not display reversible electrochemical behavior, perfunctionalization of this species via substitution of all 12 B\u2013H vertices with alkoxy or benzyloxy (OR) substituents engenders reversible redox chemistry, providing access to clusters in the dianionic, monoanionic, and neutral forms. Here, we evaluated the electrochemical behavior of the electron-rich B\u2081\u2082(O-3-methylbutyl)\u2081\u2082 (1) cluster and discovered that a new reversible redox event that gives rise to a fourth electronic state is accessible through one-electron oxidation of the neutral species. Chemical oxidation of 1 with [N(2,4-Br\u2082C\u2086H\u2083)\u2083]\u00b7\u207a afforded the isolable [1]\u00b7\u207a cluster, which is the first example of an open-shell cationic B\u2081\u2082 cluster in which the unpaired electron is proposed to be delocalized throughout the boron cluster core. The oxidation of 1 is also chemically reversible, where treatment of [1]\u00b7\u207a with ferrocene resulted in its reduction back to 1. The identity of [1]\u00b7\u207a is supported by EPR, UV\u2013vis, multinuclear NMR (\u00b9H, \u00b9\u00b9B), and X-ray photoelectron spectroscopic characterization.", "date": "2020-07-29", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "142", "number": "30", "publisher": "American Chemical Society", "pagerange": "12948-12953", "id_number": "CaltechAUTHORS:20200713-085326752", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200713-085326752", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019381" }, { "agency": "Cottrell Scholar of Research Corporation" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "American Chemical Society Petroleum Research Fund" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Agency for Science, Technology and Research (A*STAR)" }, { "agency": "NSF", "grant_number": "TG-MCB160013" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "UCLA" }, { "agency": "NSF", "grant_number": "CHE-1531940" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.0c06159", "primary_object": { "basename": "a-super-oxidized-radical-cationic-icosahedral-boron-cluster.pdf", "url": "https://authors.library.caltech.edu/records/zfspq-qva07/files/a-super-oxidized-radical-cationic-icosahedral-boron-cluster.pdf" }, "related_objects": [ { "basename": "ja0c06159_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zfspq-qva07/files/ja0c06159_si_001.pdf" } ], "pub_year": "2020", "author_list": "Stauber, Julia M.; Schwan, Josef; et al." }, { "id": "https://authors.library.caltech.edu/records/2k595-pes34", "eprint_id": 104373, "eprint_status": "archive", "datestamp": "2023-08-22 05:43:06", "lastmod": "2023-10-20 19:21:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chadwick-A-J", "name": { "family": "Chadwick", "given": "Austin J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" }, { "id": "Ganti-V", "name": { "family": "Ganti", "given": "Vamsi" }, "orcid": "0000-0003-2165-6052" } ] }, "title": "Accelerated river avulsion frequency on lowland deltas due to sea-level rise", "ispublished": "pub", "full_text_status": "public", "keywords": "sea-level rise; river deltas; river avulsion", "note": "\u00a9 2020 National Academy of Sciences. Published under the PNAS license. \n\nEdited by Andrea Rinaldo, \u00c9cole Polytechnique F\u00e9d\u00e9rale de Lausanne, Lausanne, Switzerland, and approved June 3, 2020 (received for review July 17, 2019). PNAS first published July 13, 2020. \n\nWe thank Andrew Moodie, Gary Parker, Jeffrey Nittrouer, Hongbo Ma, and Brad Murray for useful discussions and three reviewers for constructive comments. We acknowledge NSF Grant EAR 1427262 and the Resnick Sustainability Institute at the California Institute of Technology for support. \n\nAuthor contributions: A.J.C., M.P.L., and V.G. designed research; A.J.C. and M.P.L. performed research; A.J.C. and M.P.L. analyzed data; and A.J.C., M.P.L., and V.G. wrote the paper. \n\nThe authors declare no competing interest. \n\nThis article is a PNAS Direct Submission. \n\nData deposition: The data and model code underlying this study are publicly available in the SEAD Repository (http://doi.org/10.26009/s0FSLKFK) and GitHub (https://github.com/achadwick2323/Accelerated-river-avulsion-frequency-on-lowland-deltas-due-to-sea-level-rise), respectively. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.1912351117/-/DCSupplemental.\n\n

Published - 17584.full.pdf

Supplemental Material - pnas.1912351117.sapp.pdf

", "abstract": "Sea-level rise, subsidence, and reduced fluvial sediment supply are causing river deltas to drown worldwide, affecting ecosystems and billions of people. Abrupt changes in river course, called avulsions, naturally nourish sinking land with sediment; however, they also create catastrophic flood hazards. Existing observations and models conflict on whether the occurrence of avulsions will change due to relative sea-level rise, hampering the ability to forecast delta response to global climate change. Here, we combined theory, numerical modeling, and field observations to develop a mechanistic framework to predict avulsion frequency on deltas with multiple self-formed lobes that scale with backwater hydrodynamics. Results show that avulsion frequency is controlled by the competition between relative sea-level rise and sediment supply that drives lobe progradation. We find that most large deltas are experiencing sufficiently low progradation rates such that relative sea-level rise enhances aggradation rates\u2014accelerating avulsion frequency and associated hazards compared to preindustrial conditions. Some deltas may face even greater risk; if relative sea-level rise significantly outpaces sediment supply, then avulsion frequency is maximized, delta plains drown, and avulsion locations shift inland, posing new hazards to upstream communities. Results indicate that managed deltas can support more frequent engineered avulsions to recover sinking land; however, there is a threshold beyond which coastal land will be lost, and mitigation efforts should shift upstream.", "date": "2020-07-28", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "117", "number": "30", "publisher": "National Academy of Sciences", "pagerange": "17584-17590", "id_number": "CaltechAUTHORS:20200714-092850643", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200714-092850643", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1912351117", "pmcid": "PMC7395564", "primary_object": { "basename": "17584.full.pdf", "url": "https://authors.library.caltech.edu/records/2k595-pes34/files/17584.full.pdf" }, "related_objects": [ { "basename": "pnas.1912351117.sapp.pdf", "url": "https://authors.library.caltech.edu/records/2k595-pes34/files/pnas.1912351117.sapp.pdf" } ], "pub_year": "2020", "author_list": "Chadwick, Austin J.; Lamb, Michael P.; et al." }, { "id": "https://authors.library.caltech.edu/records/dqqqn-65z85", "eprint_id": 102942, "eprint_status": "archive", "datestamp": "2023-08-19 21:57:24", "lastmod": "2023-10-20 00:39:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Drover-Marcus-W", "name": { "family": "Drover", "given": "Marcus W." }, "orcid": "0000-0002-2186-1040" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Catalytic N\u2082-to-NH\u2083 (or -N\u2082H\u2084) Conversion by Well-Defined Molecular Coordination Complexes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived 9 October 2019. Published online 30 April 2020. \n\nThis article is part of the Reactivity of Nitrogen from the Ground to the Atmosphere special issue. \n\nThe authors are grateful to NIH (GM-070757) for ongoing support of their work exploring (L_n)Fe(N_xH_y) model systems of biological nitrogenases and the Department of Energy (DOE-0235032) for supporting their research towards electrocatalytic N\u2082RR systems. M.W.D. acknowledges NSERC (Banting PDF award to MWD), and M.W.D./M.J.C. thank the Resnick Sustainability Institute at Caltech for fellowships. Dr. Cooper Citek, Dr. Pablo G. Barros, Javier Fajardo Jr., Nina X. Gu, Dr. Heejun Lee, Dr. Alonso Rosas, and Dirk J. Schild are thanked for providing helpful discussion. \n\nAuthor Contributions: M.J.C. and M.W.D. contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1624154.pdf

", "abstract": "Nitrogen fixation, the six-electron/six-proton reduction of N\u2082, to give NH\u2083, is one of the most challenging and important chemical transformations. Notwithstanding the barriers associated with this reaction, significant progress has been made in developing molecular complexes that reduce N\u2082 into its bioavailable form, NH\u2083. This progress is driven by the dual aims of better understanding biological nitrogenases and improving upon industrial nitrogen fixation. In this review, we highlight both mechanistic understanding of nitrogen fixation that has been developed, as well as advances in yields, efficiencies, and rates that make molecular alternatives to nitrogen fixation increasingly appealing. We begin with a historical discussion of N\u2082 functionalization chemistry that traverses a timeline of events leading up to the discovery of the first bona fide molecular catalyst system and follow with a comprehensive overview of d-block compounds that have been targeted as catalysts up to and including 2019. We end with a summary of lessons learned from this significant research effort and last offer a discussion of key remaining challenges in the field.", "date": "2020-06-24", "date_type": "published", "publication": "Chemical Reviews", "volume": "120", "number": "12", "publisher": "American Chemical Society", "pagerange": "5582-5636", "id_number": "CaltechAUTHORS:20200430-151240025", "issn": "0009-2665", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200430-151240025", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM-070757" }, { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemrev.9b00638", "pmcid": "PMC7493999", "primary_object": { "basename": "nihms-1624154.pdf", "url": "https://authors.library.caltech.edu/records/dqqqn-65z85/files/nihms-1624154.pdf" }, "pub_year": "2020", "author_list": "Chalkley, Matthew J.; Drover, Marcus W.; et al." }, { "id": "https://authors.library.caltech.edu/records/zqjds-cq087", "eprint_id": 102695, "eprint_status": "archive", "datestamp": "2023-08-19 21:27:27", "lastmod": "2023-12-22 23:33:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Andrew-Z", "name": { "family": "Zhou", "given": "Andrew Z." } }, { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Enzymatic Lactone-Carbene C\u2012H Insertion to Build Contiguous Chiral Centers", "ispublished": "pub", "full_text_status": "public", "keywords": "cytochrome P450, directed evolution, carbene transfer, C\u2212H functionalization, lactone", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: March 23, 2020; Revised: April 20, 2020; Published: April 21, 2020. \n\nThis work was supported by NSF Division of Molecular and Cellular Biosciences grant MCB-1513007, US Army Research Office Institute for Collaborative Biotechnologies cooperative agreement W911NF-19-2-0026, and US Army Research Office Institute for Collaborative Biotechnologies contract W911NF-19-D-0001. K.C. thanks the Resnick Sustainability Institute at Caltech for fellowship support. \n\nAuthor Contributions: K.C. conceived the project. A.Z.Z. and K.C. performed all the experiments and analysis under the guidance of F.H.A. The manuscript was drafted by K.C. and edited by A.Z.Z. and F.H.A. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cs0c01349_si_001.pdf

", "abstract": "We report a biocatalytic platform of engineered cytochrome P411 enzymes (P450s with axial serine ligation) to carry out efficient lactone-carbene insertion into primary and secondary \u03b1-amino C\u2013H bonds. Directed evolution of a P450 variant, P411-C10, yielded a lineage of enzyme variants capable of forming chiral lactone derivatives with high catalytic efficiency (up to 4000 TTN) and in a stereodivergent manner. For carbene insertion into secondary C\u2013H bonds, a single mutation was discovered to invert the two contiguous chiral centers and lead to the opposite enantiomers of the same major diastereomers. This work demonstrates the utility of engineered enzymes for asymmetric catalysis and highlights the remarkable tunability of these genetically encoded biocatalysts for accessing the desired selectivities.", "date": "2020-05-15", "date_type": "published", "publication": "ACS Catalysis", "volume": "10", "number": "10", "publisher": "American Chemical Society", "pagerange": "5393-5398", "id_number": "CaltechAUTHORS:20200421-095315855", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200421-095315855", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-2-0026" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-D-0001" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1021/acscatal.0c01349", "primary_object": { "basename": "cs0c01349_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zqjds-cq087/files/cs0c01349_si_001.pdf" }, "pub_year": "2020", "author_list": "Zhou, Andrew Z.; Chen, Kai; et al." }, { "id": "https://authors.library.caltech.edu/records/53cbk-4y539", "eprint_id": 102811, "eprint_status": "archive", "datestamp": "2023-08-19 21:26:00", "lastmod": "2023-10-20 00:31:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vyatskikh-A", "name": { "family": "Vyatskikh", "given": "Andrey" }, "orcid": "0000-0002-6917-6931" }, { "id": "Ng-Ryan-C", "name": { "family": "Ng", "given": "Ryan C." }, "orcid": "0000-0002-0527-9130" }, { "id": "Edwards-Bryce", "name": { "family": "Edwards", "given": "Bryce" } }, { "id": "Briggs-R-M", "name": { "family": "Briggs", "given": "Ryan M." } }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Additive Manufacturing of High-Refractive-Index, Nanoarchitected Titanium Dioxide for 3D Dielectric Photonic Crystals", "ispublished": "pub", "full_text_status": "public", "keywords": "additive manufacturing, titanium dioxide, hybrid organic\u2212inorganic material, two-photon lithography, high refractive index, photonic crystals", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 2, 2020; Revised: April 22, 2020; Published: April 27, 2020. \n\nThe authors are grateful for the support of J.R.G.'s DoD Vannevar-Bush Faculty Fellowship. Authors also acknowledge A.V.'s Resnick Sustainability Institute at Caltech Fellowship and NIH Biotechnology Leadership Pre-Doctoral Training Program support. We thank Professor George R. Rossman (Caltech) for his assistance with Raman spectroscopy and FTIR. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl0c00454_si_001.pdf

", "abstract": "Additive manufacturing at small scales enables advances in micro- and nanoelectromechanical systems, micro-optics, and medical devices. Materials that lend themselves to AM at the nanoscale, especially for optical applications, are limited. State-of-the-art AM processes for high-refractive-index materials typically suffer from high porosity and poor repeatability and require complex experimental procedures. We developed an AM process to fabricate complex 3D architectures out of fully dense titanium dioxide (TiO\u2082) with a refractive index of 2.3 and nanosized critical dimensions. Transmission electron microscopy (TEM) analysis proves this material to be rutile phase of nanocrystalline TiO\u2082, with an average grain size of 110 nm and <1% porosity. Proof-of-concept woodpile architectures with 300\u2013600 nm beam dimensions exhibit a full photonic band gap centered at 1.8\u20132.9 \u03bcm, as revealed by Fourier-transform infrared spectroscopy (FTIR) and supported by plane wave expansion simulations. The developed AM process enables advances in 3D MEMS, micro-optics, and prototyping of 3D dielectric PhCs.", "date": "2020-05-13", "date_type": "published", "publication": "Nano Letters", "volume": "20", "number": "5", "publisher": "American Chemical Society", "pagerange": "3513-3520", "id_number": "CaltechAUTHORS:20200427-132503609", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200427-132503609", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Vannever Bush Faculty Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech" }, { "agency": "NIH Predoctoral Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.0c00454", "primary_object": { "basename": "nl0c00454_si_001.pdf", "url": "https://authors.library.caltech.edu/records/53cbk-4y539/files/nl0c00454_si_001.pdf" }, "pub_year": "2020", "author_list": "Vyatskikh, Andrey; Ng, Ryan C.; et al." }, { "id": "https://authors.library.caltech.edu/records/zpfdf-dsp81", "eprint_id": 102447, "eprint_status": "archive", "datestamp": "2023-08-22 04:45:42", "lastmod": "2023-10-20 00:12:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Relating N-H Bond Strengths to the Overpotential for Catalytic Nitrogen Fixation", "ispublished": "pub", "full_text_status": "public", "keywords": "Nitrogen fixation; Reaction mechanisms; Proton transfer; Electron transfer; Thermochemistry", "note": "\u00a9 2020 Wiley\u2010VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nIssue Online: 17 April 2020; Version of Record online: 09 April 2020; Manuscript received: 04 March 2020. \n\nThis research was supported by the National Institutes of Health (GM\u2010070757). M. J. C. thanks the Resnick Sustainability Institute at Caltech for a graduate research fellowship.\n\n

Accepted Version - nihms-1621272.pdf

", "abstract": "The reduction of N\u2082 to NH\u2083 (N\u2082RR) is a globally significant reaction that is challenging due to the inertness of N\u2082. Transition metals can activate N\u2082 and mediate catalytic N\u2082RR, but challenges remain with respect to catalytic efficiency in terms of overpotential and selectivity. We discuss the role of the N\u2013H bond dissociation free energy (BDFE) of metal diazenidos (M\u2010NNH), the first intermediates of N\u2082RR, in determining N2RR efficiency.", "date": "2020-04-30", "date_type": "published", "publication": "European Journal of Inorganic Chemistry", "volume": "2020", "number": "15-16", "publisher": "Wiley", "pagerange": "1353-1357", "id_number": "CaltechAUTHORS:20200409-115738751", "issn": "1434-1948", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200409-115738751", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM070757" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/ejic.202000232", "pmcid": "PMC7566871", "primary_object": { "basename": "nihms-1621272.pdf", "url": "https://authors.library.caltech.edu/records/zpfdf-dsp81/files/nihms-1621272.pdf" }, "pub_year": "2020", "author_list": "Chalkley, Matthew J. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/rszj5-tt860", "eprint_id": 103199, "eprint_status": "archive", "datestamp": "2023-08-19 21:01:21", "lastmod": "2023-10-20 15:46:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Yuan-Zhiquan", "name": { "family": "Yuan", "given": "Zhiquan" } }, { "id": "Wang-Heming", "name": { "family": "Wang", "given": "Heming" }, "orcid": "0000-0003-3861-0624" }, { "id": "Wu-Lue", "name": { "family": "Wu", "given": "Lue" }, "orcid": "0000-0002-7503-7057" }, { "id": "Shen-Boqiang", "name": { "family": "Shen", "given": "Boqiang" }, "orcid": "0000-0003-0697-508X" }, { "id": "Sung-Keeyoon", "name": { "family": "Sung", "given": "Keeyoon" } }, { "id": "Leifer-Stephanie-D", "name": { "family": "Leifer", "given": "Stephanie" }, "orcid": "0000-0002-8980-7825" }, { "id": "Lin-Qiang", "name": { "family": "Lin", "given": "Qiang" } }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry" }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Interleaved difference-frequency generation for microcomb spectral densification in the mid-infrared", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement. \n\nReceived 12 November 2019; revised 3 March 2020; accepted 5 March 2020 (Doc. ID 382992); published 8 April 2020. \n\nThe authors thank Scott Diddams, Christian Frankenberg, Neil Fromer, Qi-Fan Yang, and Xu Yi for helpful discussions. The content of the information does not necessarily reflect the position or the policy of the federal government, and no official endorsement should be inferred. Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. C. B. gratefully acknowledges postdoctoral fellowship support from the Resnick Sustainability Institute at Caltech. \n\nFunding: Defense Threat Reduction Agency (HD-TRA11810047); Air Force Office of Scientific Research (FA9550-18-1-035); Resnick Sustainability Institute for Science, Energy and Sustainability, California Institute of Technology, and the Kavli Nanoscience Institute. \n\nThe authors declare no conflicts of interest.\n\n

Published - optica-7-4-309.pdf

", "abstract": "With their compact size and semiconductor-chip-based operation, frequency microcombs can be an invaluable light source for gas spectrcoscopy. However, the generation of mid-infrared (mid-IR) frequency combs with gigahertz line spacing as required to resolve many gas spectra represents a significant challenge for these devices. Here, a technique referred to as interleaved difference-frequency generation (iDFG) is introduced that densifies the spectral line spacing upon conversion of near-IR comb light into the mid-IR light. A soliton microcomb is used as both a comb light source and microwave oscillator in a demonstration, and the spectrum of methane is measured to illustrate how the resulting mid-IR comb avoids spectral undersampling. Beyond demonstration of the iDFG technique, this work represents an important feasibility step towards more compact and potentially chip-based mid-IR gas spectroscopy modules.", "date": "2020-04-20", "date_type": "published", "publication": "Optica", "volume": "7", "number": "4", "publisher": "Optical Society of America", "pagerange": "309-315", "id_number": "CaltechAUTHORS:20200514-130155611", "issn": "2334-2536", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200514-130155611", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Threat Reduction Agency (DTRA)", "grant_number": "HD-TRA11810047" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0353" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1364/optica.382992", "primary_object": { "basename": "optica-7-4-309.pdf", "url": "https://authors.library.caltech.edu/records/rszj5-tt860/files/optica-7-4-309.pdf" }, "pub_year": "2020", "author_list": "Bao, Chengying; Yuan, Zhiquan; et al." }, { "id": "https://authors.library.caltech.edu/records/vjcb3-v6k56", "eprint_id": 102399, "eprint_status": "archive", "datestamp": "2023-08-22 04:41:25", "lastmod": "2023-10-20 00:10:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Magney-Troy-S", "name": { "family": "Magney", "given": "Troy" }, "orcid": "0000-0002-9033-0024" }, { "id": "Dutta-Debsunder", "name": { "family": "Dutta", "given": "Debsunder" } }, { "id": "Yin-Yi", "name": { "family": "Yin", "given": "Yi" }, "orcid": "0000-0003-4750-4997" }, { "id": "K\u00f6hler-Philipp", "name": { "family": "K\u00f6hler", "given": "Philipp" }, "orcid": "0000-0002-7820-1318" }, { "id": "Grossmann-Katja", "name": { "family": "Grossmann", "given": "Katja" }, "orcid": "0000-0002-5154-197X" }, { "id": "Stutz-Jochen", "name": { "family": "Stutz", "given": "Jochen" }, "orcid": "0000-0001-6368-7629" }, { "id": "Dold-Christian", "name": { "family": "Dold", "given": "Christian" } }, { "id": "Hatfield-Jerry", "name": { "family": "Hatfield", "given": "Jerry" } }, { "id": "Guan-Kaiyu", "name": { "family": "Guan", "given": "Kaiyu" } }, { "id": "Peng-Bin", "name": { "family": "Peng", "given": "Bin" }, "orcid": "0000-0002-7284-3010" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "From the Ground to Space: Using Solar-Induced Chlorophyll Fluorescence to Estimate Crop Productivity", "ispublished": "pub", "full_text_status": "public", "keywords": "crop monitoring; fluorescence; gross primary production; net primary production", "note": "\u00a9 2020 American Geophysical Union. \n\nReceived 10 FEB 2020; Accepted 4 MAR 2020; Accepted article online 9 MAR 2020. \n\nPart of this research was funded by the NASA Carbon Cycle Science program (grant NNX17AE14G). L.H. thanks the Resnick Sustainability Institute at Caltech for fellowship support. TROPOMI SIF data generation by P.K. and C.F. is funded by the Earth Science U.S. Participating Investigator program (grant NNX15AH95G). TROPOMI SIF product is available at ftp://fluo.gps.caltech.edu/data/tropomi/. County\u2010level crop statistics is available at the USDA NASS Quick Stats Database (quickstats.nass.usda.gov). Crop\u2010specific land cover data layer CDL can be accessed at https://nassgeodata.gmu.edu/CropScape/.\n\n

Published - 2020GL087474.pdf

Supplemental Material - grl60362-sup-0001-2020gl087474-si.docx

", "abstract": "Timely and accurate monitoring of crops is essential for food security. Here, we examine how well solar\u2010induced chlorophyll fluorescence (SIF) can inform crop productivity across the United States. Based on tower\u2010level observations and process\u2010based modeling, we find highly linear gross primary production (GPP):SIF relationships for C4 crops, while C3 crops show some saturation of GPP at high light when SIF continues to increase. C4 crops yield higher GPP:SIF ratios (30\u201350%) primarily because SIF is most sensitive to the light reactions (does not account for photorespiration). Scaling to the satellite, we compare SIF from the TROPOspheric Monitoring Instrument (TROPOMI) against tower\u2010derived GPP and county\u2010level crop statistics. Temporally, TROPOMI SIF strongly agrees with GPP observations upscaled across a corn and soybean dominated cropland (R\u00b2 = 0.89). Spatially, county\u2010level TROPOMI SIF correlates with crop productivity (R\u00b2 = 0.72; 0.86 when accounting for planted area and C3/C4 contributions), highlighting the potential of SIF for reliable crop monitoring.", "date": "2020-04-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "47", "number": "7", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020GL087474", "id_number": "CaltechAUTHORS:20200408-093014100", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200408-093014100", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX17AE14G" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA", "grant_number": "NNX15AH95G" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020gl087474", "primary_object": { "basename": "2020GL087474.pdf", "url": "https://authors.library.caltech.edu/records/vjcb3-v6k56/files/2020GL087474.pdf" }, "related_objects": [ { "basename": "grl60362-sup-0001-2020gl087474-si.docx", "url": "https://authors.library.caltech.edu/records/vjcb3-v6k56/files/grl60362-sup-0001-2020gl087474-si.docx" } ], "pub_year": "2020", "author_list": "He, Liyin; Magney, Troy; et al." }, { "id": "https://authors.library.caltech.edu/records/5m95r-7g656", "eprint_id": 102170, "eprint_status": "archive", "datestamp": "2023-08-19 20:58:34", "lastmod": "2023-12-22 23:33:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Engineering cytochrome P450s for enantioselective cyclopropenation of internal alkynes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 3, 2020; Published: March 29, 2020. \n\nThis work was supported by NSF Division of Molecular and Cellular Biosciences grant MCB-1513007, US Army Research Office Institute for Collaborative Biotechnologies cooperative agreement W911NF-19-2-0026, and US Army Research Office Institute for Collaborative Biotechnologies contract W911NF-19-D-0001. K.C. thanks the Resnick Sustainability Institute at Caltech for fellowship support. We thank R. K. Zhang, N. P. Dunham, D. J. Wackelin, Y. Yang, and M. Garcia-Borr\u00e0s for helpful discussions and comments. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja0c01313_si_001.pdf

", "abstract": "We report a biocatalytic platform of engineered cytochrome P450 enzymes to carry out efficient cyclopropene synthesis via carbene transfer to internal alkynes. Directed evolution of a serine-ligated P450 variant, P411-C10, yielded a lineage of engineered P411 enzymes that together accommodate a variety of internal aromatic alkynes as substrates for cyclopropenation with unprecedented efficiencies and stereoselectivities (up to 5760 TTN, and all with >99.9% ee). Using an internal aliphatic alkyne bearing a propargylic ether group, different P411 variants can selectively catalyze cyclopropene formation, carbene insertion into a propargylic C\u2013H bond or [3 + 2]-cycloaddition. This tunable reaction selectivity further highlights the benefit of using genetically encoded catalysts to address chemoselectivity challenges.", "date": "2020-04-15", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "142", "number": "15", "publisher": "American Chemical Society", "pagerange": "6891-6895", "id_number": "CaltechAUTHORS:20200330-105819372", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200330-105819372", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-2-0026" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-D-0001" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1021/jacs.0c01313", "primary_object": { "basename": "ja0c01313_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5m95r-7g656/files/ja0c01313_si_001.pdf" }, "pub_year": "2020", "author_list": "Chen, Kai and Arnold, Frances H." }, { "id": "https://authors.library.caltech.edu/records/5htxd-c1q08", "eprint_id": 101732, "eprint_status": "archive", "datestamp": "2023-08-19 20:54:18", "lastmod": "2025-04-23 15:19:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Li-Xueqian", "name": { "family": "Li", "given": "Xueqian" }, "orcid": "0000-0002-1197-3743" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Optical Excitation of a Nanoparticle Cu/p-NiO Photocathode Improves Reaction Selectivity for CO\u2082 Reduction in Aqueous Electrolytes", "ispublished": "pub", "full_text_status": "public", "keywords": "artificial photosynthesis, photoelectrochemistry, hot holes, plasmonic\nphotocathode, CO2 reduction", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: November 25, 2019; Revised: March 3, 2020; Published: March 5, 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. G.T. acknowledges support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship, grant no. P2EZP2_159101, and the Advanced Mobility Fellowship, grant no. P300P2_171417. A.J.W. acknowledges support from the Resnick Sustainability Institute at the California Institute of Technology and the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 1745301. We thank Professor Brian McCloskey for sharing the design of the photoelectrochemical cell for temperature-controlled CO\u2082 reduction experiments. We also thank Dr. Matthias Richter for XPS characterization of p-type NiO and Cu/p-NiO films, which was performed at the Molecular Materials Research Center in the Beckman Institute of the California Institute of Technology. \n\nAuthor Contributions: J.S.D. and H.A.A. conceived the idea, designed the experiments, and wrote the manuscript. J.S.D. performed all photoelectrochemical experiments with assistance from A.J.W. and X.L. J.S.D., G.T., A.J.W., and X.L. fabricated and characterized devices. W.-H.C. performed optical characterization of materials and assisted with calibration and maintenance of gas chromatography equipment. H.A.A. supervised the project. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl9b04895_si_001.pdf

", "abstract": "We report the light-induced modification of catalytic selectivity for photoelectrochemical CO\u2082 reduction in aqueous media using copper (Cu) nanoparticles dispersed onto p-type nickel oxide (p-NiO) photocathodes. Optical excitation of Cu nanoparticles generates hot electrons available for driving CO\u2082 reduction on the Cu surface, while charge separation is accomplished by hot-hole injection from the Cu nanoparticles into the underlying p-NiO support. Photoelectrochemical studies demonstrate that optical excitation of plasmonic Cu/p-NiO photocathodes imparts increased selectivity for CO\u2082 reduction over hydrogen evolution in aqueous electrolytes. Specifically, we observed that plasmon-driven CO\u2082 reduction increased the production of carbon monoxide and formate, while simultaneously reducing the evolution of hydrogen. Our results demonstrate an optical route toward steering the selectivity of artificial photosynthetic systems with plasmon-driven photocathodes for photoelectrochemical CO\u2082 reduction in aqueous media.", "date": "2020-04-08", "date_type": "published", "publication": "Nano Letters", "volume": "20", "number": "4", "publisher": "American Chemical Society", "pagerange": "2348-2358", "id_number": "CaltechAUTHORS:20200305-145718553", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200305-145718553", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300P2_171417" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.9b04895", "primary_object": { "basename": "nl9b04895_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5htxd-c1q08/files/nl9b04895_si_001.pdf" }, "pub_year": "2020", "author_list": "DuChene, Joseph S.; Tagliabue, Giulia; et al." }, { "id": "https://authors.library.caltech.edu/records/cx20r-0g111", "eprint_id": 102168, "eprint_status": "archive", "datestamp": "2023-08-19 20:55:21", "lastmod": "2023-10-19 23:54:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hansen-C-J", "name": { "family": "Hansen", "given": "Charles J." }, "orcid": "0000-0003-4981-9087" }, { "id": "Zak-J-J", "name": { "family": "Zak", "given": "Joshua J." }, "orcid": "0000-0003-3793-7254" }, { "id": "Martinolich-A-J", "name": { "family": "Martinolich", "given": "Andrew J." }, "orcid": "0000-0002-7866-9594" }, { "id": "Ko-Jesse-S", "name": { "family": "Ko", "given": "Jesse S." }, "orcid": "0000-0001-6965-4174" }, { "id": "Bashian-N-H", "name": { "family": "Bashian", "given": "Nicholas H." }, "orcid": "0000-0001-9984-2539" }, { "id": "Kaboudvand-F", "name": { "family": "Kaboudvand", "given": "Farnaz" }, "orcid": "0000-0002-8366-0041" }, { "id": "Van-der-Ven-A", "name": { "family": "Van der Ven", "given": "Anton" } }, { "id": "Melot-B-C", "name": { "family": "Melot", "given": "Brent C." }, "orcid": "0000-0002-7078-8206" }, { "id": "Weker-J-N", "name": { "family": "Weker", "given": "Johanna Nelson" }, "orcid": "0000-0001-6856-3203" }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Multielectron, Cation and Anion Redox in Lithium-Rich Iron Sulfide Cathodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: January 23, 2020; Published: March 30, 2020. \n\nThis work was supported as part of the Center for Synthetic Control Across Length-scales for Advancing Rechargeables (SCALAR), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award No. DE-SC0019381. C.J.H. was supported by a Beckman-Gray Graduate Student Fellowship made possible by the Arnold and Mabel Beckman Foundation. J.J.Z. acknowledges support from the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1745301. A.J.M. acknowledges a postdoctoral fellowship from the Resnick Sustainability Institute at Caltech. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515. The authors thank Prof. Ryan G. Hadt and Sarah C. Bevilacqua for useful discussions.\n\n

Supplemental Material - ja0c00909_si_001.pdf

", "abstract": "Conventional Li-ion cathodes store charge by reversible intercalation of Li coupled to metal cation redox. There has been increasing interest in new materials capable of accommodating more than one Li per transition-metal center, thereby yielding higher charge storage capacities. We demonstrate here that the lithium-rich layered iron sulfide Li\u2082FeS\u2082 as well as a new structural analogue, LiNaFeS\u2082, reversibly store \u22651.5 electrons per formula unit and support extended cycling. Ex situ and operando structural and spectroscopic data indicate that delithiation results in reversible oxidation of Fe\u00b2\u207a concurrent with an increase in the covalency of the Fe\u2013S interactions, followed by reversible anion redox: 2 S\u00b2\u207b/(S\u2082)\u00b2\u207b. S K-edge spectroscopy unequivocally proves the contribution of the anions to the redox processes. The structural response to the oxidation processes is found to be different in Li\u2082FeS\u2082 in contrast to that in LiNaFeS\u2082, which we suggest is the cause for capacity fade in the early cycles of LiNaFeS\u2082. The materials presented here have the added benefit of avoiding resource-sensitive transition metals such as Co and Ni. In contrast to Li-rich oxide materials that have been the subject of so much recent study and that suffer capacity fade and electrolyte degradation issues, the materials presented here operate within the stable potential window of the electrolyte, permitting a clearer understanding of the underlying processes.", "date": "2020-04-08", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "142", "number": "14", "publisher": "American Chemical Society", "pagerange": "6737-6749", "id_number": "CaltechAUTHORS:20200330-101312532", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200330-101312532", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019381" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.0c00909", "primary_object": { "basename": "ja0c00909_si_001.pdf", "url": "https://authors.library.caltech.edu/records/cx20r-0g111/files/ja0c00909_si_001.pdf" }, "pub_year": "2020", "author_list": "Hansen, Charles J.; Zak, Joshua J.; et al." }, { "id": "https://authors.library.caltech.edu/records/ynj8h-ca285", "eprint_id": 101691, "eprint_status": "archive", "datestamp": "2023-08-19 20:33:35", "lastmod": "2025-04-23 19:31:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Dunn-Emily", "name": { "family": "Dunn", "given": "Emily" } }, { "id": "DuChene-J-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Bicarbonate or Carbonate Processes for Coupling Carbon Dioxide Capture and Electrochemical Conversion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 2, 2020; Accepted: February 26, 2020. Publication Date: March 3, 2020. \n\nThis work is done within the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number De-SC0004993. A.J.W. acknowledges support from the Resnick Sustainability Institute at Caltech for fellowship support and from the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 174530. \n\nAuthor Contributions: A.J.W, J.S.D, and H.A.A. conceived the idea and examined the feasibility of such a process. A.J.W. and E.D. performed all of the calculations and research required to complete the energy analysis of various systems. J.S.D. advised throughout the process and provided valuable input for determining the viability of various proposed processes. A.J.W., J.S.D, and H.A.A. wrote the Viewpoint, and all authors commented on the manuscript. \n\nAny opinions, findings, and conclusions expressed in this material are those of the authors and do not necessary reflect those of DOE or NSF. Views expressed in this Viewpoint are those of the authors and not necessarily the views of the ACS. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nz0c00234_si_001.pdf

", "abstract": "Designing a scalable system to capture CO\u2082 from the air and convert it into valuable chemicals, fuels, and materials could be transformational for mitigating climate change. Climate models predict that negative greenhouse gas emissions will be required by the year 2050 in order to stay below a 2 \u00b0C change in global temperature. The processes of CO\u2082 capture, CO\u2082 conversion, and finally product separation all require significant energy inputs; devising a system that simultaneously minimizes the energy required for all steps is an important challenge. To date, a variety of prototype or pilot-level CO\u2082 capture and/or conversion systems have been designed and built targeting the individual objectives of either capture or conversion. One approach has focused on CO\u2082 removal from the atmosphere and storage of pure pressurized CO\u2082. Other efforts have concentrated on CO\u2082 conversion processes, such as electrochemical reduction or fermentation. Only a few concepts or analyses have been developed for complete end-to-end processes that perform both CO\u2082 capture and transformation.", "date": "2020-03-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "3", "publisher": "American Chemical Society", "pagerange": "940-945", "id_number": "CaltechAUTHORS:20200304-074750016", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200304-074750016", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-174530" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.0c00234", "primary_object": { "basename": "nz0c00234_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ynj8h-ca285/files/nz0c00234_si_001.pdf" }, "pub_year": "2020", "author_list": "Welch, Alex J.; Dunn, Emily; et al." }, { "id": "https://authors.library.caltech.edu/records/gy205-z0r22", "eprint_id": 99432, "eprint_status": "archive", "datestamp": "2023-08-19 20:08:27", "lastmod": "2023-10-18 18:18:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Subhas-A-V", "name": { "family": "Subhas", "given": "Adam V." }, "orcid": "0000-0002-7688-6624" }, { "id": "Adkins-J-F", "name": { "family": "Adkins", "given": "Jess F." }, "orcid": "0000-0002-3174-5190" }, { "id": "Dong-Sijia-S", "name": { "family": "Dong", "given": "Sijia" }, "orcid": "0000-0002-5811-9333" }, { "id": "Rollins-N-E", "name": { "family": "Rollins", "given": "Nick E." } }, { "id": "Berelson-W-M", "name": { "family": "Berelson", "given": "William M." } } ] }, "title": "The carbonic anhydrase activity of sinking and suspended particles in the North Pacific Ocean", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 Association for the Sciences of Limnology and Oceanography. \n\nIssue Online: 05 March 2020; Version of Record online: 11 October 2019; Manuscript accepted: 22 August 2019; Manuscript revised:\n02 May 2019; Manuscript received: 12 December 2018. \n\nWe thank the entire science party and the R/V Kilo Moana crew on the CDisK\u2010IV cruise. In particular, we thank Doug Hammond and Alex Sessions for providing the in situ pumps, Nathan Kemnitz, Yi Hou, and Abby Lunstrum for help in working up pump filter and multicore samples, and Will Gray for helping to pick pteropod samples. We greatly thank Brian Hopkinson and two anonymous reviewers for their helpful and insightful comments and suggestions throughout the review process. This manuscript was significantly improved thanks to their efforts. We also acknowledge funding sources from NSF (OCE1220600 and OCE1220302), and the Resnick Sustainability Institute Graduate Fellowship for A.V.S. \n\nConflict of Interest: None declared.", "abstract": "The enzyme carbonic anhydrase (CA) is crucial to many physiological processes involving CO\u2082, from photosynthesis and respiration, to calcification and CaCO\u2083 dissolution. We present new measurements of CA activity along a North Pacific transect, on samples from in situ pumps, sediment traps, discreet plankton samples from the ship's underway seawater line, plankton tows, and surface sediment samples from multicores. CA activity is highest in the surface ocean and decreases with depth, both in suspended and sinking particles. Subpolar gyre surface particles exhibit 10\u00d7 higher CA activity per liter of seawater compared to subtropical gyre surface particles. Activity persists to 4700\u2009m in the subpolar gyre, but only to 1000\u2009m in the subtropics. All sinking CA activity normalized to particulate organic carbon (POC) follows a single relationship (CA/POC = 1.9\u2009\u00b1\u20090.2\u2009\u00d7\u200910\u207b\u2077 mol\u2009mol\u207b\u00b9). This relationship is consistent with CA/POC values in subpolar plankton tow material, suspended particles, and core top sediments. We hypothesize that most subpolar CA activity is associated with rapidly sinking diatom blooms, consistent with a large mat of diatomaceous material identified on the seafloor. Compared to the basin\u2010wide sinking CA/POC relationship, a lower subtropical CA/POC suggests that the inventory of subtropical biomass is different in composition from exported material. Pteropods also demonstrate substantial CA activity. Scaled to the volume within pteropod shells, first\u2010order CO\u2082 hydration rate constants are elevated \u2265\u20091000\u00d7 above background. This kinetic enhancement is large enough to catalyze carbonate dissolution within microenvironments, providing observational evidence for CA\u2010catalyzed, respiration\u2010driven CaCO\u2083 dissolution in the shallow North Pacific.", "date": "2020-03", "date_type": "published", "publication": "Limnology and Oceanography", "volume": "65", "number": "3", "publisher": "American Society of Limnology and Oceanography", "pagerange": "637-651", "id_number": "CaltechAUTHORS:20191024-091357425", "issn": "0024-3590", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191024-091357425", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OCE-1220600" }, { "agency": "NSF", "grant_number": "OCE-1220302" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/lno.11332", "pub_year": "2020", "author_list": "Subhas, Adam V.; Adkins, Jess F.; et al." }, { "id": "https://authors.library.caltech.edu/records/cc67x-y4s22", "eprint_id": 100816, "eprint_status": "archive", "datestamp": "2023-08-22 04:10:19", "lastmod": "2023-12-22 23:33:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Engineering new catalytic activities in enzymes", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Biocatalysis; Biosynthesis; Catalysis; Enzymes", "note": "\u00a9 2020 Springer Nature Limited.\n\nReceived 25 August 2019; Accepted 21 October 2019; Published 20 January 2020. \n\nWe thank D. J. Wackelin and Y. Yang (Caltech) for helpful discussions and comments on the manuscript. This work was supported by NSF Division of Molecular and Cellular Biosciences grant no. MCB-1513007, the US Army Research Office Institute for Collaborative Biotechnologies (cooperative agreement no. W911NF-19-2-0026) and the US Army Research Office Institute for Collaborative Biotechnologies (contract no. W911NF-19-D-0001). K.C. thanks the Resnick Sustainability Institute at Caltech for fellowship support. The content of this paper does not necessarily reflect the position or the policy of the funding agencies, and no official endorsement should be inferred. \n\nAuthor Contributions: All authors participated in designing and writing the manuscript. \n\nThe authors declare no competing interests.", "abstract": "The efficiency, selectivity and sustainability benefits offered by enzymes are enticing chemists to consider biocatalytic transformations to complement or even supplant more traditional synthetic routes. Increasing demands for efficient and versatile synthetic methods, combined with powerful new discovery and engineering tools, has prompted innovations in biocatalysis, especially the development of new enzymes for precise transformations or 'molecular editing'. As a result, the past decade has witnessed an impressive expansion of the catalytic repertoire of enzymes to include new and useful transformations not known (or relevant) in the biological world. In this Review we illustrate various ways in which researchers have approached using the catalytic machineries of enzymes for new-to-nature transformations. These efforts have identified genetically encoded catalysts that can be tuned and diversified by engineering the protein sequence, particularly by directed evolution. Discovery and improvement of these new enzyme activities is opening a floodgate that connects the chemistry of the biological world to that invented by humans over the past 100 years.", "date": "2020-03", "date_type": "published", "publication": "Nature Catalysis", "volume": "3", "number": "3", "publisher": "Springer", "pagerange": "203-213", "id_number": "CaltechAUTHORS:20200121-114421759", "issn": "2520-1158", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200121-114421759", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-2-0026" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-19-D-0001" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1038/s41929-019-0385-5", "pub_year": "2020", "author_list": "Chen, Kai and Arnold, Frances H." }, { "id": "https://authors.library.caltech.edu/records/wf6s3-za481", "eprint_id": 99475, "eprint_status": "archive", "datestamp": "2023-08-19 20:00:57", "lastmod": "2023-10-18 18:20:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jhalani-Vatsal-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Chen-Hsiao-Yi", "name": { "family": "Chen", "given": "Hsiao-Yi" }, "orcid": "0000-0003-1962-5767" }, { "id": "Palummo-Maurizia", "name": { "family": "Palummo", "given": "Maurizia" }, "orcid": "0000-0002-3097-8523" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Precise radiative lifetimes in bulk crystals from first principles: the case of wurtzite gallium nitride", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 IOP Publishing Ltd. \n\nReceived 5 September 2019; Revised 22 October 2019; Accepted 7 November 2019; Accepted Manuscript online 7 November 2019.\n\nThe authors thank Davide Sangalli for fruitful discussions. V.A.J. thanks the Resnick Sustainability Institute at Caltech for fellowship support. This work was partially supported by the Department of Energy under Grant No. de-sc0019166, which provided for theory and method development, and by the National Science Foundation under Grant No. ACI-1642443, which provided for code development. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. M.P. thanks CINECA for computational resources.\n\n

Submitted - 1908.09962.pdf

", "abstract": "Gallium nitride (GaN) is a key semiconductor for solid-state lighting, but its radiative processes are not fully understood. Here we show a first-principles approach to accurately compute the radiative lifetimes in bulk uniaxial crystals, focusing on wurtzite GaN. Our computed radiative lifetimes are in very good agreement with experiment up to 100 K. We show that taking into account excitons (through the Bethe-Salpeter equation) and spin-orbit coupling to include the exciton fine structure is essential for computing accurate radiative lifetimes. A model for exciton dissociation into free carriers allows us to compute the radiative lifetimes up to room temperature. Our work enables precise radiative lifetime calculations in III-nitrides and other anisotropic solid-state emitters.", "date": "2020-02-20", "date_type": "published", "publication": "Journal of Physics: Condensed Matter", "volume": "32", "number": "8", "publisher": "IOP", "pagerange": "Art. No. 084001", "id_number": "CaltechAUTHORS:20191025-161427443", "issn": "0953-8984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191025-161427443", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019166" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1088/1361-648x/ab5563", "primary_object": { "basename": "1908.09962.pdf", "url": "https://authors.library.caltech.edu/records/wf6s3-za481/files/1908.09962.pdf" }, "pub_year": "2020", "author_list": "Jhalani, Vatsal A.; Chen, Hsiao-Yi; et al." }, { "id": "https://authors.library.caltech.edu/records/jq765-aw131", "eprint_id": 100275, "eprint_status": "archive", "datestamp": "2023-08-22 03:58:47", "lastmod": "2023-10-18 19:48:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Seong-Shik", "name": { "family": "Kim", "given": "Seong Shik" }, "orcid": "0000-0003-2604-6392" }, { "id": "Bevilacqua-S-C", "name": { "family": "Bevilacqua", "given": "Sarah C." }, "orcid": "0000-0002-6834-7145" }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Conditioning-Free Mg Electrolyte by the Minor Addition of Mg(HMDS)\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "magnesium electrolyte; magnesium electrodeposition; electrolyte speciation; conditioning-free electrolyte", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: September 15, 2019; Accepted: November 27, 2019; Published: December 11, 2019. \n\nSpecial Issue: Young Investigator Forum. \n\nS.C.B. acknowledges a graduate fellowship from the Resnick Sustainability Institute at Caltech. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - am9b16710_si_001.pdf

", "abstract": "Mg-based batteries are an attractive next-generation energy storage chemistry due to the high natural abundance and inexpensive cost of Mg, along with the high theoretical energy density compared to that of conventional Li-ion chemistry. The greater energy density is predicated on a Mg metal anode, and pathways to achieving reversible Mg electrodeposition and stripping are reliant on the development of Mg electrolytes. Although Mg electrolyte chemistry has advanced significantly from the reactive Grignards of the 1920s to the carboranes of this decade, there remains significant challenges in correlating the Mg metal anode electrochemistry with the composition of the electrolyte salts as a result of the complicated interface of Mg metal and the electrolyte. To probe the effect of the interface on Mg electrodeposition, we turn to an electrolyte with a known solution-phase composition: the magnesium aluminum chloride complex (MACC) electrolyte. The MACC electrolyte requires electrolytic conditioning to support reversible Mg electrodeposition and stripping. Here, we show that a small concentration (2\u20135 mM) of Mg(HMDS)\u2082 with respect to the MACC electrolyte salts suppresses Al\u00b3\u207a deposition and promotes reversible Mg electrodeposition and stripping in the first cycle. The significant effect of a small concentration of additive is attributed to changes to the electrode interface. The impact of the Mg interface on the observed electrochemical performance is discussed.", "date": "2020-02-05", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "12", "number": "5", "publisher": "American Chemical Society", "pagerange": "5226-5233", "id_number": "CaltechAUTHORS:20191212-105210844", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191212-105210844", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsami.9b16710", "primary_object": { "basename": "am9b16710_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jq765-aw131/files/am9b16710_si_001.pdf" }, "pub_year": "2020", "author_list": "Kim, Seong Shik; Bevilacqua, Sarah C.; et al." }, { "id": "https://authors.library.caltech.edu/records/92n3d-9tc85", "eprint_id": 101007, "eprint_status": "archive", "datestamp": "2023-08-19 19:41:55", "lastmod": "2023-10-20 22:16:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huo-Haohua", "name": { "family": "Huo", "given": "Haohua" } }, { "id": "Gorsline-Bradley-J", "name": { "family": "Gorsline", "given": "Bradley J." } }, { "id": "Fu-G-C", "name": { "family": "Fu", "given": "Gregory C." }, "orcid": "0000-0002-0927-680X" } ] }, "title": "Catalyst-controlled doubly enantioconvergent coupling of racemic alkyl nucleophiles and electrophiles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Association for the Advancement of Science.\nThis is an article distributed under the terms of the Science Journals Default License. \n\nReceived 4 September 2019; accepted 26 November 2019. \n\nWe thank S. H. Jungbauer, S. C. Virgil, L. M. Henling, D. G. Vander Velde, H. Yin, D. J. Freas, W. Zhang, and Z. Yang for assistance and discussions. \n\nFunding: Support has been provided by the National Institutes of Health (National Institute of General Medical Sciences, R37-GM62871). H.H. thanks the Resnick Sustainability Institute at Caltech for fellowship support. \n \nAuthor contributions: H.H. and B.J.G. performed all experiments. H.H. and G.C.F. wrote the manuscript. All authors contributed to the analysis and the interpretation of the results. \n\nThe authors declare no competing interests. \n\nData and materials availability: The data that support the findings of this study are available in the paper, in its supplementary materials (experimental procedures and characterization data), and from the Cambridge Crystallographic Data Centre (CCDC) (www.ccdc.cam.ac.uk/structures; crystallographic data are available free of charge under CCDC reference numbers 1935944 and 1935945).\n\n

Accepted Version - nihms-1566755.pdf

Supplemental Material - aaz3855_Huo_SM.pdf

", "abstract": "Stereochemical control in the construction of carbon-carbon bonds between an alkyl electrophile and an alkyl nucleophile is a persistent challenge in organic synthesis. Classical substitution reactions via S_N1 and S_N2 pathways are limited in their ability to generate carbon-carbon bonds (inadequate scope, due to side reactions such as rearrangements and eliminations) and to control stereochemistry when beginning with readily available racemic starting materials (racemic products). Here, we report a chiral nickel catalyst that couples racemic electrophiles (propargylic halides) with racemic nucleophiles (\u03b2-zincated amides) to form carbon-carbon bonds in doubly stereoconvergent processes, affording a single stereoisomer of the product from two stereochemical mixtures of reactants.", "date": "2020-01-31", "date_type": "published", "publication": "Science", "volume": "367", "number": "6477", "publisher": "American Association for the Advancement of Science", "pagerange": "559-564", "id_number": "CaltechAUTHORS:20200130-135407173", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200130-135407173", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R37-GM62871" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/science.aaz3855", "pmcid": "PMC7566878", "primary_object": { "basename": "nihms-1566755.pdf", "url": "https://authors.library.caltech.edu/records/92n3d-9tc85/files/nihms-1566755.pdf" }, "related_objects": [ { "basename": "aaz3855_Huo_SM.pdf", "url": "https://authors.library.caltech.edu/records/92n3d-9tc85/files/aaz3855_Huo_SM.pdf" } ], "pub_year": "2020", "author_list": "Huo, Haohua; Gorsline, Bradley J.; et al." }, { "id": "https://authors.library.caltech.edu/records/2fyvq-tc556", "eprint_id": 100727, "eprint_status": "archive", "datestamp": "2023-08-22 03:35:11", "lastmod": "2023-10-18 21:48:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Shaoqing", "name": { "family": "Chen", "given": "Shaoqing" }, "orcid": "0000-0002-6700-292X" }, { "id": "Chen-Bin", "name": { "family": "Chen", "given": "Bin" } }, { "id": "Feng-Kuishuang", "name": { "family": "Feng", "given": "Kuishuang" }, "orcid": "0000-0001-5139-444X" }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Fromer-N-A", "name": { "family": "Fromer", "given": "Neil" } }, { "id": "Tan-Xianchun", "name": { "family": "Tan", "given": "Xianchun" } }, { "id": "Alsaedi-A", "name": { "family": "Alsaedi", "given": "Ahmed" } }, { "id": "Hayat-T", "name": { "family": "Hayat", "given": "Tasawar" } }, { "id": "Weisz-H", "name": { "family": "Weisz", "given": "Helga" }, "orcid": "0000-0001-8208-5199" }, { "id": "Schellnhuber-H-J", "name": { "family": "Schellnhuber", "given": "Hans Joachim" } }, { "id": "Hubacek-K", "name": { "family": "Hubacek", "given": "Klaus" }, "orcid": "0000-0003-2561-6090" } ] }, "title": "Physical and virtual carbon metabolism of global cities", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate-change policy; Energy and society", "note": "\u00a9 2020 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 06 November 2018; Accepted 30 October 2019; Published 10 January 2020. \n\nThis work was supported by the National Science Fund for Distinguished Young Scholars of China (71725005), Natural Science Funds for Distinguished Young Scholar of Guangdong Province, China (2018B030306032), Beijing Outstanding Young Scientist Program (BJJWZYJH01201910027031), the National Natural Science Foundation of China (71704015, 71874097, and 71961137009), Strategic Priority Research Program of Chinese Academy of Sciences (No. XDA20100104), and the National Key Research & Development Program (2016YFA0602304). Z.L. and N.F. acknowledge support from the Resnick Sustainability Institute at California Institute of Technology. Z.L. acknowledges Beijing Natural Science Foundation (JQ19032) and the Qiu Shi Science & Technologies Foundation. K.H was partly supported by the Czech Science Foundation under the project VEENEX (GA \u010cR no. 16-17978S). The authors would like to thank Prof. Laixiang Sun, Prof. John Crittenden and Prof. Karen Seto for their constructive comments on the idea of this study. S. Chen wants to give special thanks to the selfless support from his loving family, especially his better half X. Li during the writing of this paper. \n\nData availability: The sources of energy and material flow data for the 16 global cities are provided in Supplementary Table 3. Other supporting urban socioeconomic and metabolic data have been linked to the literature or websites cited in the paper. \n\nCode availability: Programming code for carbon flow model is available from the corresponding author on request. \n\nAuthor Contributions: S.C., B.C., and K.H. designed the research; S.C., K.F., and Z.L. compiled the carbon data; S.C., K.H., and Z.L. developed the model and performed global analyses; S.C., B.C., K.F., Z.L., N.F., X.T., A. A., T.H., H.W., H.J.S., and K.H. contributed to results interpretation and paper writing. \n\nThe authors declare no competing interests.\n\n

Published - s41467-019-13757-3.pdf

Supplemental Material - 41467_2019_13757_MOESM1_ESM.pdf

", "abstract": "Urban activities have profound and lasting effects on the global carbon balance. Here we develop a consistent metabolic approach that combines two complementary carbon accounts, the physical carbon balance and the fossil fuel-derived gaseous carbon footprint, to track carbon coming into, being added to urban stocks, and eventually leaving the city. We find that over 88% of the physical carbon in 16 global cities is imported from outside their urban boundaries, and this outsourcing of carbon is notably amplified by virtual emissions from upstream activities that contribute 33\u201368% to their total carbon inflows. While 13\u201333% of the carbon appropriated by cities is immediately combusted and released as CO\u2082, between 8 and 24% is stored in durable household goods or becomes part of other urban stocks. Inventorying carbon consumed and stored for urban metabolism should be given more credit for the role it can play in stabilizing future global climate.", "date": "2020-01-10", "date_type": "published", "publication": "Nature Communications", "volume": "11", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 182", "id_number": "CaltechAUTHORS:20200115-080354713", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200115-080354713", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Fund for Distinguished Young Scholars of China", "grant_number": "71725005" }, { "agency": "Natural Science Funds for Distinguished Young Scholar of Guangdong Province", "grant_number": "2018B030306032" }, { "agency": "Beijing Outstanding Young Scientist Program", "grant_number": "BJJWZYJH01201910027031" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71704015" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71874097" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71961137009" }, { "agency": "Chinese Academy of Sciences", "grant_number": "XDA20100104" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2016YFA0602304" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Beijing Natural Science Foundation", "grant_number": "JQ19032" }, { "agency": "Qiu Shi Science & Technologies Foundation" }, { "agency": "Czech Science Foundation", "grant_number": "16-17978S" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-019-13757-3", "pmcid": "PMC6954253", "primary_object": { "basename": "s41467-019-13757-3.pdf", "url": "https://authors.library.caltech.edu/records/2fyvq-tc556/files/s41467-019-13757-3.pdf" }, "related_objects": [ { "basename": "41467_2019_13757_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/2fyvq-tc556/files/41467_2019_13757_MOESM1_ESM.pdf" } ], "pub_year": "2020", "author_list": "Chen, Shaoqing; Chen, Bin; et al." }, { "id": "https://authors.library.caltech.edu/records/nfcn9-2a530", "eprint_id": 95420, "eprint_status": "archive", "datestamp": "2023-08-19 19:12:48", "lastmod": "2025-04-23 15:20:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Went-C-M", "name": { "family": "Went", "given": "Cora M." } }, { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Jahelka-P-R", "name": { "family": "Jahelka", "given": "Phillip R." }, "orcid": "0000-0002-1460-7933" }, { "id": "Kelzenberg-M-D", "name": { "family": "Kelzenberg", "given": "Michael" }, "orcid": "0000-0002-6249-2827" }, { "id": "Biswas-S", "name": { "family": "Biswas", "given": "Souvik" } }, { "id": "Hunt-M-S", "name": { "family": "Hunt", "given": "Matthew S." } }, { "id": "Carbone-A", "name": { "family": "Carbone", "given": "Abigail" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "A new metal transfer process for van der Waals contacts to vertical Schottky-junction transition metal dichalcogenide photovoltaics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).\nThis is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. \n\nSubmitted 8 April 2019; Accepted 30 October 2019; Published 20 December 2019. \n\nWe thank S. Nam for the useful discussions. \n\nThis work was supported by the DOE \"Photonics at Thermodynamic Limits\" Energy Frontier Research Center under grant DE-SC0019140. C.M.W. and J.W. acknowledge support from the NSF Graduate Research Fellowship under grants 1745301 and 1144469. C.M.W. acknowledges fellowship support from the Resnick Sustainability Institute. \n\nAuthor contributions: C.M.W. fabricated the devices, performed the measurements, and performed the simulations. C.M.W., J.W., P.R.J., and S.B. developed the metal transfer technique. J.W. and P.R.J. assisted with the simulations. M.K. assisted with the solar simulator, absorption, and EQE measurements. M.S.H. and A.C. assisted with the TEM sample preparation and imaging. H.A.A. supervised all the experiments, calculations, and data collection. All authors contributed to the data interpretation, presentation, and writing of the manuscript. \n\nThe authors declare that they have no competing interests. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors.\n\n

Published - aax6061.pdf

Submitted - 1903.08191.pdf

Supplemental Material - aax6061_SM.pdf

", "abstract": "Two-dimensional transition metal dichalcogenides are promising candidates for ultrathin optoelectronic devices due to their high absorption coefficients and intrinsically passivated surfaces. To maintain these near-perfect surfaces, recent research has focused on fabricating contacts that limit Fermi-level pinning at the metal-semiconductor interface. Here, we develop a new, simple procedure for transferring metal contacts that does not require aligned lithography. Using this technique, we fabricate vertical Schottky-junction WS\u2082 solar cells, with Ag and Au as asymmetric work function contacts. Under laser illumination, we observe rectifying behavior and open-circuit voltage above 500 mV in devices with transferred contacts, in contrast to resistive behavior and open-circuit voltage below 15 mV in devices with evaporated contacts. One-sun measurements and device simulation results indicate that this metal transfer process could enable high specific power vertical Schottky-junction transition metal dichalcogenide photovoltaics, and we anticipate that this technique will lead to advances for two-dimensional devices more broadly.", "date": "2019-12-20", "date_type": "published", "publication": "Science Advances", "volume": "5", "number": "12", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eaax6061", "id_number": "CaltechAUTHORS:20190513-082509112", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190513-082509112", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019140" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.aax6061", "pmcid": "PMC6924982", "primary_object": { "basename": "aax6061_SM.pdf", "url": "https://authors.library.caltech.edu/records/nfcn9-2a530/files/aax6061_SM.pdf" }, "related_objects": [ { "basename": "1903.08191.pdf", "url": "https://authors.library.caltech.edu/records/nfcn9-2a530/files/1903.08191.pdf" }, { "basename": "aax6061.pdf", "url": "https://authors.library.caltech.edu/records/nfcn9-2a530/files/aax6061.pdf" } ], "pub_year": "2019", "author_list": "Went, Cora M.; Wong, Joeson; et al." }, { "id": "https://authors.library.caltech.edu/records/z93er-v9p62", "eprint_id": 100501, "eprint_status": "archive", "datestamp": "2023-08-19 19:10:34", "lastmod": "2023-10-18 20:56:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jongaramrungruang-Siraput", "name": { "family": "Jongaramrungruang", "given": "Siraput" }, "orcid": "0000-0002-2477-2043" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Matheou-Georgios", "name": { "family": "Matheou", "given": "Georgios" }, "orcid": "0000-0003-4024-4571" }, { "id": "Thorpe-Andrew-K", "name": { "family": "Thorpe", "given": "Andrew K." }, "orcid": "0000-0001-7968-5433" }, { "id": "Thompson-David-R", "name": { "family": "Thompson", "given": "David R." }, "orcid": "0000-0003-1100-7550" }, { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Duren-Riley-M", "name": { "family": "Duren", "given": "Riley M." }, "orcid": "0000-0003-4723-5280" } ] }, "title": "Towards accurate methane point-source quantification from high-resolution 2-D plume imagery", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Author(s). This work is distributed under the Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 25 Apr 2019 \u2013 Discussion started: 06 May 2019 \u2013 Revised: 18 Oct 2019 \u2013 Accepted: 22 Oct 2019 \u2013 Published: 17 Dec 2019. \n\nThis work is part of SJ's NASA Earth and Space Science Fellowship (NESSF). We acknowledge the Resnick Sustainability Institute at Caltech for their kind support with computing resources. This work was supported in part by NASA's Carbon Monitoring System (CMS) Prototype Methane Monitoring System for California. We also thank NASA's Earth Science Division, particularly Jack Kaye, for continued support of AVIRIS-NG and HyTES methane science. Additional funding was provided to JPL by the California Air Resources Board under ARB-NASA agreement 15RD028 and Space Act agreement 82-19863 as well as the California Energy Commission under CEC-500-15-004. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NNN12AA01C). We thank the AVIRIS-NG team and colleagues at the Pacific Gas and Electric Company for their support for controlled-release experiments. \n\nCode and data availability: AVIRIS-NG data are publicly available via the AVIRIS-NG data portal by JPL via https://aviris-ng.jpl.nasa.gov/benchmark_methane_data.html (last access: 4 December 2019); HyTES L2 and L3 data are available for ordering free of charge from the HyTES data portal by JPL at https://hytes.jpl.nasa.gov/order (last access: 4 December 2019). \n\nAuthor contributions: SJ performed the analysis and wrote the paper, with the overall research objectives advised by CF. GM ran the LES model, provided output, and guided the analysis; AT, RD, EK, and DT provided the AVIRIS-NG and HyTES datasets and supported the writing and data analysis. \n\nThe authors declare that they have no conflict of interest. \n\nThis research has been supported by NASA (grant no. 80NSSC18K1350). \n\nReview statement: This paper was edited by Christoph Kiemle and reviewed by two anonymous referees.\n\n

Published - amt-12-6667-2019.pdf

", "abstract": "Methane is the second most important anthropogenic greenhouse gas in the Earth climate system but emission quantification of localized point sources has been proven challenging, resulting in ambiguous regional budgets and source category distributions. Although recent advancements in airborne remote sensing instruments enable retrievals of methane enhancements at an unprecedented resolution of 1\u20135\u2009m at regional scales, emission quantification of individual sources can be limited by the lack of knowledge of local wind speed. Here, we developed an algorithm that can estimate flux rates solely from mapped methane plumes, avoiding the need for ancillary information on wind speed. The algorithm was trained on synthetic measurements using large eddy simulations under a range of background wind speeds of 1\u201310\u2009m\u2009s\u207b\u00b9 and source emission rates ranging from 10 to 1000\u2009kg\u2009h\u207b\u00b9. The surrogate measurements mimic plume mapping performed by the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) and provide an ensemble of 2-D snapshots of column methane enhancements at 5\u2009m spatial resolution. We make use of the integrated total methane enhancement in each plume, denoted as integrated methane enhancement (IME), and investigate how this IME relates to the actual methane flux rate. Our analysis shows that the IME corresponds to the flux rate nonlinearly and is strongly dependent on the background wind speed over the plume. We demonstrate that the plume width, defined based on the plume angular distribution around its main axis, provides information on the associated background wind speed. This allows us to invert source flux rate based solely on the IME and the plume shape itself. On average, the error estimate based on randomly generated plumes is approximately 30\u2009% for an individual estimate and less than 10\u2009% for an aggregation of 30 plumes. A validation against a natural gas controlled-release experiment agrees to within 32\u2009%, supporting the basis for the applicability of this technique to quantifying point sources over large geographical areas in airborne field campaigns and future space-based observations.", "date": "2019-12-17", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "12", "number": "12", "publisher": "European Geosciences Union", "pagerange": "6667-6681", "id_number": "CaltechAUTHORS:20200103-110843259", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200103-110843259", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Earth and Space Science Fellowship" }, { "agency": "California Air Resources Board", "grant_number": "15RD028" }, { "agency": "NASA", "grant_number": "82-19863" }, { "agency": "California Energy Commission", "grant_number": "CEC-500-15-004" }, { "agency": "NASA", "grant_number": "NNN12AA01C" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "80NSSC18K1350" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-12-6667-2019", "primary_object": { "basename": "amt-12-6667-2019.pdf", "url": "https://authors.library.caltech.edu/records/z93er-v9p62/files/amt-12-6667-2019.pdf" }, "pub_year": "2019", "author_list": "Jongaramrungruang, Siraput; Frankenberg, Christian; et al." }, { "id": "https://authors.library.caltech.edu/records/m2xjr-7db67", "eprint_id": 99417, "eprint_status": "archive", "datestamp": "2023-08-19 19:06:37", "lastmod": "2023-10-18 18:17:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Lixue", "name": { "family": "Cheng", "given": "Lixue" }, "orcid": "0000-0002-7329-0585" }, { "id": "Kovachki-N-B", "name": { "family": "Kovachki", "given": "Nikola B." }, "orcid": "0000-0002-3650-2972" }, { "id": "Welborn-M-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Regression-clustering for Improved Accuracy and Training Cost with Molecular-Orbital-Based Machine Learning", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: September 4, 2019; Published: October 22, 2019. \n\nThis work emerged from a CMS 273 class project at Caltech that also involved Dmitry Burov, Jialin Song, Ying Shi Teh, and Dr. Tamara Husch, as well as Professors Kaushik Bhattacharya and Richard Murray; we thank these individuals for their ideas and contributions. \n\nThis work is supported by the US Air Force Office of Scientific Research (AFOSR) grant FA9550-17-1-0102. M.W. acknowledges a postdoctoral fellowship from the Resnick Sustainability Institute. N.B.K. is supported, in part, by the US National Science Foundation (NSF) grant DMS 1818977, the US Office of Naval Research (ONR) grant N00014-17-1-2079, and the US Army Research Office (ARO) grant W911NF-12-2-0022. Computational resources were provided by the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the DOE Office of Science under contract DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1909.02041.pdf

", "abstract": "Machine learning (ML) in the representation of molecular-orbital-based (MOB) features has been shown to be an accurate and transferable approach to the prediction of post-Hartree-Fock correlation energies. Previous applications of MOB-ML employed Gaussian Process Regression (GPR), which provides good prediction accuracy with small training sets; however, the cost of GPR training scales cubically with the amount of data and becomes a computational bottleneck for large training sets. In the current work, we address this problem by introducing a clustering/regression/classification implementation of MOB-ML. In a first step, regression clustering (RC) is used to partition the training data to best fit an ensemble of linear regression (LR) models; in a second step, each cluster is regressed independently, using either LR or GPR; and in a third step, a random forest classifier (RFC) is trained for the prediction of cluster assignments based on MOB feature values. Upon inspection, RC is found to recapitulate chemically intuitive groupings of the frontier molecular orbitals, and the combined RC/LR/RFC and RC/GPR/RFC implementations of MOB-ML are found to provide good prediction accuracy with greatly reduced wall-clock training times. For a dataset of thermalized (350 K) geometries of 7211 organic molecules of up to seven heavy atoms (QM7b-T), both RC/LR/RFC and RC/GPR/RFC reach chemical accuracy (1 kcal/mol prediction error) with only 300 training molecules, while providing 35000-fold and 4500-fold reductions in the wall-clock training time, respectively, compared to MOB-ML without clustering. The resulting models are also demonstrated to retain transferability for the prediction of large-molecule energies with only small-molecule training data. Finally, it is shown that capping the number of training datapoints per cluster leads to further improvements in prediction accuracy with negligible increases in wall-clock training time.", "date": "2019-12-10", "date_type": "published", "publication": "Journal of Chemical Theory and Computation", "volume": "15", "number": "12", "publisher": "American Chemical Society", "pagerange": "6668-6677", "id_number": "CaltechAUTHORS:20191023-150600399", "issn": "1549-9618", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191023-150600399", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-17-1-0102" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMS-1818977" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-17-1-2079" }, { "agency": "Army Research Laboratory", "grant_number": "W911NF-12-2-0022" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jctc.9b00884", "primary_object": { "basename": "1909.02041.pdf", "url": "https://authors.library.caltech.edu/records/m2xjr-7db67/files/1909.02041.pdf" }, "pub_year": "2019", "author_list": "Cheng, Lixue; Kovachki, Nikola B.; et al." }, { "id": "https://authors.library.caltech.edu/records/5rrhw-jse87", "eprint_id": 98411, "eprint_status": "archive", "datestamp": "2023-08-22 03:06:30", "lastmod": "2023-10-18 17:20:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Xiaomei", "name": { "family": "Zeng", "given": "Xiaomei" } }, { "id": "Arai-Noriaki", "name": { "family": "Arai", "given": "Noriaki" }, "orcid": "0000-0002-3040-2997" }, { "id": "Faber-K-T", "name": { "family": "Faber", "given": "Katherine T." }, "orcid": "0000-0001-6585-2536" } ] }, "title": "Robust Cellular Shape-Memory Ceramics via Gradient\u2010Controlled Freeze Casting", "ispublished": "pub", "full_text_status": "public", "keywords": "cellular structures; ice templating; martensitic transformation; porous ceramics; shape\u2010memory ceramics", "note": "\u00a9 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n \nIssue Online: 19 December 2019; Version of Record online: 23 September 2019; Accepted manuscript online: 31 August 2019; Manuscript revised: 16 August 2019; Manuscript received: 11 April 2019. \n\nFunding Information: Resnick Sustainability Institute at Caltech; National Science Foundation. Grant Number: DMR-1411218.\n\n

Supplemental Material - adem201900398-sup-0001-suppdata-s1.docx

", "abstract": "Shape\u2010memory ceramics offer promise for applications like actuation and energy damping, due to their unique properties of high specific strength, high ductility, light weight and inertness in harsh environments. To date, shape\u2010memory behavior in ceramics is limited to micro/submicro\u2010scale pillars and particles to circumvent the longstanding problem of transformation\u2010induced fracture which occurs readily in bulk polycrystalline specimens. The challenge, therefore, lies in the realization of shape\u2010memory properties in bulk ceramics, which requires careful design of three\u2010dimensional structures that locally mimic pillar structures. In this work, it is demonstrated that with a gradient\u2010controlled freeze\u2010casting approach, honeycomb\u2010like cellular structures can be fabricated with thin and directionally aligned walls to facilitate martensitic transformation under compression without fracture. With this approach, robust bulk shape\u2010memory ceramics have been demonstrated in a highly porous structure with strengths under compressive stresses of 25 MPa and strains up to 7.5%.", "date": "2019-12", "date_type": "published", "publication": "Advanced Engineering Materials", "volume": "21", "number": "12", "publisher": "Wiley", "pagerange": "Art. No. 1900398", "id_number": "CaltechAUTHORS:20190904-112355921", "issn": "1438-1656", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190904-112355921", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1411218" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/adem.201900398", "primary_object": { "basename": "adem201900398-sup-0001-suppdata-s1.docx", "url": "https://authors.library.caltech.edu/records/5rrhw-jse87/files/adem201900398-sup-0001-suppdata-s1.docx" }, "pub_year": "2019", "author_list": "Zeng, Xiaomei; Arai, Noriaki; et al." }, { "id": "https://authors.library.caltech.edu/records/8gaqr-e8y86", "eprint_id": 98794, "eprint_status": "archive", "datestamp": "2023-08-22 03:01:05", "lastmod": "2023-10-18 17:38:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "In-situ Nanostructuring and Stabilization of Polycrystalline Copper by an Organic Salt Additive Promotes Electrocatalytic CO\u2082 Reduction to Ethylene", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon Dioxide; electrocatalysis; ethylene; nanocubes; Stability", "note": "\u00a9 2019 Wiley-\u2010VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nAccepted manuscript online: 19 September 2019; Manuscript accepted: 19 September 2019; Manuscript revised: 13 August 2019; Manuscript received: 25 June 2019. \n\nNMR, AFM and XPS, SEM and EDX measurements were collected at the NMR Facility (Division of CCE), the Molecular Materials Research Center (Beckman Institute) and the Analytic Facilities (Division of Geological and Planetary Sciences) of the California Institute of Technology, respectively. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and Marie Curie Fellowship H2020-MSCA-IF-2017 (793471) (A.T.). J.C.P. acknowledges additional support from the Resnick Sustainability Institute at Caltech. \n\nThe authors declare no conflict of interest.\n\n

Supplemental Material - anie201907935-s1-supportinginformation.pdf

", "abstract": "Bridging homogeneous molecular systems with heterogeneous catalysts is a promising approach for the development of new electrodes, combining the advantages of both approaches. In the context of CO\u2082 electroreduction, molecular enhancement of planar copper electrodes has enabled promising advancement towards high Faradaic efficiencies for multicarbon products. Besides, nanostructured copper electrodes have also demonstrated enhanced performance at comparatively low overpotentials. Herein, we report a novel and convenient method for nanostructuring copper electrodes using N,N'\u2010ethylene\u2010phenanthrolinium dibromide as molecular additive. Selectivities up to 70% for C\u2265\u2082 products are observed for more than 40 h without significant change in the surface morphology. Mechanistic studies reveal several roles for the organic additive, including: the formation of cube\u2010like nanostructures by corrosion of the copper surface, the stabilization of these nanostructures during electrocatalysis by formation of a protective organic layer, and the promotion of C\u2265\u2082 products.", "date": "2019-11-18", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "58", "number": "47", "publisher": "Wiley", "pagerange": "16952-16958", "id_number": "CaltechAUTHORS:20190923-102748967", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190923-102748967", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Marie Curie Fellowship", "grant_number": "H2020-MSCA-IF-2017" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201907935", "primary_object": { "basename": "anie201907935-s1-supportinginformation.pdf", "url": "https://authors.library.caltech.edu/records/8gaqr-e8y86/files/anie201907935-s1-supportinginformation.pdf" }, "pub_year": "2019", "author_list": "Thevenon, Arnaud; Rosas-Hern\u00e1ndez, Alonso; et al." }, { "id": "https://authors.library.caltech.edu/records/tv9t3-jzr21", "eprint_id": 99254, "eprint_status": "archive", "datestamp": "2023-08-22 02:52:50", "lastmod": "2023-10-18 18:10:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moodie-A-J", "name": { "family": "Moodie", "given": "Andrew J." }, "orcid": "0000-0002-6745-036X" }, { "id": "Nittrouer-J-A", "name": { "family": "Nittrouer", "given": "Jeffrey A." }, "orcid": "0000-0002-4762-0157" }, { "id": "Ma-Hongbo", "name": { "family": "Ma", "given": "Hongbo" }, "orcid": "0000-0002-6017-8113" }, { "id": "Carlson-B-N", "name": { "family": "Carlson", "given": "Brandee N." }, "orcid": "0000-0002-5369-9746" }, { "id": "Chadwick-A-J", "name": { "family": "Chadwick", "given": "Austin J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "Michael P." }, "orcid": "0000-0002-5701-0504" }, { "id": "Parker-G", "name": { "family": "Parker", "given": "Gary" }, "orcid": "0000-0001-5973-5296" } ] }, "title": "Modeling deltaic lobe\u2010building cycles and channel avulsions for the Yellow River delta, China", "ispublished": "pub", "full_text_status": "public", "keywords": "river avulsion; lowland deltas; backwater; deltaic lobe", "note": "\u00a9 2019 American Geophysical Union. \n\nReceived 21 JUN 2019; Accepted 20 SEP 2019; Accepted article online 15 OCT 2019. \n\nA. J. M., J. A. N., H. M., B. N. C., A. J. C., M. P. L., and G. P. acknowledge support from the National Science Foundation (NSF) EAR\u20101427262 Coastal SEES grant. A. J. M. was supported by a NSF Graduate Research Fellowship under Grant 1842494. A. J. C. was supported by the Resnick Sustainability Institute at Caltech. G. P. was supported by the NSF Grant EAR\u20101209402. The authors sincerely thank Vamsi Ganti and two anonymous reviewers for their thoughtful critique of this manuscript. The model code and supporting data can be obtained online (https://github.com/amoodie/paper_resources/Moodie_deltaiclobebuilding).\n\n

Published - Moodie_et_al-2019-Journal_of_Geophysical_Research__Earth_Surface.pdf

Supplemental Material - 2019jf005220-sup-0001-text_si-s01.pdf

", "abstract": "River deltas grow by repeating cycles of lobe development punctuated by channel avulsions, so that over time, lobes amalgamate to produce a composite landform. Existing models have shown that backwater hydrodynamics are important in avulsion dynamics, but the effect of lobe progradation on avulsion frequency and location has yet to be explored. Herein, a quasi\u20102\u2010D numerical model incorporating channel avulsion and lobe development cycles is developed. The model is validated by the well\u2010constrained case of a prograding lobe on the Yellow River delta, China. It is determined that with lobe progradation, avulsion frequency decreases, and avulsion length increases, relative to conditions where a delta lobe does not prograde. Lobe progradation lowers the channel bed gradient, which results in channel aggradation over the delta topset that is focused farther upstream, shifting the avulsion location upstream. Furthermore, the frequency and location of channel avulsions are sensitive to the threshold in channel bed superelevation that triggers an avulsion. For example, avulsions occur less frequently with a larger superelevation threshold, resulting in greater lobe progradation and avulsions that occur farther upstream. When the delta lobe length prior to avulsion is a moderate fraction of the backwater length (0.3\u20130.5L_b), the interplay between variable water discharge and lobe progradation together set the avulsion location, and a model capturing both processes is necessary to predict avulsion timing and location. While this study is validated by data from the Yellow River delta, the numerical framework is rooted in physical relationships and can therefore be extended to other deltaic systems.", "date": "2019-11", "date_type": "published", "publication": "Journal of Geophysical Research. Earth Surface", "volume": "124", "number": "11", "publisher": "American Geophysical Union", "pagerange": "2438-2462", "id_number": "CaltechAUTHORS:20191014-133706256", "issn": "2169-9003", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191014-133706256", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1842494" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "EAR-1209402" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019jf005220", "primary_object": { "basename": "2019jf005220-sup-0001-text_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/tv9t3-jzr21/files/2019jf005220-sup-0001-text_si-s01.pdf" }, "related_objects": [ { "basename": "Moodie_et_al-2019-Journal_of_Geophysical_Research__Earth_Surface.pdf", "url": "https://authors.library.caltech.edu/records/tv9t3-jzr21/files/Moodie_et_al-2019-Journal_of_Geophysical_Research__Earth_Surface.pdf" } ], "pub_year": "2019", "author_list": "Moodie, Andrew J.; Nittrouer, Jeffrey A.; et al." }, { "id": "https://authors.library.caltech.edu/records/fycwy-bm347", "eprint_id": 98338, "eprint_status": "archive", "datestamp": "2023-08-22 02:44:53", "lastmod": "2023-10-18 17:16:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Drover-M-W", "name": { "family": "Drover", "given": "Marcus W." }, "orcid": "0000-0002-2186-1040" }, { "id": "Schild-D-J", "name": { "family": "Schild", "given": "Dirk J." } }, { "id": "Oyala-P-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Snapshots of a Migrating H-atom: Characterization of a Reactive Fe(III) Indenide Hydride and its Nearly Isoenergetic Ring-Protonated Fe(I) Isomer", "ispublished": "pub", "full_text_status": "public", "keywords": "electronic structure; iron; metalloradicals; Structure elucidation; alkene ligands", "note": "\u00a9 2019 WILEY\u2010VCH. \n\nManuscript received: July 22, 2019; Accepted manuscript online: August 29, 2019; Version of record online: September 18, 2019. \n\nThe authors are grateful to the Department of Energy for support via Grant No. DOE-0235032. The Caltech EPR facility was supported by the National Science Foundation via grant No. NSF MRI-153194, as well as the Dow Next Generation Educator Fund. The Beckman Institute is thanked for X-ray support. M.W.D. acknowledges NSERC (Banting PDF award to MWD), and M.W.D./D.J.S. thank the Resnick Sustainability Institute at Caltech for fellowships. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - anie.201909050.pdf

Supplemental Material - anie201909050-sup-0001-misc_information.pdf

", "abstract": "We report the characterization of an S = \u00bd iron \u03c0\u2010complex, [Fe(\u03b7^6\u2010IndH)(depe)]^+ (Ind = Indenide (C_9H_(7^\u2010_), depe = 1,2\u2010bis(diethylphosphino)ethane), which results via C\u2010H elimination from a transient Fe^(III) hydride, [Fe(\u03b7^3:\u03b7^2\u2010Ind)(depe)H]^+. Owing to weak M\u2010H/C\u2010H bonds, these species undergo proton\u2010coupled electron transfer (PCET) to release H_2 through bimolecular recombination. Mechanistic information, gained from stoichiometric as well as computational studies, reveal the open\u2010shell \u03c0\u2010arene complex to have a BDFE_(C\u2010H) value of \u2248 50 kcal mol^(\u20101), roughly equal to the BDFE_(Fe\u2010H) of its Fe^(III)\u2010H precursor (\u0394G^o \u2248 0 between them). Markedly, this reactivity differs from related Fe(\u03b7^5\u2010Cp/Cp^*) compounds, for which terminal Fe^(III)\u2010H cations are isolable and have been structurally characterized, highlighting the effect of a benzannulated (indene) ring. Overall, this study provides a structural, thermochemical, and mechanistic foundation for the characterization of indenide/indene PCET precursors and out\u2010lines a valuable approach for the differentiation of a ring\u2010 versus a metal\u2010 bound H\u2010atom by way of continuous\u2010wave (CW) and pulse EPR (HYSCORE) spectroscopic measurements.", "date": "2019-10-21", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "58", "number": "43", "publisher": "Wiley", "pagerange": "15504-15511", "id_number": "CaltechAUTHORS:20190829-111225922", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190829-111225922", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "NSF", "grant_number": "MRI-153194" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201909050", "primary_object": { "basename": "anie.201909050.pdf", "url": "https://authors.library.caltech.edu/records/fycwy-bm347/files/anie.201909050.pdf" }, "related_objects": [ { "basename": "anie201909050-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/fycwy-bm347/files/anie201909050-sup-0001-misc_information.pdf" } ], "pub_year": "2019", "author_list": "Drover, Marcus W.; Schild, Dirk J.; et al." }, { "id": "https://authors.library.caltech.edu/records/47dh5-zxn52", "eprint_id": 100162, "eprint_status": "archive", "datestamp": "2023-08-22 02:45:16", "lastmod": "2023-10-18 19:08:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Drover-M-W", "name": { "family": "Drover", "given": "Marcus W." }, "orcid": "0000-0002-2186-1040" }, { "id": "Schild-D-J", "name": { "family": "Schild", "given": "Dirk J." } }, { "id": "Oyala-P-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Snapshots of a Migrating H-Atom: Characterization of a Reactive Iron(III) Indenide Hydride and its Nearly Isoenergetic Ring-Protonated Iron(I) Isomer", "ispublished": "pub", "full_text_status": "public", "keywords": "HYSCORE; metalloradicals; PCET reactivity; pulse EPR; weak C\u2212H bonds", "note": "\u00a9 2019 Wiley\u2010VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nIssue Online: 14 October 2019; Version of Record online: 18 September 2019; Accepted manuscript online: 29 August 2019; Manuscript received: 22 July 2019. \n\nThe authors are grateful to the Department of Energy for support via Grant No. DOE\u20100235032. The Caltech EPR facility was supported by the National Science Foundation via grant No. NSF MRI\u2010153194, as well as the Dow Next Generation Educator Fund. The Beckman Institute is thanked for X\u2010ray support. M.W.D. acknowledges NSERC (Banting PDF award), and M.W.D./D.J.S thank the Resnick Sustainability Institute at Caltech for fellowships. \n\nThe authors declare no conflict of interest.\n\n

Supplemental Material - anie201909050-sup-0001-misc_information.pdf

", "abstract": "We report the characterization of an S=1/2 iron \u03c0\u2010complex, [Fe(\u03b7\u2076\u2010IndH)(depe)]\u207a (Ind=Indenide (C\u2089H\u2087\u207b), depe=1,2\u2010bis(diethylphosphino)ethane), which results via C\u2212H elimination from a transient Fe^(III) hydride, [Fe(\u03b7\u00b3:\u03b7\u00b2\u2010Ind)(depe)H]\u207a. Owing to weak M\u2212H/C\u2212H bonds, these species appear to undergo proton\u2010coupled electron transfer (PCET) to release H\u2082 through bimolecular recombination. Mechanistic information, gained from stoichiometric as well as computational studies, reveal the open\u2010shell \u03c0\u2010arene complex to have a BDFE_(C\u2010H) value of \u224850 kcal\u2009mol\u207b\u00b9, roughly equal to the BDFE_(Fe\u2010H) of its Fe^(III)\u2212H precursor (\u0394G\u00b0\u22480 between them). Markedly, this reactivity differs from related Fe(\u03b7\u2075\u2010Cp/Cp*) compounds, for which terminal Fe^(III)\u2212H cations are isolable and have been structurally characterized, highlighting the effect of a benzannulated ring (indene). Overall, this study provides a structural, thermochemical, and mechanistic foundation for the characterization of indenide/indene PCET precursors and outlines a valuable approach for the differentiation of a ring\u2010 versus a metal\u2010bound H\u2010atom by way of continuous\u2010wave (CW) and pulse EPR (HYSCORE) spectroscopic measurements.", "date": "2019-10-21", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "58", "number": "43", "publisher": "Wiley", "pagerange": "15504-15511", "id_number": "CaltechAUTHORS:20191203-101325731", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191203-101325731", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "NSF", "grant_number": "MRI\u2010153194" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201909050", "primary_object": { "basename": "anie201909050-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/47dh5-zxn52/files/anie201909050-sup-0001-misc_information.pdf" }, "pub_year": "2019", "author_list": "Drover, Marcus W.; Schild, Dirk J.; et al." }, { "id": "https://authors.library.caltech.edu/records/vqxvh-61f48", "eprint_id": 98409, "eprint_status": "archive", "datestamp": "2023-08-19 18:12:28", "lastmod": "2025-04-25 23:32:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Buss-J-A", "name": { "family": "Buss", "given": "Joshua A." }, "orcid": "0000-0002-3347-8583" }, { "id": "Bailey-G-A", "name": { "family": "Bailey", "given": "Gwendolyn A." }, "orcid": "0000-0002-6636-4128" }, { "id": "Oppenheim-Julius-J", "name": { "family": "Oppenheim", "given": "Julius" }, "orcid": "0000-0002-5988-0677" }, { "id": "VanderVelde-D-G", "name": { "family": "VanderVelde", "given": "David G." }, "orcid": "0000-0002-2907-0366" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "CO Coupling Chemistry of a Terminal Mo Carbide: Sequential Addition of Proton, Hydride, and CO Releases Ethenone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: July 22, 2019; Published: September 3, 2019. \n\nWe thank Larry Henling and Mike Takase for invaluable crystallographic assistance. J.A.B. is grateful for an NSF graduate research fellowship, G.A.B. for NSERC and Resnick Sustainability Institute fellowships, and J.O. for an Ernest H. Swift Summer Undergraduate Research Fellowship. We thank the NSF (CHE-1800501), the Dow Next Generation Education Fund (instrumentation), and Caltech for funding. The computational studies were supported by the NSF (CBET-1805022). \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja9b07743_si_001.pdf

Supplemental Material - ja9b07743_si_002.cif

", "abstract": "The mechanism originally proposed by Fischer and Tropsch for carbon monoxide (CO) hydrogenative catenation involves C\u2013C coupling from a carbide-derived surface methylidene. A single molecular system capable of capturing these complex chemical steps is hitherto unknown. Herein, we demonstrate the sequential addition of proton and hydride to a terminal Mo carbide derived from CO. The resulting anionic methylidene couples with CO (1 atm) at low temperature (\u221278 \u00b0C) to release ethenone. Importantly, the synchronized delivery of two reducing equivalents and an electrophile, in the form of a hydride (H\u2013 = 2e\u2013 + H+), promotes alkylidene formation from the carbyne precursor and enables coupling chemistry, under conditions milder than those previously described with strong one-electron reductants and electrophiles. Thermodynamic measurements bracket the hydricity and acidity requirements for promoting methylidene formation from carbide as energetically viable relative to the heterolytic cleavage of H2. Methylidene formation prior to C\u2013C coupling proves critical for organic product release, as evidenced by direct carbide carbonylation experiments. Spectroscopic studies, a monosilylated model system, and Quantum Mechanics computations provide insight into the mechanistic details of this reaction sequence, which serves as a rare model of the initial stages of the Fischer\u2013Tropsch synthesis.", "date": "2019-10-02", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "39", "publisher": "American Chemical Society", "pagerange": "15664-15674", "id_number": "CaltechAUTHORS:20190904-110429088", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190904-110429088", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "NSF", "grant_number": "CHE-1800501" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "NSF", "grant_number": "CBET-1805022" } ] }, "other_numbering_system": { "items": [ { "id": "1350", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.9b07743", "primary_object": { "basename": "ja9b07743_si_001.pdf", "url": "https://authors.library.caltech.edu/records/vqxvh-61f48/files/ja9b07743_si_001.pdf" }, "related_objects": [ { "basename": "ja9b07743_si_002.cif", "url": "https://authors.library.caltech.edu/records/vqxvh-61f48/files/ja9b07743_si_002.cif" } ], "pub_year": "2019", "author_list": "Buss, Joshua A.; Bailey, Gwendolyn A.; et al." }, { "id": "https://authors.library.caltech.edu/records/gpaqf-ec237", "eprint_id": 95817, "eprint_status": "archive", "datestamp": "2023-08-22 02:38:43", "lastmod": "2023-10-23 17:01:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Shaoqing", "name": { "family": "Chen", "given": "Shaoqing" }, "orcid": "0000-0002-6700-292X" }, { "id": "Tan-Yiqi", "name": { "family": "Tan", "given": "Yiqi" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" } ] }, "title": "Direct and embodied energy-water-carbon nexus at an inter-regional scale", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Energy-water-carbon nexus; Inter-regional input-output model; Nexus flows; Footprint intensity", "note": "\u00a9 2019 Elsevier Ltd. \n\nReceived 17 March 2019, Revised 14 May 2019, Accepted 20 May 2019, Available online 27 May 2019.", "abstract": "Energy, water and carbon flows are highly intertwined in economy and influence urban and regional sustainability. Few insights have been acquired for energy-water-carbon nexus at inter-regional scale considering both in- and trans-boundary flows. Here we propose an interactive framework to assess inter-regional energy-water-carbon nexus, encapsulating both direct nexus flows within territory and nexus flows embodied in final consumption. An inter-regional input-output model is established to account for energy-related water footprint, water-related energy footprint and water-related carbon footprint from a consumption-based perspective. Using Guangdong-Hong Kong as a case study, we find that though these nexus footprints contribute a small fraction of the total energy, water and carbon footprints of both regions in 2012, their impacts should not be neglected due to higher intensities. The direct intensities of water-related energy and water-related carbon are more than 2 times higher than the total energy and carbon intensities, while their embodied intensities are over 6 times higher. Inter-regional trade plays an important role in controlling energy-water-carbon nexus of both sides. About 29\u201344% of the consumption-based nexus footprints of Hong Kong's consumption are outsourced to Guangdong and other regions, while 21\u201324% of Guangdong's footprints are from production elsewhere. These are strong signals showing the importance of managing energy-water-carbon nexus on a cross-border and fully-interactive basis.", "date": "2019-10-01", "date_type": "published", "publication": "Applied Energy", "volume": "251", "publisher": "Elsevier", "pagerange": "Art. No. 113401", "id_number": "CaltechAUTHORS:20190528-112145156", "issn": "0306-2619", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190528-112145156", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "71704015" }, { "agency": "Natural Science Funds for Distinguished Young Scholar of Guangdong Province", "grant_number": "2018B030306032" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apenergy.2019.113401", "pub_year": "2019", "author_list": "Chen, Shaoqing; Tan, Yiqi; et al." }, { "id": "https://authors.library.caltech.edu/records/9fzfa-c4k85", "eprint_id": 91339, "eprint_status": "archive", "datestamp": "2023-08-19 17:55:16", "lastmod": "2023-10-19 22:25:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Suh-Myoung-Gyun", "name": { "family": "Suh", "given": "Myoung-Gyun" }, "orcid": "0000-0002-9527-0585" }, { "id": "Vahala-K-J", "name": { "family": "Vahala", "given": "Kerry" }, "orcid": "0000-0003-1783-1380" } ] }, "title": "Microresonator soliton dual-comb imaging", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement. \n\nReceived 8 April 2019; revised 5 July 2019; accepted 24 July 2019 (Doc. ID 364448); published 27 August 2019. \n\nThe authors thank Taeyoon Jeon and Chengmingyue Li for helpful discussions on the flow-cell experiment. C. B. gratefully acknowledges support from a Postdoctoral Fellowship from the Resnick Institute at Caltech. \n\nFunding: Air Force Office of Scientific Research (FA9550-18-1-0353); Resnick Sustainability Institute for Science, Energy and Sustainability, California Institute of Technology.\n\n

Published - optica-6-9-1110.pdf

Submitted - 1809.09766.pdf

", "abstract": "Fast-responding detector arrays are commonly used for imaging rapidly changing scenes. Besides array detectors, a single-pixel detector combined with a broadband optical spectrum can also be used for rapid imaging by mapping the spectrum into a spatial coordinate grid and then rapidly measuring the spectrum. Here, optical frequency combs generated from high-Q silica microresonators are used to implement this method. The microcomb is dispersed in two spatial dimensions to measure a test target. The target-encoded spectrum is then measured by multi-heterodyne beating with another microcomb having a slightly different repetition rate, enabling an imaging frame rate up to 200 kHz and fill rates as high as 48 megapixels/s. The system is used to monitor the flow of microparticles in a fluid cell. Microcombs in combination with a monolithic waveguide grating array imager could greatly magnify these results by combining the spatial parallelism of detector arrays with spectral parallelism of optics.", "date": "2019-09-20", "date_type": "published", "publication": "Optica", "volume": "6", "number": "9", "publisher": "Optical Society of America", "pagerange": "1110-1116", "id_number": "CaltechAUTHORS:20181129-145913477", "issn": "2334-2536", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181129-145913477", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0353" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1364/OPTICA.6.001110", "primary_object": { "basename": "1809.09766.pdf", "url": "https://authors.library.caltech.edu/records/9fzfa-c4k85/files/1809.09766.pdf" }, "related_objects": [ { "basename": "optica-6-9-1110.pdf", "url": "https://authors.library.caltech.edu/records/9fzfa-c4k85/files/optica-6-9-1110.pdf" } ], "pub_year": "2019", "author_list": "Bao, Chengying; Suh, Myoung-Gyun; et al." }, { "id": "https://authors.library.caltech.edu/records/tcg2k-gh898", "eprint_id": 96453, "eprint_status": "archive", "datestamp": "2023-08-19 17:23:05", "lastmod": "2023-10-20 21:11:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bevilacqua-S-C", "name": { "family": "Bevilacqua", "given": "Sarah C." }, "orcid": "0000-0002-6834-7145" }, { "id": "Pham-Kim-H", "name": { "family": "Pham", "given": "Kim H." } }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Effect of the Electrolyte Solvent on Redox Processes in Mg\u2013S Batteries", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: March 27, 2019; Published: June 14, 2019. \n\nFinancial support from Caltech and the Dow Next Generation Educator Fund is gratefully acknowledged. S.C.B. acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. K.H.P. acknowledges funding from the Johnson & Johnson WAVE program at Caltech. The authors thank Charles J. Hansen and Dr. Andrew J. Martinolich for assistance in preparing MgS. The authors thank Dr. David Vander Velde for assistance in the collection of NMR spectra. NMR spectra were obtained on a spectrometer supported by the NIH (Grant RR027690).\n\n

Supplemental Material - ic9b00891_si_001.pdf

", "abstract": "Mg\u2013S batteries are attractive for next-generation energy storage because of their high theoretical capacity and low cost. The foremost challenge in Mg\u2013S batteries is designing electrolytes that support reversible electrochemistry at both electrodes. Here, we target a solution-mediated reduction pathway for the S_8 cathode by tailoring the electrolyte solvent. Varying the solvent in Mg-based systems is complicated because of the active nature of the solvent in solvating Mg^(2+) and the complex dynamics of electrolyte\u2013Mg interfaces. To understand the effect of the solvent on the S_8 reduction processes in the Mg\u2013S cell, the magnesium\u2013aluminum chloride complex (MACC) electrolyte was prepared in different ethereal solvents. Reversible Mg electrodeposition is demonstrated in the MACC electrolyte in several solvent systems. The electrodeposition overpotentials and current densities are found to vary with the solvent, suggesting that the solvent plays a noninnocent role in the electrochemical processes at the Mg interface. Mg\u2013S cells are prepared with the electrolytes to understand how the solvent affects the reduction of S_8. A reductive wave is present in all linear-sweep voltammograms, and the peak potential varies with the solvent. The peak potential is approximately 0.8 V versus Mg/Mg^(2+), lower than the expected reduction potential of 1.7 V. We rule out passivation of the Mg anode as the cause for the low voltage peak potential, making processes at the S8 cathode the likely culprit. The ability to oxidize MgS with the MACC electrolyte is also examined, and we find that the oxidation current can be attributed to side reactions at the C\u2013electrolyte interface.", "date": "2019-08-19", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "58", "number": "16", "publisher": "American Chemical Society", "pagerange": "10472-10482", "id_number": "CaltechAUTHORS:20190614-153313156", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190614-153313156", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Johnson and Johnson" }, { "agency": "NIH", "grant_number": "RR027690" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.9b00891", "primary_object": { "basename": "ic9b00891_si_001.pdf", "url": "https://authors.library.caltech.edu/records/tcg2k-gh898/files/ic9b00891_si_001.pdf" }, "pub_year": "2019", "author_list": "Bevilacqua, Sarah C.; Pham, Kim H.; et al." }, { "id": "https://authors.library.caltech.edu/records/q468e-dwg50", "eprint_id": 95433, "eprint_status": "archive", "datestamp": "2023-08-19 17:19:44", "lastmod": "2023-10-20 20:13:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Sebastian-J-R", "name": { "family": "Lee", "given": "Sebastian J. R." }, "orcid": "0000-0001-7006-9378" }, { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Analytical Gradients for Projection-Based Wavefunction-in-DFT Embedding", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published under license by AIP Publishing. \n\nSubmitted: 13 May 2019; Accepted: 3 July 2019; Published Online: 9 August 2019. \n\nWe thank Matthew Welborn for helpful discussions. This material is based on the work supported by the U.S. Army Research Laboratory under Grant No. W911NF-12-2-0023 (S.J.R.L.). S.J.R.L. thanks the Caltech Resnick Sustainability Institute for a graduate fellowship. T.F.M. and F.R.M. acknowledge joint support from the DOE (Award No. DEFOA-0001912), and F.R.M. acknowledges support from the Engineering and Physical Sciences Research Council for funding (No. EP/M013111/1).\n\n

Published - 1.5109882.pdf

Submitted - 1903.05830.pdf

Supplemental Material - Supp_material.zip

", "abstract": "Projection-based embedding provides a simple, robust, and accurate approach for describing a small part of a chemical system at the level of a correlated wavefunction (WF) method, while the remainder of the system is described at the level of density functional theory (DFT). Here, we present the derivation, implementation, and numerical demonstration of analytical nuclear gradients for projection-based wavefunction-in-density functional theory (WF-in-DFT) embedding. The gradients are formulated in the Lagrangian framework to enforce orthogonality, localization, and Brillouin constraints on the molecular orbitals. An important aspect of the gradient theory is that WF contributions to the total WF-in-DFT gradient can be simply evaluated using existing WF gradient implementations without modification. Another simplifying aspect is that Kohn-Sham (KS) DFT contributions to the projection-based embedding gradient do not require knowledge of the WF calculation beyond the relaxed WF density. Projection-based WF-in-DFT embedding gradients are thus easily generalized to any combination of WF and KS-DFT methods. We provide a numerical demonstration of the method for several applications, including a calculation of a minimum energy pathway for a hydride transfer in a cobalt-based molecular catalyst using the nudged-elastic-band method at the coupled-cluster single double-in-DFT level of theory, which reveals large differences from the transition state geometry predicted using DFT.", "date": "2019-08-14", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "151", "number": "6", "publisher": "American Institute of Physics", "pagerange": "Art. No. 064112", "id_number": "CaltechAUTHORS:20190513-111036074", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190513-111036074", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-12-2-0023" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FOA-0001912" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.5109882", "primary_object": { "basename": "1.5109882.pdf", "url": "https://authors.library.caltech.edu/records/q468e-dwg50/files/1.5109882.pdf" }, "related_objects": [ { "basename": "1903.05830.pdf", "url": "https://authors.library.caltech.edu/records/q468e-dwg50/files/1903.05830.pdf" }, { "basename": "Supp_material.zip", "url": "https://authors.library.caltech.edu/records/q468e-dwg50/files/Supp_material.zip" } ], "pub_year": "2019", "author_list": "Lee, Sebastian J. R.; Ding, Feizhi; et al." }, { "id": "https://authors.library.caltech.edu/records/2ztcn-nwy40", "eprint_id": 96668, "eprint_status": "archive", "datestamp": "2023-08-22 02:16:31", "lastmod": "2025-04-23 19:07:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Arky-Qin", "name": { "family": "Yang", "given": "Arky" } }, { "id": "Blancon-J-C", "name": { "family": "Blancon", "given": "Jean-Christophe" } }, { "id": "Jiang-Wei", "name": { "family": "Jiang", "given": "Wei" } }, { "id": "Zhang-Hao", "name": { "family": "Zhang", "given": "Hao" } }, { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Yan-Ellen-X", "name": { "family": "Yan", "given": "Ellen" }, "orcid": "0000-0003-3252-790X" }, { "id": "Lin-Yi-Rung", "name": { "family": "Lin", "given": "Yi-Rung" } }, { "id": "Crochet-J-J", "name": { "family": "Crochet", "given": "Jared" } }, { "id": "Kanatzidis-M-G", "name": { "family": "Kanatzidis", "given": "Mercouri G." }, "orcid": "0000-0003-2037-4168" }, { "id": "Jariwala-D", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Low-Tony", "name": { "family": "Low", "given": "Tony" }, "orcid": "0000-0002-5759-5899" }, { "id": "Mohite-A-D", "name": { "family": "Mohite", "given": "Aditya D." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Giant Enhancement of Photoluminescence Emission in WS_2-2D Perovskite Heterostructures", "ispublished": "pub", "full_text_status": "public", "keywords": "Two dimensional materials; perovskite; transition metal dichalcogenide; heterostructure; interface; photoluminescence", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: December 22, 2018; Revised: June 10, 2019; Published: June 24, 2019. \n\nThis work is part of the \"Photonics at Thermodynamic Limits\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0019140. We also acknowledge Northrop Grumman for financial support of instrumentation. A.Y. and J.W. acknowledge financial support from a Resnick Institute Fellowship. A.D.M. and J.-C.B. acknowledge support by the DOE-EERE DE-FOA-0001647 program. MGK thanks ONR for support on investigating the stability of 2D perovskites (N00014-17-1-2231). We acknowledge support from the Beckman Institute of the California Institute of Technology to the Molecular Materials Research Center. We are grateful to Prof. George R. Rossman for technical help, discussions, and support. We thank Prof. Jacky Even for useful discussions concerning the perovskite surface termination. \n\nAuthor Contributions: A.Y. and J.-C.B. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl8b05105_si_001.pdf

", "abstract": "Transition metal dichalcogenides (TMDCs) and two-dimensional organic and inorganic hybrid lead halide perovskites (2DPVSKs) have emerged as highly promising materials for ultralight and ultrathin optoelectronics application. They both exhibit tunability of electronic properties such as band structure, and they can form heterostructures with various types of two-dimensional materials for novel physical properties not observed in single components. However, TMDCs exhibit poor emission efficiency due to defect states and direct-to-indirect interband transition, and 2DPVSKs suffer from poor stability in ambient atmosphere. Here we report that fabrication of TMDC-on-2DPVSK heterostructures using a solvent-free process leads to novel optical transitions unique to the heterostructure which arise from the hybrid interface and exhibit a strong photoluminescence. Moreover, a two orders of magnitude enhancement of the photoluminescence as compared to WS_2 emission is observed. The TMDC on top of 2DPVSK also significantly improves the stability as compared to bare 2DPVSK. Enhanced emission can be explained by electronic structure modification of TMDC by novel interfacial interactions between TMDC and 2DPVSK materials, which shows promise of the heterostructure for high efficiency and stable optoelectronic devices.", "date": "2019-08-14", "date_type": "published", "publication": "Nano Letters", "volume": "19", "number": "8", "publisher": "American Chemical Society", "pagerange": "4852-4860", "id_number": "CaltechAUTHORS:20190624-131401605", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190624-131401605", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019140" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FOA-0001647" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-17-1-2231" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.8b05105", "primary_object": { "basename": "nl8b05105_si_001.pdf", "url": "https://authors.library.caltech.edu/records/2ztcn-nwy40/files/nl8b05105_si_001.pdf" }, "pub_year": "2019", "author_list": "Yang, Arky; Blancon, Jean-Christophe; et al." }, { "id": "https://authors.library.caltech.edu/records/m4gqq-g9352", "eprint_id": 95560, "eprint_status": "archive", "datestamp": "2023-08-22 02:08:11", "lastmod": "2023-10-20 20:20:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" }, "orcid": "0000-0002-6155-6825" }, { "id": "Zhong-Lei", "name": { "family": "Zhong", "given": "Lei" } }, { "id": "Mateos-A-J", "name": { "family": "Mateos", "given": "Arturo" } }, { "id": "Kudo-Akira", "name": { "family": "Kudo", "given": "Akira" }, "orcid": "0000-0002-0830-5509" }, { "id": "Vyatskikh-A", "name": { "family": "Vyatskikh", "given": "Andrey" }, "orcid": "0000-0002-6917-6931" }, { "id": "Gao-Huajian", "name": { "family": "Gao", "given": "Huajian" }, "orcid": "0000-0002-8656-846X" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" }, { "id": "Li-Xiaoyan", "name": { "family": "Li", "given": "Xiaoyan" }, "orcid": "0000-0002-2953-9267" } ] }, "title": "Theoretical strength and rubber-like behaviour in micro-sized pyrolytic carbon", "ispublished": "pub", "full_text_status": "public", "keywords": "Mechanical engineering; Nanoscale materials", "note": "\u00a9 2019 Springer Nature Publishing AG. \n\nReceived 11 May 2018; Accepted 24 May 2019; Published 08 July 2019. \n\nData availability: The data that support the plots and other findings of this study are available from the corresponding authors upon request. \n\nX.L. acknowledges financial support from the National Natural Science Foundation of China (grants 11522218 and 11720101002) and the National Basic Research of China (grant 2015CB932500). H.G. acknowledges funding from the National Science Foundation (grant DMR-1709318). J.R.G. acknowledges financial support by the US Department of Energy, Office of Basic Energy Sciences (DOE-BES) under grant DE-SC0006599. A.V. acknowledges the financial support of the Resnick Sustainability Institute at Caltech. The authors thank G. R. Rossman for assistance with Raman spectroscopy measurements, J. Yao for help with SIMS measurements and K. Narita for assistance with density measurements of pyrolytic carbon. \n\nAuthor Contributions: X.Z., X.L., H.G. and J.R.G. conceived and designed the experiments and modelling. X.Z. and A.M. synthesized the experimental samples. X.Z. performed the in situ and ex situ compression experiments. A.M. performed the in situ tension experiments. A.K. and X.Z. performed the HRTEM and EELS analyses. A.V. and L.Z. performed the Raman spectroscopy measurements. L.Z. conducted the atomistic simulations. X.Z., L.Z. and X.L. developed the model. X.Z., L.Z., X.L., H.G. and J.R.G. wrote the manuscript. All authors analysed the data, discussed the results and commented on the manuscript. \n\nThe authors declare no competing interests.\n\n

Supplemental Material - 41565_2019_486_MOESM1_ESM.pdf

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Supplemental Material - 41565_2019_486_MOESM3_ESM.mp4

Supplemental Material - 41565_2019_486_MOESM4_ESM.avi

Supplemental Material - 41565_2019_486_MOESM5_ESM.avi

", "abstract": "The creation of materials with a combination of high strength, substantial deformability and ductility, large elastic limit and low density represents a long-standing challenge, because these properties are, in general, mutually exclusive. Using a combination of two-photon lithography and high-temperature pyrolysis, we have created micro-sized pyrolytic carbon with a tensile strength of 1.60\u2009\u00b1\u20090.55\u2009GPa, a compressive strength approaching the theoretical limit of ~13.7\u2009GPa, a substantial elastic limit of 20\u201330% and a low density of ~1.4\u2009g\u2009cm^(\u22123). This corresponds to a specific compressive strength of 9.79\u2009GPa\u2009cm^3\u2009g^(\u22121), a value that surpasses that of nearly all existing structural materials. Pillars with diameters below 2.3\u2009\u03bcm exhibit rubber-like behaviour and sustain a compressive strain of ~50% without catastrophic failure; larger ones exhibit brittle fracture at a strain of ~20%. Large-scale atomistic simulations reveal that this combination of beneficial mechanical properties is enabled by the local deformation of 1\u2009nm curled graphene fragments within the pyrolytic carbon microstructure, the interactions among neighbouring fragments and the presence of covalent carbon\u2013carbon bonds.", "date": "2019-08", "date_type": "published", "publication": "Nature Nanotechnology", "volume": "14", "number": "8", "publisher": "Nature Publishing Group", "pagerange": "762-769", "id_number": "CaltechAUTHORS:20190517-100134758", "issn": "1748-3387", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190517-100134758", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "11522218" }, { "agency": "National Natural Science Foundation of China", "grant_number": "11720101002" }, { "agency": "National Basic Research of China", "grant_number": "2015CB932500" }, { "agency": "NSF", "grant_number": "DMR-1709318" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006599" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41565-019-0486-y", "primary_object": { "basename": "41565_2019_486_MOESM4_ESM.avi", "url": "https://authors.library.caltech.edu/records/m4gqq-g9352/files/41565_2019_486_MOESM4_ESM.avi" }, "related_objects": [ { "basename": "41565_2019_486_MOESM5_ESM.avi", "url": "https://authors.library.caltech.edu/records/m4gqq-g9352/files/41565_2019_486_MOESM5_ESM.avi" }, { "basename": "41565_2019_486_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/m4gqq-g9352/files/41565_2019_486_MOESM1_ESM.pdf" }, { "basename": "41565_2019_486_MOESM2_ESM.mp4", "url": "https://authors.library.caltech.edu/records/m4gqq-g9352/files/41565_2019_486_MOESM2_ESM.mp4" }, { "basename": "41565_2019_486_MOESM3_ESM.mp4", "url": "https://authors.library.caltech.edu/records/m4gqq-g9352/files/41565_2019_486_MOESM3_ESM.mp4" } ], "pub_year": "2019", "author_list": "Zhang, Xuan; Zhong, Lei; et al." }, { "id": "https://authors.library.caltech.edu/records/jmxxz-xsm58", "eprint_id": 98287, "eprint_status": "archive", "datestamp": "2023-08-19 17:06:56", "lastmod": "2023-10-18 17:13:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dhandapani-C", "name": { "family": "Dhandapani", "given": "Chandru" } }, { "id": "Rah-K-J", "name": { "family": "Rah", "given": "Kyupaeck Jeff" }, "orcid": "0000-0003-1898-2930" }, { "id": "Blanquart-G", "name": { "family": "Blanquart", "given": "Guillaume" }, "orcid": "0000-0002-5074-9728" } ] }, "title": "Effective forcing for direct numerical simulations of the shear layer of turbulent free shear flows", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Physical Society. \n\nReceived 20 December 2017; published 28 August 2019. \n\nWe gratefully acknowledge financial support from the National Science Foundation. (CBET 1512771) and from the Air Force Office of Scientific Research (FA9550-16-1-0510) under the supervision of Dr. Chiping Li, and a graduate fellowship (C.D.) from the Resnick Sustainibility Institute at Caltech.\n\n

Published - PhysRevFluids.4.084606.pdf

", "abstract": "A numerically efficient configuration to simulate turbulent flows is to use triply periodic domains, with numerical forcing techniques to sustain turbulence. Previous homogeneous shear turbulence simulations considered only idealized homogeneous shear flows and not the statistically stationary shear turbulence observed in practical free shear flows. In contrast, the current study mathematically derives the complete forcing technique from the large scales of the turbulent free shear flows. Different statistically stationary free shear flows are considered in this study, namely, a nearly homogeneous shear turbulent flow, turbulent mixing layer, a turbulent planar jet, and a turbulent round jet. The simulations are performed on triply periodic, statistically homogeneous cubic domains in the vicinity of the shear layer in the self-similar region. An a priori analysis is performed to calculate the effects of the different forcing terms and to predict the expected turbulence quantities. The forcing technique is then used to perform direct numerical simulations at different Reynolds numbers. Numerical results for the different cases are discussed and compared with results from experiments and other simulations of free shear turbulent flows. Anisotropy is observed both in the components of velocity and vorticity, with stronger Reynolds number dependence in the anisotropy of vorticity. Energy spectra obtained from the present homogeneous shear turbulence agree well with the spectra from temporally evolving shear layers. The results also highlight the effects of the additional forcing terms that were neglected in previous studies and the role of shear convection and the associated splitting errors in the unbounded evolution of previous numerical simulations.", "date": "2019-08", "date_type": "published", "publication": "Physical Review Fluids", "volume": "4", "number": "8", "publisher": "American Physical Society", "pagerange": "Art. No. 084606", "id_number": "CaltechAUTHORS:20190828-092034904", "issn": "2469-990X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190828-092034904", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CBET-1512771" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0510" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevFluids.4.084606", "primary_object": { "basename": "PhysRevFluids.4.084606.pdf", "url": "https://authors.library.caltech.edu/records/jmxxz-xsm58/files/PhysRevFluids.4.084606.pdf" }, "pub_year": "2019", "author_list": "Dhandapani, Chandru; Rah, Kyupaeck Jeff; et al." }, { "id": "https://authors.library.caltech.edu/records/grthg-0pv69", "eprint_id": 97916, "eprint_status": "archive", "datestamp": "2023-08-19 16:53:45", "lastmod": "2023-10-18 16:52:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kudo-Akira", "name": { "family": "Kudo", "given": "Akira" }, "orcid": "0000-0002-0830-5509" }, { "id": "Misseroni-D", "name": { "family": "Misseroni", "given": "Diego" } }, { "id": "Wei-Yuchen", "name": { "family": "Wei", "given": "Yuchen" } }, { "id": "Bosia-F", "name": { "family": "Bosia", "given": "Federico" }, "orcid": "0000-0002-2886-4519" } ] }, "title": "Compressive Response of Non-slender Octet Carbon Microlattices", "ispublished": "pub", "full_text_status": "public", "keywords": "architected materials, additive manufacturing, structural metamaterials, pyrolyzed lattices, mechanics", "note": "\u00a9 2019 Kudo, Misseroni, Wei and Bosi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. \n\nReceived: 14 January 2019; Accepted: 01 July 2019; Published: 31 July 2019. \n\nAuthor Contributions: AK, DM, and FB designed the research, discussed the results, and wrote the paper. DM and FB carried out the analytical and numerical analyses. AK manufactured the specimens. AK and YW performed the experiments. All authors reviewed the paper and gave final approval for publication. \n\nFunding: Vannevar-Bush Faculty Fellowship of the US Department of Defense. The Resnick Sustainability Institute Postdoctoral Fellowship of Caltech. Financial support from National Group of Mathematical Physics (GNFM-INdAM).\n\nConflict of Interest Statement:\nThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.\n\nAcknowledgments:\nAK gratefully acknowledges the financial support from the Resnick Sustainability Institute at the California Institute of Technology and from Prof. Julia R. Greer (Caltech) through the Vannevar-Bush Faculty Fellowship of the US Department of Defense. The authors thank Prof. Julia R. Greer's research group (Caltech) and Prof. Sergio Pellegrino (Caltech) for their support in conducting experiments in their laboratories.\n\n

Published - fmats-06-00169.pdf

", "abstract": "Lattices are periodic three-dimensional architected solids designed at the micro and nano-scale to achieve unique properties not attainable by their constituent materials. The design of lightweight and strong structured solids by additive manufacturing requires the use of high-strength constituent materials and non-slender geometries to prevent strut elastic instabilities. Low slenderness carbon octet microlattices are obtained through pyrolysis of polymeric architectures manufactured with stereolithography technique. Their compressive behavior is numerically and experimentally investigated when the relative density \u03c1 ranges between 10 and 50%, with specific stiffness and strength approaching the limit of existing micro and nanoarchitectures. It is shown that additive manufacturing can introduce imperfections such as increased nodal volume, non-cubic unit cell, and orientation-dependent beam slenderness, all of which deeply affect the mechanical response of the lattice material. An accurate numerical modeling of non-slender octet lattices with significant nodal volumes is demonstrated to overcome the limitations of classical analytical methods based on beam theory for the prediction of the lattice stiffness, strength and scaling laws. The presented numerical results and experimental methods provide new insights for the design of structural carbon architected materials toward ultra-strong and lightweight solids.", "date": "2019-07-31", "date_type": "published", "publication": "Frontiers in Materials", "volume": "6", "publisher": "Frontiers Media SA", "pagerange": "Art. No. 169", "id_number": "CaltechAUTHORS:20190815-100030629", "issn": "2296-8016", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190815-100030629", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Vannever Bush Faculty Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gruppo Nazionale per la Fisica Matematica" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3389/fmats.2019.00169", "primary_object": { "basename": "fmats-06-00169.pdf", "url": "https://authors.library.caltech.edu/records/grthg-0pv69/files/fmats-06-00169.pdf" }, "pub_year": "2019", "author_list": "Kudo, Akira; Misseroni, Diego; et al." }, { "id": "https://authors.library.caltech.edu/records/40xst-0ex24", "eprint_id": 97168, "eprint_status": "archive", "datestamp": "2023-08-22 02:05:57", "lastmod": "2023-10-20 22:01:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Zeng-Zhao\u2010Cheng", "name": { "family": "Zeng", "given": "Zhao\u2010Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas" }, "orcid": "0000-0001-9465-0853" }, { "id": "Wong-Clare-K", "name": { "family": "Wong", "given": "Clare" } }, { "id": "Liang-Jianming", "name": { "family": "Liang", "given": "Jianming" }, "orcid": "0000-0002-4043-6816" }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Yadav-V", "name": { "family": "Yadav", "given": "Vineet" }, "orcid": "0000-0002-2805-3345" }, { "id": "Verhulst-K-R", "name": { "family": "Verhulst", "given": "Kristal" }, "orcid": "0000-0001-5678-9678" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Duren-R", "name": { "family": "Duren", "given": "Riley" }, "orcid": "0000-0003-4723-5280" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" }, { "id": "Shia-Run\u2010Lie", "name": { "family": "Shia", "given": "Run\u2010Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Atmospheric methane emissions correlate with natural gas consumption from residential and commercial sectors in Los Angeles", "ispublished": "pub", "full_text_status": "public", "keywords": "methane emissions; greenhouse gas; urban pollution; natural gas leakage", "note": "\u00a9 2019 American Geophysical Union. \n\nReceived 19 APR 2019; Accepted 10 JUL 2019; Accepted article online 15 JUL 2019. \n\nThis research was supported by NIST, CARB, and NASA. We gratefully acknowledge discussions with M. Fischer, G. Heath, J. Hedelius, M. Weitz, and V. Camobreco. L.H. thanks the Resnick Sustainability Institute at Caltech for fellowship support. We thank A. Andrews and E. Dlugokencky for providing the NOAA flask measurements at Mt. Wilson Observatory (National Oceanic and Atmospheric Administration, 2019). CLARS\u2010FTS data are available from the NASA Megacities Project (https://megacities.jpl.nasa.gov). The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. L. H., Z. C. Z., T. P., C. W., and S. S. carried out the data acquisition and analysis, J. L. and K. G. provided the Hestia inventory, S. S., L. H., and Z. C. Z. wrote the paper, and all authors contributed to the analysis and discussion of the results. The authors declare no competing financial interests.\n\n

Published - He_et_al-2019-Geophysical_Research_Letters.pdf

Supplemental Material - grl59321-sup-0001-2019gl083400-s01.docx

", "abstract": "Legislation in the State of California mandates reductions in emissions of short\u2010lived climate pollutants of 40% from 2013 levels by 2030 for CH_4. Identification of the sector(s) responsible for these emissions and their temporal and spatial variability is a key step in achieving these goals. Here, we determine the emissions of CH_4 in Los Angeles from 2011\u20132017 using a mountaintop remote sensing mapping spectrometer. We show that the pattern of CH_4 emissions contains both seasonal and nonseasonal contributions. We find that the seasonal component peaks in the winter and is correlated (R^2 = 0.58) with utility natural gas consumption from the residential and commercial sectors and not from the industrial and gas\u2010fired power plant sectors. The nonseasonal component is (22.9 \u00b1 1.4) Gg CH_4/month. If the seasonal correlation is causal, about (1.4 \u00b1 0.1)% of the commercial and residential natural gas consumption in Los Angeles is released into the atmosphere.", "date": "2019-07-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "46", "number": "14", "publisher": "American Geophysical Union", "pagerange": "8563-8571", "id_number": "CaltechAUTHORS:20190716-102712163", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190716-102712163", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "California Air Resources Board" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019gl083400", "primary_object": { "basename": "He_et_al-2019-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/40xst-0ex24/files/He_et_al-2019-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl59321-sup-0001-2019gl083400-s01.docx", "url": "https://authors.library.caltech.edu/records/40xst-0ex24/files/grl59321-sup-0001-2019gl083400-s01.docx" } ], "pub_year": "2019", "author_list": "He, Liyin; Zeng, Zhao\u2010Cheng; et al." }, { "id": "https://authors.library.caltech.edu/records/3aqc2-b0947", "eprint_id": 97554, "eprint_status": "archive", "datestamp": "2023-08-19 16:33:39", "lastmod": "2023-10-18 16:04:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toedtli-S-S", "name": { "family": "Toedtli", "given": "Simon S." } }, { "id": "Luhar-M", "name": { "family": "Luhar", "given": "Mitul" } }, { "id": "McKeon-B-J", "name": { "family": "McKeon", "given": "Beverley J." }, "orcid": "0000-0003-4220-1583" } ] }, "title": "Predicting the response of turbulent channel flow to varying-phase opposition control: Resolvent analysis as a tool for flow control design", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Physical Society. \n\nReceived 3 November 2018; published 31 July 2019. \n\nThe authors gratefully acknowledge the U.S. Air Force Office of Scientific Research (Grant No. FA 9550-16-1-0361) for financial support of this work and a graduate fellowship (S.S.T.) from the Resnick Sustainability Institute at Caltech. We would also like to thank J. Jim\u00e9nez for making his channel DNS code available, P. Koumoutsakos for providing the computational resources for this\nstudy, and the reviewers for their feedback, which has greatly improved the quality of this paper.\n\n

Published - PhysRevFluids.4.073905.pdf

", "abstract": "The present study evaluates the capabilities of a low-order flow model based on the resolvent analysis of McKeon and Sharma [B. J. McKeon and A. S. Sharma, J. Fluid Mech. 658, 336 (2010)] for the purpose of controller design for drag reduction in wall-bounded turbulent flows. To this end, we first show that the model is able to approximate the change in mean wall shear stress, which is commonly used as measure for drag reduction. We also derive an analytical expression that decomposes the drag reduction in internal flows into terms that can be predicted directly by the model and terms that allow for quantification of model error if high-fidelity data are available. We then show by example of varying-phase opposition control in a low-Reynolds-number turbulent channel flow that the drag reduction predicted by the resolvent model captures the trend observed in direct numerical simulation (DNS) over a wide range of controller parameters. The DNS results confirm the resolvent model prediction that the attainable drag reduction strongly depends on the relative phase between sensor measurement and actuator response, which raises interesting flow physics questions for future studies. The good agreement between the resolvent model and DNS further reveals that resolvent analysis, which at its heart is a linear technique, is able to approximate the response of the full nonlinear system to control. We also show that in order to make accurate predictions the model only needs to resolve a small subset of the DNS wave numbers and that the controlled resolvent modes obey the Reynolds-number scaling laws of the uncontrolled resolvent operator derived by Moarref et al. [R. Moarref et al., J. Fluid Mech. 734, 275 (2013)]. As a consequence, our results suggest that resolvent analysis can provide a suitable flow model to design feedback flow control schemes for the purpose of drag reduction in incompressible wall-bounded turbulent flows even at technologically relevant Reynolds numbers.", "date": "2019-07", "date_type": "published", "publication": "Physical Review Fluids", "volume": "4", "number": "7", "publisher": "American Physical Society", "pagerange": "Art. No. 073905", "id_number": "CaltechAUTHORS:20190731-130426261", "issn": "2469-990X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190731-130426261", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA 9550-16-1-0361" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "GALCIT" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevFluids.4.073905", "primary_object": { "basename": "PhysRevFluids.4.073905.pdf", "url": "https://authors.library.caltech.edu/records/3aqc2-b0947/files/PhysRevFluids.4.073905.pdf" }, "pub_year": "2019", "author_list": "Toedtli, Simon S.; Luhar, Mitul; et al." }, { "id": "https://authors.library.caltech.edu/records/zbsxs-54t29", "eprint_id": 95500, "eprint_status": "archive", "datestamp": "2023-08-19 16:20:44", "lastmod": "2023-10-20 20:17:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Reed-C-J", "name": { "family": "Reed", "given": "Christopher J." }, "orcid": "0000-0002-8774-5106" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "A Terminal Fe^(III)-Oxo in a Tetranuclear Cluster: Effects of Distal Metal Centers on Structure and Reactivity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: March 22, 2019; Published: May 14, 2019. \n\nThis research was supported by the NIH (R01-GM102687B) and the Dreyfus Teacher-Scholar Program (T.A.). C.J.R. thanks the Resnick Sustainability Institute at Caltech for a fellowship. We thank Dr. Mike Takase and Larry Henling for assistance with crystallography, Prof. Jonas Peters for use of his group's M\u00f6ssbauer spectrometer, and the Dow Next Generation Educator Fund for instrumentation. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1583112.pdf

Supplemental Material - ja9b03157_si_001.cif

Supplemental Material - ja9b03157_si_002.pdf

", "abstract": "Tetranuclear Fe clusters have been synthesized bearing a terminal Fe^(III)\u2013oxo center stabilized by hydrogen-bonding interactions from pendant (tert-butylamino)pyrazolate ligands. This motif was supported in multiple Fe oxidation states, ranging from [Fe^(II)_2Fe^(III)_2] to [Fe^(III)_4]; two oxidation states were structurally characterized by single-crystal X-ray diffraction. The reactivity of the Fe^(III)\u2013oxo center in proton-coupled electron transfer with X\u2013H (X = C, O) bonds of various strengths was studied in conjunction with analysis of thermodynamic square schemes of the cluster oxidation states. These results demonstrate the important role of distal metal centers in modulating the reactivity of a terminal metal\u2013oxo.", "date": "2019-06-19", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "24", "publisher": "American Chemical Society", "pagerange": "9479-9484", "id_number": "CaltechAUTHORS:20190515-081947535", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190515-081947535", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01-GM102687B" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.9b03157", "pmcid": "PMC7207158", "primary_object": { "basename": "ja9b03157_si_001.cif", "url": "https://authors.library.caltech.edu/records/zbsxs-54t29/files/ja9b03157_si_001.cif" }, "related_objects": [ { "basename": "ja9b03157_si_002.pdf", "url": "https://authors.library.caltech.edu/records/zbsxs-54t29/files/ja9b03157_si_002.pdf" }, { "basename": "nihms-1583112.pdf", "url": "https://authors.library.caltech.edu/records/zbsxs-54t29/files/nihms-1583112.pdf" } ], "pub_year": "2019", "author_list": "Reed, Christopher J. and Agapie, Theodor" }, { "id": "https://authors.library.caltech.edu/records/00ryt-ntc22", "eprint_id": 95955, "eprint_status": "archive", "datestamp": "2023-08-22 01:50:07", "lastmod": "2025-04-23 19:07:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thomas-Nathan-H", "name": { "family": "Thomas", "given": "Nathan H." }, "orcid": "0000-0003-4648-5325" }, { "id": "Sherrott-M-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Brouillet-J-J", "name": { "family": "Brouillet", "given": "Jeremy" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Electronic Modulation of Near-Field Radiative Transfer in Graphene Field Effect Heterostructures", "ispublished": "pub", "full_text_status": "public", "keywords": "Near-field radiative transfer; graphene; electronic modulation; thermal switches", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: March 15, 2019; Revised: May 10, 2019; Published: May 29, 2019. \n\nThis work is part of the Light-Material Interactions in Energy Conversion Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DE-SC0001293. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1144469. M.C.S. gratefully acknowledges fellowship support from the Resnick Sustainability Institute. The authors recognize the Kavli NanoScience Institute at Caltech and to thank Dr. Ognjen Ilic for insightful conversation. \n\nAuthor Contributions: N.H.T. and A.J.M. conceived and designed the experiment. N.H.T. fabricated samples and conducted numerical simulations. M.C.S. assisted in design and sample fabrication. J.B. assisted in sample fabrication. N.H.T., H.A.A., and A.J.M. wrote the manuscript. All authors commented and approved the manuscript. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl9b01086_si_001.pdf

", "abstract": "Manipulating heat flow in a controllable and reversible manner is a topic of fundamental and practical interest. Numerous approaches to perform thermal switching have been reported, but they typically suffer from various limitations, for instance requiring mechanical modulation of a submicron gap spacing or only operating in a narrow temperature window. Here, we report the experimental modulation of radiative heat flow by electronic gating of a graphene field effect heterostructure without any moving elements. We measure a maximum heat flux modulation of 4 \u00b1 3% and an absolute modulation depth of 24 \u00b1 7 mW m^(\u20132) V^(\u20131) in samples with vacuum gap distances ranging from 1 to 3 \u03bcm. The active area in the samples through which heat is transferred is \u223c1 cm^2, indicating the scalable nature of these structures. A clear experimental path exists to realize switching ratios as large as 100%, laying the foundation for electronic control of near-field thermal radiation using 2D materials.", "date": "2019-06-12", "date_type": "published", "publication": "Nano Letters", "volume": "19", "number": "6", "publisher": "American Chemical Society", "pagerange": "3898-3904", "id_number": "CaltechAUTHORS:20190530-095539038", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190530-095539038", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.9b01086", "primary_object": { "basename": "nl9b01086_si_001.pdf", "url": "https://authors.library.caltech.edu/records/00ryt-ntc22/files/nl9b01086_si_001.pdf" }, "pub_year": "2019", "author_list": "Thomas, Nathan H.; Sherrott, Michelle C.; et al." }, { "id": "https://authors.library.caltech.edu/records/3e18j-fhj88", "eprint_id": 95383, "eprint_status": "archive", "datestamp": "2023-08-19 16:12:59", "lastmod": "2023-10-20 20:11:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brandenberg-O-F", "name": { "family": "Brandenberg", "given": "Oliver F." }, "orcid": "0000-0001-5662-1234" }, { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Directed Evolution of a Cytochrome P450 Carbene Transferase for Selective Functionalization of Cyclic Compounds", "ispublished": "pub", "full_text_status": "public", "keywords": "Biocatalysis, Cytochrome P450, Carbene Transfer, Indole Alkylation, Cyclopropanation", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: March 17, 2019; Published: May 9, 2019. \n\nThis work was supported by a grant from the National Science Foundation, Division of Molecular and Cellular Biosciences, to F.H.A. (NSF MCB-1513007). O.F.B. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG grant BR 5238/1-1) and the Swiss National Science Foundation (SNF grant P300PA-171225). K.C. thanks the Resnick Sustainability Institute at Caltech for fellowship support. The authors are grateful to Dr. Christopher Prier for help with initial experimental design and comments on the manuscript. We also thank Dr. David Romney and Anders Knight for helpful comments and discussions. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja9b02931_si_001.pdf

", "abstract": "Transfers of carbene moieties to heterocycles or cyclic alkenes to obtain C(sp^2)\u2013H alkylation or cyclopropane products are valuable transformations for synthesis of pharmacophores and chemical building blocks. Through their readily tunable active-site geometries, hemoprotein \"carbene transferases\" could provide an alternative to traditional transition metal catalysts by enabling heterocycle functionalizations with high chemo-, regio-, and stereocontrol. However, carbene transferases accepting heterocyclic substrates are scarce; the few enzymes capable of heterocycle or cyclic internal alkene functionalization described to date are characterized by low turnovers or depend on artificially introduced, costly iridium\u2013porphyrin cofactors. We addressed this challenge by evolving a cytochrome P450 for highly efficient carbene transfer to indoles, pyrroles, and cyclic alkenes. We first developed a spectrophotometric high-throughput screening assay based on 1-methylindole C3-alkylation that enabled rapid analysis of thousands of P450 variants and comprehensive directed evolution via random and targeted mutagenesis. This effort yielded a P450 variant with 11 amino acid substitutions and a large deletion of the non-catalytic P450 reductase domain, which chemoselectively C_3-alkylates indoles with up to 470 turnovers per minute and 18\u202f000 total turnovers. We subsequently used this optimized alkylation variant for parallel evolution toward more challenging heterocycle carbene functionalizations, including C_2/C_3 regioselective pyrrole alkylation, enantioselective indole alkylation with ethyl 2-diazopropanoate, and cyclic internal alkene cyclopropanation. The resulting set of efficient biocatalysts showcases the tunability of hemoproteins for highly selective functionalization of cyclic targets and the power of directed evolution to enhance the scope of new-to-nature enzyme catalysts.", "date": "2019-06-05", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "22", "publisher": "American Chemical Society", "pagerange": "8989-8995", "id_number": "CaltechAUTHORS:20190509-152409265", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190509-152409265", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "BR 5238/1-1" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300PA-171225" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.9b02931", "primary_object": { "basename": "ja9b02931_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3e18j-fhj88/files/ja9b02931_si_001.pdf" }, "pub_year": "2019", "author_list": "Brandenberg, Oliver F.; Chen, Kai; et al." }, { "id": "https://authors.library.caltech.edu/records/n3bvq-3eb35", "eprint_id": 94070, "eprint_status": "archive", "datestamp": "2023-08-22 01:46:26", "lastmod": "2023-10-20 17:38:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dong-Sijia-S", "name": { "family": "Dong", "given": "Sijia" }, "orcid": "0000-0002-5811-9333" }, { "id": "Berelson-William-M", "name": { "family": "Berelson", "given": "William M." }, "orcid": "0000-0002-1526-3802" }, { "id": "Rollins-Nick-E", "name": { "family": "Rollins", "given": "Nick E." } }, { "id": "Subhas-Adam-V", "name": { "family": "Subhas", "given": "Adam V." }, "orcid": "0000-0002-7688-6624" }, { "id": "Naviaux-John-D", "name": { "family": "Naviaux", "given": "John D." }, "orcid": "0000-0002-0681-3163" }, { "id": "Celestian-Aaron-J", "name": { "family": "Celestian", "given": "Aaron J." }, "orcid": "0000-0003-0775-6380" }, { "id": "Liu-Xuewu", "name": { "family": "Liu", "given": "Xuewu" } }, { "id": "Turaga-Nitya", "name": { "family": "Turaga", "given": "Nitya" } }, { "id": "Kemnitz-Nathaniel-J", "name": { "family": "Kemnitz", "given": "Nathaniel J." } }, { "id": "Byrne-Robert-H", "name": { "family": "Byrne", "given": "Robert H." }, "orcid": "0000-0003-0726-0131" }, { "id": "Adkins-J-F", "name": { "family": "Adkins", "given": "Jess F." }, "orcid": "0000-0002-3174-5190" } ] }, "title": "Aragonite dissolution kinetics and calcite/aragonite ratios in sinking and suspended particles in the North Pacific", "ispublished": "pub", "full_text_status": "public", "keywords": "aragonite dissolution rate; calcite/aragonite ratio; North Pacific", "note": "\u00a9 2019 Elsevier B.V. \n\nReceived 8 November 2018, Revised 8 March 2019, Accepted 10 March 2019, Available online 22 March 2019. \n\nThis work was supported by NSF Ocean Acidification grants (numbers OCE1220600 and OCE1220302), USC Dornsife Doctoral Fellowship, Elizabeth and Jerol Sonosky Fellowship, the Sea Grant Fellowship, and the Resnick Sustainability Institute Graduate Fellowship. The authors would like to acknowledge editor Derek Vance, reviewer Jack Middelburg and another anonymous reviewer for their invaluable comments of the original manuscript. We thank the captain and crews on Kilo Moana for their assistance at sea. We also acknowledge Christopher Moore, Loraine Martell-Bonet for their help measuring pH and alkalinity during CDisK-IV; Yi Hou for leak-checking the Niskin Incubators by measuring dissolved Si concentrations; Doug Hammond for providing the in situ pumps; Johnny Stutsman and James Rae for their help deploying and recovering in situ pumps; as well as Abby Lunstrum and Huanting Hu for their help picking out swimmers from the sediment trap samples.\n\n

Supplemental Material - 1-s2.0-S0012821X19301645-mmc1.pdf

", "abstract": "The lack of consensus on CaCO\u2083 dissolution rates and calcite to aragonite production and export ratios in the ocean poses a significant barrier for the construction of global carbon budgets. We present here a comparison of aragonite dissolution rates measured in the lab vs. in situ along a transect between Hawaii and Alaska using a \u00b9\u00b3C labeling technique. Our results show a general agreement of aragonite dissolution rates in the lab versus in the field, and demonstrate that aragonite, like calcite, shows a non-linear response of dissolution rate as a function of saturation state (\u03a9). Total carbon fluxes along the N. Pacific transect in August 2017, as determined using sediment traps, account for 11\u223c23 weight % of total mass fluxes in the upper 200 m, with a PIC (particulate inorganic carbon)/POC (particulate organic carbon) mole ratio of 0.2\u223c0.6. A comparison of fluxes at depths of 100 m and 200 m indicates that 30\u223c60% PIC dissolves between these depths with 20\u223c70% attenuation in POC fluxes. The molar ratio of PIC to POC loss is 0.29. The simultaneous loss of PIC and POC in the upper 200 m potentially indicates PIC dissolution driven by organic matter respiration, or metazoan/zooplankton consumption. The calcite/aragonite ratio in trap material is significantly lower in the subtropical gyre than in the subarctic gyre. Aragonite fluxes vary from 0.07 to 0.38 mmol m\u207b\u00b2 day\u207b\u00b9 at 100 m, and 0.06 to 0.24 mmol m\u207b\u00b2 day\u207b\u00b9 at 200 m along the North Pacific transect, with no specific trend over latitude. The identification of suspended PIC mineral phases by Raman spectroscopy shows the presence of aragonite below 3000 m in the subtropical gyre, but none in the subpolar gyre. These multiple lines of evidence suggest that predictions based on a strictly thermodynamic view of aragonite dissolution, combined with measured aragonite fluxes, underestimate observed alkalinity excess and measured PIC attenuation in sinking particles. Our measured aragonite flux combined with our inorganic dissolution rate only account for 9% and 0.2% of the excess alkalinity observed in the North Pacific (Feely et al., 2004), assuming aragonite sinking rates of 1 m day\u207b\u00b9 and 100 m day\u207b\u00b9, respectively. However, respiration-driven dissolution or metazoan/zooplankton consumption, indicated by the simultaneous attenuation of PIC and POC in sediment traps, is able to generate the magnitude of dissolution suggested by observed excess alkalinity.", "date": "2019-06-01", "date_type": "published", "publication": "Earth and Planetary Science Letters", "volume": "515", "publisher": "Elsevier", "pagerange": "1-12", "id_number": "CaltechAUTHORS:20190322-142418170", "issn": "0012-821X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190322-142418170", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "OCE-1220600" }, { "agency": "NSF", "grant_number": "OCE-1220302" }, { "agency": "University of Southern California" }, { "agency": "Elizabeth and Jerol Sonosky Fellowship" }, { "agency": "Sea Grant Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.epsl.2019.03.016", "primary_object": { "basename": "1-s2.0-S0012821X19301645-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/n3bvq-3eb35/files/1-s2.0-S0012821X19301645-mmc1.pdf" }, "pub_year": "2019", "author_list": "Dong, Sijia; Berelson, William M.; et al." }, { "id": "https://authors.library.caltech.edu/records/gd13s-kgq32", "eprint_id": 96026, "eprint_status": "archive", "datestamp": "2023-08-19 16:03:00", "lastmod": "2025-04-25 03:18:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moon-Jaeyun", "name": { "family": "Moon", "given": "Jaeyun" } }, { "id": "Hermann-R-P", "name": { "family": "Hermann", "given": "Rapha\u00ebl P." }, "orcid": "0000-0002-6138-5624" }, { "id": "Manley-M-E", "name": { "family": "Manley", "given": "Michael E." }, "orcid": "0000-0003-4053-9986" }, { "id": "Alatas-A", "name": { "family": "Alatas", "given": "Ahmet" }, "orcid": "0000-0001-6521-856X" }, { "id": "Said-A-H", "name": { "family": "Said", "given": "Ayman H." } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Thermal acoustic excitations with atomic-scale wavelengths in amorphous silicon", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Physical Society. \n\nReceived 4 February 2019; revised manuscript received 6 May 2019; published 3 June 2019. \n\nThe authors thank Nathan Sangkook Lee for helpful discussions in sample preparations, Dr. J\u00f6rg Neuefeind and Michelle Everett for assistance in data collection at NOMAD, and Dr. Bianca Haberl for helpful discussions. The authors thank Dr. John Budai for assistance in data collection at HERIX-30. This work was supported by a Samsung Scholarship and a Resnick Fellowship from the Resnick Sustainability Institute at Caltech, and the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. A portion of this research used resources at the Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. \n\nThis paper has been co-authored by employees of UT-Battelle, LLC, under Contract No. DE AC0500OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this paper, or allow others to do so, for the United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan. \n\nJ.M. and A.J.M. conceived the project. J.M. synthesized the a-Si samples. J.M., A.A., A.H.S, R.P.H., and M.E.M conducted the IXS experiments and analyzed the results. R.P.H. performed the RDF measurements. J.M. performed molecular dynamics calculations. J.M. and A.J.M. wrote the paper with input from all authors. A.J.M. supervised the project. \n\nThe authors declare no competing interests.\n\n

Published - PhysRevMaterials.3.065601.pdf

Supplemental Material - Supplementaryt.pdf

", "abstract": "The vibrational properties of glasses remain a topic of intense interest due to several unresolved puzzles, including the origin of the Boson peak and the mechanisms of thermal transport. Inelastic scattering measurements have revealed that amorphous solids support collective acoustic excitations with low THz frequencies despite the atomic disorder, but these frequencies are well below most of the thermal vibrational spectrum. Here, we report the observation of acoustic excitations with frequencies up to 10 THz in amorphous silicon. The excitations have atomic-scale wavelengths as short as 6 \u00c5 and exist well into the thermal vibrational frequencies. Simulations indicate that these high-frequency waves are supported due to the high group velocity and monatomic composition of a-Si, suggesting that other glasses with these characteristics may also exhibit such excitations. Our findings demonstrate that a substantial portion of thermal vibrational modes in amorphous materials can still be described as a phonon gas despite the lack of atomic order.", "date": "2019-06", "date_type": "published", "publication": "Physical Review Materials", "volume": "3", "number": "6", "publisher": "American Physical Society (APS)", "pagerange": "Art. No. 065601", "id_number": "CaltechAUTHORS:20190603-091248429", "issn": "2475-9953", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190603-091248429", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Samsung Scholarship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevmaterials.3.065601", "primary_object": { "basename": "PhysRevMaterials.3.065601.pdf", "url": "https://authors.library.caltech.edu/records/gd13s-kgq32/files/PhysRevMaterials.3.065601.pdf" }, "related_objects": [ { "basename": "Supplementaryt.pdf", "url": "https://authors.library.caltech.edu/records/gd13s-kgq32/files/Supplementaryt.pdf" } ], "pub_year": "2019", "author_list": "Moon, Jaeyun; Hermann, Rapha\u00ebl P.; et al." }, { "id": "https://authors.library.caltech.edu/records/j5bpp-2ek09", "eprint_id": 93857, "eprint_status": "archive", "datestamp": "2023-08-19 15:57:23", "lastmod": "2023-10-20 17:28:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Martinolich-A-J", "name": { "family": "Martinolich", "given": "Andrew J." }, "orcid": "0000-0002-7866-9594" }, { "id": "Lee-Cheng-Wei", "name": { "family": "Lee", "given": "Cheng-Wei" } }, { "id": "Lu-I-Te", "name": { "family": "Lu", "given": "I-Te" } }, { "id": "Bevilacqua-S-C", "name": { "family": "Bevilacqua", "given": "Sarah C." }, "orcid": "0000-0002-6834-7145" }, { "id": "Preefer-M-B", "name": { "family": "Preefer", "given": "Molleigh B." }, "orcid": "0000-0002-3699-8613" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" }, { "id": "Schleife-A", "name": { "family": "Schleife", "given": "Andr\u00e9" }, "orcid": "0000-0003-0496-8214" }, { "id": "See-Kimberly-A", "name": { "family": "See", "given": "Kimberly A." }, "orcid": "0000-0002-0133-9693" } ] }, "title": "Solid-State Divalent Ion Conduction in ZnPS_3", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: January 16, 2019; Revised: February 28, 2019; Publication Date (Web): March 15, 2019. \n\nFinancial support from Caltech and the Dow Next Generation Educator Fund is gratefully acknowledged. A.J.M. acknowledges postdoctoral fellowship from the Resnick Sustainability Institute at Caltech. M.B.P. acknowledges support from the Mellichamp Sustainability Fellowship at UCSB. Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. I.-T.L. was supported by the Air Force Office of Scientific Research through the Young Investigator Program Grant FA9550-18-1-0280. A.S. acknowledges support from the National Science Foundation under Grant No. DMR-1555153. This work made use of the Illinois Campus Cluster, a computing resource operated by the Illinois Campus Cluster Program (ICCP) in conjunction with the National Center for Supercomputing Applications (NCSA) supported by funds from the University of Illinois at Urbana-Champaign. This research is part of the Blue Waters sustained-petascale computing project, which is supported by the National Science Foundation (awards OCI-0725070 and ACI-1238993) and the state of Illinois. Blue Waters is a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE- AC02-05CH11231. The authors thank Dr. Chi Ma for assistance in the collection of SEM images and Dr. Sonjong Hwang for assistance in the collection of NMR spectra. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cm9b00207_si_001.pdf

", "abstract": "Next-generation batteries based on divalent working ions have the potential to both reduce the cost of energy storage devices and increase performance. Examples of promising divalent systems include those based on Mg^(2+), Ca^(2+), and Zn^(2+) working ions. Development of such technologies is slow, however, in part due to the difficulty associated with divalent cation conduction in the solid state. Divalent ion conduction is especially challenging in insulating materials that would be useful as solid-state electrolytes or protecting layers on the surfaces of metal anodes. Furthermore, there are no reports of divalent cation conduction in insulating, inorganic materials at reasonable temperatures, prohibiting the development of structure\u2013property relationships. Here, we report Zn^(2+) conduction in insulating ZnPS_3, demonstrating divalent ionic conductivity in an ordered, inorganic lattice near room temperature. Importantly, the activation energy associated with the bulk conductivity is low, 351 \u00b1 99 meV, comparable to some Li+conductors such as LTTO, although not as low as the superionic Li+ conductors. First-principles calculations suggest that the barrier corresponds to vacancy-mediated diffusion. Assessment of the structural distortions observed along the ion diffusion pathways suggests that an increase in the P\u2013P\u2013S bond angle in the [P_2S_6]^(4\u2013) moiety accommodates the Zn^(2+) as it passes through the high-energy intermediate coordination environments. ZnPS_3 now represents a baseline material family to begin developing the structure\u2013property relationships that control divalent ion diffusion and conduction in insulating solid-state hosts.", "date": "2019-05-28", "date_type": "published", "publication": "Chemistry of Materials", "volume": "31", "number": "10", "publisher": "American Chemical Society", "pagerange": "3652-3661", "id_number": "CaltechAUTHORS:20190315-083524097", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190315-083524097", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of California, Santa Barbara" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "NSF", "grant_number": "DMR-1555153" }, { "agency": "University of Illinois Urbana-Champaign" }, { "agency": "NSF", "grant_number": "OCI-0725070" }, { "agency": "NSF", "grant_number": "ACI-1238993" }, { "agency": "State of Illinois" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemmater.9b00207", "primary_object": { "basename": "cm9b00207_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j5bpp-2ek09/files/cm9b00207_si_001.pdf" }, "pub_year": "2019", "author_list": "Martinolich, Andrew J.; Lee, Cheng-Wei; et al." }, { "id": "https://authors.library.caltech.edu/records/8yfb7-v6n21", "eprint_id": 94688, "eprint_status": "archive", "datestamp": "2023-08-19 15:55:17", "lastmod": "2023-10-20 18:10:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Sebastian-J-R", "name": { "family": "Lee", "given": "Sebastian J. R." }, "orcid": "0000-0001-7006-9378" }, { "id": "Welborn-M-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Projection-Based Wavefunction-in-DFT Embedding", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: December 31, 2018; Published: April 10, 2019. \n\nS.J.R.L. and M.W. thank the Resnick Sustainability Institute for graduate student and postdoctoral fellowships, respectively. T.F.M. acknowledges support in part from the NSF (Award CHE-1611581). F.R.M. acknowledges support in part from the EPSRC (Grant EP/M013111/1). T.F.M. and F.R.M. also thank the DOE for support (Award DE-FOA-0001912).", "abstract": "Complex chemical systems present challenges to electronic structure theory stemming from large system sizes, subtle interactions, coupled dynamical time scales, and electronically nonadiabatic effects. New methods are needed to perform reliable, rigorous, and affordable electronic structure calculations for simulating the properties and dynamics of such systems. \n\nThis Account reviews projection-based quantum embedding for electronic structure, which provides a formally exact method for density functional theory (DFT) embedding. The method also provides a rigorous and accurate approach for describing a small part of a chemical system at the level of a correlated wavefunction (WF) method while the remainder of the system is described at the level of DFT. A key advantage of projection-based embedding is that it can be formulated in terms of an extremely simple level-shift projection operator, which eliminates the need for any optimized effective potential calculation or kinetic energy functional approximation while simultaneously ensuring that no extra programming is needed to perform WF-in-DFT embedding with an arbitrary WF method. The current work presents the theoretical underpinnings of projection-based embedding, describes use of the method for combining wavefunction and density functional theories, and discusses technical refinements that have improved the applicability and robustness of the method. \n\nApplications of projection-based WF-in-DFT embedding are also reviewed, with particular focus on recent work on transition-metal catalysis, enzyme reactivity, and battery electrolyte decomposition. In particular, we review the application of projection-based embedding for the prediction of electrochemical potentials and reaction pathways in a Co-centered hydrogen evolution catalyst. Projection-based WF-in-DFT calculations are shown to provide quantitative accuracy while greatly reducing the computational cost compared with a reference coupled cluster calculation on the full system. Additionally, projection-based WF-in-DFT embedding is used to study the mechanism of citrate synthase; it is shown that projection-based WF-in-DFT largely eliminates the sensitivity of the potential energy landscape to the employed DFT exchange\u2013correlation functional. Finally, we demonstrate the use of projection-based WF-in-DFT to study electron transfer reactions associated with battery electrolyte decomposition. Projection-based WF-in-DFT embedding is used to calculate the oxidation potentials of neat ethylene carbonate (EC), neat dimethyl carbonate (DMC), and 1:1 mixtures of EC and DMC in order to overcome qualitative inaccuracies in the electron densities and ionization energies obtained from conventional DFT methods. By further embedding the WF-in-DFT description in a molecular mechanics point-charge environment, this work enables an explicit description of the solvent and ensemble averaging of the solvent configurations. \n\nLooking forward, we anticipate continued refinement of the projection-based embedding methodology as well as its increasingly widespread application in diverse areas of chemistry, biology, and materials science.", "date": "2019-05-21", "date_type": "published", "publication": "Accounts of Chemical Research", "volume": "52", "number": "5", "publisher": "American Chemical Society", "pagerange": "1359-1368", "id_number": "CaltechAUTHORS:20190412-101432323", "issn": "0001-4842", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190412-101432323", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1611581" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FOA-0001912" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.accounts.8b00672", "pub_year": "2019", "author_list": "Lee, Sebastian J. R.; Welborn, Matthew; et al." }, { "id": "https://authors.library.caltech.edu/records/628b7-hhq42", "eprint_id": 94908, "eprint_status": "archive", "datestamp": "2023-08-19 15:46:57", "lastmod": "2023-10-20 18:23:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schild-Dirk-J", "name": { "family": "Schild", "given": "Dirk J." } }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Light Enhanced Fe-Mediated Nitrogen Fixation: Mechanistic Insights Regarding H\u2082 Elimination, HER, and NH\u2083 Generation", "ispublished": "pub", "full_text_status": "public", "keywords": "ammonia synthesis, nitrogen fixation, N2RR, nitrogenase, hydrogen evolution, HER, iron catalysis, photocatalysis", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: February 4, 2019; Revised: March 21, 2019; Published: March 26, 2019. \n\nDr. Michael Takase, Larry Henling, and Dr. Marcus Drover are acknowledged for their assistance with crystallographic studies. Dr. Niklas Thompson is thanked for assisting with fitting the variable temperature NMR data. We are grateful to the NIH (GM-075757) for support of this research, and also to the National Science Foundation for support of the Caltech EPR Facility via the NSF-MRI Grant NSF-153194, and to the Dow Next Generation Educator Fund. D.J.S. acknowledges the support of the Resnick Sustainability Institute at Caltech for a Graduate Fellowship. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1036680.pdf

Supplemental Material - cs9b00523_si_001.pdf

Supplemental Material - cs9b00523_si_002.cif

Supplemental Material - cs9b00523_si_003.mol

", "abstract": "Despite their proposed accumulation at the Fe sites of the FeMo-cofactor of MoFe-nitrogenase, the presence of hydride ligands in molecular model systems capable of the nitrogen reduction reaction (N_2RR) appears to diminish catalytic N\u2082-to-NH\u2083 conversion. We find that, for an iron-based system bearing the trisphosphine ligand P_2P^(Ph), a dramatic difference in yields is observed for N2RR catalyzed by precatalysts with zero, one, or two hydride ligands; however, irradiating the three different catalysts with a mercury lamp results in similar NH\u2083 yields. Although the efficacy for N\u2082RR versus the hydrogen evolution reaction (HER) is modest for this system by comparison to certain iron (and other metal) catalysts, the system provides an opportunity to study the role of hydrides in the selectivity for N\u2082RR versus HER, which is a central issue in catalyst design. Stoichiometric reactions with hydride containing precatalysts reveal a hydrogen evolution cycle in which no nitrogen fixation occurs. Irradiation of the dihydride precatalysts, observed during turnover, results in H2 elimination and formation of (P\u2082P^(Ph))Fe(N\u2082)\u2082, which itself is unreactive with acids at low temperature. N\u2082 functionalization does occur with acids and silyl electrophiles for the reduced species [(P\u2082P^(Ph))Fe(N\u2082]\u207b and [(P\u2082P^(Ph))Fe(N\u2082)]\u00b2\u207b, which have been characterized independently. The requirement of accessing such low formal oxidation states explains the need for strong reductants. The low selectivity of the system for functionalization at N\u03b2 versus Fe creates off-path hydride species that participate in unproductive HER, helping to explain the low selectivity for N\u2082RR over HER. The data presented here thus lend further insight into the growing understanding of the selectivity, activity, and reductant strengths relevant to iron (and other) N\u2082RR catalysts.", "date": "2019-05-03", "date_type": "published", "publication": "ACS Catalysis", "volume": "9", "number": "5", "publisher": "American Chemical Society", "pagerange": "4286-4295", "id_number": "CaltechAUTHORS:20190423-160445593", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190423-160445593", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM-075757" }, { "agency": "NSF", "grant_number": "MRI-153194" }, { "agency": "Dow Next Generation Educator Fund" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscatal.9b00523", "pmcid": "PMC6715299", "primary_object": { "basename": "nihms-1036680.pdf", "url": "https://authors.library.caltech.edu/records/628b7-hhq42/files/nihms-1036680.pdf" }, "related_objects": [ { "basename": "cs9b00523_si_001.pdf", "url": "https://authors.library.caltech.edu/records/628b7-hhq42/files/cs9b00523_si_001.pdf" }, { "basename": "cs9b00523_si_002.cif", "url": "https://authors.library.caltech.edu/records/628b7-hhq42/files/cs9b00523_si_002.cif" }, { "basename": "cs9b00523_si_003.mol", "url": "https://authors.library.caltech.edu/records/628b7-hhq42/files/cs9b00523_si_003.mol" } ], "pub_year": "2019", "author_list": "Schild, Dirk J. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/y7c2k-yxh67", "eprint_id": 94588, "eprint_status": "archive", "datestamp": "2023-08-22 01:26:31", "lastmod": "2023-10-23 16:08:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chadwick-A-J", "name": { "family": "Chadwick", "given": "A. J." }, "orcid": "0000-0002-2552-0083" }, { "id": "Lamb-M-P", "name": { "family": "Lamb", "given": "M. P." }, "orcid": "0000-0002-5701-0504" }, { "id": "Moodie-A-J", "name": { "family": "Moodie", "given": "A. J." }, "orcid": "0000-0002-6745-036X" }, { "id": "Parker-G", "name": { "family": "Parker", "given": "G." }, "orcid": "0000-0001-5973-5296" }, { "id": "Nittrouer-J-A", "name": { "family": "Nittrouer", "given": "J. A." }, "orcid": "0000-0002-4762-0157" } ] }, "title": "Origin of a preferential avulsion node on lowland river deltas", "ispublished": "pub", "full_text_status": "public", "keywords": "river avulsion; avulsion node; delta apex; lowland deltas; flood variability; backwater", "note": "\u00a9 2019 American Geophysical Union. \n\nReceived 17 FEB 2019; Accepted 31 MAR 2019; Accepted article online 4 APR 2019; Published online 25 APR 2019. \n\nWe acknowledge National Science Foundation grant EAR 1427262 and the Resnick Sustainability Institute at Caltech for support. We thank Vamsi Ganti, Gail Kineke, Ben Hobbs, Hongbo Ma, Brandee Carlson, Kensuke Naito, and Lisa Kumpf for insightful discussions, and Elizabeth Hajek and Wonsuck Kim for constructive reviews. \n\nData are available at: http://sead-published.ncsa.illinois.edu/seadrepository/api/researchobjects/urn:uuid:5c37c889e4b0a8e144f6565f \n\nCode is available at: https://github.com/achadwick2323/Origin-of-a-preferential-avulsion-node-on-lowland-river-deltas\n\n

Published - Chadwick_et_al-2019-Geophysical_Research_Letters.pdf

Supplemental Material - grl58837-sup-0001-2019gl082491-si.pdf

", "abstract": "River deltas are built by cycles of lobe growth and abrupt channel shifts, or avulsions, that occur within the backwater zone of coastal rivers. Previous numerical models differ on the origin of backwater\u2010scaled avulsion nodes and their consistency with experimental data. To unify previous work, we developed a numerical model of delta growth that includes backwater hydrodynamics, river mouth progradation, relative sea level rise, variable flow regimes, and cycles of lobe growth, abandonment, and reoccupation. For parameter space applicable to lowland deltas, we found that flow variability is the primary mechanism to cause persistent avulsion nodes by focusing aggradation within the backwater zone. Backwater\u2010scaled avulsion nodes also occur under less likely scenarios of initially uniform bed slopes or during rapid relative sea level rise and marine transgression. Our findings suggest that flow variability is a fundamental control on long\u2010term delta morphodynamics.", "date": "2019-04-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "46", "number": "8", "publisher": "American Geophysical Union", "pagerange": "4267-4277", "id_number": "CaltechAUTHORS:20190409-112905807", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190409-112905807", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EAR-1427262" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019gl082491", "primary_object": { "basename": "Chadwick_et_al-2019-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/y7c2k-yxh67/files/Chadwick_et_al-2019-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl58837-sup-0001-2019gl082491-si.pdf", "url": "https://authors.library.caltech.edu/records/y7c2k-yxh67/files/grl58837-sup-0001-2019gl082491-si.pdf" } ], "pub_year": "2019", "author_list": "Chadwick, A. J.; Lamb, M. P.; et al." }, { "id": "https://authors.library.caltech.edu/records/r1h22-rqy17", "eprint_id": 94699, "eprint_status": "archive", "datestamp": "2023-08-19 15:21:13", "lastmod": "2023-10-20 18:11:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Lixue", "name": { "family": "Cheng", "given": "Lixue" }, "orcid": "0000-0002-7329-0585" }, { "id": "Welborn-M-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Christensen-A-S", "name": { "family": "Christensen", "given": "Anders S." }, "orcid": "0000-0002-7253-6897" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "A universal density matrix functional from molecular orbital-based machine learning: Transferability across organic molecules", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published under license by AIP Publishing. \n\nSubmitted: 10 January 2019; Accepted: 19 March 2019; Published Online: 4 April 2019. \n\nWe thank Daniel Smith (Molecular Sciences Software Institute) and Alberto Gobbi (Genentech) for a helpful discussion about available training datasets. T.F.M. acknowledges support from AFOSR Award No. FA9550-17-1-0102. A.S.C. acknowledges support from the National Centre of Competence in Research (NCCR) Materials Revolution: Computational Design and Discovery of Novel Materials (MARVEL) of the Swiss National Science Foundation (SNSF). We also acknowledge support from the Resnick Sustainability Institute postdoctoral fellowship (M.W.) and the Camille Dreyfus Teacher-Scholar Award (T.F.M.). Computational resources were provided by the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the DOE Office of Science under Contract No. DE-AC02-05CH11231.\n\n

Published - 1.5088393.pdf

Submitted - 1901.03309.pdf

Supplemental Material - supportinginformation.pdf

", "abstract": "We address the degree to which machine learning (ML) can be used to accurately and transferably predict post-Hartree-Fock correlation energies. Refined strategies for feature design and selection are presented, and the molecular-orbital-based machine learning (MOB-ML) method is applied to several test systems. Strikingly, for the second-order M\u00f8ller-Plessett perturbation theory, coupled cluster with singles and doubles (CCSD), and CCSD with perturbative triples levels of theory, it is shown that the thermally accessible (350 K) potential energy surface for a single water molecule can be described to within 1 mhartree using a model that is trained from only a single reference calculation at a randomized geometry. To explore the breadth of chemical diversity that can be described, MOB-ML is also applied to a new dataset of thermalized (350 K) geometries of 7211 organic models with up to seven heavy atoms. In comparison with the previously reported \u0394-ML method, MOB-ML is shown to reach chemical accuracy with threefold fewer training geometries. Finally, a transferability test in which models trained for seven-heavy-atom systems are used to predict energies for thirteen-heavy-atom systems reveals that MOB-ML reaches chemical accuracy with 36-fold fewer training calculations than \u0394-ML (140 vs 5000 training calculations).", "date": "2019-04-07", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "150", "number": "13", "publisher": "American Institute of Physics", "pagerange": "Art. No. 131103", "id_number": "CaltechAUTHORS:20190415-085751643", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190415-085751643", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-17-1-0102" }, { "agency": "Swiss National Science Foundation (SNSF)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.5088393", "primary_object": { "basename": "1.5088393.pdf", "url": "https://authors.library.caltech.edu/records/r1h22-rqy17/files/1.5088393.pdf" }, "related_objects": [ { "basename": "1901.03309.pdf", "url": "https://authors.library.caltech.edu/records/r1h22-rqy17/files/1901.03309.pdf" }, { "basename": "supportinginformation.pdf", "url": "https://authors.library.caltech.edu/records/r1h22-rqy17/files/supportinginformation.pdf" } ], "pub_year": "2019", "author_list": "Cheng, Lixue; Welborn, Matthew; et al." }, { "id": "https://authors.library.caltech.edu/records/fmrqg-18m60", "eprint_id": 92253, "eprint_status": "archive", "datestamp": "2023-08-22 01:14:09", "lastmod": "2023-10-20 00:08:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zocca-A", "name": { "family": "Zocca", "given": "Alessandro" }, "orcid": "0000-0001-6585-4785" } ] }, "title": "Temporal starvation in multi-channel CSMA networks: an analytical framework", "ispublished": "pub", "full_text_status": "public", "keywords": "Random-access networks; Performance evaluation; Throughput analysis; Markov process; Hitting times; Mixing times; Partial q-coloring", "note": "\u00a9 2019 Springer Science+Business Media, LLC, part of Springer Nature. \n\nReceived: 10 November 2018; First Online: 14 January 2019. \n\nThe author acknowledges the NWO Rubicon Grant 680.50.1529 and the Resnick Sustainability Institute at Caltech for the support and is grateful to Sem Borst for the discussions at the early stages of this work.\n\n

Accepted Version - 1808.03602.pdf

", "abstract": "In this paper, we consider a stochastic model for a frequency-agile CSMA protocol for wireless networks where multiple orthogonal frequency channels are available. Even when the possible interference on the different channels is described by different conflict graphs, we show that the network dynamics can be equivalently described as that of a single-channel CSMA algorithm on an appropriate virtual network. Our focus is on the asymptotic regime in which the network nodes try to activate aggressively in order to achieve maximum throughput. Of particular interest is the scenario where the number of available channels is not sufficient for all nodes of the network to be simultaneously active and the well-studied temporal starvation issues of the single-channel CSMA dynamics persist. For most networks, we expect that a larger number of available channels should alleviate these temporal starvation issues. However, we prove that the aggregate throughput is a non-increasing function of the number of available channels. To investigate this trade-off that emerges between aggregate throughput and temporal starvation phenomena, we propose an analytic framework to study the transient dynamics of multi-channel CSMA networks by means of first hitting times. Our analysis further reveals that the mixing time of the activity process does not always correctly characterize the temporal starvation in the multi-channel scenario and often leads to pessimistic performance estimates.", "date": "2019-04", "date_type": "published", "publication": "Queueing Systems", "volume": "91", "number": "3-4", "publisher": "Springer", "pagerange": "241-263", "id_number": "CaltechAUTHORS:20190114-132610158", "issn": "0257-0130", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190114-132610158", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "680.50.1529" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s11134-019-09598-y", "primary_object": { "basename": "1808.03602.pdf", "url": "https://authors.library.caltech.edu/records/fmrqg-18m60/files/1808.03602.pdf" }, "pub_year": "2019", "author_list": "Zocca, Alessandro" }, { "id": "https://authors.library.caltech.edu/records/1z5fp-56z23", "eprint_id": 93165, "eprint_status": "archive", "datestamp": "2023-08-19 14:58:28", "lastmod": "2023-10-20 16:48:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chalkley-M-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Oyala-P-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Cp* Noninnocence Leads to a Remarkably Weak C\u2013H Bond via Metallocene Protonation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: January 7, 2019; Published: February 21, 2019. \n\nThis work was supported by Department of Energy (DOE-0235032). MJC acknowledges support from the Center for Environmental Microbial Interactions (CEMI) and the Resnick Sustainability Institute at Caltech. The Caltech EPR facility was supported by the National Science Foundation (NSF MRI-153194) and the Dow Next Generation Educator Fund. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja9b00193_si_001.pdf

Supplemental Material - ja9b00193_si_002.cif

Supplemental Material - ja9b00193_si_003.mol

", "abstract": "Metallocenes, including their permethylated variants, are extremely important in organometallic chemistry. In particular, many are synthetically useful either as oxidants (e.g., Cp_2Fe^+) or as reductants (e.g., Cp_2Co, Cp*_2Co, and Cp*_2Cr). The latter have proven to be useful reagents in the reductive protonation of small-molecule substrates, including N_2. As such, understanding the behavior of these metallocenes in the presence of acids is paramount. In the present study, we undertake the rigorous characterization of the protonation products of Cp*_2Co using pulse electron paramagnetic resonance (EPR) techniques at low temperature. We provide unequivocal evidence for the formation of the ring-protonated isomers Cp*(exo/endo-\u03b7^4-C_5Me_5H)Co^+. Variable temperature Q-band (34 GHz) pulse EPR spectroscopy, in conjunction with density functional theory (DFT) predictions, are key to reliably assigning the Cp*(exo/endo-\u03b7^4-C_5Me_5H)Co^+ species. We also demonstrate that exo-protonation selectivity can be favored by using a bulkier acid and suggest this species is thus likely a relevant intermediate during catalytic nitrogen fixation given the bulky anilinium acids employed. Of further interest, we provide physical data to experimentally assess the C\u2013H bond dissociation free energy (BDFE_(C\u2013H)) for Cp*(exo-\u03b7^4-C_5Me_5H)Co^+. These experimental data support our prior DFT predictions of an exceptionally weak C\u2013H bond (<29 kcal mol^(\u20131)), making this system among the most reactive (with respect to C\u2013H bond strength) to be thoroughly characterized. These data also point to the propensity of Cp*(exo-\u03b7^4-C_5Me_5H)Co to mediate hydride (H\u2013) transfer. Our findings are not limited to the present protonated metallocene system. Accordingly, we outline an approach to rationalizing the reactivity of arene-protonated metal species, using decamethylnickelocene as an additional example.", "date": "2019-03-20", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "11", "publisher": "American Chemical Society", "pagerange": "4721-4729", "id_number": "CaltechAUTHORS:20190221-125557747", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190221-125557747", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DOE-0235032" }, { "agency": "Caltech Center for Environmental Microbial Interactions (CEMI)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "MRI-153194" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Caltech-Center-for-Environmental-Microbial-Interactions-(CEMI)" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.9b00193", "primary_object": { "basename": "ja9b00193_si_001.pdf", "url": "https://authors.library.caltech.edu/records/1z5fp-56z23/files/ja9b00193_si_001.pdf" }, "related_objects": [ { "basename": "ja9b00193_si_002.cif", "url": "https://authors.library.caltech.edu/records/1z5fp-56z23/files/ja9b00193_si_002.cif" }, { "basename": "ja9b00193_si_003.mol", "url": "https://authors.library.caltech.edu/records/1z5fp-56z23/files/ja9b00193_si_003.mol" } ], "pub_year": "2019", "author_list": "Chalkley, Matthew J.; Oyala, Paul H.; et al." }, { "id": "https://authors.library.caltech.edu/records/qctsv-50q51", "eprint_id": 94263, "eprint_status": "archive", "datestamp": "2023-08-19 14:55:13", "lastmod": "2023-10-20 17:49:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kong-Ziyun", "name": { "family": "Kong", "given": "Ziyun" } }, { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Sandoval-O-E", "name": { "family": "Sandoval", "given": "Oscar E." } }, { "id": "Liu-Bohao", "name": { "family": "Liu", "given": "Bohao" } }, { "id": "Wang-Cong", "name": { "family": "Wang", "given": "Cong" } }, { "id": "Jaramillo-Villegas-J-A", "name": { "family": "Jaramillo-Villegas", "given": "Jose A." } }, { "id": "Qi-Minghao", "name": { "family": "Qi", "given": "Minghao" } }, { "id": "Weiner-A-M", "name": { "family": "Weiner", "given": "Andrew M." }, "orcid": "0000-0002-1334-8183" } ] }, "title": "Characterizing pump line phase offset of a single-soliton Kerr comb by dual comb interferometry", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 Optical Society of America. \n\nReceived 7 January 2019; revised 12 February 2019; accepted 13 February 2019; posted 14 February 2019 (Doc. ID 356985); published 13 March 2019. \n\nC. Bao gratefully acknowledges a postdoctoral fellowship from the Resnick Institute, Caltech. \n\nFunding: National Science Foundation (NSF) (1509578-ECCS, 1809784-ECCS); Air Force Office of Scientific Research (AFOSR) (FA9550-15-1-0211); Defense Advanced Research Projects Agency (DARPA) (W31P4Q-13-1-0018).", "abstract": "We report phase retrieval of a single-soliton Kerr comb using electric field cross-correlation implemented via dual-comb interferometry. The phase profile of the Kerr comb is acquired through the heterodyne beat between the Kerr comb and an electro-optic comb with a pre-characterized phase profile. The soliton Kerr comb has a nearly flat phase profile, and the pump line is observed to show a phase offset which depends on the pumping parameters. The experimental results are in agreement with numerical simulations.", "date": "2019-03-15", "date_type": "published", "publication": "Optics Letters", "volume": "44", "number": "6", "publisher": "Optical Society of America", "pagerange": "1460-1463", "id_number": "CaltechAUTHORS:20190328-165907668", "issn": "0146-9592", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190328-165907668", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ECCS-1509578" }, { "agency": "NSF", "grant_number": "ECCS-1809784" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-15-1-0211" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W31P4Q-13-1-0018" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1364/ol.44.001460", "pub_year": "2019", "author_list": "Kong, Ziyun; Bao, Chengying; et al." }, { "id": "https://authors.library.caltech.edu/records/dwnx0-jbv96", "eprint_id": 92933, "eprint_status": "archive", "datestamp": "2023-08-19 14:43:36", "lastmod": "2023-10-20 16:39:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thompson-Niklas-B", "name": { "family": "Thompson", "given": "Niklas B." }, "orcid": "0000-0003-2745-4945" }, { "id": "Oyala-Paul-H", "name": { "family": "Oyala", "given": "Paul H." }, "orcid": "0000-0002-8761-4667" }, { "id": "Dong-Hai-T", "name": { "family": "Dong", "given": "Hai T." }, "orcid": "0000-0002-8914-3045" }, { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Zhao-Jiyong", "name": { "family": "Zhao", "given": "Jiyong" }, "orcid": "0000-0002-0777-3626" }, { "id": "Alp-Esen-Ercan", "name": { "family": "Alp", "given": "E. Ercan" }, "orcid": "0000-0002-4803-8863" }, { "id": "Hu-Michael-Y", "name": { "family": "Hu", "given": "Michael" }, "orcid": "0000-0002-3718-7169" }, { "id": "Lehnert-Nicolai", "name": { "family": "Lehnert", "given": "Nicolai" }, "orcid": "0000-0002-5221-5498" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Electronic Structures of an [Fe(NNR_2)]^(+/0/\u2013) Redox Series: Ligand Noninnocence and Implications for Catalytic Nitrogen Fixation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: January 14, 2019; Published: February 14, 2019. \n\nThis work was supported by the Resnick Sustainability Institute at Caltech (a graduate fellowship to N.B.T.), as well as the NIH (Grant GM 070757). The EPR facility at the California Institute of Technology is supported by the NSF via its MRI program (Grant NSF-1531940) and the Dow Next Generation Educator Fund. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1037227.pdf

Supplemental Material - ic9b00133_si_001.pdf

", "abstract": "The intermediacy of metal\u2013NNH_2 complexes has been implicated in the catalytic cycles of several examples of transition-metal-mediated nitrogen (N_2) fixation. In this context, we have shown that triphosphine-supported Fe(N_2) complexes can be reduced and protonated at the distal N atom to yield Fe(NNH_2) complexes over an array of charge and oxidation states. Upon exposure to further H^+/e^\u2013 equivalents, these species either continue down a distal-type Chatt pathway to yield a terminal iron(IV) nitride or instead follow a distal-to-alternating pathway resulting in N\u2013H bond formation at the proximal N atom. To understand the origin of this divergent selectivity, herein we synthesize and elucidate the electronic structures of a redox series of Fe(NNMe_2) complexes, which serve as spectroscopic models for their reactive protonated congeners. Using a combination of spectroscopies, in concert with density functional theory and correlated ab initio calculations, we evidence one-electron redox noninnocence of the \"NNMe_2\" moiety. Specifically, although two closed-shell configurations of the \"NNR_2\" ligand have been commonly considered in the literature\u2014isodiazene and hydrazido(2\u2212)\u2014we provide evidence suggesting that, in their reduced forms, the present iron complexes are best viewed in terms of an open-shell [NNR_2]^\u2022\u2013ligand coupled antiferromagnetically to the Fe center. This one-electron redox noninnocence resembles that of the classically noninnocent ligand NO and may have mechanistic implications for selectivity in N_2 fixation activity.", "date": "2019-03-04", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "58", "number": "5", "publisher": "American Chemical Society", "pagerange": "3535-3549", "id_number": "CaltechAUTHORS:20190214-104228298", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190214-104228298", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "GM 070757" }, { "agency": "NSF", "grant_number": "CHE-1531940" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.9b00133", "pmcid": "PMC6598684", "primary_object": { "basename": "ic9b00133_si_001.pdf", "url": "https://authors.library.caltech.edu/records/dwnx0-jbv96/files/ic9b00133_si_001.pdf" }, "related_objects": [ { "basename": "nihms-1037227.pdf", "url": "https://authors.library.caltech.edu/records/dwnx0-jbv96/files/nihms-1037227.pdf" } ], "pub_year": "2019", "author_list": "Thompson, Niklas B.; Oyala, Paul H.; et al." }, { "id": "https://authors.library.caltech.edu/records/kahnc-n5z12", "eprint_id": 91992, "eprint_status": "archive", "datestamp": "2023-08-22 01:04:31", "lastmod": "2023-10-19 23:53:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cho-Inha", "name": { "family": "Cho", "given": "Inha" }, "orcid": "0000-0002-7564-5378" }, { "id": "Prier-C-K", "name": { "family": "Prier", "given": "Christopher K." }, "orcid": "0000-0003-0902-1636" }, { "id": "Jia-Zhi-Jun", "name": { "family": "Jia", "given": "Zhi-Jun" }, "orcid": "0000-0002-5143-4875" }, { "id": "Zhang-Ruijie-K", "name": { "family": "Zhang", "given": "Ruijie K." }, "orcid": "0000-0002-7251-5527" }, { "id": "G\u00f6rbe-T", "name": { "family": "G\u00f6rbe", "given": "Tam\u00e1s" } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Enantioselective Aminohydroxylation of Styrenyl Olefins Catalyzed by an Engineered Hemoprotein", "ispublished": "pub", "full_text_status": "public", "keywords": "alkenes; amino alcohols; biocatalysis; directed evolution; heme proteins; nitrenes", "note": "\u00a9 2019 WILEY\u2010VCH Verlag. \n\nManuscript received: November 12, 2018; Accepted manuscript online: January 2, 2019; Version of record online: January 25, 2019. \n\nWe thank Kai Chen and Dr. Xiongyi Huang for helpful discussions and assistance with ee determination. We also thank X.\u2005H. and Dr. Sabine Brinkmann\u2010Chen for proofreading the manuscript. We acknowledge the National Science Foundation, Division of Molecular and Cellular Biosciences (grant MCB\u20101513007) for supporting this work. C.K.P. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. R.K.Z. was supported by a National Science Foundation Graduate Research Fellowship (DGE\u20101144469), the Caltech Biotechnology Leadership Program, and the Donna and Benjamin\u2005M. Rosen Bioengineering Center. Z.\u2010J.J. is supported by the Deutsche Forschungsgemeinschaft (JI 289/1\u20101). T.G. thanks for the financial support of the Stiftelsen Olle Engkvist Byggm\u00e4stare and the Kungl. Skogs\u2010och Lantbruksakademien. \n\nThe authors declare no conflict of interest.\n\n

Supplemental Material - anie201812968-s1-supporting_information.pdf

", "abstract": "Chiral 1,2\u2010amino alcohols are widely represented in biologically active compounds from neurotransmitters to antivirals. While many synthetic methods have been developed for accessing amino alcohols, the direct aminohydroxylation of alkenes to unprotected, enantioenriched amino alcohols remains a challenge. Using directed evolution, we have engineered a hemoprotein biocatalyst based on a thermostable cytochrome c that directly transforms alkenes to amino alcohols with high enantioselectivity (up to 2500 TTN and 90\u2009% ee) under anaerobic conditions with O\u2010pivaloylhydroxylamine as an aminating reagent. The reaction is proposed to proceed via a reactive iron\u2010nitrogen species generated in the enzyme active site, enabling tuning of the catalyst's activity and selectivity by protein engineering.", "date": "2019-03-04", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "58", "number": "10", "publisher": "Wiley", "pagerange": "3138-3142", "id_number": "CaltechAUTHORS:20190102-135256908", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190102-135256908", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Caltech Biotechnology Leadership Program" }, { "agency": "Donna and Benjamin M. Rosen Bioengineering Center" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "JI 289/1\u20101" }, { "agency": "Stiftelsen Olle Engkvist Byggm\u00e4stare" }, { "agency": "Kungl. Skogs-och Lantbruksakademien" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Rosen-Bioengineering-Center" } ] }, "doi": "10.1002/anie.201812968", "primary_object": { "basename": "anie201812968-s1-supporting_information.pdf", "url": "https://authors.library.caltech.edu/records/kahnc-n5z12/files/anie201812968-s1-supporting_information.pdf" }, "pub_year": "2019", "author_list": "Cho, Inha; Prier, Christopher K.; et al." }, { "id": "https://authors.library.caltech.edu/records/q7e4w-nd045", "eprint_id": 92402, "eprint_status": "archive", "datestamp": "2023-08-22 00:59:38", "lastmod": "2023-10-20 00:15:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Huang-Xiongyi", "name": { "family": "Huang", "given": "Xiongyi" }, "orcid": "0000-0001-7156-8881" }, { "id": "Zhang-Shuo-Qing", "name": { "family": "Zhang", "given": "Shuo-Qing" }, "orcid": "0000-0002-7617-3042" }, { "id": "Zhou-Andrew-Z", "name": { "family": "Zhou", "given": "Andrew Z." } }, { "id": "Kan-Sek-Buk-Jennifer", "name": { "family": "Kan", "given": "S. B. Jennifer" }, "orcid": "0000-0001-6371-8042" }, { "id": "Hong-Xin", "name": { "family": "Hong", "given": "Xin" }, "orcid": "0000-0003-4717-2814" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Engineered Cytochrome c-Catalyzed Lactone-Carbene B\u2013H Insertion", "ispublished": "pub", "full_text_status": "public", "keywords": "cytochrome c; carbene; organoboron; lactones; biocatalyst; directed evolution", "note": "\u00a9 2019 Georg Thieme Verlag Stuttgart. Copyright with the author. CC BY ND NC 4.0. \n\nPublished as part of the 30 Years SYNLETT \u2013 Pearl Anniversary Issue. \n\nFinancial support from the NSF Division of Molecular and Cellular Biosciences grant MCB-1513007, National Natural Science Foundation of China (21702182), Zhejiang University, the Chinese \"Thousand Youth Talents Plan\", and the \"Fundamental Research Funds for the Central Universities\" is gratefully acknowledged. K.C. thanks the Resnick Sustainability Institute at Caltech for fellowship support. X.H. is supported by an NIH pathway to independence award (grant K99GM129419). \n\nA.Z.Z. thanks the Caltech SURF program. Calculations were performed on the high-performance computing system at the Department of Chemistry, Zhejiang University. We thank R. D. Lewis and R. K. Zhang for helpful discussions and comments. We also thank the Caltech Mass Spectrometry Laboratory.\n\n

Published - s-0037-1611662.pdf

Accepted Version - nihms-1013872.pdf

Supplemental Material - sup_st-2018-b0769-l_10-1055_s-0037-1611662.pdf

", "abstract": "Previous work has demonstrated that variants of a heme protein, Rhodothermus marinus cytochrome c (Rma cyt c), catalyze abiological carbene boron\u2013hydrogen (B\u2013H) bond insertion with high efficiency and selectivity. Here we investigated this carbon\u2013boron bond-forming chemistry with cyclic, lactone-based carbenes. Using directed evolution, we obtained a Rma cyt c variant BOR^(LAC) that shows high selectivity and efficiency for B\u2013H insertion of 5- and 6-membered lactone carbenes (up to 24,500 total turnovers and 97.1:2.9 enantiomeric ratio). The enzyme shows low activity with a 7-membered lactone carbene. Computational studies revealed a highly twisted geometry of the 7-membered lactone carbene intermediate relative to 5- and 6-membered ones. Directed evolution of cytochrome c together with computational characterization of key iron-carbene intermediates has allowed us to expand the scope of enzymatic carbene B\u2013H insertion to produce new lactone-based organoborons.", "date": "2019-03", "date_type": "published", "publication": "Synlett", "volume": "30", "number": "4", "publisher": "Georg Thieme Verlag", "pagerange": "378-382", "id_number": "CaltechAUTHORS:20190122-134051110", "issn": "0936-5214", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190122-134051110", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21702182" }, { "agency": "Zhejiang University" }, { "agency": "1000 Young Talents Program" }, { "agency": "Fundamental Research Funds for the Central Universities" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "K99GM129419" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1055/s-0037-1611662", "pmcid": "PMC6436545", "primary_object": { "basename": "nihms-1013872.pdf", "url": "https://authors.library.caltech.edu/records/q7e4w-nd045/files/nihms-1013872.pdf" }, "related_objects": [ { "basename": "s-0037-1611662.pdf", "url": "https://authors.library.caltech.edu/records/q7e4w-nd045/files/s-0037-1611662.pdf" }, { "basename": "sup_st-2018-b0769-l_10-1055_s-0037-1611662.pdf", "url": "https://authors.library.caltech.edu/records/q7e4w-nd045/files/sup_st-2018-b0769-l_10-1055_s-0037-1611662.pdf" } ], "pub_year": "2019", "author_list": "Chen, Kai; Huang, Xiongyi; et al." }, { "id": "https://authors.library.caltech.edu/records/p3g6h-zy515", "eprint_id": 92766, "eprint_status": "archive", "datestamp": "2023-08-19 14:21:37", "lastmod": "2025-04-25 23:07:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lionetti-Davide", "name": { "family": "Lionetti", "given": "Davide" }, "orcid": "0000-0002-4937-886X" }, { "id": "Suseno-Sandy", "name": { "family": "Suseno", "given": "Sandy" } }, { "id": "Tsui-Emily-Y", "name": { "family": "Tsui", "given": "Emily Y." }, "orcid": "0000-0001-6419-3954" }, { "id": "Lu-Luo", "name": { "family": "Lu", "given": "Luo" } }, { "id": "Stich-Ttoy-A", "name": { "family": "Stich", "given": "Troy A." }, "orcid": "0000-0003-0710-1456" }, { "id": "Carsch-Kurtis-M", "name": { "family": "Carsch", "given": "Kurtis M." }, "orcid": "0000-0003-4432-7518" }, { "id": "Nielsen-Robert-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Britt-R-David", "name": { "family": "Britt", "given": "R. David" }, "orcid": "0000-0003-0889-8436" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Effects of Lewis Acidic Metal Ions (M) on Oxygen-Atom Transfer Reactivity of Heterometallic Mn\u2083MO\u2084 Cubane and Fe\u2083MO(OH) and Mn\u2083MO(OH) Clusters", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: September 21, 2018. Publication Date (Web): February 7, 2019. \n\nAccession Codes: CCDC 1035166 and 1035222 contain the supplementary crystallographic data for this paper. \n\nThis work was supported by the California Institute of Technology and the NIH R01 GM102687A (T.A.). T.A. is a Dreyfus fellow. We thank Dr. Michael K. Takase and Lawrence M. Henling for assistance with X-ray crystallography. D.L. gratefully acknowledges a graduate fellowship from the Resnick Sustainability Institute at Caltech. K.C. and W.A.G. received support from the NSF (CBET-1512759). The Bruker KAPPA APEXII X-ray diffractometer was purchased via an NSF Chemistry Research Instrumentation award to Caltech (CHE-0639094). Computational resources included the Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation Grant ACI-1548562. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1023538.pdf

Supplemental Material - ic8b02701_si_001.pdf

", "abstract": "The modulation of the reactivity of metal oxo species by redox inactive metals has attracted much interest due to the observation of redox inactive metal effects on processes involving electron transfer both in nature (the oxygen-evolving complex of Photosystem II) and in heterogeneous catalysis (mixed-metal oxides). Studies of small-molecule models of these systems have revealed numerous instances of effects of redox inactive metals on electron- and group-transfer reactivity. However, the heterometallic species directly involved in these transformations have rarely been structurally characterized and are often generated in situ. We have previously reported the preparation and structural characterization of multiple series of heterometallic clusters based on Mn\u2083 and Fe\u2083 cores and described the effects of Lewis acidity of the heterometal incorporated in these complexes on cluster reduction potential. To determine the effects of Lewis acidity of redox inactive metals on group transfer reactivity in structurally well-defined complexes, we studied [Mn\u2083MO_\u2084, [Mn\u2083MO(OH)], and [Fe\u2083MO(OH)] clusters in oxygen atom transfer (OAT) reactions with phosphine substrates. The qualitative rate of OAT correlates with the Lewis acidity of the redox inactive metal, confirming that Lewis acidic metal centers can affect the chemical reactivity of metal oxo species by modulating cluster electronics.", "date": "2019-02-18", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "58", "number": "4", "publisher": "American Chemical Society", "pagerange": "2336-2345", "id_number": "CaltechAUTHORS:20190207-142044105", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190207-142044105", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "NIH", "grant_number": "R01 GM102687A" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "NSF", "grant_number": "CHE-0639094" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1324", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.8b02701", "pmcid": "PMC6574207", "primary_object": { "basename": "ic8b02701_si_001.pdf", "url": "https://authors.library.caltech.edu/records/p3g6h-zy515/files/ic8b02701_si_001.pdf" }, "related_objects": [ { "basename": "nihms-1023538.pdf", "url": "https://authors.library.caltech.edu/records/p3g6h-zy515/files/nihms-1023538.pdf" } ], "pub_year": "2019", "author_list": "Lionetti, Davide; Suseno, Sandy; et al." }, { "id": "https://authors.library.caltech.edu/records/jz8e1-0kn48", "eprint_id": 92455, "eprint_status": "archive", "datestamp": "2023-08-19 14:19:24", "lastmod": "2023-10-20 15:43:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Teh-Ying-Shi", "name": { "family": "Teh", "given": "Ying Shi" }, "orcid": "0000-0003-1743-4158" }, { "id": "Bhattacharya-K", "name": { "family": "Bhattacharya", "given": "Kaushik" }, "orcid": "0000-0003-2908-5469" } ] }, "title": "Photovoltaic effect in multi-domain ferroelectric perovskite oxides", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published under license by AIP Publishing. \n\nSubmitted: 29 November 2018; Accepted: 24 January 2019; Published Online: 13 February 2019. \n\nYing Shi Teh gratefully acknowledges the support of the Resnick Institute at Caltech through the Resnick Graduate Research Fellowship.\n\n

Published - 1.5083632.pdf

Submitted - 1811.07948.pdf

", "abstract": "We propose a device model that elucidates the role of domain walls in the photovoltaic effect in multi-domain ferroelectric perovskites. The model accounts for the intricate interplay between ferroelectric polarization, space charges, photo-generation, and electronic transport. When applied to bismuth ferrite, results show a significant electric potential step across both 71\u00b0 and 109\u00b0 domain walls, which in turn contributes to the photovoltaic (PV) effect. We also find a strong correlation between polarization and oxygen octahedra tilts, which indicates the nontrivial role of the latter in the PV effect. The domain wall-based PV effect is further shown to be additive in nature, allowing for the possibility of generating the above-bandgap voltage.", "date": "2019-02-14", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "125", "number": "6", "publisher": "American Institute of Physics", "pagerange": "Art. No. 064103", "id_number": "CaltechAUTHORS:20190124-122550312", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190124-122550312", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.5083632", "primary_object": { "basename": "1.5083632.pdf", "url": "https://authors.library.caltech.edu/records/jz8e1-0kn48/files/1.5083632.pdf" }, "related_objects": [ { "basename": "1811.07948.pdf", "url": "https://authors.library.caltech.edu/records/jz8e1-0kn48/files/1811.07948.pdf" } ], "pub_year": "2019", "author_list": "Teh, Ying Shi and Bhattacharya, Kaushik" }, { "id": "https://authors.library.caltech.edu/records/tb3v8-fkw52", "eprint_id": 91499, "eprint_status": "archive", "datestamp": "2023-08-19 14:11:45", "lastmod": "2023-10-19 22:32:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naviaux-J-D", "name": { "family": "Naviaux", "given": "John D." } }, { "id": "Subhas-A-V", "name": { "family": "Subhas", "given": "Adam V." }, "orcid": "0000-0002-7688-6624" }, { "id": "Rollins-N-E", "name": { "family": "Rollins", "given": "Nick E." } }, { "id": "Dong-Sijia-S", "name": { "family": "Dong", "given": "Sijia" }, "orcid": "0000-0002-5811-9333" }, { "id": "Berelson-W-M", "name": { "family": "Berelson", "given": "William M." } }, { "id": "Adkins-J-F", "name": { "family": "Adkins", "given": "Jess F." }, "orcid": "0000-0002-3174-5190" } ] }, "title": "Temperature Dependence of Calcite Dissolution Kinetics in Seawater", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 Published by Elsevier Ltd. \n\nReceived 1 August 2018, Revised 26 November 2018, Accepted 27 November 2018, Available online 5 December 2018. \n\nWe would like to thank the anonymous journal reviewers as well as Oleg Pokrovsky and Henry Teng for the insightful comments and suggestions they gave that helped to improve this manuscript. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1745301, as well as NSF grant Numbers OCE1220302, OCE1559004 and 1559215. John Naviaux and Adam Subhas would also like to thank the Resnick Sustainability Institute at Caltech for fellowship support.\n\n

Supplemental Material - 1-s2.0-S0016703718306677-mmc1.docx

", "abstract": "Knowledge of calcite dissolution kinetics in seawater is a critical component of our understanding of the changing global carbon budget. Towards this goal, we provide the first measurements of the temperature dependence of calcite dissolution kinetics in seawater. We measured the dissolution rates of ^(13)C-labeled calcite in seawater at 5, 12, 21, and 37\u00b0C across the full range of saturation states (0 < \u03a9 = Ca^(2+)[CO_3^(2-)/Ksp'< 1). We show that the dissolution rate is non-linearly dependent on \u03a9 and that the degree of non-linearity both increases with temperature, and changes abruptly at \"critical\" saturation states (\u03a9_(crit_). The traditional exponential rate law most often utilized in the oceanographic community, R=k(1-\u03a9)^n, requires different fits to k and n depending upon the degree of undersaturation. Though we calculate a similar activation energy to other studies far from equilibrium (25\u00b12 kJ/mol), the exponential rate law could not be used to mechanistically explain our near equilibrium results. We turn to an alternative framework, derived from crystal nucleation theory, and find that our results are consistent with calcite dissolution kinetics in seawater being set by the retreat of pre-existing edges/steps from \u03a9=1-0.9, defect-assisted etch pit formation from \u03a9=0.9-0.75, and finally homogenous etch pit formation from \u03a9=0.75-0. The \u03a9_(crit) s for each mechanism are shifted significantly closer to equilibrium than they occur in dilute solutions, such that ocean acidification may cause marine carbonates to enter faster dissolution regimes more readily than would be expected from previous studies. We use the observed temperature dependence for each dissolution mechanism to calculate step kinetic coefficients (\u03b2, cm/s), densities of active nucleation sites (n_s, sites/m^2), and step edge free energies (\u03b1, mJ/m^2). Homogenous dissolution is well explained within the surface nucleation framework, but defect-assisted dissolution is not. Dissolution is initiated via step-propagation at all temperatures, but the defect-assisted mechanism is skipped over at 5\u00b0C, potentially due to a lack of nucleation sites. The surface nucleation framework enhances our understanding of calcite dissolution in seawater, but our results suggest that a complete theory will also need to incorporate the role of solution/surface speciation and complexation.", "date": "2019-02-01", "date_type": "published", "publication": "Geochimica et Cosmochimica Acta", "volume": "246", "publisher": "Elsevier", "pagerange": "363-384", "id_number": "CaltechAUTHORS:20181205-100011581", "issn": "0016-7037", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181205-100011581", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "OCE-1220302" }, { "agency": "NSF", "grant_number": "OCE-1559004" }, { "agency": "NSF", "grant_number": "OCE-1559215" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.gca.2018.11.037", "primary_object": { "basename": "1-s2.0-S0016703718306677-mmc1.docx", "url": "https://authors.library.caltech.edu/records/tb3v8-fkw52/files/1-s2.0-S0016703718306677-mmc1.docx" }, "pub_year": "2019", "author_list": "Naviaux, John D.; Subhas, Adam V.; et al." }, { "id": "https://authors.library.caltech.edu/records/am307-0sa03", "eprint_id": 90161, "eprint_status": "archive", "datestamp": "2023-08-22 00:41:26", "lastmod": "2023-10-18 23:15:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mi-Zhifu", "name": { "family": "Mi", "given": "Zhifu" }, "orcid": "0000-0001-8106-0694" }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Liu-Jingru", "name": { "family": "Liu", "given": "Jingru" } }, { "id": "Vigui\u00e9-V", "name": { "family": "Vigui\u00e9", "given": "Vincent" } }, { "id": "Fromer-N-A", "name": { "family": "Fromer", "given": "Neil" } }, { "id": "Wang-Yutao", "name": { "family": "Wang", "given": "Yutao" } } ] }, "title": "Cities: the core of climate change mitigation", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate change; mitigation; city; emission inventory; sustainable development", "note": "\u00a9 2018 Elsevier. \n\nReceived 12 April 2018, Revised 1 October 2018, Accepted 5 October 2018, Available online 6 October 2018.", "abstract": "Cities, the core of the global climate change mitigation and strategic low-carbon development, are shelters to more than half of the world population and responsible for three quarters of global energy consumption and greenhouse gas (GHG). This special volume (SV) provides a platform that promotes multi- and inter- disciplinary analyses and discussions on the climate change mitigation for cities. All papers are divided into several themes, including GHG emission inventory and accounting, climate change and urban sectors, climate change and sustainable development, and strategies and mitigation action plans. First, this SV provides methods for constructing emission inventory from both production and consumption perspectives. These methods are useful to improve the comprehensiveness and accuracy of carbon accounting for international cities. Second, the climate change affects urban sectors from various aspects; simultaneously, GHG emissions caused by activities in urban sectors affect the climate system. This SV focuses on mitigation policies and assessment in energy, transport, construction, and service sectors. Third, climate change mitigation of cities is closely connected to urban sustainable development. This SV explores the relationships between climate change mitigation with urbanization, ecosystems, air pollution, and extreme events. Fourth, climate change mitigation policies can be divided into two categories: quantity-based mechanism (e.g., carbon emission trading) and price-based mechanism (e.g., carbon tax). This SV provides experiences of local climate change mitigation all over the world and proposes the city-to-city cooperation on climate change mitigation.", "date": "2019-01-10", "date_type": "published", "publication": "Journal of Cleaner Production", "volume": "207", "publisher": "Elsevier", "pagerange": "582-589", "id_number": "CaltechAUTHORS:20181008-145630226", "issn": "0959-6526", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181008-145630226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.jclepro.2018.10.034", "pub_year": "2019", "author_list": "Mi, Zhifu; Guan, Dabo; et al." }, { "id": "https://authors.library.caltech.edu/records/hs72f-tsg03", "eprint_id": 91588, "eprint_status": "archive", "datestamp": "2023-08-19 13:49:36", "lastmod": "2025-04-23 03:10:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sherrott-M-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Whitney-W-S", "name": { "family": "Whitney", "given": "William S." }, "orcid": "0000-0001-5269-2967" }, { "id": "Jariwala-D", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Biswas-S", "name": { "family": "Biswas", "given": "Souvik" } }, { "id": "Went-C-M", "name": { "family": "Went", "given": "Cora M." } }, { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Rossman-G-R", "name": { "family": "Rossman", "given": "George R." }, "orcid": "0000-0002-4571-6884" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Anisotropic Quantum Well Electro-Optics in Few-Layer Black Phosphorus", "ispublished": "pub", "full_text_status": "public", "keywords": "Electro-optic tunability, black phosphorus, broadband, anisotropy, van der Waals materials", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: September 25, 2018; Revised: December 5, 2018; Published: December 7, 2018. \n\nThe authors gratefully acknowledge support from the Department of Energy, Office of Science (DE-FG02-07ER46405) and for facilities of the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (DE-SC0001293). W.S.W. also acknowledges support from an NDSEG Graduate Research Fellowship. M.C.S., D.J., and C.M.W. acknowledge fellowship support from the Resnick Institute. J.W. acknowledges support from the National Science Foundation Graduate Research Fellowship (1144469). \n\nAuthor Contributions: M.C.S. and W.S.W contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl8b03876_si_001.pdf

", "abstract": "The incorporation of electrically tunable materials into photonic structures such as waveguides and metasurfaces enables dynamic, electrical control of light propagation at the nanoscale. Few-layer black phosphorus is a promising material for these applications due to its in-plane anisotropic, quantum well band structure, with a direct band gap that can be tuned from 0.3 to 2 eV with a number of layers and subbands that manifest as additional optical transitions across a wide range of energies. In this Letter, we report an experimental investigation of three different, anisotropic electro-optic mechanisms that allow electrical control of the complex refractive index in few-layer black phosphorus from the mid-infrared to the visible: Pauli-blocking of intersubband optical transitions (the Burstein\u2013Moss effect); the quantum-confined Stark effect; and the modification of quantum well selection rules by a symmetry-breaking, applied electric field. These effects generate near-unity tuning of the BP oscillator strength for some material thicknesses and photon energies, along a single in-plane crystal axis, transforming absorption from highly anisotropic to nearly isotropic. Lastly, the anisotropy of these electro-optical phenomena results in dynamic control of linear dichroism and birefringence, a promising concept for active control of the complex polarization state of light, or propagation direction of surface waves.", "date": "2019-01-09", "date_type": "published", "publication": "Nano Letters", "volume": "19", "number": "1", "publisher": "American Chemical Society", "pagerange": "269-276", "id_number": "CaltechAUTHORS:20181207-153407209", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181207-153407209", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.nanolett.8b03876", "primary_object": { "basename": "nl8b03876_si_001.pdf", "url": "https://authors.library.caltech.edu/records/hs72f-tsg03/files/nl8b03876_si_001.pdf" }, "pub_year": "2019", "author_list": "Sherrott, Michelle C.; Whitney, William S.; et al." }, { "id": "https://authors.library.caltech.edu/records/yp0mg-1ps72", "eprint_id": 91946, "eprint_status": "archive", "datestamp": "2023-08-19 13:48:22", "lastmod": "2023-10-19 23:51:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ngo-Danh-X", "name": { "family": "Ngo", "given": "Danh X." } }, { "id": "Kramer-W-W", "name": { "family": "Kramer", "given": "Wesley W." } }, { "id": "McNicholas-B-J", "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Brennan-B-J", "name": { "family": "Brennan", "given": "Bradley J." } } ] }, "title": "Structure, Spectroscopy, and Electrochemistry of Manganese(I) and Rhenium(I) Quinoline Oximes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: October 13, 2018; Published: December 21, 2018.\n\nWe thank Larry Henling, Michael Takase, David VanderVelde, Mona Shahgholi, and Naseem Torian for experimental assistance and discussions. \n\nThis work was funded by NSF CCI Solar Fuels (CHE-130124). Additional support was provided by the Resnick Sustainability Institute at Caltech and a Dr. and Mrs. Daniel C. Harris SURF Fellowship. \n\nAccession Codes: CCDC 1567369\u20131567373 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44 1223 336033. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ic8b02862_si_001.pdf

", "abstract": "Reactions of \u03b1- and \u03b2-diimine quinoline aldoximes with Mn(I) and Re(I) tricarbonyl halides afford quinoline oxime complexes. Both Mn(I) and Re(I) complexes experience severe geometric strain due to ligand steric interactions: 6-membered metallocycles exhibit more pronounced distortions than 5-membered ones, consistent with density functional theory structural analyses. Such distortions likely also affect reactivity patterns, as evidenced by Re(I)-induced deoximation of a quinoline variant containing a CF_3-ketoxime.", "date": "2019-01-07", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "58", "number": "1", "publisher": "American Chemical Society", "pagerange": "737-746", "id_number": "CaltechAUTHORS:20181221-091725545", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181221-091725545", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-130124" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.8b02862", "primary_object": { "basename": "ic8b02862_si_001.pdf", "url": "https://authors.library.caltech.edu/records/yp0mg-1ps72/files/ic8b02862_si_001.pdf" }, "pub_year": "2019", "author_list": "Ngo, Danh X.; Kramer, Wesley W.; et al." }, { "id": "https://authors.library.caltech.edu/records/8p281-9rt86", "eprint_id": 91853, "eprint_status": "archive", "datestamp": "2023-08-19 13:45:01", "lastmod": "2023-10-19 23:46:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Finke-Cody-E", "name": { "family": "Finke", "given": "Cody E." }, "orcid": "0000-0002-1343-1737" }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Jasper-Justin-T", "name": { "family": "Jasper", "given": "Justin T." }, "orcid": "0000-0002-2461-5283" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Read-Carlos-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" } ] }, "title": "Enhancing the activity of oxygen-evolution and chlorine-evolution electrocatalysts by atomic layer deposition of TiO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. \n\nThe article was received on 12 Aug 2018, accepted on 26 Nov 2018 and first published on 14 Dec 2018. \n\nSupporting data referenced above may be found in the ESI. This work was supported by the Bill and Melinda Gates Foundation (BMGF RTTC Grants OPP1111246 and OPP1149755). Research was in part carried out at the Molecular Materials Resource Center of the Beckman Institute of the California Institute of Technology. Funding was provided to C. E. F., J. T. J., and C. G. R. by the Resnick Institute for Sustainability at Caltech. In part, this material is based upon work by S. T. O. and N. S. L. performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. C. E. F. was the primary concept generator for this work, led electrocatalyst activity, E_(ZC), and AFM data collection and analysis, and helped fabricate and characterize the electrocatalysts. S. T. O. helped to generate the concept for this work, fabricated and characterized the electrocatalysts, and helped with data analysis and experimental design. J. T. J. helped generate the concept of this work, helped design the electrochemical methodology, and helped collect electrochemical data. M. F. L. collected the XPS data and assisted in the fitting and analysis of XPS and impedance spectroscopy data. C. G. R. lead TEM characterization of the electro catalysts. C. E. F., S. T. O., and J. T. J. prepared the manuscript and N. S. L., M. R. H., M. F. L., and C. G. R. helped with its editing. All authors reviewed and contributed to the final manuscript. We would like to acknowledge Dr Katharina Urmann and Sisir Yalamanchili for help dicing Si wafers, Jingjing Jiang for help analyzing AFM data, and Azhar Carim for help with SEM, and Laleh Majari Kasmaee for help with E_(ZC) analysis. We acknowledge Prof. Stefan Zweifel and his group for foundational mentoring as well as Prof. Gretchen Hofmeister and Prof. Matt Whited for foundational chemical insight. \n\nConflicts of interest: The authors' institution (California Institute of Technology) has filed a U.S. patent application directly relating to the work described in the paper (patent application no. US20180087164A1, filed on Sept. 28, 2017).\n\n

Published - c8ee02351d.pdf

Supplemental Material - c8ee02351d1_si.pdf

", "abstract": "We report that TiO\u2082 coatings formed via atomic layer deposition (ALD) may tune the activity of IrO\u2082, RuO\u2082, and FTO for the oxygen-evolution and chlorine-evolution reactions (OER and CER). Electrocatalysts exposed to \u223c3\u201330 ALD cycles of TiO\u2082 exhibited overpotentials at 10 mA cm\u207b\u00b2 of geometric current density that were several hundred millivolts lower than uncoated catalysts, with correspondingly higher specific activities. For example, the deposition of TiO\u2082 onto IrO\u2082 yielded a 9-fold increase in the OER-specific activity in 1.0 M H\u2082SO\u2084 (0.1 to 0.9 mA cm_(ECSA)\u207b\u00b2 at 350 mV overpotential). The oxidation state of titanium and the potential of zero charge were also a function of the number of ALD cycles, indicating a correlation between oxidation state, potential of zero charge, and activity of the tuned electrocatalysts.", "date": "2019-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "12", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "358-365", "id_number": "CaltechAUTHORS:20181217-085437866", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-085437866", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1111246" }, { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1149755" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c8ee02351d", "pmcid": "PMC7680952", "primary_object": { "basename": "c8ee02351d1_si.pdf", "url": "https://authors.library.caltech.edu/records/8p281-9rt86/files/c8ee02351d1_si.pdf" }, "related_objects": [ { "basename": "c8ee02351d.pdf", "url": "https://authors.library.caltech.edu/records/8p281-9rt86/files/c8ee02351d.pdf" } ], "pub_year": "2019", "author_list": "Finke, Cody E.; Omelchenko, Stefan T.; et al." }, { "id": "https://authors.library.caltech.edu/records/nfa0z-bj537", "eprint_id": 90158, "eprint_status": "archive", "datestamp": "2023-08-19 13:25:13", "lastmod": "2023-10-18 23:14:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Almhjell-Patrick-J", "name": { "family": "Almhjell", "given": "Patrick J." }, "orcid": "0000-0003-0977-841X" }, { "id": "Boville-Christina-E", "name": { "family": "Boville", "given": "Christina E." }, "orcid": "0000-0002-2577-9343" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Engineering enzymes for noncanonical amino acid synthesis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nThe article was received on 12 Aug 2018 and first published on 03 Oct 2018. \n\nThe authors would like to thank Dr Sabine Brinkmann-Chen, Dr David Romney, Prof. Andrew Buller, and Bradley Boville for helpful discussion and comments on the manuscript. C. E. B. was supported by a postdoctoral fellowship from the Resnick Sustainability Institute. This work was funded by the Jacobs Institute for Molecular Engineering for Medicine (Caltech) and the Rothenberg Innovation Initiative (formerly CI2), and by the National Institute Of General Medical Sciences of the National Institutes of Health under Award Number R01GM125887. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. \n\nThere are no conflicts to declare.\n\n

Accepted Version - nihms-1013607.pdf

", "abstract": "The standard proteinogenic amino acids grant access to a myriad of chemistries that harmonize to create life. Outside of these twenty canonical protein building blocks are countless noncanonical amino acids (ncAAs), either found in nature or created by man. Interest in ncAAs has grown as research has unveiled their importance as precursors to natural products and pharmaceuticals, biological probes, and more. Despite their broad applications, synthesis of ncAAs remains a challenge, as poor stereoselectivity and low functional-group compatibility stymie effective preparative routes. The use of enzymes has emerged as a versatile approach to prepare ncAAs, and nature's enzymes can be engineered to synthesize ncAAs more efficiently and expand the amino acid alphabet. In this tutorial review, we briefly outline different enzyme engineering strategies and then discuss examples where engineering has generated new 'ncAA synthases' for efficient, environmentally benign production of a wide and growing collection of valuable ncAAs.", "date": "2018-12-21", "date_type": "published", "publication": "Chemical Society Reviews", "volume": "47", "number": "24", "publisher": "Royal Society of Chemistry", "pagerange": "8980-8997", "id_number": "CaltechAUTHORS:20181008-141850453", "issn": "0306-0012", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181008-141850453", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Jacobs Institute for Molecular Engineering for Medicine" }, { "agency": "Rothenberg Innovation Initiative (RI2)" }, { "agency": "NIH", "grant_number": "R01GM125887" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Jacobs-Institute-for-Molecular-Engineering-for-Medicine" } ] }, "doi": "10.1039/c8cs00665b", "pmcid": "PMC6434697", "primary_object": { "basename": "nihms-1013607.pdf", "url": "https://authors.library.caltech.edu/records/nfa0z-bj537/files/nihms-1013607.pdf" }, "pub_year": "2018", "author_list": "Almhjell, Patrick J.; Boville, Christina E.; et al." }, { "id": "https://authors.library.caltech.edu/records/sjp0n-vnz35", "eprint_id": 92184, "eprint_status": "archive", "datestamp": "2023-08-19 13:26:33", "lastmod": "2023-10-20 00:03:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Xuan-Yi", "name": { "family": "Xuan", "given": "Yi" } }, { "id": "Wang-Cong", "name": { "family": "Wang", "given": "Cong" } }, { "id": "F\u00fcl\u00f6p-A", "name": { "family": "F\u00fcl\u00f6p", "given": "Attila" } }, { "id": "Leaird-D-E", "name": { "family": "Leaird", "given": "Daniel E." } }, { "id": "Torres-Company-V", "name": { "family": "Torres-Company", "given": "Victor" } }, { "id": "Qi-Minghao", "name": { "family": "Qi", "given": "Minghao" } }, { "id": "Weiner-A-M", "name": { "family": "Weiner", "given": "Andrew M." }, "orcid": "0000-0002-1334-8183" } ] }, "title": "Observation of Breathing Dark Pulses in Normal Dispersion Optical Microresonators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Physical Society. \n\nReceived 8 June 2018; published 21 December 2018. \n\nThis Letter was supported in part by the Air Force Office of Scientific Research (Grant No. FA9550-15-1-0211), by the DARPA PULSE program (Grant No. W31P4Q-13-1-0018) from AMRDEC, and by the National Science Foundation (Grant No. ECCS-1509578). A.\u2009F. and V.\u2009T.\u2009C. acknowledge partial support by the Swedish Research Council and the European Research Council (DarkComb Grant Agreement No. 771410). C.\u2009B. acknowledge partial support from a postdoctoral fellowship from the Resnick Institute, Caltech. We gratefully acknowledge fruitful discussions with Xiaoxiao Xue, Nail Akhmediev, Zhen Qi, and Curtis Menyuk.\n\n

Published - PhysRevLett.121.257401.pdf

Submitted - 1709.03912.pdf

Supplemental Material - Animation1.mp4

Supplemental Material - Animation2.mp4

Supplemental Material - darkbreather_SI_R2Submission.pdf

", "abstract": "Breathers are localized waves in nonlinear systems that undergo a periodic variation in time or space. The concept of breathers is useful for describing many nonlinear physical systems including granular lattices, Bose-Einstein condensates, hydrodynamics, plasmas, and optics. In optics, breathers can exist in either the anomalous or the normal dispersion regimes, but they have only been characterized in the former, to our knowledge. Here, externally pumped optical microresonators are used to characterize the breathing dynamics of localized waves in the normal dispersion regime. High-\nQ\n optical microresonators featuring normal dispersion can yield mode-locked Kerr combs whose time-domain waveform corresponds to circulating dark pulses in the cavity. We show that with relatively high pump power these Kerr combs can enter a breathing regime, in which the time-domain waveform remains a dark pulse but experiences a periodic modulation on a time scale much slower than the microresonator round trip time. The breathing is observed in the optical frequency domain as a significant difference in the phase and amplitude of the modulation experienced by different spectral lines. In the highly pumped regime, a transition to a chaotic breathing state where the waveform remains dark-pulse-like is also observed, for the first time to our knowledge; such a transition is reversible by reducing the pump power.", "date": "2018-12-21", "date_type": "published", "publication": "Physical Review Letters", "volume": "121", "number": "25", "publisher": "American Physical Society", "pagerange": "Art. No. 257401", "id_number": "CaltechAUTHORS:20190109-155711201", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190109-155711201", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-15-1-0211" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W31P4Q-13-1-0018" }, { "agency": "NSF", "grant_number": "ECCS-1509578" }, { "agency": "Svenska Forskningsr\u00e5det Formas" }, { "agency": "European Research Council (ERC)", "grant_number": "771410" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/physrevlett.121.257401", "primary_object": { "basename": "1709.03912.pdf", "url": "https://authors.library.caltech.edu/records/sjp0n-vnz35/files/1709.03912.pdf" }, "related_objects": [ { "basename": "Animation1.mp4", "url": "https://authors.library.caltech.edu/records/sjp0n-vnz35/files/Animation1.mp4" }, { "basename": "Animation2.mp4", "url": "https://authors.library.caltech.edu/records/sjp0n-vnz35/files/Animation2.mp4" }, { "basename": "darkbreather_SI_R2Submission.pdf", "url": "https://authors.library.caltech.edu/records/sjp0n-vnz35/files/darkbreather_SI_R2Submission.pdf" }, { "basename": "PhysRevLett.121.257401.pdf", "url": "https://authors.library.caltech.edu/records/sjp0n-vnz35/files/PhysRevLett.121.257401.pdf" } ], "pub_year": "2018", "author_list": "Bao, Chengying; Xuan, Yi; et al." }, { "id": "https://authors.library.caltech.edu/records/yftzt-nch74", "eprint_id": 91540, "eprint_status": "archive", "datestamp": "2023-08-19 13:11:59", "lastmod": "2023-10-19 23:10:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Davis-Victoria-K", "name": { "family": "Davis", "given": "Victoria K." }, "orcid": "0000-0002-6687-5868" }, { "id": "Bates-Christopher-M", "name": { "family": "Bates", "given": "Christopher M." }, "orcid": "0000-0002-1598-794X" }, { "id": "Omichi-Kaoru", "name": { "family": "Omichi", "given": "Kaoru" } }, { "id": "Savoie-Brett-M", "name": { "family": "Savoie", "given": "Brett M." }, "orcid": "0000-0002-7039-4039" }, { "id": "Mom\u010dilovi\u0107-Neboj\u0161a", "name": { "family": "Mom\u010dilovi\u0107", "given": "Neboj\u0161a" } }, { "id": "Xu-Qingmin", "name": { "family": "Xu", "given": "Qingmin" } }, { "id": "Wolf-William-J", "name": { "family": "Wolf", "given": "William J." }, "orcid": "0000-0001-6755-8920" }, { "id": "Webb-Michael-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Billings-Selim-J", "name": { "family": "Billings", "given": "Keith J." } }, { "id": "Chou-Nam-Hawn", "name": { "family": "Chou", "given": "Nam Hawn" } }, { "id": "Alayoglu-Selim", "name": { "family": "Alayoglu", "given": "Selim" } }, { "id": "McKenney-Ryan-K", "name": { "family": "McKenney", "given": "Ryan K." } }, { "id": "Darolles-Isabelle-M", "name": { "family": "Darolles", "given": "Isabelle M." } }, { "id": "Nair-Nanditha-G", "name": { "family": "Nair", "given": "Nanditha G." } }, { "id": "Hightower-Adrian", "name": { "family": "Hightower", "given": "Adrian" } }, { "id": "Rosenberg-Daniel", "name": { "family": "Rosenberg", "given": "Daniel" } }, { "id": "Ahmed-Musahid", "name": { "family": "Ahmed", "given": "Musahid" } }, { "id": "Brooks-Christopher-J", "name": { "family": "Brooks", "given": "Christopher J." } }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" }, { "id": "Jones-Simon-C", "name": { "family": "Jones", "given": "Simon C." }, "orcid": "0000-0002-1952-3720" } ] }, "title": "Room-temperature cycling of metal fluoride electrodes: Liquid electrolytes for high-energy fluoride ion cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works http://www.sciencemag.org/about/science-licenses-journal-article-reuse. This is an article distributed under the terms of the Science Journals Default License. \n\nReceived for publication March 28, 2018. Resubmitted August 6, 2018. Accepted for publication October 31, 2018. \n\nThis work is dedicated to the memory of Neboj\u0161a Mom\u010dilovi\u0107. \n\nThe research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. V.K.D. thanks the NSF Graduate Research Fellowship Program for support under grant NSF-DGE-1650116. T.F.M. acknowledges NSF under DMREF award NSF-CHE-1335486. M.A.W. acknowledges the Resnick Sustainability Institute. This research used computational resources from the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy (DOE) under contract DE-AC05-00OR22725. This research also used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the DOE Office of Science under contract DE-AC02-05CH11231. STEM/EELS work at the Molecular Foundry was supported by the DOE Office of Science, Office of Basic Energy Sciences, under contract DE-AC02-05CH11231. We acknowledge support from the Beckman Institute of the California Institute of Technology to the Molecular Materials Research Center. \n\nAuthor contributions: The project was conceptualized by S.C.J. and supervised by K.O., C.J.B., R.H.G., and S.C.J.; fluoride salt synthesis procedures were developed and performed by V.K.D., C.M.B., N.M., I.M.D., and N.G.N.; salt characterization, analysis and solvent screening was performed by V.K.D., C.M.B., and N.M.; ionic conductivity and voltage window studies were performed by V.K.D. and K.J.B.; PFG-SE NMR experiments and analysis was carried out by W.J.W. and V.K.D.; computational studies were performed by B.M.S. and M.A.W. under the supervision of T.F.M.; electrochemical cells were built and tested by Q.X., N.H.C., and K.O.; cathode materials were synthesized by R.K.M.; TEM, EDS, and pXRD was performed by Q.X.; EELS was performed by S.A., D.R., and M.A.; V.K.D. and A.H. performed XPS measurements; V.K.D. made all figures in the main paper and in the supplement; and the manuscript was written by V.K.D. with input from S.C.J. and all authors. Two patent applications have been filed by Caltech and Honda Motor Co. Ltd.: US 15/228,876 (inventors: S.C.J., V.K.D., C.M.B., N.M., B.M.S., M.A.W., T.F.M., R.H.G., C.J.B., and K.O.) and US 15/844,079 (inventors: N.H.C., K.O., R.K.M., Q.X., C.J.B., S.C.J., I.M.D., and Hongjin Tan). \n\nData and materials availability: Force-field parameters and example inputs for the MD simulations performed are available for download (data S1). All other data are available in the manuscript or the supplementary materials. \n\nAll authors declare that they have no competing interests.\n\n

Supplemental Material - aat7070_Data-S1.zip

Supplemental Material - aat7070_Davis_SM.pdf

", "abstract": "Fluoride ion batteries are potential \"next-generation\" electrochemical storage devices that offer high energy density. At present, such batteries are limited to operation at high temperatures because suitable fluoride ion\u2013conducting electrolytes are known only in the solid state. We report a liquid fluoride ion\u2013conducting electrolyte with high ionic conductivity, wide operating voltage, and robust chemical stability based on dry tetraalkylammonium fluoride salts in ether solvents. Pairing this liquid electrolyte with a copper\u2013lanthanum trifluoride (Cu@LaF_3) core-shell cathode, we demonstrate reversible fluorination and defluorination reactions in a fluoride ion electrochemical cell cycled at room temperature. Fluoride ion\u2013mediated electrochemistry offers a pathway toward developing capacities beyond that of lithium ion technology.", "date": "2018-12-07", "date_type": "published", "publication": "Science", "volume": "362", "number": "6419", "publisher": "American Association for the Advancement of Science", "pagerange": "1144-1148", "id_number": "CaltechAUTHORS:20181206-162701046", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181206-162701046", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF", "grant_number": "DGE-1650116" }, { "agency": "NSF", "grant_number": "CHE-1335486" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/science.aat7070", "primary_object": { "basename": "aat7070_Data-S1.zip", "url": "https://authors.library.caltech.edu/records/yftzt-nch74/files/aat7070_Data-S1.zip" }, "related_objects": [ { "basename": "aat7070_Davis_SM.pdf", "url": "https://authors.library.caltech.edu/records/yftzt-nch74/files/aat7070_Davis_SM.pdf" } ], "pub_year": "2018", "author_list": "Davis, Victoria K.; Bates, Christopher M.; et al." }, { "id": "https://authors.library.caltech.edu/records/ca9ak-27b54", "eprint_id": 88128, "eprint_status": "archive", "datestamp": "2023-08-22 00:17:17", "lastmod": "2023-10-23 16:01:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boville-Christina-E", "name": { "family": "Boville", "given": "Christina E." }, "orcid": "0000-0002-2577-9343" }, { "id": "Scheele-Remkes-A", "name": { "family": "Scheele", "given": "Remkes A." } }, { "id": "Koch-Philipp", "name": { "family": "Koch", "given": "Philipp" } }, { "id": "Brinkmann-Chen-Sabine", "name": { "family": "Brinkmann-Chen", "given": "Sabine" }, "orcid": "0000-0002-5419-4192" }, { "id": "Buller-Andrew-R", "name": { "family": "Buller", "given": "Andrew R." }, "orcid": "0000-0002-9635-4844" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Engineered biosynthesis of \u03b2\u2010alkyl tryptophan analogs", "ispublished": "pub", "full_text_status": "public", "keywords": "Biocatalysis; tryptophan synthase; \u03b2-branched amino acid", "note": "\u00a9 2018 Wiley\u2010VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nManuscript received: July 15, 2018; Accepted manuscript online: September 14, 2018; Version of record online: October 12, 2018. \n\nWe thank Dr. David Romney, Patrick Almhjell, Dr. Christopher Prier, Nathaniel Goldberg, and Ella Watkins for helpful discussions and comments on the manuscript. We thank Dr. Jens Kaiser of the Caltech Molecular Observatory, Dr. Scott Virgil and the Center for Catalysis and Chemical Synthesis, and Dr. Mona Shahgholi and Naseem Torian from the Caltech Mass Spectrometry Laboratory. This research was funded by the Rothenberg Innovation Initiative. C.E.B. was supported by a postdoctoral fellowship from the Resnick Sustainability Institute. R.A.S. was supported by funding from the University of Groningen. \n\nConflict of interest: The enzyme variants and tryptophan analogues in this manuscript are the subject of a patent application submitted by the authors and Caltech.\n\n

Accepted Version - anie.201807998.pdf

Submitted - Boville_2018_ChemRxiv.pdf

Supplemental Material - Supplemental_Information_ChemRxiv.pdf

Supplemental Material - anie201807998-s1-c_supporting_information.pdf

", "abstract": "Noncanonical amino acids (ncAAs) with dual stereocenters at the \u03b1 and \u03b2 positions are valuable precursors to natural products and therapeutics. Despite the potential applications of such bioactive \u03b2\u2010branched ncAAs, their availability is limited due to the inefficiency of the multistep methods used to prepare them. Herein we report a stereoselective biocatalytic synthesis of \u03b2\u2010branched tryptophan analogues using an engineered variant of Pyrococcus furiosus tryptophan synthase (PfTrpB), PfTrpB^(7E6). PfTrpB^(7E6) is the first biocatalyst to synthesize bulky \u03b2\u2010branched tryptophan analogues in a single step, with demonstrated access to 27 ncAAs. The molecular basis for the efficient catalysis and broad substrate tolerance of PfTrpB^(7E6) was explored through X\u2010ray crystallography and UV/Vis spectroscopy, which revealed that a combination of active\u2010site and remote mutations increase the abundance and persistence of a key reactive intermediate. PfTrpB^(7E6) provides an operationally simple and environmentally benign platform for the preparation of \u03b2\u2010branched tryptophan building blocks.", "date": "2018-11-05", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "57", "number": "45", "publisher": "Wiley", "pagerange": "14764-14768", "id_number": "CaltechAUTHORS:20180723-111237018", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180723-111237018", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Rothenberg Innovation Initiative (RI2)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of Groningen" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201807998", "primary_object": { "basename": "anie.201807998.pdf", "url": "https://authors.library.caltech.edu/records/ca9ak-27b54/files/anie.201807998.pdf" }, "related_objects": [ { "basename": "anie201807998-s1-c_supporting_information.pdf", "url": "https://authors.library.caltech.edu/records/ca9ak-27b54/files/anie201807998-s1-c_supporting_information.pdf" }, { "basename": "Boville_2018_ChemRxiv.pdf", "url": "https://authors.library.caltech.edu/records/ca9ak-27b54/files/Boville_2018_ChemRxiv.pdf" }, { "basename": "Supplemental_Information_ChemRxiv.pdf", "url": "https://authors.library.caltech.edu/records/ca9ak-27b54/files/Supplemental_Information_ChemRxiv.pdf" } ], "pub_year": "2018", "author_list": "Boville, Christina E.; Scheele, Remkes A.; et al." }, { "id": "https://authors.library.caltech.edu/records/mza32-q4095", "eprint_id": 90144, "eprint_status": "archive", "datestamp": "2023-08-19 11:42:39", "lastmod": "2025-04-25 04:11:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ravichandran-Navaneetha-K", "name": { "family": "Ravichandran", "given": "Navaneetha K." } }, { "id": "Zhang-Hang", "name": { "family": "Zhang", "given": "Hang" } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Spectrally Resolved Specular Reflections of Thermal Phonons from Atomically Rough Surfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 the Author(s). Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. \n\n(Received 22 March 2018; revised manuscript received 13 September 2018; published 5 October 2018) \n\nhis work was supported by the National Science Foundation under Grant No. CBET CAREER 1254213. The authors thank A.\u2009A. Maznev and K.\u2009A. Nelson for fruitful discussions about the TG experiment and L. Lindsay for providing the ab initio phonon properties. N.\u2009K.\u2009R. thanks the Resnick Sustainability Institute at Caltech and the Dow Chemical Company for fellowship support. \n\nA.\u2009J.\u2009M. and N.\u2009K.\u2009R. originated the research. H.\u2009Z. and N.\u2009K.\u2009R. fabricated the silicon membrane samples. N.\u2009K.\u2009R. conducted the TG experiments and performed the BTE and the Bayesian inference calculations. N.\u2009K.\u2009R. performed the TEM imaging with help from Carol Garland at the Kavli Nanoscience Institute at Caltech. N.\u2009K.\u2009R. and A.\u2009J.\u2009M. analyzed the results and prepared the manuscript. All authors studied and commented on the manuscript. \n\nThe authors declare no competing financial interests.\n\n

Published - PhysRevX.8.041004

Supplemental Material - Supplementary_Information.pdf

", "abstract": "The reflection of waves from rough surfaces is a fundamental process that plays a role in diverse fields such as optics, acoustics, and seismology. While a quantitative understanding of the reflection process has long been established for many types of waves, the precise manner in which thermal phonons of specific wavelengths reflect from atomically rough surfaces remains unclear owing to limited control over terahertz-frequency phonon generation and detection. Knowledge of these processes is critical for many applications, however, and is particularly important for recent attempts to create novel materials by coherently interfering thermal phonons. Here, we report measurements of a key property for these efforts, the phonon-wavelength-dependent specularity parameter, which describes the probability of specular reflections of thermal phonons at a surface. Our experiments show evidence of specular surface reflections of terahertz thermal phonons in our samples around room temperature and indicate a sensitivity of these reflections to surface imperfections on the scale of just 2\u20133 atomic planes. Our work demonstrates a general route to probe the microscopic interactions of thermal phonons with surfaces that are typically inaccessible with traditional experiments.", "date": "2018-10", "date_type": "published", "publication": "Physical Review X", "volume": "8", "number": "4", "publisher": "American Physical Society", "pagerange": "Art. No. 041004", "id_number": "CaltechAUTHORS:20181005-141404733", "issn": "2160-3308", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181005-141404733", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CBET-1254213" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1103/physrevx.8.041004", "primary_object": { "basename": "Supplementary_Information.pdf", "url": "https://authors.library.caltech.edu/records/mza32-q4095/files/Supplementary_Information.pdf" }, "related_objects": [ { "basename": "PhysRevX.8.041004", "url": "https://authors.library.caltech.edu/records/mza32-q4095/files/PhysRevX.8.041004" } ], "pub_year": "2018", "author_list": "Ravichandran, Navaneetha K.; Zhang, Hang; et al." }, { "id": "https://authors.library.caltech.edu/records/xbffx-xag11", "eprint_id": 88412, "eprint_status": "archive", "datestamp": "2023-08-19 11:26:56", "lastmod": "2025-04-23 03:18:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ilic-O", "name": { "family": "Ilic", "given": "Ognjen" } }, { "id": "Went-C-M", "name": { "family": "Went", "given": "Cora M." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Nanophotonic Heterostructures for Efficient Propulsion and Radiative Cooling of Relativistic Light Sails", "ispublished": "pub", "full_text_status": "public", "keywords": "Laser propulsion, light sail, optical heterostructures, radiative cooling, Breakthrough Starshot", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: May 19, 2018; Revised: July 20, 2018; Published: July 31, 2018. \n\nThis work was supported by the Caltech Space Solar Power project (C.M.W.) and by the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center under Grant DE-SC0001293 (O.I.). C.M.W. acknowledges fellowship support from the Resnick Sustainability Institute and from an NSF Graduate Research Fellowship (Grant No. 1745301). We acknowledge helpful discussions with Zac Manchester, Mike Kelzenberg, Michelle Sherrott, Artur Davoyan, Deep Jariwala, William Whitney, Joeson Wong, and Kevin Parkin. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nl8b02035_si_001.pdf

", "abstract": "Light sails propelled by radiation pressure from high-power lasers have the potential to achieve relativistic spaceflight. In order to propel a spacecraft to relativistic speeds, an ultrathin, gram-sized light sail will need to be stably accelerated by lasers with \u223cMW/cm2 intensities operating in the near-infrared spectral range. Such a laser-driven sail requires multiband electromagnetic functionality: it must simultaneously exhibit very low absorptivity in the (Doppler-broadened) laser beam spectrum in the near-infrared and high emissivity in the mid-infrared for efficient radiative cooling. These engineering challenges present an opportunity for nanophotonic design. Here, we show that designed thin-film heterostructures could become multifunctional building-block elements of the light sail, due to their ability to achieve substantial reflectivity while maintaining low absorption in the near-infrared, significant emissivity in the mid-infrared, and a very low mass. For a light sail carrying a payload, we propose a relevant figure of merit\u2014the reflectivity adjusted area density\u2014that can capture the trade-off between sail mass and reflectivity, independent of other quantities such as the incident beam power, phased array size, or the payload mass. Furthermore, we present designs for effective thermal management via radiative cooling and compare propulsion efficiencies for several candidate materials, using a general approach that could apply to a broad range of high-power laser propulsion problems.", "date": "2018-09-12", "date_type": "published", "publication": "Nano Letters", "volume": "18", "number": "9", "publisher": "American Chemical Society", "pagerange": "5583-5589", "id_number": "CaltechAUTHORS:20180731-162143543", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180731-162143543", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Space Solar Power Project" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Space-Solar-Power-Project" } ] }, "doi": "10.1021/acs.nanolett.8b02035", "primary_object": { "basename": "nl8b02035_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xbffx-xag11/files/nl8b02035_si_001.pdf" }, "pub_year": "2018", "author_list": "Ilic, Ognjen; Went, Cora M.; et al." }, { "id": "https://authors.library.caltech.edu/records/rnjem-gkd45", "eprint_id": 88221, "eprint_status": "archive", "datestamp": "2023-08-19 11:26:23", "lastmod": "2023-10-18 21:53:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welborn-M-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Cheng-Lixue", "name": { "family": "Cheng", "given": "Lixue" }, "orcid": "0000-0002-7329-0585" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Transferability in Machine Learning for Electronic Structure via the Molecular Orbital Basis", "ispublished": "pub", "full_text_status": "public", "keywords": "machine learning, electron correlation, Gaussian processes, density-matrix functional theory", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: June 24, 2018; Published: July 24, 2018. \n\nThis work was supported by AFOSR award no. FA9550-17-1-0102. The authors additionally acknowledge support from the Resnick Sustainability Institute postdoctoral fellowship (M.W.), a Caltech Chemistry graduate fellowship (L.C.), and the Camille Dreyfus Teacher-Scholar Award (T.F.M.). \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1806.00133.pdf

Submitted - ct8b00636_si_001.pdf

", "abstract": "We present a machine learning (ML) method for predicting electronic structure correlation energies using Hartree\u2013Fock input. The total correlation energy is expressed in terms of individual and pair contributions from occupied molecular orbitals, and Gaussian process regression is used to predict these contributions from a feature set that is based on molecular orbital properties, such as Fock, Coulomb, and exchange matrix elements. With the aim of maximizing transferability across chemical systems and compactness of the feature set, we avoid the usual specification of ML features in terms of atom- or geometry-specific information, such atom/element-types, bond-types, or local molecular structure. ML predictions of MP2 and CCSD energies are presented for a range of systems, demonstrating that the method maintains accuracy while providing transferability both within and across chemical families; this includes predictions for molecules with atom-types and elements that are not included in the training set. The method holds promise both in its current form and as a proof-of-principle for the use of ML in the design of generalized density-matrix functionals.", "date": "2018-09-11", "date_type": "published", "publication": "Journal of Chemical Theory and Computation", "volume": "14", "number": "9", "publisher": "American Chemical Society", "pagerange": "4772-4779", "id_number": "CaltechAUTHORS:20180724-153741211", "issn": "1549-9618", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180724-153741211", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-17-1-0102" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Division of Chemistry and Chemical Engineering" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jctc.8b00636", "primary_object": { "basename": "1806.00133.pdf", "url": "https://authors.library.caltech.edu/records/rnjem-gkd45/files/1806.00133.pdf" }, "related_objects": [ { "basename": "ct8b00636_si_001.pdf", "url": "https://authors.library.caltech.edu/records/rnjem-gkd45/files/ct8b00636_si_001.pdf" } ], "pub_year": "2018", "author_list": "Welborn, Matthew; Cheng, Lixue; et al." }, { "id": "https://authors.library.caltech.edu/records/hfpa5-89z53", "eprint_id": 92490, "eprint_status": "archive", "datestamp": "2023-08-19 11:21:28", "lastmod": "2023-10-20 15:45:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guo-Linqi", "name": { "family": "Guo", "given": "Linqi" } }, { "id": "Liang-Chen", "name": { "family": "Liang", "given": "Chen" } }, { "id": "Zocca-A", "name": { "family": "Zocca", "given": "Alessandro" }, "orcid": "0000-0001-6585-4785" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" } } ] }, "title": "Failure Localization in Power Systems via Tree Partitions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 is held by author/owner(s). \n\nThis work has been supported by Resnick Fellowship, Linde Institute Research Award, NWO Rubicon grant 680.50.1529., NSF grants through PFI:AIR-TT award 1602119, EPCN 1619352, CNS 1545096, CCF 1637598, ECCS 1619352, CNS 1518941, CPS 154471, AitF 1637598, ARPA-E grant through award DE-AR0000699 (NODES) and GRID DATA, DTRA through grant HDTRA 1-15-1-0003 and Skoltech through collaboration agreement 1075-MRA.\n\n

Published - p57-guo.pdf

Submitted - 1803.08551.pdf

", "abstract": "Cascading failures in power systems propagate non-locally, making the control and mitigation of outages extremely hard. In this work, we use the emerging concept of the tree partition of transmission networks to provide an analytical characterization of line failure localizability in transmission systems. Our results rigorously establish the well perceived intuition in power community that failures cannot cross bridges, and reveal a finer-grained concept that encodes more precise information on failure propagations within tree-partition regions. Specifically, when a non-bridge line is tripped, the impact of this failure only propagates within well-defined components, which we refer to as cells, of the tree partition defined by the bridges. In contrast, when a bridge line is tripped, the impact of this failure propagates globally across the network, affecting the power flow on all remaining transmission lines. This characterization suggests that it is possible to improve the system robustness by temporarily switching off certain transmission lines, so as to create more, smaller components in the tree partition; thus spatially localizing line failures and making the grid less vulnerable to large-scale outages. We illustrate this approach using the IEEE 118-bus test system and demonstrate that switching off a negligible portion of transmission lines allows the impact of line failures to be significantly more localized without substantial changes in line congestion.", "date": "2018-09", "date_type": "published", "publication": "ACM SIGMETRICS Performance Evaluation Review", "volume": "46", "number": "2", "publisher": "Association for Computing Machinery (ACM)", "pagerange": "57-61", "id_number": "CaltechAUTHORS:20190128-094206311", "issn": "0163-5999", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190128-094206311", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Linde Institute of Economic and Management Science" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "680.50.1529" }, { "agency": "NSF", "grant_number": "IIP-1602119" }, { "agency": "NSF", "grant_number": "EPCN-1619352" }, { "agency": "NSF", "grant_number": "CNS-1545096" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF", "grant_number": "ECCS-1619352" }, { "agency": "NSF", "grant_number": "CNS-1518941" }, { "agency": "NSF", "grant_number": "CPS-154471" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "Advanced Research Projects Agency-Energy (ARPA-E)", "grant_number": "DE-AR0000699" }, { "agency": "Defense Threat Reduction Agency (DTRA)", "grant_number": "HDTRA 1-15-1-0003" }, { "agency": "Skoltech", "grant_number": "1075-MRA" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1145/3305218.3305240", "primary_object": { "basename": "1803.08551.pdf", "url": "https://authors.library.caltech.edu/records/hfpa5-89z53/files/1803.08551.pdf" }, "related_objects": [ { "basename": "p57-guo.pdf", "url": "https://authors.library.caltech.edu/records/hfpa5-89z53/files/p57-guo.pdf" } ], "pub_year": "2018", "author_list": "Guo, Linqi; Liang, Chen; et al." }, { "id": "https://authors.library.caltech.edu/records/hv1jj-4ex53", "eprint_id": 88429, "eprint_status": "archive", "datestamp": "2023-08-19 11:12:59", "lastmod": "2023-10-18 22:03:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Reed-Christopher-J", "name": { "family": "Reed", "given": "Christopher J." }, "orcid": "0000-0002-8774-5106" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Thermodynamics of Proton and Electron Transfer in Tetranuclear Clusters with Mn\u2013OH\u2082/OH Motifs Relevant to H\u2082O Activation by the Oxygen Evolving Complex in Photosystem II", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: June 19, 2018; Published: July 31, 2018. \n\nThis research was supported by the NIH (R01-GM102687B) and the Dreyfus Teacher-Scholar Program (T.A.). C.J.R. thanks the Resnick Sustainability Institute at Caltech for a fellowship. We thank Dr. Mike Takase and Dr. Larry Henling for assistance with crystallography, Prof. Jonas Peters for use of his laboratory's M\u00f6ssbauer spectrometer, and the Dow Next Generation Educator Fund for instrumentation. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-984247.pdf

Supplemental Material - ja8b06426_si_001.cif

Supplemental Material - ja8b06426_si_002.pdf

", "abstract": "We report the synthesis of site-differentiated heterometallic clusters with three Fe centers and a single Mn site that binds water and hydroxide in multiple cluster oxidation states. Deprotonation of Fe^(III/II)_3Mn^(II)\u2013OH\u2082 clusters leads to internal reorganization resulting in formal oxidation at Mn to generate Fe^(III/II)_3Mn^(III)\u2013OH. ^(57)Fe M\u00f6ssbauer spectroscopy reveals that oxidation state changes (three for Fe^(III/II)_3Mn\u2013OH\u2082 and four for Fe^(III/II)_3Mn\u2013OH clusters) occur exclusively at the Fe centers; the Mn center is formally Mn^(II) when water is bound and Mn^(III) when hydroxide is bound. Experimentally determined pK_a (17.4) of the [Fe^(III)\u2082Fe^(II)Mn^(II)\u2013OH\u2082] cluster and the reduction potentials of the [Fe_3Mn\u2013OH\u2082] and [Fe_3Mn\u2013OH] clusters were used to analyze the O\u2013H bond dissociation enthalpies (BDE_(O\u2013H)) for multiple cluster oxidation states. BDE_(O\u2013H) increases from 69 to 78 and 85 kcal/mol for the [Fe^(III)Fe^(II)\u2082Mn^(II)\u2013OH\u2082], [Fe^(III)\u2082Fe^(II)Mn^(II)\u2013OH\u2082], and [Fe^(III)_3Mn^(II)\u2013OH\u2082] clusters, respectively. Further insight of the proton and electron transfer thermodynamics of the [Fe_3Mn\u2013OH_x] system was obtained by constructing a potential\u2013pK_a diagram; the shift in reduction potentials of the [Fe_3Mn\u2013OH_x] clusters in the presence of different bases supports the BDE_(O\u2013H) values reported for the [Fe_3Mn\u2013OH\u2082] clusters. A lower limit of the pK_a for the hydroxide ligand of the [Fe_3Mn\u2013OH] clusters was estimated for two oxidation states. These data suggest BDE_(O\u2013H) values for the [Fe^(III)\u2082Fe^(II)Mn^(III)\u2013OH] and [Fe^(III)_3Mn^(III)\u2013OH] clusters are greater than 93 and 103 kcal/mol, which hints to the high reactivity expected of the resulting [Fe_3Mn\u2550O] in this and related multinuclear systems.", "date": "2018-08-29", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "34", "publisher": "American Chemical Society", "pagerange": "10900-10908", "id_number": "CaltechAUTHORS:20180801-091754883", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180801-091754883", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01-GM102687B" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.8b06426", "pmcid": "PMC6277146", "primary_object": { "basename": "ja8b06426_si_001.cif", "url": "https://authors.library.caltech.edu/records/hv1jj-4ex53/files/ja8b06426_si_001.cif" }, "related_objects": [ { "basename": "ja8b06426_si_002.pdf", "url": "https://authors.library.caltech.edu/records/hv1jj-4ex53/files/ja8b06426_si_002.pdf" }, { "basename": "nihms-984247.pdf", "url": "https://authors.library.caltech.edu/records/hv1jj-4ex53/files/nihms-984247.pdf" } ], "pub_year": "2018", "author_list": "Reed, Christopher J. and Agapie, Theodor" }, { "id": "https://authors.library.caltech.edu/records/778zx-rqb92", "eprint_id": 87092, "eprint_status": "archive", "datestamp": "2023-08-19 11:04:22", "lastmod": "2023-10-18 20:51:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Francis-Sonja-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Ferrer-Ivonne-M", "name": { "family": "Ferrer", "given": "Ivonne M." } }, { "id": "Torelli-Daniel-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "John-Jimmy", "name": { "family": "John", "given": "Jimmy" }, "orcid": "0000-0002-8772-8939" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Hyler-Forrest-P", "name": { "family": "Hyler", "given": "Forrest P." } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Reduction of aqueous CO_2 to 1-Propanol at MoS_2 electrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: October 20, 2017; Revised: June 12, 2018; Published: June 13, 2018. \n\nWe thank Dr. Nathan Dalleska and Dr. David VanderVelde of the Environmental Analysis Center and High Resolution NMR Facility, respectively, for many useful discussions and instrumental access and assistance. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. J.M.V. acknowledges support through an NRC Ford Foundation Postdoctoral Fellowship and UC Davis startup funds. D.A.T. acknowledges support through a Graduate Research Fellowship from the National Science Foundation. \n\nAuthor Contributions: S.A.F. and J.M.V. contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cm7b04428_si_001.pdf

", "abstract": "Reduction of carbon dioxide in aqueous electrolytes at single-crystal MoS_2 or thin-film MoS_2 electrodes yields 1-propanol as the major CO_2 reduction product, along with hydrogen from water reduction as the predominant reduction process. Lower levels of formate, ethylene glycol, and t-butanol were also produced. At an applied potential of \u22120.59 V versus a reversible hydrogen electrode, the Faradaic efficiencies for reduction of CO_2 to 1-propanol were \u223c3.5% for MoS2single crystals and \u223c1% for thin films with low edge-site densities. Reduction of CO_2 to 1-propanol is a kinetically challenging reaction that requires the overall transfer of 18 e\u2013 and 18 H+ in a process that involves the formation of 2 C\u2013C bonds. NMR analyses using ^(13)CO_2 showed the production of ^(13)C-labeled 1-propanol. In all cases, the vast majority of the Faradaic current resulted in hydrogen evolution via water reduction. H_2S was detected qualitatively when single-crystal MoS_2 electrodes were used, indicating that some desulfidization of single crystals occurred under these conditions.", "date": "2018-08-14", "date_type": "published", "publication": "Chemistry of Materials", "volume": "30", "number": "15", "publisher": "American Chemical Society", "pagerange": "4902-4908", "id_number": "CaltechAUTHORS:20180613-162202390", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180613-162202390", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Research Council" }, { "agency": "Ford Foundation" }, { "agency": "University of California, Davis" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemmater.7b04428", "primary_object": { "basename": "cm7b04428_si_001.pdf", "url": "https://authors.library.caltech.edu/records/778zx-rqb92/files/cm7b04428_si_001.pdf" }, "pub_year": "2018", "author_list": "Francis, Sonja A.; Velazquez, Jesus M.; et al." }, { "id": "https://authors.library.caltech.edu/records/49a84-qy528", "eprint_id": 87437, "eprint_status": "archive", "datestamp": "2023-08-19 10:32:52", "lastmod": "2023-10-18 21:10:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Drover-Marcus-W", "name": { "family": "Drover", "given": "Marcus W." }, "orcid": "0000-0002-2186-1040" }, { "id": "Nagata-Koichi", "name": { "family": "Nagata", "given": "Koichi" }, "orcid": "0000-0003-3767-9507" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Fusing triphenylphosphine with tetraphenylborate: introducing the 9-phosphatriptycene-10-phenylborate (PTB) anion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nReceived 30th May 2018, Accepted 22nd June 2018. First published on 22nd June 2018. \n\nThis work was supported by the NIH (GM070757), NSERC (Banting PDF award to MWD), and the Resnick Sustainability Institute at Caltech (Postdoctoral award to MWD). KN thanks the Japan Society for the Promotion of Science (JSPS) for an overseas postdoctoral fellowship. We thank Larry Henling and Dr Mike Takase for assistance with X-ray crystallography.\n\n

Accepted Version - nihms978733.pdf

Supplemental Material - c8cc04321c1_si.pdf

Supplemental Material - c8cc04321c2.cif

", "abstract": "In a fusion of two ubiquitous organometallic reagents, triphenylphosphine (PPh_3) and tetraphenylborate (BPh_4\u2212), the 9-phosphatriptycene-10-phenylborate (PTB) anion has been prepared for the first time. This borato species has been fully characterized by a suite of spectroscopic methods, and initial reactivity studies introduce it as a competent ligand for transition metals, including Co(II) and Fe(II).", "date": "2018-07-21", "date_type": "published", "publication": "Chemical Communications", "volume": "54", "number": "57", "publisher": "Royal Society of Chemistry", "pagerange": "7916-7919", "id_number": "CaltechAUTHORS:20180628-102927648", "issn": "1359-7345", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180628-102927648", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM070757" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Japan Society for the Promotion of Science (JSPS)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c8cc04321c", "pmcid": "PMC6095131", "primary_object": { "basename": "c8cc04321c2.cif", "url": "https://authors.library.caltech.edu/records/49a84-qy528/files/c8cc04321c2.cif" }, "related_objects": [ { "basename": "nihms978733.pdf", "url": "https://authors.library.caltech.edu/records/49a84-qy528/files/nihms978733.pdf" }, { "basename": "c8cc04321c1_si.pdf", "url": "https://authors.library.caltech.edu/records/49a84-qy528/files/c8cc04321c1_si.pdf" } ], "pub_year": "2018", "author_list": "Drover, Marcus W.; Nagata, Koichi; et al." }, { "id": "https://authors.library.caltech.edu/records/y1ybp-x5085", "eprint_id": 85817, "eprint_status": "archive", "datestamp": "2023-08-19 10:31:14", "lastmod": "2023-10-18 18:50:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boville-Christina-E", "name": { "family": "Boville", "given": "Christina E." }, "orcid": "0000-0002-2577-9343" }, { "id": "Romney-David-K", "name": { "family": "Romney", "given": "David K." }, "orcid": "0000-0003-0498-7597" }, { "id": "Almhjell-Patrick-J", "name": { "family": "Almhjell", "given": "Patrick J." }, "orcid": "0000-0003-0977-841X" }, { "id": "Sieben-Michaela", "name": { "family": "Sieben", "given": "Michaela" }, "orcid": "0000-0002-4412-7148" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Improved synthesis of 4-cyanotryptophan and other tryptophan analogs in aqueous solvent using variants of TrpB from Thermotoga maritima", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 25, 2018; Published: April 13, 2018. \n\nSpecial Issue: Organic and Biocompatible Transformations in\nAqueous Media. \n\nThis work was funded by the Jacobs Institute for Molecular Engineering for Medicine (JIMEM) and the Rothenberg Innovation Initiative (RI2) at Caltech. C.E.B. was supported by a postdoctoral fellowship from the Resnick Sustainability Institute, D.K.R. was supported by a Ruth Kirschstein NIH Postdoctoral Fellowship (F32GM117635), and M.S. was supported by a postdoctoral fellowship from the German Academic Exchange Service (DAAD). \n\nThe authors declare the following competing financial interest(s): The contents of this paper are the subject of a patent application submitted by Caltech, and some authors are entitled to a royalty on revenues arising from that patent. \n\nAuthor Contributions: C.E.B. and D.K.R. contributed equally to this work.\n\n

Accepted Version - nihms960701.pdf

Supplemental Material - jo8b00517_si_001.pdf

", "abstract": "The use of enzymes has become increasingly widespread in synthesis as chemists strive to reduce their reliance on organic solvents in favor of more environmentally benign aqueous media. With this in mind, we previously endeavored to engineer the tryptophan synthase \u03b2-subunit (TrpB) for production of noncanonical amino acids that had previously been synthesized through multistep routes involving water-sensitive reagents. This enzymatic platform proved effective for the synthesis of analogues of the amino acid tryptophan (Trp), which are frequently used in pharmaceutical synthesis as well as chemical biology. However, certain valuable compounds, such as the blue fluorescent amino acid 4-cyanotryptophan (4-CN-Trp), could only be made in low yield, even at elevated temperature (75 \u00b0C). Here, we describe the engineering of TrpB from Thermotoga maritima that improved synthesis of 4-CN-Trp from 24% to 78% yield. Remarkably, although the final enzyme maintains high thermostability (T50 = 93 \u00b0C), its temperature profile is shifted such that high reactivity is observed at \u223c37 \u00b0C (76% yield), creating the possibility for in vivo 4-CN-Trp production. The improvements are not specific to 4-CN-Trp; a boost in activity at lower temperature is also demonstrated for other Trp analogues.", "date": "2018-07-20", "date_type": "published", "publication": "Journal of Organic Chemistry", "volume": "83", "number": "14", "publisher": "American Chemical Society", "pagerange": "7447-7452", "id_number": "CaltechAUTHORS:20180413-091558960", "issn": "0022-3263", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180413-091558960", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Jacobs Institute for Molecular Engineering for Medicine" }, { "agency": "Rothenberg Innovation Initiative (RI2)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH Postdoctoral Fellowship", "grant_number": "F32GM117635" }, { "agency": "Deutscher Akademischer Austauschdienst (DAAD)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Jacobs-Institute-for-Molecular-Engineering-for-Medicine" } ] }, "doi": "10.1021/acs.joc.8b00517", "pmcid": "PMC6054569", "primary_object": { "basename": "nihms960701.pdf", "url": "https://authors.library.caltech.edu/records/y1ybp-x5085/files/nihms960701.pdf" }, "related_objects": [ { "basename": "jo8b00517_si_001.pdf", "url": "https://authors.library.caltech.edu/records/y1ybp-x5085/files/jo8b00517_si_001.pdf" } ], "pub_year": "2018", "author_list": "Boville, Christina E.; Romney, David K.; et al." }, { "id": "https://authors.library.caltech.edu/records/cvp59-p5e83", "eprint_id": 87681, "eprint_status": "archive", "datestamp": "2023-08-21 23:40:08", "lastmod": "2023-10-18 21:21:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brinkert-Katharina", "name": { "family": "Brinkert", "given": "Katharina" }, "orcid": "0000-0002-3593-5047" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Akay-\u00d6mer", "name": { "family": "Akay", "given": "\u00d6mer" } }, { "id": "Liedtke-Janine", "name": { "family": "Liedtke", "given": "Janine" }, "orcid": "0000-0003-2680-4130" }, { "id": "Giersig-Michael", "name": { "family": "Giersig", "given": "Michael" } }, { "id": "Fountaine-Katherine-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Efficient solar hydrogen generation in microgravity environment", "ispublished": "pub", "full_text_status": "public", "keywords": "Chemical engineering; Electrocatalysis; Nanoscale materials; Photocatalysis; Solar fuels", "note": "\u00a9 The Author(s) 2018. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 07 March 2018; Accepted 23 May 2018; Published 10 July 2018. \n\nK.B. acknowledges funding from the fellowship programme of the German National Academy of Sciences Leopoldina, grant LPDS 2016-06 and the European Space Agency. Furthermore, she would like to thank Dr. Leopold Summerer, the Advanced Concepts Team, Alan Dowson, Dr. Jack van Loon, Dr. Gabor Milassin, Marcel van Slogteren and Dr. Robert Lindner (ESTEC), Robbert-Jan Noordam (Notese) and Prof. Harry B. Gray (Caltech) for their great support. M.H.R. is grateful for generous support from Prof. Nathan S. Lewis (Caltech). K.B. and M.H.R. acknowledge support from the Beckman Institute of the California Institute of Technology and the Molecular Materials Research Center. M.G. acknowledges funding from the Guangdong Innovative and Entrepreneurial Team Program titled 'Plasmonic Nanomaterials and Quantum Dots for Light Management in Optoelectronic Devices' (No. 2016ZT06C517). Furthermore, the author team greatly acknowledges the effort and support from the ZARM Team with Dr. Thorben K\u00f6nemann and Dr. Martin Castillo at the Bremen Drop Tower. It is also thankful for enlightening discussions with Prof. Yasuhiro Fukunaka (Waseda University), Prof. Hisayoshi Matsushima (Hokkaido University) and Dr. Slobodan Mitrovic (Lam Research). The team would also like to thank Dr. Eser Metin Akinoglu from the International Academy of Optoelectronics, Zhaoqing, for his help with the SEM characterization of the samples and Dr. Axel Knop-Gericke (Fritz Haber Institute of the Max Planck Society) for his generous help with XPS measurements. \n\nAuthor Contributions: K.B., M.H.R., J.L. and H.-J.L. planned and carried out the terrestrial experiments and the experiments at the Bremen Drop Tower. \u00d6.A., K.B. and J.L. prepared the nanostructured photoelectrodes under the supervision of M.G. and H.-J.L. K.T.F. carried out the theoretical calculations and simulations. K.B., H.-J.L and K.T.F. wrote the manuscript which is approved by all authors. \n\nThe authors declare no competing interests. \n\nData availability: All relevant data are available from the authors upon request.\n\n

Published - s41467-018-04844-y.pdf

Supplemental Material - 41467_2018_4844_MOESM1_ESM.pdf

Supplemental Material - 41467_2018_4844_MOESM2_ESM.pdf

", "abstract": "Long-term space missions require extra-terrestrial production of storable, renewable energy. Hydrogen is ascribed a crucial role for transportation, electrical power and oxygen generation. We demonstrate in a series of drop tower experiments that efficient direct hydrogen production can be realized photoelectrochemically in microgravity environment, providing an alternative route to existing life support technologies for space travel. The photoelectrochemical cell consists of an integrated catalyst-functionalized semiconductor system that generates hydrogen with current densities >15\u2009mA/cm^2 in the absence of buoyancy. Conditions are described adverting the resulting formation of ion transport blocking froth layers on the photoelectrodes. The current limiting factors were overcome by controlling the micro- and nanotopography of the Rh electrocatalyst using shadow nanosphere lithography. The behaviour of the applied system in terrestrial and microgravity environment is simulated using a kinetic transport model. Differences observed for varied catalyst topography are elucidated, enabling future photoelectrode designs for use in reduced gravity environments.", "date": "2018-07-10", "date_type": "published", "publication": "Nature Communications", "volume": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2527", "id_number": "CaltechAUTHORS:20180710-080707049", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180710-080707049", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Akademie der Naturforscher Leopoldina", "grant_number": "LPDS 2016-06" }, { "agency": "European Space Agency (ESA)" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Guangdong Innovative and Entrepreneurial Team Program", "grant_number": "2016ZT06C517" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-018-04844-y", "pmcid": "PMC6039473", "primary_object": { "basename": "41467_2018_4844_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cvp59-p5e83/files/41467_2018_4844_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2018_4844_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cvp59-p5e83/files/41467_2018_4844_MOESM2_ESM.pdf" }, { "basename": "s41467-018-04844-y.pdf", "url": "https://authors.library.caltech.edu/records/cvp59-p5e83/files/s41467-018-04844-y.pdf" } ], "pub_year": "2018", "author_list": "Brinkert, Katharina; Richter, Matthias H.; et al." }, { "id": "https://authors.library.caltech.edu/records/4r9bv-j6q69", "eprint_id": 87418, "eprint_status": "archive", "datestamp": "2023-08-19 09:55:12", "lastmod": "2023-10-18 21:09:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shan-Yuli", "name": { "family": "Shan", "given": "Yuli" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Hubacek-K", "name": { "family": "Hubacek", "given": "Klaus" }, "orcid": "0000-0003-2561-6090" }, { "id": "Zheng-Bo", "name": { "family": "Zheng", "given": "Bo" }, "orcid": "0000-0001-8344-3445" }, { "id": "Davis-S-J", "name": { "family": "Davis", "given": "Steven J." }, "orcid": "0000-0002-9338-0844" }, { "id": "Jia-Lichao", "name": { "family": "Jia", "given": "Lichao" } }, { "id": "Liu-Jianghua", "name": { "family": "Liu", "given": "Jianghua" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Fromer-N-A", "name": { "family": "Fromer", "given": "Neil" } }, { "id": "Mi-Zhifu", "name": { "family": "Mi", "given": "Zhifu" }, "orcid": "0000-0001-8106-0694" }, { "id": "Meng-Jing", "name": { "family": "Meng", "given": "Jing" }, "orcid": "0000-0002-9069-8988" }, { "id": "Deng-Xiangzheng", "name": { "family": "Deng", "given": "Xiangzheng" } }, { "id": "Li-Yuan", "name": { "family": "Li", "given": "Yuan" } }, { "id": "Lin-Jintai", "name": { "family": "Lin", "given": "Jintai" } }, { "id": "Schroeder-H", "name": { "family": "Schroeder", "given": "Heike" } }, { "id": "Weisz-H", "name": { "family": "Weisz", "given": "Helga" }, "orcid": "0000-0001-8208-5199" }, { "id": "Schelinhuber-H-J", "name": { "family": "Schelinhuber", "given": "Hans Joachim" } } ] }, "title": "City-level climate change mitigation in China", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY). This is an open-access article distributed under the terms of the Creative Commons Attribution license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. \n\nSubmitted 25 September 2017. Accepted 21 May 2018. Published 27 June 2018. \n\nThis work was supported by the National Key R&D Program of China (2016YFA0602604 and 2016YFA0602500), the Natural Science Foundation of China (71533005, 51502103, 71503156, 41629501, and 41501605), the Social Science Foundation of China (15CJY058), the UK Economic and Social Research Council (ES/L016028/1), the Natural Environment Research Council (NE/N00714X/1), a British Academy Grant (AF150310), the Philip Leverhulme Prize, N.F. and Z.L. thank the Resnick Sustainability Institute at Caltech. \n\nAuthor contributions: Y.S. and D.G. designed the research. Y.S., Z.L., Z.M., J.M., Y.L., and H.S. performed the research. Y.S. and J. Liu prepared data. Y.S. and S.J.D. wrote the paper with inputs from K.H., B.Z., J. Lin, X.D., L.J., N.F., H.W., and H.J.S. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are uploaded to CEADs (www.ceads.net) for free download. Additional data related to this paper may be requested from the authors. \n\nThe authors declare that they have no competing interests.\n\n

Published - eaaq0390.full.pdf

Supplemental Material - aaq0390_SM.pdf

Supplemental Material - aaq0390_TablesS1_to_S5.xlsx

", "abstract": "As national efforts to reduce CO_2 emissions intensify, policy-makers need increasingly specific, subnational information about the sources of CO_2 and the potential reductions and economic implications of different possible policies. This is particularly true in China, a large and economically diverse country that has rapidly industrialized and urbanized and that has pledged under the Paris Agreement that its emissions will peak by 2030. We present new, city-level estimates of CO_2 emissions for 182 Chinese cities, decomposed into 17 different fossil fuels, 46 socioeconomic sectors, and 7 industrial processes. We find that more affluent cities have systematically lower emissions per unit of gross domestic product (GDP), supported by imports from less affluent, industrial cities located nearby. In turn, clusters of industrial cities are supported by nearby centers of coal or oil extraction. Whereas policies directly targeting manufacturing and electric power infrastructure would drastically undermine the GDP of industrial cities, consumption-based policies might allow emission reductions to be subsidized by those with greater ability to pay. In particular, sector-based analysis of each city suggests that technological improvements could be a practical and effective means of reducing emissions while maintaining growth and the current economic structure and energy system. We explore city-level emission reductions under three scenarios of technological progress to show that substantial reductions (up to 31%) are possible by updating a disproportionately small fraction of existing infrastructure.", "date": "2018-06-27", "date_type": "published", "publication": "Science Advances", "volume": "4", "number": "6", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eaaq0390", "id_number": "CaltechAUTHORS:20180627-152741323", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180627-152741323", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Basic Research Program of China", "grant_number": "2016YFA0602604" }, { "agency": "National Key Basic Research Program of China", "grant_number": "2016YFA0602500" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71533005" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51502103" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71503156" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41629501" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41501605" }, { "agency": "Social Science Foundation of China", "grant_number": "15CJY058" }, { "agency": "Economic and Social Research Council (ESRC)", "grant_number": "ES/L016028/1" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/N00714X/1" }, { "agency": "British Academy", "grant_number": "AF150310" }, { "agency": "Philip Leverhulme Prize" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.aaq0390", "primary_object": { "basename": "aaq0390_SM.pdf", "url": "https://authors.library.caltech.edu/records/4r9bv-j6q69/files/aaq0390_SM.pdf" }, "related_objects": [ { "basename": "aaq0390_TablesS1_to_S5.xlsx", "url": "https://authors.library.caltech.edu/records/4r9bv-j6q69/files/aaq0390_TablesS1_to_S5.xlsx" }, { "basename": "eaaq0390.full.pdf", "url": "https://authors.library.caltech.edu/records/4r9bv-j6q69/files/eaaq0390.full.pdf" } ], "pub_year": "2018", "author_list": "Shan, Yuli; Guan, Dabo; et al." }, { "id": "https://authors.library.caltech.edu/records/pz95m-t6c86", "eprint_id": 87301, "eprint_status": "archive", "datestamp": "2023-08-19 09:52:50", "lastmod": "2023-10-18 21:02:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nesti-T", "name": { "family": "Nesti", "given": "Tommaso" } }, { "id": "Zocca-A", "name": { "family": "Zocca", "given": "Alessandro" }, "orcid": "0000-0001-6585-4785" }, { "id": "Zwart-B", "name": { "family": "Zwart", "given": "Bert" } } ] }, "title": "Emergent Failures and Cascades in Power Grids: A Statistical Physics Perspective", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Physical Society. \n\nReceived 25 July 2017; revised manuscript received 4 April 2018; published 21 June 2018. \n\nWe thank the referees for many useful comments, in particular, for suggesting SciGRID. NWO Vici 639.033.413 and NWO Rubicon 680.50.1529 grants provided financial support. A.\u2009Z. acknowledges the support of Resnick Sustainability Institute at Caltech.\n\n

Published - PhysRevLett.120.258301.pdf

Accepted Version - 1709.10166.pdf

Supplemental Material - supplementarymaterial_2018_cameraready.pdf

", "abstract": "We model power grids transporting electricity generated by intermittent renewable sources as complex networks, where line failures can emerge indirectly by noisy power input at the nodes. By combining concepts from statistical physics and the physics of power flows and taking weather correlations into account, we rank line failures according to their likelihood and establish the most likely way such failures occur and propagate. Our insights are mathematically rigorous in a small-noise limit and are validated with data from the German transmission grid.", "date": "2018-06-22", "date_type": "published", "publication": "Physical Review Letters", "volume": "120", "number": "25", "publisher": "American Physical Society", "pagerange": "Art. No. 258301", "id_number": "CaltechAUTHORS:20180621-100145040", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180621-100145040", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "639.033.413" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)", "grant_number": "680.50.1529" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevLett.120.258301", "primary_object": { "basename": "1709.10166.pdf", "url": "https://authors.library.caltech.edu/records/pz95m-t6c86/files/1709.10166.pdf" }, "related_objects": [ { "basename": "PhysRevLett.120.258301.pdf", "url": "https://authors.library.caltech.edu/records/pz95m-t6c86/files/PhysRevLett.120.258301.pdf" }, { "basename": "supplementarymaterial_2018_cameraready.pdf", "url": "https://authors.library.caltech.edu/records/pz95m-t6c86/files/supplementarymaterial_2018_cameraready.pdf" } ], "pub_year": "2018", "author_list": "Nesti, Tommaso; Zocca, Alessandro; et al." }, { "id": "https://authors.library.caltech.edu/records/9bhpv-g5s39", "eprint_id": 86845, "eprint_status": "archive", "datestamp": "2023-08-19 09:50:22", "lastmod": "2023-10-18 20:38:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Webb-M-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Yamamoto-Umi", "name": { "family": "Yamamoto", "given": "Umi" } }, { "id": "Savoie-B-M", "name": { "family": "Savoie", "given": "Brett M." }, "orcid": "0000-0002-7039-4039" }, { "id": "Wang-Zhen-Gang", "name": { "family": "Wang", "given": "Zhen-Gang" }, "orcid": "0000-0002-3361-6114" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Globally Suppressed Dynamics in Ion-Doped Polymers", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: March 30, 2018; Accepted: June 4, 2018; Published: June 6, 2018. \n\nThis research was supported by the National Science Foundation under DMREF Award Number NSF-CHE-1335486. M.A.W. also acknowledges support from the Resnick Sustainability Institute. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - mz8b00237_si_001.pdf

", "abstract": "We investigate how ion\u2013polymer complexation suppresses molecular motion in conventional polymer electrolytes using molecular dynamics (MD) simulations of lithium hexafluorophosphate in poly(ethylene oxide) and a modified Rouse model. The employed model utilizes an inhomogeneous friction distribution to describe ion\u2013polymer interactions and provides an effective way to examine how ion\u2013polymer interactions affect polymer motion. By characterizing the subdiffusive Li^+ transport and polymer relaxation times at several salt concentrations, we observe that increases in local friction due to ion-polymer complexation are significantly smaller than previously assumed. We find that a Rouse-based model that only considers local increases in friction cannot simultaneously capture the magnitude of increased polymer relaxation times and the apparent power-law exponent for Li^+ subdiffusion observed in MD simulations. This incompatibility is reconciled by augmenting the modified Rouse model with a term that increases the global friction with the square of the salt concentration; this significantly improves the agreement between the model and MD, indicating the importance of ion\u2013ion interactions and distributions on ion/polymer mobility.", "date": "2018-06-19", "date_type": "published", "publication": "ACS Macro Letters", "volume": "7", "number": "6", "publisher": "American Chemical Society", "pagerange": "734-738", "id_number": "CaltechAUTHORS:20180606-124846827", "issn": "2161-1653", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180606-124846827", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1335486" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsmacrolett.8b00237", "primary_object": { "basename": "mz8b00237_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9bhpv-g5s39/files/mz8b00237_si_001.pdf" }, "pub_year": "2018", "author_list": "Webb, Michael A.; Yamamoto, Umi; et al." }, { "id": "https://authors.library.caltech.edu/records/tpre5-hge40", "eprint_id": 86732, "eprint_status": "archive", "datestamp": "2023-08-19 09:44:38", "lastmod": "2023-10-18 19:56:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Landers-A-T", "name": { "family": "Landers", "given": "Alan T." } }, { "id": "Fields-M", "name": { "family": "Fields", "given": "Meredith" } }, { "id": "Torelli-D-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Xiao-Jianping", "name": { "family": "Xiao", "given": "Jianping" }, "orcid": "0000-0003-1779-6140" }, { "id": "Hellstern-T-R", "name": { "family": "Hellstern", "given": "Thomas R." } }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Tsai-Charlie", "name": { "family": "Tsai", "given": "Charlie" } }, { "id": "Kibsgaard-J", "name": { "family": "Kibsgaard", "given": "Jakob" }, "orcid": "0000-0002-9219-816X" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" }, { "id": "Hahn-C", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "The Predominance of Hydrogen Evolution on Transition Metal Sulfides and Phosphides under CO_2 Reduction Conditions: An Experimental and Theoretical Study", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 9, 2018; Accepted: April 20, 2018; Publication Date (Web): May 31, 2018. \n\nThis material is based, in part, on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy, under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy (under Contract No. DE-AC02-05CH11231). Part of this work was performed at the Stanford Nano Shared Facilities (SNSF) and the Stanford Nanofabrication Facility (SNF), supported by the National Science Foundation under Award ECCS-1542152. We also acknowledge assistance from the Stanford NMR Facility. M.F. and D.A.T. acknowledge a graduate fellowship through the National Science Foundation. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a postdoctoral fellowship. The authors also thank J. Chance Crompton for assistance in synthesizing the nanoparticle electrocatalysts. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nz8b00237_si_001.pdf

", "abstract": "A combination of experiment and theory has been used to understand the relationship between the hydrogen evolution reaction (HER) and CO_2 reduction (CO_2R) on transition metal phosphide and transition metal sulfide catalysts. Although multifunctional active sites in these materials could potentially improve their CO_2R activity relative to pure transition metal electrocatalysts, under aqueous testing conditions, these materials showed a high selectivity for the HER relative to CO_2R. Computational results supported these findings, indicating that a limitation of the metal phosphide catalysts is that the HER is favored thermodynamically over CO_2R. On Ni-MoS_2, a limitation is the kinetic barrier for the proton\u2013electron transfer to *CO. These theoretical and experimental results demonstrate that selective CO_2R requires electrocatalysts that possess both favorable thermodynamic pathways and surmountable kinetic barriers.", "date": "2018-06-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "6", "publisher": "American Chemical Society", "pagerange": "1450-1457", "id_number": "CaltechAUTHORS:20180601-080239556", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180601-080239556", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ECCS-1542152" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.8b00237", "primary_object": { "basename": "nz8b00237_si_001.pdf", "url": "https://authors.library.caltech.edu/records/tpre5-hge40/files/nz8b00237_si_001.pdf" }, "pub_year": "2018", "author_list": "Landers, Alan T.; Fields, Meredith; et al." }, { "id": "https://authors.library.caltech.edu/records/ht5fh-jha05", "eprint_id": 87400, "eprint_status": "archive", "datestamp": "2023-08-19 09:30:25", "lastmod": "2023-10-18 21:08:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McKeon-B-J", "name": { "family": "McKeon", "given": "Beverley J." }, "orcid": "0000-0003-4220-1583" }, { "id": "Jacobi-I", "name": { "family": "Jacobi", "given": "Ian" } }, { "id": "Duvvuri-S", "name": { "family": "Duvvuri", "given": "Subrahmanyam" }, "orcid": "0000-0001-8082-1658" } ] }, "title": "Dynamic Roughness for Manipulation and Control of Turbulent Boundary Layers: An Overview", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2018 by the authors. Published by the American Institute of Aeronautics and Astronautics, Inc., with permission. \n\nReceived 28 September 2017; revision received 5 January 2018; accepted for publication 15 January 2018; published online 5 March 2018. \n\nThe authors gratefully acknowledge the support of the U.S. Air Force Office of Scientific Research (AFOSR) for the dynamic roughness work at the California Institute of Technology through AFOSR grant numbers FA9550-08-1-0049, FA9550-09-1-0701, FA9550-12-1-0469, and FA9550-16-1-0361. Subrahmanyam Duvvuri is grateful for the past support of a graduate fellowship from the Resnick Institute at the California Institute of Technology.", "abstract": "The use of dynamic roughness or small, oscillating, wall roughness elements to manipulate the structure of turbulent boundary layers is reviewed with a view to imposing true active control techniques. Linear and nonlinear responses to simple oscillations are detailed, such that the modifications of the overall structure of the turbulence and interactions between scales can be inferred. Although the work considered here uses mechanical actuation, the approach is considered sufficiently general to be implemented by a range of techniques, including engineered microelectromechanical system devices and metamaterial actuators.", "date": "2018-06", "date_type": "published", "publication": "AIAA Journal", "volume": "56", "number": "6", "publisher": "AIAA", "pagerange": "2178-2193", "id_number": "CaltechAUTHORS:20180627-120113196", "issn": "0001-1452", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180627-120113196", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-08-1-0049" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-09-1-0701" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0469" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0361" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "GALCIT" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.2514/1.J056764", "pub_year": "2018", "author_list": "McKeon, Beverley J.; Jacobi, Ian; et al." }, { "id": "https://authors.library.caltech.edu/records/etbm7-cz134", "eprint_id": 86213, "eprint_status": "archive", "datestamp": "2023-08-19 09:22:28", "lastmod": "2023-10-18 19:22:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roberts-E-J", "name": { "family": "Roberts", "given": "Emily J." } }, { "id": "Read-C-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Brutchey-R-L", "name": { "family": "Brutchey", "given": "Richard L." }, "orcid": "0000-0002-7781-5596" } ] }, "title": "Phase Directing Ability of an Ionic Liquid Solvent for the Synthesis of HER-Active Ni_2P Nanocrystals", "ispublished": "pub", "full_text_status": "public", "keywords": "ionic liquid, nickel phosphide, nanocrystal, electrocatalyst, hydrogen evolution reaction", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 13, 2018; Accepted: May 3, 2018; Published: May 3, 2018. \n\nR.L.B. acknowledges NSF for supporting the synthetic chemistry under CMMI-1728649. N.S.L. acknowledges NSF for supporting the electrochemical characterization work under the NSF CCI Solar Fuels Program CHE-1305124. C.G.R. acknowledges the Resnick Sustainability Institute for a postdoctral fellowship. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ae8b00213_si_001.pdf

", "abstract": "An ionic liquid (IL) solvent was used to synthesize small, phase-pure nickel phosphide (Ni_2P) nanocrystals. In contrast, under analogous reaction conditions, substitution of the IL for the common high-boiling organic solvent 1-octadecene (ODE) results in phase-impure nanocrystals. The 5 nm Ni_2P nanocrystals prepared in IL were electrocatalytically active toward the hydrogen evolution reaction. The synthesis in IL was also extended to alloyed Ni_(2\u2013x)Co_xP nanocrystals, where 0.5 \u2264 x \u2264 1.5.", "date": "2018-05-29", "date_type": "published", "publication": "ACS Applied Energy Materials", "volume": "1", "number": "5", "publisher": "American Chemical Society", "pagerange": "1823-1827", "id_number": "CaltechAUTHORS:20180503-144511877", "issn": "2574-0962", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180503-144511877", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CMMI-1728649" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsaem.8b00213", "primary_object": { "basename": "ae8b00213_si_001.pdf", "url": "https://authors.library.caltech.edu/records/etbm7-cz134/files/ae8b00213_si_001.pdf" }, "pub_year": "2018", "author_list": "Roberts, Emily J.; Read, Carlos G.; et al." }, { "id": "https://authors.library.caltech.edu/records/mvtf9-ns803", "eprint_id": 85963, "eprint_status": "archive", "datestamp": "2023-08-19 09:16:11", "lastmod": "2023-10-18 19:08:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chalkley-Matthew-J", "name": { "family": "Chalkley", "given": "Matthew J." }, "orcid": "0000-0002-0484-7335" }, { "id": "Del-Castillo-Trevor-J", "name": { "family": "Del Castillo", "given": "Trevor J." } }, { "id": "Matson-Benjamin-D", "name": { "family": "Matson", "given": "Benjamin D." }, "orcid": "0000-0001-5733-0893" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Fe-Mediated Nitrogen Fixation with a Metallocene Mediator: Exploring pK_a Effects and Demonstrating Electrocatalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 28, 2018\nPublished: April 18, 2018\nPublication Date (Web): April 18, 2018.\n\nThis work was supported by the NIH (GM-075757) and the\nResnick Sustainability Institute at Caltech. MJC, TJDC, and\nBDM are grateful for NSF Graduate Research Fellowships and\nMJC acknowledges a Caltech Environment Microbial Interactions\n(CEMI) Fellowship. This work made use of the Extreme\nScience and Engineering Discovery Environment (XSEDE),\nwhich is supported by the NSF Grant ACI-1053575. We also\nthank Pakpoom Buabthong for technical assistance with XPS\nmeasurements.\n\n

Accepted Version - nihms974382.pdf

Supplemental Material - ja8b02335_si_001.pdf

Supplemental Material - ja8b02335_si_002.mol

", "abstract": "Substrate selectivity in reductive multi-electron/proton catalysis with small molecules such as N_2, CO_2, and O_2 is a major challenge for catalyst design, especially where the competing hydrogen evolution reaction (HER) is thermodynamically and kinetically competent. In this study, we investigate how the selectivity of a tris(phosphine)borane iron(I) catalyst, P_3^BFe^+, for catalyzing the nitrogen reduction reaction (N_2RR, N_2-to-NH_3 conversion) versus HER changes as a function of acid pK_a. We find that there is a strong correlation between pKa and N_2RR efficiency. Stoichiometric studies indicate that the anilinium triflate acids employed are only compatible with the formation of early stage intermediates of N_2 reduction (e.g., Fe(NNH) or Fe(NNH_2)) in the presence of the metallocene reductant Cp*_2Co. This suggests that the interaction of acid and reductant is playing a critical role in N\u2013H bond forming reactions. DFT studies identify a protonated metallocene species as a strong PCET donor and suggest that it should be capable of forming the early stage N\u2013H bonds critical for N_2RR. Furthermore, DFT studies also suggest that the observed pK_a effect on N_2RR efficiency is attributable to the rate and thermodynamics, of Cp*_2Co protonation by the different anilinium acids. Inclusion of Cp*_2Co^+ as a co-catalyst in controlled potential electrolysis experiments leads to improved yields of NH_3. The data presented provide what is to our knowledge the first unambiguous demonstration of electrocatalytic nitrogen fixation by a molecular catalyst (up to 6.7 equiv NH_3 per Fe at \u22122.1 V vs Fc^(+/0)).", "date": "2018-05-16", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "19", "publisher": "American Chemical Society", "pagerange": "6122-6129", "id_number": "CaltechAUTHORS:20180418-164723702", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180418-164723702", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM-075757" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Caltech Center for Environmental Microbial Interactions (CEMI)" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Caltech-Center-for-Environmental-Microbial-Interactions-(CEMI)" } ] }, "doi": "10.1021/jacs.8b02335", "pmcid": "PMC6071328", "primary_object": { "basename": "nihms974382.pdf", "url": "https://authors.library.caltech.edu/records/mvtf9-ns803/files/nihms974382.pdf" }, "related_objects": [ { "basename": "ja8b02335_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mvtf9-ns803/files/ja8b02335_si_001.pdf" }, { "basename": "ja8b02335_si_002.mol", "url": "https://authors.library.caltech.edu/records/mvtf9-ns803/files/ja8b02335_si_002.mol" } ], "pub_year": "2018", "author_list": "Chalkley, Matthew J.; Del Castillo, Trevor J.; et al." }, { "id": "https://authors.library.caltech.edu/records/t6ep1-s6h83", "eprint_id": 85874, "eprint_status": "archive", "datestamp": "2023-08-19 08:52:54", "lastmod": "2023-10-18 19:03:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chu-Crystal-K", "name": { "family": "Chu", "given": "Crystal K." }, "orcid": "0000-0002-7783-2564" }, { "id": "Lin-Tzu-Pin", "name": { "family": "Lin", "given": "Tzu-Pin" }, "orcid": "0000-0001-7041-7213" }, { "id": "Shao-Huiling", "name": { "family": "Shao", "given": "Huiling" } }, { "id": "Liberman-Martin-A-L", "name": { "family": "Liberman-Martin", "given": "Allegra L." }, "orcid": "0000-0002-8447-905X" }, { "id": "Liu-Peng-Chemistry", "name": { "family": "Liu", "given": "Peng" }, "orcid": "0000-0002-8188-632X" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Disentangling Ligand Effects on Metathesis Catalyst Activity: Experimental and Computational Studies of Ruthenium\u2013Aminophosphine Complexes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 27, 2018; Published: April 5, 2018. \n\nWe thank Dr. David VanderVelde for assistance with NMR spectroscopic experiments and Lawrence Henling for assistance with X-ray crystallography. Dr. Mona Shahgholi and Naseem Torian are acknowledged for assistance with mass spectrometry. Dr. Adam Johns is thanked for helpful discussions regarding aminophosphine and catalyst synthesis. Dr. Choon Woo Lee, Dr. Keary Engle, Dr. William Wolf, Lennon Luo, and Tonia Ahmed are acknowledged for helpful discussions of kinetics of olefin metathesis. Materia, Inc. is thanked for donation of catalyst G2. We acknowledge ONR (N00014-13-1-0895 and N00014-14-1-0650) and ARPA-E (DE-AR0000683) for financial support, and the Resnick Sustainability Institute for a fellowship to A.L.L.-M. DFT calculations were performed at the Center for Research Computing at the University of Pittsburgh and the Extreme Science and Engineering Discovery Environment (XSEDE) supported by the National Science Foundation. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja8b02324_si_001.pdf

Supplemental Material - ja8b02324_si_002.cif

Supplemental Material - ja8b02324_si_003.cif

Supplemental Material - ja8b02324_si_004.cif

Supplemental Material - ja8b02324_si_005.cif

", "abstract": "Second-generation ruthenium olefin metathesis catalysts bearing aminophosphine ligands were investigated with systematic variation of the ligand structure. The rates of phosphine dissociation (k_1; initiation rate) and relative phosphine reassociation (k_(\u20131)) were determined for two series of catalysts bearing cyclohexyl(morpholino)phosphine and cyclohexyl(piperidino)phosphine ligands. In both cases, incorporating P\u2013N bonds into the architecture of the dissociating phosphine accelerates catalyst initiation relative to the parent [Ru]\u2013PCy_3 complex; however, this effect is muted for the tris(amino)phosphine-ligated complexes, which exhibit higher ligand binding constants in comparison to those with phosphines containing one or two cyclohexyl substituents. These results, along with X-ray crystallographic data and DFT calculations, were used to understand the influence of ligand structure on catalyst activity. Especially noteworthy is the application of phosphines containing incongruent substituents (PR_1R\u2032_2); detailed analyses of factors affecting ligand dissociation, including steric effects, inductive effects, and ligand conformation, are presented. Computational studies of the reaction coordinate for ligand dissociation reveal that ligand conformational changes contribute to the rapid dissociation for the fastest-initiating catalyst of these series, which bears a cyclohexyl-bis(morpholino)phosphine ligand. Furthermore, the effect of amine incorporation was examined in the context of ring-opening metathesis polymerization, and reaction rates were found to correlate well with catalyst initiation rates. The combined experimental and computational studies presented in this report reveal important considerations for designing efficient ruthenium olefin metathesis catalysts.", "date": "2018-04-25", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "16", "publisher": "American Chemical Society", "pagerange": "5634-5643", "id_number": "CaltechAUTHORS:20180416-092159771", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180416-092159771", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-13-1-0895" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-14-1-0650" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000683" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.8b02324", "primary_object": { "basename": "ja8b02324_si_001.pdf", "url": "https://authors.library.caltech.edu/records/t6ep1-s6h83/files/ja8b02324_si_001.pdf" }, "related_objects": [ { "basename": "ja8b02324_si_002.cif", "url": "https://authors.library.caltech.edu/records/t6ep1-s6h83/files/ja8b02324_si_002.cif" }, { "basename": "ja8b02324_si_003.cif", "url": "https://authors.library.caltech.edu/records/t6ep1-s6h83/files/ja8b02324_si_003.cif" }, { "basename": "ja8b02324_si_004.cif", "url": "https://authors.library.caltech.edu/records/t6ep1-s6h83/files/ja8b02324_si_004.cif" }, { "basename": "ja8b02324_si_005.cif", "url": "https://authors.library.caltech.edu/records/t6ep1-s6h83/files/ja8b02324_si_005.cif" } ], "pub_year": "2018", "author_list": "Chu, Crystal K.; Lin, Tzu-Pin; et al." }, { "id": "https://authors.library.caltech.edu/records/3rqhh-jkr64", "eprint_id": 84674, "eprint_status": "archive", "datestamp": "2023-08-21 23:12:08", "lastmod": "2023-10-18 16:32:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Jiaoyue", "name": { "family": "Wang", "given": "Jiaoyue" } }, { "id": "Xi-Fengming", "name": { "family": "Xi", "given": "Fengming" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Bing-Longfei", "name": { "family": "Bing", "given": "Longfei" } }, { "id": "Alsaedi-A", "name": { "family": "Alsaedi", "given": "Ahmad" } }, { "id": "Hayat-T", "name": { "family": "Hayat", "given": "Tasawar" } }, { "id": "Ahmad-B", "name": { "family": "Ahmad", "given": "Bashir" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } } ] }, "title": "The spatiotemporal features of Greenhouse Gases Emissions from Biomass Burning in China from 2000-2012", "ispublished": "pub", "full_text_status": "public", "keywords": "Greenhouse gases emission; Biomass burning; Biofuel; Open burning", "note": "\u00a9 2018 Elsevier Ltd. \n\nAvailable online 3 February 2018.", "abstract": "Greenhouse gases emissions from biomass burning have been given a little attention, especially the spatiotemporal features of biomass burning sources and greenhouse gases emissions have not been comprehensively uncovered. This research undertook IPCC bottom-up inventory guideline to estimate Chinese greenhouse gases emissions from biomass burning and applied geographical information system to reveal biomass burning emissions spatiotemporal features. The purposes were to quantify greenhouse gases emissions from various biomass burning sources and to uncover the spatial and temporal emissions features so to deliver future policy implications in China. The results showed that the average annual biomass burning emissions in China from 2000-2012 were 880.66 Mt for CO_2, 96.59 Mt CO_2-eq for CH_4, and 16.81 Mt CO_2-eq for N_2O. The spatial pattern of biomass greenhouse gases emissions showed about 50 % of national emission were in the east and south-central regions. The majority of biomass burning emissions were from firewood and crop residues, which accounted for more than 90 % of national biomass burning emissions. All types of biomass burning emissions exhibited similar temporal trends from 2000-2012, with strong inter-annual variability and fluctuant increase. The large grassland and forest fires induced the significant greenhouse gases emissions peaks in the years of 2001, 2003 and 2006. We found that biofuel burning, with low combustion efficiency, is the major emission source. Open burning of biomass was widespread in China, and east and south-central regions were the major distribution of biomass burning greenhouse gases emission. Optimized design for improving the efficiency of biomass utilization and making emission control policy combination with its spatiotemporal features will be the effective way to reduce the biomass burning emissions.", "date": "2018-04-20", "date_type": "published", "publication": "Journal of Cleaner Production", "volume": "181", "publisher": "Elsevier", "pagerange": "801-808", "id_number": "CaltechAUTHORS:20180205-100509462", "issn": "0959-6526", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180205-100509462", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.jclepro.2018.01.206", "pub_year": "2018", "author_list": "Wang, Jiaoyue; Xi, Fengming; et al." }, { "id": "https://authors.library.caltech.edu/records/qrz5z-fcr89", "eprint_id": 84697, "eprint_status": "archive", "datestamp": "2023-08-21 23:12:00", "lastmod": "2023-10-18 16:37:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hunter-B-M", "name": { "family": "Hunter", "given": "Bryan M." }, "orcid": "0000-0001-8559-9304" }, { "id": "Thompson-N-B", "name": { "family": "Thompson", "given": "Niklas B." }, "orcid": "0000-0003-2745-4945" }, { "id": "M\u00fcller-A-M", "name": { "family": "M\u00fcller", "given": "Astrid M." }, "orcid": "0000-0002-2785-6808" }, { "id": "Rossman-G-R", "name": { "family": "Rossman", "given": "George R." }, "orcid": "0000-0002-4571-6884" }, { "id": "Hill-M-G", "name": { "family": "Hill", "given": "Michael G." } }, { "id": "Winkler-J-R", "name": { "family": "Winkler", "given": "Jay R." }, "orcid": "0000-0002-4453-9716" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Trapping an Iron(VI) Water-Splitting Intermediate in Nonaqueous Media", "ispublished": "pub", "full_text_status": "public", "keywords": "electrocatalysis; water splitting; water oxidation; solar fuels; spectroscopy; layered double hydroxides; in situ electrochemistry; spectroelectrochemistry; catalysis", "note": "\u00a9 2018 Elsevier Inc. \n\nReceived: December 20, 2017. Revised: January 8, 2018. Accepted: January 11, 2018. Published: February 6, 2018. \n\nThis work was supported by the NSF CCI Solar Fuels Program ( CHE- 1305124 ) and the Arnold and Mabel Beckman Foundation, with additional support from NSF EAR-1322082 . B.M.H. is a Fellow of the Resnick Sustainability Institute at Caltech. The authors thank Jonas Peters for helpful discussions. Additional data and methods are available in the Supplemental Information. \n\nAuthor Contributions: B.M.H. designed and performed the experiments; N.B.T. collected and analyzed the M\u00f6ssbauer spectra; A.M.M. synthesized and characterized the materials; G.R.R. assisted with luminescence and Raman electrochemistry; M.G.H. assisted with electrochemistry and IR spectroelectrochemistry; J.R.W. and H.B.G., with the other authors, developed the proposed mechanism. All authors wrote the manuscript. \n\nThe authors declare no competing interests.\n\n

Supplemental Material - mmc1.pdf

", "abstract": "We report in situ spectroscopic measurements in nonaqueous media designed to trap an exceptionally strong oxidant generated electrochemically from an iron-containing nickel layered double hydroxide ([NiFe]-LDH) material. Anodic polarization of this material in acetonitrile produces metal-oxo vibrational spectroscopic signatures along with an extremely narrow near-infrared luminescence peak that strongly indicate that the reactive intermediate is cis-dioxo-iron(VI). Chemical trapping experiments reveal that addition of H_2O to the polarized electrochemical cell produces hydrogen peroxide; and, most importantly, addition of HO\u2013 generates oxygen. Repolarization of the electrode restores the iron(VI) spectroscopic features, confirming that the high-valent oxo complex is active in the electrocatalytic water oxidation cycle.", "date": "2018-04-18", "date_type": "published", "publication": "Joule", "volume": "2", "number": "4", "publisher": "Elsevier", "pagerange": "747-763", "id_number": "CaltechAUTHORS:20180207-065509383", "issn": "2542-4351", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180207-065509383", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE- 1305124" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "NSF", "grant_number": "EAR-1322082" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.joule.2018.01.008", "primary_object": { "basename": "mmc1.pdf", "url": "https://authors.library.caltech.edu/records/qrz5z-fcr89/files/mmc1.pdf" }, "pub_year": "2018", "author_list": "Hunter, Bryan M.; Thompson, Niklas B.; et al." }, { "id": "https://authors.library.caltech.edu/records/z7qnr-p0m91", "eprint_id": 82615, "eprint_status": "archive", "datestamp": "2023-08-21 23:09:10", "lastmod": "2023-10-17 22:33:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Directed Evolution: Bringing New Chemistry to Life", "ispublished": "pub", "full_text_status": "public", "keywords": "biocatalysis; enzymes; heme proteins; protein engineering; synthetic methods", "note": "\u00a9 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co.\nKGaA. This is an open access article under the terms of the Creative Commons Attribution Non-Commercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited, and is not used for commercial purposes. \n\nVersion of record online: 28 November 2017; Accepted manuscript online: 24 October 2017; Manuscript Received: 15 August 2017. \n\nI thank Sabine Brinkmann-Chen, Kai Chen, Stephan Hammer, Kari Hernandez, Xiongyi Huang, Jennifer Kan, Rusty Lewis, Chris Prier and Ruijie Zhang for the ideas, inspiration, data, and hard work that went into the examples presented here. I thank Kim Mayer for excellent editorial assistance. This work was supported by the National Science Foundation, Division of Molecular and Cellular Biosciences (grant MCB-1513007), the Resnick Sustainability Institute, and the Caltech CI2 innovation program. \n\nThe author declares no conflict of interest.\n\n

Published - ANIE-57-4143.pdf

", "abstract": "Tailor-made: Discussed herein is the ability to adapt biology's mechanisms for innovation and optimization to solving problems in chemistry and engineering. The evolution of nature's enzymes can lead to the discovery of new reactivity, transformations not known in biology, and reactivity inaccessible by small-molecule catalysts.", "date": "2018-04-09", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "57", "number": "16", "publisher": "Wiley", "pagerange": "4143-4148", "id_number": "CaltechAUTHORS:20171024-105338006", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171024-105338006", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Innovation Initiative (CI2)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201708408", "pmcid": "PMC5901037", "primary_object": { "basename": "ANIE-57-4143.pdf", "url": "https://authors.library.caltech.edu/records/z7qnr-p0m91/files/ANIE-57-4143.pdf" }, "pub_year": "2018", "author_list": "Arnold, Frances H." }, { "id": "https://authors.library.caltech.edu/records/dvdsb-cs813", "eprint_id": 85240, "eprint_status": "archive", "datestamp": "2023-08-21 23:08:50", "lastmod": "2023-10-18 18:00:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brandenberg-O-F", "name": { "family": "Brandenberg", "given": "Oliver F." }, "orcid": "0000-0001-5662-1234" }, { "id": "Prier-C-K", "name": { "family": "Prier", "given": "Christopher K." }, "orcid": "0000-0003-0902-1636" }, { "id": "Chen-Kai", "name": { "family": "Chen", "given": "Kai" }, "orcid": "0000-0002-3325-3536" }, { "id": "Knight-A-M", "name": { "family": "Knight", "given": "Anders M." }, "orcid": "0000-0001-9665-8197" }, { "id": "Wu-Zachary", "name": { "family": "Wu", "given": "Zachary" } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Stereoselective Enzymatic Synthesis of Heteroatom-Substituted Cyclopropanes", "ispublished": "pub", "full_text_status": "public", "keywords": "biocatalysis; carbene transfer; cyclopropanes; Cytochrome P450", "note": "\u00a9 2018 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: December 23, 2017; Revised: February 7, 2018;\nPublication Date (Web): February 24, 2018. \n\nWe thank Dr. Stephan Hammer for help with chiral separations of cyclopropylamines and all members of the Arnold Laboratory for stimulating comments and discussions. We thank Dr. David Rozzell for suggestions on cyclopropanation substrate scope. \n\nAuthor Contributions: The manuscript was written with contributions of all authors. All authors have given approval to the final version of the manuscript.\n\nThis work was supported in part by the National Science Foundation, Division of Molecular and Cellular Biosciences (Grant No. MCB-1513007) and the Defense Advanced Research Projects Agency Biological Robustness in Complex Settings Contract HR0011-15-C-0093. O.F.B. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG Grant No. BR 5238/1-1) and the Swiss National Science Foundation (SNF Grant No. P300PA-171225). C.K.P. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. A.M.K. and Z.W. acknowledge support from the NSF Graduate Research Fellowship (Grant No. 1745301), and A.M.K. acknowledges support from Caltech's Center for Environmental Microbial Interactions. \n\nThe authors declare no competing financial interest.\n\n

Published - acscatal.7b04423.pdf

Supplemental Material - cs7b04423_si_001.cif

Supplemental Material - cs7b04423_si_002.pdf

", "abstract": "The repurposing of hemoproteins for non-natural carbene transfer activities has generated enzymes for functions previously accessible only to chemical catalysts. With activities constrained to specific substrate classes, however, the synthetic utility of these new biocatalysts has been limited. To expand the capabilities of non-natural carbene transfer biocatalysis, we engineered variants of Cytochrome P450_(BM3) that catalyze the cyclopropanation of heteroatom-bearing alkenes, providing valuable nitrogen-, oxygen-, and sulfur-substituted cyclopropanes. Four or five active-site mutations converted a single parent enzyme into selective catalysts for the synthesis of both cis and trans heteroatom-substituted cyclopropanes, with high diastereoselectivities and enantioselectivities and up to 40\u202f000 total turnovers. This work highlights the ease of tuning hemoproteins by directed evolution for efficient cyclopropanation of new substrate classes and expands the catalytic functions of iron heme proteins.", "date": "2018-04-06", "date_type": "published", "publication": "ACS Catalysis", "volume": "8", "number": "4", "publisher": "American Chemical Society", "pagerange": "2629-2634", "id_number": "CaltechAUTHORS:20180312-085606768", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180312-085606768", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "HR0011-15-C-0093" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "BR 5238/1-1" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300PA-171225" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Caltech Center for Environmental Microbial Interactions (CEMI)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Caltech-Center-for-Environmental-Microbial-Interactions-(CEMI)" }, { "id": "Rosen-Bioengineering-Center" } ] }, "doi": "10.1021/acscatal.7b04423", "primary_object": { "basename": "cs7b04423_si_002.pdf", "url": "https://authors.library.caltech.edu/records/dvdsb-cs813/files/cs7b04423_si_002.pdf" }, "related_objects": [ { "basename": "acscatal.7b04423.pdf", "url": "https://authors.library.caltech.edu/records/dvdsb-cs813/files/acscatal.7b04423.pdf" }, { "basename": "cs7b04423_si_001.cif", "url": "https://authors.library.caltech.edu/records/dvdsb-cs813/files/cs7b04423_si_001.cif" } ], "pub_year": "2018", "author_list": "Brandenberg, Oliver F.; Prier, Christopher K.; et al." }, { "id": "https://authors.library.caltech.edu/records/wxyrd-a4p23", "eprint_id": 85964, "eprint_status": "archive", "datestamp": "2023-08-21 23:04:51", "lastmod": "2023-10-18 19:08:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hunter-Bryan-M", "name": { "family": "Hunter", "given": "Bryan M." }, "orcid": "0000-0001-8559-9304" }, { "id": "Winkler-Jay-R", "name": { "family": "Winkler", "given": "Jay R." }, "orcid": "0000-0002-4453-9716" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Iron Is the Active Site in Nickel/Iron Water Oxidation Electrocatalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "oxygen evolution reaction; layered double hydroxide; electrocatalyst", "note": "\u00a9 2018 The Author(s). This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0). \n\nReceived: 28 February 2018 / Revised: 10 April 2018 / Accepted: 12 April 2018 / Published: 14 April 2018. \n\n(This article belongs to the Special Issue Artificial Photosynthesis: Recent Progress in Solar Energy Utilization).\n\nThis work was supported by the NSF CCI Solar Fuels Program (CHE-1305124) and the Arnold and Mabel Beckman Foundation. B.M.H. acknowledges a Fellowship from the Resnick Sustainability Institute at Caltech. \n\nThe authors declare no conflict of interest.\n\n

Published - molecules-23-00903.pdf

", "abstract": "Efficient catalysis of the oxygen-evolution half-reaction (OER) is a pivotal requirement for the development of practical solar-driven water splitting devices. Heterogeneous OER electrocatalysts containing first-row transition metal oxides and hydroxides have attracted considerable recent interest, owing in part to the high abundance and low cost of starting materials. Among the best performing OER electrocatalysts are mixed Fe/Ni layered double hydroxides (LDH). A review of the available experimental data leads to the conclusion that iron is the active site for [NiFe]-LDH-catalyzed alkaline water oxidation.", "date": "2018-04", "date_type": "published", "publication": "Molecules", "volume": "23", "number": "4", "publisher": "MDPI", "pagerange": "Art. No. 903", "id_number": "CaltechAUTHORS:20180418-165501153", "issn": "1420-3049", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180418-165501153", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" } ] }, "doi": "10.3390/molecules23040903", "pmcid": "PMC6017163", "primary_object": { "basename": "molecules-23-00903.pdf", "url": "https://authors.library.caltech.edu/records/wxyrd-a4p23/files/molecules-23-00903.pdf" }, "pub_year": "2018", "author_list": "Hunter, Bryan M.; Winkler, Jay R.; et al." }, { "id": "https://authors.library.caltech.edu/records/3vsjv-73n39", "eprint_id": 85426, "eprint_status": "archive", "datestamp": "2023-08-19 08:30:51", "lastmod": "2023-10-18 18:13:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ren-Xiaoqi", "name": { "family": "Ren", "given": "Xiaoqi" }, "orcid": "0000-0002-1121-9046" }, { "id": "London-P", "name": { "family": "London", "given": "Palma" } }, { "id": "Ziani-Juba", "name": { "family": "Ziani", "given": "Juba" }, "orcid": "0000-0002-3324-4349" }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" } } ] }, "title": "Datum: Managing Data Purchasing and Data Placement in a Geo-Distributed Data Market", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Data market, geo-distributed analytics", "note": "\u00a9 2018 IEEE. \n\nManuscript received April 13, 2017; revised October 14, 2017 and February 2, 2018; accepted February 3, 2018; approved by IEEE/ACM TRANSACTIONS ON NETWORKING Editor M. Mellia. \n\nThis work was supported in part by the National Science Foundation under Grant 1254169, Grant 1518941, Grant 1331343, and Grant 1637598, in part by the National Science Foundation Graduate Fellowship, and in part by the Resnick Sustainability Institute Fellowship.", "abstract": "This paper studies two design tasks faced by a geo-distributed cloud data market: which data to purchase (data purchasing) and where to place/replicate the data for delivery (data placement). We show that the joint problem of data purchasing and data placement within a cloud data market can be viewed as a facility location problem and is thus NP-hard. However, we give a provably optimal algorithm for the case of a data market made up of a single data center and then generalize the structure from the single data center setting in order to develop a near-optimal, polynomial-time algorithm for a geo-distributed data market. The resulting design, Datum, decomposes the joint purchasing and placement problem into two subproblems, one for data purchasing and one for data placement, using a transformation of the underlying bandwidth costs. We show, via a case study, that Datum is near optimal (within 1.6%) in practical settings.", "date": "2018-04", "date_type": "published", "publication": "IEEE/ACM Transactions on Networking", "volume": "26", "number": "2", "publisher": "IEEE", "pagerange": "893-905", "id_number": "CaltechAUTHORS:20180323-104121108", "issn": "1063-6692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180323-104121108", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-1254169" }, { "agency": "NSF", "grant_number": "CNS-1518941" }, { "agency": "NSF", "grant_number": "CCF-1331343" }, { "agency": "NSF", "grant_number": "CCF-1637598" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TNET.2018.2811374", "pub_year": "2018", "author_list": "Ren, Xiaoqi; London, Palma; et al." }, { "id": "https://authors.library.caltech.edu/records/8e3sd-9xk88", "eprint_id": 85328, "eprint_status": "archive", "datestamp": "2023-08-19 08:30:43", "lastmod": "2025-04-25 22:01:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Yuxiu", "name": { "family": "Wang", "given": "Yixiu" } }, { "id": "Qiu-Gang", "name": { "family": "Qiu", "given": "Gang" } }, { "id": "Wang-Ruoxing", "name": { "family": "Wang", "given": "Ruoxing" } }, { "id": "Huang-Shouyuan", "name": { "family": "Huang", "given": "Shouyuan" } }, { "id": "Wang-Qingxiao", "name": { "family": "Wang", "given": "Qingxiao" } }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Du-Yuchen", "name": { "family": "Du", "given": "Yuchen" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Kim-Moon-J", "name": { "family": "Kim", "given": "Moon J." } }, { "id": "Xu-Xianfan", "name": { "family": "Xu", "given": "Xianfan" } }, { "id": "Yu-Peide-D", "name": { "family": "Ye", "given": "Peide D." } }, { "id": "Wu-Wenzhuo", "name": { "family": "Wu", "given": "Wenzhuo" }, "orcid": "0000-0003-0362-6650" } ] }, "title": "Field-effect transistors made from solution-grown two-dimensional tellurene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 Macmillan Publishers Limited, part of Springer Nature. \n\nReceived: 25 October 2017; Accepted: 16 March 2018; Published online: 17 April 2018. \n\nW.Z.W. acknowledges the College of Engineering and School of Industrial Engineering at Purdue University for startup support. W.Z.W. was partially supported by a grant from the Oak Ridge Associated Universities (ORAU) Junior Faculty Enhancement Award Program. Part of the solution synthesis work was supported by the National Science Foundation (grant no. CMMI-1663214). P.D.Y. was supported by the NSF/AFOSR 2DARE Program, ARO and SRC. Q.W. and M.J.K. were supported by the Center for Low Energy Systems Technology (LEAST) and the South West Academy of Nanoelectronics (SWAN). Y.L. acknowledges support from Resnick Prize Postdoctoral Fellowship at Caltech, and startup support from UT Austin. Y.L. and W.A.G. were supported as part of the Computational Materials Sciences Program funded by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences (award no. DE-SC00014607). This work used the computational resources of NREL (sponsored by DOE EERE), XSEDE (NSF ACI-1053575), NERSC (DOE DE-AC02-05CH11231) and the Texas Advanced Computing Center (TACC) at UT Austin. The authors thank F. Fan for discussions. \n\nThese authors contributed equally: Yixiu Wang, Gang Qiu and Ruoxing Wang. \n\nAuthor Contributions: W.Z.W. and P.D.Y. conceived and supervised the project. W.Z.W., P.D.Y., Y.X.W. and G.Q. designed the experiments. Y.X.W. and R.X.W. synthesized the material. G.Q. and Y.X.W. fabricated the devices. G.Q. and Y.C.D. performed the electrical and optical characterization. S.Y.H. and Y.X.W. performed the Raman measurements under the supervision of X.F.X. and W.Z.W. Q.W. and M.J.K. performed TEM characterization. Y.L. carried out the first-principles calculations under the supervision of W.A.G. Y.X.W. and G.Q. conducted the experiments. W.Z.W., P.D.Y., Y.X.W., G.Q. and R.X.W. analysed the data. W.Z.W. and P.D.Y. wrote the manuscript. Y.X.W., G.Q. and R.X.W. contributed equally to this work. All authors discussed the results and commented on the paper. \n\nData availability: The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request. \n\nThe authors declare no competing interests.\n\n

Accepted Version - NatureElectronics-FET-Te-YuanhuaLiu-WenzhuoWu.pdf

Submitted - 1704.06202.pdf

Supplemental Material - 41928_2018_58_MOESM1_ESM.pdf

", "abstract": "The reliable production of two-dimensional (2D) crystals is essential for the development of new technologies based on 2D materials. However, current synthesis methods suffer from a variety of drawbacks, including limitations in crystal size and stability. Here, we report the fabrication of large-area, high-quality 2D tellurium (tellurene) using a substrate-free solution process. Our approach can create crystals with process-tunable thickness, from a monolayer to tens of nanometres, and with lateral sizes of up to 100\u2009\u00b5m. The chiral-chain van der Waals structure of tellurene gives rise to strong in-plane anisotropic properties and large thickness-dependent shifts in Raman vibrational modes, which is not observed in other 2D layered materials. We also fabricate tellurene field-effect transistors, which exhibit air-stable performance at room temperature for over two months, on/off ratios on the order of 106, and field-effect mobilities of about 700\u2009cm^2\u2009V^(\u22121)\u2009s^(\u22121). Furthermore, by scaling down the channel length and integrating with high-k dielectrics, transistors with a significant on-state current density of 1\u2009A\u2009mm^(\u22121) are demonstrated.", "date": "2018-04", "date_type": "published", "publication": "Nature Electronics", "volume": "1", "number": "4", "publisher": "Nature Publishing Group", "pagerange": "228-236", "id_number": "CaltechAUTHORS:20180315-092800939", "issn": "2520-1131", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180315-092800939", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Purdue University" }, { "agency": "Oak Ridge Associated Universities" }, { "agency": "NSF", "grant_number": "CMMI-1663214" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Army Research Office (ARO)" }, { "agency": "Center for Low Energy Systems Technology (LEAST)" }, { "agency": "South West Academy of Nanoelectronics (SWAN)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of Texas at Austin" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1276", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41928-018-0058-4", "primary_object": { "basename": "1704.06202.pdf", "url": "https://authors.library.caltech.edu/records/8e3sd-9xk88/files/1704.06202.pdf" }, "related_objects": [ { "basename": "41928_2018_58_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/8e3sd-9xk88/files/41928_2018_58_MOESM1_ESM.pdf" }, { "basename": "NatureElectronics-FET-Te-YuanhuaLiu-WenzhuoWu.pdf", "url": "https://authors.library.caltech.edu/records/8e3sd-9xk88/files/NatureElectronics-FET-Te-YuanhuaLiu-WenzhuoWu.pdf" } ], "pub_year": "2018", "author_list": "Wang, Yixiu; Qiu, Gang; et al." }, { "id": "https://authors.library.caltech.edu/records/y767f-w2r98", "eprint_id": 85331, "eprint_status": "archive", "datestamp": "2023-08-19 08:27:01", "lastmod": "2023-10-18 18:06:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chapovetsky-Alon", "name": { "family": "Chapovetsky", "given": "Alon" }, "orcid": "0000-0001-8095-8830" }, { "id": "Welborn-Matthew-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Luna-M", "name": { "family": "Luna", "given": "M." } }, { "id": "Haiges-Ralf", "name": { "family": "Haiges", "given": "Ralf" }, "orcid": "0000-0003-4151-3593" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Marinescu-Smaranda-C", "name": { "family": "Marinescu", "given": "Smaranda C." }, "orcid": "0000-0003-2106-8971" } ] }, "title": "Pendant Hydrogen-Bond Donors in Cobalt Catalysts Independently Enhance CO\u2082 Reduction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: December 19, 2017. Published: February 23, 2018. \n\nThis work was supported by the University of Southern California and the National Science Foundation (NSF) through the CAREER award (CHE-1555387) and the Chemistry of Life Processes Program (CHE-1611581). This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We are grateful to the USC Wrigley Institute for a Norma and Jerol Sonosky summer fellowship to A.C. M.W. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. We are grateful to NSF (Grant CRIF 1048807) and USC for their sponsorship of NMR spectrometers and an X-ray diffractometer. \n\nA.C. and M.W.: equal contribution. \n\nCCDC 1590218\u20131590221 contain the supplementary crystallographic data for this manuscript. \n\nThe authors declare no competing financial interest.\n\n

Published - acscentsci.7b00607.pdf

Supplemental Material - oc7b00607_si_001.pdf

Supplemental Material - oc7b00607_si_002.cif

Supplemental Material - oc7b00607_si_003.cif

Supplemental Material - oc7b00607_si_004.cif

Supplemental Material - oc7b00607_si_005.cif

", "abstract": "The bioinspired incorporation of pendant proton donors into transition metal catalysts is a promising strategy for converting environmentally deleterious CO\u2082 to higher energy products. However, the mechanism of proton transfer in these systems is poorly understood. Herein, we present a series of cobalt complexes with varying pendant secondary and tertiary amines in the ligand framework with the aim of disentangling the roles of the first and second coordination spheres in CO\u2082 reduction catalysis. Electrochemical and kinetic studies indicate that the rate of catalysis shows a first-order dependence on acid, CO\u2082, and the number of pendant secondary amines, respectively. Density functional theory studies explain the experimentally observed trends and indicate that pendant secondary amines do not directly transfer protons to CO\u2082, but instead bind acid molecules from solution. Taken together, these results suggest a mechanism in which noncooperative pendant amines facilitate a hydrogen-bonding network that enables direct proton transfer from acid to the activated CO\u2082 substrate.", "date": "2018-03-28", "date_type": "published", "publication": "ACS Central Science", "volume": "4", "number": "3", "publisher": "American Chemical Society", "pagerange": "397-404", "id_number": "CaltechAUTHORS:20180315-111119688", "issn": "2374-7943", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180315-111119688", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1555387" }, { "agency": "NSF", "grant_number": "CHE-1611581" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CHE-1048807" }, { "agency": "University of Southern California" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscentsci.7b00607", "pmcid": "PMC5879468", "primary_object": { "basename": "oc7b00607_si_004.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_004.cif" }, "related_objects": [ { "basename": "oc7b00607_si_005.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_005.cif" }, { "basename": "acscentsci.7b00607.pdf", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/acscentsci.7b00607.pdf" }, { "basename": "oc7b00607_si_001.pdf", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_001.pdf" }, { "basename": "oc7b00607_si_002.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_002.cif" }, { "basename": "oc7b00607_si_003.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_003.cif" } ], "pub_year": "2018", "author_list": "Chapovetsky, Alon; Welborn, Matthew; et al." }, { "id": "https://authors.library.caltech.edu/records/t4r8k-v6w44", "eprint_id": 85304, "eprint_status": "archive", "datestamp": "2023-08-19 08:25:34", "lastmod": "2025-04-23 00:51:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ilic-O", "name": { "family": "Ilic", "given": "Ognjen" } }, { "id": "Thomas-Nathan-H", "name": { "family": "Thomas", "given": "Nathan H." }, "orcid": "0000-0003-4648-5325" }, { "id": "Christensen-T", "name": { "family": "Christensen", "given": "Thomas" } }, { "id": "Sherrott-M-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Solja\u010di\u0107-M", "name": { "family": "Solja\u010di\u0107", "given": "Marin" } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" }, { "id": "Miller-O-D", "name": { "family": "Miller", "given": "Owen D." }, "orcid": "0000-0003-2745-2392" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Active Radiative Thermal Switching with Graphene Plasmon Resonators", "ispublished": "pub", "full_text_status": "public", "keywords": "graphene, thermal radiation, near-field radiative heat transfer, surface plasmon", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: November 20, 2017; Accepted: March 12, 2018;\nPublished: March 12, 2018. \n\nO.I., N.H.T., M.C.S, A.J.M., and H.A.A. were supported as part of the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under award no. DE-SC0001293. O.I., M.C.S., and H.A.A. acknowledge support from the Northrop Grumman Corporation through NG Next. M.C.S. acknowledges fellowship support from the Resnick Sustainability Institute. O.D.M. was supported by the Air Force Office of Scientific Research under award no. FA9550-17-1-0093. T.C. was supported by the Danish Council for Independent Research (grant DFFC6108-00667). M.S. was supported as part of the Army Research Office through the Institute for Soldier Nanotechnologies under contract no. W911NF-13-D-0001 (photon management for developing nuclear-TPV and fuel-TPV mm-scale-systems). M.S. was also supported as part of the S3TEC, an Energy Frontier Research Center funded by the US Department of Energy under grant no. DE-SC0001299 (for fundamental photon transport related to solar TPVs and solar-TEs). \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nn7b08231_si_001.pdf

", "abstract": "We theoretically demonstrate a near-field radiative thermal switch based on thermally excited surface plasmons in graphene resonators. The high tunability of graphene enables substantial modulation of near-field radiative heat transfer, which, when combined with the use of resonant structures, overcomes the intrinsically broadband nature of thermal radiation. In canonical geometries, we use nonlinear optimization to show that stacked graphene sheets offer improved heat conductance contrast between \"ON\" and \"OFF\" switching states and that a >10\u00d7 higher modulation is achieved between isolated graphene resonators than for parallel graphene sheets. In all cases, we find that carrier mobility is a crucial parameter for the performance of a radiative thermal switch. Furthermore, we derive shape-agnostic analytical approximations for the resonant heat transfer that provide general scaling laws and allow for direct comparison between different resonator geometries dominated by a single mode. The presented scheme is relevant for active thermal management and energy harvesting as well as probing excited-state dynamics at the nanoscale.", "date": "2018-03-27", "date_type": "published", "publication": "ACS Nano", "volume": "12", "number": "3", "publisher": "American Chemical Society", "pagerange": "2474-2481", "id_number": "CaltechAUTHORS:20180314-101708544", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180314-101708544", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-17-1-0093" }, { "agency": "Danish Council for Independent Research", "grant_number": "DFFC6108-00667" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-13-D-0001" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001299" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsnano.7b08231", "primary_object": { "basename": "nn7b08231_si_001.pdf", "url": "https://authors.library.caltech.edu/records/t4r8k-v6w44/files/nn7b08231_si_001.pdf" }, "pub_year": "2018", "author_list": "Ilic, Ognjen; Thomas, Nathan H.; et al." }, { "id": "https://authors.library.caltech.edu/records/kxsta-y5z15", "eprint_id": 84844, "eprint_status": "archive", "datestamp": "2023-08-19 08:24:28", "lastmod": "2023-10-18 16:45:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Drover-Marcus-W", "name": { "family": "Drover", "given": "Marcus W." }, "orcid": "0000-0002-2186-1040" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Expanding the allyl analogy: accessing \u03b7\u00b3-P,B,P diphosphinoborane complexes of group 10", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nReceived 6th January 2018, Accepted 2nd February 2018. First published on 5th February 2018. \n\nThis work was supported by the NIH (GM070757), NSERC (Banting PDF award to MWD), and the Resnick Sustainability Institute at Caltech (Postdoctoral award to MWD). We thank Larry Henling and Mike Takase for assistance with X-ray crystallography. \n\nThere are no conflicts to declare.\n\n

Accepted Version - nihms-974447.pdf

Supplemental Material - c8dt00058a1_si.pdf

Supplemental Material - c8dt00058a2.cif

", "abstract": "Using the diphosphinoborane, (PPh\u2082)\u2082BMes (Mes = 2,4,6-Me\u2083\u20866H\u2083), we report the first examples of \u03b7\u00b3-P,B,P-ligated complexes using Ni(0) and Pt(II). Reaction of (PPh\u2082)\u2082BMes with Ni(COD)\u2082 or Pt(COD)Me\u2082 (COD = 1,5-cyclooctadiene) results in gradual COD displacement to give [\u03b7\u00b3-P,B,P-(PPh\u2082)\u2082BMes]Ni(COD) (3) or [\u03b7\u00b3-P,B,P-(PPh\u2082)\u2082BMes]Pt(CH\u2083)\u2082 (6). Complex 3 serves as a versatile Ni-containing synthon for the preparation of square planar or tetrahedral Ni(0) complexes. Notably, the M\u2013B interaction in these systems is non-negligible \u2013 with coordination resulting in an upfield shift of ca. 80 ppm in the \u00b9\u00b9B NMR spectrum. We also show that treatment of the Pt^(IV) halide precursor, [PtMe\u2083I]\u2084 with this ligand framework results in migration of X-type ligands (CH\u2083\u2212 and I\u2212) to boron and reductive elimination of ethane (C\u2082H\u2086) to give a distorted square planar zwitterionic Pt^(II) complex, Pt[\u03ba^2-P,P-(PPh\u2082)\u2082B(Mes)(CH\u2083)][\u03ba\u00b2-P,P-(PPh\u2082)\u2082B(Mes)(I)] (10). This reactivity suggests the feasibility of (PPh\u2082)\u2082BMes-ligand-induced labilization of M\u2013X ligands.", "date": "2018-03-21", "date_type": "published", "publication": "Dalton Transactions", "volume": "47", "number": "11", "publisher": "Royal Society of Chemistry", "pagerange": "3733-3738", "id_number": "CaltechAUTHORS:20180215-085923720", "issn": "1477-9226", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180215-085923720", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM070757" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c8dt00058a", "pmcid": "PMC6005356", "primary_object": { "basename": "c8dt00058a1_si.pdf", "url": "https://authors.library.caltech.edu/records/kxsta-y5z15/files/c8dt00058a1_si.pdf" }, "related_objects": [ { "basename": "c8dt00058a2.cif", "url": "https://authors.library.caltech.edu/records/kxsta-y5z15/files/c8dt00058a2.cif" }, { "basename": "nihms-974447.pdf", "url": "https://authors.library.caltech.edu/records/kxsta-y5z15/files/nihms-974447.pdf" } ], "pub_year": "2018", "author_list": "Drover, Marcus W. and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/nva4j-q2786", "eprint_id": 84261, "eprint_status": "archive", "datestamp": "2023-08-19 08:17:06", "lastmod": "2025-04-25 21:58:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Chen", "name": { "family": "Wang", "given": "Chen" }, "orcid": "0000-0001-9565-8777" }, { "id": "He-Qiyuan", "name": { "family": "He", "given": "Qiyuan" } }, { "id": "Halim-U", "name": { "family": "Halim", "given": "Udayabagya" } }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Enbo-Zhu", "name": { "family": "Enbo", "given": "Zhu" } }, { "id": "Lin-Zhaoyang", "name": { "family": "Lin", "given": "Zhaoyang" }, "orcid": "0000-0002-6474-7184" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" }, { "id": "Feng-Ziying", "name": { "family": "Feng", "given": "Ziying" } }, { "id": "Cheng-Rui", "name": { "family": "Cheng", "given": "Rui" } }, { "id": "Weiss-N-O", "name": { "family": "Weiss", "given": "Nathan O." } }, { "id": "Ye-Guojun", "name": { "family": "Ye", "given": "Guojun" } }, { "id": "Huang-Yun-Chiao", "name": { "family": "Huang", "given": "Yun-Chiao" } }, { "id": "Wu-Hao", "name": { "family": "Wu", "given": "Hao" } }, { "id": "Cheng-Hung-Chieh", "name": { "family": "Cheng", "given": "Hung-Chieh" } }, { "id": "Shakir-I", "name": { "family": "Shakir", "given": "Imran" } }, { "id": "Liao-Lei", "name": { "family": "Liao", "given": "Lei" } }, { "id": "Chen-Xianhui", "name": { "family": "Chen", "given": "Xianhui" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" } ] }, "title": "Monolayer atomic crystal molecular superlattices", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 Macmillan Publishers Limited. \n\nreceived 20 January 2017; accepted 17 January 2018. \n\nThe authors acknowledge the Electron Imaging Center for NanoMachines (EICN) at California NanoSystem Institute (CNSI) and Nanoelectronic Research Facility (NRF) at UCLA for technical support. Xiangfeng D. acknowledges support by National Science Foundation DMR1508144 (materials synthesis) and Office of Naval Research through grant number N00014-15-1-2368 (device fabrications). Y.H. acknowledges support by National Science Foundation EFRI-1433541. Y.L. was supported by a Resnick Prize Postdoctoral Fellowship at Caltech. L.L. acknowledges support through the 973 grant of MOST (No. 2013CBA01604). X.H.C. acknowledges support from the National Natural Science Foundation of China (Grant No. 11534010). W.A.G. and Y.L. were also supported by DOE DE-SC0014607. W.A.G acknowledges the Extreme Science and Engineering Discovery Environment (XSEDE) supported by National Science Foundation grant ACI-1053575. Y.L. acknowledges the computational resources sponsored by the DOE's Office of Energy Efficiency and Renewable Energy and located at the National Renewable Energy Laboratory, and the Texas Advanced Computing Center (TACC). I.S. thanks the Deanship of Scientific Research at King Saud University for its funding of this research through grant PEJP-17-01. \n\nAuthor Contributions: Xiangfeng D., Y.H. and C.W. co-designed the research. C.W. conducted device fabrication, electrical properties measurements and data analysis. C.W., Q.H. and U.H. conducted the intercalation experiments. C.W., U.H., Z.L. and Z.F. conducted structural and optical characterizations. Y.L., H.X. and W.A.G. contributed to the superlattice atomic and electronic structure calculations. E.Z. conducted the TEM studies. Q.H., Xidong D., Y.-C.H., H.W., H.-C.C., I.S. and L.L. contributed to the initial measurement system set-up, preparation of 2D materials and data analysis. R.C. contributed to the initial BP property characterization. N.O.W. contributed to the schematic drawing. G.J.Y. and X.H.C. prepared the initial BP material. Y.H. and Xiangfeng D. supervised the research. Xiangfeng D. and C.W. co-wrote the manuscript. All authors discussed the results and commented on the manuscript. \n\nData availability: The data that support the findings of this study are available from the corresponding author on reasonable request. \n\nThe authors declare no competing financial interests. \n\nNature thanks N. Guisinger, K. Loh and Q. Xiong for their contribution to the peer review of this work.\n\n

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Supplemental Material - nature25774-st1.jpg

", "abstract": "Artificial superlattices, based on van der Waals heterostructures of two-dimensional atomic crystals such as graphene or molybdenum disulfide, offer technological opportunities beyond the reach of existing materials. Typical strategies for creating such artificial superlattices rely on arduous layer-by-layer exfoliation and restacking, with limited yield and reproducibility. The bottom-up approach of using chemical-vapour deposition produces high-quality heterostructures but becomes increasingly difficult for high-order superlattices. The intercalation of selected two-dimensional atomic crystals with alkali metal ions offers an alternative way to superlattice structures, but these usually have poor stability and seriously altered electronic properties. Here we report an electrochemical molecular intercalation approach to a new class of stable superlattices in which monolayer atomic crystals alternate with molecular layers. Using black phosphorus as a model system, we show that intercalation with cetyl-trimethylammonium bromide produces monolayer phosphorene molecular superlattices in which the interlayer distance is more than double that in black phosphorus, effectively isolating the phosphorene monolayers. Electrical transport studies of transistors fabricated from the monolayer phosphorene molecular superlattice show an on/off current ratio exceeding 10^7, along with excellent mobility and superior stability. We further show that several different two-dimensional atomic crystals, such as molybdenum disulfide and tungsten diselenide, can be intercalated with quaternary ammonium molecules of varying sizes and symmetries to produce a broad class of superlattices with tailored molecular structures, interlayer distances, phase compositions, electronic and optical properties. These studies define a versatile material platform for fundamental studies and potential technological applications.", "date": "2018-03-08", "date_type": "published", "publication": "Nature", "volume": "555", "number": "7695", "publisher": "Nature Publishing Group", "pagerange": "231-236", "id_number": "CaltechAUTHORS:20180111-131636552", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180111-131636552", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1508144" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-15-1-2368" }, { "agency": "NSF", "grant_number": "EFRI-1433541" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Ministry of Science and Technology (China)", "grant_number": "2013CBA01604" }, { "agency": "National Natural Science Foundation of China", "grant_number": "11534010" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014607" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "King Saud University", "grant_number": "PEJP-17-01" } ] }, "other_numbering_system": { "items": [ { "id": "1272", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nature25774", "primary_object": { "basename": "nature25774-sf3.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf3.jpg" }, "related_objects": [ { "basename": "nature25774-sf4.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf4.jpg" }, { "basename": "nature25774-sf5.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf5.jpg" }, { "basename": "nature25774-sf6.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf6.jpg" }, { "basename": "nature25774-sf7.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf7.jpg" }, { "basename": "nature25774-st1.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-st1.jpg" }, { "basename": "nature25774-sf1.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf1.jpg" }, { "basename": "nature25774-sf2.jpg", "url": "https://authors.library.caltech.edu/records/nva4j-q2786/files/nature25774-sf2.jpg" } ], "pub_year": "2018", "author_list": "Wang, Chen; He, Qiyuan; et al." }, { "id": "https://authors.library.caltech.edu/records/1e18c-ft246", "eprint_id": 84857, "eprint_status": "archive", "datestamp": "2023-08-19 08:13:35", "lastmod": "2023-10-18 16:46:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cid-Cl\u00e9ment-A", "name": { "family": "Cid", "given": "Clement A." }, "orcid": "0000-0002-7293-035X" }, { "id": "Jasper-Justin-T", "name": { "family": "Jasper", "given": "Justin T." }, "orcid": "0000-0002-2461-5283" }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" } ] }, "title": "Phosphate Recovery from Human Waste via the Formation of Hydroxyapatite during Electrochemical Wastewater Treatment", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrochemical precipitation, Phosphorus, Phosphate removal, Wastewater, Onsite sanitation", "note": "\u00a9 2018 American Chemical Society. ACS AuthorChoice - This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. \n\nReceived: September 7, 2017; Revised: February 1, 2018;\nPublished: February 5, 2018. \n\nThis research was supported by the Bill and Melinda Gates Foundation (Grants OPP 1069500 and OPP 1111246) and a Resnick Sustainability Postdoctoral Fellowship to J.T.J. \n\nC.A.C. and J.T.J. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Published - acssuschemeng.7b03155.pdf

Supplemental Material - sc7b03155_si_001.pdf

", "abstract": "Electrolysis of toilet wastewater with TiO_2-coated semiconductor anodes and stainless steel cathodes is a potentially viable onsite sanitation solution in parts of the world without infrastructure for centralized wastewater treatment. In addition to treating toilet wastewater, pilot-scale and bench-scale experiments demonstrated that electrolysis can remove phosphate by cathodic precipitation as hydroxyapatite at no additional energy cost. Phosphate removal could be predicted based on initial phosphate and calcium concentrations, and up to 80% total phosphate removal was achieved. While calcium was critical for phosphate removal, magnesium and bicarbonate had only minor impacts on phosphate removal rates at concentrations typical of toilet wastewater. Optimal conditions for phosphate removal were 3 to 4 h treatment at about 5 mA cm^(\u20132) (\u223c3.4 V), with greater than 20 m^2 m^(\u20133) electrode surface area to reactor volume ratios. Pilot-scale systems are currently operated under similar conditions, suggesting that phosphate removal can be viewed as an ancillary benefit of electrochemical wastewater treatment, adding utility to the process without requiring additional energy inputs. Further value may be provided by designing reactors to recover precipitated hydroxyapatite for use as a low solubility phosphorus-rich fertilizer.", "date": "2018-03-05", "date_type": "published", "publication": "ACS Sustainable Chemistry & Engineering", "volume": "6", "number": "3", "publisher": "American Chemical Society", "pagerange": "3135-3142", "id_number": "CaltechAUTHORS:20180215-163923294", "issn": "2168-0485", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180215-163923294", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP 1069500" }, { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP 1111246" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acssuschemeng.7b03155", "pmcid": "PMC5871340", "primary_object": { "basename": "acssuschemeng.7b03155.pdf", "url": "https://authors.library.caltech.edu/records/1e18c-ft246/files/acssuschemeng.7b03155.pdf" }, "related_objects": [ { "basename": "sc7b03155_si_001.pdf", "url": "https://authors.library.caltech.edu/records/1e18c-ft246/files/sc7b03155_si_001.pdf" } ], "pub_year": "2018", "author_list": "Cid, Clement A.; Jasper, Justin T.; et al." }, { "id": "https://authors.library.caltech.edu/records/g2nqq-42g09", "eprint_id": 84690, "eprint_status": "archive", "datestamp": "2023-08-19 07:47:33", "lastmod": "2023-10-18 16:37:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vyatskikh-Andrey", "name": { "family": "Vyatskikh", "given": "Andrey" }, "orcid": "0000-0002-6917-6931" }, { "id": "Delalande-St\u00e9phane", "name": { "family": "Delalande", "given": "St\u00e9phane" } }, { "id": "Kudo-Akira", "name": { "family": "Kudo", "given": "Akira" }, "orcid": "0000-0002-0830-5509" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" }, "orcid": "0000-0002-6155-6825" }, { "id": "Portela-Carlos-M", "name": { "family": "Portela", "given": "Carlos M." }, "orcid": "0000-0002-2649-4235" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Additive manufacturing of 3D nano-architected metals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Authors. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived: 25 September 2017 Accepted: 17 January 2018. Published online: 09 February 2018. \n\nThe authors gratefully acknowledge the financial support of JRG's Vannevar-Bush Faculty Fellowship through the Department of Defense. \n\nAuthor Contributions: A.V., S.D. and J.R.G. conceived the concept. A.V. performed synthesis, fabrication, SEM and EDS characterization. S.D. provided information on how to prepare the photoresist. A.K. performed TEM characterization and analysis. X.Z. and C.M.P. performed nanocompression experiments and analyzed the results. A.V. and J.R.G. wrote the manuscript. All authors commented on the manuscript. J.R.G. supervised the project. \n\nData availability: The data that support the findings of this study are available from the corresponding author upon reasonable request. \n\nThe authors declare no competing financial interests.\n\n

Published - s41467-018-03071-9.pdf

Supplemental Material - 41467_2018_3071_MOESM1_ESM.pdf

Supplemental Material - 41467_2018_3071_MOESM2_ESM.pdf

Supplemental Material - 41467_2018_3071_MOESM3_ESM.docx

Supplemental Material - 41467_2018_3071_MOESM4_ESM.mp4

", "abstract": "Most existing methods for additive manufacturing (AM) of metals are inherently limited to ~20\u201350\u2009\u03bcm resolution, which makes them untenable for generating complex 3D-printed metallic structures with smaller features. We developed a lithography-based process to create complex 3D nano-architected metals with ~100\u2009nm resolution. We first synthesize hybrid organic\u2013inorganic materials that contain Ni clusters to produce a metal-rich photoresist, then use two-photon lithography to sculpt 3D polymer scaffolds, and pyrolyze them to volatilize the organics, which produces a >90\u2009wt% Ni-containing architecture. We demonstrate nanolattices with octet geometries, 2\u2009\u03bcm unit cells and 300\u2013400-nm diameter beams made of 20-nm grained nanocrystalline, nanoporous Ni. Nanomechanical experiments reveal their specific strength to be 2.1\u20137.2\u2009MPa\u2009g^(\u22121)\u2009cm^3, which is comparable to lattice architectures fabricated using existing metal AM processes. This work demonstrates an efficient pathway to 3D-print micro-architected and nano-architected metals with sub-micron resolution.", "date": "2018-02-09", "date_type": "published", "publication": "Nature Communications", "volume": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 593", "id_number": "CaltechAUTHORS:20180206-130051890", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180206-130051890", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Vannever Bush Faculty Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Rosen-Bioengineering-Center" } ] }, "doi": "10.1038/s41467-018-03071-9", "pmcid": "PMC5807385", "primary_object": { "basename": "41467_2018_3071_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/g2nqq-42g09/files/41467_2018_3071_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2018_3071_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/g2nqq-42g09/files/41467_2018_3071_MOESM2_ESM.pdf" }, { "basename": "41467_2018_3071_MOESM3_ESM.docx", "url": "https://authors.library.caltech.edu/records/g2nqq-42g09/files/41467_2018_3071_MOESM3_ESM.docx" }, { "basename": "41467_2018_3071_MOESM4_ESM.mp4", "url": "https://authors.library.caltech.edu/records/g2nqq-42g09/files/41467_2018_3071_MOESM4_ESM.mp4" }, { "basename": "s41467-018-03071-9.pdf", "url": "https://authors.library.caltech.edu/records/g2nqq-42g09/files/s41467-018-03071-9.pdf" } ], "pub_year": "2018", "author_list": "Vyatskikh, Andrey; Delalande, St\u00e9phane; et al." }, { "id": "https://authors.library.caltech.edu/records/zvyct-ckp56", "eprint_id": 85498, "eprint_status": "archive", "datestamp": "2023-08-21 22:42:44", "lastmod": "2023-10-18 18:16:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gui-Lili", "name": { "family": "Gui", "given": "Lili" } }, { "id": "Wang-Pan", "name": { "family": "Wang", "given": "Pan" } }, { "id": "Ding-Yihang", "name": { "family": "Ding", "given": "Yihang" } }, { "id": "Zhao-Kangjun", "name": { "family": "Zhao", "given": "Kangjun" } }, { "id": "Bao-Chengying", "name": { "family": "Bao", "given": "Chengying" } }, { "id": "Xiao-Xiaosheng", "name": { "family": "Xiao", "given": "Xiaosheng" } }, { "id": "Yang-Changxi", "name": { "family": "Yang", "given": "Changxi" }, "orcid": "0000-0002-9972-6965" } ] }, "title": "Soliton Molecules and Multisoliton States in Ultrafast Fibre Lasers: Intrinsic Complexes in Dissipative Systems", "ispublished": "pub", "full_text_status": "public", "keywords": "soliton molecules; bound states; fibre lasers; nonlinear interaction; ultrafast nonlinear optics; fibre optics", "note": "\u00a9 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nPublished by MDPI AG, Basel, Switzerland. \n\nReceived: 14 December 2017; Revised: 18 January 2018; Accepted: 23 January 2018; Published: 29 January 2018. \n\nThis work was financially supported by the National Natural Science Foundation of China (NSFC) (61377039, 61575106 and 51527901). Lili Gui additionally acknowledges financial support from the Carl-Zeiss-Stiftung for her research in Germany. Chengying Bao acknowledges a fellowship from the Resnick Institute, Caltech. \n\nAuthor Contributions: Lili Gui and Changxi Yang conceived the original idea; Lili Gui, Pan Wang and Chengying Bao summarized and analysed the main experimental results; Lili Gui, Yihang Ding and Kangjun Zhao analysed the state of the art and contributed to numerical simulation; Lili Gui, Changxi Yang, Pan Wang and Chengying Bao discussed the nonlinear interaction mechanisms; all authors discussed and wrote this manuscript. \n\nThe authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript and in the decision to publish the results.\n\n

Published - applsci-08-00201.pdf

", "abstract": "Benefiting from ultrafast temporal resolution, broadband spectral bandwidth, as well as high peak power, passively mode-locked fibre lasers have attracted growing interest and exhibited great potential from fundamental sciences to industrial and military applications. As a nonlinear system containing complex interactions from gain, loss, nonlinearity, dispersion, etc., ultrafast fibre lasers deliver not only conventional single soliton but also soliton bunching with different types. In analogy to molecules consisting of several atoms in chemistry, soliton molecules (in other words, bound solitons) in fibre lasers are of vital importance for in-depth understanding of the nonlinear interaction mechanism and further exploration for high-capacity fibre-optic communications. In this Review, we summarize the state-of-the-art advances on soliton molecules in ultrafast fibre lasers. A variety of soliton molecules with different numbers of soliton, phase-differences and pulse separations were experimentally observed owing to the flexibility of parameters such as mode-locking techniques and dispersion control. Numerical simulations clearly unravel how different nonlinear interactions contribute to formation of soliton molecules. Analysis of the stability and the underlying physical mechanisms of bound solitons bring important insights to this field. For a complete view of nonlinear optical phenomena in fibre lasers, other dissipative states such as vibrating soliton pairs, soliton rains, rogue waves and coexisting dissipative solitons are also discussed. With development of advanced real-time detection techniques, the internal motion of different pulsing states is anticipated to be characterized, rendering fibre lasers a versatile platform for nonlinear complex dynamics and various practical applications.", "date": "2018-02", "date_type": "published", "publication": "Applied Sciences", "volume": "8", "number": "2", "publisher": "MDPI", "pagerange": "Art. No. 201", "id_number": "CaltechAUTHORS:20180329-123556060", "issn": "2076-3417", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180329-123556060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "61377039" }, { "agency": "National Natural Science Foundation of China", "grant_number": "61575106" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51527901" }, { "agency": "Carl-Zeiss-Stiftung" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3390/app8020201", "primary_object": { "basename": "applsci-08-00201.pdf", "url": "https://authors.library.caltech.edu/records/zvyct-ckp56/files/applsci-08-00201.pdf" }, "pub_year": "2018", "author_list": "Gui, Lili; Wang, Pan; et al." }, { "id": "https://authors.library.caltech.edu/records/q3ngd-cq343", "eprint_id": 84432, "eprint_status": "archive", "datestamp": "2023-08-19 07:25:01", "lastmod": "2025-04-23 00:54:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Papadakis-Georgia-T", "name": { "family": "Papadakis", "given": "Georgia T." }, "orcid": "0000-0001-8107-9221" }, { "id": "Fleischman-Dagny", "name": { "family": "Fleischman", "given": "Dagny" } }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur" }, "orcid": "0000-0002-4662-1158" }, { "id": "Yeh-Pochi", "name": { "family": "Yeh", "given": "Pochi" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Optical magnetism in planar metamaterial heterostructures", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived: 16 May 2017; Accepted: 11 December 2017; Published online: 18 January 2018. \n\nThis work was supported by U.S. Department of Energy (DOE) Office of Science grant DE-FG02-07ER46405 (G.T.P. and H.A.A.) and the Air Force Office of Scientific Research (A.D.) under grant FA9550-16-1-0019. G.T.P. acknowledges support by the National Science Foundation Graduate Research Fellowship, the American Association of University Women Dissertation Fellowship, and NG NEXT at Northrop Grumman Corporation. We acknowledge fruitful discussions with Dr T. Tiwald, Dr R. Pala, Dr K. Thyagarajan, Dr C. Santis, Dr O. Ilic, Dr L. Sweatlock, Dr G. Tagliabue, K. Mauser, Dr V. F. Chernow, and J.E. Herriman. We also thank C. Garland and B. Baker for assistance with sample preparation. \n\nAuthor Contributions: G.T.P. developed the theoretical model together with A.D., carried out the numerical simulations and calculations, the experimental measurements and ellipsometric fittings. D.F. fabricated the samples and took the TEM images. A.D. also contributed to the finite elements simulations. P.Y. and H.A.A. contributed to the parameter retrieval and underlying physics. H.A.A. supervised the project. All authors contributed to the preparation of the manuscript. \n\nThe authors declare no competing financial interests.\n\n

Published - s41467-017-02589-8.pdf

Submitted - 1608.02909.pdf

Supplemental Material - 41467_2017_2589_MOESM1_ESM.pdf

", "abstract": "Harnessing artificial optical magnetism has previously required complex two- and three-dimensional structures, such as nanoparticle arrays and split-ring metamaterials. By contrast, planar structures, and in particular dielectric/metal multilayer metamaterials, have been generally considered non-magnetic. Although the hyperbolic and plasmonic properties of these systems have been extensively investigated, their assumed non-magnetic response limits their performance to transverse magnetic (TM) polarization. We propose and experimentally validate a mechanism for artificial magnetism in planar multilayer metamaterials. We also demonstrate that the magnetic properties of high-index dielectric/metal hyperbolic metamaterials can be anisotropic, leading to magnetic hyperbolic dispersion in certain frequency regimes. We show that such systems can support transverse electric polarized interface-bound waves, analogous to their TM counterparts, surface plasmon polaritons. Our results open a route for tailoring optical artificial magnetism in lithography-free layered systems and enable us to generalize the plasmonic and hyperbolic properties to encompass both linear polarizations.", "date": "2018-01-18", "date_type": "published", "publication": "Nature Communications", "volume": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 296", "id_number": "CaltechAUTHORS:20180119-154213290", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180119-154213290", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0019" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "American Association of University Women" }, { "agency": "Northrop Grumman Corporation" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-017-02589-8", "pmcid": "PMC5773539", "primary_object": { "basename": "1608.02909.pdf", "url": "https://authors.library.caltech.edu/records/q3ngd-cq343/files/1608.02909.pdf" }, "related_objects": [ { "basename": "41467_2017_2589_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/q3ngd-cq343/files/41467_2017_2589_MOESM1_ESM.pdf" }, { "basename": "s41467-017-02589-8.pdf", "url": "https://authors.library.caltech.edu/records/q3ngd-cq343/files/s41467-017-02589-8.pdf" } ], "pub_year": "2018", "author_list": "Papadakis, Georgia T.; Fleischman, Dagny; et al." }, { "id": "https://authors.library.caltech.edu/records/6vd04-h9q50", "eprint_id": 79119, "eprint_status": "archive", "datestamp": "2023-08-19 07:13:37", "lastmod": "2025-04-25 03:16:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moon-Jaeyun", "name": { "family": "Moon", "given": "Jaeyun" } }, { "id": "Latour-B", "name": { "family": "Latour", "given": "Benoit" } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Propagating elastic vibrations dominate thermal conduction in amorphous silicon", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Physical Society. \n\nReceived 26 April 2017; revised manuscript received 15 December 2017; published 10 January 2018. \n\nThis work was supported by the Samsung Scholarship, NSF CAREER Award No. CBET 1254213, and the Resnick Fellowship from the Resnick Sustainability Institute at Caltech.\n\n

Published - PhysRevB.97.024201.pdf

Submitted - 1704.08360.pdf

", "abstract": "The thermal atomic vibrations of amorphous solids can be distinguished by whether they propagate as elastic waves or do not propagate due to lack of atomic periodicity. In \na-Si, prior works concluded that nonpropagating waves are the dominant contributors to heat transport, with propagating waves being restricted to frequencies less than a few THz and scattered by anharmonicity. Here, we present a lattice and molecular dynamics analysis of vibrations in \na-Si that supports a qualitatively different picture in which propagating elastic waves dominate the thermal conduction and are scattered by local fluctuations of elastic modulus rather than anharmonicity. We explicitly demonstrate the propagating nature of waves up to around 10 THz, and further show that pseudoperiodic structures with homogeneous elastic properties exhibit a marked temperature dependence characteristic of anharmonic interactions. Our work suggests that most heat is carried by propagating elastic waves in a-Si and demonstrates that manipulating local elastic modulus variations is a promising route to realize amorphous materials with extreme thermal properties.", "date": "2018-01-01", "date_type": "published", "publication": "Physical Review B", "volume": "97", "number": "2", "publisher": "American Physical Society", "pagerange": "Art. No. 024201", "id_number": "CaltechAUTHORS:20170717-075759713", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170717-075759713", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Samsung Scholarship" }, { "agency": "NSF", "grant_number": "CBET-1254213" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.97.024201", "primary_object": { "basename": "PhysRevB.97.024201.pdf", "url": "https://authors.library.caltech.edu/records/6vd04-h9q50/files/PhysRevB.97.024201.pdf" }, "related_objects": [ { "basename": "1704.08360.pdf", "url": "https://authors.library.caltech.edu/records/6vd04-h9q50/files/1704.08360.pdf" } ], "pub_year": "2018", "author_list": "Moon, Jaeyun; Latour, Benoit; et al." }, { "id": "https://authors.library.caltech.edu/records/6cs9r-be370", "eprint_id": 78206, "eprint_status": "archive", "datestamp": "2023-08-21 22:27:04", "lastmod": "2023-10-25 23:52:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taeb-A", "name": { "family": "Taeb", "given": "Armeen" }, "orcid": "0000-0002-5647-3160" }, { "id": "Chandrasekaran-V", "name": { "family": "Chandrasekaran", "given": "Venkat" } } ] }, "title": "Interpreting Latent Variables in Factor Models via Convex Optimization", "ispublished": "pub", "full_text_status": "public", "keywords": "Canonical correlations analysis; Factor analysis; Log-determinant optimization; Minimum-trace factor analysis; Nuclear-norm relaxation; Semidefinite programming", "note": "\u00a9 2017 Springer-Verlag GmbH Germany and Mathematical Optimization Society. \n\nReceived: 2 December 2015; Accepted: 3 August 2017; First Online: 06 September 2017. \n\nThe authors were supported in part by NSF Career Award CCF-1350590, by Air Force Office of Scientific Research Grant Nos. FA9550-14-1-0098 and FA9550-16-1-0210, by a Sloan research fellowship, and the Resnick Sustainability Institute at Caltech. Armeen Taeb would like to thank Yong Sheng Soh for many helpful discussions.\n\n

Submitted - 1601.00389.pdf

Supplemental Material - 10107_2017_1187_MOESM1_ESM.pdf

", "abstract": "Latent or unobserved phenomena pose a significant difficulty in data analysis as they induce complicated and confounding dependencies among a collection of observed variables. Factor analysis is a prominent multivariate statistical modeling approach that addresses this challenge by identifying the effects of (a small number of) latent variables on a set of observed variables. However, the latent variables in a factor model are purely mathematical objects that are derived from the observed phenomena, and they do not have any interpretation associated to them. A natural approach for attributing semantic information to the latent variables in a factor model is to obtain measurements of some additional plausibly useful covariates that may be related to the original set of observed variables, and to associate these auxiliary covariates to the latent variables. In this paper, we describe a systematic approach for identifying such associations. Our method is based on solving computationally tractable convex optimization problems, and it can be viewed as a generalization of the minimum-trace factor analysis procedure for fitting factor models via convex optimization. We analyze the theoretical consistency of our approach in a high-dimensional setting as well as its utility in practice via experimental demonstrations with real data.", "date": "2018-01", "date_type": "published", "publication": "Mathematical Programming", "volume": "167", "number": "1", "publisher": "Springer", "pagerange": "129-154", "id_number": "CaltechAUTHORS:20170614-105229927", "issn": "0025-5610", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170614-105229927", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1350590" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-14-1-0098" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0210" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s10107-017-1187-7", "primary_object": { "basename": "10107_2017_1187_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/6cs9r-be370/files/10107_2017_1187_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "1601.00389.pdf", "url": "https://authors.library.caltech.edu/records/6cs9r-be370/files/1601.00389.pdf" } ], "pub_year": "2018", "author_list": "Taeb, Armeen and Chandrasekaran, Venkat" }, { "id": "https://authors.library.caltech.edu/records/ce6s2-dxb87", "eprint_id": 82651, "eprint_status": "archive", "datestamp": "2023-08-19 06:55:42", "lastmod": "2023-10-17 22:34:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jariwala-D", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Davoyan-A-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Van der Waals Materials for Atomically-Thin Photovoltaics: Promise and Outlook", "ispublished": "pub", "full_text_status": "public", "keywords": "transition metal dichalcogenides, heterostructures, light-trapping, Shockley-Quessier, nanophotonics, 2D materials", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: September 22, 2017; Revised: October 10, 2017; Accepted: October 23, 2017; Published: October 23, 2017. \n\nThis work is part of the \"Light\u2013Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DE-SC0001293. D.J. and A.R.D. acknowledge additional support from the Space Solar Power project and the Resnick Sustainability Institute Graduate and Postdoctoral Fellowships. A.R.D. also acknowledges support in part from the Kavli Nanoscience Institute Postdoctoral Fellowship. J.W. acknowledges support from the National Science Foundation Graduate Research Fellowship under Grant No. 1144469. All the authors acknowledge support of the Space Solar Power Initiative at Caltech funded by the Northrop Grumman Corporation. \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1710.08917.pdf

", "abstract": "Two-dimensional (2D) semiconductors provide a unique opportunity for optoelectronics due to their layered atomic structure and electronic and optical properties. To date, a majority of the application-oriented research in this field has been focused on field-effect electronics as well as photodetectors and light emitting diodes. Here we present a perspective on the use of 2D semiconductors for photovoltaic applications. We discuss photonic device designs that enable light trapping in nanometer-thickness absorber layers, and we also outline schemes for efficient carrier transport and collection. We further provide theoretical estimates of efficiency indicating that 2D semiconductors can indeed be competitive with and complementary to conventional photovoltaics, based on favorable energy bandgap, absorption, external radiative efficiency, along with recent experimental demonstrations. Photonic and electronic design of 2D semiconductor photovoltaics represents a new direction for realizing ultrathin, efficient solar cells with applications ranging from conventional power generation to portable and ultralight solar power.", "date": "2017-12-20", "date_type": "published", "publication": "ACS Photonics", "volume": "4", "number": "12", "publisher": "American Chemical Society", "pagerange": "2962-2970", "id_number": "CaltechAUTHORS:20171025-101024290", "issn": "2330-4022", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171025-101024290", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Space Solar Power Project" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Northrop Grumman Corporation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "Space-Solar-Power-Project" } ] }, "doi": "10.1021/acsphotonics.7b01103", "primary_object": { "basename": "1710.08917.pdf", "url": "https://authors.library.caltech.edu/records/ce6s2-dxb87/files/1710.08917.pdf" }, "pub_year": "2017", "author_list": "Jariwala, Deep; Davoyan, Artur R.; et al." }, { "id": "https://authors.library.caltech.edu/records/9xngc-6zf31", "eprint_id": 83220, "eprint_status": "archive", "datestamp": "2023-09-22 22:39:39", "lastmod": "2023-10-23 23:26:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pi\u017el-M", "name": { "family": "Pi\u017el", "given": "Martin" } }, { "id": "Hunter-B-M", "name": { "family": "Hunter", "given": "Bryan M." }, "orcid": "0000-0001-8559-9304" }, { "id": "Greetham-G-M", "name": { "family": "Greetham", "given": "Gregory M." } }, { "id": "Towrie-M", "name": { "family": "Towrie", "given": "Michael" } }, { "id": "Z\u00e1li\u0161-S", "name": { "family": "Z\u00e1li\u0161", "given": "Stanislav" } }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Vl\u010dek-A", "name": { "family": "Vl\u010dek", "given": "Anton\u00edn" }, "orcid": "0000-0002-6413-8311" } ] }, "title": "Ultrafast Wiggling and Jiggling: Ir_2(1,8-diisocyanomenthane)_4^(2+)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: October 15, 2017; Published: November 13, 2017. \n\nThis work was supported by the Czech Science Foundation Grant 17-011375, NSF CCI Solar Fuels Program (CHE-1305124) and STFC (UK). B.M.H. is a Fellow of the Resnick Sustainability Institute at Caltech. Additional support was provided by the Arnold and Mabel Beckman Foundation, the Ministry of Education of the Czech Republic (Grant LTC17052), and COST Action CM1405. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - jp7b10215_si_001.pdf

", "abstract": "Binuclear complexes of d^8 metals (Pt^(II), Ir^I, Rh^I,) exhibit diverse photonic behavior, including dual emission from relatively long-lived singlet and triplet excited states, as well as photochemical energy, electron, and atom transfer. Time-resolved optical spectroscopic and X-ray studies have revealed the behavior of the dimetallic core, confirming that M\u2013M bonding is strengthened upon d\u03c3* \u2192 p\u03c3 excitation. We report the bridging ligand dynamics of Ir2(1,8-diisocyanomenthane)_4^(2+)(Ir(dimen)), investigated by fs\u2013ns time-resolved IR spectroscopy (TRIR) in the region of C\u2261N stretching vibrations, \u03bd(C\u2261N), 2000\u20132300 cm^(\u20131). The \u03bd(C\u2261N) IR band of the singlet and triplet d\u03c3*p\u03c3 excited states is shifted by \u221222 and \u221216 cm^(\u20131) relative to the ground state due to delocalization of the p\u03c3 LUMO over the bridging ligands. Ultrafast relaxation dynamics of the ^1d\u03c3*p\u03c3 state depend on the initially excited Franck\u2013Condon molecular geometry, whereby the same relaxed singlet excited state is populated by two different pathways depending on the starting point at the excited-state potential energy surface. Exciting the long/eclipsed isomer triggers two-stage structural relaxation: 0.5 ps large-scale Ir\u2013Ir contraction and 5 ps Ir\u2013Ir contraction/intramolecular rotation. Exciting the short/twisted isomer induces a \u223c5 ps bond shortening combined with vibrational cooling. Intersystem crossing (70 ps) follows, populating a ^3d\u03c3*p\u03c3 state that lives for hundreds of nanoseconds. During the first 2 ps, the \u03bd(C\u2261N) IR bandwidth oscillates with the frequency of the \u03bd(Ir\u2013Ir) wave packet, ca. 80 cm^(\u20131), indicating that the dephasing time of the high-frequency (16 fs)^(\u22121) C\u2261N stretch responds to much slower (\u223c400 fs)^(\u22121)Ir\u2013Ir coherent oscillations. We conclude that the bonding and dynamics of bridging di-isocyanide ligands are coupled to the dynamics of the metal\u2013metal unit and that the coherent Ir\u2013Ir motion induced by ultrafast excitation drives vibrational dephasing processes over the entire binuclear cation.", "date": "2017-12-07", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "121", "number": "48", "publisher": "American Chemical Society", "pagerange": "9275-9283", "id_number": "CaltechAUTHORS:20171115-101044605", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171115-101044605", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Czech Science Foundation", "grant_number": "17-011375" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Science and Technology Facilities Council (STFC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Ministry of Education (Czech Republic)", "grant_number": "LTC17052" }, { "agency": "European Cooperation in Science and Technology (COST)", "grant_number": "CM1405" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpca.7b10215", "primary_object": { "basename": "jp7b10215_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9xngc-6zf31/files/jp7b10215_si_001.pdf" }, "pub_year": "2017", "author_list": "Pi\u017el, Martin; Hunter, Bryan M.; et al." }, { "id": "https://authors.library.caltech.edu/records/fdc1q-bj584", "eprint_id": 83146, "eprint_status": "archive", "datestamp": "2023-08-19 06:31:28", "lastmod": "2023-10-17 22:56:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chang-Alice-B", "name": { "family": "Chang", "given": "Alice B." }, "orcid": "0000-0001-5036-2681" }, { "id": "Lin-Tzu-Pin", "name": { "family": "Lin", "given": "Tzu-Pin" }, "orcid": "0000-0001-7041-7213" }, { "id": "Thompson-N-B", "name": { "family": "Thompson", "given": "Niklas B." }, "orcid": "0000-0003-2745-4945" }, { "id": "Luo-Shao-Xiong", "name": { "family": "Luo", "given": "Shao-Xiong" }, "orcid": "0000-0001-5308-4576" }, { "id": "Liberman-Martin-A-L", "name": { "family": "Liberman-Martin", "given": "Allegra L." }, "orcid": "0000-0002-8447-905X" }, { "id": "Chen-Hsiang-Yun", "name": { "family": "Chen", "given": "Hsiang-Yun" }, "orcid": "0000-0002-6461-1519" }, { "id": "Lee-Byeongdu", "name": { "family": "Lee", "given": "Byeongdu" }, "orcid": "0000-0003-2514-8805" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Design, Synthesis, and Self-Assembly of Polymers with Tailored Graft Distributions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: October 6, 2017; Published: November 8, 2017. \n\nThis work was supported by the Department of Energy under Award Number DE-AR0000683 (ARPA-E Program) and by the National Science Foundation under Award Number CHE-1502616. A.B.C. thanks the U.S. Department of Defense for support through the NDSEG Fellowship. A.L.L.-M. thanks the Resnick Sustainability Institute at Caltech for fellowship support. The authors thank Prof. J. C. Peters for access to computational resources. This research used resources of the Advanced Photon Source, a U.S. Department of Energy Office of Science User Facility operated by Argonne National Laboratory under Contract DE-AC02-06CH11357. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja7b10525_si_001.pdf

", "abstract": "Grafting density and graft distribution impact the chain dimensions and physical properties of polymers. However, achieving precise control over these structural parameters presents long-standing synthetic challenges. In this report, we introduce a versatile strategy to synthesize polymers with tailored architectures via grafting-through ring-opening metathesis polymerization (ROMP). One-pot copolymerization of an \u03c9-norbornenyl macromonomer and a discrete norbornenyl comonomer (diluent) provides opportunities to control the backbone sequence and therefore the side chain distribution. Toward sequence control, the homopolymerization kinetics of 23 diluents were studied, representing diverse variations in the stereochemistry, anchor groups, and substituents. These modifications tuned the homopolymerization rate constants over 2 orders of magnitude (0.36 M^(\u20131) s^(\u20131) < k_(homo) < 82 M^(\u20131) s^(\u20131)). Rate trends were identified and elucidated by complementary mechanistic and density functional theory (DFT) studies. Building on this foundation, complex architectures were achieved through copolymerizations of selected diluents with a poly(D,L-lactide) (PLA), polydimethylsiloxane (PDMS), or polystyrene (PS) macromonomer. The cross-propagation rate constants were obtained by nonlinear least-squares fitting of the instantaneous comonomer concentrations according to the Mayo\u2013Lewis terminal model. In-depth kinetic analyses indicate a wide range of accessible macromonomer/diluent reactivity ratios (0.08 < r_1/r_2 < 20), corresponding to blocky, gradient, or random backbone sequences. We further demonstrated the versatility of this copolymerization approach by synthesizing AB graft diblock polymers with tapered, uniform, and inverse-tapered molecular \"shapes.\" Small-angle X-ray scattering analysis of the self-assembled structures illustrates effects of the graft distribution on the domain spacing and backbone conformation. Collectively, the insights provided herein into the ROMP mechanism, monomer design, and homo- and copolymerization rate trends offer a general strategy for the design and synthesis of graft polymers with arbitrary architectures. Controlled copolymerization therefore expands the parameter space for molecular and materials design.", "date": "2017-12-06", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "48", "publisher": "American Chemical Society", "pagerange": "17683-17693", "id_number": "CaltechAUTHORS:20171113-102011314", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171113-102011314", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "ARPA-E", "grant_number": "DE-AR0000683" }, { "agency": "NSF", "grant_number": "CHE-1502616" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.7b10525", "primary_object": { "basename": "ja7b10525_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fdc1q-bj584/files/ja7b10525_si_001.pdf" }, "pub_year": "2017", "author_list": "Chang, Alice B.; Lin, Tzu-Pin; et al." }, { "id": "https://authors.library.caltech.edu/records/p6tpf-bzs41", "eprint_id": 82832, "eprint_status": "archive", "datestamp": "2023-08-19 06:16:00", "lastmod": "2023-10-17 22:42:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mallada-E", "name": { "family": "Mallada", "given": "Enrique" }, "orcid": "0000-0003-1568-1833" }, { "id": "Zhao-Changhong", "name": { "family": "Zhao", "given": "Changhong" }, "orcid": "0000-0003-0539-8591" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven" }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Optimal Load-side Control for Frequency Regulation in Smart Grids", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Power system control, power system dynamics, optimization, demand-side management", "note": "\u00a9 2016 IEEE. \n\nManuscript received July 2, 2016; revised February 18, 2017; accepted May 1, 2017. Date of publication June 8, 2017; date of current version December 1, 2017. \n\nThis work was supported by NSF NetSE grant CNS 0911041, NSF CPS grant CNS 1544771, ARPA-E grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan R.O.C. grant NSC 103-3113-P-008-001, Caltech Resnick Institute, Johns Hopkins E2SHI Seed Grant, and Johns Hopkins WSE startup funds. \n\nThe authors would like to thank the associate editor and the\nanonymous reviewers whose valuable comments and suggestions considerably improved the manuscript.", "abstract": "Frequency control rebalances supply and demand while maintaining the network state within operational margins. It is implemented using fast ramping reserves that are expensive and wasteful, and which are expected to become increasingly necessary with the current acceleration of renewable penetration. The most promising solution to this problem is the use of demand response, i.e., load participation in frequency control. Yet it is still unclear how to efficiently integrate load participation without introducing instabilities and violating operational constraints. In this paper, we present a comprehensive load-side frequency control mechanism that can maintain the grid within operational constraints. In particular, our controllers can rebalance supply and demand after disturbances, restore the frequency to its nominal value, and preserve interarea power flows. Furthermore, our controllers are distributed (unlike the currently implemented frequency control), can allocate load updates optimally, and can maintain line flows within thermal limits. We prove that such a distributed load-side control is globally asymptotically stable and robust to unknown load parameters. We illustrate its effectiveness through simulations.", "date": "2017-12", "date_type": "published", "publication": "IEEE Transactions on Automatic Control", "volume": "62", "number": "12", "publisher": "IEEE", "pagerange": "6294-6309", "id_number": "CaltechAUTHORS:20171101-115726975", "issn": "0018-9286", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171101-115726975", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0911041" }, { "agency": "NSF", "grant_number": "CNS-1544771" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Johns Hopkins University" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TAC.2017.2713529", "pub_year": "2017", "author_list": "Mallada, Enrique; Zhao, Changhong; et al." }, { "id": "https://authors.library.caltech.edu/records/0v80w-hax34", "eprint_id": 82077, "eprint_status": "archive", "datestamp": "2023-08-21 22:13:45", "lastmod": "2023-10-17 22:01:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haibach-M-C", "name": { "family": "Haibach", "given": "Michael C." }, "orcid": "0000-0001-8383-5633" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Catalytic Reduction of Alkyl and Aryl Bromides Using Propan-2-ol", "ispublished": "pub", "full_text_status": "public", "keywords": "halogens; hydrogen transfer; green chemistry; hydrides; hydrocarbons", "note": "\u00a9 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nManuscript received: August 25, 2017; Accepted manuscript online: October 3, 2017; Version of record online: October 24, 2017.\n\nWe acknowledge funding from King Fahd University of Petroleum and Minerals. M.C.H. acknowledges funding from the Resnick Sustainability Institute in the form of a postdoctral fellowship. \n\nThe authors declare no conflict of interest.\n\n

Accepted Version - anie201708800.pdf

Supplemental Material - anie201708800-sup-0001-SI1.pdf

", "abstract": "Milstein's complex, (PNN)RuHCl(CO), catalyzes the efficient reduction of aryl and alkyl halides under relatively mild conditions by using propan-2-ol and a base. Sterically hindered tertiary and neopentyl substrates are reduced efficiently, as well as more functionalized aryl and alkyl bromides. The reduction process is proposed to occur by radical abstraction/hydrodehalogenation steps at ruthenium. Our research represents a safer and more sustainable alternative to typical silane, lithium aluminium hydride, and tin-based conditions for these reductions.", "date": "2017-11-20", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "56", "number": "47", "publisher": "Wiley", "pagerange": "15123-15126", "id_number": "CaltechAUTHORS:20171004-144313124", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171004-144313124", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "King Fahd University of Petroleum and Minerals (KFUPM)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201708800", "primary_object": { "basename": "anie201708800.pdf", "url": "https://authors.library.caltech.edu/records/0v80w-hax34/files/anie201708800.pdf" }, "related_objects": [ { "basename": "anie201708800-sup-0001-SI1.pdf", "url": "https://authors.library.caltech.edu/records/0v80w-hax34/files/anie201708800-sup-0001-SI1.pdf" } ], "pub_year": "2017", "author_list": "Haibach, Michael C.; Stoltz, Brian M.; et al." }, { "id": "https://authors.library.caltech.edu/records/95y3k-rra68", "eprint_id": 82617, "eprint_status": "archive", "datestamp": "2023-08-19 06:01:42", "lastmod": "2023-10-17 22:33:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liberman-Martin-A-L", "name": { "family": "Liberman-Martin", "given": "Allegra L." }, "orcid": "0000-0002-8447-905X" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Ruthenium Olefin Metathesis Catalysts Featuring a Labile Carbodicarbene Ligand", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: August 10, 2017. Publication Date (Web): October 23, 2017. \n\nThis work was supported by the National Science Foundation (CHE-1212767). A.L.L.-M. is grateful to the Resnick Sustainability Institute at Caltech for fellowship support. Dr. Michael K. Takase is acknowledged for X-ray crystallographic analysis, and Dr. Mona Shahgholi and Naseem Torian are acknowledged for mass spectrometry assistance. Dr. David VanderVelde is thanked for aid in NMR structural determination. Drs. William J. Wolf and Tzu-Pin Lin are thanked for helpful discussions and for synthesizing (H_2IPr)(py)_2(Cl)_2Ru\u2550CHPh and DEE, respectively. Materia, Inc. is thanked for generous donations of metathesis catalysts.\n\n

Supplemental Material - om7b00615_si_001.pdf

", "abstract": "Ruthenium benzylidene complexes containing a carbodicarbene (CDC) ligand are reported. Mechanistic studies indicate that the CDC ligand can dissociate under relatively mild conditions to afford active olefin metathesis catalysts. These catalysts were found to be effective at ring-closing metathesis (RCM) and ring-opening metathesis polymerization (ROMP) reactions.", "date": "2017-11-13", "date_type": "published", "publication": "Organometallics", "volume": "36", "number": "21", "publisher": "American Chemical Society", "pagerange": "4091-4094", "id_number": "CaltechAUTHORS:20171024-111203935", "issn": "0276-7333", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171024-111203935", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.organomet.7b00615", "primary_object": { "basename": "om7b00615_si_001.pdf", "url": "https://authors.library.caltech.edu/records/95y3k-rra68/files/om7b00615_si_001.pdf" }, "pub_year": "2017", "author_list": "Liberman-Martin, Allegra L. and Grubbs, Robert H." }, { "id": "https://authors.library.caltech.edu/records/3k56e-8df91", "eprint_id": 82539, "eprint_status": "archive", "datestamp": "2023-08-19 05:57:44", "lastmod": "2023-10-17 22:30:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Reed-Christopher-J", "name": { "family": "Reed", "given": "Christopher J." }, "orcid": "0000-0002-8774-5106" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Tetranuclear Fe Clusters with a Varied Interstitial Ligand: Effects on the Structure, Redox Properties, and Nitric Oxide Activation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: August 17, 2017. Publication Date (Web): October 20, 2017. \n\nThis research was supported by the NIH (Grant R01-GM102687B) and the Dreyfus Teacher\u2013Scholar Program (to T.A.). C.J.R. thanks the Resnick Sustainability Institute at Caltech for a fellowship. We thank Mike Takase and Larry Henling for assistance with crystallography and Jonas Peters for use of his laboratory's M\u00f6ssbauer spectrometer. C.J.R. is grateful to Graham de Ruiter and Niklas Thompson for insightful discussions. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms915080.pdf

Supplemental Material - ic7b02114_si_001.pdf

", "abstract": "A new series of tetranuclear Fe clusters displaying an interstitial \u03bc_4-F ligand was prepared for a comparison to previously reported \u03bc_4-O analogues. With a single nitric oxide (NO) coordinated as a reporter of small-molecule activation, the \u03bc_4-F clusters were characterized in five redox states, from Fe^(II)_3{FeNO}^8 to Fe^(III)_3{FeNO}^7, with NO stretching frequencies ranging from 1680 to 1855 cm^(\u20131), respectively. Despite accessing more reduced states with an F\u2013 bridge, a two-electron reduction of the distal Fe centers is necessary for the \u03bc_4-F clusters to activate NO to the same degree as the \u03bc_4-O system; consequently, NO reactivity is observed at more positive potentials with \u03bc_4-O than \u03bc_4-F. Moreover, the \u03bc_4-O ligand better translates redox changes of remote metal centers to diatomic ligand activation. The implication for biological active sites is that the higher-charge bridging ligand is more effective in tuning cluster properties, including the involvement of remote metal centers, for small-molecule activation.", "date": "2017-11-06", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "56", "number": "21", "publisher": "American Chemical Society", "pagerange": "13360-13367", "id_number": "CaltechAUTHORS:20171020-132701117", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171020-132701117", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01-GM102687B" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.7b02114", "pmcid": "PMC6277142", "primary_object": { "basename": "ic7b02114_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3k56e-8df91/files/ic7b02114_si_001.pdf" }, "related_objects": [ { "basename": "nihms915080.pdf", "url": "https://authors.library.caltech.edu/records/3k56e-8df91/files/nihms915080.pdf" } ], "pub_year": "2017", "author_list": "Reed, Christopher J. and Agapie, Theodor" }, { "id": "https://authors.library.caltech.edu/records/pv4vp-btx41", "eprint_id": 82248, "eprint_status": "archive", "datestamp": "2023-08-19 05:53:54", "lastmod": "2023-10-17 22:08:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thompson-Niklas-B", "name": { "family": "Thompson", "given": "Niklas B." }, "orcid": "0000-0003-2745-4945" }, { "id": "Green-Michael-T", "name": { "family": "Green", "given": "Michael T." } }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Nitrogen Fixation via a Terminal Fe(IV) Nitride", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: September 1, 2017; Published: October 9, 2017. \n\nWe thank M. Latimer, E. Nelson, C. Krest, C. Miller, and K. Mittra for assistance with synchrotron measurements. This work was supported by the Resnick Sustainability Institute at Caltech (Graduate Fellowship, N.B.T.), as well as the NIH (GM 070757). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. Additional notes in the Supporting Information. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-975149.pdf

Supplemental Material - ja7b09364_si_001.cif

Supplemental Material - ja7b09364_si_002.pdf

Supplemental Material - ja7b09364_si_003.pdf

", "abstract": "Terminal iron nitrides (Fe\u2261N) have been proposed as intermediates of (bio)catalytic nitrogen fixation, yet experimental evidence to support this hypothesis has been lacking. In particular, no prior synthetic examples of terminal Fe\u2261N species have been derived from N_2. Here we show that a nitrogen-fixing Fe\u2013N_2 catalyst can be protonated to form a neutral Fe(NNH_2) hydrazido(2\u2212) intermediate, which, upon further protonation, heterolytically cleaves the N\u2013N bond to release [Fe^(IV)\u2261N]^+ and NH_3. These observations provide direct evidence for the viability of a Chatt-type (distal) mechanism for Fe-mediated N_2-to-NH_3 conversion. The physical oxidation state range of the Fe complexes in this transformation is buffered by covalency with the ligand, a feature of possible relevance to catalyst design in synthetic and natural systems that facilitate multiproton/multielectron redox processes.", "date": "2017-11-01", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "43", "publisher": "American Chemical Society", "pagerange": "15312-15315", "id_number": "CaltechAUTHORS:20171010-095936880", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171010-095936880", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "GM-070757" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.7b09364", "pmcid": "PMC6021180", "primary_object": { "basename": "ja7b09364_si_001.cif", "url": "https://authors.library.caltech.edu/records/pv4vp-btx41/files/ja7b09364_si_001.cif" }, "related_objects": [ { "basename": "ja7b09364_si_002.pdf", "url": "https://authors.library.caltech.edu/records/pv4vp-btx41/files/ja7b09364_si_002.pdf" }, { "basename": "ja7b09364_si_003.pdf", "url": "https://authors.library.caltech.edu/records/pv4vp-btx41/files/ja7b09364_si_003.pdf" }, { "basename": "nihms-975149.pdf", "url": "https://authors.library.caltech.edu/records/pv4vp-btx41/files/nihms-975149.pdf" } ], "pub_year": "2017", "author_list": "Thompson, Niklas B.; Green, Michael T.; et al." }, { "id": "https://authors.library.caltech.edu/records/skkfa-xtx02", "eprint_id": 82556, "eprint_status": "archive", "datestamp": "2023-08-21 22:06:10", "lastmod": "2023-10-17 22:31:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taeb-A", "name": { "family": "Taeb", "given": "A." }, "orcid": "0000-0002-5647-3160" }, { "id": "Reager-J-T", "name": { "family": "Reager", "given": "J. T." }, "orcid": "0000-0001-7575-2520" }, { "id": "Turmon-M", "name": { "family": "Turmon", "given": "M." }, "orcid": "0000-0002-6463-063X" }, { "id": "Chandrasekaran-V", "name": { "family": "Chandrasekaran", "given": "V." } } ] }, "title": "A Statistical Graphical Model of the California Reservoir System", "ispublished": "pub", "full_text_status": "public", "keywords": "water resources; sustainability; graphical models; latent variables; convex optimization", "note": "\u00a9 2017 American Geophysical Union. \n\nReceived 13 JAN 2017; Accepted 14 OCT 2017; Accepted article online 20 OCT 2017. \n\nThe authors were supported in part by NSF Career award CCF-1350590, by Air Force Office of Scientific Research grants FA9550-14-1\u20130098 and FA9550-16-1\u20130210, by a Sloan research fellowship, and the Resnick Sustainability Institute at Caltech. A portion of this research was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. The data set and the code to produce the results of this paper can be found at https://github.com/armeentaeb/WRR-Reservoir.\n\n

Published - Taeb_et_al-2017-Water_Resources_Research.pdf

Submitted - 1606.08098.pdf

Supplemental Material - wrcr22962-sup-0001-TxtS01.pdf

Supplemental Material - wrcr22962-sup-0002-TxtS02.pdf

", "abstract": "The recent California drought has highlighted the potential vulnerability of the state's water management infrastructure to multiyear dry intervals. Due to the high complexity of the network, dynamic storage changes in California reservoirs on a state-wide scale have previously been difficult to model using either traditional statistical or physical approaches. Indeed, although there is a significant line of research on exploring models for single (or a small number of) reservoirs, these approaches are not amenable to a system-wide modeling of the California reservoir network due to the spatial and hydrological heterogeneities of the system. In this work, we develop a state-wide statistical graphical model to characterize the dependencies among a collection of 55 major California reservoirs across the state; this model is defined with respect to a graph in which the nodes index reservoirs and the edges specify the relationships or dependencies between reservoirs. We obtain and validate this model in a data-driven manner based on reservoir volumes over the period 2003\u20132016. A key feature of our framework is a quantification of the effects of external phenomena that influence the entire reservoir network. We further characterize the degree to which physical factors (e.g., state-wide Palmer Drought Severity Index (PDSI), average temperature, snow pack) and economic factors (e.g., consumer price index, number of agricultural workers) explain these external influences. As a consequence of this analysis, we obtain a system-wide health diagnosis of the reservoir network as a function of PDSI.", "date": "2017-11", "date_type": "published", "publication": "Water Resources Research", "volume": "53", "number": "11", "publisher": "American Geophysical Union", "pagerange": "9721-9739", "id_number": "CaltechAUTHORS:20171020-154910322", "issn": "0043-1397", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171020-154910322", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1350590" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-14-1-0098" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-021" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/2017WR020412", "primary_object": { "basename": "wrcr22962-sup-0001-TxtS01.pdf", "url": "https://authors.library.caltech.edu/records/skkfa-xtx02/files/wrcr22962-sup-0001-TxtS01.pdf" }, "related_objects": [ { "basename": "wrcr22962-sup-0002-TxtS02.pdf", "url": "https://authors.library.caltech.edu/records/skkfa-xtx02/files/wrcr22962-sup-0002-TxtS02.pdf" }, { "basename": "1606.08098.pdf", "url": "https://authors.library.caltech.edu/records/skkfa-xtx02/files/1606.08098.pdf" }, { "basename": "Taeb_et_al-2017-Water_Resources_Research.pdf", "url": "https://authors.library.caltech.edu/records/skkfa-xtx02/files/Taeb_et_al-2017-Water_Resources_Research.pdf" } ], "pub_year": "2017", "author_list": "Taeb, A.; Reager, J. T.; et al." }, { "id": "https://authors.library.caltech.edu/records/wmpzk-5c784", "eprint_id": 75052, "eprint_status": "archive", "datestamp": "2023-08-19 05:44:54", "lastmod": "2023-10-25 14:42:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fleischman-D", "name": { "family": "Fleischman", "given": "Dagny" } }, { "id": "Sweatlock-L-A", "name": { "family": "Sweatlock", "given": "Luke A." } }, { "id": "Murakami-Hirotaka", "name": { "family": "Murakami", "given": "Hirotaka" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry" }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Hyper-Selective Plasmonic Color Filters", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Optical Society of America. \n\nReceived 3 Aug 2017; revised 5 Oct 2017; accepted 11 Oct 2017; published 24 Oct 2017. \n\nFunding: Sony Corporation; the Hybrid Nanophotonics Multidisciplinary University Research Initiative Grant (Air Force Office of Scientific Research FA9550-12-1-0024); Northrop Grumman Corporation. \n\nLAS acknowledges support from the Resnick Sustainability Institute at Caltech. DF gratefully acknowledges helpful discussions with Michelle Sherrott, Max Jones, Matt Sullivan, and Charles Shaw. The facilities of the Kavli Nanoscience Institute (KNI) at Caltech are gratefully acknowledged.\n\n

Published - oe-25-22-27386.pdf

Submitted - 1612.01647.pdf

", "abstract": "The subwavelength mode volumes of plasmonic filters are well matched to the small size of state-of-the-art active pixels in CMOS image sensor arrays used in portable electronic devices. Typical plasmonic filters exhibit broad (> 100 nm) transmission bandwidths suitable for RBG or CMYK color filtering. Dramatically reducing the peak width of filter transmission spectra would allow for the realization of CMOS image sensors with multi- and hyperspectral imaging capabilities. We find that the design of 5 layer metal-insulator-metal-insulator-metal structures gives rise to multi-mode interference phenomena that suppress spurious transmission features and give rise to single transmission bands as narrow as 17 nm. The transmission peaks of these multilayer slot-mode plasmonic filters (MSPFs) can be systematically varied throughout the visible and near infrared spectrum, leading to a filter that is CMOS integrable, since the same basic MSPF structure can operate over a large range of wavelengths. We find that MSPF filter designs that can achieve a bandwidth less than 30 nm across the visible and demonstrate experimental prototypes with a FWHM of 70 nm, and we describe how experimental structure can be made to approach the limits suggested by the model.", "date": "2017-10-30", "date_type": "published", "publication": "Optics Express", "volume": "25", "number": "22", "publisher": "Optical Society of America", "pagerange": "27386-27395", "id_number": "CaltechAUTHORS:20170313-091445373", "issn": "1094-4087", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170313-091445373", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Sony Corporation" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0024" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1364/OE.25.027386", "primary_object": { "basename": "oe-25-22-27386.pdf", "url": "https://authors.library.caltech.edu/records/wmpzk-5c784/files/oe-25-22-27386.pdf" }, "related_objects": [ { "basename": "1612.01647.pdf", "url": "https://authors.library.caltech.edu/records/wmpzk-5c784/files/1612.01647.pdf" } ], "pub_year": "2017", "author_list": "Fleischman, Dagny; Sweatlock, Luke A.; et al." }, { "id": "https://authors.library.caltech.edu/records/wgzq6-d3438", "eprint_id": 82315, "eprint_status": "archive", "datestamp": "2023-08-19 05:37:23", "lastmod": "2023-10-17 22:11:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hammer-S-C", "name": { "family": "Hammer", "given": "Stephan C." }, "orcid": "0000-0002-3620-9362" }, { "id": "Kubik-G", "name": { "family": "Kubik", "given": "Grzegorz" } }, { "id": "Watkins-E-J", "name": { "family": "Watkins", "given": "Ella" }, "orcid": "0000-0002-7365-5791" }, { "id": "Huang-Shan", "name": { "family": "Huang", "given": "Shan" }, "orcid": "0000-0001-5575-4510" }, { "id": "Minges-H", "name": { "family": "Minges", "given": "Hannah" } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Anti-Markovnikov alkene oxidation by metal-oxo\u2013mediated enzyme catalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Association for the Advancement of Science. \n\nReceived 19 June 2017; accepted 5 September 2017. \n\nWe thank A. Buller, S. Brinkmann-Chen, K. Chen, P. Hanley (Dow Chemical Company), X. Huang, K. Mayer, C. Prier, D. Romney, and R. Zhang for fruitful discussions. This work was supported by the Deutsche Forschungsgemeinschaft (fellowships HA7668/1 to S.C.H. and KU3523/1 to G.K.) and by the Dow Chemical Company and the Resnick Sustainability Institute through the Dow/Resnick CI2 innovation program. All data necessary to support the conclusions are available in the supplementary materials. The work presented in this manuscript is part of a provisional patent filed with S.C.H. as inventor. Plasmids encoding the enzymes reported in this study are available for research purposes from F.H.A. under a material transfer agreement with the California Institute of Technology. S.C.H. designed the overall research project, with F.H.A. providing guidance. S.C.H., E.W., and H.M. designed and conducted directed evolution experiments. S.C.H., G.K., and S.H. designed and conducted the substrate scope studies. S.C.H., G.K., E.W., and F.H.A wrote the manuscript. The authors declare no competing financial interests.\n\n

Supplemental Material - aao1482_Hammer_SM.pdf

", "abstract": "Catalytic anti-Markovnikov oxidation of alkene feedstocks could simplify synthetic routes to many important molecules and solve a long-standing challenge in chemistry. Here we report the engineering of a cytochrome P450 enzyme by directed evolution to catalyze metal-oxo\u2013mediated anti-Markovnikov oxidation of styrenes with high efficiency. The enzyme uses dioxygen as the terminal oxidant and achieves selectivity for anti-Markovnikov oxidation over the kinetically favored alkene epoxidation by trapping high-energy intermediates and catalyzing an oxo transfer, including an enantioselective 1,2-hydride migration. The anti-Markovnikov oxygenase can be combined with other catalysts in synthetic metabolic pathways to access a variety of challenging anti-Markovnikov functionalization reactions.", "date": "2017-10-13", "date_type": "published", "publication": "Science", "volume": "358", "number": "6360", "publisher": "American Association for the Advancement of Science", "pagerange": "215-218", "id_number": "CaltechAUTHORS:20171012-132542523", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171012-132542523", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "HA7668/1" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "KU3523/1" }, { "agency": "Dow Chemical Company" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/science.aao1482", "primary_object": { "basename": "aao1482_Hammer_SM.pdf", "url": "https://authors.library.caltech.edu/records/wgzq6-d3438/files/aao1482_Hammer_SM.pdf" }, "pub_year": "2017", "author_list": "Hammer, Stephan C.; Kubik, Grzegorz; et al." }, { "id": "https://authors.library.caltech.edu/records/rdtkq-g8k55", "eprint_id": 81265, "eprint_status": "archive", "datestamp": "2023-08-19 05:29:28", "lastmod": "2023-10-17 19:42:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "MacFarland-C-A", "name": { "family": "MacFarland", "given": "Clara A." }, "orcid": "0000-0002-9570-948X" }, { "id": "Read-C-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Crystalline nickel manganese antimonate as a stable water-oxidation catalyst in aqueous 1.0 M H_2SO_4", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Royal Society of Chemistry. \n\nThe article was received on 28 May 2017, accepted on 10 Aug 2017 and first published on 10 Aug 2017. \n\nThis work is supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. I. M. H. acknowledges a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469. This work was also supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. C. G. R. acknowledges the Resnick Sustainability Institute for a post-doctoral fellowship. We thank N. Dalleska and P. Buabthong for assistance with mass spectroscopy measurements and X-ray photoelectron spectroscopy measurements, respectively.\n\n

Supplemental Material - c7ee01486d1.pdf

", "abstract": "Water oxidation is a required half-reaction for electrochemical water splitting. To date, the only well-established active oxygen-evolution catalysts stable under operating conditions and at rest in acidic aqueous media contain Ru or Ir, two of the scarcest non-radioactive elements on Earth. We report herein a nickel-manganese antimonate electrocatalyst with a rutile-type crystal structure that requires an initial voltammetric overpotential of 672 \u00b1 9 mV to catalyze the oxidation of water to O_2(g) at a rate corresponding to 10 mA cm^(\u22122) of current density when operated in contact with 1.0 M sulfuric acid. Under galvanostatic control, the overpotential initially rose from 670 mV but was then stable at 735 \u00b1 10 mV for 168 h of continuous operation at 10 mA cm^(\u22122). We additionally provide an in-depth evaluation of the stability of the nickel-manganese antimonate electrocatalyst, including elemental characterization of the surface, bulk, and electrolyte before and after electrochemical operation.", "date": "2017-10-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "2017", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2103-2108", "id_number": "CaltechAUTHORS:20170908-102102710", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170908-102102710", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C7EE01486D", "primary_object": { "basename": "c7ee01486d1.pdf", "url": "https://authors.library.caltech.edu/records/rdtkq-g8k55/files/c7ee01486d1.pdf" }, "pub_year": "2017", "author_list": "Moreno-Hernandez, Ivan A.; MacFarland, Clara A.; et al." }, { "id": "https://authors.library.caltech.edu/records/0fc0n-gva37", "eprint_id": 81148, "eprint_status": "archive", "datestamp": "2023-08-19 05:09:57", "lastmod": "2025-04-25 22:14:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johnson-S-I", "name": { "family": "Johnson", "given": "Samantha I." } }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Blakemore-J-D", "name": { "family": "Blakemore", "given": "James D." }, "orcid": "0000-0003-4172-7460" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Role of Ligand Protonation in Dihydrogen Evolution from a Pentamethylcyclopentadienyl Rhodium Catalyst", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: July 18, 2017; Published: September 1, 2017. \n\nThe authors thank Dr. Jay Winkler, Dr. Robert Nielsen, Dr. Sijia Dong, Dr. Davide Lionetti, Yufeng Huang, and Sydney Corona for numerous helpful discussions. This work was supported by the US National Science Foundation through the CCI Solar Fuels Program (CHE-1305124) and the Resnick Sustainability Institute at Caltech (fellowship to S.I.J.). J.D.B. was supported during preparation of this manuscript by an award from the State of Kansas through the University of Kansas New Faculty General Research Fund. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ic7b01698_si_001.pdf

Supplemental Material - ic7b01698_si_002.xyz

", "abstract": "Recent work has shown that Cp*Rh(bpy) [Cp* = pentamethylcyclopentadienyl, bpy = 2,2\u2032- bipyridine] undergoes endo protonation at the [Cp*] ligand in the presence of weak acid (Et_3NH^+; pK_a = 18.8 in MeCN). Upon exposure to stronger acid (e.g., DMFH+; pK_a = 6.1), hydrogen is evolved with unity yield. Here, we study the mechanisms by which this catalyst evolves dihydrogen using density functional theory (M06) with polarizable continuum solvation. The calculations show that the complex can be protonated by weak acid first at the metal center with a barrier of 3.2 kcal/mol; this proton then migrates to the ring to form the detected intermediate, a rhodium(I) compound bearing endo \u03b7^4-Cp*H. Stronger acid is required to evolve hydrogen, which calculations show happens via a concerted mechanism. The acid approaches and protonates the metal, while the second proton simultaneously migrates from the ring with a barrier of \u223c12 kcal/mol. Under strongly acidic conditions, we find that hydrogen evolution can proceed through a traditional metal\u2013hydride species; protonation of the initial hydride to form an H\u2013H bond occurs before migration of the hydride (in the form of a proton) to the [Cp*] ring (i.e., H\u2013H bond formation is faster than hydride\u2013proton tautomerization). This work demonstrates the role of acid strength in accessing different mechanisms of hydrogen evolution. Calculations also predict that modification of the bpy ligand by a variety of functional groups does not affect the preference for [Cp*] protonation, although the driving force for protonation changes. However, we predict that exchange of bpy for a bidentate phosphine ligand will stabilize a rhodium(III) hydride, reversing the preference for bound [Cp*H] found in all computed bpy derivatives and offering an appealing alternative ligand platform for future experimental and computational mechanistic studies of H_2 evolution.", "date": "2017-09-18", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "56", "number": "18", "publisher": "American Chemical Society", "pagerange": "11375-11386", "id_number": "CaltechAUTHORS:20170905-141449913", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170905-141449913", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "University of Kansas" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.7b01698", "primary_object": { "basename": "ic7b01698_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0fc0n-gva37/files/ic7b01698_si_001.pdf" }, "related_objects": [ { "basename": "ic7b01698_si_002.xyz", "url": "https://authors.library.caltech.edu/records/0fc0n-gva37/files/ic7b01698_si_002.xyz" } ], "pub_year": "2017", "author_list": "Johnson, Samantha I.; Gray, Harry B.; et al." }, { "id": "https://authors.library.caltech.edu/records/ppmkw-e0t15", "eprint_id": 77248, "eprint_status": "archive", "datestamp": "2023-08-21 21:42:09", "lastmod": "2023-10-25 22:00:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-S-J-R", "name": { "family": "Lee", "given": "Sebastian J. R." }, "orcid": "0000-0001-7006-9378" }, { "id": "Miyamoto-Kaito", "name": { "family": "Miyamoto", "given": "Kaito" } }, { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Density-based errors in mixed-basis mean-field electronic structure, with implications for embedding and QM/MM methods", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Mixed basis; Embedding; DFT; QM/MM; Embedded mean-field theory", "note": "\u00a9 2017 Published by Elsevier B.V. \n\nReceived 28 February 2017, Accepted 18 April 2017, Available online 19 April 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. The work was also supported by the U.S. Army Research Laboratory under Grant No. W911NF-12-2-0023. S.J.R.L. acknowledges a fellowship from the Caltech Resnick Institute, K.M. acknowledges financial support for his PhD research from Toyota Central R&D Labs, Inc., F.R.M. is grateful for financial support from the Engineering and Physical Sciences Research Council (EP/M013111/1), and T.F.M. acknowledges support from a Camille Dreyfus Teacher-Scholar Award.", "abstract": "We consider mean-field electronic structure calculations with subsystems that employ different atomic-orbital basis sets. A major source of error arises in charge-manifestation reactions (including ionization, electron attachment, or deprotonation) due to electronic density artifacts at the subsystem interface. The underlying errors in the electronic density can be largely eliminated with Fock-matrix corrections or by avoiding the use of a minimal basis set in the low-level region. These corrections succeed by balancing the electronegativity of atoms at the subsystem interface, much as link-atoms in QM/MM calculations rely upon balancing the electronegativity of atoms in the truncated QM region.", "date": "2017-09-01", "date_type": "published", "publication": "Chemical Physics Letters", "volume": "683", "publisher": "Elsevier", "pagerange": "375-382", "id_number": "CaltechAUTHORS:20170508-080116014", "issn": "0009-2614", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170508-080116014", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-12-2-0023" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Toyota Central R&D Labs, Inc." }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.cplett.2017.04.059", "pub_year": "2017", "author_list": "Lee, Sebastian J. R.; Miyamoto, Kaito; et al." }, { "id": "https://authors.library.caltech.edu/records/syh64-cbm50", "eprint_id": 78766, "eprint_status": "archive", "datestamp": "2023-08-19 04:37:24", "lastmod": "2023-10-26 00:22:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jhalani-V-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Ultrafast Hot Carrier Dynamics in GaN and its Impact on the Efficiency Droop", "ispublished": "pub", "full_text_status": "public", "keywords": "Gallium nitride, light emitting diodes, ultrafast dynamics, electron-phonon scattering", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: May 25, 2017; Revised: July 20, 2017; Published: July 24, 2017. \n\nV.J. thanks the Resnick Sustainibility Institute at Caltech for fellowship support. J.-J.Z. acknowledges support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of the computational methods employed in this work was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. M.B. acknowledges support by the National Science Foundation under Grant No. ACI-1642443, which provided for basic theory and part of the electronphonon coupling code development. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors thank Davide Sangalli for fruitful discussions. \n\nAuthor Contributions: M.B. conceived and designed the research. V.J. and J.-J.Z. developed the computational codes and carried out the calculations. All authors wrote the manuscript. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - acs.nanolett.7b02212_acc.pdf

Submitted - 1703.07880.pdf

Supplemental Material - nl7b02212_si_001.pdf

", "abstract": "GaN is a key material for lighting technology. Yet, the carrier transport and ultrafast dynamics that are central in GaN light-emitting devices are not completely understood. We present first-principles calculations of carrier dynamics in GaN, focusing on electron\u2013phonon (e-ph) scattering and the cooling and nanoscale dynamics of hot carriers. We find that e-ph scattering is significantly faster for holes compared to electrons and that for hot carriers with an initial 0.5\u20131 eV excess energy, holes take a significantly shorter time (\u223c0.1 ps) to relax to the band edge compared to electrons, which take \u223c1 ps. The asymmetry in the hot carrier dynamics is shown to originate from the valence band degeneracy, the heavier effective mass of holes compared to electrons, and the details of the coupling to different phonon modes in the valence and conduction bands. We show that the slow cooling of hot electrons and their long ballistic mean free paths (over 3 nm at room temperature) are a possible cause of efficiency droop in GaN light-emitting diodes. Taken together, our work sheds light on the ultrafast dynamics of hot carriers in GaN and the nanoscale origin of efficiency droop.", "date": "2017-08-09", "date_type": "published", "publication": "Nano Letters", "volume": "17", "number": "8", "publisher": "American Chemical Society", "pagerange": "5012-5019", "id_number": "CaltechAUTHORS:20170705-124137567", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170705-124137567", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.7b02212", "primary_object": { "basename": "1703.07880.pdf", "url": "https://authors.library.caltech.edu/records/syh64-cbm50/files/1703.07880.pdf" }, "related_objects": [ { "basename": "acs.nanolett.7b02212_acc.pdf", "url": "https://authors.library.caltech.edu/records/syh64-cbm50/files/acs.nanolett.7b02212_acc.pdf" }, { "basename": "nl7b02212_si_001.pdf", "url": "https://authors.library.caltech.edu/records/syh64-cbm50/files/nl7b02212_si_001.pdf" } ], "pub_year": "2017", "author_list": "Jhalani, Vatsal A.; Zhou, Jin-Jian; et al." }, { "id": "https://authors.library.caltech.edu/records/kr58y-vjv74", "eprint_id": 79124, "eprint_status": "archive", "datestamp": "2023-08-21 21:32:27", "lastmod": "2023-10-26 14:36:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Subhas-Adam-V", "name": { "family": "Subhas", "given": "Adam V." }, "orcid": "0000-0002-7688-6624" }, { "id": "Adkins-J-F", "name": { "family": "Adkins", "given": "Jess F." }, "orcid": "0000-0002-3174-5190" }, { "id": "Rollins-Nick-E", "name": { "family": "Rollins", "given": "Nick E." } }, { "id": "Naviaux-John-D", "name": { "family": "Naviaux", "given": "John" }, "orcid": "0000-0002-0681-3163" }, { "id": "Erez-Jonathan", "name": { "family": "Erez", "given": "Jonathan" }, "orcid": "0000-0003-4616-0176" }, { "id": "Berelson-William-M", "name": { "family": "Berelson", "given": "William M." }, "orcid": "0000-0002-1526-3802" } ] }, "title": "Catalysis and chemical mechanisms of calcite dissolution in seawater", "ispublished": "pub", "full_text_status": "public", "keywords": "mineral dissolution; isotope geochemistry; oceanography; catalysis", "note": "\u00a9 2017 National Academy of Sciences. \n\nEdited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved June 26, 2017 (received for review March 6, 2017). Published online before print July 18, 2017, doi: 10.1073/pnas.1703604114.\n\nWe acknowledge Alex Gagnon for helpful discussions on the formulation of the box model, and Yunbin Guan for help with SIMS analysis. We also thank Sijia Dong for discussions in general about carbonate dissolution in seawater. We thank Mathis Hain and one anonymous reviewer, whose careful reading and detailed comments greatly improved this manuscript. Thanks go to National Science Foundation Graduate Research Fellowship Program and the Resnick Institute Graduate Fellowships for supporting A.V.S. and J.N. We acknowledge support from NSF Grants OCE1220600 and OCE1220302. \n\nAuthor contributions: A.V.S., J.F.A., N.E.R., J.E., and W.M.B. designed research; A.V.S., N.E.R., and J.N. performed research; A.V.S., J.F.A., N.E.R., J.N., and W.M.B. analyzed data; and A.V.S., J.F.A., J.N., and W.M.B. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1703604114/-/DCSupplemental.\n\n

Published - PNAS-2017-Subhas-8175-80.pdf

Supplemental Material - pnas.1703604114.sapp.pdf

", "abstract": "Near-equilibrium calcite dissolution in seawater contributes significantly to the regulation of atmospheric CO_2 on 1,000-y timescales. Despite many studies on far-from-equilibrium dissolution, little is known about the detailed mechanisms responsible for calcite dissolution in seawater. In this paper, we dissolve ^(13)C-labeled calcites in natural seawater. We show that the time-evolving enrichment of \u03b4^(13)C in solution is a direct measure of both dissolution and precipitation reactions across a large range of saturation states. Secondary Ion Mass Spectrometer profiles into the ^(13)C-labeled solids confirm the presence of precipitated material even in undersaturated conditions. The close balance of precipitation and dissolution near equilibrium can alter the chemical composition of calcite deeper than one monolayer into the crystal. This balance of dissolution\u2013precipitation shifts significantly toward a dissolution-dominated mechanism below about \u03a9=\u20090.7. Finally, we show that the enzyme carbonic anhydrase (CA) increases the dissolution rate across all saturation states, and the effect is most pronounced close to equilibrium. This finding suggests that the rate of hydration of CO_2 is a rate-limiting step for calcite dissolution in seawater. We then interpret our dissolution data in a framework that incorporates both solution chemistry and geometric constraints on the calcite solid. Near equilibrium, this framework demonstrates a lowered free energy barrier at the solid\u2013solution interface in the presence of CA. This framework also indicates a significant change in dissolution mechanism at \u03a9=\u20090.7, which we interpret as the onset of homogeneous etch pit nucleation.", "date": "2017-08-01", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "31", "publisher": "National Academy of Sciences", "pagerange": "8175-8180", "id_number": "CaltechAUTHORS:20170717-093236411", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170717-093236411", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "OCE-1220600" }, { "agency": "NSF", "grant_number": "OCE-1220302" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1703604114", "pmcid": "PMC5547618", "primary_object": { "basename": "pnas.1703604114.sapp.pdf", "url": "https://authors.library.caltech.edu/records/kr58y-vjv74/files/pnas.1703604114.sapp.pdf" }, "related_objects": [ { "basename": "PNAS-2017-Subhas-8175-80.pdf", "url": "https://authors.library.caltech.edu/records/kr58y-vjv74/files/PNAS-2017-Subhas-8175-80.pdf" } ], "pub_year": "2017", "author_list": "Subhas, Adam V.; Adkins, Jess F.; et al." }, { "id": "https://authors.library.caltech.edu/records/ferfb-rxn21", "eprint_id": 78091, "eprint_status": "archive", "datestamp": "2023-08-19 04:13:06", "lastmod": "2023-10-25 23:44:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Jariwala-Deep", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Tat-Kevin", "name": { "family": "Tat", "given": "Kevin" } }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Sherrott-Michelle-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "High Photovoltaic Quantum Efficiency in Ultrathin van der Waals Heterostructures", "ispublished": "pub", "full_text_status": "public", "keywords": "van der Waals, heterojunction, photovoltaics, quantum efficiency, high efficiency, MoS2, WSe2", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: May 6, 2017; Accepted: June 2, 2017; Publication Date (Web): June 7, 2017. \n\nThis work is part of the \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under award no. DE-SC0001293. D.J., A.R.D., and M.C.S. acknowledge additional support from the Space Solar Power project and the Resnick Sustainability Institute Graduate and Postdoctoral Fellowships. A.R.D. also acknowledges support in part from the Kavli Nanoscience Institute Postdoctoral Fellowship. G.T. acknowledges support in part from the Swiss National Science Foundation, Early Postdoc Mobility Fellowship no. P2EZP2_159101. J.W. acknowledges support from the National Science Foundation Graduate Research Fellowship under grant no. 1144469. K.T. would like to thank the Caltech SURF program and the Northrop Grumman Corporation for financial support. \n\nAuthor Contributions: These authors contributed equally. J.W. and D.J. prepared the samples and fabricated the devices. J.W. and A. R. D. performed the calculations. J.W., D.J., and G.T. performed the measurements. K.T. and M.C.S. assisted with sample preparation and fabrication. H.A.A. supervised over all the experiments, calculations, and data collection. \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1706.02700.pdf

Supplemental Material - nn7b03148_si_001.pdf

", "abstract": "We report experimental measurements for ultrathin (<15 nm) van der Waals heterostructures exhibiting external quantum efficiencies exceeding 50% and show that these structures can achieve experimental absorbance >90%. By coupling electromagnetic simulations and experimental measurements, we show that pn Wse_2/MoS_2 heterojunctions with vertical carrier collection can have internal photocarrier collection efficiencies exceeding 70%.", "date": "2017-07-25", "date_type": "published", "publication": "ACS Nano", "volume": "11", "number": "7", "publisher": "American Chemical Society", "pagerange": "7230-7240", "id_number": "CaltechAUTHORS:20170612-090309097", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170612-090309097", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Space Solar Power Project" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "Northrop Grumman Corporation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "Space-Solar-Power-Project" } ] }, "doi": "10.1021/acsnano.7b03148", "primary_object": { "basename": "1706.02700.pdf", "url": "https://authors.library.caltech.edu/records/ferfb-rxn21/files/1706.02700.pdf" }, "related_objects": [ { "basename": "nn7b03148_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ferfb-rxn21/files/nn7b03148_si_001.pdf" } ], "pub_year": "2017", "author_list": "Wong, Joeson; Jariwala, Deep; et al." }, { "id": "https://authors.library.caltech.edu/records/sb7x9-22d61", "eprint_id": 76551, "eprint_status": "archive", "datestamp": "2023-08-19 03:48:28", "lastmod": "2023-10-25 16:06:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Prier-Christopher-K", "name": { "family": "Prier", "given": "Christopher K." }, "orcid": "0000-0003-0902-1636" }, { "id": "Zhang-Ruijie-K", "name": { "family": "Zhang", "given": "Ruijie K." }, "orcid": "0000-0002-7251-5527" }, { "id": "Buller-Andrew-R", "name": { "family": "Buller", "given": "Andrew R." }, "orcid": "0000-0002-9635-4844" }, { "id": "Brinkmann-Chen-Sabine", "name": { "family": "Brinkmann-Chen", "given": "Sabine" }, "orcid": "0000-0002-5419-4192" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Enantioselective, intermolecular benzylic C\u2013H amination catalysed by an engineered iron-haem enzyme", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Macmillan Publishers Limited. \n\nReceived 14 March 2017. Accepted 21 April 2017. Published online 29 May 2017. \n\nOur research is supported by the National Science Foundation, Division of Molecular and Cellular Biosciences (grant MCB-1513007) and by funds from the American Recovery and Reinvestment Act (ARRA) through the National Institutes of Health Shared Instrumentation Grant Program (S10RR027203). C.K.P. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. R.K.Z. was supported by a National Science Foundation Graduate Research Fellowship (NSF GRFP; DGE-1144469), is a trainee in the Caltech Biotechnology Leadership Program, and has received financial support from the Donna and Benjamin M. Rosen Bioengineering Center. A.R.B. is funded by a Ruth Kirschstein NIH Postdoctoral Fellowship F32G110851. We thank S.\u2009Virgil, J.\u2009Kaiser, and R.\u2009D. Lewis for experimental assistance, and O.\u2009F. Brandenberg, S.\u2009C. Hammer, and S.\u2009B.\u2009J.\u2009Kan for helpful discussion and comments on the manuscript. \n\nThese authors contributed equally to this work. Christopher K. Prier & Ruijie K. Zhang. \n\nAuthor ontributions: C.K.P. and R.K.Z. designed, carried out, and analysed all amination experiments, with F.H.A. providing guidance. C.K.P., R.K.Z. and S.B.-C. obtained protein crystals. R.K.Z. and A.R.B. solved the crystal structure. C.K.P. and F.H.A. wrote the manuscript with input from all of the authors. \n\nData availability: Complete experimental procedures, including synthesis methods for all compounds, characterization data, and details of bioconversion experiments are described in the Supplementary Information. The crystal structure of P411_(BM3) P-4 A82L A78V F263L has been deposited in the Protein Data Bank (PDB) under accession code 5UCW. \n\nThe authors declare no competing financial interests.\n\n

Accepted Version - nihms886928.pdf

Supplemental Material - nchem.2783-s1.pdf

", "abstract": "C\u2013H bonds are ubiquitous structural units of organic molecules. Although these bonds are generally considered to be chemically inert, the recent emergence of methods for C\u2013H functionalization promises to transform the way synthetic chemistry is performed. The intermolecular amination of C\u2013H bonds represents a particularly desirable and challenging transformation for which no efficient, highly selective, and renewable catalysts exist. Here we report the directed evolution of an iron-containing enzymatic catalyst\u2014based on a cytochrome P450 monooxygenase\u2014for the highly enantioselective intermolecular amination of benzylic C\u2013H bonds. The biocatalyst is capable of up to 1,300 turnovers, exhibits excellent enantioselectivities, and provides access to valuable benzylic amines. Iron complexes are generally poor catalysts for C\u2013H amination: in this catalyst, the enzyme's protein framework confers activity on an otherwise unreactive iron-haem cofactor.", "date": "2017-07", "date_type": "published", "publication": "Nature Chemistry", "volume": "9", "number": "7", "publisher": "Nature Publishing Group", "pagerange": "629-634", "id_number": "CaltechAUTHORS:20170413-120718900", "issn": "1755-4330", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170413-120718900", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "American Recovery and Reinvestment Act (ARRA)" }, { "agency": "NIH", "grant_number": "S10RR027203" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Donna and Benjamin M. Rosen Bioengineering Center" }, { "agency": "NIH Postdoctoral Fellowship", "grant_number": "F32G110851" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Rosen-Bioengineering-Center" } ] }, "doi": "10.1038/nchem.2783", "pmcid": "PMC5555633", "primary_object": { "basename": "nchem.2783-s1.pdf", "url": "https://authors.library.caltech.edu/records/sb7x9-22d61/files/nchem.2783-s1.pdf" }, "related_objects": [ { "basename": "nihms886928.pdf", "url": "https://authors.library.caltech.edu/records/sb7x9-22d61/files/nihms886928.pdf" } ], "pub_year": "2017", "author_list": "Prier, Christopher K.; Zhang, Ruijie K.; et al." }, { "id": "https://authors.library.caltech.edu/records/x7bz5-ykq80", "eprint_id": 77691, "eprint_status": "archive", "datestamp": "2023-08-21 21:20:18", "lastmod": "2023-10-25 23:21:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liberman-Martin-A-L", "name": { "family": "Liberman-Martin", "given": "Allegra L." }, "orcid": "0000-0002-8447-905X" }, { "id": "Chu-Crystal-K", "name": { "family": "Chu", "given": "Crystal K." }, "orcid": "0000-0002-7783-2564" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Application of Bottlebrush Block Copolymers as Photonic Crystals", "ispublished": "pub", "full_text_status": "restricted", "keywords": "photonic crystals; bottlebrush; block copolymers; self-assembly; structural color", "note": "\u00a9 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived: January 25, 2017; Revised: April 8, 2017;\nPublished online: May 22, 2017.\n\nWe would like to acknowledge the many co-workers over the years who have contributed to the research described above. The U.S. National Science Foundation (CHE-1048404), U.S. Department of Energy (DE-SC0001293), and a Dow Resnick Bridge Award funded aspects of our research in this area. A.L.L.-M. thanks the Resnick Sustainability Institute at Caltech for fellowship support. We thank Alice B. Chang for insightful discussions during the preparation of this manuscript.", "abstract": "Brush block copolymers are a class of comb polymers that feature polymeric side chains densely grafted to a linear backbone. These polymers display interesting properties due to their dense functionality, low entanglement, and ability to rapidly self-assemble to highly ordered nanostructures. The ability to prepare brush polymers with precise structures has been enabled by advancements in controlled polymerization techniques. This Feature Article highlights the development of brush block copolymers as photonic crystals that can reflect visible to near-infrared wavelengths of light. Fabrication of these materials relies on polymer self-assembly processes to achieve nanoscale ordering, which allows for the rapid preparation of photonic crystals from common organic chemical feedstocks. The characteristic physical properties of brush block copolymers are discussed, along with methods for their preparation. Strategies to induce self-assembly at ambient temperatures and the use of blending techniques to tune photonic properties are emphasized.", "date": "2017-07", "date_type": "published", "publication": "Macromolecular Rapid Communications", "volume": "38", "number": "13", "publisher": "Wiley", "pagerange": "Art. No. 1700058", "id_number": "CaltechAUTHORS:20170524-075636935", "issn": "1022-1336", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170524-075636935", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1048404" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Dow Chemical Company" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/marc.201700058", "pub_year": "2017", "author_list": "Liberman-Martin, Allegra L.; Chu, Crystal K.; et al." }, { "id": "https://authors.library.caltech.edu/records/1n6bk-mr162", "eprint_id": 78131, "eprint_status": "archive", "datestamp": "2023-08-19 03:45:43", "lastmod": "2023-10-25 23:47:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lieblich-S-A", "name": { "family": "Lieblich", "given": "Seth A." }, "orcid": "0000-0003-2705-5821" }, { "id": "Fang-Katharine-Y", "name": { "family": "Fang", "given": "Katharine Y." } }, { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." } }, { "id": "Rawson-Jeffrey", "name": { "family": "Rawson", "given": "Jeffrey" } }, { "id": "LeBon-Jeanne-M", "name": { "family": "LeBon", "given": "Jeanne" } }, { "id": "Ku-Hsun-Teresa", "name": { "family": "Ku", "given": "H. Teresa" } }, { "id": "Tirrell-D-A", "name": { "family": "Tirrell", "given": "David A." }, "orcid": "0000-0003-3175-4596" } ] }, "title": "4S-Hydroxylation of insulin at ProB28 accelerates hexamer dissociation and delays fibrillation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: January 24, 2017. Published: June 9, 2017. \n\nWe thank J. T. Kaiser, P. Nikolovski, S. Russi, S. Virgil, M. Shahgholi, A. Lakshmanan, and the scientific staff of Beamline 12-2 at the Stanford Synchrotron Radiation Laboratory for assistance. We thank W. Glenn, A. Mahdavi, and T. Hoeg-Jensen for discussions. The work was supported by the Novo Nordisk Foundation. Fellowships from Amgen and from the Natural Sciences and Engineering Research Council of Canada (NSERC, PGS-D) provided partial support for S.A.L. and K.Y.F., respectively. J.K.B.C. acknowledges support of the Resnick Sustainability Institute (Caltech). \n\nThe authors declare the following competing financial interest(s): S.A.L., K.Y.F., and D.A.T are inventors on a related patent application.\n\n

Accepted Version - jacs_2E7b00794.pdf

Accepted Version - nihms932453.pdf

Supplemental Material - ja7b00794_si_001.pdf

", "abstract": "Daily injections of insulin provide lifesaving benefits to millions of diabetics. But currently available prandial insulins are suboptimal: The onset of action is delayed by slow dissociation of the insulin hexamer in the subcutaneous space, and insulin forms amyloid fibrils upon storage in solution. Here we show, through the use of non-canonical amino acid mutagenesis, that replacement of the proline residue at position 28 of the insulin B-chain (ProB28) by (4S)-hydroxyproline (Hzp) yields an active form of insulin that dissociates more rapidly, and fibrillates more slowly, than the wild-type protein. Crystal structures of dimeric and hexameric insulin preparations suggest that a hydrogen bond between the hydroxyl group of Hzp and a backbone amide carbonyl positioned across the dimer interface may be responsible for the altered behavior. The effects of hydroxylation are stereospecific; replacement of ProB28 by (4R)-hydroxyproline (Hyp) causes little change in the rates of fibrillation and hexamer disassociation. These results demonstrate a new approach that fuses the concepts of medicinal chemistry and protein design, and paves the way to further engineering of insulin and other therapeutic proteins.", "date": "2017-06-28", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "25", "publisher": "American Chemical Society", "pagerange": "8384-8387", "id_number": "CaltechAUTHORS:20170612-160413860", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170612-160413860", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Novo Nordisk Foundation" }, { "agency": "Amgen" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.7b00794", "pmcid": "PMC5812673", "primary_object": { "basename": "nihms932453.pdf", "url": "https://authors.library.caltech.edu/records/1n6bk-mr162/files/nihms932453.pdf" }, "related_objects": [ { "basename": "ja7b00794_si_001.pdf", "url": "https://authors.library.caltech.edu/records/1n6bk-mr162/files/ja7b00794_si_001.pdf" }, { "basename": "jacs_2E7b00794.pdf", "url": "https://authors.library.caltech.edu/records/1n6bk-mr162/files/jacs_2E7b00794.pdf" } ], "pub_year": "2017", "author_list": "Lieblich, Seth A.; Fang, Katharine Y.; et al." }, { "id": "https://authors.library.caltech.edu/records/xqe4r-g7n57", "eprint_id": 78146, "eprint_status": "archive", "datestamp": "2023-08-21 21:17:27", "lastmod": "2025-04-25 22:48:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A." }, "orcid": "0000-0003-0097-5716" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" } ] }, "title": "Cu metal embedded in oxidized matrix catalyst to promote CO\u2082 activation and CO dimerization for electrochemical reduction of CO\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "electrochemical reduction of CO\u2082; Cu metal embedded in oxidized matrix; density functional theory; CO\u2082 activation; CO dimerization", "note": "\u00a9 2017 National Academy of Sciences. Freely available online through the PNAS open access option. \n\nContributed by William A. Goddard III, May 9, 2017 (sent for review February 13, 2017; reviewed by Timo Jacob and Bruce Parkinson). \n\nThis research was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993. This work used the computational resources of Zwicky (at California Institute of Technology). \n\nAuthor contributions: H.X. and W.A.G. designed research; H.X. and T.C. performed research; H.X., W.A.G., T.C., and Y.L. analyzed data; and H.X. and W.A.G. wrote the paper. \n\nReviewers: T.J., Universit\u00e4t Ulm; and B.P., University of Wyoming. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1702405114/-/DCSupplemental.\n\n

Published - PNAS-2017-Xiao-6685-8.pdf

Supplemental Material - pnas.201702405SI.pdf

", "abstract": "We propose and validate with quantum mechanics methods a unique catalyst for electrochemical reduction of CO\u2082 (CO\u2082RR) in which selectivity and activity of CO and C\u2082 products are both enhanced at the borders of oxidized and metallic surface regions. This Cu metal embedded in oxidized matrix (MEOM) catalyst is consistent with observations that Cu\u2082O-based electrodes improve performance. However, we show that a fully oxidized matrix (FOM) model would not explain the experimentally observed performance boost, and we show that the FOM is not stable under CO\u2082 reduction conditions. This electrostatic tension between the Cu\u207a and Cu\u2070 surface sites responsible for the MEOM mechanism suggests a unique strategy for designing more efficient and selective electrocatalysts for CO\u2082RR to valuable chemicals (HCO\u2093), a critical need for practical environmental and energy applications.", "date": "2017-06-27", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "26", "publisher": "National Academy of Sciences", "pagerange": "6685-6688", "id_number": "CaltechAUTHORS:20170613-083147382", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170613-083147382", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.1702405114", "pmcid": "PMC5495255", "primary_object": { "basename": "pnas.201702405SI.pdf", "url": "https://authors.library.caltech.edu/records/xqe4r-g7n57/files/pnas.201702405SI.pdf" }, "related_objects": [ { "basename": "PNAS-2017-Xiao-6685-8.pdf", "url": "https://authors.library.caltech.edu/records/xqe4r-g7n57/files/PNAS-2017-Xiao-6685-8.pdf" } ], "pub_year": "2017", "author_list": "Xiao, Hai; Goddard, William A.; et al." }, { "id": "https://authors.library.caltech.edu/records/h5qc1-1gz95", "eprint_id": 78321, "eprint_status": "archive", "datestamp": "2023-08-19 03:41:30", "lastmod": "2023-10-26 00:00:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jasper-J-T", "name": { "family": "Jasper", "given": "Justin T." }, "orcid": "0000-0002-2461-5283" }, { "id": "Yang-Yang-ENVENG", "name": { "family": "Yang", "given": "Yang" }, "orcid": "0000-0003-3767-8029" }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" } ] }, "title": "Toxic Byproduct Formation during Electrochemical Treatment of Latrine Wastewater", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. ACS AuthorChoice - This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. \n\nReceived: March 23, 2017; Revised: May 22, 2017; Accepted: May 24, 2017; Published: May 24, 2017. \n\nThis research was supported by the Bill and Melinda Gates Foundation (BMGF RTTC Grants OPP1111246 and OPP1149755) and a Resnick Postdoctoral Fellowship to J.T.J. We thank James Queen and Harry Collini for help with sample analysis. We also thank James Barazesh, Eric Huang, and Cody Finke for helpful discussion and critically reviewing the manuscript.\n\n

Published - acs.est.7b01002.pdf

Supplemental Material - es7b01002_si_001.pdf

", "abstract": "Electrochemical systems are an attractive option for onsite latrine wastewater treatment due to their high efficiency and small footprint. While concerns remain over formation of toxic byproducts during treatment, rigorous studies examining byproduct formation are lacking. Experiments treating authentic latrine wastewater over variable treatment times, current densities, chloride concentrations, and anode materials were conducted to characterize byproducts and identify conditions that minimize their formation. Production of inorganic byproducts (chlorate and perchlorate) and indicator organic byproducts (haloacetic acids and trihalomethanes) during electrolysis dramatically exceeded recommendations for drinking water after one treatment cycle (\u223c10\u201330\u202f000 times), raising concerns for contamination of downstream water supplies. Stopping the reaction after ammonium was removed (i.e., the chlorination breakpoint) was a promising method to minimize byproduct formation without compromising disinfection and nutrient removal. Though treatment was accelerated at increased chloride concentrations and current densities, byproduct concentrations remained similar near the breakpoint. On TiO_2/IrO_2 anodes, haloacetic acids (up to \u223c50 \u03bcM) and chlorate (up to \u223c2 \u03bcM) were of most concern. Although boron-doped diamond anodes mineralized haloacetic acids after formation, high production rates of chlorate and perchlorate (up to \u223c4 and 25 \u03bcM) made them inferior to TiO_2/IrO_2 anodes in terms of toxic byproduct formation. Organic byproduct formation was similar during chemical chlorination and electrolysis of wastewater, suggesting that organic byproducts are formed by similar pathways in both cases (i.e., reactions with chloramines and free chlorine).", "date": "2017-06-20", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "51", "number": "12", "publisher": "American Chemical Society", "pagerange": "7111-7119", "id_number": "CaltechAUTHORS:20170619-084556145", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170619-084556145", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1111246" }, { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1149755" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.est.7b01002", "pmcid": "PMC5480235", "primary_object": { "basename": "acs.est.7b01002.pdf", "url": "https://authors.library.caltech.edu/records/h5qc1-1gz95/files/acs.est.7b01002.pdf" }, "related_objects": [ { "basename": "es7b01002_si_001.pdf", "url": "https://authors.library.caltech.edu/records/h5qc1-1gz95/files/es7b01002_si_001.pdf" } ], "pub_year": "2017", "author_list": "Jasper, Justin T.; Yang, Yang; et al." }, { "id": "https://authors.library.caltech.edu/records/xxg4n-s3t67", "eprint_id": 76533, "eprint_status": "archive", "datestamp": "2023-08-19 03:41:02", "lastmod": "2025-04-26 03:15:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abidi-I-H", "name": { "family": "Abidi", "given": "Irfan H." } }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Pan-Jie", "name": { "family": "Pan", "given": "Jie" } }, { "id": "Tyagi-Abhishek", "name": { "family": "Tyagi", "given": "Abhishek" } }, { "id": "Zhuang-Minghao", "name": { "family": "Zhuang", "given": "Minghao" } }, { "id": "Zhang-Qicheng", "name": { "family": "Zhang", "given": "Qicheng" }, "orcid": "0000-0002-6702-191X" }, { "id": "Cagang-A-A", "name": { "family": "Cagang", "given": "Aldrine A." } }, { "id": "Weng-Lu-Tao", "name": { "family": "Weng", "given": "Lu-Tao" } }, { "id": "Sheng-Ping", "name": { "family": "Sheng", "given": "Ping" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Luo-Zhengtang", "name": { "family": "Luo", "given": "Zhengtang" } } ] }, "title": "Regulating Top-Surface Multilayer/Single-Crystal Graphene Growth by \"Gettering\" Carbon Diffusion at Backside of the Copper Foil", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon gettering, CVD graphene, multilayers, nucleation, single crystals", "note": "\u00a9 2017 Wiley-VCH Verlag GmbH & Co. \n\nVersion of Record online: 11 Apr 2017. Manuscript Revised: 13 Feb 2017. Manuscript Received: 9 Jan 2017. \n\nThis project was supported by the Research Grant Council of Hong Kong SAR (Project number 16204815). The authors appreciate the support from the Center for 1D/2D Quantum Materials and the Innovation and Technology Commission (ITC-CNERC14SC01). I.H.A. appreciates financial support from the Higher Education Commission (HEC) of Pakistan. Technical assistance from the Materials Characterization and Preparation Facilities is greatly appreciated. Y.L. thanks the support from the Resnick Prize Postdoctoral Fellowship at the Caltech. W.A.G. III thanks the NSF (DMREF-1436985) and the DOE (DE-SC0014607) for support. This work used computational resources provided by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract DE-AC02-05CH11231, the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by the NSF Grant ACI-1053575, and of the National Renewable Energy Laboratory supported by the DoE office of Energy Efficiency and Renewable Energy.\n\n

Accepted Version - RegulatingGraphene_Growth_Gettering-final.pdf

Supplemental Material - adfm201700121-sup-0001-S1.pdf

", "abstract": "A unique strategy is reported to constrain the nucleation centers for multilayer graphene (MLG) and, later, single-crystal graphene domains by gettering carbon source on backside of the flat Cu foil, during chemical vapor deposition. Hitherto, for a flat Cu foil, the top-surface-based growth mechanism is emphasized, while overlooking the graphene on the backside. However, the systematic experimental findings indicate a strong correlation between the backside graphene and the nucleation centers on the top-surface, governed by the carbon diffusion through the bulk Cu. This understanding steers to devise a strategy to mitigate the carbon diffusion to the top-surface by using a carbon \"getter\" substrate, such as nickel, on the backside of the Cu foil. Depth profiling of the nickel substrate, along with the density functional theory calculations, verifies the gettering role of the nickel support. The implementation of the backside carbon gettering approach on single-crystal graphene growth results in lowering the nucleation density by two orders of magnitude. This enables the single-crystal domains to grow by 6 mm laterally on the untreated Cu foil. Finally, the growth of large-area polycrystalline single layer graphene, free of unwanted MLG domains, with significantly improved field-effect mobility of \u22486800 cm^2 V^(\u22121) s^(\u22121) is demonstrated.", "date": "2017-06-20", "date_type": "published", "publication": "Advanced Functional Materials", "volume": "27", "number": "23", "publisher": "Wiley", "pagerange": "Art. No. 1700121", "id_number": "CaltechAUTHORS:20170412-093637154", "issn": "1616-301X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170412-093637154", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Research Grants Council of Hong Kong", "grant_number": "16204815" }, { "agency": "Innovation and Technology Commission (Hong Kong)", "grant_number": "ITC-CNERC14SC01" }, { "agency": "Higher Education Commission (Pakistan)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1436985" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014607" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "other_numbering_system": { "items": [ { "id": "1214", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/adfm.201700121", "primary_object": { "basename": "adfm201700121-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/xxg4n-s3t67/files/adfm201700121-sup-0001-S1.pdf" }, "related_objects": [ { "basename": "RegulatingGraphene_Growth_Gettering-final.pdf", "url": "https://authors.library.caltech.edu/records/xxg4n-s3t67/files/RegulatingGraphene_Growth_Gettering-final.pdf" } ], "pub_year": "2017", "author_list": "Abidi, Irfan H.; Liu, Yuanyue; et al." }, { "id": "https://authors.library.caltech.edu/records/92pyz-35h58", "eprint_id": 77648, "eprint_status": "archive", "datestamp": "2023-08-19 03:38:22", "lastmod": "2025-04-23 19:51:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Wei-Hsiang", "name": { "family": "Lin", "given": "Wei-Hsiang" }, "orcid": "0000-0003-0037-1277" }, { "id": "Brar-V-W", "name": { "family": "Brar", "given": "Victor W." } }, { "id": "Jariwala-D", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Sherrott-M-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Tseng-Wei-Shiuan", "name": { "family": "Tseng", "given": "Wei-Shiuan" } }, { "id": "Wu-Chih-I", "name": { "family": "Wu", "given": "Chih-I" } }, { "id": "Yeh-Nai-Chang", "name": { "family": "Yeh", "given": "Nai-Chang" }, "orcid": "0000-0002-1826-419X" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Atomic-scale Structural and Chemical Characterization of Hexagonal Boron Nitride Layers Synthesized at the Wafer-Scale with Monolayer Thickness Control", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: January 15, 2017; Revised: May 21, 2017; Published: May 22, 2017. \n\nThe authors gratefully acknowledge support from the Department of Energy, Office of Science under Grant DE-FG02-07ER46405 (W.H.L. and H.A.A.) and for use of facilities of the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (DE-SC0001293). D.J. and M.C.S. acknowledge additional support from Resnick Sustainability Institute Graduate and Postdoctoral Fellowships whereas V.W.B. acknowledge additional support from the Kavli Nanoscience Postdoctoral Fellowship. The authors thank Prof. George Rossman for access to the Raman and FTIR tools. The authors thank I-Te Lu for the discussion about the moir\u00e9 pattern calculation. The authors acknowledge support from the Beckman Institute of the California Institute of Technology to the Molecular Materials Research Center. \n\nThe authors declare no competing financial interests.\n\n

Accepted Version - acs_2Echemmater_2E7b00183.pdf

Submitted - 1705.07970.pdf

Supplemental Material - cm7b00183_si_001.pdf

", "abstract": "Hexagonal boron nitride (h-BN) is a promising two-dimensional insulator with a large band gap and low density of charged impurities that is isostructural and isoelectronic with graphene. Here we report the chemical and atomic-scale structure of CVD-grown wafer-scale (\u223c25 cm^2) h-BN sheets ranging in thickness from 1 to 20 monolayers. Atomic-scale images of h-BN on Au and graphene/Au substrates obtained by scanning tunneling microscopy reveal high h-BN crystalline quality in monolayer samples. Further characterization of 1\u201320 monolayer samples indicates uniform thickness for wafer-scale areas; this thickness control is a result of precise control of the precursor flow rate, deposition temperature and pressure. Raman and infrared spectroscopy indicate the presence of B\u2013N bonds and reveal a linear dependence of thickness with growth time. X-ray photoelectron spectroscopy shows the film stoichiometry, and the B/N atom ratio in our films is 1 \u00b1 0.6% across the range of thicknesses. Electrical current transport in metal/insulator/metal (Au/h-BN/Au) heterostructures indicates that our CVD-grown h-BN films can act as excellent tunnel barriers with a high hard-breakdown field strength. Our results suggest that large-area h-BN films are structurally, chemically and electronically uniform over the wafer scale, opening the door to pervasive application as a dielectric in layered nanoelectronic and nanophotonic heterostructures.", "date": "2017-06-13", "date_type": "published", "publication": "Chemistry of Materials", "volume": "29", "number": "11", "publisher": "American Chemical Society", "pagerange": "4700-4707", "id_number": "CaltechAUTHORS:20170523-090321139", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170523-090321139", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acs.chemmater.7b00183", "primary_object": { "basename": "cm7b00183_si_001.pdf", "url": "https://authors.library.caltech.edu/records/92pyz-35h58/files/cm7b00183_si_001.pdf" }, "related_objects": [ { "basename": "1705.07970.pdf", "url": "https://authors.library.caltech.edu/records/92pyz-35h58/files/1705.07970.pdf" }, { "basename": "acs_2Echemmater_2E7b00183.pdf", "url": "https://authors.library.caltech.edu/records/92pyz-35h58/files/acs_2Echemmater_2E7b00183.pdf" } ], "pub_year": "2017", "author_list": "Lin, Wei-Hsiang; Brar, Victor W.; et al." }, { "id": "https://authors.library.caltech.edu/records/yvrq4-6ez26", "eprint_id": 77809, "eprint_status": "archive", "datestamp": "2023-08-19 03:32:53", "lastmod": "2025-04-26 03:15:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Haiqing", "name": { "family": "Zhou", "given": "Haiqing" } }, { "id": "Yu-Fang", "name": { "family": "Yu", "given": "Fang" } }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Sun-Jingying", "name": { "family": "Sun", "given": "Jingying" } }, { "id": "Zhu-Zhuan", "name": { "family": "Zhu", "given": "Zhuan" } }, { "id": "He-Ran", "name": { "family": "He", "given": "Ran" } }, { "id": "Bao-Jiming", "name": { "family": "Bao", "given": "Jiming" }, "orcid": "0000-0002-6819-0117" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Chen-Shuo", "name": { "family": "Chen", "given": "Shuo" } }, { "id": "Ren-Zhifeng", "name": { "family": "Ren", "given": "Zhifeng" }, "orcid": "0000-0001-8233-3332" } ] }, "title": "Outstanding hydrogen evolution reaction catalyzed by porous nickel diselenide electrocatalysts", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 The Royal Society of Chemistry. \n\nReceived 22nd March 2017; Accepted 17th May 2017; First published on 17th May 2017. \n\nThis project was mainly funded by the US Defense Threat Reduction Agency (DTRA) under grant FA 7000-13-1-0001, and the US Department of Energy under a grant DE-SC0010831. J. S. and S. C. also acknowledge the support from TcSUH as the TcSUH Robert A. Welch Professorships in High Temperature Superconducting (HTSg) and Chemical Materials (E-0001). Y. L. acknowledges the support from Resnick Prize Postdoctoral Fellowship at Caltech. W. A. G. and Y. L. acknowledge support from NSF (CBET 1512759). The calculations were performed on PEREGRINE (NREL), XSEDE (NSF ACI-1053575), and NERSC (DOE DE-AC02-05CH11231). J. M. B. acknowledges the support from the National Science Foundation (CAREER Award ECCS-1240510) and the Robert A. Welch Foundation (E-1728).\n\n

Supplemental Material - c7ee00802c1_si.pdf

", "abstract": "To relieve our strong reliance on fossil fuels and to reduce greenhouse effects, there is an ever-growing interest in using electrocatalytic water splitting to produce green, renewable, and environment-benign hydrogen fuel via the hydrogen evolution reaction. For commercially feasible water electrolysis, it is imperative to develop electrocatalysts that perform as efficiently as Pt but using only earth-abundant commercial materials. However, the highest performance current catalysts consist of nanostructures made by using complex methods. Here we report a porous nickel diselenide (NiSe_2) catalyst that is superior for water electrolysis, exhibiting much better catalytic performance than most first-row transition metal dichalcogenide-based catalysts, well-studied MoS_2, and WS_2-based catalysts. Indeed NiSe2 performs comparably to the state-of-the-art Pt catalysts. We fabricate NiSe_2 directly from commercial nickel foam by acetic acid-assisted surface roughness engineering. To understand the origin of the high performance, we use first-principles calculations to identify the active sites. This work demonstrates the commercial possibility of hydrogen production via water electrolysis using porous bulk NiSe_2 catalysts.", "date": "2017-06-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "10", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1487-1492", "id_number": "CaltechAUTHORS:20170526-101433912", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170526-101433912", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Threat Reduction Agency (DTRA)", "grant_number": "FA 7000-13-1-0001" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0010831" }, { "agency": "Texas Center for Superconductivity" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ECCS-1240510" }, { "agency": "Robert A. Welch Foundation", "grant_number": "E-1728" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c7ee00802c", "primary_object": { "basename": "c7ee00802c1_si.pdf", "url": "https://authors.library.caltech.edu/records/yvrq4-6ez26/files/c7ee00802c1_si.pdf" }, "pub_year": "2017", "author_list": "Zhou, Haiqing; Yu, Fang; et al." }, { "id": "https://authors.library.caltech.edu/records/zw8es-k3x19", "eprint_id": 77792, "eprint_status": "archive", "datestamp": "2023-08-21 21:11:20", "lastmod": "2023-10-25 23:27:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ning-Xin", "name": { "family": "Ning", "given": "Xin" }, "orcid": "0000-0002-9432-3665" }, { "id": "Pellegrino-S", "name": { "family": "Pellegrino", "given": "Sergio" }, "orcid": "0000-0001-9373-3278" } ] }, "title": "Experiments on imperfection insensitive axially loaded cylindrical shells", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Wavy shell; Imperfection; Compression test", "note": "\u00a9 2017 Elsevier Ltd. \n\nReceived 4 August 2015, Revised 1 May 2016, Accepted 28 February 2017, Available online 15 March 2017. \n\nWe thank Professors P. Ermanni and M.M. Mikulas for help and advice during the course of this study. J. Steeves provided the lamina properties in Section 2.2 and the fiber misalignment data in Section 4.6.1. We thank R. Hurley and Professor J. Andrade for providing access to the high-speed camera. We also thank P. Arakelian, I. Maqueda, and K. Patterson for help and advice regarding shell manufacturing and testing. Financial support from the Resnick Institute at the California Institute of Technology is gratefully acknowledged.", "abstract": "This paper presents an experimental study of imperfection insensitive composite wavy cylindrical shells subject to axial compression. A fabrication technique for making cylindrical shells with intricate shape of cross-sections has been developed. A photogrammetry technique to measure the geometric imperfections has also been developed. The behavior of the wavy shells under axial compression was predicted through simulations and measured through compression tests. Both the analyses and experiments have confirmed that the wavy shells are imperfection insensitive. Comparisons between the wavy shells and circular shells have also confirmed that introducing optimal symmetry-breaking wavy cross-sections can significantly reduce the imperfection sensitivity and improve the load-bearing capability of cylindrical shells.", "date": "2017-06-01", "date_type": "published", "publication": "International Journal of Solids and Structures", "volume": "115-116", "publisher": "Elsevier", "pagerange": "73-86", "id_number": "CaltechAUTHORS:20170526-080151216", "issn": "0020-7683", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170526-080151216", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1016/j.ijsolstr.2017.02.028", "pub_year": "2017", "author_list": "Ning, Xin and Pellegrino, Sergio" }, { "id": "https://authors.library.caltech.edu/records/e40wa-gyv79", "eprint_id": 76553, "eprint_status": "archive", "datestamp": "2023-08-19 03:13:47", "lastmod": "2023-10-25 16:06:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Wen-Bo", "name": { "family": "Liu", "given": "Wen-Bo" }, "orcid": "0000-0003-2687-557X" }, { "id": "Schuman-D-P", "name": { "family": "Schuman", "given": "David P." } }, { "id": "Yang-Yun-Fang", "name": { "family": "Yang", "given": "Yun-Fang" }, "orcid": "0000-0002-6287-1640" }, { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Liang-Yong", "name": { "family": "Liang", "given": "Yong" }, "orcid": "0000-0002-7225-7062" }, { "id": "Klare-H-F-T", "name": { "family": "Klare", "given": "Hendrik F. T." }, "orcid": "0000-0003-3748-6609" }, { "id": "Nesnas-N", "name": { "family": "Nesnas", "given": "Nasri" }, "orcid": "0000-0003-3511-940X" }, { "id": "Oestreich-M", "name": { "family": "Oestreich", "given": "Martin" }, "orcid": "0000-0002-1487-9218" }, { "id": "Blackmond-D-G", "name": { "family": "Blackmond", "given": "Donna G." }, "orcid": "0000-0001-9829-8375" }, { "id": "Virgil-S-C", "name": { "family": "Virgil", "given": "Scott C." }, "orcid": "0000-0001-8586-5641" }, { "id": "Banerjee-Shibdas", "name": { "family": "Banerjee", "given": "Shibdas" }, "orcid": "0000-0002-3424-8157" }, { "id": "Zare-R-N", "name": { "family": "Zare", "given": "Richard N." }, "orcid": "0000-0001-5266-4253" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" }, { "id": "Houk-K-N", "name": { "family": "Houk", "given": "K. N." }, "orcid": "0000-0002-8387-5261" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Potassium tert-Butoxide-Catalyzed Dehydrogenative C\u2013H Silylation of Heteroaromatics: A Combined Experimental and Computational Mechanistic Study", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived 19 December 2016. Published online 12 April 2017. \n\nThe authors wish to thank the NSF under the CCI Center for Selective C\u2013H Functionalization (CCHF) (CHE-1205646), CHE-\n1212767 for support, the Novartis Institutes for Biomedical Research Incorporated for the donation of samples to the CCHF, and CHE-1361104. Calculations were performed on the Hoffman2 cluster at UCLA and the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by the NSF. The Shanghai Institute of Organic Chemistry (SIOC) and S.-L. You are thanked for a postdoctoral fellowship to W.-B.L. D.P.S. thanks the CCI Center for Selective C\u2013H Functionalization for support and the Blackmond group (TSRI) for their assistance and hospitality. A.A.T. is grateful to Bristol-Myers Squibb, the Resnick Sustainability Institute at Caltech, and to Dow Chemical for predoctoral fellowship as well as to NSERC for a PGS D fellowship. M.O. is indebted to the Einstein Foundation (Berlin) for an endowed professorship. N.N. thanks Florida Tech for sabbatical leave and thanks B.M.S. and Caltech for hosting him in their research labs. We thank J. Buss (Caltech), N. Thompson (Caltech), Prof. Krenske (University of Queensland), and Prof. Jenkins (Griffith Univ.) for helpful discussions. The Peters, Bercaw, and Agapie groups (Caltech) are thanked for instrumentation. We thank Dr. Angelo Di Bilio for assistance in recording EPR spectra, Dr. Dave VanderVelde for NMR expertise, and Dr. Mona Shahgholi and Dr. Naseem Torian for mass spectrometry assistance (Caltech). We thank Claude Y. Legault for CYLView, used for the molecular graphics. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - jacs_2E6b13031.pdf

Supplemental Material - ja6b13031_si_001.pdf

", "abstract": "We recently reported a new method for the direct dehydrogenative C\u2013H silylation of heteroaromatics utilizing Earth-abundant potassium tert-butoxide. Herein we report a systematic experimental and computational mechanistic investigation of this transformation. Our experimental results are consistent with a radical chain mechanism. A trialkylsilyl radical may be initially generated by homolytic cleavage of a weakened Si\u2013H bond of a hypercoordinated silicon species as detected by IR, or by traces of oxygen which can generate a reactive peroxide by reaction with (KOt-Bu)_4 as indicated by density functional theory (DFT) calculations. Radical clock and kinetic isotope experiments support a mechanism in which the C\u2013Si bond is formed through silyl radical addition to the heterocycle followed by subsequent \u03b2-hydrogen scission. DFT calculations reveal a reasonable energy profile for a radical mechanism and support the experimentally observed regioselectivity. The silylation reaction is shown to be reversible, with an equilibrium favoring products due to the generation of H_2 gas. In situ NMR experiments with deuterated substrates show that H_2 is formed by a cross-dehydrogenative mechanism. The stereochemical course at the silicon center was investigated utilizing a ^2H-labeled silolane probe; complete scrambling at the silicon center was observed, consistent with a number of possible radical intermediates or hypercoordinate silicates.", "date": "2017-05-24", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "20", "publisher": "American Chemical Society", "pagerange": "6867-6879", "id_number": "CaltechAUTHORS:20170413-121146154", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170413-121146154", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "NSF", "grant_number": "CHE-1361104" }, { "agency": "Shangai Institute of Organic Chemistry" }, { "agency": "Bristol-Myers Squibb" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Einstein Foundation Berlin" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.6b13031", "primary_object": { "basename": "ja6b13031_si_001.pdf", "url": "https://authors.library.caltech.edu/records/e40wa-gyv79/files/ja6b13031_si_001.pdf" }, "related_objects": [ { "basename": "jacs_2E6b13031.pdf", "url": "https://authors.library.caltech.edu/records/e40wa-gyv79/files/jacs_2E6b13031.pdf" } ], "pub_year": "2017", "author_list": "Liu, Wen-Bo; Schuman, David P.; et al." }, { "id": "https://authors.library.caltech.edu/records/n5fa1-84d93", "eprint_id": 89638, "eprint_status": "archive", "datestamp": "2023-08-19 03:12:28", "lastmod": "2023-10-18 22:53:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Solar-Driven Reduction of 1 atm CO_2 to Formate at 10% Energy-Conversion Efficiency by Use of a TiO_2-Protected III-V Tandem Photoanode in Conjunction with a Bipolar Membrane and a Pd/C Cathode Electrocatalyst", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 ECS - The Electrochemical Society. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. The authors also thank N. Dalleska (Caltech) for his assistance with measurements and analysis of the ICPMS and TIC data.", "abstract": "A solar-driven CO_2-reduction (CO2R) cell, consisting of a tandem GaAs/InGaP/TiO_2/Ni photoanode in 1.0 M KOH(aq) (pH=13.7) to facilitate the oxygen-evolution reaction (OER), a Pd/C nanoparticle-coated Ti mesh cathode in 2.8 M KHCO_3(aq) (pH=8.0) to perform the CO_2R reaction, and a bipolar membrane to allow for steady-state operation of the catholyte and anolyte at different bulk pH values, was constructed. At the operational current density of 8.5 mA cm^(-2), in 2.8 M KHCO_3(aq), the cathode exhibited <100 mV overpotential and >94% Faradaic efficiency for the reduction of 1 atm of CO_2(g)to formate. The anode exhibited 320 \u00b1 7 mV overpotential for the OER in 1.0 M KOH(aq), and the bipolar membrane exhibited ~480 mV voltage loss with minimal product crossover as well as >90% and >95% selectivity for protons and hydroxide ions, respectively. The solar-driven CO_2R cell converted sunlight to fuels at an energy-conversion efficiency of ~10%.", "date": "2017-05-20", "date_type": "published", "publication": "ECS Transactions", "volume": "77", "number": "4", "publisher": "Electrochemical Society", "pagerange": "31-41", "id_number": "CaltechAUTHORS:20180914-100811320", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180914-100811320", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1149/07704.0031ecst", "pub_year": "2017", "author_list": "Zhou, Xinghao; Liu, Rui; et al." }, { "id": "https://authors.library.caltech.edu/records/qx77q-jx137", "eprint_id": 76991, "eprint_status": "archive", "datestamp": "2023-08-19 03:06:30", "lastmod": "2025-04-23 19:06:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sherrott-Michelle-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Hon-Philip-W-C", "name": { "family": "Hon", "given": "Philip W. C." }, "orcid": "0000-0001-7507-4571" }, { "id": "Fountaine-Katherine-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Garcia-Juan-C", "name": { "family": "Garcia", "given": "Juan C." } }, { "id": "Ponti-Samuel-M", "name": { "family": "Ponti", "given": "Samuel M." } }, { "id": "Brar-Victor-Watson", "name": { "family": "Brar", "given": "Victor Watson" } }, { "id": "Sweatlock-Luke-A", "name": { "family": "Sweatlock", "given": "Luke A." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Experimental Demonstration of >230\u00b0 Phase Modulation in Gate-Tunable Graphene-Gold Reconfigurable Mid-Infrared Metasurfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "Metasurface, graphene, phase modulation, field-effect modulation, beam steering, mid-infrared", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: January 26, 2017; Revised: April 15, 2017; Published: April 26, 2017. \n\nThis work was supported by the U.S. Department of Energy (DOE) Office of Science, under Grant No. DE-FG02-07ER46405. M.C.S. acknowledges support by the Resnick Sustainability Institute. This research used facilities of the DOE 'Light-Material Interactions in Energy Conversion' Energy Frontier Research Center. \n\nAuthor Contributions: M.C.S. and P.W.C.H. are equal contributors. \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1701.08221.pdf

Supplemental Material - nl7b00359_si_001.pdf

", "abstract": "Metasurfaces offer significant potential to control far-field light propagation through the engineering of amplitude, polarization, and phase at an interface. We report here phase modulation of an electronically reconfigurable metasurface and demonstrate its utility for mid-infrared beam steering. Using a gate-tunable graphene-gold resonator geometry, we demonstrate highly tunable reflected phase at multiple wavelengths and show up to 237\u00b0 phase modulation range at an operating wavelength of 8.50 \u03bcm. We observe a smooth monotonic modulation of phase with applied voltage from 0\u00b0 to 206\u00b0 at a wavelength of 8.70 \u03bcm. Based on these experimental data, we demonstrate with antenna array calculations an average beam steering efficiency of 23% for reflected light for angles up to 30\u00b0 for this range of phases, confirming the suitability of this geometry for reconfigurable mid-infrared beam steering devices. By incorporating all non-idealities of the device into the antenna array calculations including absorption losses which could be mitigated, 1% absolute efficiency is achievable up to 30\u00b0.", "date": "2017-05-10", "date_type": "published", "publication": "Nano Letters", "volume": "17", "number": "5", "publisher": "American Chemical Society", "pagerange": "3027-3034", "id_number": "CaltechAUTHORS:20170427-095318741", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170427-095318741", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.7b00359", "primary_object": { "basename": "1701.08221.pdf", "url": "https://authors.library.caltech.edu/records/qx77q-jx137/files/1701.08221.pdf" }, "related_objects": [ { "basename": "nl7b00359_si_001.pdf", "url": "https://authors.library.caltech.edu/records/qx77q-jx137/files/nl7b00359_si_001.pdf" } ], "pub_year": "2017", "author_list": "Sherrott, Michelle C.; Hon, Philip W. C.; et al." }, { "id": "https://authors.library.caltech.edu/records/eyt49-dzw75", "eprint_id": 74829, "eprint_status": "archive", "datestamp": "2023-08-22 19:53:37", "lastmod": "2025-04-24 19:35:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Herwig-Lukas", "name": { "family": "Herwig", "given": "Lukas" } }, { "id": "Rice-Austin-J", "name": { "family": "Rice", "given": "Austin J." } }, { "id": "Bedbrook-Claire-N", "name": { "family": "Bedbrook", "given": "Claire N." }, "orcid": "0000-0003-3973-598X" }, { "id": "Zhang-Ruijie-K", "name": { "family": "Zhang", "given": "Ruijie K." }, "orcid": "0000-0002-7251-5527" }, { "id": "Lignell-Antti", "name": { "family": "Lignell", "given": "Antti" }, "orcid": "0000-0001-7664-5583" }, { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." } }, { "id": "Renata-Hans", "name": { "family": "Renata", "given": "Hans" }, "orcid": "0000-0003-2468-2328" }, { "id": "Dodani-Sheel-C", "name": { "family": "Dodani", "given": "Sheel C." } }, { "id": "Cho-Inha", "name": { "family": "Cho", "given": "Inha" }, "orcid": "0000-0002-7564-5378" }, { "id": "Cai-Long", "name": { "family": "Cai", "given": "Long" }, "orcid": "0000-0002-7154-5361" }, { "id": "Gradinaru-V", "name": { "family": "Gradinaru", "given": "Viviana" }, "orcid": "0000-0001-5868-348X" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Directed Evolution of a Bright Near-Infrared Fluorescent Rhodopsin Using a Synthetic Chromophore", "ispublished": "pub", "full_text_status": "public", "keywords": "synthetic chromophore substitution; directed evolution; protein engineering; near-infrared fluorescence; Archaerhodopsin; live-cell imaging", "note": "\u00a9 2017 Elsevier Ltd. \n\nReceived 1 July 2016, Revised 28 November 2016, Accepted 1 February 2017, Available online 2 March 2017. Published: March 2, 2017. \n\nThe authors would like to thank Sabine Brinkmann-Chen and Andrew Buller for critical review of the manuscript and David VanderVelde for assistance with NMR analysis. L.H. was supported by a fellowship from the Swiss National Science Foundation (SNSF; P2BSP3_151863). The Ruth L. Kirschstein National Research Service Award supports A.J.R. (F32GM116319), C.N.B. (F31MH102913), and S.C.D. (5F32GM106618). R.K.Z. was supported by a National Science Foundation Graduate Research Fellowship (NSF GRFP; DGE-1144469), is a trainee in the Caltech Biotechnology Leadership Program, and has received financial support from the Donna and Benjamin M. Rosen Bioengineering Center. J.K.B.C. acknowledges the support of the Resnick Sustainability Institute (Caltech). Research is supported by the National Center for Research Resources, ARRA SIG Program S10RR027203 (F.H.A.); National Institute of Mental Health R21MH103824 (V.G. and F.H.A.); and the Institute for Collaborative Biotechnologies through grant number W911F-09-0001 from the US Army Research Office (F.H.A.). The authors would like to acknowledge the Beckman Institute for the Resource Center on CLARITY, Optogenetics, and Vector Engineering for technology development and broad dissemination (http://www.beckmaninstitute.caltech.edu/clover.shtml). The content is solely the responsibility of the authors and does not necessarily reflect the position or policy of the National Center for Research Resources, the NIH, or the Government, and no official endorsement should be inferred.\n\n

Accepted Version - nihms850709.pdf

Supplemental Material - mmc1.pdf

Supplemental Material - mmc2.zip

", "abstract": "By engineering a microbial rhodopsin, Archaerhodopsin-3 (Arch), to bind a synthetic chromophore, merocyanine retinal, in place of the natural chromophore all-trans-retinal (ATR), we generated a protein with exceptionally bright and unprecedentedly red-shifted near-infrared (NIR) fluorescence. We show that chromophore substitution generates a fluorescent Arch complex with a 200-nm bathochromic excitation shift relative to ATR-bound wild-type Arch and an emission maximum at 772 nm. Directed evolution of this complex produced variants with pH-sensitive NIR fluorescence and molecular brightness 8.5-fold greater than the brightest ATR-bound Arch variant. The resulting proteins are well suited to bacterial imaging; expression and stability have not been optimized for mammalian cell imaging. By targeting both the protein and its chromophore, we overcome inherent challenges associated with engineering bright NIR fluorescence into Archaerhodopsin. This work demonstrates an efficient strategy for engineering non-natural, tailored properties into microbial opsins, properties relevant for imaging and interrogating biological systems.", "date": "2017-03-16", "date_type": "published", "publication": "Cell Chemical Biology", "volume": "24", "number": "3", "publisher": "Cell Press", "pagerange": "415-425", "id_number": "CaltechAUTHORS:20170307-082231020", "issn": "2451-9456", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170307-082231020", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2BSP3_151863" }, { "agency": "NIH Predoctoral Fellowship", "grant_number": "F32GM116319" }, { "agency": "NIH Predoctoral Fellowship", "grant_number": "F31MH102913" }, { "agency": "NIH", "grant_number": "5F32GM106618" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Donna and Benjamin M. Rosen Bioengineering Center" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "S10RR027203" }, { "agency": "NIH", "grant_number": "R21MH103824" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911F-09-0001" }, { "agency": "National Institute of Mental Health (NIMH)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Caltech-Center-for-Environmental-Microbial-Interactions-(CEMI)" }, { "id": "Rosen-Bioengineering-Center" } ] }, "doi": "10.1016/j.chembiol.2017.02.008", "pmcid": "PMC5357175", "primary_object": { "basename": "mmc1.pdf", "url": "https://authors.library.caltech.edu/records/eyt49-dzw75/files/mmc1.pdf" }, "related_objects": [ { "basename": "mmc2.zip", "url": "https://authors.library.caltech.edu/records/eyt49-dzw75/files/mmc2.zip" }, { "basename": "nihms850709.pdf", "url": "https://authors.library.caltech.edu/records/eyt49-dzw75/files/nihms850709.pdf" } ], "pub_year": "2017", "author_list": "Herwig, Lukas; Rice, Austin J.; et al." }, { "id": "https://authors.library.caltech.edu/records/7m0wa-trn51", "eprint_id": 75055, "eprint_status": "archive", "datestamp": "2023-08-19 02:03:01", "lastmod": "2023-10-25 14:42:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Tzu-Pin", "name": { "family": "Lin", "given": "Tzu-Pin" }, "orcid": "0000-0001-7041-7213" }, { "id": "Chang-Alice-B", "name": { "family": "Chang", "given": "Alice B." }, "orcid": "0000-0001-5036-2681" }, { "id": "Chen-Hsiang-Yun", "name": { "family": "Chen", "given": "Hsiang-Yun" }, "orcid": "0000-0002-6461-1519" }, { "id": "Liberman-Martin-A-L", "name": { "family": "Liberman-Martin", "given": "Allegra L." }, "orcid": "0000-0002-8447-905X" }, { "id": "Bates-C-M", "name": { "family": "Bates", "given": "Christopher M." }, "orcid": "0000-0002-1598-794X" }, { "id": "Voegtle-M-J", "name": { "family": "Voegtle", "given": "Matthew J." } }, { "id": "Bauer-C-A", "name": { "family": "Bauer", "given": "Christina A." }, "orcid": "0000-0002-7687-1676" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Control of Grafting Density and Distribution in Graft Polymers by Living Ring-Opening Metathesis Copolymerization", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: January 23, 2017; Published: February 21, 2017. \n\nThis work was supported by the U.S. Department of Energy under award number DE-AR0000683 (ARPA-E program) and by the National Science Foundation under award number CHE-1502616. A.B.C. thanks the U.S. Department of Defense for support through the NDSEG fellowship. A.L.L.-M. thanks the Resnick Sustainability Institute at Caltech for fellowship support. C.M.B. thanks UCSB for funding and the Materials Research Laboratory, a Materials Research Science and Engineering Center (MRSEC) under support from the National Science Foundation (DMR-1121053). C.A.B. thanks the W.M. Keck Foundation for instrumental support. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja7b00791_si_001.pdf

", "abstract": "Control over polymer sequence and architecture is crucial to both understanding structure\u2013property relationships and designing functional materials. In pursuit of these goals, we developed a new synthetic approach that enables facile manipulation of the density and distribution of grafts in polymers via living ring-opening metathesis polymerization (ROMP). Discrete endo,exo-norbornenyl dialkylesters (dimethyl DME, diethyl DEE, di-n-butyl DBE) were strategically designed to copolymerize with a norbornene-functionalized polystyrene (PS), polylactide (PLA), or polydimethylsiloxane (PDMS) macromonomer mediated by the third-generation metathesis catalyst (G3). The small-molecule diesters act as diluents that increase the average distance between grafted side chains, generating polymers with variable grafting density. The grafting density (number of side chains/number of norbornene backbone repeats) could be straightforwardly controlled by the macromonomer/diluent feed ratio. To gain insight into the copolymer sequence and architecture, self-propagation and cross-propagation rate constants were determined according to a terminal copolymerization model. These kinetic analyses suggest that copolymerizing a macromonomer/diluent pair with evenly matched self-propagation rate constants favors randomly distributed side chains. As the disparity between macromonomer and diluent homopolymerization rates increases, the reactivity ratios depart from unity, leading to an increase in gradient tendency. To demonstrate the effectiveness of our method, an array of monodisperse polymers (PLA^x-ran-DME^(1-x))_n bearing variable grafting densities (x = 1.0, 0.75, 0.5, 0.25) and total backbone degrees of polymerization (n = 167, 133, 100, 67, 33) were synthesized. The approach disclosed in this work therefore constitutes a powerful strategy for the synthesis of polymers spanning the linear-to-bottlebrush regimes with controlled grafting density and side chain distribution, molecular attributes that dictate micro- and macroscopic properties.", "date": "2017-03-15", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "10", "publisher": "American Chemical Society", "pagerange": "3896-3903", "id_number": "CaltechAUTHORS:20170313-100455922", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170313-100455922", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AR0000683" }, { "agency": "NSF", "grant_number": "CHE-1502616" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1121053" }, { "agency": "W. M. Keck Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.7b00791", "primary_object": { "basename": "ja7b00791_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7m0wa-trn51/files/ja7b00791_si_001.pdf" }, "pub_year": "2017", "author_list": "Lin, Tzu-Pin; Chang, Alice B.; et al." }, { "id": "https://authors.library.caltech.edu/records/djazs-3ee53", "eprint_id": 74458, "eprint_status": "archive", "datestamp": "2023-08-19 02:00:41", "lastmod": "2025-04-25 22:22:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ye-Ruquan", "name": { "family": "Ye", "given": "Ruquan" }, "orcid": "0000-0002-2543-9090" }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Zhang-Haoke", "name": { "family": "Zhang", "given": "Haoke" } }, { "id": "Su-Huifang", "name": { "family": "Su", "given": "Huifang" } }, { "id": "Zhang-Yilin", "name": { "family": "Zhang", "given": "Yilin" } }, { "id": "Xu-Liguo", "name": { "family": "Xu", "given": "Liguo" } }, { "id": "Hu-Rongrong", "name": { "family": "Hu", "given": "Rongrong" } }, { "id": "Kwok-Ryan-T-K", "name": { "family": "Kwok", "given": "Ryan T. K." } }, { "id": "Wong-Kam-Sing", "name": { "family": "Wong", "given": "Kam Sing" } }, { "id": "Lam-Jack-W-Y", "name": { "family": "Lam", "given": "Jacky W. Y." } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Tang-Ben-Zhong", "name": { "family": "Tang", "given": "Ben Zhong" } } ] }, "title": "Non-conventional fluorescent biogenic and synthetic polymers without aromatic rings", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 The Royal Society of Chemistry. \n\nReceived 24 Jan 2017, Accepted 07 Feb 2017, First published online 08 Feb 2017. \n\nThis work was partially supported by the National Basic Research Program of China (973 Program, 2013CB834701 and 2013CB834702), the University Grants Committee of Hong Kong (AoE/P-03/08), the Innovation and Technology Commission (ITCCNERC14S01), the Research Grants Council of Hong Kong (16301614, 16305015 and N_HKUST604/14), and the Guangdong Innovative Research Team Program (201101C0105067115). YL acknowledges the support from the Resnick Prize Postdoctoral Fellowship at Caltech. This work used computational resources of NREL Peregrine, DOE NERSC, and NSF XSEDE. \n\nAuthor contributions: R. Y. and B. T. designed the experiments. R. Y. synthesized all the oligopeptides, polypeptides, and biomimetic polymers, and obtained the NMR, FTIR, PL emission spectra. Y. L. and W. A. G. carried out the theoretical modelling and calculation. R. Y. and H. Z. obtained the CD spectra. H. S. obtained the confocal images. L. X. and R. H. performed the fluorescence lifetime measurement. Y. Z. and K. S. W. performed the quantum yield measurement. R. T. K. K. and J. W. Y. L. revised the manuscript. R. Y. and B. T. wrote the manuscript with comments from all authors.\n\n

Supplemental Material - c7py00154a1.pdf

Supplemental Material - c7py00154a2.mp4

Supplemental Material - c7py00154a3.mp4

", "abstract": "Non-conventional fluorescent materials without aromatic structures have attracted much research attention in recent years. However, the working mechanism responsible for their fluorescence remains mysterious. Here we decipher the origin of fluorescence by studying the photophysical properties of a series of non-aromatic biogenic and synthetic peptides. An experimental study suggests that the turn-on fluorescence in the aggregation state/condensed phase is associated with the communication of amide groups, where hydrogen bonds are playing a critical role in bringing these functionalities into close proximity. This explanation is further justified by the study of the hierarchical influence on fluorescence and applied to biomimetic polymers in a more general content. This discovery provides a more comprehensive insight into the bioluminescence system. It may stimulate future development of new fluorescent materials, and inspire research on disease diagnostics, biomechanics measurements, etc. that are associated with protein morphology.", "date": "2017-03-14", "date_type": "published", "publication": "Polymer Chemistry", "volume": "8", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "1722-1727", "id_number": "CaltechAUTHORS:20170222-090600137", "issn": "1759-9954", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170222-090600137", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Basic Research Program of China", "grant_number": "2013CB834701" }, { "agency": "National Basic Research Program of China", "grant_number": "2013CB834702" }, { "agency": "University Grants Committee of Hong Kong", "grant_number": "AoE/P-03/08" }, { "agency": "Innovation and Technology Commission", "grant_number": "ITCCNERC14S01" }, { "agency": "Research Grants Council of Hong Kong", "grant_number": "16301614" }, { "agency": "Research Grants Council of Hong Kong", "grant_number": "16305015" }, { "agency": "Research Grants Council of Hong Kong", "grant_number": "N_HKUST604/14" }, { "agency": "Guangdong Innovative Research Team Program", "grant_number": "201101C0105067115" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c7py00154a", "primary_object": { "basename": "c7py00154a1.pdf", "url": "https://authors.library.caltech.edu/records/djazs-3ee53/files/c7py00154a1.pdf" }, "related_objects": [ { "basename": "c7py00154a2.mp4", "url": "https://authors.library.caltech.edu/records/djazs-3ee53/files/c7py00154a2.mp4" }, { "basename": "c7py00154a3.mp4", "url": "https://authors.library.caltech.edu/records/djazs-3ee53/files/c7py00154a3.mp4" } ], "pub_year": "2017", "author_list": "Ye, Ruquan; Liu, Yuanyue; et al." }, { "id": "https://authors.library.caltech.edu/records/4tacc-3wg67", "eprint_id": 74434, "eprint_status": "archive", "datestamp": "2023-08-19 01:40:06", "lastmod": "2025-04-23 00:50:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-Ana-M", "name": { "family": "Brown", "given": "Ana M." } }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Schwartzberg-Adam-M", "name": { "family": "Schwartzberg", "given": "Adam M." }, "orcid": "0000-0001-6335-0719" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Experimental and Ab Initio Ultrafast Carrier Dynamics in Plasmonic Nanoparticles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Physical Society. \n\n(Received 11 August 2016; published 21 February 2017) \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors acknowledge support from NG NEXT at Northrop Grumman Corporation. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. P.\u2009N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.\u2009M.\u2009B. is supported by a National Science Foundation Graduate Research Fellowship, a Link Foundation Energy Fellowship, and the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (DE-SC0001293).\n\n

Published - PhysRevLett.118.087401.pdf

Submitted - 1608.03309.pdf

Supplemental Material - SI.pdf

", "abstract": "Ultrafast pump-probe measurements of plasmonic nanostructures probe the nonequilibrium behavior of excited carriers, which involves several competing effects obscured in typical empirical analyses. Here we present pump-probe measurements of plasmonic nanoparticles along with a complete theoretical description based on first-principles calculations of carrier dynamics and optical response, free of any fitting parameters. We account for detailed electronic-structure effects in the density of states, excited carrier distributions, electron-phonon coupling, and dielectric functions that allow us to avoid effective electron temperature approximations. Using this calculation method, we obtain excellent quantitative agreement with spectral and temporal features in transient-absorption measurements. In both our experiments and calculations, we identify the two major contributions of the initial response with distinct signatures: short-lived highly nonthermal excited carriers and longer-lived thermalizing carriers.", "date": "2017-02-24", "date_type": "published", "publication": "Physical Review Letters", "volume": "118", "number": "8", "publisher": "American Physical Society", "pagerange": "Art. No. 087401", "id_number": "CaltechAUTHORS:20170221-134853641", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170221-134853641", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Link Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "other_numbering_system": { "items": [ { "id": "1257", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevLett.118.087401", "primary_object": { "basename": "1608.03309.pdf", "url": "https://authors.library.caltech.edu/records/4tacc-3wg67/files/1608.03309.pdf" }, "related_objects": [ { "basename": "PhysRevLett.118.087401.pdf", "url": "https://authors.library.caltech.edu/records/4tacc-3wg67/files/PhysRevLett.118.087401.pdf" }, { "basename": "SI.pdf", "url": "https://authors.library.caltech.edu/records/4tacc-3wg67/files/SI.pdf" } ], "pub_year": "2017", "author_list": "Brown, Ana M.; Sundararaman, Ravishankar; et al." }, { "id": "https://authors.library.caltech.edu/records/36aza-saz71", "eprint_id": 71018, "eprint_status": "archive", "datestamp": "2023-08-19 01:34:22", "lastmod": "2023-10-23 15:16:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." }, "orcid": "0000-0001-8849-4516" }, { "id": "Werlang-Caroline-A", "name": { "family": "Werlang", "given": "Caroline A." }, "orcid": "0000-0001-7554-8431" }, { "id": "Baumschlager-Armin", "name": { "family": "Baumschlager", "given": "Armin" }, "orcid": "0000-0002-2546-9038" }, { "id": "Brinkmann-Chen-Sabine", "name": { "family": "Brinkmann-Chen", "given": "Sabine" }, "orcid": "0000-0002-5419-4192" }, { "id": "Mayo-S-L", "name": { "family": "Mayo", "given": "Stephen L." }, "orcid": "0000-0002-9785-5018" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "A General Tool for Engineering the NAD/NADP Cofactor Preference of Oxidoreductases", "ispublished": "pub", "full_text_status": "public", "keywords": "cofactor specificity, oxidoreductases, protein engineering, library design, semirational engineering", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: July 7, 2016; Published: September 20, 2016. \n\nThis work was supported by the Gordon and Betty Moore Foundation through Grant No. GBMF2809 to the Caltech Programmable Molecular Technology Initiative and by American Recovery and Reinvestment Act (ARRA) funds through the National Institutes of Health Shared Instrumentation Grant Program, Grant No. S10RR027203, to F.H.A. J.K.B.C. acknowledges the support of the Resnick Sustainability Institute (Caltech). The authors thank Ruchi Jahagirdar and Lisa Mears for experimental assistance and Tilman Flock for providing the list of nonredundant PDBs used for CSR-SALAD testing and validation. They also thank numerous former and current members of the Arnold and Mayo laboratories for invaluable suggestions and discussions. \n\nAccession Codes: PDB: 4XDY, PDB: 4TSK, PDB: 3DOJ, PDB: 1PIW, PDB: 1K8C, PDB: 1VHD, PDB: 3PEF \n\nAuthor Contributions: This project was conceived by J.K.B.C., S.B-C., S.L.M., and F.H.A. J.K.B.C. designed and programmed CSR-SALAD, which was implemented online by C.A.W. J.K.B.C. performed the validation experiments with assistance from A.B., and produced the figures and tables. J.K.B.C., S.B-C., and F.H.A. wrote the manuscript with input from all authors. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms-1754172.pdf

Supplemental Material - sb6b00188_si_001.pdf

", "abstract": "The ability to control enzymatic nicotinamide cofactor utilization is critical for engineering efficient metabolic pathways. However, the complex interactions that determine cofactor-binding preference render this engineering particularly challenging. Physics-based models have been insufficiently accurate and blind directed evolution methods too inefficient to be widely adopted. Building on a comprehensive survey of previous studies and our own prior engineering successes, we present a structure-guided, semirational strategy for reversing enzymatic nicotinamide cofactor specificity. This heuristic-based approach leverages the diversity and sensitivity of catalytically productive cofactor binding geometries to limit the problem to an experimentally tractable scale. We demonstrate the efficacy of this strategy by inverting the cofactor specificity of four structurally diverse NADP-dependent enzymes: glyoxylate reductase, cinnamyl alcohol dehydrogenase, xylose reductase, and iron-containing alcohol dehydrogenase. The analytical components of this approach have been fully automated and are available in the form of an easy-to-use web tool: Cofactor Specificity Reversal\u2013Structural Analysis and Library Design (CSR-SALAD).", "date": "2017-02-17", "date_type": "published", "publication": "ACS Synthetic Biology", "volume": "6", "number": "2", "publisher": "American Chemical Society", "pagerange": "326-333", "id_number": "CaltechAUTHORS:20161012-112258970", "issn": "2161-5063", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161012-112258970", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2809" }, { "agency": "NIH", "grant_number": "S10RR027203" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acssynbio.6b00188", "pmcid": "PMC8611728", "primary_object": { "basename": "nihms-1754172.pdf", "url": "https://authors.library.caltech.edu/records/36aza-saz71/files/nihms-1754172.pdf" }, "related_objects": [ { "basename": "sb6b00188_si_001.pdf", "url": "https://authors.library.caltech.edu/records/36aza-saz71/files/sb6b00188_si_001.pdf" } ], "pub_year": "2017", "author_list": "Cahn, Jackson K. B.; Werlang, Caroline A.; et al." }, { "id": "https://authors.library.caltech.edu/records/js0cj-n0r58", "eprint_id": 72573, "eprint_status": "archive", "datestamp": "2023-08-19 01:34:35", "lastmod": "2023-10-23 22:44:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Salata-M", "name": { "family": "Salata", "given": "Mike" } }, { "id": "Fedorov-Alexey", "name": { "family": "Fedorov", "given": "Alexey" }, "orcid": "0000-0001-9814-6726" }, { "id": "Yang-Yun-Fang", "name": { "family": "Yang", "given": "Yun-Fang" }, "orcid": "0000-0002-6287-1640" }, { "id": "Liang-Yong", "name": { "family": "Liang", "given": "Yong" }, "orcid": "0000-0002-7225-7062" }, { "id": "Cariou-R", "name": { "family": "Cariou", "given": "Romain" } }, { "id": "Betz-K-N", "name": { "family": "Betz", "given": "Kerry N." }, "orcid": "0000-0001-9118-5909" }, { "id": "Couzijn-E-P-A", "name": { "family": "Couzijn", "given": "Erik P. A." } }, { "id": "Shabaker-J-W", "name": { "family": "Shabaker", "given": "John W." } }, { "id": "Houk-K-N", "name": { "family": "Houk", "given": "Kendall N." }, "orcid": "0000-0002-8387-5261" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "A potassium tert-butoxide and hydrosilane system for ultra-deep desulfurization of fuels", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Macmillan Publishers Limited. \n\nReceived 30 July 2016; accepted 13 January 2017; published 17 February 2017. \n\nSupport of this work by BP under the XC2 program is gratefully acknowledged. A.A.T. is additionally grateful to the Resnick Sustainability Institute at Caltech, Dow Chemical, and Bristol\u2013Myers Squibb for predoctoral fellowships, and to NSERC for a PGS D fellowship. K.N.H. is grateful to the US National Science Foundation (CHE-1205646 and CHE-1361104) for financial support and to the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by the US National Science Foundation (OCI-1053575). Y.L. thanks the 'National Thousand Young Talents Program' and 'Jiangsu Specially-Appointed Professor Plan' in China for financial support. E.P.A.C. thanks K. Lammertsma (Division of Organic Chemistry, Vrije Universiteit Amsterdam, The Netherlands) for access to, and SURFsara (www.surfsara.nl) for their support in using the Lisa Computer Cluster. G. Huff, G. Sunley, D. Braden, P. Metelski, M. Pinderski, E. Doskocil, A. Lucy, C. Buda, A. Dinse, R. Taylor, J. Bercaw, J. Labinger, M. Howard, M. Desmond, J. Elks, D. Leitch and F. Bell are gratefully thanked for technical contributions and/or invaluable discussion. \n\nAuthor Contributions: A.A.T., A.F. and R.H.G. had the idea and designed experiments with M.S., J.W.S., R.C. and K.N.B. A.A.T., M.S., A.F. and K.N.B. performed experiments and analysed data. Y.-F.Y., Y.L., E.P.A.C. and K.N.H. designed, performed, analysed, and interpreted density functional theory calculations. A.A.T., A.F., M.S., K.N.B. and E.P.A.C. wrote the manuscript with contributions from all authors. All authors contributed to discussions. \n\nData availability: Computational data are available in Supplementary Table 1 and Supplementary Data 1. Further data that support the plots within this paper and other findings of this study should be requested directly from the corresponding authors. \n\nCompeting interests: A company commercializing the technology reported in this paper is being founded and one of the authors (A.A.T.) will be a co-founder. The other authors declare no competing interests.\n\n

Supplemental Material - nenergy20178-s1.pdf

Supplemental Material - nenergy20178-s2.xlsx

", "abstract": "Hydrodesulfurization (HDS) is the process by which sulfur-containing impurities are removed from petroleum streams, typically using a heterogeneous, sulfided transition metal catalyst under high H_2 pressures and temperatures. Although generally effective, a major obstacle that remains is the desulfurization of highly refractory sulfur-containing heterocycles, such as 4,6-dimethyldibenzothiophene (4,6-Me_2DBT), which are naturally occurring in fossil fuels. Homogeneous HDS strategies using well-defined molecular catalysts have been designed to target these recalcitrant S-heterocycles; however, the formation of stable transition metal sulfide complexes following C\u2013S bond activation has largely prevented catalytic turnover. Here we show that a robust potassium (K) alkoxide (O)/hydrosilane (Si)-based ('KOSi') system efficiently desulfurizes refractory sulfur heterocycles. Subjecting sulfur-rich diesel (that is, [S] \u223c 10,000\u2009ppm) to KOSi conditions results in a fuel with [S] \u223c 2\u2009ppm, surpassing ambitious future governmental regulatory goals set for fuel sulfur content in all countries. \n\nFossil fuels contain naturally occurring organosulfur impurities, with quantities varying depending on the type of feedstock. These sulfur-containing organic small molecules poison catalytic converters and generate polluting sulfur dioxides when combusted. Hydrodesulfurization (HDS) is the industrial process by which sulfur impurities are removed from petroleum fractions prior to their use as fuels. Currently, HDS is performed by treating petroleum with H_2 at high pressures and temperatures (that is, 150\u20132,250 psi and 400\u2009\u00b0C) over heterogeneous catalysts such as cobalt-doped molybdenum sulfide supported on alumina (that is, CoMoS_x\u2215\u03b3-Al_2O_3; Fig. 1a). However, certain organosulfur species, in particular dibenzothiophenes alkylated at positions 4 and 6, are not efficiently removed. Homogeneous strategies employing sophisticated, well-defined transition metal complexes\u2014including those based on platinum, nickel, tungsten, molybdenum, palladium, ruthenium, rhodium, iron, cobalt, and others\u2014have been extensively investigated. While these studies have provided valuable mechanistic insights, several fundamental issues, such as the formation of stable organometallic S\u2013M species upon C\u2013S bond activation by the metal centre (Fig. 1b), generally restrict industrial implementation of such methods. Rare examples of desulfurization of dibenzothiophenes alkylated at the 4 and 6 positions by homogeneous transition metal catalysis utilized either Ni compounds in combination with superstoichiometric alkyl Grignard reagents or Ni or Co phosphoranimide complexes in the presence of superstoichiometric KH. These issues pose a formidable challenge for the development of new HDS methods. Moreover, increasingly strict governmental regulations require limiting the sulfur content in diesel fuel and gasoline (in the US: typically <15 and <30\u2009ppm, respectively) as well as other fuels, rendering the development of new powerful HDS methods a primary global concern. \n\nIn 2013, Grubbs and co-workers reported the KO^tBu mediated cleavage of aryl C\u2013O bonds in lignin models in the absence of transition metals using hydrosilanes. Careful inductively coupled plasma mass spectrometry (ICP-MS) analyses of the reagents and reaction mixtures ruled out catalysis with transition metals. We thus became interested in extending this method to sulfur heterocycles of relevance in oil and gas refining applications. Herein, we report that the robust KOtBu/silane-based (that is, KOSi) system is a powerful and effective homogeneous HDS method, which desulfurizes HDS-resistant dibenzothiophenes in good yield and reduces the sulfur content in diesel fuel to remarkably low levels (Fig. 1c).", "date": "2017-02-17", "date_type": "published", "publication": "Nature Energy", "volume": "2", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 17008", "id_number": "CaltechAUTHORS:20161205-153231512", "issn": "2058-7546", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161205-153231512", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "BP XC2 Program" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "Bristol-Myers Squibb" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1361104" }, { "agency": "NSF", "grant_number": "OCI-1053575" }, { "agency": "National Thousand Young Talents program of China" }, { "agency": "Jiangsu Specially-Appointed Professor Plan" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nenergy.2017.8", "primary_object": { "basename": "nenergy20178-s1.pdf", "url": "https://authors.library.caltech.edu/records/js0cj-n0r58/files/nenergy20178-s1.pdf" }, "related_objects": [ { "basename": "nenergy20178-s2.xlsx", "url": "https://authors.library.caltech.edu/records/js0cj-n0r58/files/nenergy20178-s2.xlsx" } ], "pub_year": "2017", "author_list": "Toutov, Anton A.; Salata, Mike; et al." }, { "id": "https://authors.library.caltech.edu/records/7ddwn-q5685", "eprint_id": 73722, "eprint_status": "archive", "datestamp": "2023-08-19 01:23:14", "lastmod": "2023-10-24 16:23:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Savoie-B-M", "name": { "family": "Savoie", "given": "Brett M." }, "orcid": "0000-0002-7039-4039" }, { "id": "Webb-M-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Enhancing Cation Diffusion and Suppressing Anion Diffusion via Lewis-Acidic Polymer Electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: November 14, 2016; Accepted: January 11, 2017; Published: January 11, 2017. \n\nThis research was supported by the National Science Foundation under DMREF Award Number NSF-CHE-1335486. M.A.W. also acknowledges support from the Resnick Sustainability Institute. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. This research also used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - jz6b02662_si_001.pdf

", "abstract": "Solid polymer electrolytes (SPEs) have the potential to increase both the energy density and stability of lithium-based batteries, but low Li^+ conductivity remains a barrier to technological viability. SPEs are designed to maximize Li^+ diffusivity relative to the anion while maintaining sufficient salt solubility. It is thus remarkable that poly(ethylene oxide) (PEO), the most widely used SPE, exhibits Li^+ diffusivity that is an order of magnitude smaller than that of typical counterions at moderate salt concentrations. We show that Lewis-basic polymers like PEO favor slow cation and rapid anion diffusion, while this relationship can be reversed in Lewis-acidic polymers. Using molecular dynamics, polyboranes are identified that achieve up to 10-fold increases in Li^+ diffusivities and significant decreases in anion diffusivities, relative to PEO in the dilute-ion regime. These results illustrate a general principle for increasing Li^+ diffusivity and transference number with chemistries that exhibit weaker cation and stronger anion coordination.", "date": "2017-02-02", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "8", "number": "3", "publisher": "American Chemical Society", "pagerange": "641-646", "id_number": "CaltechAUTHORS:20170125-130016983", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170125-130016983", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1335486" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpclett.6b02662", "primary_object": { "basename": "jz6b02662_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7ddwn-q5685/files/jz6b02662_si_001.pdf" }, "pub_year": "2017", "author_list": "Savoie, Brett M.; Webb, Michael A.; et al." }, { "id": "https://authors.library.caltech.edu/records/n1x82-2e617", "eprint_id": 73231, "eprint_status": "archive", "datestamp": "2023-08-19 01:20:39", "lastmod": "2023-10-24 15:08:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Betz-K-N", "name": { "family": "Betz", "given": "Kerry N." }, "orcid": "0000-0001-9118-5909" }, { "id": "Schuman-D-P", "name": { "family": "Schuman", "given": "David P." } }, { "id": "Liu-Wen-Bo", "name": { "family": "Liu", "given": "Wen-Bo" }, "orcid": "0000-0003-2687-557X" }, { "id": "Fedorov-Alexey", "name": { "family": "Fedorov", "given": "Alexey" }, "orcid": "0000-0001-9814-6726" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Alkali metal hydroxide\u2013catalyzed C(sp)\u2013H bond silylation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: November 23, 2016; Published: December 27, 2016. \n\nThis work was supported by the NSF under the CCI Center for Selective C\u2013H Functionalization (CHE-1205646) and under CHE-\n1212767. A.A.T. is grateful to Bristol\u2013Myers Squibb, the Resnick Sustainability Institute at Caltech, and to Dow Chemical for predoctoral fellowships as well as to NSERC for a PGS D fellowship. D.P.S thanks the CCI Center for Selective C\u2013H Functionalization for support. W.-B.L thanks The Shanghai Institute of Organic Chemistry (SIOC) and S.-L. You for a postdoctoral fellowship. We thank S. Virgil and the Caltech Center for Catalysis and Chemical Synthesis for access to analytical equipment. M. Shahgoli and N. Torian (Caltech) are acknowledged for assistance with high-resolution mass spectrometry. \n\nA.A.T. and K.N.B. contributed equally. \n\nThe authors declare no competing financial interests.\n\n

Accepted Version - jacs_2E6b12114.pdf

Supplemental Material - ja6b12114_si_001.pdf

", "abstract": "Disclosed is a mild, scalable, and chemoselective catalytic cross-dehydrogenative C\u2013H bond functionalization protocol for the construction of C(sp)\u2013Si bonds in a single step. The scope of the alkyne and hydrosilane partners is substantial, providing an entry point into various organosilane building blocks and additionally enabling the discovery of a number of novel synthetic strategies. Remarkably, the optimal catalysts are NaOH and KOH.", "date": "2017-02-01", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "4", "publisher": "American Chemical Society", "pagerange": "1668-1674", "id_number": "CaltechAUTHORS:20170104-153320118", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170104-153320118", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "Bristol-Myers Squibb" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Shanghai Institute of Organic Chemistry (SIOC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.6b12114", "primary_object": { "basename": "ja6b12114_si_001.pdf", "url": "https://authors.library.caltech.edu/records/n1x82-2e617/files/ja6b12114_si_001.pdf" }, "related_objects": [ { "basename": "jacs_2E6b12114.pdf", "url": "https://authors.library.caltech.edu/records/n1x82-2e617/files/jacs_2E6b12114.pdf" } ], "pub_year": "2017", "author_list": "Toutov, Anton A.; Betz, Kerry N.; et al." }, { "id": "https://authors.library.caltech.edu/records/pwm82-tzq94", "eprint_id": 72935, "eprint_status": "archive", "datestamp": "2023-08-19 01:10:20", "lastmod": "2025-04-25 21:56:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Xiujun", "name": { "family": "Fan", "given": "Xiujun" }, "orcid": "0000-0003-4849-4305" }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Peng-Zhiwei", "name": { "family": "Peng", "given": "Zhiwei" } }, { "id": "Zhang-Zhenhua", "name": { "family": "Zhang", "given": "Zhenhua" } }, { "id": "Zhou-Haiqing", "name": { "family": "Zhou", "given": "Haiqing" } }, { "id": "Zhang-Xianming", "name": { "family": "Zhang", "given": "Xianming" } }, { "id": "Yakobson-B-I", "name": { "family": "Yakobson", "given": "Boris I." } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Guo-Xia", "name": { "family": "Guo", "given": "Xia" } }, { "id": "Hauge-R-H", "name": { "family": "Hauge", "given": "Robert H." } }, { "id": "Tour-J-M", "name": { "family": "Tour", "given": "James M." }, "orcid": "0000-0002-8479-9328" } ] }, "title": "Atomic H-Induced Mo_2C Hybrid as an Active and Stable Bifunctional Electrocatalyst", "ispublished": "pub", "full_text_status": "public", "keywords": "Mo2C, graphene nanoribbon, hydrogen-evolution reaction, oxygen-reduction reaction, atomic H", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: September 8, 2016; Accepted: December 18, 2016; Published: December 18, 2016. \n\nThe authors acknowledge Y. Yang, H. Fei, R. Ye, G. Ruan, Q. Zhong, C. Gao, L. Li, N. D. Kim and J. Lin at Rice University for helpful discussions, and the National Natural Science Foundation of China (21603129), the Air Force Office of Scientific Research (FA9550-09-1-0581), and the AFOSR MURI program (FA9550-12-1-0035) for partial support of this research. The authors would also like to acknowledge Dr. Junjie Zhang from Scientific Instrument Center at Shanxi University for her help with ICP-MS measurement. Y. L. acknowledges the support from Resnick Prize Postdoctoral Fellowship at Caltech. The computations were performed on National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, and Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation grant number ACI-1053575. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - acsnano_2E6b06089.pdf

Supplemental Material - nn6b06089_si_001.pdf

", "abstract": "Mo_2C nanocrystals (NCs) anchored on vertically aligned graphene nanoribbons (VA-GNR) as hybrid nanocatalysts (Mo_2C-GNR) are synthesized through the direct carbonization of metallic Mo with atomic H treatment. The growth mechanism of Mo2C NCs with atomic H treatment is discussed. The Mo_2C-GNR hybrid exhibits highly active and durable electrocatalytic performance for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR). For HER, in an acidic solution the Mo_2C-GNR has an onset potential of 39 mV and a Tafel slope of 65 mV dec^(-1), in a basic solution Mo_2C-GNR has an onset potential of 53 mV, and Tafel slope of 54 mV dec^(-1). It is stable in both acidic and basic media. Mo2C-GNR is a high activity ORR catalyst with a high peak current density of 2.01 mA cm^(-2), an onset potential of 0.94 V that is more positive vs reversible hydrogen electrode, a high electron transfer number n (\u223c3.86) and long-term stability.", "date": "2017-01-24", "date_type": "published", "publication": "ACS Nano", "volume": "11", "number": "1", "publisher": "American Chemical Society", "pagerange": "384-394", "id_number": "CaltechAUTHORS:20161219-100643546", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161219-100643546", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "21603129" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-09-1-0581" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0035" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "other_numbering_system": { "items": [ { "id": "1247", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsnano.6b06089", "primary_object": { "basename": "acsnano_2E6b06089.pdf", "url": "https://authors.library.caltech.edu/records/pwm82-tzq94/files/acsnano_2E6b06089.pdf" }, "related_objects": [ { "basename": "nn6b06089_si_001.pdf", "url": "https://authors.library.caltech.edu/records/pwm82-tzq94/files/nn6b06089_si_001.pdf" } ], "pub_year": "2017", "author_list": "Fan, Xiujun; Liu, Yuanyue; et al." }, { "id": "https://authors.library.caltech.edu/records/c2jh2-v6q37", "eprint_id": 71374, "eprint_status": "archive", "datestamp": "2023-08-22 19:31:58", "lastmod": "2023-10-23 15:41:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Webb-M-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Wang-Yimin", "name": { "family": "Wang", "given": "Yimin" } }, { "id": "Braams-B-J", "name": { "family": "Braams", "given": "Bastiaan J." } }, { "id": "Bowman-J-M", "name": { "family": "Bowman", "given": "Joel M." } }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Equilibrium Clumped-Isotope Effects in Doubly Substituted Isotopologues of Ethane", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Clumped isotope geochemistry; Ethane; Equilibrium isotope effects; Path-integral methods; Vibrational anharmonicity", "note": "\u00a9 2016 Elsevier B.V. \n\nReceived 13 July 2016; accepted 1 October 2016; available online 11 October 2016. \n\nThis research was supported by the Resnick Sustainability Institute and the Department of Energy (DE-SC0006593). The work of B. J. B. was performed while he was at Emory University and supported by the Office of Basic Energy Sciences and the National Science Foundation. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725. The authors also thank John Eiler, Alex Sessions, and Brian Peterson for helpful discussions as well as three anonymous reviewers for their helpful and constructive comments.", "abstract": "We combine path-integral Monte Carlo methods with a new intramolecular potential energy surface to quantify the equilibrium enrichment of doubly substituted ethane isotopologues due to clumped-isotope effects. Ethane represents the simplest molecule to simultaneously exhibit ^(13)C\u2013^(13)C, ^(13)C\u2013D, and D\u2013D clumped-isotope effects, and the analysis of corresponding signatures may provide useful geochemical and biogeochemical proxies of formation temperatures or reaction pathways. Utilizing path-integral statistical mechanics, we predict equilibrium fractionation factors that fully incorporate nuclear quantum effects, such as anharmonicity and rotational-vibrational coupling which are typically neglected by the widely used Urey model. The magnitude of the calculated fractionation factors for the doubly substituted ethane isotopologues indicates that isotopic clumping can be observed if rare-isotope substitutions are separated by up to three chemical bonds, but the diminishing strength of these effects suggests that enrichment at further separations will be negligible. The Urey model systematically underestimates enrichment due to ^(13)C\u2013D and D\u2013D clumped-isotope effects in ethane, leading to small relative errors in the apparent equilibrium temperature, ranging from 5 K at 273.15 K to 30 K at 873.15 K. We additionally note that the rotameric dependence of isotopologue enrichment must be carefully considered when using the Urey model, whereas the path-integral calculations automatically account for such effects due to configurational sampling. These findings are of direct relevance to future clumped-isotope studies of ethane, as well as studies of ^(13)C\u2013^(13)C, ^(13)C\u2013D, and D\u2013D clumped-isotope effects in other hydrocarbons.", "date": "2017-01-15", "date_type": "published", "publication": "Geochimica et Cosmochimica Acta", "volume": "197", "publisher": "Elsevier", "pagerange": "14-26", "id_number": "CaltechAUTHORS:20161024-085559620", "issn": "0016-7037", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161024-085559620", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006593" }, { "agency": "NSF" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.gca.2016.10.001", "pub_year": "2017", "author_list": "Webb, Michael A.; Wang, Yimin; et al." }, { "id": "https://authors.library.caltech.edu/records/cpwpy-jvv36", "eprint_id": 71979, "eprint_status": "archive", "datestamp": "2023-08-22 19:31:27", "lastmod": "2025-04-23 15:27:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Whitney-William-S", "name": { "family": "Whitney", "given": "William S." }, "orcid": "0000-0001-5269-2967" }, { "id": "Sherrott-Michelle-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Jariwala-Deep", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Lin-Wei-Hsiang", "name": { "family": "Lin", "given": "Wei-Hsiang" }, "orcid": "0000-0003-0037-1277" }, { "id": "Bechtel-Hans-A", "name": { "family": "Bechtel", "given": "Hans A." }, "orcid": "0000-0002-7606-9333" }, { "id": "Rossman-G-R", "name": { "family": "Rossman", "given": "George R." }, "orcid": "0000-0002-4571-6884" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Field Effect Optoelectronic Modulation of Quantum-Confined Carriers in Black Phosphorus", "ispublished": "pub", "full_text_status": "public", "keywords": "Black phosphorus; Burstein\u2212Moss shift; mid-infrared; optical modulator; quantum-confined Franz-Keldysh effect; tunable optical properties", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: August 10, 2016; Revised: December 11, 2016; Published: December 22, 2016. \n\nThis work was supported by the U.S. Department of Energy (DOE) Office of Science, under Grant No. DE-FG02-07ER46405. The authors gratefully acknowledge use of the facilities of beamline 1.4.3 at the Advanced Light Source, which is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. DOE under Contract No. DE-AC02-05CH11231. M.C.S. and D.J. acknowledge support by the Resnick Institute, and W.S.W. acknowledges support by the National Defense Science and Engineering Graduate Fellowship. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract No. DE-AC02-05CH11231. The authors are grateful to Victor Brar for helpful discussions. \n\nAuthor Contributions: W.S.W. and M.C.S. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1608.02561.pdf

Supplemental Material - nl6b03362_si_001.pdf

", "abstract": "We report measurements of the infrared optical response of thin black phosphorus under field-effect modulation. We interpret the observed spectral changes as a combination of an ambipolar Burstein\u2013Moss (BM) shift of the absorption edge due to band-filling under gate control, and a quantum confined Franz-Keldysh (QCFK) effect, phenomena that have been proposed theoretically to occur for black phosphorus under an applied electric field. Distinct optical responses are observed depending on the flake thickness and starting carrier concentration. Transmission extinction modulation amplitudes of more than two percent are observed, suggesting the potential for use of black phosphorus as an active material in mid-infrared optoelectronic modulator applications.", "date": "2017-01-11", "date_type": "published", "publication": "Nano Letters", "volume": "17", "number": "1", "publisher": "American Chemical Society", "pagerange": "78-84", "id_number": "CaltechAUTHORS:20161114-090220876", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161114-090220876", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.nanolett.6b03362", "primary_object": { "basename": "1608.02561.pdf", "url": "https://authors.library.caltech.edu/records/cpwpy-jvv36/files/1608.02561.pdf" }, "related_objects": [ { "basename": "nl6b03362_si_001.pdf", "url": "https://authors.library.caltech.edu/records/cpwpy-jvv36/files/nl6b03362_si_001.pdf" } ], "pub_year": "2017", "author_list": "Whitney, William S.; Sherrott, Michelle C.; et al." }, { "id": "https://authors.library.caltech.edu/records/x662c-c6529", "eprint_id": 71381, "eprint_status": "archive", "datestamp": "2023-08-19 01:03:58", "lastmod": "2025-04-23 00:50:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Whitney-William-S", "name": { "family": "Whitney", "given": "William S." }, "orcid": "0000-0001-5269-2967" }, { "id": "Brar-Victor-Watson", "name": { "family": "Brar", "given": "Victor Watson" } }, { "id": "Ou-Yunbo", "name": { "family": "Ou", "given": "Yunbo" } }, { "id": "Shao-Yinming", "name": { "family": "Shao", "given": "Yinming" } }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Basov-D-N", "name": { "family": "Basov", "given": "D. N." } }, { "id": "He-Ke", "name": { "family": "He", "given": "Ke" } }, { "id": "Xue-Qi-Kun", "name": { "family": "Xue", "given": "Qi-Kun" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Gate-Variable Mid-Infrared Optical Transitions in a (Bi_(1\u2212x)Sb_x)_2Te_3 Topological Insulator", "ispublished": "pub", "full_text_status": "public", "keywords": "Bismuth antimony telluride, topological insulator, tunable optical properties, mid-infrared, Burstein\u2212Moss shift,\noptical modulator", "note": "\u00a9 2016 American Chemical Society. \n\nPublication Date (Web): December 12, 2016. \n\nThe authors gratefully acknowledge support from the Department of Energy, Office of Science under Grant DE-FG02-07ER46405 and for facilities of the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (DE-SC0001293). W.S.W. also acknowledges support from an NDSEG Graduate Research Fellowship. A.R.D acknowledges fellowship support from the Resnick Institute and the Kavli Nanoscience Institute at Caltech. The authors are grateful to Prof. George Rossman for helpful discussions and use of his FTIR facilities. Author Contributions: W.S.W., V.W.B and H.A.A. conceived the ideas. Y.O. grew the films and W.S.W. fabricated the devices. W.S.W, Y.S. and Y.O. performed measurements. W.S.W and A.R.D calculated the optical model. All authors contributed to writing the paper. D.N.B, K.H., Q.K.X., and H.A.A. supervised the project. \n\nThe authors declare no competing financial interests.\n\n

Accepted Version - acs_2Enanolett_2E6b03992.pdf

Submitted - 1607.03844.pdf

Supplemental Material - nl6b03992_si_001.pdf

", "abstract": "We report mid-infrared spectroscopy measurements of ultrathin, electrostatically gated (Bi_(1-x)Sb_x)_2Te_3 topological insulator films, in which we observe several percent modulation of transmittance and reflectance as gating shifts the Fermi level. Infrared transmittance measurements of gated films were enabled by use of an epitaxial lift-off method for large-area transfer of topological insulator films from infrared-absorbing SrTiO3 growth substrates to thermal oxidized silicon substrates. We combine these optical experiments with transport measurements and angle-resolved photoemission spectroscopy to identify the observed spectral modulation as a gate-driven transfer of spectral weight between both bulk and 2D topological surface channels and interband and intraband channels. We develop a model for the complex permittivity of gated (Bi_(1-x)Sb_x)_2Te_3, and find a good match to our experimental data. These results open the path for layered topological insulator materials as a new candidate for tunable, ultrathin infrared optics and highlight the possibility of switching topological optoelectronic phenomena between bulk and spin-polarized surface regimes.", "date": "2017-01-11", "date_type": "published", "publication": "Nano Letters", "volume": "17", "number": "1", "publisher": "American Chemical Society", "pagerange": "255-260", "id_number": "CaltechAUTHORS:20161024-104047478", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161024-104047478", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Caltech" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acs.nanolett.6b03992", "primary_object": { "basename": "1607.03844.pdf", "url": "https://authors.library.caltech.edu/records/x662c-c6529/files/1607.03844.pdf" }, "related_objects": [ { "basename": "acs_2Enanolett_2E6b03992.pdf", "url": "https://authors.library.caltech.edu/records/x662c-c6529/files/acs_2Enanolett_2E6b03992.pdf" }, { "basename": "nl6b03992_si_001.pdf", "url": "https://authors.library.caltech.edu/records/x662c-c6529/files/nl6b03992_si_001.pdf" } ], "pub_year": "2017", "author_list": "Whitney, William S.; Brar, Victor Watson; et al." }, { "id": "https://authors.library.caltech.edu/records/hc1fy-1t885", "eprint_id": 73427, "eprint_status": "archive", "datestamp": "2023-08-19 00:48:04", "lastmod": "2023-10-24 15:20:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xu-Yunjian", "name": { "family": "Xu", "given": "Yunjian" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "An Efficient and Incentive Compatible Mechanism for Wholesale Electricity Markets", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Locational marginal pricing (LMP), power networks, Vickrey\u2013Clarke\u2013Groves (VCG) mechanism, wholesale electricity markets", "note": "\u00a9 2015 IEEE. \n\nManuscript received January 13, 2015; revised April 24, 2015 and July 14, 2015; accepted September 23, 2015. Date of publication October 13, 2015; date of current version December 21, 2016. \n\nThis work was supported in part by the Massachusetts Institute of Technology-Singapore University of Technology and Design International Design Center under Grant IDG21400103, in part by the National Science Foundation (NSF) NetSE under Grant CNS-0911041, in part by the NSF as part of the NSF/Department of Homeland Security/Department of Transportation/National Aeronautics and Space Administration/National Institutes of Health Cyber-Physical Systems Program under Grant 1545096, in part by the Advanced Research Projects Agency-Energy under Grant DE-AR0000226, in part by the Southern California Edison, in part by the Skotech grant, and in part by the Resnick\nInstitute. Paper no. TSG-00046-2015.", "abstract": "Being widely used in many deregulated wholesale electricity markets, the locational marginal pricing (LMP) mechanism is known to achieve social optimality in a competitive market. When profit-maximizing generators act strategically to manipulate prices; however, LMP may lead to high loss of economic efficiency. In this paper, we apply the Vickrey-Clarke\u2013Groves (VCG) mechanism to wholesale electricity markets. We show that the VCG mechanism minimizes the total cost at a truth-telling dominant strategy equilibrium. We establish an important comparative result that the VCG mechanism always results in higher per-unit electricity prices than the LMP mechanism under any given set of reported supply curves. Numerical results show that the difference between the per-unit prices resulting from the two mechanisms is negligibly small (about 4%) in the IEEE 14-bus and 30-bus test systems. Finally, we apply the VCG mechanism to a day-ahead setting with start-up cost (of conventional generators) and intermittent renewable generation. We show that the VCG mechanism induces the truth-telling behavior of conventional generators in dominant strategies and yields each conventional generator a non-negative expected profit.", "date": "2017-01", "date_type": "published", "publication": "IEEE Transactions on Smart Grid", "volume": "8", "number": "1", "publisher": "IEEE", "pagerange": "128-138", "id_number": "CaltechAUTHORS:20170111-125209937", "issn": "1949-3053", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170111-125209937", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Massachusetts Institute of Technology-Singapore University of Technology and Design International Design Center", "grant_number": "IDG21400103" }, { "agency": "NSF NetSE", "grant_number": "CNS-0911041" }, { "agency": "NSF", "grant_number": "CNS-1545096" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "Skotech" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TSG.2015.2483523", "pub_year": "2017", "author_list": "Xu, Yunjian and Low, Steven H." }, { "id": "https://authors.library.caltech.edu/records/acc7x-v6v86", "eprint_id": 71542, "eprint_status": "archive", "datestamp": "2023-08-19 00:46:12", "lastmod": "2023-10-23 15:53:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wiedenhofer-D", "name": { "family": "Wiedenhofer", "given": "Dominik" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Meng-Jing", "name": { "family": "Meng", "given": "Jing" }, "orcid": "0000-0002-9069-8988" }, { "id": "Zhang-Ning", "name": { "family": "Zhang", "given": "Ning" } }, { "id": "Wei-Yi-Ming", "name": { "family": "Wei", "given": "Yi-Ming" } } ] }, "title": "Unequal household carbon footprints in China", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Macmillan Publishers Limited. \n\nReceived 29 April 2016; accepted 27 October 2016; published online 19 December 2016. \n\nThis work was supported by National Key R&D Program of China (2016YFA0602603 and 2016YFA0602604), the National Natural Science Foundation of China (41629501, 71521002, 41461118, 41501605), Austrian National Science funded project 'MISO\u2014modelling the global metabolic transition' (P27590), the UK Economic and Social Research Council funded project 'Dynamics of Green Growth in European and Chinese Cities' (ES/L016028/1), the UK Natural Environment Research Council funded project 'Integrated assessment of the emission-health-socioeconomics nexus and air pollution mitigation solutions and interventions in Beijing' (NE/N00714X/1). Many thanks go to J. Minx, F. Krausmann and J. K. Steinberger for their feedback on the manuscript, to G. Peters for support with the global emissions data set for the GTAP-MRIO and to L. Yu for his feedback on the concordances to bridge the GTAP-MRIO and the Chinese national IOTs classifications. \n\nAuthor Contributions: D.W. and D.G. designed the research, performed calculations and discussed the results. D.W. wrote the paper. D.G., Z.L., J.M., N.Z. and Y.-M.W. collected data and contributed to writing the paper. \n\nThe authors declare no competing financial interests.\n\n

Supplemental Material - nclimate3165-s1.pdf

", "abstract": "Households' carbon footprints are unequally distributed among the rich and poor due to differences in the scale and patterns of consumption. We present distributional focused carbon footprints for Chinese households and use a carbon-footprint-Gini coefficient to quantify inequalities. We find that in 2012 the urban very rich, comprising 5% of population, induced 19% of the total carbon footprint from household consumption in China, with 6.4 tCO_2/cap. The average Chinese household footprint remains comparatively low (1.7 tCO_2/cap), while those of the rural population and urban poor, comprising 58% of population, are 0.5\u20131.6 tCO_2/cap. Between 2007 and 2012 the total footprint from households increased by 19%, with 75% of the increase due to growing consumption of the urban middle class and the rich. This suggests that a transformation of Chinese lifestyles away from the current trajectory of carbon-intensive consumption patterns requires policy interventions to improve living standards and encourage sustainable consumption.", "date": "2017-01", "date_type": "published", "publication": "Nature Climate Change", "volume": "7", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "75-80", "id_number": "CaltechAUTHORS:20161027-112645545", "issn": "1758-678X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161027-112645545", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Basic Research Program of China", "grant_number": "2016YFA0602603" }, { "agency": "National Key Basic Research Program of China", "grant_number": "2016YFA0602604" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41629501" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71521002" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41461118" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41501605" }, { "agency": "FWF Der Wissenschaftsfonds", "grant_number": "P27590" }, { "agency": "Economic and Social Research Council (ESRC)", "grant_number": "ES/L016028/1" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/N00714X/1" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nclimate3165", "primary_object": { "basename": "nclimate3165-s1.pdf", "url": "https://authors.library.caltech.edu/records/acc7x-v6v86/files/nclimate3165-s1.pdf" }, "pub_year": "2017", "author_list": "Wiedenhofer, Dominik; Guan, Dabo; et al." }, { "id": "https://authors.library.caltech.edu/records/j0gjv-1rp69", "eprint_id": 73314, "eprint_status": "archive", "datestamp": "2023-08-22 19:18:27", "lastmod": "2023-10-24 15:13:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Hongyan", "name": { "family": "Zhao", "given": "Hongyan" } }, { "id": "Zhang-Qiang", "name": { "family": "Zhang", "given": "Qiang" }, "orcid": "0000-0002-8376-131X" }, { "id": "Huo-Hong", "name": { "family": "Huo", "given": "Hong" } }, { "id": "Lin-Jintai", "name": { "family": "Lin", "given": "Jintai" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Wang-Haikun", "name": { "family": "Wang", "given": "Haikun" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "He-Kebin", "name": { "family": "He", "given": "Kebin" } } ] }, "title": "Environment-economy tradeoff for Beijing-Tianjin-Hebei's exports", "ispublished": "pub", "full_text_status": "public", "keywords": "BTH; Exports; Pollutant emissions; CO2; Value added", "note": "\u00a9 2016 Elsevier Ltd. \n\nReceived 30 January 2016, Revised 8 April 2016, Accepted 10 April 2016, Available online 19 April 2016.", "abstract": "The trade of goods among regions or nations associated with large environmental consequences. Yet balancing economic gains and environmental consequences induced by trade is still hindered by a lack of quantification of these two factors, especially for the environmental problems those are more locally oriented, such as the atmospheric pollution. Based on an environmental input\u2013output analysis for 2010, we contrast economic gains (value added) against atmospheric pollutant emissions (sulfur dioxide (SO_2), nitric oxide (NO_x), primary fine particulate matter (PM_(2.5)) and non-methane volatile organic compounds (NMVOC)) and the widely concerned CO2 emissions associated with international and interprovincial exports from Beijing\u2013Tianjin\u2013Hebei (BTH), the most polluted area in China. Our results show that exports contributed 55\u201362% of BTH's production emissions and 54% of its total value added. BTH's large exports of metals and metal products, nonmetal mineral products, chemical and transportation and warehousing, generated a larger share of pollutant emissions (36\u201346% of BTH's total) than that of value added (17%) along the supply chain. Most of BTH's embodied emissions in exports go to neighboring provinces and the developed east coastal regions in China, although the economic returns are comparatively low. Among BTH, industrial production in Beijing and Tianjin lead to more pollutant emission than value added in Hebei, due to reliance on pollution-intensive product imports from Hebei. Our results call for refocusing and restructuring of BTH's industry and trade structures to balance the economic gains and environmental losses for each region.", "date": "2016-12-15", "date_type": "published", "publication": "Applied Energy", "volume": "184", "publisher": "Elsevier", "pagerange": "926-935", "id_number": "CaltechAUTHORS:20170106-151334790", "issn": "0306-2619", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170106-151334790", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apenergy.2016.04.038", "pub_year": "2016", "author_list": "Zhao, Hongyan; Zhang, Qiang; et al." }, { "id": "https://authors.library.caltech.edu/records/pm879-25q28", "eprint_id": 73313, "eprint_status": "archive", "datestamp": "2023-08-19 00:33:51", "lastmod": "2023-10-24 15:13:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Feng-Kuishuang", "name": { "family": "Feng", "given": "Kuishuang" }, "orcid": "0000-0001-5139-444X" }, { "id": "Davis-S-J", "name": { "family": "Davis", "given": "Steven J." }, "orcid": "0000-0002-9338-0844" }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Chen-Bin", "name": { "family": "Chen", "given": "Bin" } }, { "id": "Hubacek-K", "name": { "family": "Hubacek", "given": "Klaus" }, "orcid": "0000-0003-2561-6090" }, { "id": "Yan-Jinyue", "name": { "family": "Yan", "given": "Jinyue" } } ] }, "title": "Understanding the energy consumption and greenhouse gas emissions and the implication for achieving climate change mitigation targets", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Elsevier Ltd. \n\nAvailable online 9 November 2016.", "abstract": "[No abstract]", "date": "2016-12-15", "date_type": "published", "publication": "Applied Energy", "volume": "184", "publisher": "Elsevier", "pagerange": "737-741", "id_number": "CaltechAUTHORS:20170106-151046477", "issn": "0306-2619", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170106-151046477", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apenergy.2016.10.110", "pub_year": "2016", "author_list": "Liu, Zhu; Feng, Kuishuang; et al." }, { "id": "https://authors.library.caltech.edu/records/9zswx-ggw49", "eprint_id": 73258, "eprint_status": "archive", "datestamp": "2023-08-22 19:18:21", "lastmod": "2023-10-24 15:10:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mi-Zhifu", "name": { "family": "Mi", "given": "Zhifu" }, "orcid": "0000-0001-8106-0694" }, { "id": "Zhang-Yunkun", "name": { "family": "Zhang", "given": "Yunkun" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Shan-Yuli", "name": { "family": "Shan", "given": "Yuli" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Cong-Ronggang", "name": { "family": "Cong", "given": "Ronggang" } }, { "id": "Yuan-Xiao-Chen", "name": { "family": "Yuan", "given": "Xiao-Chen" } }, { "id": "Wei-Yi-Ming", "name": { "family": "Wei", "given": "Yi-Ming" } } ] }, "title": "Consumption-based emission accounting for Chinese cities", "ispublished": "pub", "full_text_status": "public", "keywords": "Consumption-based accounting; Production-based emissions; Embodied emissions; Input-output analysis; Carbon footprint; City", "note": "\u00a9 2016 Elsevier Ltd. \n\nReceived 28 March 2016, Revised 13 June 2016, Accepted 18 June 2016, Available online 23 June 2016.", "abstract": "Most of China's CO_2 emissions are related to energy consumption in its cities. Thus, cities are critical for implementing China's carbon emissions mitigation policies. In this study, we employ an input-output model to calculate consumption-based CO_2 emissions for thirteen Chinese cities and find substantial differences between production- and consumption-based accounting in terms of both overall and per capita carbon emissions. Urban consumption not only leads to carbon emissions within a city's own boundaries but also induces emissions in other regions via interregional trade. In megacities such as Shanghai, Beijing and Tianjin, approximately 70% of consumption-based emissions are imported from other regions. Annual per capita consumption-based emissions in the three megacities are 14, 12 and 10 tonnes of CO_2 per person, respectively. Some medium-sized cities, such as Shenyang, Dalian and Ningbo, exhibit per capita emissions that resemble those in Tianjin. From the perspective of final use, capital formation is the largest contributor to consumption-based emissions at 32\u201365%. All thirteen cities are categorized by their trading patterns: five are production-based cities in which production-based emissions exceed consumption-based emissions, whereas eight are consumption-based cities, with the opposite emissions pattern. Moreover, production-based cities tend to become consumption-based as they undergo socioeconomic development.", "date": "2016-12-15", "date_type": "published", "publication": "Applied Energy", "volume": "184", "publisher": "Elsevier", "pagerange": "1073-1081", "id_number": "CaltechAUTHORS:20170105-092421877", "issn": "0306-2619", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170105-092421877", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apenergy.2016.06.094", "pub_year": "2016", "author_list": "Mi, Zhifu; Zhang, Yunkun; et al." }, { "id": "https://authors.library.caltech.edu/records/x5zxk-77a93", "eprint_id": 73259, "eprint_status": "archive", "datestamp": "2023-08-22 19:18:24", "lastmod": "2023-10-24 15:10:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shan-Yuli", "name": { "family": "Shan", "given": "Yuli" } }, { "id": "Liu-Jianghua", "name": { "family": "Liu", "given": "Jianghua" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Xu-Xinwanghao", "name": { "family": "Xu", "given": "Xinwanghao" } }, { "id": "Shao-Shuai", "name": { "family": "Shao", "given": "Shuai" }, "orcid": "0000-0002-9525-6310" }, { "id": "Wang-Peng", "name": { "family": "Wang", "given": "Peng" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } } ] }, "title": "New provincial CO_2 emission inventories in China based on apparent energy consumption data and updated emission factors", "ispublished": "pub", "full_text_status": "public", "keywords": "CO_2 emissions accounting; Emissions socioeconomics; Energy flows; Chinese provinces", "note": "\u00a9 2016 Elsevier Ltd. \n\nReceived 12 December 2015, Revised 28 February 2016, Accepted 17 March 2016, Available online 24 March 2016.", "abstract": "This study employs \"apparent energy consumption\" approach and updated emissions factors to re-calculate Chinese provincial CO_2 emissions during 2000\u20132012 to reduce the uncertainty in Chinese CO_2 emission estimates for the first time. The study presents the changing emission-socioeconomic features of each provinces as well. The results indicate that Chinese provincial aggregated CO_2 emissions calculated by the apparent energy consumption and updated emissions factors are coincident with the national emissions estimated by the same approach, which are 12.69% smaller than the one calculated by the traditional approach and IPCC default emission factors. The provincial aggregated CO_2 emissions increased from 3160 million tonnes in 2000 to 8583 million tonnes in 2012. During the period, Shandong province contributed most to national emissions accumulatively (with an average percentage of 10.35%), followed by Liaoning (6.69%), Hebei (6.69%) and Shanxi provinces (6.25%). Most of the CO_2 emissions were from raw coal, which is primarily burned in the thermal power sector. The analyses of per capita emissions and emission intensity in 2012 indicates that provinces located in the northwest and north had higher per capita CO_2 emissions and emission intensities than the central and southeast coastal regions. Understanding the emissions and emission-socioeconomic characteristics of different provinces is critical for developing mitigation strategies.", "date": "2016-12-15", "date_type": "published", "publication": "Applied Energy", "volume": "184", "publisher": "Elsevier", "pagerange": "742-750", "id_number": "CaltechAUTHORS:20170105-092809284", "issn": "0306-2619", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170105-092809284", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apenergy.2016.03.073", "pub_year": "2016", "author_list": "Shan, Yuli; Liu, Jianghua; et al." }, { "id": "https://authors.library.caltech.edu/records/th70g-04474", "eprint_id": 72275, "eprint_status": "archive", "datestamp": "2023-08-19 00:32:42", "lastmod": "2023-10-23 20:34:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Schottky-barrier-free contacts with two-dimensional semiconductors by surface-engineered MXenes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: October 17, 2016; Published: November 22, 2016. \n\nY.L. thanks the support from Resnick Prize Postdoctoral Fellowship at Caltech. This research was funded by DOE DESC0014607. This work used computational resources sponsored by the DOE's Office of Energy Efficiency and Renewable Energy and located at the National Renewable Energy Laboratory; the Extreme Science and Engineering Discovery Environment (XSEDE; supported by NSF Grant ACI-1053575); and the National Energy Research Scientific Computing Center (NERSC; a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract DE-AC02-05CH11231). \n\nThe authors declare no competing financial interests.\n\n

Supplemental Material - ja6b10834_si_001.pdf

", "abstract": "Two-dimensional (2D) metal carbides and nitrides, called MXenes, have attracted great interest for applications such as energy storage. Here we demonstrate their potential as Schottky-barrier-free metal contacts to 2D semiconductors, providing a solution to the contact-resistance problem in 2D electronics. Based on first principles calculations, we find that the surface chemistry strongly affects the Fermi level of MXenes: O termination always increases the work function with respect to that of bare surface, OH always decreases it, while F exhibits either trend depending on the specific material. This phenomenon originates from the effect of surface dipoles, which together with the weak Fermi level pinning, enable Schottky-barrier-free hole (or electron) injection into 2D semiconductors through van der Waals junctions with some of the O-terminated (or all the OH-terminated) MXenes. Furthermore, we suggest synthetic routes to control the surface terminations based on the calculated formation energies. This study enhances the understanding of the correlation between surface chemistry and electronic/transport properties of 2D materials, and also gives practical predictions for improving 2D electronics.", "date": "2016-12-14", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "49", "publisher": "American Chemical Society", "pagerange": "15853-15856", "id_number": "CaltechAUTHORS:20161123-091514649", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161123-091514649", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014607" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/jacs.6b10834", "primary_object": { "basename": "ja6b10834_si_001.pdf", "url": "https://authors.library.caltech.edu/records/th70g-04474/files/ja6b10834_si_001.pdf" }, "pub_year": "2016", "author_list": "Liu, Yuanyue; Xiao, Hai; et al." }, { "id": "https://authors.library.caltech.edu/records/caz0w-xej53", "eprint_id": 72406, "eprint_status": "archive", "datestamp": "2023-08-19 00:13:56", "lastmod": "2023-10-23 22:31:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xi-Fengming", "name": { "family": "Xi", "given": "Fengming" } }, { "id": "Davis-S-J", "name": { "family": "Davis", "given": "Steven J." }, "orcid": "0000-0002-9338-0844" }, { "id": "Ciais-P", "name": { "family": "Ciais", "given": "Philippe" }, "orcid": "0000-0001-8560-4943" }, { "id": "Crawford-Brown-D", "name": { "family": "Crawford-Brown", "given": "Douglas" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Pade-C", "name": { "family": "Pade", "given": "Claus" } }, { "id": "Shi-Tiemao", "name": { "family": "Shi", "given": "Tiemao" } }, { "id": "Syddall-M", "name": { "family": "Syddall", "given": "Mark" } }, { "id": "Lv-Jie", "name": { "family": "Lv", "given": "Jie" } }, { "id": "Ji-Lanzhu", "name": { "family": "Ji", "given": "Lanzhu" } }, { "id": "Bing-Longfei", "name": { "family": "Bing", "given": "Longfei" } }, { "id": "Wang-Jiaoyue", "name": { "family": "Wang", "given": "Jiaoyue" } }, { "id": "Wei-Wei", "name": { "family": "Wei", "given": "Wei" }, "orcid": "0000-0002-1018-7708" }, { "id": "Yang-Keun-Hyeok", "name": { "family": "Yang", "given": "Keun-Hyeok" } }, { "id": "Lagerblad-B", "name": { "family": "Lagerblad", "given": "Bj\u00f6rn" } }, { "id": "Galan-I", "name": { "family": "Galan", "given": "Isabel" } }, { "id": "Andrade-C", "name": { "family": "Andrade", "given": "Carmen" } }, { "id": "Zhang-Ying", "name": { "family": "Zhang", "given": "Ying" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" } ] }, "title": "Substantial global carbon uptake by cement carbonation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Macmillan Publishers Limited. \n\nReceived 17 July 2016; accepted 10 October 2016; published online 21 November 2016. \n\nSupported by the NSFC (41473076, 41501605, 51578344, 31100346, 41629501, 71533005), Fund of Youth Innovation Promotion Association, Chinese Academy of Sciences, Fund of Fellowships for Young International Distinguished Scientists in Institute of Applied Ecology, Chinese Academy of Sciences, National Key R&D Program of China (2016YFA0602604), the UK Economic and Social Research Council funded project 'Dynamics of Green Growth in European and Chinese Cities' (ES/L016028/1), and the UK Natural Environment Research Council funded project 'Integrated assessment of the emission-health-socioeconomics nexus and air pollution mitigation solutions and interventions in Beijing' (NE/N00714X/1). \n\nAuthor Contributions:\nF.X. and Z.L. designed the paper. F.X. conceived the research. F.X., C.P., T.S., J.W., K.H.Y., L.B., I.G., C.A. and P.C. provided the data from different countries and regions. T.S., F.X., J.W. and Y.Z. provided the survey statistics and experimental measurements data. S.J.D., F.X., Z.L., P.C., M.S. and D.C.B. performed the analysis. C.P., J.L., Z.L., L.J., P.C., K.H.Y., L.B., I.G. and Y.Z. provided the reference data. F.X., L.B., D.C.B., Z.L. M.S. and T.S. performed uncertainty analysis. S.J.D. and L.B. drew the figures. All authors contributed to writing the paper. \n\nData availability. The authors declare that the data supporting the findings of this study are available within the Article and its Supplementary Information files. \n\nThe authors declare no competing financial interests.\n\n

Supplemental Material - ngeo2840-s1.pdf

Supplemental Material - ngeo2840-s2.xlsx

", "abstract": "Calcination of carbonate rocks during the manufacture of cement produced 5% of global CO_2 emissions from all industrial process and fossil-fuel combustion in 2013. Considerable attention has been paid to quantifying these industrial process emissions from cement production, but the natural reversal of the process\u2014carbonation\u2014has received little attention in carbon cycle studies. Here, we use new and existing data on cement materials during cement service life, demolition, and secondary use of concrete waste to estimate regional and global CO_2 uptake between 1930 and 2013 using an analytical model describing carbonation chemistry. We find that carbonation of cement materials over their life cycle represents a large and growing net sink of CO_2, increasing from 0.10 GtC yr^(\u22121) in 1998 to 0.25 GtC yr^(\u22121) in 2013. In total, we estimate that a cumulative amount of 4.5 GtC has been sequestered in carbonating cement materials from 1930 to 2013, offsetting 43% of the CO_2 emissions from production of cement over the same period, not including emissions associated with fossil use during cement production. We conclude that carbonation of cement products represents a substantial carbon sink that is not currently considered in emissions inventories.", "date": "2016-12", "date_type": "published", "publication": "Nature Geoscience", "volume": "9", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "880-883", "id_number": "CaltechAUTHORS:20161129-114953242", "issn": "1752-0894", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161129-114953242", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41473076" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41501605" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51578344" }, { "agency": "National Natural Science Foundation of China", "grant_number": "31100346" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41629501" }, { "agency": "National Natural Science Foundation of China", "grant_number": "71533005" }, { "agency": "Fund of Youth Innovation Promotion Association" }, { "agency": "Chinese Academy of Sciences" }, { "agency": "Fund of Fellowships for Young International Distinguished Scientists in Institute of Applied Ecology" }, { "agency": "National Key Basic Research Program of China", "grant_number": "2016YFA0602604" }, { "agency": "Economic and Social Research Council", "grant_number": "ES/L016028/1" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/N00714X/1" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/ngeo2840", "primary_object": { "basename": "ngeo2840-s1.pdf", "url": "https://authors.library.caltech.edu/records/caz0w-xej53/files/ngeo2840-s1.pdf" }, "related_objects": [ { "basename": "ngeo2840-s2.xlsx", "url": "https://authors.library.caltech.edu/records/caz0w-xej53/files/ngeo2840-s2.xlsx" } ], "pub_year": "2016", "author_list": "Xi, Fengming; Davis, Steven J.; et al." }, { "id": "https://authors.library.caltech.edu/records/s5dxq-rk946", "eprint_id": 71730, "eprint_status": "archive", "datestamp": "2023-08-19 00:09:39", "lastmod": "2023-10-20 23:25:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hunter-B-M", "name": { "family": "Hunter", "given": "Bryan M." }, "orcid": "0000-0001-8559-9304" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "M\u00fcller-A-M", "name": { "family": "M\u00fcller", "given": "Astrid M." }, "orcid": "0000-0002-2785-6808" } ] }, "title": "Earth-Abundant Heterogeneous Water Oxidation Catalysts", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: June 23, 2016. Publication Date (Web): October 31, 2016. \n\nWe thank Dave Britt and Troy Stich for helpful discussions. Research was performed in the Laser Resource Center and the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. The NSF CCI Solar Fuels Program (CHE-1305124) and the Arnold and Mabel Beckman Foundation supported this work. B.M.H. is a fellow of the Resnick Sustainability Institute at Caltech.", "abstract": "Water oxidation is a key chemical transformation for the conversion of solar energy into chemical fuels. Our review focuses on recent work on robust earth-abundant heterogeneous catalysts for the oxygen-evolving reaction (OER). We point out that improvements in the performance of OER catalysts will depend critically on the success of work aimed at understanding reaction barriers based on atomic-level mechanisms. We highlight the challenge of obtaining acid-stable OER catalysts, with proposals for elements that could be employed to reach this goal. We suggest that future advances in solar fuels science will be accelerated by the development of new methods for materials synthesis and characterization, along with in-depth investigations of redox mechanisms at catalytic surfaces.", "date": "2016-11-23", "date_type": "published", "publication": "Chemical Reviews", "volume": "116", "number": "22", "publisher": "American Chemical Society", "pagerange": "14120-14136", "id_number": "CaltechAUTHORS:20161104-074948999", "issn": "0009-2665", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161104-074948999", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemrev.6b00398", "pub_year": "2016", "author_list": "Hunter, Bryan M.; Gray, Harry B.; et al." }, { "id": "https://authors.library.caltech.edu/records/hrvny-6be42", "eprint_id": 71983, "eprint_status": "archive", "datestamp": "2023-08-19 00:05:30", "lastmod": "2023-10-23 17:44:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Betz-K-N", "name": { "family": "Betz", "given": "Kerry N." }, "orcid": "0000-0001-9118-5909" }, { "id": "Haibach-M-C", "name": { "family": "Haibach", "given": "Michael C." }, "orcid": "0000-0001-8383-5633" }, { "id": "Romine-A-M", "name": { "family": "Romine", "given": "Andrew M." }, "orcid": "0000-0002-6703-2926" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Sodium Hydroxide Catalyzed Dehydrocoupling of Alcohols with Hydrosilanes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: June 10, 2016; Revised: October 11, 2016; Publication Date (Web): November 9, 2016. \n\nThis work was supported by the NSF under the CCI Center for Selective C\u2013H Functionalization (CHE-1205646) and under CHE-1212767. A.A.T. is grateful to the Resnick Sustainability Institute at Caltech and to Dow Chemical for a predoctoral fellowship and to NSERC for a PGS D fellowship. We thank S. Virgil and the Caltech Center for Catalysis and Chemical Synthesis for access to analytical equipment. M. Shahgoli and N. Torian (Caltech) are acknowledged for assistance with high-resolution mass spectrometry. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ol6b01687_si_001.pdf

", "abstract": "An O\u2013Si bond construction protocol employing abundantly available and inexpensive NaOH as the catalyst is described. The method enables the cross-dehydrogenative coupling of an alcohol and hydrosilane to directly generate the corresponding silyl ether under mild conditions and without the production of stoichiometric salt byproducts. The scope of both coupling partners is excellent, positioning the method for use in complex molecule and materials science applications. A novel Si-based cross-coupling reagent is also reported.", "date": "2016-11-18", "date_type": "published", "publication": "Organic Letters", "volume": "18", "number": "22", "publisher": "American Chemical Society", "pagerange": "5776-5779", "id_number": "CaltechAUTHORS:20161114-093917870", "issn": "1523-7060", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161114-093917870", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.orglett.6b01687", "primary_object": { "basename": "ol6b01687_si_001.pdf", "url": "https://authors.library.caltech.edu/records/hrvny-6be42/files/ol6b01687_si_001.pdf" }, "pub_year": "2016", "author_list": "Toutov, Anton A.; Betz, Kerry N.; et al." }, { "id": "https://authors.library.caltech.edu/records/kdyj6-gva30", "eprint_id": 70765, "eprint_status": "archive", "datestamp": "2023-08-20 14:12:59", "lastmod": "2023-10-20 23:29:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Solar-Driven Reduction of 1 atm of CO_2 to Formate at 10% Energy-Conversion Efficiency by Use of a TiO_2-Protected III\u2013V Tandem Photoanode in Conjunction with a Bipolar Membrane and a Pd/C Cathode", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: August 2, 2016; Accepted: September 9, 2016; Publication Date (Web): September 9, 2016. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. The authors also thank N. Dalleska (Caltech) for his assistance with measurements and analysis of the ICPMS and TIC data. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - nz6b00317_si_001.pdf

", "abstract": "A solar-driven CO_2 reduction (CO_2R) cell was constructed, consisting of a tandem GaAs/InGaP/TiO_2/Ni photoanode in 1.0 M KOH(aq) (pH = 13.7) to facilitate the oxygen-evolution reaction (OER), a Pd/C nanoparticle-coated Ti mesh cathode in 2.8 M KHCO_3(aq) (pH = 8.0) to perform the CO_2R reaction, and a bipolar membrane to allow for steady-state operation of the catholyte and anolyte at different bulk pH values. At the operational current density of 8.5 mA cm^(\u20132), in 2.8 M KHCO_3(aq), the cathode exhibited <100 mV overpotential and >94% Faradaic efficiency for the reduction of 1 atm of CO_2(g) to formate. The anode exhibited a 320 \u00b1 7 mV overpotential for the OER in 1.0 M KOH(aq), and the bipolar membrane exhibited \u223c480 mV voltage loss with minimal product crossovers and >90 and >95% selectivity for protons and hydroxide ions, respectively. The bipolar membrane facilitated coupling between two electrodes and electrolytes, one for the CO_2R reaction and one for the OER, that typically operate at mutually different pH values and produced a lower total cell overvoltage than known single-electrolyte CO_2R systems while exhibiting \u223c10% solar-to-fuels energy-conversion efficiency.", "date": "2016-10-14", "date_type": "published", "publication": "ACS Energy Letters", "volume": "1", "number": "4", "publisher": "American Chemical Society", "pagerange": "764-770", "id_number": "CaltechAUTHORS:20161003-141800305", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161003-141800305", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.6b00317", "primary_object": { "basename": "nz6b00317_si_001.pdf", "url": "https://authors.library.caltech.edu/records/kdyj6-gva30/files/nz6b00317_si_001.pdf" }, "pub_year": "2016", "author_list": "Zhou, Xinghao; Liu, Rui; et al." }, { "id": "https://authors.library.caltech.edu/records/m5556-fy940", "eprint_id": 70140, "eprint_status": "archive", "datestamp": "2023-08-20 14:10:02", "lastmod": "2025-04-26 02:58:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johnson-S-I", "name": { "family": "Johnson", "given": "Samantha I." } }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Selectivity for HCO\u2082^\u2013 over H\u2082 in the Electrochemical Catalytic Reduction of CO\u2082 by (POCOP)IrH\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "density functional theory, electrochemical CO2 reduction, reaction mechanism, chemoselectivity, hydricity, hydrogen evolution", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: June 21, 2016; Revised: August 10, 2016; Publication Date (Web): August 15, 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.I.J. is supported by a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469 and by the generous support of the Resnick Sustainability Institute. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cs6b01755_si_001.pdf

Supplemental Material - cs6b01755_si_002.xyz

", "abstract": "It has been demonstrated experimentally that electrochemical CO_2 reduction catalyzed by (POCOP)IrH_2 ([C_6H_3-2,6-[OP(tBu)_2]_2]IrH_2) produces formate without significant H_2. We use first-principles density functional theory (M06) including Poisson\u2013Boltzmann solvation to determine the detailed atomistic mechanism and illuminate strategies for designing formate-selective catalysts. A mechanism involving hydride transfer from Ir^(III) dihydride explains the selectivity for formate over H_2 and is corroborated by reduction potential (irreversible reduction of (POCOP)Ir(H)(NCMe)_2^+ at ca. \u22121.3 V vs NHE, in comparison to \u22121.31 V vs NHE calculated for one-electron reduction of Ir^(III)(H)(NCMe)_2^+) and turnover frequency. We find that several thermodynamically favorable pathways exist for the hydrogen evolution reaction (HER) from both Ir^(III)(H)_2 and Ir^I\u2013H^\u2013 but are kinetically hindered, posing computed activation barriers above 25 kcal/mol at pH 7. However, with formate or bicarbonate acting as cocatalyst, the barriers are lowered to 18.8 kcal/mol. The preference of (POCOP)Ir to form a dihydride instead of a dihydrogen adduct also disfavors the HER and facilitates catalyst regeneration. In contrast, substituting cobalt for iridium raises the barrier for hydride transfer to CO_2 by 12.0 kcal/mol and lowers the required reduction potential to \u22121.65 V vs NHE. Calculated driving forces for hydride transfer from Ir^I and Ir^(III) intermediates illustrate different strategies for positioning the hydricity relative to the thermodynamic hydricities of H_2/H^+ and HCOO^\u2013/CO_2. The data support an approach of selecting a hydricity that is just thermodynamically able to reduce CO_2. The effect of solvation on calculated driving forces for hydride transfer is also discussed.", "date": "2016-10-07", "date_type": "published", "publication": "ACS Catalysis", "volume": "6", "number": "10", "publisher": "American Chemical Society", "pagerange": "6362-6371", "id_number": "CaltechAUTHORS:20160902-085020686", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160902-085020686", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.6b01755", "primary_object": { "basename": "cs6b01755_si_001.pdf", "url": "https://authors.library.caltech.edu/records/m5556-fy940/files/cs6b01755_si_001.pdf" }, "related_objects": [ { "basename": "cs6b01755_si_002.xyz", "url": "https://authors.library.caltech.edu/records/m5556-fy940/files/cs6b01755_si_002.xyz" } ], "pub_year": "2016", "author_list": "Johnson, Samantha I.; Nielsen, Robert J.; et al." }, { "id": "https://authors.library.caltech.edu/records/g0g5n-k0628", "eprint_id": 69086, "eprint_status": "archive", "datestamp": "2023-08-20 13:53:41", "lastmod": "2025-04-23 15:28:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Jermyn-A-S", "name": { "family": "Jermyn", "given": "Adam S." }, "orcid": "0000-0001-5048-9973" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Cubic Nonlinearity Driven Up-Conversion in High-Field Plasmonic Hot Carrier Systems", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: April 5, 2016; Revised: June 20, 2016; Publication Date (Web): June 20, 2016. \n\nSpecial Issue: Richard P. Van Duyne Festschrift. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.S.J. acknowledges support from the Barry M. Goldwater Scholarship. The authors acknowledge support from NG NEXT at Northrop Grumman Corporation. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.", "abstract": "Surface plasmon resonances confine electromagnetic fields to the nanoscale, producing high field strengths suitable for exploiting nonlinear optical properties. We examine the prospect of detecting and utilizing one such property in plasmonic metals: the imaginary part of the cubic susceptibility, which corresponds to two plasmons decaying together to produce high energy carriers. Here we present ab initio predictions of the rates and carrier distributions generated by direct interband and phonon-assisted intraband transitions in one and two-plasmon decay. We propose detection of the higher energy carriers generated from two-plasmon decays that are inaccessible in one-plasmon decay as a viable signature of these processes in ultrafast experiments.", "date": "2016-09-22", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "120", "number": "37", "publisher": "American Chemical Society", "pagerange": "21056-21062", "id_number": "CaltechAUTHORS:20160718-092335284", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160718-092335284", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Barry M. Goldwater Scholarship" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.6b03463", "pub_year": "2016", "author_list": "Narang, Prineha; Sundararaman, Ravishankar; et al." }, { "id": "https://authors.library.caltech.edu/records/jswhn-mhn98", "eprint_id": 70426, "eprint_status": "archive", "datestamp": "2023-08-20 13:51:27", "lastmod": "2023-10-20 22:57:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jasper-J-T", "name": { "family": "Jasper", "given": "Justin T." }, "orcid": "0000-0002-2461-5283" }, { "id": "Shafaat-O-S", "name": { "family": "Shafaat", "given": "Oliver S." } }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" } ] }, "title": "Electrochemical Transformation of Trace Organic Contaminants in Latrine Wastewater", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: June 10, 2016; Revised: August 23, 2016; Accepted: August 26, 2016. \n\nThis research was supported by the Bill and Melinda Gates Foundation (BMGF RTTC Grant OPP1111246) and a Resnick Postdoctoral Fellowship to JTJ. \u00b7Cl2\u2013 reaction rate constants were measured in the Beckman Institute Laser Resource Center at the California Institute of Technology with funding provided by the Arnold and Mabel Beckman Foundation. We thank James Barazesh and Cody Finke for useful discussions and critically reviewing the manuscript. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - es6b02912_si_001.pdf

", "abstract": "Solar-powered electrochemical systems have shown promise for onsite wastewater treatment in regions where basic infrastructure for conventional wastewater treatment is not available. To assess the applicability of these systems for trace organic contaminant treatment, test compound electrolysis rate constants were measured in authentic latrine wastewater using mixed-metal oxide anodes coupled with stainless steel cathodes. Complete removal of ranitidine and cimetidine was achieved within 30 min of electrolysis at an applied potential of 3.5 V (0.7 A L^(\u20131)). Removal of acetaminophen, ciprofloxacin, trimethoprim, propranolol, and carbamazepine (>80%) was achieved within 3 h of electrolysis. Oxidation of ranitidine, cimetidine, and ciprofloxacin was primarily attributed to reaction with NH_2Cl. Transformation of trimethoprim, propranolol, and carbamazepine was attributed to direct electron transfer and to reactions with surface-bound reactive chlorine species. Relative contributions of aqueous phase \u00b7OH, \u00b7Cl, \u00b7Cl_2\u2013, HOCl/OCl\u2013, and Cl_2 were determined to be negligible based on measured second-order reaction rate constants, probe compound reaction rates, and experiments in buffered Cl\u2013 solutions. Electrical energy per order of removal (E_(EO)) increased with increasing applied potentials and current densities. Test compound removal was most efficient at elevated Cl\u2013 concentrations present when treated wastewater is recycled for use as flushing water (i.e., \u223c 75 mM Cl\u2013; E_(EO) = 0.2\u20136.9 kWh log^(\u20131) m^(\u20133)). Identified halogenated and oxygenated electrolysis products typically underwent further transformations to unidentifiable products within the 3 h treatment cycle. Identifiable halogenated byproduct formation and accumulation was minimized during electrolysis of wastewater containing 75 mM Cl^\u2013.", "date": "2016-09-20", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "50", "number": "18", "publisher": "American Chemical Society", "pagerange": "10198-10208", "id_number": "CaltechAUTHORS:20160919-104159870", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160919-104159870", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1111246" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Arnold and Mabel Beckman Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.est.6b02912", "primary_object": { "basename": "es6b02912_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jswhn-mhn98/files/es6b02912_si_001.pdf" }, "pub_year": "2016", "author_list": "Jasper, Justin T.; Shafaat, Oliver S.; et al." }, { "id": "https://authors.library.caltech.edu/records/f4pka-t5f58", "eprint_id": 70195, "eprint_status": "archive", "datestamp": "2023-08-22 18:42:19", "lastmod": "2025-04-23 19:57:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jariwala-Deep", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Sherrott-Michelle-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Near-Unity Absorption in van der Waals Semiconductors for Ultrathin Optoelectronics", "ispublished": "pub", "full_text_status": "public", "keywords": "broadband; heterostructures; light trapping; near-unity absorption; photovoltaics; Transition metal dichalcogenides", "note": "\u00a9 2016 American Chemical Society. \n\nPublication Date (Web): August 26, 2016. Received: May 11, 2016. Revised: August 23, 2016. \n\nThis work is part of the \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001293. D.J., A.R.D., and M.C.S. acknowledge additional support from Resnick Sustainability Institute Graduate and Postdoctoral Fellowships. A.R.D. also acknowledges support in part from the Kavli Nanoscience Institute Postdoctoral Fellowship. G.T. acknowledges support in part from the Swiss National Science Foundation, Early Postdoc Mobility Fellowship n.P2EZP2_159101. J.W. acknowledges support from the National Science Foundation Graduate Research Fellowship under Grant No. 1144469. \n\nAuthor Contributions: D.J. prepared the samples and fabricated the devices. A.R.D. performed all the calculations. D.J., G.T., and J.W. performed the electrical and photocurrent measurements. M.C.S. assisted with sample preparation and fabrication. H.A.A. supervised over all the experiments, calculations, and data collection. All authors contributed to data interpretation, presentation, and writing of the manuscript. \n\nThe authors declare no competing financial interest.\n\n

Submitted - 1605.04057.pdf

Supplemental Material - nl6b01914_si_001.pdf

", "abstract": "We demonstrate near-unity, broadband absorbing optoelectronic devices using sub-15 nm thick transition metal dichalcogenides (TMDCs) of molybdenum and tungsten as van der Waals semiconductor active layers. Specifically, we report that near-unity light absorption is possible in extremely thin (<15 nm) van der Waals semiconductor structures by coupling to strongly damped optical modes of semiconductor/metal heterostructures. We further fabricate Schottky junction devices using these highly absorbing heterostructures and characterize their optoelectronic performance. Our work addresses one of the key criteria to enable TMDCs as potential candidates to achieve high optoelectronic efficiency.", "date": "2016-09-14", "date_type": "published", "publication": "Nano Letters", "volume": "16", "number": "9", "publisher": "American Chemical Society", "pagerange": "5482-5487", "id_number": "CaltechAUTHORS:20160907-121115025", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160907-121115025", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.6b01914", "primary_object": { "basename": "1605.04057.pdf", "url": "https://authors.library.caltech.edu/records/f4pka-t5f58/files/1605.04057.pdf" }, "related_objects": [ { "basename": "nl6b01914_si_001.pdf", "url": "https://authors.library.caltech.edu/records/f4pka-t5f58/files/nl6b01914_si_001.pdf" } ], "pub_year": "2016", "author_list": "Jariwala, Deep; Davoyan, Artur R.; et al." }, { "id": "https://authors.library.caltech.edu/records/pnjan-4gc12", "eprint_id": 71966, "eprint_status": "archive", "datestamp": "2023-08-20 13:37:38", "lastmod": "2023-10-23 17:43:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Jintai", "name": { "family": "Lin", "given": "Jintai" } }, { "id": "Tong-Dan", "name": { "family": "Tong", "given": "Dan" } }, { "id": "Davis-S", "name": { "family": "Davis", "given": "Steven" } }, { "id": "Ni-Ruijing", "name": { "family": "Ni", "given": "Ruijing" } }, { "id": "Tan-Xiaoxiao", "name": { "family": "Tan", "given": "Xiaoxiao" } }, { "id": "Pan-Da", "name": { "family": "Pan", "given": "Da" } }, { "id": "Zhao-Hongyan", "name": { "family": "Zhao", "given": "Hongyan" } }, { "id": "Lu-Zifeng", "name": { "family": "Lu", "given": "Zifeng" } }, { "id": "Streets-D-G", "name": { "family": "Streets", "given": "David" } }, { "id": "Feng-Tong", "name": { "family": "Feng", "given": "Tong" } }, { "id": "Zhang-Qiang", "name": { "family": "Zhang", "given": "Qiang" }, "orcid": "0000-0002-8376-131X" }, { "id": "Yan-Yingying", "name": { "family": "Yan", "given": "Yingying" } }, { "id": "Hu-Yongyun", "name": { "family": "Hu", "given": "Yongyun" } }, { "id": "Li-Jing", "name": { "family": "Li", "given": "Jing" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Jiang-Xujia", "name": { "family": "Jiang", "given": "Xujia" } }, { "id": "Geng-Guannan", "name": { "family": "Geng", "given": "Guannan" } }, { "id": "He-Kebin", "name": { "family": "He", "given": "Kebin" } }, { "id": "Huang-Yi", "name": { "family": "Huang", "given": "Yi" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } } ] }, "title": "Global climate forcing of aerosols embodied in international trade", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Macmillan Publishers Limited, part of Springer Nature. \n\nReceived 22 May 2016; Accepted 22 July 2016; Published online 05 September 2016. \n\nThis research is supported by the National Natural Science Foundation of China (NSFC; 41422502 and 41222036), the 973 program (2014CB441303 and 2014CB441301), and World Wide Fund for Nature (WWF; 10010002399). Z.Lu and D.S. acknowledge the support of the Modeling, Analysis and Predictability (MAP) programme of the National Aeronautics and Space Administration (NASA) under Proposal No. 08-MAP-0143. Z.Liu acknowledges the support of NSFC (41501605). D.G. acknowledges the support of NSFC (41328008), the National Key R&D Program of China (2016YFA0602604), the UK Economic and Social Research Council (ES/L016028/1), and the Natural Environment Research Council (NE/N00714X/1). \n\nAuthor Contributions: J.L., Q.Z. and Y.Huang conceived the research. D.T., D.P., H.Z., T.F., Z.L., D.S. and Q.Z. calculated the emissions. R.N., Y.Y. and J.L. conducted chemical transport model simulations. X.T., R.N., Y.Huang and J.L. conducted radiative transfer model simulations. J.L., S.D., Y.Huang and R.N. led the analysis and writing. All authors contributed to the writing. \n\nThese authors contributed equally to this work :Jintai Lin & Dan Tong.\n\nThe authors declare no competing financial interests.\n\n

Supplemental Material - ngeo2798-s1.pdf

", "abstract": "International trade separates regions consuming goods and services from regions where goods and related aerosol pollution are produced. Yet the role of trade in aerosol climate forcing attributed to different regions has never been quantified. Here, we contrast the direct radiative forcing of aerosols related to regions' consumption of goods and services against the forcing due to emissions produced in each region. Aerosols assessed include black carbon, primary organic aerosol, and secondary inorganic aerosols, including sulfate, nitrate and ammonium. We find that global aerosol radiative forcing due to emissions produced in East Asia is much stronger than the forcing related to goods and services ultimately consumed in that region because of its large net export of emissions-intensive goods. The opposite is true for net importers such as Western Europe and North America: global radiative forcing related to consumption is much greater than the forcing due to emissions produced in these regions. Overall, trade is associated with a shift of radiative forcing from net importing to net exporting regions. Compared to greenhouse gases such as carbon dioxide, the short atmospheric lifetimes of aerosols cause large localized differences between consumption- and production-related radiative forcing. International efforts to reduce emissions in the exporting countries will help alleviate trade-related climate and health impacts of aerosols while lowering global emissions.", "date": "2016-09", "date_type": "published", "publication": "Nature Geoscience", "volume": "9", "number": "10", "publisher": "Nature Publishing Group", "pagerange": "790-794", "id_number": "CaltechAUTHORS:20161111-153840554", "issn": "1752-0894", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161111-153840554", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41422502" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41222036" }, { "agency": "National Natural Science Foundation of China", "grant_number": "2014CB441303" }, { "agency": "National Natural Science Foundation of China", "grant_number": "2014CB441301" }, { "agency": "World Wide Fund for Nature (WWF)", "grant_number": "10010002399" }, { "agency": "NASA", "grant_number": "08-MAP-0143" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41501605" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41328008" }, { "agency": "National Natural Science Foundation of China", "grant_number": "2016YFA0602604" }, { "agency": "Economic and Social Research Council", "grant_number": "ES/L016028/1" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/N00714X/1" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/NGEO2798", "primary_object": { "basename": "ngeo2798-s1.pdf", "url": "https://authors.library.caltech.edu/records/pnjan-4gc12/files/ngeo2798-s1.pdf" }, "pub_year": "2016", "author_list": "Lin, Jintai; Tong, Dan; et al." }, { "id": "https://authors.library.caltech.edu/records/yhkqb-y4081", "eprint_id": 70413, "eprint_status": "archive", "datestamp": "2023-08-20 13:31:24", "lastmod": "2023-10-20 22:56:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Liu-Wen-Bo", "name": { "family": "Liu", "given": "Wen-Bo" }, "orcid": "0000-0003-2687-557X" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Potassium tert-Butoxide-Catalyzed Dehydrogenative Cross-Coupling of Heteroarenes with Hydrosilanes", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 Organic Syntheses, Inc. \n\nPublished on the web 08/26/2016. \n\nThis publication is based on work supported by the NSF under the CCI Center for Selective C-H Functionalization (CHE-1205646) and under CHE-1212767. W.-B.L. wishes to thank the Shanghai Institute of Organic Chemistry (SIOC) and Prof. S.-L. You for a postdoctoral fellowship. A.A.T. is grateful to the Resnick Sustainability Institute at Caltech and to Dow Chemical for a predoctoral fellowship, and to NSERC for a PGS D fellowship. We also thank Dr. Scott Virgil and the Caltech Center for Catalysis and Chemical Synthesis for access to analytical equipment. \n\nA.A.T. and W.-B.L. contributed equally to this work.", "abstract": "A. 1-Methyl-2-(triethylsilyl)-1H-indole (2). An oven-dried 100-mL round-bottom Schlenk flask is equipped with a Teflon-coated magnetic stir bar (25 x 8 mm) and capped with a rubber septum (Note 1). The side arm of the flask is connected to Schlenk line and the flask is cooled to room temperature under vacuum and back-filled with nitrogen. Potassium tert-butoxide (1.34 g, 12.0 mmol, 0.2 equiv) is added to the flask under positive nitrogen flow (Notes 2 and 3), and then the flask is evacuated and back-filled with nitrogen three times. N-Methylindole (7.48 mL, 7.86 g, 60.0 mmol, 1.0 equiv) and triethylsilane (28.6 mL, 20.82 g, 179.5 mmol, 3.0 equiv) are added sequentially via syringe through the septum, resulting in a yellow heterogeneous mixture (Figure 1). After the septum is replaced with a glass stopper (Note 4), the reaction mixture is degassed (Note 5) and stirred at 45 \u00baC for 76 h (Note 6), resulting in a dark purple solution. The heating bath is removed and the reaction mixture is allowed to cool to ambient temperature (~25 \u00baC), then anhydrous diethyl ether (30 mL) is added slowly while stirring (Note 7).", "date": "2016-08-26", "date_type": "published", "publication": "Organic Syntheses", "volume": "93", "publisher": "Organic Syntheses, Inc.", "pagerange": "263-271", "id_number": "CaltechAUTHORS:20160919-073857486", "issn": "0078-6209", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160919-073857486", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "Shanghai Institute of Organic Chemistry (SIOC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.15227/orgsyn.093.0263", "pub_year": "2016", "author_list": "Toutov, Anton A.; Liu, Wen-Bo; et al." }, { "id": "https://authors.library.caltech.edu/records/1d8b1-mjy92", "eprint_id": 67884, "eprint_status": "archive", "datestamp": "2023-08-20 13:04:04", "lastmod": "2025-04-23 15:32:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-Ana-M", "name": { "family": "Brown", "given": "Ana M." } }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Ab initio phonon coupling and optical response of hot electrons in plasmonic metals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Physical Society.\n\nReceived 1 February 2016; revised manuscript received 26 July 2016; published 11 August 2016.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. P.N. and W.A.G. acknowledge financial support from NG NEXT for this project. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.B. is supported by a National Science Foundation Graduate Research Fellowship, a Link Foundation Energy Fellowship, and the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (Grant No. DE-SC0001293).\n\n

Published - PhysRevB.94.075120.pdf

Submitted - 1602.00625v1.pdf

Supplemental Material - Ag_ImEpsilon.dat

Supplemental Material - Ag_ReEpsilon.dat

Supplemental Material - Al_ImEpsilon.dat

Supplemental Material - Al_ReEpsilon.dat

Supplemental Material - Au_ImEpsilon.dat

Supplemental Material - Au_ReEpsilon.dat

Supplemental Material - Cu_ImEpsilon.dat

Supplemental Material - Cu_ReEpsilon.dat

Supplemental Material - SI.pdf

", "abstract": "Ultrafast laser measurements probe the nonequilibrium dynamics of excited electrons in metals with increasing temporal resolution. Electronic structure calculations can provide a detailed microscopic understanding of hot electron dynamics, but a parameter-free description of pump-probe measurements has not yet been possible, despite intensive research, because of the phenomenological treatment of electron-phonon interactions. We present ab initio predictions of the electron-temperature dependent heat capacities and electron-phonon coupling coefficients of plasmonic metals. We find substantial differences from free-electron and semiempirical estimates, especially in noble metals above transient electron temperatures of 2000 K, because of the previously neglected strong dependence of electron-phonon matrix elements on electron energy. We also present first-principles calculations of the electron-temperature dependent dielectric response of hot electrons in plasmonic metals, including direct interband and phonon-assisted intraband transitions, facilitating complete theoretical predictions of the time-resolved optical probe signatures in ultrafast laser experiments.", "date": "2016-08", "date_type": "published", "publication": "Physical Review B", "volume": "94", "number": "7", "publisher": "American Physical Society", "pagerange": "Art. No. 075120", "id_number": "CaltechAUTHORS:20160613-140325024", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160613-140325024", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Link Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "other_numbering_system": { "items": [ { "id": "1175", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.94.075120", "primary_object": { "basename": "Al_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Al_ReEpsilon.dat" }, "related_objects": [ { "basename": "Au_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Au_ImEpsilon.dat" }, { "basename": "Cu_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Cu_ReEpsilon.dat" }, { "basename": "Ag_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Ag_ImEpsilon.dat" }, { "basename": "Al_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Al_ImEpsilon.dat" }, { "basename": "Au_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Au_ReEpsilon.dat" }, { "basename": "Cu_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Cu_ImEpsilon.dat" }, { "basename": "PhysRevB.94.075120.pdf", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/PhysRevB.94.075120.pdf" }, { "basename": "SI.pdf", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/SI.pdf" }, { "basename": "1602.00625v1.pdf", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/1602.00625v1.pdf" }, { "basename": "Ag_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Ag_ReEpsilon.dat" } ], "pub_year": "2016", "author_list": "Brown, Ana M.; Sundararaman, Ravishankar; et al." }, { "id": "https://authors.library.caltech.edu/records/ajy3c-5gr09", "eprint_id": 70075, "eprint_status": "archive", "datestamp": "2023-08-20 12:58:04", "lastmod": "2023-10-20 21:23:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pesko-D-M", "name": { "family": "Pesko", "given": "Danielle M." }, "orcid": "0000-0002-4833-0119" }, { "id": "Webb-M-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Jung-Yukyung", "name": { "family": "Jung", "given": "Yukyung" } }, { "id": "Zheng-Qi", "name": { "family": "Zheng", "given": "Qi" } }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Coates-G-W", "name": { "family": "Coates", "given": "Geoffrey W." }, "orcid": "0000-0002-3400-2552" }, { "id": "Balsara-N-P", "name": { "family": "Balsara", "given": "Nitash P." }, "orcid": "0000-0002-0106-5565" } ] }, "title": "Universal Relationship between Conductivity and Solvation-Site Connectivity in Ether-Based Polymer Electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: April 23, 2016; Revised: July 4, 2016; Published: July 15, 2016. \n\nThe authors gratefully acknowledge Zhen-Gang Wang for useful discussions. This research was supported by the National Science Foundation under DMREF Award NSF-CHE-1335486. DSC experiments were performed at the Molecular Foundry user facilities at Lawrence Berkeley National Laboratory supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract DE-AC02-05CH11231. M.A.W. also acknowledges support from the Resnick Sustainability Institute. \n\nD.M.P., M.A.W., and Y.J. contributed equally to the work. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ma6b00851_si_001.pdf

", "abstract": "We perform a joint experimental and computational study of ion transport properties in a systematic set of linear polyethers synthesized via acyclic diene metathesis (ADMET) polymerization. We measure ionic conductivity, \u03c3, and glass transition temperature, T_g, in mixtures of polymer and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt. While T_g is known to be an important factor in the ionic conductivity of polymer electrolytes, recent work indicates that the number and proximity of lithium ion solvation sites in the polymer also play an important role, but this effect has yet to be systematically investigated. Here, adding aliphatic linkers to a poly(ethylene oxide) (PEO) backbone lowers T_g and dilutes the polar groups; both factors influence ionic conductivity. To isolate these effects, we introduce a two-step normalization scheme. In the first step, Vogel\u2013Tammann\u2013Fulcher (VTF) fits are used to calculate a temperature-dependent reduced conductivity, \u03c3_r(T), which is defined as the conductivity of the electrolyte at a fixed value of T \u2013 T_g. In the second step, we compute a nondimensional parameter f_(exp), defined as the ratio of the reduced molar conductivity of the electrolyte of interest to that of a reference polymer (PEO) at a fixed salt concentration. We find that f_(exp) depends only on oxygen mole fraction, x_0, and is to a good approximation independent of temperature and salt concentration. Molecular dynamics simulations are performed on neat polymers to quantify the occurrences of motifs that are similar to those obtained in the vicinity of isolated lithium ions. We show that f_(exp) is a linear function of the simulation-derived metric of connectivity between solvation sites. From the relationship between \u03c3_r and f_(exp) we derive a universal equation that can be used to predict the conductivity of ether-based polymer electrolytes at any salt concentration and temperature.", "date": "2016-07-26", "date_type": "published", "publication": "Macromolecules", "volume": "49", "number": "14", "publisher": "American Chemical Society", "pagerange": "5244-5255", "id_number": "CaltechAUTHORS:20160831-130326773", "issn": "0024-9297", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160831-130326773", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1335486" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.macromol.6b00851", "primary_object": { "basename": "ma6b00851_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ajy3c-5gr09/files/ma6b00851_si_001.pdf" }, "pub_year": "2016", "author_list": "Pesko, Danielle M.; Webb, Michael A.; et al." }, { "id": "https://authors.library.caltech.edu/records/vx6tx-dsv97", "eprint_id": 67844, "eprint_status": "archive", "datestamp": "2023-08-20 12:45:22", "lastmod": "2025-04-23 15:32:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "McFarland-E-W", "name": { "family": "McFarland", "given": "Eric W." } } ] }, "title": "A comparative technoeconomic analysis of renewable hydrogen production using solar energy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Royal Society of Chemistry. \n\nReceived 19 Aug 2015, Accepted 05 May 2016, First published online 26 May 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Support for this technoeconomic analysis was provided jointly by the Dow Centre for Sustainable Engineering Innovation at the University of Queensland, and the Resnick Institute for Sustainability at Caltech.\n\n

Published - c5ee02573g.pdf

Supplemental Material - c5ee02573g1.pdf

", "abstract": "A technoeconomic analysis of photoelectrochemical (PEC) and photovoltaic-electrolytic (PV-E) solar-hydrogen production of 10 000 kg H_2 day^(\u22121) (3.65 kilotons per year) was performed to assess the economics of each technology, and to provide a basis for comparison between these technologies as well as within the broader energy landscape. Two PEC systems, differentiated primarily by the extent of solar concentration (unconcentrated and 10\u00d7 concentrated) and two PV-E systems, differentiated by the degree of grid connectivity (unconnected and grid supplemented), were analyzed. In each case, a base-case system that used established designs and materials was compared to prospective systems that might be envisioned and developed in the future with the goal of achieving substantially lower overall system costs. With identical overall plant efficiencies of 9.8%, the unconcentrated PEC and non-grid connected PV-E system base-case capital expenses for the rated capacity of 3.65 kilotons H_2 per year were $205 MM ($293 per m^2 of solar collection area (m_S^(\u22122)), $14.7 W_(H2,P)^(\u22121)) and $260 MM ($371 m_S^(\u22122), $18.8 W_(H2,P)^(\u22121)), respectively. The untaxed, plant-gate levelized costs for the hydrogen product (LCH) were $11.4 kg^(\u22121) and $12.1 kg^(\u22121) for the base-case PEC and PV-E systems, respectively. The 10\u00d7 concentrated PEC base-case system capital cost was $160 MM ($428 m_S^(\u22122), $11.5 W_(H2,P)^(\u22121)) and for an efficiency of 20% the LCH was $9.2 kg^(\u22121). Likewise, the grid supplemented base-case PV-E system capital cost was $66 MM ($441 m_S^(\u22122), $11.5 W_(H2,P)^(\u22121)), and with solar-to-hydrogen and grid electrolysis system efficiencies of 9.8% and 61%, respectively, the LCH was $6.1 kg^(\u22121). As a benchmark, a proton-exchange membrane (PEM) based grid-connected electrolysis system was analyzed. Assuming a system efficiency of 61% and a grid electricity cost of $0.07 kWh^(\u22121), the LCH was $5.5 kg^(\u22121). A sensitivity analysis indicated that, relative to the base-case, increases in the system efficiency could effect the greatest cost reductions for all systems, due to the areal dependencies of many of the components. The balance-of-systems (BoS) costs were the largest factor in differentiating the PEC and PV-E systems. No single or combination of technical advancements based on currently demonstrated technology can provide sufficient cost reductions to allow solar hydrogen to directly compete on a levelized cost basis with hydrogen produced from fossil energy. Specifically, a cost of CO_2 greater than \u223c$800 (ton CO_2)^(\u22121) was estimated to be necessary for base-case PEC hydrogen to reach price parity with hydrogen derived from steam reforming of methane priced at $12 GJ^(\u22121) ($1.39 (kg H_2)^(\u22121)). A comparison with low CO_2 and CO_2-neutral energy sources indicated that base-case PEC hydrogen is not currently cost-competitive with electrolysis using electricity supplied by nuclear power or from fossil-fuels in conjunction with carbon capture and storage. Solar electricity production and storage using either batteries or PEC hydrogen technologies are currently an order of magnitude greater in cost than electricity prices with no clear advantage to either battery or hydrogen storage as of yet. Significant advances in PEC technology performance and system cost reductions are necessary to enable cost-effective PEC-derived solar hydrogen for use in scalable grid-storage applications as well as for use as a chemical feedstock precursor to CO_2-neutral high energy-density transportation fuels. Hence such applications are an opportunity for foundational research to contribute to the development of disruptive approaches to solar fuels generation systems that can offer higher performance at much lower cost than is provided by current embodiments of solar fuels generators. Efforts to directly reduce CO_2 photoelectrochemically or electrochemically could potentially produce products with higher value than hydrogen, but many, as yet unmet, challenges include catalytic efficiency and selectivity, and CO_2 mass transport rates and feedstock cost. Major breakthroughs are required to obtain viable economic costs for solar hydrogen production, but the barriers to achieve cost-competitiveness with existing large-scale thermochemical processes for CO_2 reduction are even greater.", "date": "2016-07-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "7", "publisher": "Royal Society of Chemistry", "pagerange": "2354-2371", "id_number": "CaltechAUTHORS:20160610-132918453", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160610-132918453", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of Queensland" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c5ee02573g", "primary_object": { "basename": "c5ee02573g1.pdf", "url": "https://authors.library.caltech.edu/records/vx6tx-dsv97/files/c5ee02573g1.pdf" }, "related_objects": [ { "basename": "c5ee02573g.pdf", "url": "https://authors.library.caltech.edu/records/vx6tx-dsv97/files/c5ee02573g.pdf" } ], "pub_year": "2016", "author_list": "Shaner, Matthew R.; Atwater, Harry A.; et al." }, { "id": "https://authors.library.caltech.edu/records/bmggy-apx67", "eprint_id": 62917, "eprint_status": "archive", "datestamp": "2023-08-22 18:10:29", "lastmod": "2023-10-25 21:59:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." }, "orcid": "0000-0001-8849-4516" }, { "id": "Brinkmann-Chen-Sabine", "name": { "family": "Brinkmann-Chen", "given": "Sabine" }, "orcid": "0000-0002-5419-4192" }, { "id": "Buller-Andrew-R", "name": { "family": "Buller", "given": "Andrew R." }, "orcid": "0000-0002-9635-4844" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Artificial domain duplication replicates evolutionary history of ketol-acid reductoisomerases", "ispublished": "pub", "full_text_status": "public", "keywords": "ketol-acid reductoisomerase; domain duplication; fold evolution; knotted proteins", "note": "\u00a9 2015 John Wiley & Sons, Inc. \n\nManuscript Received: 19 October 2015. Manuscript Accepted: 1 December 2015. Accepted manuscript online: 8 December 2015. Version of record online: 21 December 2015. Issue online: 23 June 2016. \n\nWe thank Dr. Jens Kaiser and Pavle Nikolovski for their continued support. The Molecular Observatory is supported by the Gordon and Betty Moore Foundation, the Beckman Institute, and the Sanofi-Aventis Bioengineering Research Program at Caltech. \n\nResearch Funding: Gordon and Betty Moore Foundation - Grant Number: GBMF2809; Resnick Sustainability Institute at Caltech; Ruth Kirschstein NIH Postdoctoral Fellowship - Grant Number: F32GM110851.\n\n

Supplemental Material - pro2852-sup-0001-suppinfo01.pdf

", "abstract": "The duplication of protein structural domains has been proposed as a common mechanism for the generation of new protein folds. A particularly interesting case is the class II ketol-acid reductoisomerase (KARI), which putatively arose from an ancestral class I KARI by duplication of the C-terminal domain and corresponding loss of obligate dimerization. As a result, the class II enzymes acquired a deeply embedded figure-of-eight knot. To test this evolutionary hypothesis we constructed a novel class II KARI by duplicating the C-terminal domain of a hyperthermostable class I KARI. The new protein is monomeric, as confirmed by gel filtration and x-ray crystallography, and has the deeply-knotted class II KARI fold. Surprisingly, its catalytic activity is nearly unchanged from the parent KARI. This provides strong evidence in support of domain duplication as the mechanism for the evolution of the class II KARI fold and demonstrates the ability of domain duplication to generate topological novelty in a function-neutral manner.", "date": "2016-07", "date_type": "published", "publication": "Protein Science", "volume": "25", "number": "7", "publisher": "Wiley", "pagerange": "1241-1248", "id_number": "CaltechAUTHORS:20151215-081458127", "issn": "0961-8368", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151215-081458127", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2809" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH Postdoctoral Fellowship", "grant_number": "F32GM110851" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Sanofi-Aventis Bioengineering Research Program" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/pro.2852", "pmcid": "PMC4918412", "primary_object": { "basename": "pro2852-sup-0001-suppinfo01.pdf", "url": "https://authors.library.caltech.edu/records/bmggy-apx67/files/pro2852-sup-0001-suppinfo01.pdf" }, "pub_year": "2016", "author_list": "Cahn, Jackson K. B.; Brinkmann-Chen, Sabine; et al." }, { "id": "https://authors.library.caltech.edu/records/s5m42-60r25", "eprint_id": 69315, "eprint_status": "archive", "datestamp": "2023-08-20 12:35:00", "lastmod": "2023-10-20 16:47:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Duvvuri-S", "name": { "family": "Duvvuri", "given": "Subrahmanyam" }, "orcid": "0000-0001-8082-1658" }, { "id": "McKeon-B-J", "name": { "family": "McKeon", "given": "Beverley" }, "orcid": "0000-0003-4220-1583" } ] }, "title": "Nonlinear interactions isolated through scale synthesis in experimental wall turbulence", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Physical Society. \n\n(Received 8 April 2016; published 15 July 2016) \n\nWe gratefully acknowledge AFOSR (Grant No. FA 9550-12-1-0469, program manager D. Smith) for financial support of this work and a graduate fellowship (S.D.) from the Resnick Institute at Caltech. We also thank K. Rosenberg and D. Huynh for their help with the wind tunnel experimental setup.\n\n

Published - PhysRevFluids.1.032401.pdf

", "abstract": "An experimental investigation of nonlinear scale interactions in a forced turbulent boundary layer is presented here. A dynamic wall perturbation mechanism was used to externally force two distinct large-scale synthetic modes with well-defined spatial and temporal wave numbers in a fully turbulent flow. The focus is on characterizing the nonlinear flow response at triadically consistent wave numbers that arises from the direct interactions of the two synthetic modes. These experimental results isolate triadic scale interactions in wall turbulence in a unique fashion, and provide the ability to explore the dynamics of scale coupling in a systematic and detailed manner. The ideas advanced here are intended to contribute towards modeling efforts of high-Reynolds-number wall turbulence.", "date": "2016-07", "date_type": "published", "publication": "Physical Review Fluids", "volume": "1", "number": "3", "publisher": "American Physical Society", "pagerange": "Art. No. 032401(R)", "id_number": "CaltechAUTHORS:20160729-122826684", "issn": "2469-990X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160729-122826684", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA 9550-12-1-0469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1103/PhysRevFluids.1.032401", "primary_object": { "basename": "PhysRevFluids.1.032401.pdf", "url": "https://authors.library.caltech.edu/records/s5m42-60r25/files/PhysRevFluids.1.032401.pdf" }, "pub_year": "2016", "author_list": "Duvvuri, Subrahmanyam and McKeon, Beverley" }, { "id": "https://authors.library.caltech.edu/records/r91nx-8he66", "eprint_id": 69159, "eprint_status": "archive", "datestamp": "2023-08-20 12:29:27", "lastmod": "2025-04-25 23:04:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Reilly-M-E", "name": { "family": "O'Reilly", "given": "Matthew E." } }, { "id": "Johnson-S-I", "name": { "family": "Johnson", "given": "Samantha I." } }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Gunnoe-T-B", "name": { "family": "Gunnoe", "given": "T. Brent" }, "orcid": "0000-0001-5714-3887" } ] }, "title": "Transition-Metal-Mediated Nucleophilic Aromatic Substitution with Acids", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: April 8, 2016; Published: June 9, 2016. \n\nThe authors acknowledge support from the Center for Catalytic Hydrocarbon Functionalization, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award Number DE-SC0001298 for initial catalyst preparation and the National Science Foundation (CHE-1465145, DMR-1436985, and CBET 1512759) for support of mechanistic studies. S.I.J. was generously supported by the Resnick Sustainability Institute. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - om6b00285_si_001.pdf

Supplemental Material - om6b00285_si_002.xyz

", "abstract": "Transition-metal-mediated nucleophilic aromatic substitution (S_NAr) reactions prefer that a suitably strong nucleophile be in an aprotic medium. Usually, using protic nucleophile/medium requires high reaction temperatures (>180 \u00b0C) to overcome the attenuated nucleophilicity for attack on the arene \u03c0 system. Surprisingly, we demonstrate herein a Rh^(III)-mediated S_NAr reaction of a fluoroarene moiety with RCO_2H (R = CH_3, CF_3) in acid media that proceeds at moderate temperatures (<100 \u00b0C). We show both by experimental and with DFT calculations that the mechanism proceeds through an internal nucleophilic aromatic substitution (I-S_NAr), where the nucleophile coordinates to the metal ion prior to substitution, thereby mitigating the acid influence.", "date": "2016-06-27", "date_type": "published", "publication": "Organometallics", "volume": "35", "number": "12", "publisher": "American Chemical Society", "pagerange": "2053-2056", "id_number": "CaltechAUTHORS:20160722-083932887", "issn": "0276-7333", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160722-083932887", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001298" }, { "agency": "NSF", "grant_number": "CHE-1465145" }, { "agency": "NSF", "grant_number": "DMR-1436985" }, { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.organomet.6b00285", "primary_object": { "basename": "om6b00285_si_001.pdf", "url": "https://authors.library.caltech.edu/records/r91nx-8he66/files/om6b00285_si_001.pdf" }, "related_objects": [ { "basename": "om6b00285_si_002.xyz", "url": "https://authors.library.caltech.edu/records/r91nx-8he66/files/om6b00285_si_002.xyz" } ], "pub_year": "2016", "author_list": "O'Reilly, Matthew E.; Johnson, Samantha I.; et al." }, { "id": "https://authors.library.caltech.edu/records/151ed-5fd34", "eprint_id": 67333, "eprint_status": "archive", "datestamp": "2023-09-22 22:53:36", "lastmod": "2025-04-26 02:42:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Aguirre-Quintana-Luis-M", "name": { "family": "Aguirre Quintana", "given": "Luis M." }, "orcid": "0000-0003-0736-415X" }, { "id": "Johnson-Samantha-I.", "name": { "family": "Johnson", "given": "Samantha I." }, "orcid": "0000-0001-6495-9892" }, { "id": "Corona-Sydney-L", "name": { "family": "Corona", "given": "Sydney L." }, "orcid": "0000-0002-4962-619X" }, { "id": "Villatoro-Walther", "name": { "family": "Villatoro", "given": "Walther" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Takase-Michael-K", "name": { "family": "Takase", "given": "Michael K." }, "orcid": "0000-0001-8365-3645" }, { "id": "VanderVelde-D-G", "name": { "family": "VanderVelde", "given": "David G." }, "orcid": "0000-0002-2907-0366" }, { "id": "Winkler-Jay-R", "name": { "family": "Winkler", "given": "Jay R." }, "orcid": "0000-0002-4453-9716" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Blakemore-James-D", "name": { "family": "Blakemore", "given": "James D." }, "orcid": "0000-0003-4172-7460" } ] }, "title": "Proton\u2013hydride tautomerism in hydrogen evolution catalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 National Academy of Sciences. \n\nContributed by Harry B. Gray, April 17, 2016 (sent for review February 4, 2016; reviewed by Alexander Miller and David Milstein). Published online before print May 24, 2016. \n\nS.I.J. thanks Dr. Robert Nielsen for helpful discussions. This research, which was carried out in part at the Molecular Materials Research Center and the Laser Resource Center of the Beckman Institute (California Institute of Technology), was supported by NSF CCI Solar Fuels Program CHE-1305124. S.I.J. and J.D.B. acknowledge fellowships from the Resnick Sustainability Institute at Caltech. \n\nAuthor contributions: S.I.J., D.G.V., J.R.W., H.B.G., and J.D.B. designed research; L.M.A.Q., S.I.J., S.L.C., W.V., M.K.T., and J.D.B. performed research; W.A.G. contributed new reagents/analytic tools; L.M.A.Q., S.I.J., S.L.C., W.V., M.K.T., D.G.V., J.R.W., H.B.G., and J.D.B. analyzed data; and S.I.J., J.R.W., H.B.G., and J.D.B. wrote the paper. \n\nReviewers: A.M., University of North Carolina; and D.M., The Weizmann Institute of Science. \n\nThe authors declare no conflict of interest. \n\nData deposition: The atomic coordinates and structure factors have been deposited in the Cambridge Crystallographic Data Centre (accession no. 1424707). \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1606018113/-/DCSupplemental.\n\n

Published - 6409.full.pdf

Supplemental Material - pnas.1606018113.sapp.pdf

", "abstract": "Efficient generation of hydrogen from renewable resources requires development of catalysts that avoid deep wells and high barriers. Information about the energy landscape for H_2 production can be obtained by chemical characterization of catalytic intermediates, but few have been observed to date. We have isolated and characterized a key intermediate in 2e^\u2013 + 2H^+ \u2192 H_2 catalysis. This intermediate, obtained by treatment of Cp*Rh(bpy) (Cp*, \u03b7^5-pentamethylcyclopentadienyl; bpy, \u03ba^2-2,2\u2032-bipyridyl) with acid, is not a hydride species but rather, bears [\u03b7^4-Cp*H] as a ligand. Delivery of a second proton to this species leads to evolution of H_2 and reformation of \u03b7^5-Cp* bound to rhodium(III). With suitable choices of acids and bases, the Cp*Rh(bpy) complex catalyzes facile and reversible interconversion of H^+ and H_2.", "date": "2016-06-07", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "113", "number": "23", "publisher": "National Academy of Sciences", "pagerange": "6409-6414", "id_number": "CaltechAUTHORS:20160525-080847791", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160525-080847791", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" } ] }, "doi": "10.1073/pnas.1606018113", "pmcid": "PMC4988566", "primary_object": { "basename": "6409.full.pdf", "url": "https://authors.library.caltech.edu/records/151ed-5fd34/files/6409.full.pdf" }, "related_objects": [ { "basename": "pnas.1606018113.sapp.pdf", "url": "https://authors.library.caltech.edu/records/151ed-5fd34/files/pnas.1606018113.sapp.pdf" } ], "pub_year": "2016", "author_list": "Aguirre Quintana, Luis M.; Johnson, Samantha I.; et al." }, { "id": "https://authors.library.caltech.edu/records/w90d3-03159", "eprint_id": 68685, "eprint_status": "archive", "datestamp": "2023-08-20 11:50:39", "lastmod": "2025-04-23 15:29:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Plasmonic hot carrier dynamics in solid-state and chemical systems for energy conversion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Prineha Narang et al., published by De Gruyter Open.\nThis work is licensed under the Creative Commons Attribution-Non Commercial-No Derivs 3.0 License.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. P. N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute.\n\n

Published - nanoph-2016-0007.pdf

", "abstract": "Surface plasmons provide a pathway to efficiently absorb and confine light in metallic nanostructures, thereby bridging photonics to the nano scale. The decay of surface plasmons generates energetic 'hot' carriers, which can drive chemical reactions or be injected into semiconductors for nano-scale photochemical or photovoltaic energy conversion. Novel plasmonic hot carrier devices and architectures continue to be demonstrated, but the complexity of the underlying processes make a complete microscopic understanding of all the mechanisms and design considerations for such devices extremely challenging.Here,we review the theoretical and computational efforts to understand and model plasmonic hot carrier devices.We split the problem into three steps: hot carrier generation, transport and collection, and review theoretical approaches with the appropriate level of detail for each step along with their predictions. We identify the key advances necessary to complete the microscopic mechanistic picture and facilitate the design of the next generation of devices and materials for plasmonic energy conversion.", "date": "2016-06", "date_type": "published", "publication": "Nanophotonics", "volume": "5", "number": "1", "publisher": "De Gruyter", "pagerange": "96-111", "id_number": "CaltechAUTHORS:20160627-104035060", "issn": "2192-8606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160627-104035060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1515/nanoph-2016-0007", "primary_object": { "basename": "nanoph-2016-0007.pdf", "url": "https://authors.library.caltech.edu/records/w90d3-03159/files/nanoph-2016-0007.pdf" }, "pub_year": "2016", "author_list": "Narang, Prineha; Sundararaman, Ravishankar; et al." }, { "id": "https://authors.library.caltech.edu/records/xt843-srs47", "eprint_id": 66525, "eprint_status": "archive", "datestamp": "2023-08-20 11:38:24", "lastmod": "2023-10-18 18:10:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Two-Dimensional Halide Perovskites: Tuning Electronic Activities of Defects", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: March 5, 2016. Revised: April 13, 2016. Publication Date (Web): April 21, 2016. \n\nY.L. thanks discussions with Professor Wan-Jian Yin and acknowledges the support from Resnick Prize Postdoctoral Fellowship at Caltech. H.X. and W.A.G. were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. DOE under Award No. DE-SC0004993. This research was also supported by NSF (CBET-1512759, program manager: Robert McCabe), DOE (DE FOA 0001276, program manager: James Davenport). This work used computational resources of National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract DE-AC02-05CH11231, and the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by NSF Grant ACI-1053575. \n\nThe authors declare no competing financial interest.\n\n

Published - acs_2Enanolett_2E6b00964.pdf

Submitted - 1605.02422.pdf

Supplemental Material - nl6b00964_si_001.pdf

", "abstract": "Two-dimensional (2D) halide perovskites are emerging as promising candidates for nanoelectronics and optoelectronics. To realize their full potential, it is important to understand the role of those defects that can strongly impact material properties. In contrast to other popular 2D semiconductors (e.g., transition metal dichalcogenides MX_2) for which defects typically induce harmful traps, we show that the electronic activities of defects in 2D perovskites are significantly tunable. For example, even with a fixed lattice orientation one can change the synthesis conditions to convert a line defect (edge or grain boundary) from electron acceptor to inactive site without deep gap states. We show that this difference originates from the enhanced ionic bonding in these perovskites compared with MX_2. The donors tend to have high formation energies and the harmful defects are difficult to form at a low halide chemical potential. Thus, we unveil unique properties of defects in 2D perovskites and suggest practical routes to improve them.", "date": "2016-05-11", "date_type": "published", "publication": "Nano Letters", "volume": "16", "number": "5", "publisher": "American Chemical Society", "pagerange": "3335-3340", "id_number": "CaltechAUTHORS:20160428-094924238", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160428-094924238", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CBET-151275" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FOA-0001276" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acs.nanolett.6b00964", "primary_object": { "basename": "1605.02422.pdf", "url": "https://authors.library.caltech.edu/records/xt843-srs47/files/1605.02422.pdf" }, "related_objects": [ { "basename": "acs_2Enanolett_2E6b00964.pdf", "url": "https://authors.library.caltech.edu/records/xt843-srs47/files/acs_2Enanolett_2E6b00964.pdf" }, { "basename": "nl6b00964_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xt843-srs47/files/nl6b00964_si_001.pdf" } ], "pub_year": "2016", "author_list": "Liu, Yuanyue; Xiao, Hai; et al." }, { "id": "https://authors.library.caltech.edu/records/6hgjq-xax90", "eprint_id": 66485, "eprint_status": "archive", "datestamp": "2023-08-20 11:37:06", "lastmod": "2023-10-18 18:08:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Darnton-T-V", "name": { "family": "Darnton", "given": "Tania V." } }, { "id": "Hunter-B-M", "name": { "family": "Hunter", "given": "Bryan M." }, "orcid": "0000-0001-8559-9304" }, { "id": "Hill-M-G", "name": { "family": "Hill", "given": "Michael G." } }, { "id": "Z\u00e1li\u0161-S", "name": { "family": "Z\u00e1li\u0161", "given": "Stanislav" } }, { "id": "Vl\u010dek-A-Jr", "name": { "family": "Vl\u010dek", "given": "Anton\u00edn, Jr." } }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Reduced and Superreduced Diplatinum Complexes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: March 9, 2016. Publication Date (Web): April 11, 2016. \n\nWe thank James Blakemore, Angelo Di Bilio, Yan-Choi Lam, and Jay R. Winkler for assistance with experiments and helpful discussions. This work was supported by the NSF CCI Solar Fuels Program (CHE-1305124). Additional support was provided by the Arnold and Mabel Beckman Foundation, the Ministry of Education of the Czech Republic (grants LH13015 and LD14129), and COST Actions CM1202 and CM1405. B.M.H. is a Fellow of the Resnick Sustainability Institute at Caltech; T.V.D. is an NSF Graduate Research Fellow. \n\nAuthor Contributions: T.V.D. and B.M.H. contributed equally. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja6b02559_si_001.pdf

", "abstract": "A d^8\u2013d^8 complex [Pt_2(\u03bc-P_2O_5(BF_2)_4]^(4\u2013) (abbreviated Pt(pop-BF_2)^(4\u2013)) undergoes two 1e\u2013 reductions at E_(1/2) = \u22121.68 and E_p = \u22122.46 V (vs Fc+/Fc) producing reduced Pt(pop-BF_2)^(5\u2013) and superreduced Pt(pop-BF_2)^(6\u2013) species, respectively. The EPR spectrum of Pt(pop-BF_2)^(5\u2013) and UV\u2013vis spectra of both the reduced and the superreduced complexes, together with TD-DFT calculations, reveal successive filling of the 6p\u03c3 orbital accompanied by gradual strengthening of Pt\u2013Pt bonding interactions and, because of 6p\u03c3 delocalization, of Pt\u2013P bonds in the course of the two reductions. Mayer\u2013Millikan Pt\u2013Pt bond orders of 0.173, 0.268, and 0.340 were calculated for the parent, reduced, and superreduced complexes, respectively. The second (5\u2013/6\u2212) reduction is accompanied by a structural distortion that is experimentally manifested by electrochemical irreversibility. Both reduction steps proceed without changing either d^8 Pt electronic configuration, making the superreduced Pt(pop-BF_2)^(6\u2013) a very rare 6p^2 \u03c3-bonded binuclear complex. However, the Pt\u2013Pt \u03c3 bonding interaction is limited by the relatively long bridging-ligand-imposed Pt\u2013Pt distance accompanied by repulsive electronic congestion. Pt(pop-BF_2)^(4\u2013) is predicted to be a very strong photooxidant (potentials of +1.57 and +0.86 V are estimated for the singlet and triplet d\u03c3*p\u03c3 excited states, respectively).", "date": "2016-05-04", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "17", "publisher": "American Chemical Society", "pagerange": "5699-5705", "id_number": "CaltechAUTHORS:20160426-131418190", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160426-131418190", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Ministry of Education of the Czech Republic", "grant_number": "LH13015" }, { "agency": "Ministry of Education of the Czech Republic", "grant_number": "LD14129" }, { "agency": "European Research Council (ERC)", "grant_number": "CM1202" }, { "agency": "European Research Council (ERC)", "grant_number": "CM1405" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.6b02559", "primary_object": { "basename": "ja6b02559_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6hgjq-xax90/files/ja6b02559_si_001.pdf" }, "pub_year": "2016", "author_list": "Darnton, Tania V.; Hunter, Bryan M.; et al." }, { "id": "https://authors.library.caltech.edu/records/fc1t4-vyp84", "eprint_id": 65876, "eprint_status": "archive", "datestamp": "2023-08-20 11:25:18", "lastmod": "2023-10-18 16:53:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hunter-B-M", "name": { "family": "Hunter", "given": "B. M." }, "orcid": "0000-0001-8559-9304" }, { "id": "Hieringer-W", "name": { "family": "Hieringer", "given": "W." } }, { "id": "Winkler-J-R", "name": { "family": "Winkler", "given": "J. R." }, "orcid": "0000-0002-4453-9716" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "H. B." }, "orcid": "0000-0002-7937-7876" }, { "id": "M\u00fcller-A-M", "name": { "family": "M\u00fcller", "given": "A. M." }, "orcid": "0000-0002-2785-6808" } ] }, "title": "Effect of interlayer anions on [NiFe]-LDH nanosheet water oxidation activity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Royal Society of Chemistry. \n\nReceived 5th February 2016, Accepted 17th March 2016. First published online 17 Mar 2016. \n\nWe thank George Rossman for help with solid-state IR spectroscopy. Research was carried out in the Laser Resource Center and the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. This work was supported by the NSF CCI Solar Fuels Program (CHE-1305124) and the Arnold and Mabel Beckman Foundation. B. M. H. is a Fellow of the Resnick Sustainability Institute at Caltech. W. H. thanks the Deutsche Forschungsgemeinschaft and the Cluster of Excellence \"Engineering of Advanced Materials\" at the University of Erlangen-N\u00fcrnberg for support.\n\n

Published - c6ee00377j.pdf

Supplemental Material - c6ee00377j1.pdf

", "abstract": "We synthesized nickel\u2013iron layered double hydroxide ([NiFe]-LDH) nanosheets with different interlayer anions to probe their role in water oxidation catalysis. In alkaline electrolyte in ambient air, carbonate rapidly replaced other interlayer anions and catalytic activity was highest. Electrocatalytic water oxidation in virtually carbonate-free alkaline electrolyte revealed that activity was a function of anion basicity. Our [NiFe]-LDH nanosheets, prepared by pulsed laser ablation in liquids, were regenerated in carbonate-containing aqueous KOH. Anion binding motifs were assessed by X-ray photoelectron spectroscopy in combination with density functional theory calculations, suggesting that nitrite species bound to edge-site Fe in the precatalyst correlated with higher water oxidation activity.", "date": "2016-05", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "2016", "number": "5", "publisher": "Royal Society of Chemistry", "pagerange": "1734-1743", "id_number": "CaltechAUTHORS:20160404-081907582", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160404-081907582", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" }, { "agency": "University of Erlangen-N\u00fcrnberg" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/C6EE00377J", "primary_object": { "basename": "c6ee00377j1.pdf", "url": "https://authors.library.caltech.edu/records/fc1t4-vyp84/files/c6ee00377j1.pdf" }, "related_objects": [ { "basename": "c6ee00377j.pdf", "url": "https://authors.library.caltech.edu/records/fc1t4-vyp84/files/c6ee00377j.pdf" } ], "pub_year": "2016", "author_list": "Hunter, B. M.; Hieringer, W.; et al." }, { "id": "https://authors.library.caltech.edu/records/ax90z-5vc18", "eprint_id": 65625, "eprint_status": "archive", "datestamp": "2023-08-20 11:25:10", "lastmod": "2023-10-18 16:11:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dodani-Sheel-C", "name": { "family": "Dodani", "given": "Sheel C." }, "orcid": "0000-0003-0271-6080" }, { "id": "Kiss-Gert", "name": { "family": "Kiss", "given": "Gert" } }, { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." }, "orcid": "0000-0001-8849-4516" }, { "id": "Su-Ye", "name": { "family": "Su", "given": "Ye" } }, { "id": "Pande-Vijay-S", "name": { "family": "Pande", "given": "Vijay S." }, "orcid": "0000-0003-2774-1178" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Discovery of a regioselectivity switch in nitrating P450s guided by molecular dynamics simulations and Markov models", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Macmillan Publishers Limited. \n\nReceived 15 September 2015; Accepted 03 February 2016; Published online 21 March 2016. \n\nWe thank J. Kaiser and P. Nikolovski of the Beckman Molecular Observatory (Caltech) for assistance with crystallography and S. Virgil and the 3CS Center for Catalysis and Chemical Synthesis (Caltech) for assistance with LC-MS analyses. This work was funded by the Gordon and Betty Moore Foundation through grant GBMF2809 to the Caltech Programmable Molecular Technology Initiative (to F.H.A.). S.C.D. is supported by a Ruth L. Kirschstein National Research Service Award postdoctoral fellowship from the National Institutes of Health (NIH) (5F32GM106618). G.K. acknowledges support from the Lawrence Scholars Program, the NIH Simbios Program (U54 GM072970) and the Center for Molecular Analysis and Design (Stanford). J.K.B.C. acknowledges the support of the Resnick Sustainability Institute (Caltech). The Beckman Molecular Observatory is supported by the Gordon and Betty Moore Foundation, the Beckman Institute and the Sanofi-Aventis Bioengineering Research Program (Caltech). The authors thank S. Brinkmann-Chen, T. K. Hyster, J. A. McIntosh, C. K. Prier, R. T. McGibbon and M. M. Sultan for helpful discussions. This research is part of the Blue Waters sustained-petascale computing project, which is supported by the National Science Foundation (awards OCI-0725070 and ACI-1238993) and the state of Illinois. The content of this paper is solely the responsibility of the authors and does not represent the official views of any of the funding agencies. \n\nAuthor contributions: S.C.D. and G.K. contributed equally to this work. S.C.D. and G.K. designed the research. S.C.D., G.K., J.K.B.C. and Y.S. performed the research. F.H.A. and V.S.P. supervised and provided advice. S.C.D., G.K. and J.K.B.C. analysed the data. S.C.D., G.K., J.K.B.C. and F.H.A. wrote the text and conceived the figures with input from all of the authors. \n\nCompeting financial interests: The authors declare no competing financial interests.\n\n

Accepted Version - nihms-757651.pdf

Supplemental Material - nchem.2474-s1.pdf

Supplemental Material - nchem.2474-s2.zip

", "abstract": "The dynamic motions of protein structural elements, particularly flexible loops, are intimately linked with diverse aspects of enzyme catalysis. Engineering of these loop regions can alter protein stability, substrate binding and even dramatically impact enzyme function. When these flexible regions are unresolvable structurally, computational reconstruction in combination with large-scale molecular dynamics simulations can be used to guide the engineering strategy. Here we present a collaborative approach that consists of both experiment and computation and led to the discovery of a single mutation in the F/G loop of the nitrating cytochrome P450 TxtE that simultaneously controls loop dynamics and completely shifts the enzyme's regioselectivity from the C4 to the C5 position of L-tryptophan. Furthermore, we find that this loop mutation is naturally present in a subset of homologous nitrating P450s and confirm that these uncharacterized enzymes exclusively produce 5-nitro-L-tryptophan, a previously unknown biosynthetic intermediate.", "date": "2016-05", "date_type": "published", "publication": "Nature Chemistry", "volume": "8", "number": "5", "publisher": "Nature Publishing Group", "pagerange": "419-425", "id_number": "CaltechAUTHORS:20160323-124510465", "issn": "1755-4330", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160323-124510465", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2809" }, { "agency": "NIH Postdoctoral Fellowship", "grant_number": "5F32GM106618" }, { "agency": "Lawrence Scholars Program" }, { "agency": "NIH", "grant_number": "U54 GM072970" }, { "agency": "Stanford University" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Caltech Sanofi-Aventis Bioengineering Research Program" }, { "agency": "NSF", "grant_number": "OCI-0725070" }, { "agency": "NSF", "grant_number": "ACI-1238993" }, { "agency": "State of Illinois" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/NCHEM.2474", "pmcid": "PMC4843824", "primary_object": { "basename": "nchem.2474-s1.pdf", "url": "https://authors.library.caltech.edu/records/ax90z-5vc18/files/nchem.2474-s1.pdf" }, "related_objects": [ { "basename": "nchem.2474-s2.zip", "url": "https://authors.library.caltech.edu/records/ax90z-5vc18/files/nchem.2474-s2.zip" }, { "basename": "nihms-757651.pdf", "url": "https://authors.library.caltech.edu/records/ax90z-5vc18/files/nihms-757651.pdf" } ], "pub_year": "2016", "author_list": "Dodani, Sheel C.; Kiss, Gert; et al." }, { "id": "https://authors.library.caltech.edu/records/6h3c7-yk451", "eprint_id": 66239, "eprint_status": "archive", "datestamp": "2023-08-20 11:20:35", "lastmod": "2023-10-18 17:17:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lionetti-D", "name": { "family": "Lionetti", "given": "Davide" }, "orcid": "0000-0002-4937-886X" }, { "id": "De-Ruiter-G", "name": { "family": "De Ruiter", "given": "Graham" } }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "A trans-Hyponitrite Intermediate in the Reductive Coupling and Deoxygenation of Nitric Oxide by a Tricopper\u2013Lewis Acid Complex", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: January 29, 2016; Publication Date (Web): March 30, 2016. \n\nThis work was supported by Caltech and the PRF (T.A.). T.A. is grateful for Sloan, Dreyfus, and Cottrell fellowships. We thank Dr. Michael K. Takase and Lawrence M. Henling for assistance with X-ray crystallography. We thank Professor Jonas C. Peters for use of two infrared spectrometers. D.L. gratefully acknowledges a graduate fellowship from the Resnick Sustainability Institute at Caltech. The Bruker KAPPA APEXII X-ray diffractometer was purchased via an NSF Chemistry Research Instrumentation award to Caltech (CHE-0639094). \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ja6b01083_si_001.cif

Supplemental Material - ja6b01083_si_002.cif

Supplemental Material - ja6b01083_si_003.pdf

", "abstract": "The reduction of nitric oxide (NO) to nitrous oxide (N_2O) is a process relevant to biological chemistry as well as to the abatement of certain environmental pollutants. One of the proposed key intermediates in NO reduction is hyponitrite (N_2O_2^(2\u2013)), the product of reductive coupling of two NO molecules. We report the reductive coupling of NO by an yttrium\u2013tricopper complex generating a trans-hyponitrite moiety supported by two \u03bc-O-bimetallic (Y,Cu) cores, a previously unreported coordination mode. Reaction of the hyponitrite species with Br\u00f8nsted acids leads to the generation of N_2O, demonstrating the viability of the hyponitrite complex as an intermediate in NO reduction to N_2O. The additional reducing equivalents stored in each tricopper unit are employed in a subsequent step for N_2O reduction to N_2, for an overall (partial) conversion of NO to N_2. The combination of Lewis acid and multiple redox active metals facilitates this four electron conversion via an isolable hyponitrite intermediate.", "date": "2016-04-20", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "15", "publisher": "American Chemical Society", "pagerange": "5008-5011", "id_number": "CaltechAUTHORS:20160418-101830823", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160418-101830823", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "American Chemical Society Petroleum Research Fund" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Cottrell Scholar of Research Corporation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-0639094" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.6b01083", "primary_object": { "basename": "ja6b01083_si_002.cif", "url": "https://authors.library.caltech.edu/records/6h3c7-yk451/files/ja6b01083_si_002.cif" }, "related_objects": [ { "basename": "ja6b01083_si_003.pdf", "url": "https://authors.library.caltech.edu/records/6h3c7-yk451/files/ja6b01083_si_003.pdf" }, { "basename": "ja6b01083_si_001.cif", "url": "https://authors.library.caltech.edu/records/6h3c7-yk451/files/ja6b01083_si_001.cif" } ], "pub_year": "2016", "author_list": "Lionetti, Davide; De Ruiter, Graham; et al." }, { "id": "https://authors.library.caltech.edu/records/n60s4-w3b53", "eprint_id": 65618, "eprint_status": "archive", "datestamp": "2023-08-22 17:45:24", "lastmod": "2025-04-26 03:02:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Merinov-Boris-V", "name": { "family": "Merinov", "given": "Boris V." }, "orcid": "0000-0002-2783-4262" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Origin of low sodium capacity in graphite and generally weak substrate binding of Na and Mg among alkali and alkaline earth metals", "ispublished": "pub", "full_text_status": "public", "keywords": "energy storage; Na-ion battery; Mg-ion battery; quantum-mechanical calculations", "note": "\u00a9 2016 National Academy of Sciences. \n\nContributed by William A. Goddard III, February 19, 2016 (sent for review January 25, 2016; reviewed by Yi Cui and Michael L. Klein). Published online before print March 21, 2016. \n\nY.L. thanks Drs. Brandon Wood, Suhuai Wei, and Jiayu Wan for helpful discussions and Brandon Wood for providing access to the Lawrence Livermore National Laboratory computational resources, which were used for some of the computations (supported under the Laboratory Directed Research and Development Program). Most of the calculations were performed on National Energy Research Scientific Computing Center, a Department of Energy (DOE) Office of Science User Facility supported by the Office of Science of the US DOE under Contract DE-AC02-05CH11231. Y.L. acknowledges the support from Resnick Prize Postdoctoral Fellowship at Caltech. This research was funded by the Bosch Energy Research Network and by NSF (CBET 1512759). \n\nReviewers: Y.C., Stanford University; and M.L.K., Temple University. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1602473113/-/DCSupplemental.\n\n

Published - PNAS-2016-Liu-3735-9.pdf

Submitted - 1604.03602.pdf

Supplemental Material - pnas.201602473SI.pdf

", "abstract": "It is well known that graphite has a low capacity for Na but a high capacity for other alkali metals. The growing interest in alternative cation batteries beyond Li makes it particularly important to elucidate the origin of this behavior, which is not well understood. In examining this question, we find a quite general phenomenon: among the alkali and alkaline earth metals, Na and Mg generally have the weakest chemical binding to a given substrate, compared with the other elements in the same column of the periodic table. We demonstrate this with quantum mechanics calculations for a wide range of substrate materials (not limited to C) covering a variety of structures and chemical compositions. The phenomenon arises from the competition between trends in the ionization energy and the ion\u2013substrate coupling, down the columns of the periodic table. Consequently, the cathodic voltage for Na and Mg is expected to be lower than those for other metals in the same column. This generality provides a basis for analyzing the binding of alkali and alkaline earth metal atoms over a broad range of systems.", "date": "2016-04-05", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "113", "number": "14", "publisher": "National Academy of Sciences", "pagerange": "3735-3739", "id_number": "CaltechAUTHORS:20160323-103905765", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160323-103905765", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "Bosch Energy Research Network" } ] }, "other_numbering_system": { "items": [ { "id": "1158", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.1602473113", "pmcid": "PMC4833228", "primary_object": { "basename": "1604.03602.pdf", "url": "https://authors.library.caltech.edu/records/n60s4-w3b53/files/1604.03602.pdf" }, "related_objects": [ { "basename": "pnas.201602473SI.pdf", "url": "https://authors.library.caltech.edu/records/n60s4-w3b53/files/pnas.201602473SI.pdf" }, { "basename": "PNAS-2016-Liu-3735-9.pdf", "url": "https://authors.library.caltech.edu/records/n60s4-w3b53/files/PNAS-2016-Liu-3735-9.pdf" } ], "pub_year": "2016", "author_list": "Liu, Yuanyue; Merinov, Boris V.; et al." }, { "id": "https://authors.library.caltech.edu/records/59g54-8es80", "eprint_id": 65407, "eprint_status": "archive", "datestamp": "2023-08-20 11:13:07", "lastmod": "2023-10-18 15:59:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Prier-Christopher-K", "name": { "family": "Prier", "given": "Christopher K." }, "orcid": "0000-0003-0902-1636" }, { "id": "Hyster-Todd-K", "name": { "family": "Hyster", "given": "Todd K." }, "orcid": "0000-0003-3560-355X" }, { "id": "Farwell-Christopher-C", "name": { "family": "Farwell", "given": "Christopher C." } }, { "id": "Huang-Audrey-N", "name": { "family": "Huang", "given": "Audrey" } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Asymmetric Enzymatic Synthesis of Allylic Amines: A Sigmatropic Rearrangement Strategy", "ispublished": "pub", "full_text_status": "public", "keywords": "amination \u00b7 biocatalysis \u00b7 cytochrome P450 \u00b7 directed evolution \u00b7 nitrene transfer", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. \n\nReceived: February 1, 2016. First published: 11 March 2016. \n\nOur research is supported by the National Science Foundation, Division of Molecular and Cellular Biosciences (grant MCB-1513007). C.K.P. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. T.H.K. and C.C.F. were supported by a Ruth L. Kirschstein National Research Service Award (F32GM108143) and an NSF Graduate Research Fellowship, respectively. We thank Dr. Scott Virgil and the Center for Catalysis and Chemical Synthesis at Caltech for assistance with chiral chromatography.\n\n

Accepted Version - nihms763326.pdf

Supplemental Material - anie201601056-sup-0001-misc_information.pdf

", "abstract": "Sigmatropic rearrangements, while rare in biology, offer opportunities for the efficient and selective synthesis of complex chemical motifs. A \"P411\" serine-ligated variant of cytochrome P450_(BM3) has been engineered to initiate a sulfimidation/[2,3]-sigmatropic rearrangement sequence in whole E. coli cells, a non-natural function for any enzyme, providing access to enantioenriched, protected allylic amines. Five mutations in the enzyme substantially enhance its activity toward this new function, demonstrating the evolvability of the catalyst toward challenging nitrene transfer reactions. The evolved catalyst additionally performs the highly enantioselective imidation of non-allylic sulfides.", "date": "2016-04-04", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "55", "number": "15", "publisher": "Wiley", "pagerange": "4711-4715", "id_number": "CaltechAUTHORS:20160317-072334231", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160317-072334231", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "MCB-1513007" }, { "agency": "Ruth L. Kirschstein National Research Service Awards", "grant_number": "F32GM108143" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201601056", "pmcid": "PMC4818679", "primary_object": { "basename": "anie201601056-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/59g54-8es80/files/anie201601056-sup-0001-misc_information.pdf" }, "related_objects": [ { "basename": "nihms763326.pdf", "url": "https://authors.library.caltech.edu/records/59g54-8es80/files/nihms763326.pdf" } ], "pub_year": "2016", "author_list": "Prier, Christopher K.; Hyster, Todd K.; et al." }, { "id": "https://authors.library.caltech.edu/records/jfha5-syj78", "eprint_id": 66312, "eprint_status": "archive", "datestamp": "2023-08-20 11:00:48", "lastmod": "2023-10-18 17:57:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Del-Castillo-Trevor-J", "name": { "family": "Del Castillo", "given": "Trevor J." } }, { "id": "Thompson-Niklas-B", "name": { "family": "Thompson", "given": "Niklas B." }, "orcid": "0000-0003-2745-4945" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "A Synthetic Single-Site Fe Nitrogenase: High Turnover, Freeze-Quench \u2075\u2077Fe M\u00f6ssbauer Data, and a Hydride Resting State", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: February 16, 2016; Publication Date (Web): March 29, 2016. \n\nThis work was supported by the NIH (GM 070757) and the Gordon and Betty Moore Foundation. T.J.D.C. acknowledges the support of the NSF for a Graduate Fellowship (GRFP), and N.B.T. acknowledges the support of the Resnick Sustainability Institute at Caltech for a Graduate Fellowship. \n\nT.J.D.C. and N.B.T. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms824014.pdf

Supplemental Material - ja6b01706_si_001.pdf

", "abstract": "The mechanisms of the few known molecular nitrogen-fixing systems, including nitrogenase enzymes, are of much interest but are not fully understood. We recently reported that Fe\u2013N\u2082 complexes of tetradentate P\u2083\u1d31 ligands (E = B, C) generate catalytic yields of NH\u2083 under an atmosphere of N\u2082 with acid and reductant at low temperatures. Here we show that these Fe catalysts are unexpectedly robust and retain activity after multiple reloadings. Nearly an order of magnitude improvement in yield of NH\u2083 for each Fe catalyst has been realized (up to 64 equiv of NH\u2083 produced per Fe for P\u2083\u1d2e and up to 47 equiv for P\u2083\u1d9c) by increasing acid/reductant loading with highly purified acid. Cyclic voltammetry shows the apparent onset of catalysis at the P\u2083\u1d2eFe\u2013N\u2082/P\u2083\u1d2eFe\u2013N\u2082\u2013 couple and controlled-potential electrolysis of P\u2083\u1d2eFe\u207a at \u221245 \u00b0C demonstrates that electrolytic N\u2082 reduction to NH\u2083 is feasible. Kinetic studies reveal first-order rate dependence on Fe catalyst concentration (P\u2083\u1d2e), consistent with a single-site catalyst model. An isostructural system (PP\u2083^(Si)) is shown to be appreciably more selective for hydrogen evolution. In situ freeze-quench M\u00f6ssbauer spectroscopy during turnover reveals an iron\u2013borohydrido\u2013hydride complex as a likely resting state of the P\u2083\u1d2eFe catalyst system. We postulate that hydrogen-evolving reaction activity may prevent iron hydride formation from poisoning the P\u2083\u1d2eFe system. This idea may be important to consider in the design of synthetic nitrogenases and may also have broader significance given that intermediate metal hydrides and hydrogen evolution may play a key role in biological nitrogen fixation.", "date": "2016-03-29", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "16", "publisher": "American Chemical Society", "pagerange": "5341-5350", "id_number": "CaltechAUTHORS:20160420-105550849", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160420-105550849", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "GM 070757" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.6b01706", "pmcid": "PMC5079282", "primary_object": { "basename": "ja6b01706_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jfha5-syj78/files/ja6b01706_si_001.pdf" }, "related_objects": [ { "basename": "nihms824014.pdf", "url": "https://authors.library.caltech.edu/records/jfha5-syj78/files/nihms824014.pdf" } ], "pub_year": "2016", "author_list": "Del Castillo, Trevor J.; Thompson, Niklas B.; et al." }, { "id": "https://authors.library.caltech.edu/records/t8tf4-c9756", "eprint_id": 67421, "eprint_status": "archive", "datestamp": "2023-08-22 17:36:09", "lastmod": "2023-10-18 21:10:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Ning", "name": { "family": "Zhang", "given": "Ning" } }, { "id": "Wang-Bing", "name": { "family": "Wang", "given": "Bing" } }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" } ] }, "title": "Carbon emissions dynamics, efficiency gains, and technological innovation in China's industrial sectors", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon emissions performance; Global Malmquist\u2013Luenberger index; Non-radial directional distance function; Chinese industrial sectors", "note": "\u00a9 2016 Elsevier Ltd. \n\nReceived 6 July 2015, Revised 3 November 2015, Accepted 8 January 2016, Available online 10 February 2016.", "abstract": "In China, industrial sectors contribute carbon emissions at a larger scale and more rapidly growing pace than other end-use sectors. This paper thus aims to investigate the dynamic carbon emissions performance of China's industrial sectors using Malmquist-type index. Previous studies suffer from two limitations: the challenge of isolating carbon emissions performance from radial efficiency measures and the infeasibility problem in the calculation process. This paper proposes the non-radial global Malmquist carbon emissions performance index (NGMCPI) as a way of handling those two challenges with measuring dynamic changes in carbon emissions performance. The NGMCPI can be decomposed into efficiency change (EC) and technological change (TC) indexes, which represent the low-carbon catch-up and innovation effects, respectively. Based on the proposed indexes, we examine the dynamic changes in carbon emissions performance and its patterns for 38 Chinese industrial sectors over the 1990\u20132012 period. The results show that dynamic carbon emissions performance was mainly driven by the catch-up effect during the 1990s and boosted by innovation from 2000 to 2012. Some policy implications are proposed based on these empirical results.", "date": "2016-03-15", "date_type": "published", "publication": "Energy", "volume": "99", "publisher": "Elsevier", "pagerange": "10-19", "id_number": "CaltechAUTHORS:20160527-084811475", "issn": "0360-5442", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160527-084811475", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.energy.2016.01.012", "pub_year": "2016", "author_list": "Zhang, Ning; Wang, Bing; et al." }, { "id": "https://authors.library.caltech.edu/records/40m5a-v6p52", "eprint_id": 63106, "eprint_status": "archive", "datestamp": "2023-08-22 17:35:30", "lastmod": "2023-10-25 23:31:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" } ] }, "title": "National carbon emissions from the industry process: Production of glass, soda ash, ammonia, calcium carbide and alumina", "ispublished": "pub", "full_text_status": "public", "keywords": "China; CO_2; Industrial process; Climate policy", "note": "\u00a9 2015 The Author. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived 10 February 2015, Revised 2 November 2015, Accepted 4 November 2015, Available online 11 December 2015. \n\nZhu Liu acknowledges the National Natural Science Foundation of China \u2013 NSFC 41501605, the Resnick Prize Postdoctoral Fellowship and support from Resnick Sustainability Institute.\n\n

Published - 1-s2.0-S0306261915014464-main.pdf

", "abstract": "China has become the world's largest carbon emitter. Its total carbon emission output from fossil fuel combustion and cement production was approximately 10 Gt CO_2 in 2013. However, less is known about carbon emissions from the production of industrial materials, such as mineral products (e.g., lime, soda ash, asphalt roofing), chemical products (e.g., ammonia, nitric acid) and metal products (e.g., iron, steel and aluminum). Carbon emissions from the production processes of these industrial products (in addition to cement production) are also less frequently reported by current international carbon emission datasets. Here we estimated the carbon emissions resulting from the manufacturing of 5 major industrial products in China, given China's dominant position in industrial production in the world. Based on an investigation of China's specific production processes, we devised a methodology for calculating emission factors. The results indicate that China's total carbon emission from the production of alumina, plate glass, soda ash, ammonia and calcium carbide was 233 million tons in 2013, equivalent to the total CO_2 emissions of Spain in 2013. The cumulative emissions from the manufacturing of these 5 products during the period 1990\u20132013 was approximately 2.5 Gt CO_2, more than the annual total CO_2 emissions of India. Thus, quantifying the emissions from industrial processes is critical for understanding the global carbon budget and developing a suitable climate policy.", "date": "2016-03-15", "date_type": "published", "publication": "Applied Energy", "volume": "166", "publisher": "Elsevier", "pagerange": "239-244", "id_number": "CaltechAUTHORS:20151221-130933227", "issn": "0306-2619", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151221-130933227", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "NSFC 41501605" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.apenergy.2015.11.005", "primary_object": { "basename": "1-s2.0-S0306261915014464-main.pdf", "url": "https://authors.library.caltech.edu/records/40m5a-v6p52/files/1-s2.0-S0306261915014464-main.pdf" }, "pub_year": "2016", "author_list": "Liu, Zhu" }, { "id": "https://authors.library.caltech.edu/records/4jd58-64z38", "eprint_id": 64740, "eprint_status": "archive", "datestamp": "2023-08-22 17:33:26", "lastmod": "2023-10-17 21:50:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Torelli-D-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Crompton-J-C", "name": { "family": "Crompton", "given": "J. Chance" } }, { "id": "Javier-A", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Thompson-J-R", "name": { "family": "Thompson", "given": "Joanthan R." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Nickel\u2212Gallium-Catalyzed Electrochemical Reduction of CO_2 to Highly Reduced Products at Low Overpotentials", "ispublished": "pub", "full_text_status": "public", "keywords": "CO_2 reduction; electrocatalysis; nickel gallium; NiGa; ethane; methane; low overpotential; C_2 production", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: December 17, 2015. Publication Date (Web): February 17, 2016. \n\nThe authors would like to thank Prof. Matthew McDowell for his help with TEM and insightful discussions, Dr. Ivonne Ferrer for her help with GC setup and calibration, and Dr. Kimberly Papadantonakis for help with editing. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. D.A.T. recognizes a Graduate Research Fellowship from the National Science Foundation for support. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. J.C.C. acknowledges support from the Department of Defense through the National Defense Science & Engineering Graduate Fellowship Program. N.S.L. acknowledges support through the Multidisciplinary University Research Initiative (MURI) under AFOSR Award No. FA9550-10-1-0572. \n\nThese authors contributed equally (D.A.T. and S.A.F.). \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cs5b02888_si_001.pdf

", "abstract": "We report the electrocatalytic reduction of CO_2 to the highly reduced C_2 products, ethylene and ethane, as well as to the fully reduced C_1 product, methane, on three different phases of nickel\u2013gallium (NiGa, Ni_3Ga, and Ni_5Ga_3) films prepared by drop-casting. In aqueous bicarbonate electrolytes at neutral pH, the onset potential for methane, ethylene, and ethane production on all three phases was found to be \u22120.48 V versus the reversible hydrogen electrode (RHE), among the lowest onset potentials reported to date for the production of C_2 products from CO_2. Similar product distributions and onset potentials were observed for all three nickel\u2013gallium stoichiometries tested. The onset potential for the reduction of CO_2 to C_2 products at low current densities catalyzed by nickel\u2013gallium was >250 mV more positive than that of polycrystalline copper, and approximately equal to that of single crystals of copper, which have some of the lowest overpotentials to date for the reduction of CO_2 to C_2 products and methane. The nickel\u2013gallium films also reduced CO to ethylene, ethane, and methane, consistent with a CO_2 reduction mechanism that first involves the reduction of CO2 to CO. Isotopic labeling experiments with ^(13)CO_2 confirmed that the detected products were produced exclusively by the reduction of CO_2.", "date": "2016-03-04", "date_type": "published", "publication": "ACS Catalysis", "volume": "6", "number": "3", "publisher": "American Chemical Society", "pagerange": "2100-2104", "id_number": "CaltechAUTHORS:20160224-132719916", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160224-132719916", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-10-1-0572" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.5b02888", "primary_object": { "basename": "cs5b02888_si_001.pdf", "url": "https://authors.library.caltech.edu/records/4jd58-64z38/files/cs5b02888_si_001.pdf" }, "pub_year": "2016", "author_list": "Torelli, Daniel A.; Francis, Sonja A.; et al." }, { "id": "https://authors.library.caltech.edu/records/38eaz-zmz59", "eprint_id": 66017, "eprint_status": "archive", "datestamp": "2023-08-22 17:28:42", "lastmod": "2023-10-18 17:03:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xu-Yunjian", "name": { "family": "Xu", "given": "Yunjian" } }, { "id": "Li-Na", "name": { "family": "Li", "given": "Na" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Demand Response With Capacity Constrained Supply Function Bidding", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Demand response; efficiency loss; game theory; Nash equilibrium; renewable generation", "note": "\u00a9 2015 IEEE. \n\nManuscript received October 07, 2014; revised January 06, 2015; accepted April 01, 2015; date of publication May 01, 2015; date of current version February 17, 2016. \n\nThis work was supported in part by the MIT-SUTD International Design Center (IDC) under Grant IDG21400103, the National Science Foundation NetSE under Grant CNS 0911041, ARPA-E under Grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan, R.O.C , under Grant NSC 101-3113-P-008-001, and the Resnick Institute . Paper no. TPWRS-01373-2014.", "abstract": "We study the problem faced by an operator who aims to allocate a certain amount of load adjustment (either load reduction or increment) to multiple consumers so as to minimize the aggregate consumer disutility. We propose and analyze a simple uniform-price market mechanism where every consumer submits a single bid to choose a supply function from a group of parameterized ones. These parameterized supply functions are designed to ensure that every consumer's load adjustment is within an exogenous capacity limit that is determined by the current power system operating condition. We show that the proposed mechanism yields bounded efficiency loss at a Nash equilibrium. In particular, the proposed mechanism is shown to achieve approximate social optimality at a Nash equilibrium, if the total capacity limit excluding the consumer with the largest one is much larger than the total amount of load to be adjusted. We complement our analysis through numerical case studies.", "date": "2016-03", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "31", "number": "2", "publisher": "IEEE", "pagerange": "1377-1394", "id_number": "CaltechAUTHORS:20160408-101533727", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160408-101533727", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "MIT-SUTD International Design Center (IDC)", "grant_number": "IDG21400103" }, { "agency": "NSF NetSE", "grant_number": "CNS 0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 101-3113-P-008-001" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2015.2421932", "pub_year": "2016", "author_list": "Xu, Yunjian; Li, Na; et al." }, { "id": "https://authors.library.caltech.edu/records/vraa4-fn762", "eprint_id": 64635, "eprint_status": "archive", "datestamp": "2023-08-20 10:18:02", "lastmod": "2023-10-17 21:34:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gupta-Ayush", "name": { "family": "Gupta", "given": "Ayush" } }, { "id": "Blakemore-James-D", "name": { "family": "Blakemore", "given": "James D." }, "orcid": "0000-0003-4172-7460" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Immobilization and electrochemical properties of ruthenium and iridium complexes on carbon electrodes", "ispublished": "pub", "full_text_status": "restricted", "keywords": "surface chemistry, x-ray photoelectron spectroscopy, cyclic voltammetry, solar fuels", "note": "\u00a9 2016 IOP Publishing Ltd. \n\nReceived 10 June 2015, revised 30 July 2015. Accepted for publication 11 August 2015. Published 12 February 2016. \n\nThis research was carried out in part at the Molecular materials Research Center of the Beckman Institute at Caltech. The research was supported by the Resnick Sustainability Institute at Caltech (Postdoctoral Fellowship to J D B) and the NSF CCI Solar Fuels Program (CHE-1305124 and a CCI Postdoctoral Fellowship to J D B). The x-ray photoelectron spectroscopy was supported by a contract with the California Energy Commission (500-11-023).", "abstract": "We report the synthesis and surface immobilization of two new pyrene-appended molecular metal complexes: a ruthenium tris(bipyridyl) complex (1) and a bipyridyl complex of [Cp^*Ir] (2) (Cp^*\u2009\u2009=\u2009\u2009pentamethylcyclopentadienyl). X-ray photoelectron spectroscopy confirmed successful immobilization on high surface area carbon electrodes, with the expected elemental ratios for the desired compounds. Electrochemical data collected in acetonitrile solution revealed a reversible reduction of 1 near\u2009\u2009\u22121.4\u2009V, and reduction of 2 near\u2009\u2009\u22120.75\u2009V. The noncovalent immobilization, driven by association of the appended pyrene groups with the surface, was sufficiently stable to enable studies of the molecular electrochemistry. Electroactive surface coverage of 1 was diminished by only 27% over three hours soaking in electrolyte solution as measured by cyclic voltammetry. The electrochemical response of 2 resembled its soluble analogues, and suggested that ligand exchange occurred on the surface. Together, the results demonstrate that noncovalent immobilization routes are suitable for obtaining fundamental understanding of immobilized metal complexes and their reductive electrochemical properties.", "date": "2016-02-12", "date_type": "published", "publication": "Journal of Physics: Condensed Matter", "volume": "28", "number": "9", "publisher": "IOP", "pagerange": "Art. No. 094002", "id_number": "CaltechAUTHORS:20160222-122103336", "issn": "0953-8984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160222-122103336", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Beckman Institute" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "California Energy Commission", "grant_number": "500-11-023" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" } ] }, "doi": "10.1088/0953-8984/28/9/094002", "pub_year": "2016", "author_list": "Gupta, Ayush; Blakemore, James D.; et al." }, { "id": "https://authors.library.caltech.edu/records/w1r99-4jf37", "eprint_id": 64384, "eprint_status": "archive", "datestamp": "2023-08-20 10:05:58", "lastmod": "2023-10-17 21:09:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Davis-S-J", "name": { "family": "Davis", "given": "Steven J." }, "orcid": "0000-0002-9338-0844" }, { "id": "Feng-Kuishuang", "name": { "family": "Feng", "given": "Kuishuang" }, "orcid": "0000-0001-5139-444X" }, { "id": "Hubacek-K", "name": { "family": "Hubacek", "given": "Klaus" }, "orcid": "0000-0003-2561-6090" }, { "id": "Liang-Sai", "name": { "family": "Liang", "given": "Sai" } }, { "id": "Diaz-Anadon-L", "name": { "family": "Diaz Anadon", "given": "Laura" } }, { "id": "Chen-Bin", "name": { "family": "Chen", "given": "Bin" } }, { "id": "Liu-Jingru", "name": { "family": "Liu", "given": "Jingru" } }, { "id": "Yan-Jinyue", "name": { "family": "Yan", "given": "Jinyue" } }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } } ] }, "title": "Targeted opportunities to address the climate\u2013trade dilemma in China", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Macmillan Publishers Limited. \n\nReceived 12 May 2015; accepted 18 August 2015; published online 28 September 2015. \n\nThis work was supported by China's National Basic Research Program (2014CB441301), the State Key Laboratory of Urban and Regional Ecology, Chinese Academy of Sciences (SKLURE 2015-2-6), and Natural Science Foundation of China project (41328008). Z.L. acknowledges the National Natural Science Foundation of China-NSFC 41501605, the China Sustainable Energy Program of Energy Foundation (G-1407-21749), the Giorgio Ruffolo fellowship and the support from Italy's Ministry for Environment, Land and Sea. S.J.D. acknowledges support from the Institute of Applied Ecology, Chinese Academy of Sciences Fellowships for Young International Distinguished Scientists. S.L. acknowledges the support of the Dow Sustainability Fellows Program. D.G. acknowledges the Economic and Social Research Council funded project 'Dynamics of Green Growth in European and Chinese Cities' (ES/L016028) and his Philip Leverhulme Prize. \n\nContributions: Z.L., K.F. and S.J.D. designed the research. Z.L., K.F. and S.J.D. conceived the paper. K.F. and J.L. provided the data. Z.L., S.J.D., K.F. and K.H. performed the analysis. S.J.D. drew the figures. All authors contributed to writing the paper. \n\nThe authors declare no competing financial interests.\n\n

Supplemental Material - nclimate2800-s1.pdf

", "abstract": "International trade has become the fastest growing driver of global carbon emissions, with large quantities of emissions embodied in exports from emerging economies. International trade with emerging economies poses a dilemma for climate and trade policy: to the extent emerging markets have comparative advantages in manufacturing, such trade is economically efficient and desirable. However, if carbon-intensive manufacturing in emerging countries such as China entails drastically more CO_2 emissions than making the same product elsewhere, then trade increases global CO_2 emissions. Here we show that the emissions embodied in Chinese exports, which are larger than the annual emissions of Japan or Germany, are primarily the result of China's coal-based energy mix and the very high emissions intensity (emission per unit of economic value) in a few provinces and industry sectors. Exports from these provinces and sectors therefore represent targeted opportunities to address the climate\u2013trade dilemma by either improving production technologies and decarbonizing the underlying energy systems or else reducing trade volumes.", "date": "2016-02", "date_type": "published", "publication": "Nature Climate Change", "volume": "6", "number": "2", "publisher": "Nature Publishing Group", "pagerange": "201-206", "id_number": "CaltechAUTHORS:20160210-144704707", "issn": "1758-678X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160210-144704707", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "2014CB441301" }, { "agency": "State Key Laboratory of Urban and Regional Ecology" }, { "agency": "Chinese Academy of Sciences", "grant_number": "SKLURE 2015-2-6" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41328008" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41501605" }, { "agency": "China Sustainable Energy Program", "grant_number": "G-1407-21749" }, { "agency": "Giorgio Ruffolo fellowship" }, { "agency": "Ministero dell'Ambiente e della Tutela del Territorio e del Mare" }, { "agency": "Institute of Applied Ecology" }, { "agency": "Dow Chemical Company" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Economic and Social Research Council", "grant_number": "ES/L016028" }, { "agency": "Leverhulme Trust" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nclimate2800", "primary_object": { "basename": "nclimate2800-s1.pdf", "url": "https://authors.library.caltech.edu/records/w1r99-4jf37/files/nclimate2800-s1.pdf" }, "pub_year": "2016", "author_list": "Liu, Zhu; Davis, Steven J.; et al." }, { "id": "https://authors.library.caltech.edu/records/dt8cw-pj310", "eprint_id": 54044, "eprint_status": "archive", "datestamp": "2023-08-20 10:03:18", "lastmod": "2024-03-05 17:05:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thrampoulidis-C", "name": { "family": "Thrampoulidis", "given": "Christos" }, "orcid": "0000-0001-9053-9365" }, { "id": "Bose-Subhonmesh", "name": { "family": "Bose", "given": "Subhonmesh" }, "orcid": "0000-0002-3445-4479" }, { "id": "Hassibi-B", "name": { "family": "Hassibi", "given": "Babak" }, "orcid": "0000-0002-1375-5838" } ] }, "title": "Optimal Placement of Distributed Energy Storage in Power Networks", "ispublished": "pub", "full_text_status": "public", "keywords": "DC power-flow, energy storage, load-shifting, optimal placement", "note": "\u00a9 2015 IEEE. \n\nManuscript received December 15, 2013; revised August 14, 2014,\nNovember 15, 2014, and April 29, 2015; accepted May 3, 2015. Date of publication May 26, 2015; date of current version January 26, 2016. \n\nThe work of B. Hassibi was supported in part by the National Science Foundation (NSF) under Grants CNS-0932428, CCF-1018927, CCF-1423663, and CCF-1409204, by the Office of Naval Research under the MURI Grant N00014-08-0747, by a Grant from Qualcomm Inc., and by the King Abdulaziz University. This work was also supported in part by the NSF through NetSE CNS 0911041, ARPA-E through GENI DE-AR0000226, Southern California Edison, by the National Science Council of Taiwan through NSC 103-3113-P-008-001, by the Los Alamos National Lab (DoE), Caltech's Resnick Institute, and Andreas Mentzelopoulos Scholarships of the University of Patras. \n\nRecommended by Associate Editor D. Dochain.\n\n

Submitted - Optimal_Placement_of_Distributed_Energy.pdf

", "abstract": "We formulate the optimal placement, sizing and control of storage devices in a power network to minimize generation costs with the intent of load shifting. We assume deterministic demand, a linearized DC approximated power flow model and a fixed available storage budget. Our main result proves that when the generation costs are convex and nondecreasing, there always exists an optimal storage capacity allocation that places zero storage at generation-only buses that connect to the rest of the network via single links. This holds regardless of the demand profiles, generation capacities, line-flow limits and characteristics of the storage technologies. Through a counterexample, we illustrate that this result is not generally true for generation buses with multiple connections. For specific network topologies, we also characterize the dependence of the optimal generation cost on the available storage budget, generation capacities and flow constraints.", "date": "2016-02", "date_type": "published", "publication": "IEEE Transactions on Automatic Control", "volume": "61", "number": "2", "publisher": "IEEE", "pagerange": "416-429", "id_number": "CaltechAUTHORS:20150126-071149016", "issn": "0018-9286", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150126-071149016", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0932428" }, { "agency": "NSF", "grant_number": "CCF-1018927" }, { "agency": "NSF", "grant_number": "CCF-1423663" }, { "agency": "NSF", "grant_number": "CCF-1409204" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-08-1-0747" }, { "agency": "Qualcomm Inc." }, { "agency": "King Abdulaziz University" }, { "agency": "NSF", "grant_number": "CNS-0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Los Alamos National Laboratory" }, { "agency": "Resnick Institute" }, { "agency": "University of Patras" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TAC.2015.2437527", "primary_object": { "basename": "Optimal_Placement_of_Distributed_Energy.pdf", "url": "https://authors.library.caltech.edu/records/dt8cw-pj310/files/Optimal_Placement_of_Distributed_Energy.pdf" }, "pub_year": "2016", "author_list": "Thrampoulidis, Christos; Bose, Subhonmesh; et al." }, { "id": "https://authors.library.caltech.edu/records/yns46-c8p28", "eprint_id": 64284, "eprint_status": "archive", "datestamp": "2023-08-20 09:56:36", "lastmod": "2025-04-25 04:12:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ravichandran-Navaneetha-K", "name": { "family": "Ravichandran", "given": "Navaneetha K." } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Role of thermalizing and nonthermalizing walls in phonon heat conduction along thin films", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Physical Society. \n\nReceived 5 November 2015; revised manuscript received 31 December 2015; published 28 January 2016.\n\nN.K.R. would like to thank the Resnick Sustainability Institute at Caltech and the Dow Chemical Company for fellowship support. A.J.M. was supported by the National Science Foundation under Grant No. CBET CAREER 1254213.\n\n

Published - PhysRevB.93.035314.pdf

Submitted - 1511.03312v1.pdf

Supplemental Material - Supplementary_Material_V1.pdf

", "abstract": "Phonon boundary scattering is typically treated using the Fuchs-Sondheimer theory, which assumes that phonons are thermalized to the local temperature at the boundary. However, whether such a thermalization process actually occurs and its effect on thermal transport remains unclear. Here we examine thermal transport along thin films with both thermalizing and nonthermalizing walls by solving the spectral Boltzmann transport equation for steady state and transient transport. We find that in steady state, the thermal transport is governed by the Fuchs-Sondheimer theory and is insensitive to whether the boundaries are thermalizing or not. In contrast, under transient conditions, the thermal decay rates are significantly different for thermalizing and nonthermalizing walls. We also show that, for transient transport, the thermalizing boundary condition is unphysical due to violation of heat flux conservation at the boundaries. Our results provide insights into the boundary scattering process of thermal phonons over a range of heating length scales that are useful for interpreting thermal measurements on nanostructures.", "date": "2016-01-15", "date_type": "published", "publication": "Physical Review B", "volume": "93", "number": "3", "publisher": "American Physical Society", "pagerange": "Art. No. 035314", "id_number": "CaltechAUTHORS:20160205-142512254", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160205-142512254", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "NSF", "grant_number": "CBET 1254213" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.93.035314", "primary_object": { "basename": "1511.03312v1.pdf", "url": "https://authors.library.caltech.edu/records/yns46-c8p28/files/1511.03312v1.pdf" }, "related_objects": [ { "basename": "PhysRevB.93.035314.pdf", "url": "https://authors.library.caltech.edu/records/yns46-c8p28/files/PhysRevB.93.035314.pdf" }, { "basename": "Supplementary_Material_V1.pdf", "url": "https://authors.library.caltech.edu/records/yns46-c8p28/files/Supplementary_Material_V1.pdf" } ], "pub_year": "2016", "author_list": "Ravichandran, Navaneetha K. and Minnich, Austin J." }, { "id": "https://authors.library.caltech.edu/records/fd3av-nt039", "eprint_id": 61753, "eprint_status": "archive", "datestamp": "2023-08-20 09:40:48", "lastmod": "2023-10-25 15:42:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "J. K. B." }, "orcid": "0000-0001-8849-4516" }, { "id": "Baumschlager-Armin", "name": { "family": "Baumschlager", "given": "A." }, "orcid": "0000-0002-2546-9038" }, { "id": "Brinkmann-Chen-S", "name": { "family": "Brinkmann-Chen", "given": "S." }, "orcid": "0000-0002-5419-4192" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "F. H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Mutations in adenine-binding pockets enhance catalytic properties of NAD(P)H-dependent enzymes", "ispublished": "pub", "full_text_status": "public", "keywords": "directed evolution, enzyme optimality, nicotinamide cofactors, protein engineering, site-saturation mutagenesis", "note": "\u00a9 The Author 2015. Published by Oxford University Press. \n\nReceived September 25, 2015. Accepted September 28, 2015. First published online: October 27, 2015. \n\nThe authors thank Nelson Chou and Drs Sheel Dodani, Tillmann Heinisch and Devin Trudeau for their experimental assistance; Drs Devin Trudeau and John McIntosh for their helpful discussions; and Prof. Dan Tawfik, Prof. Pat Cirino and Prof. Monica Gerth for their helpful comments on this manuscript. They also thank Dr Jens Kaiser and Pavle Nicolovski of the Caltech Molecular Observatory for their continued support. \n\nThis work was supported by the Gordon and Betty Moore Foundation through grant number GBMF2809 to the Caltech Programmable Molecular Technology Initiative and by American Recovery and Reinvestment Act (ARRA) funds through the National Institutes of Health Shared Instrumentation Grant Program, grant number S10RR027203, to F.H.A. J.K.B.C. acknowledges the support of the Resnick Sustainability Institute (Caltech).\n\n

Supplemental Material - gzv057supp.docx

", "abstract": "NAD(P)H-dependent enzymes are ubiquitous in metabolism and cellular processes and are also of great interest for pharmaceutical and industrial applications. Here, we present a structure-guided enzyme engineering strategy for improving catalytic properties of NAD(P)H-dependent enzymes toward native or native-like reactions using mutations to the enzyme's adenine-binding pocket, distal to the site of catalysis. Screening single-site saturation mutagenesis libraries identified mutations that increased catalytic efficiency up to 10-fold in 7 out of 10 enzymes. The enzymes improved in this study represent three different cofactor-binding folds (Rossmann, DHQS-like, and FAD/NAD binding) and utilize both NADH and NADPH. Structural and biochemical analyses show that the improved activities are accompanied by minimal changes in other properties (cooperativity, thermostability, pH optimum, uncoupling), and initial tests on two enzymes (ScADH6 and EcFucO) show improved functionality in Escherichia coli.", "date": "2016-01", "date_type": "published", "publication": "Protein Engineering Design and Selection", "volume": "29", "number": "1", "publisher": "Oxford University Press", "pagerange": "31-38", "id_number": "CaltechAUTHORS:20151030-152836183", "issn": "1741-0126", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151030-152836183", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2809" }, { "agency": "American Recovery and Reinvestment Act (ARRA)" }, { "agency": "NIH", "grant_number": "S10RR027203" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1093/protein/gzv057", "pmcid": "PMC4678007", "primary_object": { "basename": "gzv057supp.docx", "url": "https://authors.library.caltech.edu/records/fd3av-nt039/files/gzv057supp.docx" }, "pub_year": "2016", "author_list": "Cahn, J. K. B.; Baumschlager, A.; et al." }, { "id": "https://authors.library.caltech.edu/records/5xmdh-par02", "eprint_id": 63346, "eprint_status": "archive", "datestamp": "2023-08-20 09:41:27", "lastmod": "2025-04-23 15:30:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-A-M", "name": { "family": "Brown", "given": "Ana M." } }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Nonradiative Plasmon Decay and Hot Carrier Dynamics: Effects of Phonons, Surfaces, and Geometry", "ispublished": "pub", "full_text_status": "restricted", "keywords": "surface plasmons, hot carriers, transport, resistivity, dielectric response, density functional theory", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: October 1, 2015; Accepted: December 10, 2015; Publication Date (Web): December 10, 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science o the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.B. is supported by a National Science Foundation Graduate Research Fellowship, a Link Foundation Energy Fellowship, and the DOE Light\u2212Material Interactions in Energy Conversion Energy Frontier Research Center (DESC0001293). \n\nThe authors declare no competing financial interest.", "abstract": "The behavior of metals across a broad frequency range from microwave to ultraviolet frequencies is of interest in plasmonics, nanophotonics, and metamaterials. Depending on the frequency, losses of collective excitations in metals can be predominantly classical resistive effects or Landau damping. In this context, we present first-principles calculations that capture all of the significant microscopic mechanisms underlying surface plasmon decay and predict the initial excited carrier distributions so generated. Specifically, we include ab initio predictions of phonon-assisted optical excitations in metals, which are critical to bridging the frequency range between resistive losses at low frequencies and direct interband transitions at high frequencies. In the commonly used plasmonic materials, gold, silver, copper, and aluminum, we find that resistive losses compete with phonon-assisted carrier generation below the interband threshold, but hot carrier generation via direct transitions dominates above threshold. Finally, we predict energy-dependent lifetimes and mean free paths of hot carriers, accounting for electron\u2013electron and electron\u2013phonon scattering, to provide insight toward transport of plasmonically generated carriers at the nanoscale.", "date": "2016-01", "date_type": "published", "publication": "ACS Nano", "volume": "10", "number": "1", "publisher": "American Chemical Society", "pagerange": "957-966", "id_number": "CaltechAUTHORS:20160104-150344444", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160104-150344444", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Link Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "other_numbering_system": { "items": [ { "id": "1204", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acsnano.5b06199", "pub_year": "2016", "author_list": "Brown, Ana M.; Sundararaman, Ravishankar; et al." }, { "id": "https://authors.library.caltech.edu/records/k3tyh-n2h33", "eprint_id": 64889, "eprint_status": "archive", "datestamp": "2023-08-20 09:34:25", "lastmod": "2025-04-23 01:11:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "McDowell-M-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Pien-Alex", "name": { "family": "Pien", "given": "Alex" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Si/TiO_2 Tandem-Junction Microwire Arrays for Unassisted Solar-Driven Water Splitting", "ispublished": "pub", "full_text_status": "public", "keywords": "Photoelectrochemistry Silicon Tandem Junction Water splitting", "note": "\u00a9 2016 The Electrochemical Society. \n\nManuscript submitted October 23, 2015; revised manuscript received December 17, 2015. Published January 15, 2016. \n\nThe authors acknowledge Stefan Omelchenko for assistance with the XRD measurements, John Lloyd for discussions about the cTLM measurements and Dr. Shawn Chatman for providing the Xe arc lamp spectral irradiance data. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993. M.R.S.\nacknowledges the Resnick Sustainability Institute for a graduate fellowship.\n\n

Published - J._Electrochem._Soc.-2016-Shaner-H261-4.pdf

Supplemental Material - README.txt

", "abstract": "Tandem-junction microwire array photoelectrodes have been fabricated by coating np^+-Si radial homojunction microwire arrays sequentially with fluorine-doped tin oxide (FTO) and titanium dioxide (TiO_2). These photoelectrodes effected unassisted water splitting under simulated 1 Sun conditions with an open-circuit potential (E_(oc)) of \u22121.5 V vs the formal potential for oxygen evolution, E^(0\u2032)(OH^\u2212/O_2), a current density at E = E^(0\u2032)(OH^\u2212/O_2) of 0.78 mA cm^(\u22122), a fill factor (\u2009ff\u2009) = 0.51, and a photovoltaic-biased photoelectrochemical ideal regenerative cell efficiency of 0.6%.", "date": "2016", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "163", "number": "5", "publisher": "Electrochemical Society", "pagerange": "H261-H264", "id_number": "CaltechAUTHORS:20160301-075443518", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160301-075443518", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1149/2.0141605jes", "primary_object": { "basename": "J._Electrochem._Soc.-2016-Shaner-H261-4.pdf", "url": "https://authors.library.caltech.edu/records/k3tyh-n2h33/files/J._Electrochem._Soc.-2016-Shaner-H261-4.pdf" }, "related_objects": [ { "basename": "README.txt", "url": "https://authors.library.caltech.edu/records/k3tyh-n2h33/files/README.txt" } ], "pub_year": "2016", "author_list": "Shaner, Matthew R.; McDowell, Matthew T.; et al." }, { "id": "https://authors.library.caltech.edu/records/vm1es-78r79", "eprint_id": 61794, "eprint_status": "archive", "datestamp": "2023-08-20 09:13:42", "lastmod": "2023-10-25 15:44:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Liu-Wen-Bo", "name": { "family": "Liu", "given": "Wen-Bo" }, "orcid": "0000-0003-2687-557X" }, { "id": "Betz-K-N", "name": { "family": "Betz", "given": "Kerry N." }, "orcid": "0000-0001-9118-5909" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Catalytic C\u2013H bond silylation of aromatic heterocycles", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 Macmillan Publishers. \n\nPublished online 29 October 2015. \n\nThis work was supported by the US National Science Foundation (NSF) under the Centers for Chemical Innovation (CCI) Center for Selective C\u2013H Functionalization (CCHF) (grant no. CHE-1205646) and under grant no. CHE-1212767. We thank the Novartis Institutes for Biomedical Research Incorporated for the donation of samples to the CCHF. A.A.T. is grateful to the Resnick Sustainability Institute at Caltech and to Dow Chemical for a predoctoral fellowship, and to the National Sciences and Engineering Research Council of Canada (NSERC) for a Postgraduate Scholarship-Doctoral Program (PGS D) fellowship. We thank the Shanghai Institute of Organic Chemistry (SIOC) and S.-L. You (SIOC) for a postdoctoral fellowship to W.-B.L. We thank S. Virgil and the Caltech Center for Catalysis and Chemical Synthesis for access to analytical equipment. \n\nThese authors contributed equally to this work. Anton A Toutov & Wen-Bo Liu. \n\nContributions: A.A.T. and R.H.G. had the idea for and directed the investigations with W.-B.L. and B.M.S. A.A.T., W.-B.L. and K.N.B. developed the reactions, performed the experiments and analyzed the data. A.A.T. and W.-B.L. prepared the manuscript with contributions from all authors. \n\nThe authors declare no competing financial interests.", "abstract": "This protocol describes a method for the direct silylation of the carbon\u2013hydrogen (C\u2013H) bond of aromatic heterocycles using inexpensive and abundant potassium tert-butoxide (KOt-Bu) as the catalyst. This catalytic cross-dehydrogenative coupling of simple hydrosilanes and various electron-rich aromatic heterocycles enables the synthesis of valuable silylated heteroarenes. The products thus obtained can be used as versatile intermediates, which facilitate the divergent synthesis of pharmaceutically relevant compound libraries from a single Si-containing building block. Moreover, a variety of complex Si-containing motifs, such as those produced by this protocol, are being actively investigated as next-generation therapeutic agents, because they can have improved pharmacokinetic properties compared with the original all-carbon drug molecules. Current competing methods for C\u2013H bond silylation tend to be incompatible with functionalities, such as Lewis-basic heterocycles, that are often found in pharmaceutical substances; this leaves de novo synthesis as the principal strategy for preparation of the target sila-drug analog. Moreover, competing methods tend to be limited in the scope of hydrosilane that can be used, which restricts the breadth of silicon-containing small molecules that can be accessed. The approach outlined in this protocol enables the chemoselective and regioselective late-stage silylation of small heterocycles, including drugs and drug derivatives, with a broad array of hydrosilanes in the absence of precious metal catalysts, stoichiometric reagents, sacrificial hydrogen acceptors or high temperatures. Moreover, H_2 is the only by-product generated. The procedure normally requires 48\u201375 h to be completed.", "date": "2015-12", "date_type": "published", "publication": "Nature Protocols", "volume": "10", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "1897-1903", "id_number": "CaltechAUTHORS:20151103-103452993", "issn": "1754-2189", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151103-103452993", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "Dow Chemical Company" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Shanghai Institute of Organic Chemistry (SIOC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nprot.2015.118", "pub_year": "2015", "author_list": "Toutov, Anton A.; Liu, Wen-Bo; et al." }, { "id": "https://authors.library.caltech.edu/records/deecw-wsa54", "eprint_id": 63355, "eprint_status": "archive", "datestamp": "2023-08-20 09:10:35", "lastmod": "2025-04-23 15:30:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cai-Zeng-Hua", "name": { "family": "Cai", "given": "Zeng-Hua" } }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Chen-Shiyou", "name": { "family": "Chen", "given": "Shiyou" } }, { "id": "Duan-Chun-Gang", "name": { "family": "Duan", "given": "Chun-Gang" } }, { "id": "Zhu-Zi-Qiang", "name": { "family": "Zhu", "given": "Zi-Qiang" } }, { "id": "Chu-Jun-Hao", "name": { "family": "Chu", "given": "Jun-Hao" } } ] }, "title": "Cation-Mutation Design of Quaternary Nitride Semiconductors Lattice-Matched to GaN", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: September 9, 2015. Revised: October 31, 2015. Published: November 2, 2015. \n\nWe thank Prof. Jiang Tang for the helpful discussion about the viable synthesis strategy. The work was supported by the National Natural Science Foundation of China (grant no. 91233121, 61125403), Shanghai Rising-Star Program (grant no. 14QA1401500), Special Funds for Major State Basic Research (grant no. 2012CB921401, 2014CB921104), PCSIRT and the computer center of ECNU. P.N. is supported by the National Science Foundation and the Resnick Sustainability Institute at Caltech. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - cm5b03536_si_001.pdf

", "abstract": "The search for new direct bandgap, earth-abundant semiconductors for efficient, high-quality optoelectronic devices, as well as photovoltaic and photocatalytic energy conversion has attracted considerable interest. One methodology for the search is to study ternary and multiternary semiconductors with more elements and more flexible properties. Cation mutation such as binary \u2192 ternary \u2192 quaternary for ZnS \u2192 CuGaS_2 \u2192 Cu_2ZnSnS_4 and ZnO \u2192 LiGaO_2 \u2192 Li_2ZnGeO_4 led to a series of new quaternary chalcogenide and oxide semiconductors with wide applications. Similarly, starting with GaN, ternary nitrides such as ZnSnN_2 and ZnGeN_2 have been designed and synthesized recently. However, quaternary nitride semiconductors have never been reported either theoretically or experimentally. Through a combination of the Materials Genome database with the first-principles calculations, we designed a series of quaternary nitride compounds I\u2013III\u2013Ge_2N_4 (I = Cu, Ag, Li, Na, K; III = Al, Ga, In) following the GaN \u2192 ZnGeN_2 \u2192 I\u2013III\u2013Ge_2N_4 mutation. Akin to Li_2ZnGeO_4, these quaternary nitrides crystallize in a wurtzite-derived structure as their ground state. The thermodynamic stability analysis shows that while most of them are not stable with respect to phase separation, there are two key exceptions (i.e., LiAlGe_2N_4 and LiGaGe_2N_4), which are stable and can be synthesized without any secondary phases. Interestingly, they are both lattice-matched to GaN and ZnO, and their band gaps are direct and larger than that of GaN, 4.36 and 3.74 eV, respectively. They have valence band edges as low as ZnO and conduction band edges as high as GaN, thereby combining the best of GaN and ZnO in a single material. We predict that flexible and efficient band structure engineering can be achieved through forming GaN/LiAlGe_2N_4/LiGaGe_2N_4 heterostructures, which have tremendous potential for ultraviolet optoelectronics.", "date": "2015-11-24", "date_type": "published", "publication": "Chemistry of Materials", "volume": "27", "number": "22", "publisher": "American Chemical Society", "pagerange": "7757-7764", "id_number": "CaltechAUTHORS:20160104-163003841", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160104-163003841", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "91233121" }, { "agency": "National Natural Science Foundation of China", "grant_number": "61125403" }, { "agency": "Shanghai Rising-Star Program", "grant_number": "14QA1401500" }, { "agency": "Special Funds for Major State Basic Research", "grant_number": "2012CB921401" }, { "agency": "Special Funds for Major State Basic Research", "grant_number": "2014CB921104" }, { "agency": "Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT)" }, { "agency": "NSF" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemmater.5b03536", "primary_object": { "basename": "cm5b03536_si_001.pdf", "url": "https://authors.library.caltech.edu/records/deecw-wsa54/files/cm5b03536_si_001.pdf" }, "pub_year": "2015", "author_list": "Cai, Zeng-Hua; Narang, Prineha; et al." }, { "id": "https://authors.library.caltech.edu/records/6qjec-5zx82", "eprint_id": 61871, "eprint_status": "archive", "datestamp": "2023-08-20 09:04:20", "lastmod": "2023-10-25 16:01:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Prier-C-K", "name": { "family": "Prier", "given": "Christopher K." }, "orcid": "0000-0003-0902-1636" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Chemomimetic Biocatalysis: Exploiting the Synthetic Potential of Cofactor-Dependent Enzymes To Create New Catalysts", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: September 3, 2015; Published: October 26, 2015. \n\nOur research is supported by the National Science Foundation, Office of Chemical, Bioengineering, Environmental and Transport Systems SusChEM Initiative (grant CBET-1403077) and by the Division of Molecular and Cellular Biosciences (grant MCB-1513007). C.K.P. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. We thank Drs. Donald Hilvert, Jared Lewis, Gerrit Poelarends, Andrew Buller, Sheel Dodani, Hans Renata, and David Romney for helpful suggestions.\n\n

Published - jacs_2E5b09348.pdf

", "abstract": "Despite the astonishing breadth of enzymes in nature, no enzymes are known for many of the valuable catalytic transformations discovered by chemists. Recent work in enzyme design and evolution, however, gives us good reason to think that this will change. We describe a chemomimetic biocatalysis approach that draws from small-molecule catalysis and synthetic chemistry, enzymology, and molecular evolution to discover or create enzymes with non-natural reactivities. We illustrate how cofactor-dependent enzymes can be exploited to promote reactions first established with related chemical catalysts. The cofactors can be biological, or they can be non-biological to further expand catalytic possibilities. The ability of enzymes to amplify and precisely control the reactivity of their cofactors together with the ability to optimize non-natural reactivity by directed evolution promises to yield exceptional catalysts for challenging transformations that have no biological counterparts.", "date": "2015-11-11", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "137", "number": "44", "publisher": "American Chemical Society", "pagerange": "13992-14006", "id_number": "CaltechAUTHORS:20151105-083025660", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151105-083025660", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CBET-1403077" }, { "agency": "NSF", "grant_number": "MCB-1513007" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jacs.5b09348", "primary_object": { "basename": "jacs_2E5b09348.pdf", "url": "https://authors.library.caltech.edu/records/6qjec-5zx82/files/jacs_2E5b09348.pdf" }, "pub_year": "2015", "author_list": "Prier, Christopher K. and Arnold, Frances H." }, { "id": "https://authors.library.caltech.edu/records/we907-9rp23", "eprint_id": 59958, "eprint_status": "archive", "datestamp": "2023-08-20 08:39:22", "lastmod": "2023-10-23 23:26:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Usiskin-R-E", "name": { "family": "Usiskin", "given": "Robert E." } }, { "id": "Maruyama-Shingo", "name": { "family": "Maruyama", "given": "Shingo" } }, { "id": "Kucharczyk-C-J", "name": { "family": "Kucharczyk", "given": "Chris J." }, "orcid": "0000-0002-4712-839X" }, { "id": "Takeuchi-Ichiro", "name": { "family": "Takeuchi", "given": "Ichiro" } }, { "id": "Haile-S-M", "name": { "family": "Haile", "given": "Sossina M." }, "orcid": "0000-0002-5293-6252" } ] }, "title": "Probing the reaction pathway in (La_(0.8)Sr_(0.2))_(0.95)MnO_(3+\u03b4) using libraries of thin film microelectrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Royal Society of Chemistry 2015. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. \n\nReceived 03 Apr 2015, Accepted 02 Aug 2015, First published online 27 Aug 2015. \n\nThe authors would like to thank McAllister Technical Services for their help in designing and assembling the automated impedance microprobe, and Ben Meyers and Xinqi Chen at University for their assistance in performing the FIB-SEM and SIMS characterization, respectively. This work was funded by the National Science Foundation via awards DMR-0520565 and EFRI-1038307, the Resnick Sustainability Institute at the California Institute of Technology, the National Central University of Taiwan, and the W. M. Keck Foundation. Selected facilities used were supported by the National Science Foundation via Northwestern University's MRSEC, DMR-1121262.\n\n

Published - c5ta02428e.pdf

Supplemental Material - c5ta02428e1.pdf

", "abstract": "Libraries of (La_(0.8)Sr_(0.2))_(0.95)MnO_(3+\u03b4) (LSM) thin film microelectrodes with systematically varied thickness or growth temperature were prepared by pulsed laser deposition, and a novel robotic instrument was used to characterize these libraries in automated fashion by impedance spectroscopy. The measured impedance spectra are found to be described well by an electrochemical model based on a generalized transmission model for a mixed conducting oxide, and all trends are consistent with a reaction pathway involving oxygen reduction over the LSM surface followed by diffusion through the film and into the electrolyte substrate. The surface activity is found to be correlated with the number of exposed grain boundary sites, which decreases with either increasing film thickness (at constant growth temperature) or increasing film growth temperature (at constant thickness). These findings suggest that exposed grain boundaries in LSM films are more active than exposed grains towards the rate-limiting surface process, and that oxygen ion diffusion through polycrystalline LSM films is faster than many prior studies have concluded.", "date": "2015-10-14", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "3", "number": "38", "publisher": "Royal Society of Chemistry", "pagerange": "19330-19345", "id_number": "CaltechAUTHORS:20150828-120355577", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150828-120355577", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-0520565" }, { "agency": "NSF", "grant_number": "EFRI-1038307" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Central University, Taiwan" }, { "agency": "W. M. Keck Foundation" }, { "agency": "NSF", "grant_number": "DMR-1121262" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/C5TA02428E", "primary_object": { "basename": "c5ta02428e1.pdf", "url": "https://authors.library.caltech.edu/records/we907-9rp23/files/c5ta02428e1.pdf" }, "related_objects": [ { "basename": "c5ta02428e.pdf", "url": "https://authors.library.caltech.edu/records/we907-9rp23/files/c5ta02428e.pdf" } ], "pub_year": "2015", "author_list": "Usiskin, Robert E.; Maruyama, Shingo; et al." }, { "id": "https://authors.library.caltech.edu/records/7wtcv-z1q73", "eprint_id": 60596, "eprint_status": "archive", "datestamp": "2023-08-20 08:39:03", "lastmod": "2023-10-24 16:42:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Webb-M-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Savoie-B-M", "name": { "family": "Savoie", "given": "Brett M." }, "orcid": "0000-0002-7039-4039" }, { "id": "Wang-Zhen-Gang", "name": { "family": "Wang", "given": "Zhen-Gang" }, "orcid": "0000-0002-3361-6114" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Chemically Specific Dynamic Bond Percolation Model for Ion Transport in Polymer Electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: June 30, 2015; Revised: August 12, 2015; Published online: September 25, 2015. \n\nThis research was supported by the Resnick Sustainability Institute and the National Science Foundation under DMREF Award NSF-CHE-1335486. We acknowledge computing resources from the National Energy Research Scientific Computing Center (DE-AC02-05CH11231). Additionally, we thank Umi Yamamoto, Geoffrey Coates, and Nitash Balsara for helpful discussions. \n\nThe authors declare no competing financial interest.\n\n

Supplemental Material - ma5b01437_si_001.pdf

Supplemental Material - ma5b01437_si_002.pdf

Supplemental Material - ma5b01437_si_003.mpg

Supplemental Material - ma5b01437_si_004.mpg

", "abstract": "We introduce a coarse-grained approach for characterizing the long-timescale dynamics of ion diffusion in general polymer electrolytes using input from short molecular dynamics trajectories. The approach includes aspects of the dynamic bond percolation model [ J. Chem. Phys. 1983, 79, 3133\u22123142] by treating ion diffusion in terms of hopping transitions on a fluctuating lattice. We extend this well-known approach by using short (i.e., 10 ns) molecular dynamics (MD) trajectories to predict the distribution of ion solvation sites that comprise the lattice and to predict the rate of hopping among the lattice sites. This yields a chemically specific dynamic bond percolation (CS-DBP) model that enables the description of long-timescale ion diffusion in polymer electrolytes at a computational cost that makes feasible the screening of candidate materials. We employ the new model to characterize lithium-ion diffusion properties in six polyethers that differ by oxygen content and backbone stiffness: poly(trimethylene oxide), poly(ethylene oxide-alt-trimethylene oxide), poly(ethylene oxide), poly(propylene oxide), poly(ethylene oxide-alt-methylene oxide), and poly(methylene oxide). Good agreement is observed between the predictions of the CS-DBP model and long-timescale atomistic MD simulations, thus providing validation of the model. Among the most striking results from this analysis is the unexpectedly good lithium-ion diffusivity of poly(trimethylene oxide-alt-ethylene oxide) by comparison to poly(ethylene oxide), which is widely used. Additionally, the model straightforwardly reveals a range of polymer features that lead to low lithium-ion diffusivity, including the competing effects of the density of solvation sites and polymer stiffness. These results illustrate the potential of the CS-DBP model to screen polymer electrolytes on the basis of ion diffusivity and to identify important design criteria.", "date": "2015-10-13", "date_type": "published", "publication": "Macromolecules", "volume": "48", "number": "19", "publisher": "American Chemical Society", "pagerange": "7346-7358", "id_number": "CaltechAUTHORS:20150929-202516731", "issn": "0024-9297", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150929-202516731", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1335486" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.macromol.5b01437", "primary_object": { "basename": "ma5b01437_si_004.mpg", "url": "https://authors.library.caltech.edu/records/7wtcv-z1q73/files/ma5b01437_si_004.mpg" }, "related_objects": [ { "basename": "ma5b01437_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7wtcv-z1q73/files/ma5b01437_si_001.pdf" }, { "basename": "ma5b01437_si_002.pdf", "url": "https://authors.library.caltech.edu/records/7wtcv-z1q73/files/ma5b01437_si_002.pdf" }, { "basename": "ma5b01437_si_003.mpg", "url": "https://authors.library.caltech.edu/records/7wtcv-z1q73/files/ma5b01437_si_003.mpg" } ], "pub_year": "2015", "author_list": "Webb, Michael A.; Savoie, Brett M.; et al." }, { "id": "https://authors.library.caltech.edu/records/zjvhw-mb970", "eprint_id": 61715, "eprint_status": "archive", "datestamp": "2023-08-20 08:30:59", "lastmod": "2023-10-25 15:40:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ager-J-W", "name": { "family": "Ager", "given": "Joel W." }, "orcid": "0000-0001-9334-9751" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Walczak-K-A", "name": { "family": "Walczak", "given": "Karl A." } }, { "id": "Sharp-I-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" } ] }, "title": "Experimental demonstrations of spontaneous, solar-driven photoelectrochemical water splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry. \n\nReceived 10 Feb 2015, Accepted 24 Mar 2015; First published online 24 Mar 2015. \n\nThe authors thank Dr Eric Miller for the inspiration to compile this review, and the members of the U.S. Department of Energy's Photoelectrochemical Working Group and Task 35 (Renewable Hydrogen) of the International Energy Agency's Hydrogen Implementing Agreement for helpful comments, suggestions, and discussions, especially Heli Wang, Keith Emery, and Tom Jaramillo. JWA, KAW, IDS, and MS were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. SA acknowledges support from the Department of Chemistry and the School of Physical Sciences at the University of California, Irvine. MS acknowledges the Resnick Institute for Sustainability for a graduate fellowship. A summary version of this review paper (DOI: 10.2172/1209500) can be found on the working group website http://energy.gov/eere/fuelcells/photoelectrochemicalworking-group). The STH efficiency tables and graph will be updated as the field progresses.\n\n

Published - c5ee00457h.pdf

Supplemental Material - c5ee00457h1_si.pdf

", "abstract": "Laboratory demonstrations of spontaneous photoelectrochemical (PEC) solar water splitting cells are reviewed. Reported solar-to-hydrogen (STH) conversion efficiencies range from <1% to 18%. The demonstrations are categorized by the number of photovoltaic junctions employed (2 or 3), photovoltaic junction type (solid\u2013solid or solid\u2013liquid) and the ability of the systems to produce separated reaction product streams. Demonstrations employing two photovoltaic (PV) junctions have the highest reported efficiencies of 12.4% and 18%, which are for cells that, respectively, do and do not contain a semiconductor\u2013liquid junction. These devices used PV components based on III\u2013V semiconductors; recently, a number of demonstrations with >10% STH efficiency using potentially less costly materials have been reported. Device stability is a major challenge for the field, as evidenced by lifetimes of less than 24 hours in all but a few reports. No globally accepted protocol for evaluating and certifying STH efficiencies and lifetimes exists. It is our recommendation that a protocol similar to that used by the photovoltaic community be adopted so that future demonstrations of solar PEC water splitting can be compared on equal grounds.", "date": "2015-10-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2811-2824", "id_number": "CaltechAUTHORS:20151029-125838701", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151029-125838701", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of California, Irvine" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c5ee00457h", "primary_object": { "basename": "c5ee00457h1_si.pdf", "url": "https://authors.library.caltech.edu/records/zjvhw-mb970/files/c5ee00457h1_si.pdf" }, "related_objects": [ { "basename": "c5ee00457h.pdf", "url": "https://authors.library.caltech.edu/records/zjvhw-mb970/files/c5ee00457h.pdf" } ], "pub_year": "2015", "author_list": "Ager, Joel W.; Shaner, Matthew R.; et al." }, { "id": "https://authors.library.caltech.edu/records/y51kf-4xb27", "eprint_id": 59572, "eprint_status": "archive", "datestamp": "2023-08-20 08:20:37", "lastmod": "2023-10-23 20:44:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "McKone-J-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Functional integration of Ni\u2013Mo electrocatalysts with Si microwire array photocathodes to simultaneously achieve high fill factors and light-limited photocurrent densities for solar-driven hydrogen evolution", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Royal Society of Chemistry 2015.\n\nReceived 05 Apr 2015, Accepted 13 Jul 2015; First published online 07 Aug 2015. \n\nThis article is part of themed collection: Fundamentals and Applications of Inorganic Chemistry.\n\nDevice modeling, fabrication and testing were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub supported through the Office of Science of the U.S. Department of Energy under award number DE-SC004993. Development of the Ni\u2013Mo nanopowder catalyst was supported by the National Science Foundation (NSF) Powering the Planet Center for Chemical Innovation (CHE-1305124) and by the Molecular Materials Research Center of the Beckman Institute at the California Institute of Technology. The authors acknowledge additional support by the Gordon and Betty Moore Foundation (GBMF1225). MRS acknowledges the Resnick Sustainability Institute for a graduate fellowship. JRM acknowledges the Department of Energy, Office of Science, for a graduate research fellowship and the Department of Energy, Office of Energy Efficiency and Renewable Energy, for a SunShot postdoctoral research award.\n\n

Published - c5ee01076d.pdf

Supplemental Material - suppc5ee01076d1.pdf

", "abstract": "An n+p-Si microwire array coupled with a two-layer catalyst film consisting of Ni\u2013Mo nanopowder and TiO_2 light-scattering nanoparticles has been used to simultaneously achieve high fill factors and light-limited photocurrent densities from photocathodes that produce H_2(g) directly from sunlight and water. The TiO_2 layer scattered light back into the Si microwire array, while optically obscuring the underlying Ni\u2013Mo catalyst film. In turn, the Ni\u2013Mo film had a mass loading sufficient to produce high catalytic activity, on a geometric area basis, for the hydrogen-evolution reaction. The best-performing microwire array devices prepared in this work exhibited short-circuit photocurrent densities of \u221214.3 mA cm^(\u22122), photovoltages of 420 mV, and a fill factor of 0.48 under 1 Sun of simulated solar illumination, whereas the equivalent planar Ni\u2013Mo-coated Si device, without TiO_2 scatterers, exhibited negligible photocurrent due to complete light blocking by the Ni\u2013Mo catalyst layer.", "date": "2015-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2977-2984", "id_number": "CaltechAUTHORS:20150814-170845573", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150814-170845573", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC004993" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "1225" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C5EE01076D", "primary_object": { "basename": "suppc5ee01076d1.pdf", "url": "https://authors.library.caltech.edu/records/y51kf-4xb27/files/suppc5ee01076d1.pdf" }, "related_objects": [ { "basename": "c5ee01076d.pdf", "url": "https://authors.library.caltech.edu/records/y51kf-4xb27/files/c5ee01076d.pdf" } ], "pub_year": "2015", "author_list": "Shaner, Matthew R.; McKone, James R.; et al." }, { "id": "https://authors.library.caltech.edu/records/m0k7j-kqf73", "eprint_id": 59300, "eprint_status": "archive", "datestamp": "2023-08-22 16:24:27", "lastmod": "2023-10-23 20:17:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yiyang", "name": { "family": "Liu", "given": "Yiyang" } }, { "id": "Virgil-Scott-C", "name": { "family": "Virgil", "given": "Scott C." }, "orcid": "0000-0001-8586-5641" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Palladium-Catalyzed Decarbonylative Dehydration for the Synthesis of \u03b1-Vinyl Carbonyl Compounds and Total Synthesis of (\u2212)-Aspewentins A, B, and C", "ispublished": "pub", "full_text_status": "public", "keywords": "enantioselectivity; natural products; olefination; palladium; total synthesis", "note": "\u00a9 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: June 6, 2015. Article first published online: 29 July 2015. \n\nWe wish to thank the Resnick Sustainability Institute at Caltech (graduate fellowship to Y.L.), NIH (R01M080269 to B.M.S., 5R01M031332-27 to R.H.G.), the Gordon and Betty Moore Foundation, the Caltech Center for Catalysis and Chemical Synthesis, and Caltech for financial support. Dr. David VanderVelde is acknowledged for assistance with NMR spectroscopy. Dr. Mona Shahgholi and Naseem Torian are acknowledged for assistance with high-resolution mass spectrometry. We would like to thank Prof. Richmond Sarpong of UC Berkeley for helpful discussions.\n\n

Accepted Version - nihms732630.pdf

Supplemental Material - anie_201505161_sm_miscellaneous_information.pdf

", "abstract": "The direct \u03b1-vinylation of carbonyl compounds to form a quaternary stereocenter is a challenging transformation. It was discovered that \u03b4-oxocarboxylic acids can serve as masked vinyl compounds and be unveiled by palladium-catalyzed decarbonylative dehydration. The carboxylic acids are readily available through enantioselective acrylate addition or asymmetric allylic alkylation. A variety of \u03b1-vinyl quaternary carbonyl compounds are obtained in good yields, and an application in the first enantioselective total synthesis of (\u2212)-aspewentins A, B, and C is demonstrated.", "date": "2015-09-28", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "54", "number": "40", "publisher": "Wiley", "pagerange": "11800-11803", "id_number": "CaltechAUTHORS:20150807-083400322", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150807-083400322", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "R01M080269-01" }, { "agency": "NIH", "grant_number": "5R01M031332-27" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201505161", "pmcid": "PMC4686263", "primary_object": { "basename": "anie_201505161_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/m0k7j-kqf73/files/anie_201505161_sm_miscellaneous_information.pdf" }, "related_objects": [ { "basename": "nihms732630.pdf", "url": "https://authors.library.caltech.edu/records/m0k7j-kqf73/files/nihms732630.pdf" } ], "pub_year": "2015", "author_list": "Liu, Yiyang; Virgil, Scott C.; et al." }, { "id": "https://authors.library.caltech.edu/records/5h1p1-dnz43", "eprint_id": 80069, "eprint_status": "archive", "datestamp": "2023-08-20 08:03:17", "lastmod": "2023-10-17 15:28:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bose-Subhonmesh", "name": { "family": "Bose", "given": "Subhonmesh" }, "orcid": "0000-0002-3445-4479" }, { "id": "Gayme-D-F", "name": { "family": "Gayme", "given": "Dennice F." } }, { "id": "Chandy-K-M", "name": { "family": "Chandy", "given": "K. Mani" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Quadratically Constrained Quadratic Programs on Acyclic Graphs With Application to Power Flow", "ispublished": "pub", "full_text_status": "public", "keywords": "Conic relaxation, semidefinite programming, optimal power flow", "note": "\u00a9 2015 IEEE. \n\nManuscript received April 8, 2014; revised September 28, 2014; accepted November 17, 2014. Date of publication February 6, 2015; date of current version September 14, 2015. \n\nThis work was supported in part by the National Science Foundation through NetSE CNS 0911041, in part by the ARPA-E through GENI DE AR0000226, in part by Southern California Edison, in part by the National Science Council of Taiwan through NSC 103-3113-P-008-001, in part by the Los Alamos National Lab (DoE), and in part by the Caltech's Resnick Institute. Recommended by Associate Editor M. Chertkov.\n\n

Submitted - 1203.5599.pdf

", "abstract": "This paper proves that nonconvex quadratically constrained quadratic programs can be solved in polynomial time when their underlying graph is acyclic, provided the constraints satisfy a certain technical condition. We demonstrate this theory on optimal power-flow problems over tree networks.", "date": "2015-09", "date_type": "published", "publication": "IEEE Transactions on Control of Network Systems", "volume": "2", "number": "3", "publisher": "IEEE", "pagerange": "278-287", "id_number": "CaltechAUTHORS:20170810-100823060", "issn": "2325-5870", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170810-100823060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0911041" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TCNS.2015.2401172", "primary_object": { "basename": "1203.5599.pdf", "url": "https://authors.library.caltech.edu/records/5h1p1-dnz43/files/1203.5599.pdf" }, "pub_year": "2015", "author_list": "Bose, Subhonmesh; Gayme, Dennice F.; et al." }, { "id": "https://authors.library.caltech.edu/records/9ayqz-pdm47", "eprint_id": 59808, "eprint_status": "archive", "datestamp": "2023-08-20 07:56:54", "lastmod": "2023-10-23 22:44:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bose-Subhonmesh", "name": { "family": "Bose", "given": "Subhonmesh" }, "orcid": "0000-0002-3445-4479" }, { "id": "Wu-Chenye", "name": { "family": "Wu", "given": "Chenye" } }, { "id": "Xu-Yunjian", "name": { "family": "Xu", "given": "Yunjian" } }, { "id": "Wierman-A", "name": { "family": "Wierman", "given": "Adam" } }, { "id": "Mohsenian-Rad-H", "name": { "family": "Mohsenian-Rad", "given": "Hamed" } } ] }, "title": "A Unifying Market Power Measure for Deregulated Transmission-Constrained Electricity Markets", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Electricity markets, market power", "note": "\u00a9 2015 IEEE.\n\nManuscript received November 28, 2013; revised April 25, 2014 and August\n01, 2014; accepted September 09, 2014. Date of publication October 23,\n2014; date of current version July 17, 2015. \n\nThis work was supported in part by\nNSF through EPAS 1307794, ECCS 1307756, NetSE CNS 0911041, ARPA-E\nthrough GENI DE-AR0000226, Southern California Edison, the National Science\nCouncil of Taiwan through NSC 103- 3113-P-008-001, the Los Alamos\nNational Lab (DoE), and Caltech's Resnick Institute. Paper no. TPWRS-01531-\n2013.\n\nThe authors would like to thank Dr. N. Fromer and Mr.\nP. DeMartini from Resnick Institute at Caltech for their helpful\ncomments. The authors also would like to thank Prof. A. Conejo\n(Editor-in-Chief) and the anonymous reviewers for their inputs.", "abstract": "Market power assessment is a prime concern when designing a deregulated electricity market. In this paper, we propose a new functional market power measure, termed transmission constrained network flow (TCNF), that unifies three large classes of transmission constrained structural market power indices in the literature: residual supply based, network flow based, and minimal generation based. Furthermore, it is suitable for demand-response and renewable integration and hence more amenable to identifying market power in the future smart grid. The measure is defined abstractly, and allows incorporation of power flow equations in multiple ways; we investigate the current market operations using a DC approximation and further explore the possibility of including detailed AC power flow models through semidefinite relaxation, and interior-point algorithms from Matpower. Finally, we provide extensive simulations on IEEE benchmark systems and highlight the complex interaction of engineering constraints with market power assessment.", "date": "2015-09", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "30", "number": "5", "publisher": "IEEE", "pagerange": "2338-2348", "id_number": "CaltechAUTHORS:20150821-103411487", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150821-103411487", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EPAS 1307794" }, { "agency": "NSF", "grant_number": "ECCS 1307756" }, { "agency": "NetSE", "grant_number": "CNS 0911041" }, { "agency": "ARPA-E", "grant_number": "GENI DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Los Alamos National Laboratory" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2014.2360216", "pub_year": "2015", "author_list": "Bose, Subhonmesh; Wu, Chenye; et al." }, { "id": "https://authors.library.caltech.edu/records/vexp2-v8d31", "eprint_id": 60069, "eprint_status": "archive", "datestamp": "2023-08-20 07:49:35", "lastmod": "2023-10-24 14:51:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Guan-Dabo", "name": { "family": "Guan", "given": "Dabo" } }, { "id": "Wei-Wei", "name": { "family": "Wei", "given": "Wei" }, "orcid": "0000-0002-1018-7708" }, { "id": "Davis-S-J", "name": { "family": "Davis", "given": "Steven J." }, "orcid": "0000-0002-9338-0844" }, { "id": "Ciais-P", "name": { "family": "Ciais", "given": "Philippe" }, "orcid": "0000-0001-8560-4943" }, { "id": "Bai-Jin", "name": { "family": "Bai", "given": "Jin" } }, { "id": "Peng-Shushi", "name": { "family": "Peng", "given": "Shushi" }, "orcid": "0000-0001-5098-726X" }, { "id": "Zhang-Qiang", "name": { "family": "Zhang", "given": "Qiang" }, "orcid": "0000-0002-8376-131X" }, { "id": "Hubacek-K", "name": { "family": "Hubacek", "given": "Klaus" }, "orcid": "0000-0003-2561-6090" }, { "id": "Garland-G", "name": { "family": "Garland", "given": "Gregg" } }, { "id": "Andres-R-J", "name": { "family": "Andres", "given": "Robert J." } }, { "id": "Crawford-Brown-D", "name": { "family": "Crawford-Brown", "given": "Douglas" } }, { "id": "Lin-Jintai", "name": { "family": "Lin", "given": "Jintai" } }, { "id": "Zhao-Hongyan", "name": { "family": "Zhao", "given": "Hongyan" } }, { "id": "Hong-Chaopeng", "name": { "family": "Hong", "given": "Chaopeng" } }, { "id": "Boden-T-A", "name": { "family": "Boden", "given": "Thomas A." } }, { "id": "Feng-Kuishuang", "name": { "family": "Feng", "given": "Kuishuang" }, "orcid": "0000-0001-5139-444X" }, { "id": "Peters-G-P", "name": { "family": "Peters", "given": "Glen P." } }, { "id": "Xi-Fengming", "name": { "family": "Xi", "given": "Fengming" } }, { "id": "Liu-Junguo", "name": { "family": "Liu", "given": "Junguo" } }, { "id": "Lin-Yuan", "name": { "family": "Li", "given": "Yuan" } }, { "id": "Zhao-Yu", "name": { "family": "Zhao", "given": "Yu" } }, { "id": "Zeng-Ning", "name": { "family": "Zeng", "given": "Ning" } }, { "id": "He-Kevin", "name": { "family": "He", "given": "Kevin" }, "orcid": "0000-0001-5806-0370" } ] }, "title": "Reduced carbon emission estimates from fossil fuel\n combustion and cement production in China", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate-change mitigation, Sustainability, Climate-change policy", "note": "\u00a9 2015 Macmillan Publishers Limited. \n\nReceived 24 November 2014. Accepted 10 June 2015. Published online 19 August 2015.\n\nThis work was supported by the Strategic Priority Research\nProgram \"Climate Change: Carbon Budget and Relevant Issues\" of the Chinese Academy of Sciences, and by China's National Basic Research Program and National Natural Science Foundation of China (NSFC) funded projects (grants XDA05010109, 2014CB441301, XDA05010110, XDA05010103, XDA05010101, 41328008 and 41222036). Z.L. acknowledges Harvard University Giorgio Ruffolo fellowship and\nsupport from Italy's Ministry for Environment, Land and Sea. D.G. acknowledges the Economic and Social Research Council funded project \"Dynamics of Green Growth in\nEuropean and Chinese Cities\" (ES/L016028) and the Philip Leverhulme Prize. S.J.D. acknowledges support from the Institute of Applied Ecology, Chinese Academy of\nSciences Fellowships for Young International Distinguished Scientists. P.C. and S.P. acknowledge support of the European Research Council Synergy grant ERC-2013-SyG 610028-IMBALANCE-P. R.J.A. and T.A.B. were sponsored by the US Department of Energy, Office of Science, Biological and Environmental Research under US Department of Energy contract DE-AC05-00OR22725. J. Lin acknowledges the NSFC\n(41422502 and 41175127). J. Liu acknowledges the International Science & Technology Cooperation Program of China (2012DFA91530), the NSFC (41161140353, 91425303), The Natural Science Foundation of Beijing, China (8151002), the National Program for Support of Top-notch Young Professionals, and Fundamental Research Funds for the Central Universities (TD-JC-2013-2). F.X. acknowledges the NSFC (41473076), China CDM Fund (2013051, 2013124) and\nShenyang Science and Technology Planning (F14-232-6-01, F14-134-9-00). G.P.P. acknowledges funding from the Norwegian Research Council (235523). The authors are grateful to S. Piao, L. Cao and J. Yan for insightful comments.\n\n

Supplemental Material - nature14677-s1.pdf

Supplemental Material - nature14677-s2.xlsx

", "abstract": "Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000\u20132012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO_2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = \u00b17.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000\u20132013 may be larger than China's estimated total forest sink in 1990\u20132007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000\u20132009 (2.6 gigatonnes of carbon).", "date": "2015-08-20", "date_type": "published", "publication": "Nature", "volume": "524", "number": "7565", "publisher": "Nature Publishing Group", "pagerange": "335-338", "id_number": "CaltechAUTHORS:20150904-094021650", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150904-094021650", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Chinese Academy of Sciences" }, { "agency": "China's National Basic Research Program" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "XDA05010109" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "2014CB441301" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "XDA05010110" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "XDA05010103" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "XDA05010101" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "41328008" }, { "agency": "Harvard University Giorgio Ruffolo fellowship" }, { "agency": "Ministry for Environment, Land and Sea (Italy)" }, { "agency": "Economic and Social Research Council funded project \"Dynamics of Green Growth in European and Chinese Cities\"", "grant_number": "ES/L016028" }, { "agency": "Philip Leverhulme Prize" }, { "agency": "Institute of Applied Ecology" }, { "agency": "Chinese Academy of Sciences Fellowships for Young International Distinguished Scientists" }, { "agency": "European Research Council Synergy grant", "grant_number": "ERC-2013-SyG 610028-IMBALANCE-P" }, { "agency": "Department of Energy (DOE) Office of Science", "grant_number": "DE-AC05-00OR22725" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "41422502" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "41175127" }, { "agency": "International Science & Technology Cooperation Program of China", "grant_number": "2012DFA91530" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "41161140353" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "91425303" }, { "agency": "Natural Science Foundation of Beijing, China", "grant_number": "8151002" }, { "agency": "National Program for Support of Top-notch Young Professionals" }, { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "TD-JC-2013-2" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "41473076" }, { "agency": "China CDM Fund", "grant_number": "2013051" }, { "agency": "China CDM Fund", "grant_number": "2013124" }, { "agency": "Shenyang Science and Technology Planning", "grant_number": "F14-232-6-01" }, { "agency": "Shenyang Science and Technology Planning", "grant_number": "F14-134-9-00" }, { "agency": "Norwegian Research Council", "grant_number": "235523" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nature14677", "primary_object": { "basename": "nature14677-s2.xlsx", "url": "https://authors.library.caltech.edu/records/vexp2-v8d31/files/nature14677-s2.xlsx" }, "related_objects": [ { "basename": "nature14677-s1.pdf", "url": "https://authors.library.caltech.edu/records/vexp2-v8d31/files/nature14677-s1.pdf" } ], "pub_year": "2015", "author_list": "Liu, Zhu; Guan, Dabo; et al." }, { "id": "https://authors.library.caltech.edu/records/4t24d-qh118", "eprint_id": 60181, "eprint_status": "archive", "datestamp": "2023-08-20 07:47:28", "lastmod": "2023-10-24 14:57:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Diallo-M-S", "name": { "family": "Diallo", "given": "Mamadou S." }, "orcid": "0000-0002-2571-1568" }, { "id": "Baier-G", "name": { "family": "Baier", "given": "Gretchen" } }, { "id": "Moyer-B-A", "name": { "family": "Moyer", "given": "Bruce A." } }, { "id": "Hamelers-B", "name": { "family": "Hamelers", "given": "Bert" } } ] }, "title": "Critical Materials Recovery from Solutions and Wastes: Retrospective and Outlook", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 American Chemical Society.\n\nPublished: August 18, 2015.\n\nThe theme and content of this special ES&T issue were derived from the presentations and discussion during a Presidential Symposium on \"Separation Science and Technology as a Convergence Platform for SusChEM\" that was held on August 12-13 during the 248th National Meeting of the American Chemical Society (ACS) in San Francisco (CA). This symposium was organized and chaired by the guest editors of this special issue. We would to take this opportunity to thank our conference co-Chair Dr. Catherine T. \"Katie\" Hunt (Dow Retired and Past ACS President) and organizing committee members Dr. Darlene Shuster and Mr. Derrick Wu of the American Institute of Chemical Engineers (AIChE) for their dedication, hard work and contributions to the success of our symposium. We thank all the sponsors who provided funding and/or in-kind support to our symposium including: NSF CBET (Award No. 1446444); ACS [President (PRES), Corporation Associates (CA), Committee on Environmental Improvement (CEI), Committee on Science (COMSCI), Division of Analytical Chemistry (ANYL), Division of Environmental Chemistry (ENVR), and the Multidisciplinary Program Planning Group (MPPG)]; AIChE; the Resnick Institute (Caltech); The Dow Chemical Company; and the Critical Materials Institute (CMI), an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office. \n\nViews expressed in this editorial are those of the authors and not necessarily the views of the ACS. \n\nThe authors declare no competing financial interest.", "abstract": "One of the greatest challenges facing society in the 21st\ncentury is providing better living standards to all people\nwhile reducing and minimizing the impact of human activities\non Earth's global environment and climate. During the past\ndecade, sustainability has emerged as a unifying framework for\naddressing the global environmental, economic, and societal\nchallenges facing the world. The Brundtland Commission of\nthe United Nations defined \"sustainable development\" as \"that\nwhich meets the needs of the present without compromising\nthe ability of future generations to meet their own needs\"\n(available online at http://www.un-documents.net/ocf-02.htm). Materials are the building blocks and pillars of a\nsustainable society and global economy. There is a growing\nrealization that the implementation of clean-energy technologies\nof the 21st century will require large amounts of critical\nmetals including rare-earth elements (REEs), platinum group\nmetals, copper, lithium, gallium, and precious metals (e.g., silver\nand gold). Significant amounts of phosphorus (P) will also be\nneeded as the world faces the daunting challenge of doubling\nthe amount of food it currently produces in order to feed\naround 9 billion people by 2050. As a society, we utilize and\nconsume large amounts of minerals, metals, P, and other\nmaterials produced by mining with little or no recycling. Thus,\nour current management and stewardship of Earth's mineral\nand metal resources are not sustainable. Increasingly, impaired\nwater (e.g., seawater, brines, and municipal/industrial wastewater)\nand solid wastes (e.g., discarded consumer products and\nsludge) are being viewed as alternative sources of critical metals\nand valuable elements to address global materials availability\nand supply challenges. Thus, in the next decades, environmental\nscientists/engineers, business leaders, and policy/\ndecision makers will be confronted with a new set of exciting\nopportunities and challenges to advance the viability of critical\nmaterials recovery from impaired water and solid wastes. In this\nspecial issue of Environmental Science & Technology (ES&T), we\nhighlight recent advances on the recovery of critical/valuable\nmetals and P from \"wastes\". Two key goals of this special issue\nare to (1) provide a retrospective and outlook of the state-of-the-field; and (2) bring into focus crosscutting scientific,\ntechnological, and environmental challenges along with\ncorresponding societal and regulatory issues.", "date": "2015-08-18", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "49", "number": "16", "publisher": "American Chemical Society", "pagerange": "9387-9389", "id_number": "CaltechAUTHORS:20150911-090344763", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150911-090344763", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CBET-1446444" }, { "agency": "American Chemical Society" }, { "agency": "AIChE" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "Critical Materials Institute (CMI)" }, { "agency": "Department of Energy (DOE)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.est.5b03694", "pub_year": "2015", "author_list": "Diallo, Mamadou S.; Baier, Gretchen; et al." }, { "id": "https://authors.library.caltech.edu/records/83r5y-rs592", "eprint_id": 58999, "eprint_status": "archive", "datestamp": "2023-08-20 07:22:45", "lastmod": "2023-10-23 19:57:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Webb-Michael-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Jung-Yukyung", "name": { "family": "Jung", "given": "Yukyung" } }, { "id": "Pesko-Danielle-M", "name": { "family": "Pesko", "given": "Danielle M." }, "orcid": "0000-0002-4833-0119" }, { "id": "Savoie-Brett-M", "name": { "family": "Savoie", "given": "Brett M." }, "orcid": "0000-0002-7039-4039" }, { "id": "Yamamoto-Umi", "name": { "family": "Yamamoto", "given": "Umi" } }, { "id": "Coates-Geoffrey-W", "name": { "family": "Coates", "given": "Geoffrey W." }, "orcid": "0000-0002-3400-2552" }, { "id": "Balsara-Nitash-P", "name": { "family": "Balsara", "given": "Nitash P." }, "orcid": "0000-0002-0106-5565" }, { "id": "Wang-Zhen-Gang", "name": { "family": "Wang", "given": "Zhen-Gang" }, "orcid": "0000-0002-3361-6114" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Systematic Computational and Experimental Investigation of Lithium-Ion Transport Mechanisms in Polyester-Based Polymer Electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: May 21, 2015; Published: July 10, 2015. \n\nThis research was supported by the National Science Foundation under DMREF Award Number NSF-CHE-1335486. M.A.W. also acknowledges support from the Resnick Sustainability Institute.\n\n

Published - acscentsci.5b00195.pdf

Supplemental Material - oc5b00195_si_001.pdf

", "abstract": "Understanding the mechanisms of lithium-ion transport in polymers is crucial for the design of polymer electrolytes. We combine modular synthesis, electrochemical characterization, and molecular simulation to investigate lithium-ion transport in a new family of polyester-based polymers and in poly(ethylene oxide) (PEO). Theoretical predictions of glass-transition temperatures and ionic conductivities in the polymers agree well with experimental measurements. Interestingly, both the experiments and simulations indicate that the ionic conductivity of PEO, relative to the polyesters, is far higher than would be expected from its relative glass-transition temperature. The simulations reveal that diffusion of the lithium cations in the polyesters proceeds via a different mechanism than in PEO, and analysis of the distribution of available cation solvation sites in the various polymers provides a novel and intuitive way to explain the experimentally observed ionic conductivities. This work provides a platform for the evaluation and prediction of ionic conductivities in polymer electrolyte materials.", "date": "2015-07-22", "date_type": "published", "publication": "ACS Central Science", "volume": "1", "number": "4", "publisher": "American Chemical Society", "pagerange": "198-205", "id_number": "CaltechAUTHORS:20150724-073254175", "issn": "2374-7943", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150724-073254175", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1335486" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscentsci.5b00195", "pmcid": "PMC4827473", "primary_object": { "basename": "oc5b00195_si_001.pdf", "url": "https://authors.library.caltech.edu/records/83r5y-rs592/files/oc5b00195_si_001.pdf" }, "related_objects": [ { "basename": "acscentsci.5b00195.pdf", "url": "https://authors.library.caltech.edu/records/83r5y-rs592/files/acscentsci.5b00195.pdf" } ], "pub_year": "2015", "author_list": "Webb, Michael A.; Jung, Yukyung; et al." }, { "id": "https://authors.library.caltech.edu/records/cadg7-6ma48", "eprint_id": 59823, "eprint_status": "archive", "datestamp": "2023-08-20 07:19:54", "lastmod": "2023-10-23 22:45:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Borup-K-A", "name": { "family": "Borup", "given": "Kasper A." } }, { "id": "Fischer-K-F-F", "name": { "family": "Fischer", "given": "Karl F. F." } }, { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" }, { "id": "Iversen-B-B", "name": { "family": "Iversen", "given": "Bo B." } } ] }, "title": "Measuring anisotropic resistivity of single crystals using the van der Pauw technique", "ispublished": "pub", "full_text_status": "public", "note": "\u00a92015 American Physical Society. \n\n(Received 11 February 2015; revised manuscript received 16 June 2015; published 24 July 2015) \n\nThe work was supported by the Danish National Research Foundation, Grant No. DNRF93 (Center for Materials Crystallography, DNRF93). K.A.B. is thankful for funding from the Danish Council for Independent Research (DFF), Grant No. 4090-00071, and the DFF Sapere Aude program. D.R.B. would like to acknowledge the support of the Resnick Sustainability Institute.\n\n

Published - PhysRevB.92.045210.pdf

Supplemental Material - Supporting_information.pdf

", "abstract": "Anisotropy in properties of materials is important in materials science and solid-state physics. Measurement of the full resistivity tensor of crystals using the standard four-point method with bar shaped samples requires many measurements and may be inaccurate due to misalignment of the bars along crystallographic directions. Here an approach to extracting the resistivity tensor using van der Pauw measurements is presented. This reduces the number of required measurements. The theory of the van der Pauw method is extended to extract the tensor from parallelogram shaped samples with known geometry. Methods to extract the tensor for both known and unknown principal axis orientation are presented for broad applicability to single crystals. Numerical simulations of errors are presented to quantify error sources. Several benchmark experiments are performed on isotropic graphite samples to verify the internal consistency of the developed theory, test experimental precision, and characterize error sources. The presented methods are applied to a RuSb_2 single crystal at room temperature and the results are discussed based on the error source analysis. Temperature resolved resistivities along the a and b directions are finally reported and briefly discussed.", "date": "2015-07-15", "date_type": "published", "publication": "Physical Review B", "volume": "92", "number": "4", "publisher": "American Physical Society", "pagerange": "Art. No. 045210", "id_number": "CaltechAUTHORS:20150821-160740952", "issn": "1098-0121", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150821-160740952", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Danish National Research Foundation (DNRF)", "grant_number": "DNRF93" }, { "agency": "Danish Council for Independent Research (DFF)", "grant_number": "4090-00071" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.92.045210", "primary_object": { "basename": "PhysRevB.92.045210.pdf", "url": "https://authors.library.caltech.edu/records/cadg7-6ma48/files/PhysRevB.92.045210.pdf" }, "related_objects": [ { "basename": "Supporting_information.pdf", "url": "https://authors.library.caltech.edu/records/cadg7-6ma48/files/Supporting_information.pdf" } ], "pub_year": "2015", "author_list": "Borup, Kasper A.; Fischer, Karl F. F.; et al." }, { "id": "https://authors.library.caltech.edu/records/8dht5-v2y46", "eprint_id": 58947, "eprint_status": "archive", "datestamp": "2023-08-20 07:04:10", "lastmod": "2023-10-23 19:54:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Arayba-D-B", "name": { "family": "Araya", "given": "Daniel B." } }, { "id": "Dabiri-J-O", "name": { "family": "Dabiri", "given": "John O." }, "orcid": "0000-0002-6722-9008" } ] }, "title": "A comparison of wake measurements in motor-driven and flow-driven turbine experiments", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 Springer-Verlag Berlin Heidelberg.\n\nReceived: 17 February 2015; Revised: 9 June 2015; Accepted: 25 June 2015.\n\nThis work was funded by an NSF Graduate Research Fellowship as well as the Caltech Resnick Institute Graduate Fellowship to D.B.A. Funding to J.O.D. from the Gordon and Betty Moore Foundation through Grant No. GBMF2645 and the Office of Naval Research through Grant N000141211047 are also gratefully acknowledged.", "abstract": "We present experimental data to compare and contrast the wake characteristics of a turbine whose rotation is either driven by the oncoming flow or prescribed by a motor. Velocity measurements are collected using two-dimensional particle image velocimetry in the near-wake region of a lift-based, vertical-axis turbine. The wake of this turbine is characterized by a spanwise asymmetric velocity profile which is found to be strongly dependent on the turbine tip speed ratio (TSR), while only weakly dependent on Reynolds number (Re). For a given Re, the TSR is controlled either passively by a mechanical brake or actively by a DC motor. We find that there exists a finite region in TSR versus Re space where the wakes of the motor-driven turbine and flow-driven turbine are indistinguishable to within experimental precision. Outside of this region, the sign of the net circulation in the wake changes as TSR is increased by the motor. Shaft torque measurements show a corresponding sign change above this TSR threshold set by circulation, indicating a transition from net torque due to lift to net torque due to drag produced by the turbine blades, the latter of which can give wake measurements that are inconsistent with a flow-driven turbine. The results support the claim that the turbine kinematics and aerodynamic properties are the sole factors that govern the dynamics of its wake, irrespective of the means to move the turbine blades. This has significance for both experimental and computational studies where it may be necessary, or perhaps more economical, to prescribe the turbine kinematics in order to analyze its aerodynamic characteristics.", "date": "2015-07", "date_type": "published", "publication": "Experiments in Fluids", "volume": "56", "number": "7", "publisher": "Springer", "pagerange": "Art. No. 150", "id_number": "CaltechAUTHORS:20150720-130414126", "issn": "0723-4864", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150720-130414126", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2645" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N000141211047" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1007/s00348-015-2022-7", "pub_year": "2015", "author_list": "Araya, Daniel B. and Dabiri, John O." }, { "id": "https://authors.library.caltech.edu/records/9n9xf-9jt50", "eprint_id": 60646, "eprint_status": "archive", "datestamp": "2023-08-20 06:54:47", "lastmod": "2023-10-24 21:03:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cahn-Jackson-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." }, "orcid": "0000-0001-8849-4516" }, { "id": "Brinkmann-Chen-Sabine", "name": { "family": "Brinkmann-Chen", "given": "Sabine" }, "orcid": "0000-0002-5419-4192" }, { "id": "Spatzal-Thomas", "name": { "family": "Spatzal", "given": "Thomas" }, "orcid": "0000-0002-9136-5915" }, { "id": "Wiig-Jared-A", "name": { "family": "Wiig", "given": "Jared A." } }, { "id": "Buller-Andrew-R", "name": { "family": "Buller", "given": "Andrew R." }, "orcid": "0000-0002-9635-4844" }, { "id": "Einsle-Oliver", "name": { "family": "Einsle", "given": "Oliver" }, "orcid": "0000-0001-8722-2893" }, { "id": "Hu-Yilin", "name": { "family": "Hu", "given": "Yilin" } }, { "id": "Ribbe-Markus-W", "name": { "family": "Ribbe", "given": "Markus W." }, "orcid": "0000-0002-7366-1526" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Cofactor specificity motifs and the induced fit mechanism in class I ketol-acid reductoisomerases", "ispublished": "pub", "full_text_status": "public", "keywords": "acetohydroxyacid isomeroreductase (AHAIR),\ncofactor binding, conformational change, crystal structure,\nketol-acid reductoisomerase (KARI)", "note": "\u00a9 2015 The Authors Journal compilation \u00a9 2015 Biochemical Society. \n\nReceived 11 February 2015/1 April 2015; accepted 7 April 2015. Published as BJ Immediate Publication 7 April 2015, doi:10.1042/BJ20150183 \n\nThis work was supported by the Gordon and Betty Moore Foundation [grant number GBMF2809] to the Caltech Programmable Molecular Technology Initiative; the Resnick Sustainability Institute at Caltech (to J.K.B.C.); the National Institute of Health [grant number GM 67626 (to M.W.R.)]; the Molecular Observatory is supported by the Gordon and Betty Moore Foundation, the Beckman Institute, and the Sanofi-Aventis Bioengineering Research Program at Caltech. \n\nWe thank Dr Jens Kaiser and Pavle Nikolovski for their continued support. \n\nAUTHOR CONTRIBUTION: Jackson Cahn and Sabine Brinkmann-Chen conceived of the project. Sabine Brinkmann-Chen prepared and crystallized three proteins, Jackson Cahn one and Jared Wiig and Thomas Spatzal one. Jackson Cahn solved the protein crystal structures, one in collaboration with Thomas Spatzal and one with Andrew Buller; Yilin Hu and Markus Ribbe provided guidance to Jared Wiig, Oliver Einsle to Thomas Spatzal and Frances Arnold to Jackson Cahn, Sabine Brinkmann-Chen and Andrew Buller. Sabine Brinkmann-Chen measured the thermostability of one of the KARIs; Jackson Cahn analysed the crystal structures and prepared the figures; Jackson Cahn, Sabine Brinkmann-Chen, Andrew Buller and Frances Arnold wrote the manuscript.\n\nCoordinates and structure factors have been deposited in the Protein Data Bank with accession numbers 4TSK, 4XDY, 4XDZ, 4XEH and 4XIY, as shown in Table 1.\n\n

Accepted Version - nihms690011.pdf

Supplemental Material - bj4680475ntsadd.pdf

", "abstract": "Although most sequenced members of the industrially important ketol-acid reductoisomerase (KARI) family are class I enzymes, structural studies to date have focused primarily on the class II KARIs, which arose through domain duplication. In the present study, we present five new crystal structures of class I KARIs. These include the first structure of a KARI with a six-residue \u03b22\u03b1B (cofactor specificity determining) loop and an NADPH phosphate-binding geometry distinct from that of the seven- and 12-residue loops. We also present the first structures of naturally occurring KARIs that utilize NADH as cofactor. These results show insertions in the specificity loops that confounded previous attempts to classify them according to loop length. Lastly, we explore the conformational changes that occur in class I KARIs upon binding of cofactor and metal ions. The class I KARI structures indicate that the active sites close upon binding NAD(P)H, similar to what is observed in the class II KARIs of rice and spinach and different from the opening of the active site observed in the class II KARI of Escherichia coli. This conformational change involves a decrease in the bending of the helix that runs between the domains and a rearrangement of the nicotinamide-binding site.", "date": "2015-06-15", "date_type": "published", "publication": "Biochemical Journal", "volume": "468", "number": "3", "publisher": "Biochemical Society", "pagerange": "475-484", "id_number": "CaltechAUTHORS:20151001-082128409", "issn": "0264-6021", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151001-082128409", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2809" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NIH", "grant_number": "GM 67626" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Caltech Sanofi-Aventis Bioengineering Research Program" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1042/BJ20150183", "pmcid": "PMC4550535", "primary_object": { "basename": "bj4680475ntsadd.pdf", "url": "https://authors.library.caltech.edu/records/9n9xf-9jt50/files/bj4680475ntsadd.pdf" }, "related_objects": [ { "basename": "nihms690011.pdf", "url": "https://authors.library.caltech.edu/records/9n9xf-9jt50/files/nihms690011.pdf" } ], "pub_year": "2015", "author_list": "Cahn, Jackson K. B.; Brinkmann-Chen, Sabine; et al." }, { "id": "https://authors.library.caltech.edu/records/nzefd-4mg84", "eprint_id": 57997, "eprint_status": "archive", "datestamp": "2023-09-15 05:02:35", "lastmod": "2023-10-23 21:12:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ning-Xin", "name": { "family": "Ning", "given": "Xin" }, "orcid": "0000-0002-9432-3665" }, { "id": "Pellegrino-S", "name": { "family": "Pellegrino", "given": "Sergio" }, "orcid": "0000-0001-9373-3278" } ] }, "title": "Imperfection-insensitive axially loaded thin cylindrical shells", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Shell buckling; Imperfection-sensitivity; Corrugated shells; Structural optimization; Mass efficiency; Aster shell", "note": "\u00a9 2015 Elsevier Ltd.\n\nReceived 19 November 2013; Received in revised form 2 December 2014; Available online 7 February 2015. \n\nWe thank Professors J.-F. Jullien, P. Koumoutsakos, M.M. Mikulas and E. Ramm for help and advice during the course of this study. We also thank Professors C.R. Calladine, P. Ermanni, J. Hutchinson, K.-C. Park, A.M. Waas and P. Weaver for comments on a preliminary version of this study, presented at the AIAA 54th SDM Conference. J. Steeves provided the lamina properties in Section 4.1. Financial support from the Resnick Institute at the California Institute of Technology is gratefully acknowledged.", "abstract": "The high efficiency of circular monocoque cylindrical shells in carrying axial loads is impaired by their extreme sensitivity to imperfections and there is an extensive body of literature that addresses this behavior. Instead of following this classical path, focused on circular cross-sections, this paper presents a novel approach that adopts optimal symmetry-breaking wavy cross-sections (wavy shells). The avoidance of imperfection sensitivity is achieved by searching with an evolutionary algorithm for smooth cross-sectional shapes that maximize the minimum among the buckling loads of geometrically perfect and imperfect wavy shells. It is found that shells designed through this approach can achieve higher critical stresses and knockdown factors than any previously known monocoque cylindrical shells. It is also found that these shells have superior mass efficiency to almost all previously reported stiffened shells.", "date": "2015-06-01", "date_type": "published", "publication": "International Journal of Solids and Structures", "volume": "62", "publisher": "Elsevier", "pagerange": "39-51", "id_number": "CaltechAUTHORS:20150604-080335187", "issn": "0020-7683", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150604-080335187", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1016/j.ijsolstr.2014.12.030", "pub_year": "2015", "author_list": "Ning, Xin and Pellegrino, Sergio" }, { "id": "https://authors.library.caltech.edu/records/cg53q-8km52", "eprint_id": 57987, "eprint_status": "archive", "datestamp": "2023-08-20 06:27:28", "lastmod": "2023-10-23 17:58:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wijesekara-W", "name": { "family": "Wijesekara", "given": "Waruna" } }, { "id": "Rosendahl-L", "name": { "family": "Rosendahl", "given": "Lasse" } }, { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Unileg Thermoelectric Generator Design for Oxide Thermoelectrics and Generalization of the Unileg Design Using an Idealized Metal", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Unileg, thermoelectric generator, TEG, thermoelectric, volumetric power density, thermal shorting", "note": "\u00a9 2014 The Minerals, Metals & Materials Society.\n\nReceived July 15, 2014; accepted December 2, 2014; published online December 20, 2014.\n\nW.W. and L.R. gratefully acknowledge the Danish Council for Strategic Research for financial support for the current work through the OTE-Power Project under the Program Commission on Sustainable Energy and Environment (Contract No. 10-093971). G.J.S. and D.R.B. acknowledge the Air Force Office of Science Research MURI FA9550-12-1-0002. D.R.B. acknowledges the support of the Resnick Institute.", "abstract": "The unileg thermoelectric generator (U-TEG) is an increasingly popular concept in the design of thermoelectric generators (TEGs). In this study, an oxide U-TEG design for high-temperature applications is introduced. For the unicouple TEG design, Ca_3Co_4O_9 and Al-doped ZnO are used as the p- and n-leg thermoelectric materials, respectively. For the U-TEG design, constantan and Ca_3Co_4O_9 are employed as conductor and semiconductor, respectively. The reduced current approach (RCA) technique is used to design the unicouple TEG and U-TEG in order to obtain the optimal area ratio. When both the unicouple TEG and U-TEG were subjected to a heat flux of 20 W/cm^2, the volumetric power density was 0.18 W/cm^3 and 0.44 W/cm^3, respectively. Thermal shorting between the hot and cold sides of the generator through the highly thermally conducting conductor, which is one of the major drawbacks of the U-TEG, is overcome by using the optimal area ratio for conductor and semiconductor given by the RCA. The results are further confirmed by finite-element analysis using COMSOL Multiphysics software. Furthermore, the U-TEG design is generalized by using an idealized metal with zero Seebeck coefficient. Even though the idealized metal has no impact on the power output of the U-TEG and all the power in the system is generated by the semiconductor, the U-TEG design succeeded in producing a higher volumetric power density than the unicouple TEG design.", "date": "2015-06", "date_type": "published", "publication": "Journal of Electronic Materials", "volume": "44", "number": "6", "publisher": "Springer", "pagerange": "1834-1845", "id_number": "CaltechAUTHORS:20150603-135324408", "issn": "0361-5235", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150603-135324408", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Danish Council for Strategic Research", "grant_number": "10-093971" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0002" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s11664-014-3569-4", "pub_year": "2015", "author_list": "Wijesekara, Waruna; Rosendahl, Lasse; et al." }, { "id": "https://authors.library.caltech.edu/records/c4vzx-rke73", "eprint_id": 57683, "eprint_status": "archive", "datestamp": "2023-08-20 06:20:11", "lastmod": "2023-10-23 17:38:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laslandes-M", "name": { "family": "Laslandes", "given": "Marie" } }, { "id": "Patterson-K", "name": { "family": "Patterson", "given": "Keith" } }, { "id": "Pellegrino-S", "name": { "family": "Pellegrino", "given": "Sergio" }, "orcid": "0000-0001-9373-3278" } ] }, "title": "Optimized actuators for ultrathin deformable primary mirrors", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Optical Society of America.\n\nReceived 7 January 2015; revised 10 April 2015; accepted 16 April 2015; posted 17 April 2015 (Doc. ID 231885); published 20 May 2015.\n\nDefense Advanced Research Projects Agency (DARPA) (W31P4Q-14-1-0008); National Aeronautics and Space Administration (NASA).\n\nWe thank Xin Ning (Caltech) for help with the optimization algorithm and John Steeves (Caltech) for advice on mirror fabrication. We thank Dr. Harish Manohara (JPL) for providing access to the Microdevices Lab (MDL) cleanroom facilities for sample fabrication. We thank Dr. Risaku Toda (JPL) and Mr. Victor White (JPL) for processing equipment training and usage advice at the MDL. ML acknowledges the support of a postdoctoral grant from the French Defence procurement agency (DGA) held through Aix-Marseille University, France.\nFinancial support from the Keck Institute of Space Studies and\nthe Dow Resnick Bridge program at Caltech is gratefully\nacknowledged. A part of this research was carried out at the\nJet Propulsion Laboratory, California Institute of Technology,\nunder a contract with National Aeronautics and Space\nAdministration (NASA).\n\n

Published - ao-54-15-4937.pdf

", "abstract": "A novel design and selection scheme for surface-parallel actuators for ultrathin, lightweight mirrors is presented. The actuation system consists of electrodes printed on a continuous layer of piezoelectric material bonded to an optical-quality substrate. The electrodes provide almost full coverage of the piezoelectric layer, in order to maximize the amount of active material that is available for actuation, and their shape is optimized to maximize the correctability and stroke of the mirror for a chosen number of independent actuators and for a dominant imperfection mode. The starting point for the design of the electrodes is the observation that the correction of a figure error that has at least two planes of mirror symmetry is optimally done with twin actuators that have the same optimized shape but are rotated through a suitable angle. Additional sets of optimized twin actuators are defined by considering the intersection between the twin actuators, and hence an arbitrarily fine actuation pattern can be generated. It is shown that this approach leads to actuator systems with better performance than simple, geometrically based actuators. Several actuator patterns to correct third-order astigmatism aberrations are presented, and an experimental demonstration of a 41-actuator mirror is also presented.", "date": "2015-05-20", "date_type": "published", "publication": "Applied Optics", "volume": "54", "number": "15", "publisher": "Optical Society of America", "pagerange": "4937-4952", "id_number": "CaltechAUTHORS:20150520-080116235", "issn": "0003-6935", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150520-080116235", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W31P4Q-14-1-0008" }, { "agency": "NASA" }, { "agency": "Minist\u00e8re de la D\u00e9fense, Direction g\u00e9n\u00e9rale de l'armement (DGA)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1364/AO.54.004937", "primary_object": { "basename": "ao-54-15-4937.pdf", "url": "https://authors.library.caltech.edu/records/c4vzx-rke73/files/ao-54-15-4937.pdf" }, "pub_year": "2015", "author_list": "Laslandes, Marie; Patterson, Keith; et al." }, { "id": "https://authors.library.caltech.edu/records/mcby0-pgz14", "eprint_id": 46049, "eprint_status": "archive", "datestamp": "2023-08-20 06:12:41", "lastmod": "2025-04-23 01:09:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brar-Victor-Watson", "name": { "family": "Brar", "given": "Victor W." } }, { "id": "Sherrott-Michelle-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Jang-Min-Seok", "name": { "family": "Jang", "given": "Min Seok" }, "orcid": "0000-0002-5683-1925" }, { "id": "Kim-Seyoon", "name": { "family": "Kim", "given": "Seyoon" }, "orcid": "0000-0002-8040-9521" }, { "id": "Kim-Laura", "name": { "family": "Kim", "given": "Laura" } }, { "id": "Choi-Mansoo", "name": { "family": "Choi", "given": "Mansoo" } }, { "id": "Sweatlock-Luke-A", "name": { "family": "Sweatlock", "given": "Luke A." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Electronic modulation of infrared radiation in graphene plasmonic resonators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Macmillan Publishers Limited. \n\nReceived 14 August 2014; Accepted 26 March 2015; Published 07 May 2015. \n\nThe experimental design, fabrication and characterization of tunable emission structures was supported by the 'Light-Material Interactions in Energy Conversion' Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001293. M.S.J. and M.C. acknowledge support for modelling and simulation from the Global Frontier R&D Program on Center for Multiscale Energy Systems funded by the National Research Foundation under the Ministry of Science, ITC & Future Planning, Korea (2011-0031561, 2014M3A6A7060584). M.C.S. acknowledges support from a Resnick Institute Graduate Fellowship. M.S.J. acknowledges a post-doctoral fellowship from the POSCO TJ Park Foundation. V.W.B. acknowledges support from a Kavli Nanoscience Postdoctoral Fellowship and use of facilities of the Kavli Nanoscience Institute. \n\nContributions: V.W.B., M.C.S.., M.S.J., L.A.S. and H.A.A. conceived the experiment, V.W.B and S.K. fabricated the sample, and V.W.B.and L.A.S. performed measurements and data analysis. M.C.S. performed and analysed FEM simulations. V.W.B. M.C.S., M.S.J. and H.A.A. wrote the paper based on discussions with M.C.\n\n

Published - ncomms8032.pdf

Submitted - 1405.4145.pdf

Supplemental Material - ncomms8032-s1.pdf

", "abstract": "All matter at finite temperatures emits electromagnetic radiation due to the thermally induced motion of particles and quasiparticles. Dynamic control of this radiation could enable the design of novel infrared sources; however, the spectral characteristics of the radiated power are dictated by the electromagnetic energy density and emissivity, which are ordinarily fixed properties of the material and temperature. Here we experimentally demonstrate tunable electronic control of blackbody emission from graphene plasmonic resonators on a silicon nitride substrate. It is shown that the graphene resonators produce antenna-coupled blackbody radiation, which manifests as narrow spectral emission peaks in the mid-infrared. By continuously varying the nanoresonator carrier density, the frequency and intensity of these spectral features can be modulated via an electrostatic gate. This work opens the door for future devices that may control blackbody radiation at timescales beyond the limits of conventional thermo-optic modulation.", "date": "2015-05-07", "date_type": "published", "publication": "Nature Communications", "volume": "6", "number": "5", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 7032", "id_number": "CaltechAUTHORS:20140603-115311871", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140603-115311871", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "National Research Foundation of Korea", "grant_number": "2011-0031561" }, { "agency": "National Research Foundation of Korea", "grant_number": "2014M3A6A7060584" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "POSCO TJ Park Foundation" }, { "agency": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1038/ncomms8032", "primary_object": { "basename": "1405.4145.pdf", "url": "https://authors.library.caltech.edu/records/mcby0-pgz14/files/1405.4145.pdf" }, "related_objects": [ { "basename": "ncomms8032.pdf", "url": "https://authors.library.caltech.edu/records/mcby0-pgz14/files/ncomms8032.pdf" }, { "basename": "ncomms8032-s1.pdf", "url": "https://authors.library.caltech.edu/records/mcby0-pgz14/files/ncomms8032-s1.pdf" } ], "pub_year": "2015", "author_list": "Brar, Victor W.; Sherrott, Michelle C.; et al." }, { "id": "https://authors.library.caltech.edu/records/v22cc-h9t61", "eprint_id": 55406, "eprint_status": "archive", "datestamp": "2023-08-20 05:05:39", "lastmod": "2023-10-20 22:12:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yiyang", "name": { "family": "Liu", "given": "Yiyang" } }, { "id": "Han-Seo-Jung", "name": { "family": "Han", "given": "Seo-Jung" } }, { "id": "Liu-Wen-Bo", "name": { "family": "Liu", "given": "Wen-Bo" }, "orcid": "0000-0003-2687-557X" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Catalytic Enantioselective Construction of Quaternary Stereocenters: Assembly of Key Building Blocks for the Synthesis of Biologically Active Molecules", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: December 29, 2014; Published: February 25, 2015. \n\nThe authors are indebted to the efforts of many members of the Stoltz Research Group whose dedicated efforts produced the chemistry described within this Account. For financial support, we thank NIH-NIGMS (Grant R01GM080269), Amgen, the Gordon and Betty Moore Foundation, Caltech, and the Resnick Sustainability Institute at Caltech (graduate fellowship to Y.L.). S.-J.H. thanks Fulbright (Foreign Student Program, No. 15111120) and the Ilju Foundation of Education & Culture (Predoctoral Research Fellowship) for financial support. Shanghai Institute of Organic Chemistry (SIOC) is thanked for a postdoctoral fellowship to W.-B.L.\n\n

Accepted Version - nihms-1015477.pdf

", "abstract": "The ever-present demand for drugs with better efficacy and fewer side effects continually motivates scientists to explore the vast chemical space. Traditionally, medicinal chemists have focused much attention on achiral or so-called \"flat\" molecules. More recently, attention has shifted toward molecules with stereogenic centers since their three-dimensional structures represent a much larger fraction of the chemical space and have a number of superior properties compared with flat aromatic compounds. Quaternary stereocenters, in particular, add greatly to the three-dimensionality and novelty of the molecule. Nevertheless, synthetic challenges in building quaternary stereocenters have largely prevented their implementation in drug discovery. The lack of effective and broadly general methods for enantioselective formation of quaternary stereocenters in simple molecular scaffolds has prompted us to investigate new chemistry and develop innovative tools and solutions.\n\nIn this Account, we describe three approaches to constructing quaternary stereocenters: nucleophilic substitution of 3-halooxindoles, conjugate addition of boronic acids to cyclic enones, and allylic alkylation of enolates. In the first approach, malonic ester nucleophiles attack electrophilic 3-halooxindoles, mediated by a copper(II)-bisoxazoline catalyst. A variety of oxindoles containing a benzylic quaternary stereocenter can be accessed through this method. However, it is only applicable to the specialized 3,3-disubstituted oxindole system. To access benzylic quaternary stereocenters in a more general context, we turned our attention to the enantioselective conjugate addition of carbon nucleophiles to \u03b1,\u03b2-unsaturated carbonyl acceptors. We discovered that in the presence of catalytic palladium-pyridinooxazoline complex, arylboronic acids add smoothly to \u03b2-substituted cyclic enones to furnish ketones with a \u03b2-benzylic quaternary stereocenter in high yields and enantioselectivities. The reaction is compatible with a wide range of arylboronic acids, \u03b2-substituents, and ring sizes.\n\nAside from benzylic quaternary stereocenters, a more challenging motif is a quaternary stereocenter not adjacent to an aromatic group. Such centers represent more general structures in chemical space but are more difficult to form by asymmetric catalysis. To address this greater challenge, and motivated by the greater reward, we entered the field of palladium-catalyzed asymmetric allylic alkylation of prochiral enolate nucleophiles about a decade ago. On the basis of Tsuji's work, which solved the issue of positional selectivity for unsymmetrical ketones, we discovered that the phosphinooxazoline ligand effectively rendered this reaction enantioselective. Extensive investigations since then have revealed that the reaction exhibits broad scope and accepts a range of substrate classes, each with its unique advantage in synthetic applications. A diverse array of carbonyl compounds bearing \u03b1-quaternary stereocenters are obtained in excellent yields and enantioselectivities, and more possibilities have yet to be explored. As an alternative to palladium catalysis, we also studied iridium-catalyzed asymmetric allylic alkylations that generate vicinal quaternary and tertiary stereocenters in a single transformation. Overall, these methods provide access to small molecule building blocks with a single quaternary stereocenter, can be applied to various molecular scaffolds, and tolerate a wide range of functional groups. We envision that the chemistry reported in this Account will be increasingly useful in drug discovery and design.", "date": "2015-03", "date_type": "published", "publication": "Accounts of Chemical Research", "volume": "48", "number": "3", "publisher": "American Chemical Society", "pagerange": "740-751", "id_number": "CaltechAUTHORS:20150302-110204535", "issn": "0001-4842", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150302-110204535", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01GM080269-01" }, { "agency": "Amgen" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Caltech" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Fulbright Foundation", "grant_number": "15111120" }, { "agency": "Ilju Foundation of Education & Culture" }, { "agency": "Shanghai Institute of Organic Chemistry (SIOC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/ar5004658", "pmcid": "PMC6410712", "primary_object": { "basename": "nihms-1015477.pdf", "url": "https://authors.library.caltech.edu/records/v22cc-h9t61/files/nihms-1015477.pdf" }, "pub_year": "2015", "author_list": "Liu, Yiyang; Han, Seo-Jung; et al." }, { "id": "https://authors.library.caltech.edu/records/cm86v-dwe23", "eprint_id": 53561, "eprint_status": "archive", "datestamp": "2023-08-20 05:04:35", "lastmod": "2024-03-05 17:05:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bose-Subhonmesh", "name": { "family": "Bose", "given": "Subhonmesh" }, "orcid": "0000-0002-3445-4479" }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "Teeraratkul-T", "name": { "family": "Teeraratkul", "given": "Thanchanok" } }, { "id": "Hassibi-B", "name": { "family": "Hassibi", "given": "Babak" }, "orcid": "0000-0002-1375-5838" } ] }, "title": "Equivalent relaxations of optimal power flow", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 IEEE.\n\nReceived: September 7, 2014.\n\nWe are thankful to Prof. K. Mani Chandy and Lingwen Gan at Caltech for helpful discussions. We also acknowledge the support of NSF through NetSE grant CNS 0911041, CNS-0932428, CCF-1018927, CCF-1423663 and CCF-1409204, ARPA-E through grant DE-AR0000226, the National Science Council of Taiwan (R. O. C.) through grant NSC 103-3113-P-008-001, Southern California Edison, the Los Alamos National Lab (DoE), Resnick Institute at Caltech, Office of Naval Research under the MURI grant N00014-08\u20130747, Qualcomm Inc., and King Abdulaziz University.\n\n

Submitted - Equivalent_20relaxations_20of_20optimal_20power_20flow.pdf

", "abstract": "Several convex relaxations of the optimal power flow (OPF) problem have recently been developed using both bus injection models and branch flow models. In this paper, we prove relations among three convex relaxations: a semidefinite relaxation that computes a full matrix, a chordal relaxation based on a chordal extension of the network graph, and a second-order cone relaxation that computes the smallest partial matrix. We prove a bijection between the feasible sets of the OPF in the bus injection model and the branch flow model, establishing the equivalence of these two models and their second-order cone relaxations. Our results imply that, for radial networks, all these relaxations are equivalent and one should always solve the second-order cone relaxation. For mesh networks, the semidefinite relaxation and the chordal relaxation are equally tight and both are strictly tighter than the second-order cone relaxation. Therefore, for mesh networks, one should either solve the chordal relaxation or the SOCP relaxation, trading off tightness and the required computational effort. Simulations are used to illustrate these results.", "date": "2015-03", "date_type": "published", "publication": "IEEE Transactions on Automatic Control", "volume": "60", "number": "3", "publisher": "IEEE", "pagerange": "729-742", "id_number": "CaltechAUTHORS:20150112-101936328", "issn": "0018-9286", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150112-101936328", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS 0911041" }, { "agency": "NSF", "grant_number": "CNS-0932428" }, { "agency": "NSF", "grant_number": "CCF-1018927" }, { "agency": "NSF", "grant_number": "CCF-1423663" }, { "agency": "NSF", "grant_number": "CCF-1409204" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "National Science Council of Taiwan", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Southern California Edison" }, { "agency": "Los Alamos National Laboratory (LANL)" }, { "agency": "Caltech Resnick Institute" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-08-0747" }, { "agency": "Qualcomm Inc." }, { "agency": "King Abdulaziz University" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TAC.2014.2357112", "primary_object": { "basename": "Equivalent_20relaxations_20of_20optimal_20power_20flow.pdf", "url": "https://authors.library.caltech.edu/records/cm86v-dwe23/files/Equivalent_20relaxations_20of_20optimal_20power_20flow.pdf" }, "pub_year": "2015", "author_list": "Bose, Subhonmesh; Low, Steven H.; et al." }, { "id": "https://authors.library.caltech.edu/records/ft6sa-gk325", "eprint_id": 54285, "eprint_status": "archive", "datestamp": "2023-08-22 14:58:29", "lastmod": "2023-10-20 15:46:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "McDowell-M-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Nielander-A-C", "name": { "family": "Nielander", "given": "Adam C." }, "orcid": "0000-0002-3639-2427" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Yang-Fan", "name": { "family": "Yang", "given": "Fan" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Stable Solar-Driven Water Oxidation to O_2(g) by Ni-Oxide-Coated Silicon Photoanodes", "ispublished": "pub", "full_text_status": "public", "keywords": "semiconductors; photoanodes; solar-fuels; water-splitting", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: December 11, 2014; accepted: January 19.\n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DESC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. UV\u2212vis spectroscopy and atomic-force microscopy were performed at the Molecular Materials Research Center (MMRC) in the Beckman Institute at the California Institute of Technology. B.S.B. was supported by the Beckman Institute of the California Institute of Technology. A.C.N. was supported by a Graduate Research Fellowship from the National Science Foundation. M.R.S. was supported by a graduate fellowship from the Resnick Sustainability Institute. This work was additionally supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. We thank K. Walczak for providing the FTO coated np+-Si(100) samples, C. Koval, R. Liu, and M. Lichterman for stimulating discussions, N. Becerra and L. Zhou for their assistance with XRD measurements, and K. Papadantonakis for assistance with editing this manuscript.\n\n

Supplemental Material - jz5026195_si_001.pdf

", "abstract": "Semiconductors with small band gaps (<2 eV) must be stabilized against corrosion or passivation in aqueous electrolytes before such materials can be used as photoelectrodes to directly produce fuels from sunlight. In addition, incorporation of electrocatalysts on the surface of photoelectrodes is required for efficient oxidation of H_2O to O_2(g) and reduction of H_2O or H_2O and CO_2 to fuels. We report herein the stabilization of np^+-Si(100) and n-Si(111) photoanodes for over 1200 h of continuous light-driven evolution of O_2(g) in 1.0 M KOH(aq) by an earth-abundant, optically transparent, electrocatalytic, stable, conducting nickel oxide layer. Under simulated solar illumination and with optimized index-matching for proper antireflection, NiO_x-coated np+-Si(100) photoanodes produced photocurrent-onset potentials of \u2212180 \u00b1 20 mV referenced to the equilibrium potential for evolution of O_2(g), photocurrent densities of 29 \u00b1 1.8 mA cm^(\u20132) at the equilibrium potential for evolution of O_2(g), and a solar-to-O_2(g) conversion figure-of-merit of 2.1%.", "date": "2015-02-19", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "6", "number": "4", "publisher": "American Chemical Society", "pagerange": "592-598", "id_number": "CaltechAUTHORS:20150202-095259720", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150202-095259720", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" }, { "agency": "NSF" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/jz5026195", "primary_object": { "basename": "jz5026195_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ft6sa-gk325/files/jz5026195_si_001.pdf" }, "pub_year": "2015", "author_list": "Sun, Ke; McDowell, Matthew T.; et al." }, { "id": "https://authors.library.caltech.edu/records/cvfqr-6b645", "eprint_id": 51898, "eprint_status": "archive", "datestamp": "2023-08-20 04:53:24", "lastmod": "2023-10-18 18:40:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toutov-A-A", "name": { "family": "Toutov", "given": "Anton A." }, "orcid": "0000-0002-6561-0462" }, { "id": "Liu-Wen-Bo", "name": { "family": "Liu", "given": "Wen-Bo" }, "orcid": "0000-0003-2687-557X" }, { "id": "Betz-K-N", "name": { "family": "Betz", "given": "Kerry N." }, "orcid": "0000-0001-9118-5909" }, { "id": "Fedorov-Alexey", "name": { "family": "Fedorov", "given": "Alexey" }, "orcid": "0000-0001-9814-6726" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Silylation of C\u2013H bonds in aromatic heterocycles by an Earth-abundant metal catalyst", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Macmillan Publishers.\n\nThese authors contributed equally to this work.\n\nReceived 15 August; accepted 27 November 2014.\n\nThis work was supported by the NSF under the CCI Center for\nSelective C\u2013H Functionalization(CHE-1205646) and under CHE-1212767, and by BP under the XC^2 initiative. We thank the Novartis Institutes for Biomedical Research\nIncorporated for the donation of samples to the CCHF. D. Morton is thanked for a donation of thenalidine. A.A.T. is grateful to the Resnick Sustainability Institute at\nCaltech and to Dow Chemical for a predoctoral fellowship, and to NSERC for a PGS D fellowship. The Shanghai Institute of Organic Chemistry (SIOC) and S.-L. You are\nthanked for a postdoctoral fellowship to W.-B.L. We thank S. Virgil and the Caltech Center for Catalysis and Chemical Synthesis for access to analytical equipment. D.Vandervelde is acknowledged for assistance with NMR interpretation. N. Dalleska is thanked for assistance with ICP-MS trace metal analysis. M. Shahgoli and N. Torian are\nacknowledged for assistance with high-resolution mass spectrometry.\n\nA.A.T., W.-B.L. and K.N.B. developed the reactions, performed the experiments and analysed data. A.F. analysed data. A.A.T and R.H.G. had the idea for and directed the investigations with W.-B.L. and B.M.S. A.A.T. and W.-B.L. prepared the manuscript with contributions from all authors. All authors contributed to discussions.\n\n

Supplemental Material - nature14126-s1.pdf

", "abstract": "Heteroaromatic compounds containing carbon\u2013silicon (C\u2013Si) bonds are of great interest in the fields of organic electronics and photonics1, drug discovery, nuclear medicine and complex molecule synthesis, because these compounds have very useful physicochemical properties. Many of the methods now used to construct heteroaromatic C\u2013Si bonds involve stoichiometric reactions between heteroaryl organometallic species and silicon electrophiles or direct, transition-metal-catalysed intermolecular carbon\u2013hydrogen (C\u2013H) silylation using rhodium or iridium complexes in the presence of excess hydrogen acceptors. Both approaches are useful, but their limitations include functional group incompatibility, narrow scope of application, high cost and low availability of the catalysts, and unproven scalability. For this reason, a new and general catalytic approach to heteroaromatic C\u2013Si bond construction that avoids such limitations is highly desirable. Here we report an example of cross-dehydrogenative heteroaromatic C\u2013H functionalization catalysed by an Earth-abundant alkali metal species. We found that readily available and inexpensive potassium tert-butoxide catalyses the direct silylation of aromatic heterocycles with hydrosilanes, furnishing heteroarylsilanes in a single step. The silylation proceeds under mild conditions, in the absence of hydrogen acceptors, ligands or additives, and is scalable to greater than 100 grams under optionally solvent-free conditions. Substrate classes that are difficult to activate with precious metal catalysts are silylated in good yield and with excellent regioselectivity. The derived heteroarylsilane products readily engage in versatile transformations enabling new synthetic strategies for heteroaromatic elaboration, and are useful in their own right in pharmaceutical and materials science applications.", "date": "2015-02-05", "date_type": "published", "publication": "Nature", "volume": "518", "number": "7537", "publisher": "Nature Publishing Group", "pagerange": "80-84", "id_number": "CaltechAUTHORS:20141118-102135823", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141118-102135823", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1205646" }, { "agency": "NSF", "grant_number": "CHE-1212767" }, { "agency": "BP XC2 Program" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Shanghai Institute of Organic Chemistry (SIOC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/nature14126", "primary_object": { "basename": "nature14126-s1.pdf", "url": "https://authors.library.caltech.edu/records/cvfqr-6b645/files/nature14126-s1.pdf" }, "pub_year": "2015", "author_list": "Toutov, Anton A.; Liu, Wen-Bo; et al." }, { "id": "https://authors.library.caltech.edu/records/3w0n1-6vt55", "eprint_id": 53190, "eprint_status": "archive", "datestamp": "2023-08-20 04:43:39", "lastmod": "2023-10-19 14:38:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thoi-V-Sara", "name": { "family": "Thoi", "given": "V. Sara" } }, { "id": "Usiskin-Robert-E", "name": { "family": "Usiskin", "given": "Robert E." } }, { "id": "Haile-S-M", "name": { "family": "Haile", "given": "Sossina M." }, "orcid": "0000-0002-5293-6252" } ] }, "title": "Platinum-decorated carbon nanotubes for hydrogen oxidation and proton reduction in solid acid electrochemical cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. \n\nReceived 30 Sep 2014, Accepted 10 Dec 2014, First published online 22 Dec 2014. \n\nThis work was supported by the Dow-Bridge Program through\nthe Resnick Sustainability Institute at Caltech, as well as by a\nResnick Graduate Student Fellowship (R.E.U.). We thank Dr\nTim Davenport, Michael Ignatowich, and Webster Guan for\ntheir assistance in TGA measurements, and Nate Thomas and\nAnupama Khan for their assistance in imaging. We also\nacknowledge Prof. George R. Rossman for his assistance with\nRaman Spectroscopy, Ben Myers from Northwestern University's Atomic and Nanoscale Characterization Experimental Center (NUANCE) for SEM imaging (Fig. 2). In addition, we acknowledge Caltech's Kavli Nanoscience Institute (KNI) for access to additional imaging instrumentation and the Molecular Materials Research Center at Caltech for the use of the Cahn C-35 Ultra-Microbalance.\n\n

Published - c4sc03003f.pdf

Supplemental Material - c4sc03003f1.pdf

", "abstract": "Pt-decorated carbon nanotubes (Pt-CNTs) were used to enhance proton reduction and hydrogen evolution in solid acid electrochemical cells based on the proton-conducting electrolyte CsH_2PO_4. The carbon nanotubes served as interconnects to the current collector and as a platform for interaction between the Pt and CsH_2PO_4, ensuring minimal catalyst isolation and a large number density of active sites. Particle size matching was achieved by using electrospray deposition to form sub-micron to nanometric CsH_2PO_4. A porous composite electrode was fabricated from electrospray deposition of a solution of Pt-CNTs and CsH_2PO_4. Using AC impedance spectroscopy and cyclic voltammetry, the total electrode overpotential corresponding to proton reduction and hydrogen oxidation of the most active electrodes containing just 0.014 mg cm^(\u22121) of Pt was found to be 0.1 V (or 0.05 V per electrode) at a current density of 42 mA cm^(\u22122) for a measurement temperature of 240 \u00b0C and a hydrogen-steam atmosphere. The zero bias electrode impedance was 1.2 \u03a9 cm2, corresponding to a Pt utilization of 61 S mg^(\u22121), a 3-fold improvement over state-of-the-art electrodes with a 50\u00d7 decrease in Pt loading.", "date": "2015-02", "date_type": "published", "publication": "Chemical Science", "volume": "6", "number": "2", "publisher": "Royal Society of Chemistry", "pagerange": "1570-1577", "id_number": "CaltechAUTHORS:20150105-134450527", "issn": "2041-6520", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150105-134450527", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow-Bridge Program" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/c4sc03003f", "pmcid": "PMC5811139", "primary_object": { "basename": "c4sc03003f1.pdf", "url": "https://authors.library.caltech.edu/records/3w0n1-6vt55/files/c4sc03003f1.pdf" }, "related_objects": [ { "basename": "c4sc03003f.pdf", "url": "https://authors.library.caltech.edu/records/3w0n1-6vt55/files/c4sc03003f.pdf" } ], "pub_year": "2015", "author_list": "Thoi, V. Sara; Usiskin, Robert E.; et al." }, { "id": "https://authors.library.caltech.edu/records/9a68d-ja779", "eprint_id": 55290, "eprint_status": "archive", "datestamp": "2023-08-22 14:50:02", "lastmod": "2023-10-20 22:04:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Duvvuri-S", "name": { "family": "Duvvuri", "given": "Subrahmanyam" }, "orcid": "0000-0001-8082-1658" }, { "id": "McKeon-B-J", "name": { "family": "McKeon", "given": "Beverley J." }, "orcid": "0000-0003-4220-1583" } ] }, "title": "Triadic scale interactions in a turbulent boundary layer", "ispublished": "pub", "full_text_status": "restricted", "keywords": "turbulent boundary layers; skewness; amplitude modulation coefficient; triadic scale interactions; synthetic large-scale; phase-organization", "note": "\u00a9 2015 Cambridge University Press.\n\nReceived 11 December 2014; revised 26 January 2015; accepted 3 February 2015.\n\nThe authors gratefully acknowledge AFOSR (grant FA 9550-12-1-0469, program manager D. Smith) for the financial support of this work, and a graduate fellowship (S.D.) from the Resnick Institute at Caltech. We are grateful to K. Rosenberg for help with the wind tunnel set-up, and to R. Moarref and M. Luhar for many stimulating\nresearch discussions.", "abstract": "A formal relationship between the skewness and the correlation coefficient of large and small scales, termed the amplitude modulation coefficient, is established for a\ngeneral statistically stationary signal and is analysed in the context of a turbulent velocity signal. Both the quantities are seen to be measures of phase in triadically\nconsistent interactions between scales of turbulence. The naturally existing phase relationships between large and small scales in a turbulent boundary layer are then\nmanipulated by exciting a synthetic large-scale motion in the flow using a spatially\nimpulsive dynamic wall roughness perturbation. The synthetic scale is seen to alter\nthe phase relationships, or the degree of modulation, in a quasi-deterministic manner by exhibiting a phase-organizing influence on the small scales. The results presented provide encouragement for the development of a practical framework for favourable manipulation of energetic small-scale turbulence through large-scale inputs in a wall-bounded turbulent flow.", "date": "2015-02", "date_type": "published", "publication": "Journal of Fluid Mechanics", "volume": "767", "publisher": "Cambridge University Press", "pagerange": "R4", "id_number": "CaltechAUTHORS:20150227-022811215", "issn": "0022-1120", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150227-022811215", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA 9550-12-1-0469" }, { "agency": "Resnick Institute Graduate Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "GALCIT" } ] }, "doi": "10.1017/jfm.2015.79", "pub_year": "2015", "author_list": "Duvvuri, Subrahmanyam and McKeon, Beverley J." }, { "id": "https://authors.library.caltech.edu/records/c63sw-pdv64", "eprint_id": 50252, "eprint_status": "archive", "datestamp": "2023-08-20 04:29:31", "lastmod": "2023-10-17 22:52:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nielander-A-C", "name": { "family": "Nielander", "given": "Adam C." }, "orcid": "0000-0002-3639-2427" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A taxonomy for solar fuels generators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 18 Jul 2014, Accepted 19 Sep 2014,\nFirst published online 19 Sep 2014.\n\nACN acknowledges the NSF, Grant CHE-1214152, and the National Science Foundation Graduate Research Fellowship for support. KMP acknowledges support from the DOE, Grant DEFG02-03ER15483. MRS acknowledges the Resnick Sustainability\nInstitute for a graduate fellowship. This material is based upon\nwork performed by the Joint Center for Artificial Photosynthesis,\na DOE Energy Innovation Hub, supported through the\nOffice of Science of the U.S. Department of Energy under Award\nNumber DE-SC0004993.\n\n

Published - c4ee02251c.pdf

", "abstract": "A number of approaches to solar fuels generation are being developed, each of which has associated\nadvantages and challenges. Many of these solar fuels generators are identified as \"photoelectrochemical\ncells\" even though these systems collectively operate based on a suite of fundamentally different\nphysical principles. To facilitate appropriate comparisons between solar fuels generators, as well as to\nenable concise and consistent identification of the state-of-the-art for designs based on comparable\noperating principles, we have developed a taxonomy and nomenclature for solar fuels generators based\non the source of the asymmetry that separates photogenerated electrons and holes. Three basic device\ntypes have been identified: photovoltaic cells, photoelectrochemical cells, and particulate/molecular\nphotocatalysts. We outline the advantages and technological challenges associated with each type, and\nprovide illustrative examples for each approach as well as for hybrid approaches.", "date": "2015-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "16-25", "id_number": "CaltechAUTHORS:20141008-080542214", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141008-080542214", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c4ee02251c", "primary_object": { "basename": "c4ee02251c.pdf", "url": "https://authors.library.caltech.edu/records/c63sw-pdv64/files/c4ee02251c.pdf" }, "pub_year": "2015", "author_list": "Nielander, Adam C.; Shaner, Matthew R.; et al." }, { "id": "https://authors.library.caltech.edu/records/rc4xp-yqj60", "eprint_id": 51816, "eprint_status": "archive", "datestamp": "2023-08-20 04:29:37", "lastmod": "2023-10-18 17:57:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-Matthew-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Stabilization of Si microwire arrays for solar-driven H\u2082O oxidation to O\u2082(g) in 1.0 M KOH(aq) using conformal coatings of amorphous TiO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 22 Sep 2014, Accepted 29 Oct 2014,\nFirst published online 05 Nov 2014.\n\nThe authors would like to acknowledge Dr Ragip Pala for assistance with the spectral response measurement system. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. M. R. S. is supported by a graduate fellowship from the Resnick Institute for Sustainability. The authors also acknowledge support from the Gordon and Betty Moore Foundation.\n\n

Published - c4ee03012e.pdf

Supplemental Material - c4ee03012e1.pdf

", "abstract": "Conductive, amorphous TiO\u2082 coatings deposited by atomic-layer deposition, in combination with a sputter deposited NiCrO\u2093 oxygen-evolution catalyst, have been used to protect Si microwire arrays from passivation or corrosion in contact with aqueous electrolytes. Coated np\u207a-Si/TiO\u2082/NiCrO\u2093 as well as heterojunction n-Si/TiO\u2082/NiCrO\u2093 Si microwire-array photoanodes exhibited stable photoelectrochemical operation in aqueous ferri-/ferro-cyanide solutions. The coatings also allowed for photoanodic water oxidation in 1.0 M KOH(aq) solutions for >2200 h of continuous operation under simulated 1 Sun conditions with 100% Faradaic efficiency for the evolution of O\u2082(g).", "date": "2015-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "203-207", "id_number": "CaltechAUTHORS:20141117-083607403", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141117-083607403", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c4ee03012e", "primary_object": { "basename": "c4ee03012e1.pdf", "url": "https://authors.library.caltech.edu/records/rc4xp-yqj60/files/c4ee03012e1.pdf" }, "related_objects": [ { "basename": "c4ee03012e.pdf", "url": "https://authors.library.caltech.edu/records/rc4xp-yqj60/files/c4ee03012e.pdf" } ], "pub_year": "2015", "author_list": "Shaner, Matthew R.; Hu, Shu; et al." }, { "id": "https://authors.library.caltech.edu/records/7byye-f8609", "eprint_id": 54315, "eprint_status": "archive", "datestamp": "2023-08-20 04:20:58", "lastmod": "2023-10-20 15:48:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gan-Lingwen", "name": { "family": "Gan", "given": "Lingwen" } }, { "id": "Li-Na", "name": { "family": "Li", "given": "Na" } }, { "id": "Topcu-U", "name": { "family": "Topcu", "given": "Ufuk" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Exact Convex Relaxation of Optimal Power Flow in Radial Networks", "ispublished": "pub", "full_text_status": "public", "keywords": "Optimal power flow (OPF)", "note": "\u00a9 2014 IEEE. \n\nManuscript received March 20, 2013; revised November 19, 2013, March 13, 2014, and May 26, 2014; accepted May 27, 2014. Date of publication June 25, 2014; date of current version December 22, 2014. \n\nThis work was supported by NSF NetSE grant CNS 0911041, ARPA-E grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan, grant NSC 103-3113-P-008-001, Los Alamos National Lab through a DoE grant, Resnick Institute, and AFOSR award FA9550-12-1-0302. Recommended by Associate Editor C. M. Lagoa.\n\n

Submitted - 1311.7170.pdf

", "abstract": "The optimal power flow (OPF) problem determines a network operating point that minimizes a certain objective such as generation cost or power loss. It is nonconvex. We prove that a global optimum of OPF can be obtained by solving a second-order cone program, under a mild condition after shrinking the OPF feasible set slightly, for radial power networks. The condition can be checked a priori, and holds for the IEEE 13, 34, 37, 123-bus networks and two real-world networks.", "date": "2015-01", "date_type": "published", "publication": "IEEE Transactions on Automatic Control", "volume": "60", "number": "1", "publisher": "IEEE", "pagerange": "72-87", "id_number": "CaltechAUTHORS:20150203-084513340", "issn": "0018-9286", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150203-084513340", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0911041" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Los Alamos National Lab" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0302" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TAC.2014.2332712", "primary_object": { "basename": "1311.7170.pdf", "url": "https://authors.library.caltech.edu/records/7byye-f8609/files/1311.7170.pdf" }, "pub_year": "2015", "author_list": "Gan, Lingwen; Li, Na; et al." }, { "id": "https://authors.library.caltech.edu/records/5jzwq-mae13", "eprint_id": 53450, "eprint_status": "archive", "datestamp": "2023-08-20 04:20:03", "lastmod": "2025-04-23 01:11:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kosten-E-D", "name": { "family": "Kosten", "given": "Emily D." } }, { "id": "Newman-B-K", "name": { "family": "Newman", "given": "Bonna K." } }, { "id": "Lloyd-J-V", "name": { "family": "Lloyd", "given": "John V." } }, { "id": "Polman-A", "name": { "family": "Polman", "given": "Albert" }, "orcid": "0000-0002-0685-3886" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Limiting Light Escape Angle in Silicon Photovoltaics: Ideal and Realistic Cells", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Nanostructures, photovoltaic cells, silicon", "note": "\u00a9 2014 IEEE.\n\nManuscript received June 29, 2014; revised September 11, 2014; accepted\nSeptember 17, 2014. Date of publication October 22, 2014; date of current\nversion December 18, 2014. \n\nThe work of E. D. Kosten and H. A. Atwater was\nsupported by the Light\u2013Matter Interactions Energy Frontier Research Center: an\nEFRC program of the Office of Science, United States Department of Energy,\nunder Grant DE-SC0001293. The work of E. D. Kosten was supported by\nthe Resnick Sustainability Institute Graduate Fellowship. The work of J. V.\nLloyd was supported by the DOW Chemical Company. Work at the Center for\nNanophotonics at AMOLF is part of the research program of FOM, which is\nfinancially supported by NWO. It is also supported by the European Research\nCouncil. E. D. Kosten and B. K. Newman contributed equally to this work.\n\nThe authors would like to thank M. Sheldon, H. Emmer,\nand W. Sinke for insightful discussions and advice on the\nmanuscript.", "abstract": "Restricting the light escape angle within a solar cell significantly enhances light trapping, resulting in potentially higher efficiency in thinner cells. Using an improved detailed balance model for silicon and neglecting diffuse light, we calculate an efficiency gain of 3%_(abs) for an ideal Si cell of 3-\u00b5m thickness and the escape angle restricted to 2.767\u00b0 under AM1.5 direct illumination. Applying the model to current high-efficiency cell technologies, we find that a heterojunction-type device with better surface and contact passivation is better suited to escape angle restriction than a homojunction type device. In these more realistic cell models, we also find that there is little benefit gained by restricting the escape angle to less than 10\u00b0. The benefits of combining moderate escape angle restriction with low to moderate concentration offers further efficiency gains. Finally, we consider two potential structures for escape angle restriction: a narrowband graded index optical multilayer and a broadband ray optical structure. The broadband structure, which provides greater angle restriction, allows for higher efficiencies and much thinner cells than the narrowband structure.", "date": "2015-01", "date_type": "published", "publication": "IEEE Journal of Photovoltaics", "volume": "5", "number": "1", "publisher": "IEEE", "pagerange": "61-69", "id_number": "CaltechAUTHORS:20150109-081928470", "issn": "2156-3381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150109-081928470", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" }, { "agency": "European Research Council (ERC)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/JPHOTOV.2014.2360566", "pub_year": "2015", "author_list": "Kosten, Emily D.; Newman, Bonna K.; et al." }, { "id": "https://authors.library.caltech.edu/records/aqd0d-syb19", "eprint_id": 53056, "eprint_status": "archive", "datestamp": "2023-08-20 04:02:44", "lastmod": "2025-04-23 01:09:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Jermyn-A-S", "name": { "family": "Jermyn", "given": "Adam S." }, "orcid": "0000-0001-5048-9973" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Theoretical predictions for hot-carrier generation from surface plasmon decay", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Macmillan Publishers Limited. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ \n\nReceived 03 September 2014. Accepted 07 November 2014. Published 16 December 2014. \n\nWe thank Marco Bernardi for detailed feedback on and suggestions towards improving this manuscript; Tonatiuh Rangel, Jamal Mustafa and Marco Bernardi for private communications of noble metal GW band structures; and Yuan Ping for useful discussions. This material is based on the work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute.\n\n

Published - ncomms6788.pdf

", "abstract": "Decay of surface plasmons to hot carriers finds a wide variety of applications in energy conversion, photocatalysis and photodetection. However, a detailed theoretical description of plasmonic hot-carrier generation in real materials has remained incomplete. Here we report predictions for the prompt distributions of excited 'hot' electrons and holes generated by plasmon decay, before inelastic relaxation, using a quantized plasmon model with detailed electronic structure. We find that carrier energy distributions are sensitive to the electronic band structure of the metal: gold and copper produce holes hotter than electrons by 1\u20132\u2009eV, while silver and aluminium distribute energies more equitably between electrons and holes. Momentum-direction distributions for hot carriers are anisotropic, dominated by the plasmon polarization for aluminium and by the crystal orientation for noble metals. We show that in thin metallic films intraband transitions can alter the carrier distributions, producing hotter electrons in gold, but interband transitions remain dominant.", "date": "2014-12-16", "date_type": "published", "publication": "Nature Communications", "volume": "5", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 5788", "id_number": "CaltechAUTHORS:20141219-150047470", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141219-150047470", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "1099", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1038/ncomms6788", "pmcid": "PMC4284641", "primary_object": { "basename": "ncomms6788.pdf", "url": "https://authors.library.caltech.edu/records/aqd0d-syb19/files/ncomms6788.pdf" }, "pub_year": "2014", "author_list": "Sundararaman, Ravishankar; Narang, Prineha; et al." }, { "id": "https://authors.library.caltech.edu/records/a3sqk-6yh94", "eprint_id": 52221, "eprint_status": "archive", "datestamp": "2023-08-20 04:01:53", "lastmod": "2023-10-18 19:40:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laga-S-M", "name": { "family": "Laga", "given": "Stephanie M." } }, { "id": "Blakemore-J-D", "name": { "family": "Blakemore", "given": "James D." }, "orcid": "0000-0003-4172-7460" }, { "id": "Henling-L-M", "name": { "family": "Henling", "given": "Lawrence M." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Catalysis of Proton Reduction by a [BO_4]-Bridged Dicobalt Glyoxime", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society.\n\nReceived: July 28, 2014; published: November 19, 2014.\n\nThe authors thank Ivonne Ferrer for helpful discussions and\nAaron Sattler for assistance in preparation of Figure 2. This research was carried out in part at the Molecular Materials Research Center of the Beckman Institute at Caltech. The research was supported by the Resnick Sustainability Institute at Caltech (Postdoctoral Fellowship to J.D.B.) and the NSF CCI Solar Fuels Program (CHE-1305124 and a CCI Postdoctoral Fellowship to J.D.B.). The Bruker KAPPA APEXII X-ray diffractometer was purchased via an NSF CRIF:MU award to the California Institute of Technology (CHE-0639094). Gas chromatographs were collected at the Joint Center for Artificial Photosynthesis at Caltech.\n\n

Supplemental Material - ic501804h_si_001.pdf

Supplemental Material - ic501804h_si_002.cif

", "abstract": "We report the preparation of a dicobalt compound with two singly proton-bridged cobaloxime units linked by a central [BO_4] bridge. Reaction of a doubly proton-bridged cobaloxime complex with trimethyl borate afforded the compound in good yield. Single-crystal X-ray diffraction studies confirmed the bridging nature of the [BO_4] moiety. Using electrochemical methods, the dicobalt complex was found to be an electrocatalyst for proton reduction in acetonitrile solution. Notably, the overpotential for proton reduction (954 mV) was found to be higher than in the cases of two analogous single-site cobalt glyoximes under virtually identical conditions.", "date": "2014-12-15", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "53", "number": "24", "publisher": "American Chemical Society", "pagerange": "12668-12670", "id_number": "CaltechAUTHORS:20141201-105741726", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141201-105741726", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "NSF Postdoctoral Fellowship" }, { "agency": "NSF", "grant_number": "CHE-0639094" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" }, { "id": "JCAP" } ] }, "doi": "10.1021/ic501804h", "primary_object": { "basename": "ic501804h_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a3sqk-6yh94/files/ic501804h_si_001.pdf" }, "related_objects": [ { "basename": "ic501804h_si_002.cif", "url": "https://authors.library.caltech.edu/records/a3sqk-6yh94/files/ic501804h_si_002.cif" } ], "pub_year": "2014", "author_list": "Laga, Stephanie M.; Blakemore, James D.; et al." }, { "id": "https://authors.library.caltech.edu/records/zpqnb-ywg43", "eprint_id": 49116, "eprint_status": "archive", "datestamp": "2023-08-20 03:29:12", "lastmod": "2023-10-17 21:08:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brinkmann-Chen-S", "name": { "family": "Brinkmann-Chen", "given": "S." }, "orcid": "0000-0002-5419-4192" }, { "id": "Cahn-J-K-B", "name": { "family": "Cahn", "given": "J. K. B." } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Uncovering rare NADH-preferring ketol-acid reductoisomerases", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Elsevier B.V.\n\nReceived 20 June 2014, Revised 1 August 2014, Accepted 19 August 2014, Available online 27 August 2014.\n\nJ.K.B.C. acknowledges the support of the Resnick Sustainability Institute (Caltech). This publication is funded by the Gordon and Betty Moore Foundation through Grant GBMF2809 to the Caltech Programmable Molecular Technology Initiative. \n\nAuthor contributions: SBC, JKBC, and FHA designed research. SBC and JKBC performed research and analyzed data. SBC, JKBC, and FHA wrote the paper.\n\n

Accepted Version - JACKSON-1-s2.0-S1096717614001062-main.pdf

Supplemental Material - mmc1.doc

Supplemental Material - mmc2.doc

", "abstract": "All members of the ketol-acid reductoisomerase (KARI) enzyme family characterized to date have been shown to prefer the nicotinamide adenine dinucleotide phosphate hydride (NADPH) cofactor to nicotinamide adenine dinucleotide hydride (NADH). However, KARIs with the reversed cofactor preference are desirable for industrial applications, including anaerobic fermentation to produce branched-chain amino acids. By applying insights gained from structural and engineering studies of this enzyme family to a comprehensive multiple sequence alignment of KARIs, we identified putative NADH-utilizing KARIs and characterized eight whose catalytic efficiencies using NADH were equal to or greater than NADPH. These are the first naturally NADH-preferring KARIs reported and demonstrate that this property has evolved independently multiple times, using strategies unlike those used previously in the laboratory to engineer a KARI cofactor switch.", "date": "2014-11", "date_type": "published", "publication": "Metabolic Engineering", "volume": "26", "publisher": "Elsevier", "pagerange": "17-22", "id_number": "CaltechAUTHORS:20140902-115405020", "issn": "1096-7176", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140902-115405020", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF2809" }, { "agency": "Caltech Programmable Molecular Technology Initiative" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.ymben.2014.08.003", "primary_object": { "basename": "JACKSON-1-s2.0-S1096717614001062-main.pdf", "url": "https://authors.library.caltech.edu/records/zpqnb-ywg43/files/JACKSON-1-s2.0-S1096717614001062-main.pdf" }, "related_objects": [ { "basename": "mmc1.doc", "url": "https://authors.library.caltech.edu/records/zpqnb-ywg43/files/mmc1.doc" }, { "basename": "mmc2.doc", "url": "https://authors.library.caltech.edu/records/zpqnb-ywg43/files/mmc2.doc" } ], "pub_year": "2014", "author_list": "Brinkmann-Chen, S.; Cahn, J. K. B.; et al." }, { "id": "https://authors.library.caltech.edu/records/z71n8-58656", "eprint_id": 52797, "eprint_status": "archive", "datestamp": "2023-08-20 03:26:17", "lastmod": "2023-10-18 21:35:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yiyang", "name": { "family": "Liu", "given": "Yiyang" } }, { "id": "Liniger-M", "name": { "family": "Liniger", "given": "Marc" } }, { "id": "McFadden-R-M", "name": { "family": "McFadden", "given": "Ryan M." } }, { "id": "Roizen-J-L", "name": { "family": "Roizen", "given": "Jennifer L." }, "orcid": "0000-0002-6053-5512" }, { "id": "Malette-J", "name": { "family": "Malette", "given": "Jacquie" } }, { "id": "Reeves-C-M", "name": { "family": "Reeves", "given": "Corey M." } }, { "id": "Behenna-D-C", "name": { "family": "Behenna", "given": "Douglas C." } }, { "id": "Seto-Masaki", "name": { "family": "Seto", "given": "Masaki" } }, { "id": "Kim-Jimin", "name": { "family": "Kim", "given": "Jimin" } }, { "id": "Mohr-J-T", "name": { "family": "Mohr", "given": "Justin T." }, "orcid": "0000-0002-7005-3322" }, { "id": "Virgil-S-C", "name": { "family": "Virgil", "given": "Scott C." }, "orcid": "0000-0001-8586-5641" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Formal total syntheses of classic natural product target molecules via palladium-catalyzed enantioselective alkylation", "ispublished": "pub", "full_text_status": "public", "keywords": "enantioselective alkylation, natural products, palladium", "note": "\u00a9 2014, Liu et al; licensee Beilstein-Institut. This is an Open Access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The license is subject to the Beilstein Journal of Organic Chemistry terms and conditions: (http://www.beilstein-journals.org/bjoc).\n\nReceived: 11 August 2014. Accepted: 09 October 2014. Published: 28 October 2014. Associate Editor: S. Br\u00e4se. \n\nWe are grateful to NIH (R01GM080269), Amgen, the Gordon\nand Betty Moore Foundation, and Caltech for funding. We also\nthank the Caltech Minorities Undergraduate Research Fellowship program, PREM program, Eli Lilly, the Resnick Sustainability Institute at Caltech (fellowship for Y. L.), and the Swiss National Science Foundation (SNSF, fellowship for M. L.). Dr. Michael L. Krout and Dr. David E. White are acknowledged for preliminary experimental work related to their results. Dr. Michael Takase (Caltech) and Larry Henling (Caltech) are gratefully acknowledged for X-ray crystallographic structural determination.\n\n

Published - 1860-5397-10-261.pdf

Supplemental Material - Beilstein_J_Org_Chem-10-2501-s001.pdf

", "abstract": "Pd-catalyzed enantioselective alkylation in conjunction with further synthetic elaboration enables the formal total syntheses of a number of \"classic\" natural product target molecules. This publication highlights recent methods for setting quaternary and tetrasubstituted tertiary carbon stereocenters to address the synthetic hurdles encountered over many decades across multiple compound classes spanning carbohydrate derivatives, terpenes, and alkaloids. These enantioselective methods will impact both academic and industrial settings, where the synthesis of stereogenic quaternary carbons is a continuing challenge.", "date": "2014-10-28", "date_type": "published", "publication": "Beilstein Journal of Organic Chemistry", "volume": "10", "publisher": "Beilstein-Institut", "pagerange": "2501-2512", "id_number": "CaltechAUTHORS:20141215-084337170", "issn": "1860-5397", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141215-084337170", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NIH", "grant_number": "R01GM080269" }, { "agency": "Amgen" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Caltech" }, { "agency": "Caltech Minorities Undergraduate Research Fellowship (MURF)" }, { "agency": "PREM program" }, { "agency": "Eli Lilly" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Swiss National Science Foundation (SNSF)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.3762/bjoc.10.261", "pmcid": "PMC4222294", "primary_object": { "basename": "1860-5397-10-261.pdf", "url": "https://authors.library.caltech.edu/records/z71n8-58656/files/1860-5397-10-261.pdf" }, "related_objects": [ { "basename": "Beilstein_J_Org_Chem-10-2501-s001.pdf", "url": "https://authors.library.caltech.edu/records/z71n8-58656/files/Beilstein_J_Org_Chem-10-2501-s001.pdf" } ], "pub_year": "2014", "author_list": "Liu, Yiyang; Liniger, Marc; et al." }, { "id": "https://authors.library.caltech.edu/records/2c35e-s5p11", "eprint_id": 51157, "eprint_status": "archive", "datestamp": "2023-08-20 03:25:51", "lastmod": "2023-10-18 16:07:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Day-T-W", "name": { "family": "Day", "given": "Tristan W." } }, { "id": "Zeier-W-G", "name": { "family": "Zeier", "given": "Wolfgang G." } }, { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Melot-B-C", "name": { "family": "Melot", "given": "Brent C." } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Determining conductivity and mobility values of individual components in multiphase composite Cu_(1.97)Ag_(0.03)Se", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 AIP Publishing LLC. Received 12 August 2014; accepted 22 September 2014; published online 28 October 2014.\n\nT.W.D., D.R.B., and G.J.S. are grateful for the support\nof the AFOSR MURI program under FA9550-12-1-0002. D.R.B. acknowledges the support of the Resnick Institute. B.C.M. gratefully acknowledges financial support through start-up funding provided by the Dana and David Dornsife College of Letters and Sciences at the University of Southern California. W.G.Z. also acknowledges the support of a fellowship within the Postdoc-Program of the German\nAcademic Exchange Service (DAAD).\n\n

Published - 1.4897435.pdf

", "abstract": "The intense interest in phase segregation in thermoelectrics as a means to reduce the lattice thermal conductivity and to modify the electronic properties from nanoscale size effects has not been met with a method for separately measuring the properties of each phase assuming a classical mixture. Here, we apply effective medium theory for measurements of the in-line and Hall resistivity of a multiphase composite, in this case Cu_(1.97) Ag_(0.03)Se. The behavior of these properties with magnetic field as analyzed by effective medium theory allows us to separate the conductivity and charge carrier mobility of each phase. This powerful technique can be used to determine the matrix properties in the presence of an unwanted impurity phase, to control each phase in an engineered composite, and to determine the maximum carrier concentration change by a given dopant, making it the first step toward a full optimization of a multiphase thermoelectric material and distinguishing nanoscale effects from those of a classical mixture.", "date": "2014-10-27", "date_type": "published", "publication": "Applied Physics Letters", "volume": "105", "number": "17", "publisher": "American Institute of Physics", "pagerange": "Art. No. 172103", "id_number": "CaltechAUTHORS:20141103-090752822", "issn": "0003-6951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141103-090752822", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0002" }, { "agency": "Resnick Institute" }, { "agency": "University of Southern California Dana and Dornsife College of Letters and Sciences" }, { "agency": "German Academic Exchange Service (DAAD)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.4897435", "primary_object": { "basename": "1.4897435.pdf", "url": "https://authors.library.caltech.edu/records/2c35e-s5p11/files/1.4897435.pdf" }, "pub_year": "2014", "author_list": "Day, Tristan W.; Zeier, Wolfgang G.; et al." }, { "id": "https://authors.library.caltech.edu/records/drr6c-gp727", "eprint_id": 52379, "eprint_status": "archive", "datestamp": "2023-08-20 03:21:28", "lastmod": "2023-10-18 19:48:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jang-Min-Seok", "name": { "family": "Jang", "given": "Min Seok" }, "orcid": "0000-0002-5683-1925" }, { "id": "Brar-Victor-Watson", "name": { "family": "Brar", "given": "Victor W." } }, { "id": "Sherrott-Michelle-C", "name": { "family": "Sherrott", "given": "Michelle C." }, "orcid": "0000-0002-7503-9714" }, { "id": "Lopez-Josue-J", "name": { "family": "Lopez", "given": "Josue J." } }, { "id": "Kim-Laura", "name": { "family": "Kim", "given": "Laura" } }, { "id": "Kim-Seyoon", "name": { "family": "Kim", "given": "Seyoon" }, "orcid": "0000-0002-8040-9521" }, { "id": "Choi-Mansoo", "name": { "family": "Choi", "given": "Mansoo" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Tunable large resonant absorption in a midinfrared graphene Salisbury screen", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Physical Society. \n\nReceived 24 March 2014; Published 8 October 2014. \n\nThis work was supported by the Air Force Office of Scientific Research under Multidisciplinary University Research Initiative Awards No. FA9550-12-1-0488 (V.W.B.), FA9550-12-1-0024 (S.K. and L.K.K.), and the Department of Energy, Office of Science, under Grant No. DE-FG02-07ER46405 (M.C.S. and H.A.A.). M. S. Jang and M. Choi acknowledge support from the R&D Program of the Global Frontier Center for Multiscale Energy Systems funded by the National Research Foundation under the Ministry of Science, ITC & Future Planning, Korea (Grants No. 2011-0031561 and No. 2011-0031577). M. S. Jang acknowledges a postdoctoral fellowship from the POSCO T. J. Park Foundation. V. W. Brar gratefully acknowledges a postdoctoral fellowship from the Kavli Nanoscience Institute. M. C. Sherrott gratefully acknowledges graduate fellowship support from the Resnick Sustainability Institute at Caltech. S. Kim and M. S. Jang acknowledge support from a Samsung Fellowship.\n\n

Published - PhysRevB.90.165409.pdf

Submitted - 1312.6463.pdf

Supplemental Material - Supple.pdf

", "abstract": "The optical absorption properties of periodically patterned graphene plasmonic resonators are studied experimentally as the graphene sheet is placed near a metallic reflector. By varying the size and carrier density of the graphene, the parameters for achieving a surface impedance closely matched to free-space (Z_0 = 377\u03a9) are determined and shown to result in 24.5% total optical absorption in the graphene sheet. Theoretical analysis shows that complete absorption is achievable with higher doping or lower loss. This geometry, known as a Salisbury screen, provides an efficient means of light coupling to the highly confined graphene plasmonic modes for future optoelectronic applications.", "date": "2014-10-15", "date_type": "published", "publication": "Physical Review B", "volume": "90", "number": "16", "publisher": "American Physical Society", "pagerange": "Art. No. 165409", "id_number": "CaltechAUTHORS:20141204-101624900", "issn": "1098-0121", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141204-101624900", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0488" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0024" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "National Research Foundation of Korea", "grant_number": "2011-0031561" }, { "agency": "National Research Foundation of Korea", "grant_number": "2011-0031577" }, { "agency": "POSCO TJ Park Foundation" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Samsung" }, { "agency": "Ministry of Science, ICT and Future Planning (Korea)" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.90.165409", "primary_object": { "basename": "1312.6463.pdf", "url": "https://authors.library.caltech.edu/records/drr6c-gp727/files/1312.6463.pdf" }, "related_objects": [ { "basename": "PhysRevB.90.165409.pdf", "url": "https://authors.library.caltech.edu/records/drr6c-gp727/files/PhysRevB.90.165409.pdf" }, { "basename": "Supple.pdf", "url": "https://authors.library.caltech.edu/records/drr6c-gp727/files/Supple.pdf" } ], "pub_year": "2014", "author_list": "Jang, Min Seok; Brar, Victor W.; et al." }, { "id": "https://authors.library.caltech.edu/records/rfp5z-vjz67", "eprint_id": 49332, "eprint_status": "archive", "datestamp": "2023-08-22 13:56:31", "lastmod": "2023-10-17 21:19:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dodani-S-C", "name": { "family": "Dodani", "given": "Sheel C." } }, { "id": "Cahn-J-K-B", "name": { "family": "Cahn", "given": "Jackson K. B." } }, { "id": "Heinisch-T", "name": { "family": "Heinisch", "given": "Tillmann" } }, { "id": "Brinkmann-Chen-S", "name": { "family": "Brinkmann-Chen", "given": "Sabine" }, "orcid": "0000-0002-5419-4192" }, { "id": "McIntosh-J-A", "name": { "family": "McIntosh", "given": "John A." }, "orcid": "0000-0002-9487-490X" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Structural, Functional, and Spectroscopic Characterization of the Substrate Scope of the Novel Nitrating Cytochrome P450 TxtE", "ispublished": "pub", "full_text_status": "public", "keywords": "aromatic nitration; crystal-structure determination; cytochromes; enzyme catalysis", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: May 15, 2014. Published online on September 2, 2014.\n\nWe thank Dr. Jens Kaiser and Dr. Pavle Nikolovski of the Beckman Molecular Observatory (Caltech) for assistance with crystallography and Dr. Scott Virgil and the 3CS Center for Catalysis and Chemical Synthesis (Caltech) for assistance with LC-MS analyses. The authors thank the Resnick Sustainability Institute (Caltech) (support to J.K.B.C.) and Dow Chemical Company for support through the Dow-Resnick innovation program. S.C.D. and J.A.M. are supported by Ruth L. Kirschstein NRSA postdoctoral fellowships from the National Institutes of Health (5F32M106618 and 5F32M101792, respectively). T.H. is supported by a postdoctoral fellowship from the Swiss National Science Foundation (Fellowship PBBSP2_146809). The Beckman Molecular Observatory is supported by the Gordon and Betty Moore Foundation, the Beckman Institute, and the Sanofi-Aventis Bioengineering Research Program (Caltech). The authors thank Dr. Fei Sun for sharing of the XL1-Blue E. coli strain and helpful discussions. The content of\nthis paper is solely the responsibility of the authors and does not represent the official views of any of the funding agencies.\n\n

Accepted Version - nihms637153.pdf

Supplemental Material - cbic_201402241_sm_miscellaneous_information.pdf

", "abstract": "A novel cytochrome P450 enzyme, TxtE, was recently shown to catalyze the direct aromatic nitration of L-tryptophan. This unique chemistry inspired us to ask whether TxtE could serve as a platform for engineering new nitration biocatalysts to replace current harsh synthetic methods. As a first step toward this goal, and to better understand the wild-type enzyme, we obtained high-resolution structures of TxtE in its substrate-free and substrate-bound forms. We also screened a library of substrate analogues for spectroscopic indicators of binding and for production of nitrated products. From these results, we found that the wild-type enzyme accepts moderate decoration of the indole ring, but the amino acid moiety is crucial for binding and correct positioning of the substrate and therefore less amenable to modification. A nitrogen atom is essential for catalysis, and a carbonyl must be present to recruit the \u03b1B\u20321 helix of the protein to seal the binding pocket.", "date": "2014-10-13", "date_type": "published", "publication": "ChemBioChem", "volume": "15", "number": "15", "publisher": "Wiley", "pagerange": "2259-2267", "id_number": "CaltechAUTHORS:20140908-101026220", "issn": "1439-4227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140908-101026220", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Dow Chemical Company" }, { "agency": "NIH Postdoctoral Fellowship", "grant_number": "5F32M106618" }, { "agency": "NIH Postdoctoral Fellowship", "grant_number": "5F32M101792" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "PBBSP2_146809" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/cbic.201402241", "pmcid": "PMC4260628", "primary_object": { "basename": "cbic_201402241_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/rfp5z-vjz67/files/cbic_201402241_sm_miscellaneous_information.pdf" }, "related_objects": [ { "basename": "nihms637153.pdf", "url": "https://authors.library.caltech.edu/records/rfp5z-vjz67/files/nihms637153.pdf" } ], "pub_year": "2014", "author_list": "Dodani, Sheel C.; Cahn, Jackson K. B.; et al." }, { "id": "https://authors.library.caltech.edu/records/k34zn-a2j35", "eprint_id": 51697, "eprint_status": "archive", "datestamp": "2023-08-20 02:20:38", "lastmod": "2023-10-18 17:03:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-N", "name": { "family": "Li", "given": "Na" } }, { "id": "Marden-J-R", "name": { "family": "Marden", "given": "Jason R." } } ] }, "title": "Decoupling Coupled Constraints Through Utility Design", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Game theory, multiagent systems, networked control systems", "note": "\u00a9 2014 IEEE.\n\nManuscript received June 10, 2011; revised December 26, 2011; accepted\nFebruary 4, 2013. Date of publication February 3, 2014; date of current version\nJuly 21, 2014. This technical note appeared in part at the 49th IEEE Conference\non Decision and Control, 2010. \n\nThis work was supported by AFOSR\ngrants #FA9550-09-1-0538 and #FA9550-12-1-0359, ONR grant #N00014-12-1-0643, NSF NetSE grant #CNS-0911041, ARPA-E grant #DE-AR0000226,\nSouthern California Edison, the Caltech Resnick Institute, and the Okawa Foundation. Recommended by Associate Editor H. S. Chang.", "abstract": "Several multiagent systems exemplify the need for establishing distributed control laws that ensure the resulting agents' collective behavior satisfies a given coupled constraint. This technical note focuses on the design of such control laws through a game-theoretic framework. In particular, this technical note provides two systematic methodologies for the design of local agent objective functions that guarantee all resulting Nash equilibria optimize the system level objective while also satisfying a given coupled constraint. Furthermore, the designed local agent objective functions fit into the framework of state based potential games. Consequently, one can appeal to existing results in game-theoretic learning to derive a distributed process that guarantees the agents will reach such an equilibrium.", "date": "2014-08", "date_type": "published", "publication": "IEEE Transactions on Automatic Control", "volume": "59", "number": "8", "publisher": "IEEE", "pagerange": "2289-2294", "id_number": "CaltechAUTHORS:20141113-083218226", "issn": "0018-9286", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141113-083218226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-09-1-0538" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0359" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-12-1-0643" }, { "agency": "NSF NetSE", "grant_number": "CNS-0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "Caltech Resnick Institute" }, { "agency": "Okawa Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TAC.2014.2304373", "pub_year": "2014", "author_list": "Li, Na and Marden, Jason R." }, { "id": "https://authors.library.caltech.edu/records/fqac2-kv940", "eprint_id": 46173, "eprint_status": "archive", "datestamp": "2023-08-22 13:10:23", "lastmod": "2025-04-23 01:08:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brar-V-W", "name": { "family": "Brar", "given": "Victor W." } }, { "id": "Jang-Min-Seok", "name": { "family": "Jang", "given": "Min Seok" }, "orcid": "0000-0002-5683-1925" }, { "id": "Sherrott-M-C", "name": { "family": "Sherrott", "given": "Michelle" }, "orcid": "0000-0002-7503-9714" }, { "id": "Kim-Seyoon", "name": { "family": "Kim", "given": "Seyoon" }, "orcid": "0000-0002-8040-9521" }, { "id": "Lopez-J-J", "name": { "family": "Lopez", "given": "Josue J." } }, { "id": "Kim-Laura", "name": { "family": "Kim", "given": "Laura B." } }, { "id": "Choi-Mansoo", "name": { "family": "Choi", "given": "Mansoo" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry" }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Hybrid Surface-Phonon-Plasmon Polariton Modes in Graphene/Monolayer h-BN Heterostructures", "ispublished": "pub", "full_text_status": "public", "keywords": "Graphene; boron nitride; plasmonics; strong coupling; phonon-induced transparency; surface phonon plasmon polariton; plasmon phonon hybridization", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: March 24, 2014; Revised: May 20, 2014. Publication Date (Web): May 29, 2014. \n\nThis work was supported by the Air Force Office of Scientific Research under MURI awards FA9550-12-1-0488 (V.W.B.), FA9550-12-1-0024 (S.K. and L.K.K.). M.S.J. and M.C. acknowledge support from the Global Frontier R&D Program on Center for Multiscale Energy Systems funded by the National Research Foundation under the Ministry of Science, ITC & Future Planning, Korea (2011-0031561, 2011-0031577). M.S.J. acknowledges a postdoctoral fellowship from the POSCO TJ Park Foundation. M.C.S. gratefully\nacknowledges graduate fellowship support from the Resnick\nSustainability Institute at Caltech. The authors thank the Kavli Nanoscience Institute at Caltech for support of nanofabrication.\n\n

Supplemental Material - nl501096s_si_001.pdf

", "abstract": "Infrared transmission measurements reveal the hybridization of graphene plasmons and the phonons in a monolayer hexagonal boron nitride (h-BN) sheet. Frequency-wavevector dispersion relations of the electromagnetically coupled graphene plasmon/h-BN phonon modes are derived from measurement of nanoresonators with widths varying from 30 to 300 nm. It is shown that the graphene plasmon mode is split into two distinct optical modes that display an anticrossing behavior near the energy of the h-BN optical phonon at 1370 cm^(\u20131). We explain this behavior as a classical electromagnetic strong-coupling with the highly confined near fields of the graphene plasmons allowing for hybridization with the phonons of the atomically thin h-BN layer to create two clearly separated new surface-phonon-plasmon-polariton (SPPP) modes.", "date": "2014-07-09", "date_type": "published", "publication": "Nano Letters", "volume": "14", "number": "7", "publisher": "American Chemical Society", "pagerange": "3876-3880", "id_number": "CaltechAUTHORS:20140610-084252887", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140610-084252887", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0488" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0024" }, { "agency": "Global Frontier R&D Program on Center for Multiscale Energy Systems" }, { "agency": "National Research Foundation of Korea", "grant_number": "2011-0031561" }, { "agency": "National Research Foundation of Korea", "grant_number": "2011-0031577" }, { "agency": "POSCO TJ Park Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Ministry of Science, ICT and Future Planning (Korea)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/nl501096s", "primary_object": { "basename": "nl501096s_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fqac2-kv940/files/nl501096s_si_001.pdf" }, "pub_year": "2014", "author_list": "Brar, Victor W.; Jang, Min Seok; et al." }, { "id": "https://authors.library.caltech.edu/records/f2f1j-1v334", "eprint_id": 46157, "eprint_status": "archive", "datestamp": "2023-08-20 01:18:45", "lastmod": "2025-04-23 03:14:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kosten-E-D", "name": { "family": "Kosten", "given": "Emily D." } }, { "id": "Kayes-B-M", "name": { "family": "Kayes", "given": "Brendan M." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Experimental demonstration of enhanced photon recycling in angle-restricted GaAs solar cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 31 Oct 2013, Accepted 15 Apr 2014,\nFirst published online 15 Apr 2014.\n\nThanks to M. Sheldon, E. Warmann, J. Bosco, and C. Eisler for\nuseful discussions and comments and to J. Lloyd for assistance\nwith figure preparation. This work was supported by the the\n'Light-Material Interactions in Energy Conversion' Energy\nFrontier Research Center funded by the U.S. Department of\nEnergy, Office of Science, Office of Basic Energy Sciences under\nAward Number DE-SC0001293. E.K. is also the recipient of a\nResnick Sustainability Institute Graduate Fellowship.\n\n

Published - c3ee43584a.pdf

Supplemental Material - c3ee43584a1_si.pdf

", "abstract": "For cells near the radiative limit, optically limiting the angles of emitted light causes emitted photons to be recycled back to the cell, leading to enhancement in voltage and efficiency. While this has been understood theoretically for some time, only recently have GaAs cells reached sufficient quality for the effect to be experimentally observed. Here, as proof of concept, we demonstrate enhanced photon recycling and open-circuit voltage (V_(oc)) experimentally using a narrow band dielectric multilayer angle restrictor on a high quality GaAs cell. With angle restriction we observe a clear decrease in the radiative dark current, which is consistent with the observed V_(oc) increase. Furthermore, we observe larger V_(oc) enhancements for cells that are closer to the radiative limit, and that more closely coupling the angle restrictor to the cell leads to greater V_(oc) gains, emphasizing the optical nature of the effect.", "date": "2014-06-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1907-1912", "id_number": "CaltechAUTHORS:20140609-132709772", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140609-132709772", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c3ee43584a", "primary_object": { "basename": "c3ee43584a1_si.pdf", "url": "https://authors.library.caltech.edu/records/f2f1j-1v334/files/c3ee43584a1_si.pdf" }, "related_objects": [ { "basename": "c3ee43584a.pdf", "url": "https://authors.library.caltech.edu/records/f2f1j-1v334/files/c3ee43584a.pdf" } ], "pub_year": "2014", "author_list": "Kosten, Emily D.; Kayes, Brendan M.; et al." }, { "id": "https://authors.library.caltech.edu/records/jdcgw-gqx82", "eprint_id": 60423, "eprint_status": "archive", "datestamp": "2023-08-20 01:13:36", "lastmod": "2023-10-24 16:32:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Convex Relaxation of Optimal Power Flow - Part II: Exactness", "ispublished": "pub", "full_text_status": "public", "keywords": "Convex relaxation, optimal power flow, power systems, quadratically constrained quadratic program (QCQP), second-order cone program (SOCP), semidefinite program (SDP), semidefinite relaxation", "note": "\u00a9 2014 IEEE. Open Access. \n\nManuscript received September 23, 2013; revised April 8, 2014. Date of publication May 14, 2014; date of current version June 16, 2014. This work was supported in part by NSF through NetSE CNS 0911041, in part by ARPA-E through GENI DE-AR0000226, Southern California Edison, in part by the National Science Council of Taiwan through NSC 103-3113-P-008-001, in part by the Los Alamos National Lab (DoE), and in part by Caltech's Resnick Institute. \n\nA preliminary and abridged version has appeared in Proc. IREP Symp. Bulk Power Syst. Dynam. Control-IX (IREP), Rethymnon, Greece, August 25\u201330, 2013.\n\n

Published - 06815671.pdf

Submitted - 1405.0814.pdf

", "abstract": "This tutorial summarizes recent advances in the convex relaxation of the optimal power flow (OPF) problem, focusing on structural properties rather than algorithms. Part I presents two power flow models, formulates OPF and their relaxations in each model, and proves equivalence relations among them. Part II presents sufficient conditions under which the convex relaxations are exact.", "date": "2014-06", "date_type": "published", "publication": "IEEE Transactions on Control of Network Systems", "volume": "1", "number": "2", "publisher": "IEEE", "pagerange": "177-189", "id_number": "CaltechAUTHORS:20150922-153930585", "issn": "2325-5870", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150922-153930585", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Los Alamos National Laboratory" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TCNS.2014.2323634", "primary_object": { "basename": "1405.0814.pdf", "url": "https://authors.library.caltech.edu/records/jdcgw-gqx82/files/1405.0814.pdf" }, "related_objects": [ { "basename": "06815671.pdf", "url": "https://authors.library.caltech.edu/records/jdcgw-gqx82/files/06815671.pdf" } ], "pub_year": "2014", "author_list": "Low, Steven H." }, { "id": "https://authors.library.caltech.edu/records/05scm-3hp82", "eprint_id": 47307, "eprint_status": "archive", "datestamp": "2023-08-20 01:08:56", "lastmod": "2023-10-26 20:29:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Pei-Yanzhong", "name": { "family": "Pei", "given": "Yanzhong" } }, { "id": "Wang-Heng", "name": { "family": "Wang", "given": "Heng" } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Linear dependence of the Hall coefficient of 1% Na doped PbTe with varying magnetic field", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Hall effect, lead chalcogenides, minority carriers, thermoelectrics", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. Received 14 May 2013, revised 14 December 2013, accepted 4 March 2014.\nPublished online 1 May 2014. Article first published online: 6 May 2014. The authors would like to acknowledge\nthe assistance of C. Jaworski and J. Heremans. G.J.S. and D.R. B. acknowledge the Air Force Office of Science Research MURI FA9550-12-1-0002. D.R.B. acknowledges the support of the Resnick Institute. Y.P. acknowledges the Recruitment Program of Global Experts (1000 Plan) of China, the program for professor of special appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning, Pujiang project of Shanghai Science and Technology\nCommission (13PJ1408400) and the Bayer-Tongji Eco-Construction\n& Material Academy (TB20140001) for funding support.", "abstract": "Heavily p-doped PbTe is known to be a highly efficient thermoelectric material and theories explaining this have connected it to positive curvature in the Seebeck coefficient between 300 and 500\u2009K and a peak in the Hall coefficient at 500\u2009K due to band convergence. Recent work by Jaworski et al. has suggested that a pocket of high mobility electrons between the L and Sigma point in the Brillouin zone are responsible for these effects, inferred from an observed inversion of the Hall resistivity under small magnetic fields (<0.5\u2009T). Here the Hall resistivity of 1% Na doped PbTe is measured in magnetic fields ranging from 0.1 to 2\u2009T at 293 and 626\u2009K and found to be linear without any inversion of Hall resistivity.", "date": "2014-06", "date_type": "published", "publication": "Physica Status Solidi A", "volume": "211", "number": "6", "publisher": "Wiley", "pagerange": "1273-1275", "id_number": "CaltechAUTHORS:20140717-153357111", "issn": "1862-6300", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140717-153357111", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0002" }, { "agency": "Resnick Institute" }, { "agency": "Recruitment Program of Global Experts (1000 Plan) of China" }, { "agency": "Shanghai Institutions of Higher Learning, Pujiang project of Shanghai Science and Technology Commission", "grant_number": "13PJ1408400" }, { "agency": "Bayer-Tongji Eco-Construction & Material Academy", "grant_number": "TB20140001" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/pssa.201300118", "pub_year": "2014", "author_list": "Brown, David R.; Pei, Yanzhong; et al." }, { "id": "https://authors.library.caltech.edu/records/fqd0g-9fy53", "eprint_id": 45771, "eprint_status": "archive", "datestamp": "2023-08-20 01:03:35", "lastmod": "2023-10-26 18:27:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Beardslee-J-A", "name": { "family": "Beardslee", "given": "Joseph A." } }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael" }, "orcid": "0000-0002-0710-7068" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Amorphous TiO_2 coatings stabilize Si, GaAs, and GaP photoanodes for efficient water oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Association for the Advancement of Science. \n\nReceived for publication 28 January 2014. Accepted for publication 1 May 2014. \n\nThis work is supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. M.S. acknowledges the Resnick Sustainability Institute for a graduate fellowship, and B.S.B. acknowledges the Beckman Institute at the California Institute of Technology for support. XPS was performed at the Molecular Materials Research Center in the Beckman Institute at the California Institute of Technology. TEM imaging and spectroscopy were performed at the Center for Electron Microscopy and Microanalysis, University of Southern California. We thank H.- J. Lewerenz, C. Koval, and F. Houle for fruitful discussions; Y. Guan for secondary-ion mass spectrometry measurements; S. R. Nutt for use of the microscopy and microanalysis facility; P. D. Dapkus for the use of the metal-organic chemical vapor deposition facility; S. Ardo for help in boron-diffusion doping; and K. Papadantonakis for assistance with editing this manuscript. The authors' institution (California Institute of Technology) has filed a provisional U.S. patent application directly relating to the work described in the paper (patent application no. 61/889,430, filed on 10 October 2013).\n\n

Supplemental Material - Hu.S.SM.pdf

", "abstract": "Although semiconductors such as silicon (Si), gallium arsenide (GaAs), and gallium phosphide (GaP) have band gaps that make them efficient photoanodes for solar fuel production, these materials are unstable in aqueous media. We show that TiO_2 coatings (4 to 143 nanometers thick) grown by atomic layer deposition prevent corrosion, have electronic defects that promote hole conduction, and are sufficiently transparent to reach the light-limited performance of protected semiconductors. In conjunction with a thin layer or islands of Ni oxide electrocatalysts, Si photoanodes exhibited continuous oxidation of 1.0 molar aqueous KOH to O_2 for more than 100 hours at photocurrent densities of >30 milliamperes per square centimeter and ~100% Faradaic efficiency. TiO_2-coated GaAs and GaP photoelectrodes exhibited photovoltages of 0.81 and 0.59 V and light-limiting photocurrent densities of 14.3 and 3.4 milliamperes per square centimeter, respectively, for water oxidation.", "date": "2014-05-30", "date_type": "published", "publication": "Science", "volume": "344", "number": "6187", "publisher": "American Association for the Advancement of Science", "pagerange": "1005-1009", "id_number": "CaltechAUTHORS:20140515-133039268", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140515-133039268", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1126/science.1251428", "primary_object": { "basename": "Hu.S.SM.pdf", "url": "https://authors.library.caltech.edu/records/fqd0g-9fy53/files/Hu.S.SM.pdf" }, "pub_year": "2014", "author_list": "Hu, Shu; Shaner, Matthew R.; et al." }, { "id": "https://authors.library.caltech.edu/records/6m85q-jgw24", "eprint_id": 45059, "eprint_status": "archive", "datestamp": "2023-08-20 00:56:57", "lastmod": "2025-04-25 03:21:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ravichandran-Navaneetha-K", "name": { "family": "Ravichandran", "given": "Navaneetha K." } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Coherent and Incoherent Thermal Transport in Nanomeshes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Physical Society.\nReceived 12 November 2013; revised manuscript received 17 March 2014; published 27 May 2014.\nThis work is part of the \"Light-Material Interactions in\nEnergy Conversion\" Energy Frontier Research Center funded\nby the US Department of Energy, Office of Science, Office of\nBasic Energy Sciences under Award No. DE-SC0001293.\n\n

Published - PhysRevB.89.205432.pdf

Submitted - 1403.7647v1.pdf

", "abstract": "Coherent thermal transport in nanopatterned structures is a topic of considerable interest, but whether it occurs in certain structures remains unclear due to a poor understanding of which phonons conduct heat. Here, we perform fully three-dimensional, frequency-dependent simulations of thermal transport in nanomeshes by solving the Boltzmann transport equation with an efficient Monte Carlo method. From the spectral information in our simulations, we show that thermal transport in nanostructures that can be created with available lithographic techniques is dominated by incoherent boundary scattering at room temperature. Our result provides important insights into the conditions required for coherent thermal transport to occur in artificial structures.", "date": "2014-05-15", "date_type": "published", "publication": "Physical Review B", "volume": "89", "number": "20", "publisher": "American Physical Society", "pagerange": "Art. No. 205432", "id_number": "CaltechAUTHORS:20140421-080824072", "issn": "1098-0121", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140421-080824072", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE) Light Material Interactions Energy Frontier Research Center", "grant_number": "DE-SC0001293" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.89.205432", "primary_object": { "basename": "1403.7647v1.pdf", "url": "https://authors.library.caltech.edu/records/6m85q-jgw24/files/1403.7647v1.pdf" }, "related_objects": [ { "basename": "PhysRevB.89.205432.pdf", "url": "https://authors.library.caltech.edu/records/6m85q-jgw24/files/PhysRevB.89.205432.pdf" } ], "pub_year": "2014", "author_list": "Ravichandran, Navaneetha K. and Minnich, Austin J." }, { "id": "https://authors.library.caltech.edu/records/srhae-p5128", "eprint_id": 45963, "eprint_status": "archive", "datestamp": "2023-08-20 00:32:54", "lastmod": "2023-10-26 18:34:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Changhong", "name": { "family": "Zhao", "given": "Changhong" }, "orcid": "0000-0003-0539-8591" }, { "id": "Topcu-U", "name": { "family": "Topcu", "given": "Ufuk" } }, { "id": "Li-Na", "name": { "family": "Li", "given": "Na" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven" }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Design and Stability of Load-Side Primary Frequency Control in Power Systems", "ispublished": "pub", "full_text_status": "public", "keywords": "Decentralized control, optimization, power\nsystem control, power system dynamics.", "note": "\u00a9 2014 IEEE. Manuscript received May 05, 2013; revised October 24, 2013; accepted December 04, 2013. Date of publication January 09, 2014; date of current version April 18, 2014. \n\nThis paper appeared in part at the Proceedings of the\n3rd IEEE International Conference on Smart Grid Communications, 2012. \n\nThis work was supported by NSF CNS award 1312390, NSF NetSE grant CNS 0911041, ARPA-E grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan R.O.C. grant NSC 103-3113-P-008-001,\nCaltech Resnick Institute, and California Energy Commission's Small Grant Program through Grant 57360A/11-16. Recommended by Associate Editor L. Schenato. The authors would like to thank the anonymous referees for their careful reviews and valuable comments and suggestions,\nJ. Bialek, R. Baldick, J. Lin, L. Tong, and F.Wu for very helpful discussions on the dynamic network model, L. Chen for discussions on the analytic approach, and A. Brooks, AeroVironment, for suggestions on practical issues.\n\n

Submitted - 1305.0585v3.pdf

", "abstract": "We present a systematic method to design ubiquitous continuous fast-acting distributed load control for primary frequency regulation in power networks, by formulating an optimal load control (OLC) problem where the objective is to minimize the aggregate cost of tracking an operating point subject to power balance over the network. We prove that the swing dynamics and the branch power flows, coupled with frequency-based load control, serve as a distributed primal-dual algorithm to solve OLC. We establish the global asymptotic stability of a multimachine network under such type of load-side primary frequency control. These results imply that the local frequency deviations on each bus convey exactly the right information about the global power imbalance for the loads to make individual decisions that turn out to be globally optimal. Simulations confirm that the proposed algorithm can rebalance power and resynchronize bus frequencies after a disturbance with significantly improved transient performance.", "date": "2014-05", "date_type": "published", "publication": "IEEE Transactions on Automatic Control", "volume": "59", "number": "5", "publisher": "IEEE", "pagerange": "1177-1189", "id_number": "CaltechAUTHORS:20140529-094709292", "issn": "0018-9286", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140529-094709292", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-1312390" }, { "agency": "NSF NetSE", "grant_number": "CNS-0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Caltech Resnick Institute" }, { "agency": "California Energy Commission", "grant_number": "57360A/11-16" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TAC.2014.2298140", "primary_object": { "basename": "1305.0585v3.pdf", "url": "https://authors.library.caltech.edu/records/srhae-p5128/files/1305.0585v3.pdf" }, "pub_year": "2014", "author_list": "Zhao, Changhong; Topcu, Ufuk; et al." }, { "id": "https://authors.library.caltech.edu/records/nrsag-pw466", "eprint_id": 44728, "eprint_status": "archive", "datestamp": "2023-08-20 00:21:05", "lastmod": "2025-04-23 03:16:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Leenheer-A-J", "name": { "family": "Leenheer", "given": "Andrew J." } }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Solar energy conversion via hot electron internal photoemission in metallic nanostructure: Efficiency estimates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Institute of Physics Publishing LLC. Received 31 October 2013; accepted 15 February 2014; published online 1 April 2014. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy\nInnovation Hub, supported through the Office of Science of\nthe U.S. Department of Energy under Award No. DESC0004993.\nP.N. is supported by a National Science\nFoundation Graduate Research Fellowship and by the\nResnick Sustainability Institute.\n\n

Published - 1.4870040.pdf

", "abstract": "Collection of hot electrons generated by the efficient absorption of light in metallic nanostructures, in contact with semiconductor substrates can provide a basis for the construction of solar energy-conversion devices. Herein, we evaluate theoretically the energy-conversion efficiency of systems that rely on internal photoemission processes at metal-semiconductor Schottky-barrier diodes. In this theory, the current-voltage characteristics are given by the internal photoemission yield as well as by the thermionic dark current over a varied-energy barrier height. The Fowler model, in all cases, predicts solar energy-conversion efficiencies of <1% for such systems. However, relaxation of the assumptions regarding constraints on the escape cone and momentum conservation at the interface yields solar energy-conversion efficiencies as high as 1%\u201310%, under some assumed (albeit optimistic) operating conditions. Under these conditions, the energy-conversion efficiency is mainly limited by the thermionic dark current, the distribution of hot electron energies, and hot-electron momentum considerations.", "date": "2014-04-07", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "115", "number": "13", "publisher": "American Institute of Physics", "pagerange": "Art. No. 134301", "id_number": "CaltechAUTHORS:20140408-084811849", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140408-084811849", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1063/1.4870040", "primary_object": { "basename": "1.4870040.pdf", "url": "https://authors.library.caltech.edu/records/nrsag-pw466/files/1.4870040.pdf" }, "pub_year": "2014", "author_list": "Leenheer, Andrew J.; Narang, Prineha; et al." }, { "id": "https://authors.library.caltech.edu/records/hkyz6-w6p45", "eprint_id": 43144, "eprint_status": "archive", "datestamp": "2023-08-19 23:35:00", "lastmod": "2023-10-25 23:18:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Meza-L-R", "name": { "family": "Meza", "given": "Lucas R." }, "orcid": "0000-0003-0250-2621" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "Mechanical characterization of hollow ceramic nanolattices", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 Springer Science+Business Media New York.\n\nReceived: 28 September 2013; Accepted: 2 December 2013. Published online December 18, 2013. \n\nThe authors gratefully acknowledge the financial support from the Dow-Resnick Innovation Fund at Caltech, the Office of Naval Research (Grant N000140910883) and the Army Research Office through the Institute for Collaborative Biotechnologies (ICB) at Caltech (ARO Award number UCSB.ICB4b). Part of this work was carried out at the Jet Propulsion Laboratory under a contract with NASA. The authors acknowledge critical support and infrastructure provided by the Kavli Nanoscience Institute at Caltech. The authors thank Dongchan Jang for his help with nanomechanical experiments. The authors also thank Frank Greer for his help in the ALD deposition of the TiN films.", "abstract": "In the analysis of complex, hierarchical structural meta-materials, it is critical to understand the mechanical behavior at each level of hierarchy in order to understand the bulk material response. We report the fabrication and mechanical deformation of hierarchical hollow tube lattice structures with features ranging from 10 nm to 100 \u03bcm, hereby referred to as nanolattices. Titanium nitride (TiN) nanolattices were fabricated using a combination of two-photon lithography, direct laser writing, and atomic layer deposition. The structure was composed of a series of tessellated regular octahedra attached at their vertices. In situ uniaxial compression experiments performed in combination with finite element analysis on individual unit cells revealed that the TiN was able to withstand tensile stresses of 1.75 GPa under monotonic loading and of up to 1.7 GPa under cyclic loading without failure. During the compression of the unit cell, the beams bifurcated via lateral-torsional buckling, which gave rise to a hyperelastic behavior in the load\u2013displacement data. During the compression of the full nanolattice, the structure collapsed catastrophically at a high strength and modulus that agreed well with classical cellular solid scaling laws given the low relative density of 1.36 %. We discuss the compressive behavior and mechanical analysis of the unit cell of these hollow TiN nanolattices in the context of finite element analysis in combination with classical buckling laws, and the behavior of the full structure in the context of classical scaling laws of cellular solids coupled with enhanced nanoscale material properties.", "date": "2014-03", "date_type": "published", "publication": "Journal of Materials Science", "volume": "49", "number": "6", "publisher": "Springer", "pagerange": "2496-2508", "id_number": "CaltechAUTHORS:20131223-110132955", "issn": "0022-2461", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131223-110132955", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Dow-Resnick Innovation Fund" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N000140910883" }, { "agency": "Army Research Office (ARO)", "grant_number": "UCSB.ICB4b" }, { "agency": "NASA/JPL" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s10853-013-7945-x", "pub_year": "2014", "author_list": "Meza, Lucas R. and Greer, Julia R." }, { "id": "https://authors.library.caltech.edu/records/436tr-60p50", "eprint_id": 45868, "eprint_status": "archive", "datestamp": "2023-08-19 23:43:54", "lastmod": "2023-10-26 18:30:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Convex Relaxation of Optimal Power Flow \u2014 Part I: Formulations and Equivalence", "ispublished": "pub", "full_text_status": "public", "keywords": "Convex relaxation, optimal power flow, power systems, quadratically constrained quadratic program (QCQP), second-order cone program (SOCP), semidefinite program (SDP), semidefinite relaxation", "note": "\u00a9 2014 IEEE. \n\nManuscript received September 23, 2013; revised February 5, 2014; February 19, 2014; accepted February 28, 2014. Date of publication March 5, 2014; date of current version April 9, 2014. \n\nThis work was supported in part by NSF under Grant NetSE CNS 0911041, in part by ARPA-E under Grant GENI DE-AR0000226, in part by the National Science Council of Taiwan under Grant NSC 103-3113-P-008-001, in part by Southern California Edison, in part by the Los Alamos National Lab,and in part by Caltech's Resnick Institute. A preliminary and abridged version has appeared in [S. H. Low, \"Convex relaxation of optimal power flow: A tutorial,\" in Proc. IREP Symp. Bulk Power Syst. Dyn. Control(IREP), Rethymnon, Greece, Aug. 2013.]. Recommended by Associate Editor M. Chertkov. \n\nWe thank the anonymous reviewers for their helpful suggestions.\n\n

Submitted - 1405.0766.pdf

", "abstract": "This tutorial summarizes recent advances in the convex\nrelaxation of the optimal power flow (OPF) problem, focusing on structural properties rather than algorithms. Part I presents two power flow models, formulates OPF and their relaxations in each model, and proves equivalence relationships among them. Part II presents sufficient conditions under which the convex relaxations are exact.", "date": "2014-03", "date_type": "published", "publication": "IEEE Transactions on Control of Network Systems", "volume": "1", "number": "1", "publisher": "IEEE", "pagerange": "15-27", "id_number": "CaltechAUTHORS:20140521-104006650", "issn": "2325-5870", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140521-104006650", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 103-3113-P-008-001" }, { "agency": "Southern California Edison" }, { "agency": "Los Alamos National Laboratory" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TCNS.2014.2309732", "primary_object": { "basename": "1405.0766.pdf", "url": "https://authors.library.caltech.edu/records/436tr-60p50/files/1405.0766.pdf" }, "pub_year": "2014", "author_list": "Low, Steven H." }, { "id": "https://authors.library.caltech.edu/records/a14fd-faw27", "eprint_id": 42895, "eprint_status": "archive", "datestamp": "2023-08-22 11:47:33", "lastmod": "2025-04-23 03:14:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Chen-Shiyou", "name": { "family": "Chen", "given": "Shiyou" } }, { "id": "Coronel-N-C", "name": { "family": "Coronel", "given": "Naomi C." } }, { "id": "Gul-S", "name": { "family": "Gul", "given": "Sheraz" }, "orcid": "0000-0001-8920-8737" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Wang-Lin-Wang", "name": { "family": "Wang", "given": "Lin-Wang" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Bandgap Tunability in Zn(Sn,Ge)N_2 Semiconductor Alloys", "ispublished": "pub", "full_text_status": "public", "keywords": "Zn(Sn,Ge)N_2 semiconductor alloys; miscibility; bandgap", "note": "\u00a9 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: September 5, 2013.\n\nArticle first published online: 5 Dec. 2013.\n\nThis material is based upon work performed by the Joint Center for\nArtificial Photosynthesis, a DOE Energy Innovation Hub, supported\nthrough the Office of Science of the U.S. Department of Energy under\nAward Number DE-SC0004993, and was also supported by the Dow\nChemical Company. P.N. acknowledges support from a National\nScience Foundation Graduate Research Fellowship and from the Resnick\nSustainability Institute. X-ray spectroscopy work was performed at the\nAdvanced Light Source (ALS, BL 10.3.2 and 7.0.1), Berkeley, under\nContract DE-AC02\u201305CH11231. The authors thank Drs. Jinghua Guo\nand Per-Anders Glans-Suzuki for their support at BL 7.0.1.\n\n

Supplemental Material - adma201304473-sup-0001-S1.pdf

", "abstract": "ZnSn_(1-x)Ge_xN_2 direct bandgap semiconductor alloys, with a crystal structure and electronic structure similar to InGaN, are earth-abundant alternatives for efficient, high-quality optoelectronic devices and solar energy conversion. The bandgap is tunable almost monotonically from 2 eV (ZnSnN_2) to 3.1 eV (ZnGeN_2) by control of the Sn/Ge ratio.", "date": "2014-02-26", "date_type": "published", "publication": "Advanced Materials", "volume": "26", "number": "8", "publisher": "Wiley", "pagerange": "1235-1241", "id_number": "CaltechAUTHORS:20131209-100236108", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131209-100236108", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Dow Chemical Company" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1002/adma.201304473", "primary_object": { "basename": "adma201304473-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/a14fd-faw27/files/adma201304473-sup-0001-S1.pdf" }, "pub_year": "2014", "author_list": "Narang, Prineha; Chen, Shiyou; et al." }, { "id": "https://authors.library.caltech.edu/records/etehb-02v25", "eprint_id": 43320, "eprint_status": "archive", "datestamp": "2023-08-19 23:19:38", "lastmod": "2025-04-23 03:13:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Coridan-R-H", "name": { "family": "Coridan", "given": "Robert H." }, "orcid": "0000-0003-1916-4446" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Photoelectrochemistry of core\u2013shell tandem junction n\u2013p^+-Si/n-WO_3 microwire array photoelectrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\nReceived 10 Sep 2013, Accepted 07 Nov 2013;\nFirst published online 16 Dec 2013.\nThis material is based upon work performed by the Joint Center\nfor Artificial Photosynthesis, a DOE Energy Innovation Hub,\nsupported through the Office of Science of the U.S. Department\nof Energy under Award Number DE-SC0004993. M.S. acknowledges\nthe Resnick Sustainability Institute for a graduate\nfellowship. K.F. is supported by the National Science Foundation\nGraduate Research Fellowship under Grant No. DGE-1144469. S.A. acknowledges support from a U.S. Department\nof Energy, Office of Energy Efficiency and Renewable Energy\n(EERE) Postdoctoral Research Award under the EERE Fuel Cell\nTechnologies Program. The authors would like to thank Dr Shu\nHu for assistance in boron doping, Rick Gerhart for fabrication\nof the electrochemical cells used and Dr Andrew Leenheer for\nthe WO3 refractive index data.\n\n

Published - c3ee43048k.pdf

Supplemental Material - c3ee43048k_si.pdf

", "abstract": "Tandem junction (n\u2013p^+-Si/ITO/WO_3/liquid) core\u2013shell microwire devices for solar-driven water splitting have been designed, fabricated and investigated photoelectrochemically. The tandem devices exhibited open-circuit potentials of E_(\u221d) = \u22121.21 V versus E^0\u2032(O_2/H_2O), demonstrating additive voltages across the individual junctions (n\u2013p^+-Si E_(\u221d) = \u22120.5 V versus solution; WO_3/liquid E_(\u221d) = \u22120.73 V versus E^0\u2032(O_2/H_2O)). Optical concentration (12\u00d7, AM1.5D) shifted the open-circuit potential to E_(\u221d) = \u22121.27 V versus E^0\u2032(O_2/H_2O) and resulted in unassisted H_2 production during two-electrode measurements (anode: tandem device, cathode: Pt disc). The solar energy-conversion efficiencies were very low, 0.0068% and 0.0019% when the cathode compartment was saturated with Ar or H_2, respectively, due to the non-optimal photovoltage and band-gap of the WO_3 that was used in the demonstration system to obtain stability of all of the system components under common operating conditions while also insuring product separation for safety purposes.", "date": "2014-02", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "2", "publisher": "Royal Society of Chemistry", "pagerange": "779-790", "id_number": "CaltechAUTHORS:20140110-150648310", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140110-150648310", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C3EE43048K", "primary_object": { "basename": "c3ee43048k.pdf", "url": "https://authors.library.caltech.edu/records/etehb-02v25/files/c3ee43048k.pdf" }, "related_objects": [ { "basename": "c3ee43048k_si.pdf", "url": "https://authors.library.caltech.edu/records/etehb-02v25/files/c3ee43048k_si.pdf" } ], "pub_year": "2014", "author_list": "Shaner, Matthew R.; Fountaine, Katherine T.; et al." }, { "id": "https://authors.library.caltech.edu/records/jsmb4-e5r94", "eprint_id": 43550, "eprint_status": "archive", "datestamp": "2023-08-19 23:17:57", "lastmod": "2023-10-25 23:39:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abrecht-D-G", "name": { "family": "Abrecht", "given": "David G." } }, { "id": "Mu\u00f1oz-J-A", "name": { "family": "Mu\u00f1oz", "given": "Jorge A." } }, { "id": "Smith-Hillary-L", "name": { "family": "Smith", "given": "Hillary L." } }, { "id": "Fultz-B", "name": { "family": "Fultz", "given": "Brent" }, "orcid": "0000-0002-6364-8782" } ] }, "title": "Spin-State Effects on the Thermal Dihydrogen Release from Solid-State [MH(\u03b7^2\u2011H_2)dppe_2]^+ (M = Fe, Ru, Os) Organometallic Complexes for Hydrogen Storage Applications", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: September 30, 2013. Revised: January 2, 2014. \nPublication Date (Web): January 7, 2014. \n\nThe authors wish to thank David Vandervelde of Caltech's liquid NMR facility for his assistance with NMR experiments and Joseph Reiter and Jason Zan at the Jet Propulsion Laboratory in Pasadena, CA for their assistance in planning thermodynamic measurements. Sieverts instrument work was performed at the Jet Propulsion Laboratory, which is operated by the California Institute of Technology under contract with NASA. The Caltech NMR facility is partially supported by the National Institutes of Health through Grant NIH RR027690. ROHF calculations were performed using computational facilities located at the National Energy Research Scientific Computing (NERSC) Center, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. We wish to express gratitude to the Resnick Sustainability Institute for financial support of the project. This work was supported as part of EFree, an Energy Frontier Research Center, under Award No. DE-SG0001057. \n\nThe authors declare no competing financial interest.\n\n

Published - jp409739b.pdf

Supplemental Material - jp409739b_si_001.pdf

", "abstract": "M\u00f6ssbauer spectroscopy, experimental thermodynamic measurements, and computational studies were performed to investigate the properties of molecular hydrogen binding to the organometallic fragments [MHdppe_2]^+ (M = Fe, Ru, Os; dppe =1,2-bis(diphenylphosphino)ethane) to form the dihydrogen complex fragments [MH(\u03b7^2-H_2)dppe_2]^+. M\u00f6ssbauer spectroscopy showed that the dehydrogenated complex [FeHdppe_2]^+ adopts a geometry consistent with the triplet spin state, transitioning to a singlet state complex upon addition of the dihydrogen molecule in a manner similar to the previously studied dinitrogen complexes. From simulations, this spin transition behavior was found to be responsible for the strong binding behavior experimentally observed in the iron complex. Spin-singlet to spin-singlet transitions were found to exhibit thermodynamics consistent with the 5d > 3d > 4d binding trend observed for other transition metal dihydrogen complexes. Finally, the method for distinguishing between dihydrogen and dihydride complexes based on partial quadrupole splittings observed in M\u00f6ssbauer spectra was confirmed, providing a tool for further characterization of these unique species for M\u00f6ssbauer active compounds.", "date": "2014-01-30", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "118", "number": "4", "publisher": "American Chemical Society", "pagerange": "1783-1792", "id_number": "CaltechAUTHORS:20140129-130314711", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140129-130314711", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NIH", "grant_number": "RR027690" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SG0001057" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jp409739b", "pmcid": "PMC3983317", "primary_object": { "basename": "jp409739b_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jsmb4-e5r94/files/jp409739b_si_001.pdf" }, "related_objects": [ { "basename": "jp409739b.pdf", "url": "https://authors.library.caltech.edu/records/jsmb4-e5r94/files/jp409739b.pdf" } ], "pub_year": "2014", "author_list": "Abrecht, David G.; Mu\u00f1oz, Jorge A.; et al." }, { "id": "https://authors.library.caltech.edu/records/zvmaw-85a34", "eprint_id": 43159, "eprint_status": "archive", "datestamp": "2023-08-19 23:11:21", "lastmod": "2023-10-25 23:19:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sveinbj\u00f6rnsson-B-R", "name": { "family": "Sveinbj\u00f6rnsson", "given": "Benjam\u00edn R." } }, { "id": "Miyake-Garret-M", "name": { "family": "Miyake", "given": "Garret M." } }, { "id": "El-Batta-A", "name": { "family": "El-Batta", "given": "Amer" } }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Stereocomplex Formation of Densely Grafted Brush Polymers", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: November 5, 2013; Accepted: December 13, 2013. Publication Date (Web): December 17, 2013. \n\nThis work was supported by the Dow-Resnick Bridge award, GIST, NSF (CHE-1048404) and the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry. The authors would like to thank Professors Eugene Chen and Yuetao Zhang for GPC analysis of the brush random copolymer. Professor Amer El-Batta would like to acknowledge the support provided by King Fahd University of Petroleum and Minerals (KFUPM).\n\n

Supplemental Material - mz400568j_si_001.pdf

", "abstract": "In this report, we explore the capability of macromolecules to interdigitate into densely grafted molecular brush copolymers. We demonstrate that by using the tendency for stereocomplexation between poly(l-lactide) and poly(d-lactide) as a driving force complementary linear polymers and brush copolymers can form a stereocomplex. However, stereocomplex formation between complementary brush copolymers is restricted and only partially observed when the side chains are of a critical molecular weight.", "date": "2014-01-21", "date_type": "published", "publication": "ACS Macro Letters", "volume": "3", "number": "1", "publisher": "American Chemical Society", "pagerange": "26-29", "id_number": "CaltechAUTHORS:20131224-081141144", "issn": "2161-1653", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131224-081141144", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow-Resnick Bridge Award" }, { "agency": "GIST" }, { "agency": "NSF", "grant_number": "CHE-1048404" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "King Fahd University of Petroleum and Minerals (KFUPM)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/mz400568j", "primary_object": { "basename": "mz400568j_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zvmaw-85a34/files/mz400568j_si_001.pdf" }, "pub_year": "2014", "author_list": "Sveinbj\u00f6rnsson, Benjam\u00edn R.; Miyake, Garret M.; et al." }, { "id": "https://authors.library.caltech.edu/records/mh71n-8b306", "eprint_id": 41845, "eprint_status": "archive", "datestamp": "2023-08-19 23:07:12", "lastmod": "2025-04-23 03:12:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Shiyou", "name": { "family": "Chen", "given": "Shiyou" } }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Wang-Lin-Wang", "name": { "family": "Wang", "given": "Lin-Wang" } } ] }, "title": "Phase Stability and Defect Physics of a Ternary ZnSnN_2 Semiconductor: First Principles Insights", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 WILEY-VCH Verlag.\n\nReceived: June 14, 2013\nRevised: July 24, 2013\nPublished online: October 8, 2013\n\nThis material is based upon work performed by the Joint Center for\nArtificial Photosynthesis, a DOE Energy Innovation Hub, supported\nthrough the Office of Science of the U.S. Department of Energy under\nAward Number DE-SC0004993. Prineha Narang is supported by the\nNational Science Foundation Graduate Research Fellowship and the\nResnick Sustainability Institute.", "abstract": "Direct bandgap, earth abundant semiconductors with Eg\naround 1.5 eV are essential for both photovoltaic and solar to\nfuel (photocatalytic) energy conversion. Among the conventional\nsemiconductors, such as element Si and Ge, binary III-V\n(III = B, Al, Ga, In; V = N, P, As, Sb) and II-VI (II = Zn, Cd;\nVI = O, S, Se, Te), only a limited number of candidates have\nsuitable bandgaps in the range 1.0\u20132.0 eV. This motivates the\nsearch for earth-abundant alternatives to current semiconductors\nfor efficient, high-quality optoelectronic devices, photovoltaics\nand photocatalytic energy conversion. One methodology\nfor the search is to study ternary and multi-ternary semiconductors\nwith more elements and more flexible optoelectronic\nproperties.", "date": "2014-01-15", "date_type": "published", "publication": "Advanced Materials", "volume": "26", "number": "2", "publisher": "Wiley", "pagerange": "311-315", "id_number": "CaltechAUTHORS:20131009-164328252", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131009-164328252", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1002/adma.201302727", "pub_year": "2014", "author_list": "Chen, Shiyou; Narang, Prineha; et al." }, { "id": "https://authors.library.caltech.edu/records/q5j5w-8vs63", "eprint_id": 43475, "eprint_status": "archive", "datestamp": "2023-08-22 11:26:50", "lastmod": "2023-10-25 23:34:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yiyang", "name": { "family": "Liu", "given": "Yiyang" } }, { "id": "Kim-Kelly-E", "name": { "family": "Kim", "given": "Kelly E." } }, { "id": "Herbert-M-B", "name": { "family": "Herbert", "given": "Myles B." } }, { "id": "Fedorov-Alexey", "name": { "family": "Fedorov", "given": "Alexey" }, "orcid": "0000-0001-9814-6726" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" } ] }, "title": "Palladium-Catalyzed Decarbonylative Dehydration of Fatty Acids for the Production of Linear Alpha Olefins", "ispublished": "pub", "full_text_status": "public", "keywords": "decarbonylative dehydration; fatty acids; large-scale process; linear alpha olefins; palladium; renewable feedstocks; Z-selective metathesis", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. \n\nReceived: December 9, 2013; Published online: January 13, 2014. \n\nThe authors wish to thank the Resnick Sustainability Institute at Caltech (graduate fellowship to Y.L.), BP (postdoctoral fellowship to A.F. under the XC2 program), NIH-NIGMS (R01GM080269, B.M.S.), NIH (NIH 5R01GM031332-27, R.H.G.), the Gordon and Betty Moore Foundation, the Caltech Center for Catalysis and Chemical Synthesis, and Caltech for financial support. Materia, Inc. is thanked for the generous donation of ruthenium catalysts. Dr. David Vander-Velde is acknowledged for NMR spectroscopy assistance. Dr. Mona Shahgholi and Naseem Torian are acknowledged for high-resolution mass spectrometry assistance. Dr. Scott Virgil is acknowledged for helpful discussions.\n\n

Accepted Version - nihms-565526.pdf

Supplemental Material - adsc_201301109_sm_miscellaneous_information.pdf

", "abstract": "A highly efficient palladium-catalyzed decarbonylative dehydration reaction of carboxylic acids is reported. This method transforms abundant and renewable even-numbered natural fatty acids into valuable and expensive odd-numbered alpha olefins. Additionally, the chemistry displays a high functional group tolerance. The process employs a low loading of palladium catalyst and proceeds under solvent-free and relatively mild conditions.", "date": "2014-01-13", "date_type": "published", "publication": "Advanced Synthesis and Catalysis", "volume": "356", "number": "1", "publisher": "Wiley", "pagerange": "130-136", "id_number": "CaltechAUTHORS:20140122-135551444", "issn": "1615-4150", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140122-135551444", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "BP XC2 Program" }, { "agency": "NIH", "grant_number": "R01GM080269" }, { "agency": "NIH", "grant_number": "5R01GM031332-27" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Caltech Center for Catalysis and Chemical Synthesis" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "pmcid": "PMC3998208", "primary_object": { "basename": "nihms-565526.pdf", "url": "https://authors.library.caltech.edu/records/q5j5w-8vs63/files/nihms-565526.pdf" }, "related_objects": [ { "basename": "adsc_201301109_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/q5j5w-8vs63/files/adsc_201301109_sm_miscellaneous_information.pdf" } ], "pub_year": "2014", "author_list": "Liu, Yiyang; Kim, Kelly E.; et al." }, { "id": "https://authors.library.caltech.edu/records/yn74z-hm053", "eprint_id": 43327, "eprint_status": "archive", "datestamp": "2023-08-19 22:40:10", "lastmod": "2023-10-25 23:28:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Webb-M-A", "name": { "family": "Webb", "given": "Michael A." }, "orcid": "0000-0002-7420-4474" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Position-Specific and Clumped Stable Isotope Studies: Comparison of the Urey and Path-Integral Approaches for Carbon Dioxide, Nitrous Oxide, Methane, and Propane", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society.\nReceived: November 12, 2013;\nRevised: December 20, 2013;\nPublication Date (Web): December 27, 2013.\nThis research was supported by the Resnick Sustainability\nInstitute and the Department of Energy (DE-SC0006598). We\nacknowledge computing resources from the National Energy\nResearch Scientific Computing Center (DE-AC02-05CH11231)\nand a Director's Discretionary Allocation from the Argonne\nLeadership Computing Facility. We thank Jos\u00e9 Z\u00fa\u00f1iga and Tim\nLee for providing information and subroutines for their potential\nenergy surfaces. We also thank John Eiler, Alex Sessions, and\nAdam Subhas for helpful discussions.\n\n

Supplemental Material - jp411134v_si_001.pdf

", "abstract": "We combine path-integral Monte Carlo methods with high-quality potential energy surfaces to compute equilibrium isotope effects in a variety of systems relevant to 'clumped' isotope analysis and isotope geochemistry, including CO_2, N_2O, methane, and propane. Through a systematic study of heavy-atom isotope-exchange reactions, we quantify and analyze errors that arise in the widely used Urey model for predicting equilibrium constants of isotope-exchange reactions using reduced partition function ratios. These results illustrate that the Urey model relies on a nontrivial cancellation of errors that can shift the apparent equilibrium temperature by as much as 35 K for a given distribution of isotopologues. The calculations reported here provide the same level of precision as the best existing analytical instrumentation, resolving the relative enrichment of certain isotopologues to as little as 0.01\u2030. These findings demonstrate path-integral methods to be a rigorous and viable alternative to more approximate methods for heavy-atom geochemical applications.", "date": "2013-12-27", "date_type": "published", "publication": "Journal of Physical Chemistry A", "publisher": "American Chemical Society", "id_number": "CaltechAUTHORS:20140113-090540183", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140113-090540183", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006598" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Argonne Leadership Computing Facility" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jp411134v", "primary_object": { "basename": "jp411134v_si_001.pdf", "url": "https://authors.library.caltech.edu/records/yn74z-hm053/files/jp411134v_si_001.pdf" }, "pub_year": "2013", "author_list": "Webb, Michael A. and Miller, Thomas F., III" }, { "id": "https://authors.library.caltech.edu/records/a8kma-pba33", "eprint_id": 43592, "eprint_status": "archive", "datestamp": "2023-08-19 22:39:42", "lastmod": "2023-10-25 23:41:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Herbert-D-E", "name": { "family": "Herbert", "given": "David E." } }, { "id": "Lionetti-D", "name": { "family": "Lionetti", "given": "Davide" }, "orcid": "0000-0002-4937-886X" }, { "id": "Rittle-J", "name": { "family": "Rittle", "given": "Jonathan" } }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Heterometallic Triiron-Oxo/Hydroxo Clusters: Effect of Redox-Inactive Metals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society.\n\nPublished In Issue December 26, 2013; Article ASAP December 16, 2013; Just Accepted Manuscript December 04, 2013; Received: October 13, 2013.\n\nThe authors declare no competing financial interest.\n\nThis work was supported by the California Institute of\nTechnology, the Searle Scholars Program, the NSF CAREER\nCHE-1151918 (T.A.), a Camille & Henry Dreyfus Environmental\nChemistry Fellowship (D.E.H.), and a Resnick\nSustainability Institute graduate fellowship (D.L.). T.A. is a\nSloan and Cottrell Fellow. We thank Larry M. Henling and Dr.\nMichael Takase for assistance with crystallography and Prof.\nJonas C. Peters for use of a M\u00f6ssbauer spectrometer. Collection\nof M\u00f6ssbauer data was made possible by use of an instrument\npurchased with funds from the National Science Foundation\nCenter for Chemical Innovation on Solar Fuels (CCI Solar,\nGrant CHE-1305124). The Bruker KAPPA APEXII X-ray\ndiffractometer was purchased via an NSF Chemistry Research\nInstrumentation award to Caltech (CHE-0639094). We\nacknowledge the Gordon and Betty Moore Foundation, the\nBeckman Institute, and the Sanofi-Aventis BRP at Caltech for\ntheir generous support of the Molecular Observatory at Caltech.\nOperations at SSRL are supported by the U.S. DOE and NIH.\n\n

Accepted Version - nihms550402.pdf

Supplemental Material - ja4104974_si_001.pdf

Supplemental Material - ja4104974_si_002.zip

", "abstract": "A series of tetranuclear oxo/hydroxo clusters comprised of three Fe centers and a redox-inactive metal (M) of various charge is reported. Crystallographic\nstudies show an unprecedented Fe_3M(\u03bc_4-O)(\u03bc_2-OH) core\nthat remains intact upon changing M or the oxidation state\nof iron. Electrochemical studies reveal that the reduction\npotentials (E_(1/2)) span a window of 500 mV and depend\nupon the Lewis acidity of M. Using the pK_a of the M-aqua\ncomplex as a measure of Lewis acidity, these compounds\ndisplay a linear dependence between E1/2 and acidity, with\na slope of \u223c70 mV per pK_a unit. The current study of\n[Fe_3MO(OH)] and previous ones of [Mn_3MO_n] (n = 2,4)\nmoieties support the generality of the above relationship\nbetween the reduction potentials of heterometallic oxido\nclusters and the Lewis acidity of incorporated cations, as\napplied to clusters of different redox-active metals.", "date": "2013-12-26", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "135", "number": "51", "publisher": "American Chemical Society", "pagerange": "19075-19078", "id_number": "CaltechAUTHORS:20140130-144616034", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140130-144616034", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Searle Scholars Program" }, { "agency": "NSF", "grant_number": "CHE-1151918" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-0639094" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" } ] }, "doi": "10.1021/ja4104974", "pmcid": "PMC3953215", "primary_object": { "basename": "ja4104974_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a8kma-pba33/files/ja4104974_si_001.pdf" }, "related_objects": [ { "basename": "ja4104974_si_002.zip", "url": "https://authors.library.caltech.edu/records/a8kma-pba33/files/ja4104974_si_002.zip" }, { "basename": "nihms550402.pdf", "url": "https://authors.library.caltech.edu/records/a8kma-pba33/files/nihms550402.pdf" } ], "pub_year": "2013", "author_list": "Herbert, David E.; Lionetti, Davide; et al." }, { "id": "https://authors.library.caltech.edu/records/j63v0-pyb40", "eprint_id": 41911, "eprint_status": "archive", "datestamp": "2023-08-19 22:19:17", "lastmod": "2023-10-25 14:54:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Smith-M-A", "name": { "family": "Smith", "given": "Matthew A." } }, { "id": "Bedbrook-C-N", "name": { "family": "Bedbrook", "given": "Claire N." }, "orcid": "0000-0003-3973-598X" }, { "id": "Wu-Timothy", "name": { "family": "Wu", "given": "Timothy" } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Hypocrea jecorina Cellobiohydrolase I Stabilizing Mutations Identified Using Noncontiguous Recombination", "ispublished": "pub", "full_text_status": "public", "keywords": "CBHI, Cel7A, cellulase, protein recombination, thermostability", "note": "\u00a9 2013 American Chemical Society.\n\nJust Accepted Manuscript May 20, 2013, Received: February 14, 2013.\n\nPublished: May 20, 2013.\nThe authors thank John McIntosh and Mary Farrow for useful\ndiscussions in the preparation of this manuscript. This work\nwas supported by the Institute for Collaborative Biotechnologies\nthrough a grant [W911NF-09-D-0001] from the U.S.\nArmy Research and The National Central University, Taiwan,\nthough a Cooperative Agreement for Energy Research\nCollaboration. M.A.S. is supported by a Resnick Sustainability\nInstitute fellowship.\n\n

Supplemental Material - sb400010m_si_001.pdf

", "abstract": "Noncontiguous recombination (NCR) is a\nmethod to identify pieces of structure that can be swapped\namong homologous proteins to create new, chimeric proteins.\nThese \"blocks\" are encoded by elements of sequence that are\nnot necessarily contiguous along the polypeptide chain. We\nused NCR to design a library in which blocks of structure from\nHypocrea jecorina cellobiohydrolase I (Cel7A) and its two\nthermostable homologues from Talaromyces emersonii and\nChaetomium thermophilum are shuffled to create 531,438\npossible chimeric enzymes. We constructed a maximally\ninformative subset of 35 chimeras to analyze this library and\nfound that the blocks contribute additively to the stability of a\nchimera. Within two highly stabilizing blocks, we uncovered six single amino acid substitutions that each improve the stability of\nH. jecorina cellobiohydrolase I by 1\u22123 \u00b0C. The small number of measurements required to find these mutations demonstrates\nthat noncontiguous recombination is an efficient strategy for identifying stabilizing mutations.", "date": "2013-12", "date_type": "published", "publication": "ACS Synthetic Biology", "volume": "2", "number": "12", "publisher": "American Chemical Society", "pagerange": "690-696", "id_number": "CaltechAUTHORS:20131015-082946657", "issn": "2161-5063", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131015-082946657", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-09-0001" }, { "agency": "National Central University (Taiwan)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/sb400010m", "primary_object": { "basename": "sb400010m_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j63v0-pyb40/files/sb400010m_si_001.pdf" }, "pub_year": "2013", "author_list": "Smith, Matthew A.; Bedbrook, Claire N.; et al." }, { "id": "https://authors.library.caltech.edu/records/ywezm-eqr97", "eprint_id": 42138, "eprint_status": "archive", "datestamp": "2023-08-19 22:19:26", "lastmod": "2023-10-25 15:41:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trudeau-D-L", "name": { "family": "Trudeau", "given": "Devin L." } }, { "id": "Smith-M-A", "name": { "family": "Smith", "given": "Matthew A." } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Innovation by homologous recombination", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 Elsevier Ltd. \nAvailable online 29 October 2013.\n\nThe authors thank Claire Bedbrook for helpful discussions. This work was supported by the Institute for Collaborative Biotechnologies through grant [W911NF-09-D-0001] from the U.S. Army Research and and the National Science Council of Taiwan, R.O.C., through its grant no. NSC 102-3113-P-008-001. DLT is supported by a Canadian National Science and Engineering Research Council post-graduate fellowship. MAS was supported by a Resnick Sustainability Institute fellowship.", "abstract": "Swapping fragments among protein homologs can produce chimeric proteins with a wide range of properties, including properties not exhibited by the parents. Computational methods that use information from structures and sequence alignments have been used to design highly functional chimeras and chimera libraries. Recombination has generated proteins with diverse thermostability and mechanical stability, enzyme substrate specificity, and optogenetic properties. Linear regression, Gaussian processes, and support vector machine learning have been used to model sequence-function relationships and predict useful chimeras. These approaches enable engineering of protein chimeras with desired functions, as well as elucidation of the structural basis for these functions.", "date": "2013-12", "date_type": "published", "publication": "Current Opinion in Chemical Biology", "volume": "17", "number": "6", "publisher": "Elsevier", "pagerange": "902-909", "id_number": "CaltechAUTHORS:20131030-110816201", "issn": "1367-5931", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131030-110816201", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911 NF-09-D-001" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 102-3113-P-008-001" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.cbpa.2013.10.007", "pub_year": "2013", "author_list": "Trudeau, Devin L.; Smith, Matthew A.; et al." }, { "id": "https://authors.library.caltech.edu/records/y6v12-wym60", "eprint_id": 42568, "eprint_status": "archive", "datestamp": "2023-08-19 22:15:14", "lastmod": "2023-10-25 16:47:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Day-T-W", "name": { "family": "Day", "given": "Tristan" } }, { "id": "Borup-K-A", "name": { "family": "Borup", "given": "Kasper A." } }, { "id": "Christensen-S", "name": { "family": "Christensen", "given": "Sebastian" } }, { "id": "Iversen-B-B", "name": { "family": "Iversen", "given": "Bo B." } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Phase transition enhanced thermoelectric figure-of-merit in copper chalcogenides", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. \n\nReceived 16 August 2013 Accepted 17 October 2013 Published online 14 November 2013.\n\nThe authors would like to acknowledge Huili Liu, Dr. Xun Shi and Dr. Lidong Chen of SIC-CAS for discussions and assistance with heat capacity measurements; Alex Z. Williams and the NASA-JPL for aid in measuring the Hall coefficient; and Resnick Institute and Air Force Office of Science Research for support. Use of the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.\n\n

Published - APL_Materials.pdf

", "abstract": "While thermoelectric materials can be used for solid state cooling, waste heat recovery, and solar electricity generation, low values of the thermoelectric figure of merit, zT, have led to an efficiency too low for widespread use. Thermoelectric effects are characterized by the Seebeck coefficient or thermopower, which is related to the entropy associated with charge transport. For example, coupling spin entropy with the presence of charge carriers has enabled the enhancement of zT in cobalt oxides. We demonstrate that the coupling of a continuous phase transition to carrier transport in Cu 2Se over a broad (360\u2013410 K) temperature range results in a dramatic peak in thermopower, an increase in phonon and electron scattering, and a corresponding doubling of zT (to 0.7 at 406 K), and a similar but larger increase over a wider temperature range in the zT of Cu 1.97 Ag .03Se (almost 1.0 at 400 K). The use of structural entropy for enhanced thermopower could lead to new engineering approaches for thermoelectric materials with high zT and new green applications for thermoelectrics.", "date": "2013-11-14", "date_type": "published", "publication": "APL Materials", "volume": "1", "number": "5", "publisher": "American Institute of Physics", "pagerange": "052107", "id_number": "CaltechAUTHORS:20131119-110722220", "issn": "2166-532X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131119-110722220", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.4827595", "primary_object": { "basename": "APL_Materials.pdf", "url": "https://authors.library.caltech.edu/records/y6v12-wym60/files/APL_Materials.pdf" }, "pub_year": "2013", "author_list": "Brown, David R.; Day, Tristan; et al." }, { "id": "https://authors.library.caltech.edu/records/f7zpf-jat38", "eprint_id": 42140, "eprint_status": "archive", "datestamp": "2023-08-19 22:14:30", "lastmod": "2025-04-23 15:18:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Weitekamp-R-A", "name": { "family": "Weitekamp", "given": "Raymond A." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Photolithographic Olefin Metathesis Polymerization", "ispublished": "pub", "full_text_status": "public", "keywords": "radiation chemistry, photochemistry, retrographic processes", "note": "Copyright \u00a9 2013 American Chemical Society. \n\nReceived September 9, 2013. Publication Date (Web): October 30, 2013. \n\nThis work is part of the Light-Material Interactions in Energy Conversion Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001293. This research was conducted with Government support under and awarded by DoD, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship, 32 CFR 168a, awarded to R.A.W. Profilometry was performed at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. R.A.W. thanks the Resnick Sustainability Institute for a\ngraduate fellowship, and Jim Fakonas for many helpful discussions.\n\n

Supplemental Material - ja4093083_si_001.pdf

", "abstract": "Patterning functional materials is a central challenge across many fields of science. The ability to lithographically fabricate micro- and nanostructures has been one of the most impactful technological breakthroughs of the last century. In part due to the complexity of the chemical processes in photoresists, there is a limited variety of materials that can currently be patterned by photolithography. We report a negative tone photoresist using a photoactivated olefin metathesis catalyst, which can be quickly prepared in a one-pot synthesis from commercially available starting materials. The resist is based on a ruthenium vinyl ether complex, widely regarded as inactive toward olefin metathesis. The combination of this photoactivated catalyst with the fidelity and functional group tolerance of ruthenium-mediated olefin metathesis enables a host of new possibilities for photopatterned materials.", "date": "2013-11-13", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "135", "number": "45", "publisher": "American Chemical Society", "pagerange": "16817-16820", "id_number": "CaltechAUTHORS:20131030-112906993", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131030-112906993", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship", "grant_number": "32 CFR 168a" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/ja4093083", "primary_object": { "basename": "ja4093083_si_001.pdf", "url": "https://authors.library.caltech.edu/records/f7zpf-jat38/files/ja4093083_si_001.pdf" }, "pub_year": "2013", "author_list": "Weitekamp, Raymond A.; Atwater, Harry A.; et al." }, { "id": "https://authors.library.caltech.edu/records/ma2gs-ehq74", "eprint_id": 42793, "eprint_status": "archive", "datestamp": "2023-08-22 10:49:44", "lastmod": "2023-10-25 23:01:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Diallo-M-S", "name": { "family": "Diallo", "given": "Mamadou S." }, "orcid": "0000-0002-2571-1568" }, { "id": "Fromer-N-A", "name": { "family": "Fromer", "given": "Neil A." } }, { "id": "Jhon-M-S", "name": { "family": "Jhon", "given": "Myung S." } } ] }, "title": "Nanotechnology for sustainable development: retrospective and outlook", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Nanotechnology; Sustainability; Natural resources; Manufacturing; Societal needs", "note": "\u00a9 2013 Springer Science+Business Media Dordrecht.\nReceived: 17 July 2013; Accepted: 3 October 2013; Published online: 1 November 2013.\n\nThe edition of this JNR special issue on\n''Nanotechnology for Sustainable Development'' was a timely\neffort in an area where exciting breakthroughs are occurring and\nparadigm shifting technologies are being developed. As Guest\nEditors, we really enjoyed working on this JNR special issue. We\nthank the authors and reviewers for making the edition of this\nissue possible through their responsiveness and high quality\nwork. We thank Dr. Mihail Roco (NSF Senior Advisor for\nNanotechnology and Editor-in-Chief of JNR) and the JNR staff\nfor their constant support throughout the edition of this special\nissue. We greatly appreciate Dr. Roco's leadership in bringing\nsustainable development to the forefront of the nanotechnology\nresearch agenda worldwide. We thank the National\nNanotechnology Policy Center (NNPC) of the Korea Institute\nof Science and Technology Information (KISTI) of the Republic\nof Korea and the Resnick Sustainability Institute of the\nCalifornia Institute of Technology for their financial support to\nthe printing of a hardbound book of this JNR special issue.\nMamadou Diallo thanks the KAIST EEWS Initiative (Grant #\nNT080607C0209721), the National Research Foundation of\nKorea (NRF) [MEST grant No. 2012M1A2A2026588] and the\nUS National Science Foundation (NSF) (CBET Grants 0948485\nand 0506951) for funding his research on sustainable chemistry,\nengineering and materials (SusCHEM). Neil Fromer thanks the\nResnick Sustainability Institute, as well as the LMI-EFRC, Rod\nEggert, and Jack Lifton and the other attendees of the Resnick\nInstitute critical materials workshop for helpful discussions.\nMyung Jhon's research was partially supported by the Korea\nScience & Engineering Foundation through the WCU Project.", "abstract": "The world is facing great challenges in meeting rising demands for basic commodities (e.g., food, water and energy), finished goods (e.g., cell phones, cars and airplanes) and services (e.g., shelter, healthcare and employment) while reducing and minimizing the impact of human activities on Earth's global environment and climate. Nanotechnology has emerged as a versatile platform that could provide efficient, cost-effective and environmentally acceptable solutions to the global sustainability challenges facing society. This special issue of the Journal of Nanoparticle Research is devoted to the utilization of nanotechnology to improve or achieve sustainable development. We highlight recent advances and discuss opportunities of utilizing nanotechnology to address global challenges in (1) water purification, (2) clean energy technologies, (3) greenhouse gases management, (4) materials supply and utilization, and (5) green manufacturing and chemistry. In addition to the technical challenges listed above, we also discuss societal perspectives and provide an outlook of the role of nanotechnology in the convergence of knowledge, technology and society for achieving sustainable development.", "date": "2013-11-01", "date_type": "published", "publication": "Journal of Nanoparticle Research", "volume": "15", "number": "11", "publisher": "Springer", "pagerange": "Art. No. 2044", "id_number": "CaltechAUTHORS:20131203-101122623", "issn": "1388-0764", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131203-101122623", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Korea Institute of Science and Technology Information (KISTI)" }, { "agency": "National Nanotechnology Policy Center (NNPC)" }, { "agency": "Caltech Resnick Sustainability Institute" }, { "agency": "KAIST EEWS Initiative", "grant_number": "NT080607C0209721" }, { "agency": "National Research Foundation of Korea (NRF) Ministry of Education, Science and Technology (MEST)", "grant_number": "2012M1A2A2026588" }, { "agency": "NSF CBET", "grant_number": "0948485" }, { "agency": "NSF CBET", "grant_number": "0506951" }, { "agency": "Korea Science & Engineering Foundation WCU Project" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s11051-013-2044-0", "pub_year": "2013", "author_list": "Diallo, Mamadou S.; Fromer, Neil A.; et al." }, { "id": "https://authors.library.caltech.edu/records/r68eb-k0712", "eprint_id": 42998, "eprint_status": "archive", "datestamp": "2023-08-22 10:44:31", "lastmod": "2023-10-25 23:11:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cai-Desmond-W-H", "name": { "family": "Cai", "given": "Desmond W. H." }, "orcid": "0000-0001-9207-1890" }, { "id": "Adlakha-S", "name": { "family": "Adlakha", "given": "Sachin" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" }, { "id": "De-Martini-P", "name": { "family": "De Martini", "given": "Paul" } }, { "id": "Chandy-K-M", "name": { "family": "Chandy", "given": "K. Mani" } } ] }, "title": "Impact of residential PV adoption on Retail Electricity Rates", "ispublished": "pub", "full_text_status": "restricted", "keywords": "PV adoption; Distributed energy adoption; Electricity rate spiral", "note": "\u00a9 2013 Elsevier Ltd. Received 27 November 2012. Accepted 2 July 2013. Available online 3 August 2013. We thank Prof. Adam Wierman, Prof. John Ledyard, and Dr. Julian Bunn of Caltech, Leonardo Von Prellwitz of Cisco, Jeff Gooding, Robert Sherick, Russell Garwac, Andre Ramirez, Sunil Shah, Lynda Ziegler, Paula Campbell, Gregg Ander, Carlos Haiad, Juan Menedex, Scott Mitchell, and Devin Rauss of SCE, Lena Hansen of Rocky Mountain Institute (RMI), Tom McDaniel, Jack Peurach, and Carl Lenox of SunPower, Hung-po Chao of NEISO, George Lee, and Neil Fromer of Caltech for helpful comments and input. This work was supported by NSF NetSE Grant CNS 0911041, ARPA-E Grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan, R.O.C, Grant NSC 101-3113-P-008-001, Resnick Institute, and Okawa Foundation.", "abstract": "The price of electricity supplied from home rooftop photo voltaic (PV) solar cells has fallen below the retail price of grid electricity in some areas. A number of residential households have an economic incentive to install rooftop PV systems and reduce their purchases of electricity from the grid. A significant portion of the costs incurred by utility companies are fixed costs which must be recovered even as consumption falls. Electricity rates must increase in order for utility companies to recover fixed costs from shrinking sales bases. Increasing rates will, in turn, result in even more economic incentives for customers to adopt rooftop PV. In this paper, we model this feedback between PV adoption and electricity rates and study its impact on future PV penetration and net-metering costs. We find that the most important parameter that determines whether this feedback has an effect is the fraction of customers who adopt PV in any year based solely on the money saved by doing so in that year, independent of the uncertainties of future years. These uncertainties include possible changes in rate structures such as the introduction of connection charges, the possibility of PV prices dropping significantly in the future, possible changes in tax incentives, and confidence in the reliability and maintainability of PV.", "date": "2013-11", "date_type": "published", "publication": "Energy Policy", "volume": "62", "publisher": "Elsevier", "pagerange": "830-843", "id_number": "CaltechAUTHORS:20131213-111904382", "issn": "0301-4215", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131213-111904382", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF NetSE", "grant_number": "CNS-0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 101-3113-P-008-001" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Okawa Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.enpol.2013.07.009", "pub_year": "2013", "author_list": "Cai, Desmond W. H.; Adlakha, Sachin; et al." }, { "id": "https://authors.library.caltech.edu/records/x3nb5-9a672", "eprint_id": 43212, "eprint_status": "archive", "datestamp": "2023-08-22 10:45:04", "lastmod": "2023-10-25 23:22:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hong-Sung-Woo", "name": { "family": "Hong", "given": "Sung Woo" } }, { "id": "Gu-Weiyin", "name": { "family": "Gu", "given": "Weiyin" } }, { "id": "Huh-June", "name": { "family": "Huh", "given": "June" } }, { "id": "Sveinbjornsson-B-R", "name": { "family": "Sveinbjornsson", "given": "Benjamin R." } }, { "id": "Jeong-Gajin", "name": { "family": "Jeong", "given": "Gajin" } }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert Howard" }, "orcid": "0000-0002-0057-7817" }, { "id": "Russell-T-P", "name": { "family": "Russell", "given": "Thomas P." } } ] }, "title": "On the Self-Assembly of Brush Block Copolymers in Thin Films", "ispublished": "pub", "full_text_status": "public", "keywords": "brush polymers; solvent-annealing; self-assembly; periodic nanopatterns; large feature sizes", "note": "\u00a9 2013 American Chemical Society. \n\nReceived for review May 24, 2013 and accepted October 24, 2013. \nPublished online October 24, 2013. \n\nThis work was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences under contract DEFG02-96ER45612 (SWH, WG and GJ were partially supported through DEFG02-96ER45612 and performed the samples preparation and x-ray scattering measurements under the guidance of TPR). BRS, supported by the Dow-Resnick Bridge award and the NSF (CHE-1048404), performed the synthesis of the materials under the guidance of RHG. JH, supported through Samsung Display, performed the theoretical calculations. We thank D. H. Lee and X. Gu for assistance with the GI-SAXS and GI-WAXS measurements; we thank W. Zhao for assistance with the TEM measurements. We thank Y. Xia for useful discussions on the synthesis of the brush BCPs. Use of the Advanced Light Source at the Lawrence Berkeley National Laboratory is acknowledged. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, Material Science Division of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231 at Lawrence Berkeley National Laboratory.\n\n

Supplemental Material - nn402639g_si_001.pdf

", "abstract": "We describe a simple route to fabricate two dimensionally well-ordered, periodic nanopatterns using the self-assembly of brush block copolymers (brush BCPs). Well-developed lamellar microdomains oriented perpendicular to the substrate are achieved, without modification of the underlying substrates, and structures with feature sizes greater than 200 nm are generated due to the reduced degree of chain entanglements of brush BCPs. A near-perfect linear scaling law was found for the period, L, as a function of backbone degree of polymerization (DP) for two series of brush BCPs. The exponent increases slightly from 0.99 to 1.03 as the side chain molecular weight increases from 2.4 to 4.5 kg/mol^(\u20131) and saturated with further increase in the side chain molecular weight due to the entropic penalty associated with the packing of the side chains. Porous templates and scaffolds from brush BCP thin films are also obtained by selective etching of one component.", "date": "2013-11", "date_type": "published", "publication": "ACS Nano", "volume": "7", "number": "11", "publisher": "American Chemical Society", "pagerange": "9684-9692", "id_number": "CaltechAUTHORS:20140106-083231491", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140106-083231491", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-96ER45612" }, { "agency": "Dow-Resnick Bridge Award" }, { "agency": "NSF", "grant_number": "CHE-1048404" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Samsung Display" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/nn402639g", "primary_object": { "basename": "nn402639g_si_001.pdf", "url": "https://authors.library.caltech.edu/records/x3nb5-9a672/files/nn402639g_si_001.pdf" }, "pub_year": "2013", "author_list": "Hong, Sung Woo; Gu, Weiyin; et al." }, { "id": "https://authors.library.caltech.edu/records/wdh99-fkz82", "eprint_id": 42790, "eprint_status": "archive", "datestamp": "2023-08-19 22:03:52", "lastmod": "2023-10-25 23:01:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Changhong", "name": { "family": "Zhao", "given": "Changhong" }, "orcid": "0000-0003-0539-8591" }, { "id": "Topcu-U", "name": { "family": "Topcu", "given": "Ufuk" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Optimal Load Control via Frequency Measurement and Neighborhood Area Communication", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Distributed control, frequency responsive load, neighborhood area communication, optimization", "note": "\u00a9 2013 IEEE. Manuscript received April 05, 2012; revised September 08, 2012, January 07, 2013, and March 27, 2013; accepted April 25, 2013. Date of publication May 14, 2013; date of current version October 17, 2013. This work was supported by NSF NetSE grant CNS 0911041, NSF grant CNS 1312390, ARPA-E grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan, R.O.C. grant, NSC 101-3113-P-008-001, Resnick Institute, and Okawa\nFoundation. Paper no. TPWRS-00336-2012.", "abstract": "We propose a decentralized optimal load control scheme that provides contingency reserve in the presence of sudden generation drop. The scheme takes advantage of flexibility of frequency responsive loads and neighborhood area communication to solve an optimal load control problem that balances load and generation while minimizing end-use disutility of participating in load control. Local frequency measurements enable individual loads to estimate the total mismatch between load and generation. Neighborhood area communication helps mitigate effects of inconsistencies in the local estimates due to frequency measurement noise. Case studies show that the proposed scheme can balance load with generation and restore the frequency within seconds of time after a generation drop, even when the loads use a highly simplified power system model in their algorithms. We also investigate tradeoffs between the amount of communication and the performance of the proposed scheme through simulation-based experiments.", "date": "2013-11", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "28", "number": "4", "publisher": "IEEE", "pagerange": "3576-3587", "id_number": "CaltechAUTHORS:20131203-091918486", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131203-091918486", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF NetSE", "grant_number": "CNS-0911041" }, { "agency": "NSF", "grant_number": "CNS-1312390" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 101-3113-P-008-001" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Okawa Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2013.2261096", "pub_year": "2013", "author_list": "Zhao, Changhong; Topcu, Ufuk; et al." }, { "id": "https://authors.library.caltech.edu/records/w8xrw-r8417", "eprint_id": 42241, "eprint_status": "archive", "datestamp": "2023-08-19 21:53:17", "lastmod": "2023-10-25 15:46:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fromer-N-A", "name": { "family": "Fromer", "given": "Neil A." } }, { "id": "Diallo-M-S", "name": { "family": "Diallo", "given": "Mamadou S." }, "orcid": "0000-0002-2571-1568" } ] }, "title": "Nanotechnology and clean energy: sustainable utilization\n and supply of critical materials", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Critical materials, Clean energy, Nanotechnology, Urban mining", "note": "\u00a9 2013 Springer Science+Business Media Dordrecht. Received: 20 June 2013. Accepted: 13 September 2013. Neil A. Fromer thanks the Resnick Sustainability Institute, as well as the LMI-EFRC, Rod Eggert, and Jack Lifton and the other attendees of the Resnick Institute critical materials workshop for helpful discussions. Mamadou Diallo thanks the EEWS Initiative (Grant #NT080607C0209721), the National Research Foundation of Korea (NRF) [MEST grant No. 2012M1A2A2026588] and the National Science Foundation (NSF) of United States [CBET grants 0948485 and 0506951] for funding his research on\nsustainable chemistry, engineering and materials (SusChEM).", "abstract": "Advances in nanoscale science and engineering suggest that many of the current problems involving the sustainable utilization and supply of critical materials in clean and renewable energy technologies could be addressed using (i) nanostructured materials with enhanced electronic, optical, magnetic and catalytic properties and (ii) nanotechnology-based separation materials and systems that can recover critical materials from non-traditional sources including mine tailings, industrial wastewater and electronic wastes with minimum environmental impact. This article discusses the utilization of nanotechnology to improve or achieve materials sustainability for energy generation, conversion and storage. We highlight recent advances and discuss opportunities of utilizing nanotechnology to address materials sustainability for clean and renewable energy technologies.", "date": "2013-10-10", "date_type": "published", "publication": "Journal of Nanoparticle Research", "volume": "15", "number": "11", "publisher": "Springer", "pagerange": "Art. No. 2011", "id_number": "CaltechAUTHORS:20131105-084834160", "issn": "1388-0764", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131105-084834160", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "EEWS Initiative", "grant_number": "NT080607C0209721" }, { "agency": "National Research Foundation of Korea (NRF) Ministry of Education, Science and Technology (MEST)", "grant_number": "2012M1A2A2026588" }, { "agency": "NSF CBET", "grant_number": "0948485" }, { "agency": "NSF CBET", "grant_number": "0506951" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s11051-013-2011-9", "pub_year": "2013", "author_list": "Fromer, Neil A. and Diallo, Mamadou S." }, { "id": "https://authors.library.caltech.edu/records/p1ksv-0m994", "eprint_id": 41844, "eprint_status": "archive", "datestamp": "2023-08-19 21:50:21", "lastmod": "2023-10-25 14:50:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Piunova-V-A", "name": { "family": "Piunova", "given": "Victoria A." } }, { "id": "Miyake-Garret-M", "name": { "family": "Miyake", "given": "Garret M." } }, { "id": "Daeffler-C-S", "name": { "family": "Daeffler", "given": "Christopher S." } }, { "id": "Weitekamp-R-A", "name": { "family": "Weitekamp", "given": "Raymond A." } }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Highly Ordered Dielectric Mirrors via the Self-Assembly of Dendronized Block Copolymers", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: August 6, 2013. Published: October 4, 2013. \n\nWe gratefully acknowledge Ron Synowicki and Nina Hong at J.A. Woollam Co., Inc. for their measurement and fitting of the refractive indices of these polymers. Reflection measurements were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. This work was supported by a Dow-Resnick Bridge Award. This research was conducted with Government support under and awarded by DoD, Air Force Office of Scientific Research, National Defense Science and Engineering Graduate (NDSEG) Fellowship (32 CFR 168a).", "abstract": "Dendronized block copolymers were synthesized by ruthenium-mediated ring-opening methathesis polymerization of exo-norbornene functionalized dendrimer monomers, and their self-assembly to dielectric mirrors was investigated. The rigid-rod main-chain conformation of these polymers drastically lowers the energetic barrier for reorganization, enabling their rapid self-assembly to long-range, highly ordered nanostructures. The high fidelity of these dielectric mirrors is attributed to the uniform polymer architecture achieved from the construction of discrete dendritic repeat units. These materials exhibit lightreflecting properties due to the multilayer architecture, presenting an attractive bottom-up approach to efficient dielectric mirrors with narrow band gaps. The wavelength of reflectance scales linearly with block-copolymer molecular weight, ranging from the ultraviolet, through the visible, to the near-infrared. This allows for the modulation of photonic properties through synthetic control of the polymer molecular weight. This work represents a significant advancement in closing the gap between the precision obtained from top-down and bottom-up approaches.", "date": "2013-10-04", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "135", "number": "41", "publisher": "American Chemical Society", "pagerange": "15609-15616", "id_number": "CaltechAUTHORS:20131009-162030103", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131009-162030103", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow-Resnick Bridge Award" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship", "grant_number": "32 CFR 168a" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/ja4081502", "pub_year": "2013", "author_list": "Piunova, Victoria A.; Miyake, Garret M.; et al." }, { "id": "https://authors.library.caltech.edu/records/0gejy-m5733", "eprint_id": 42318, "eprint_status": "archive", "datestamp": "2023-08-19 21:34:56", "lastmod": "2023-10-25 15:49:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Current-voltage characteristics of coupled photodiode-electrocatalyst devices", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Institute of Physics Publishing LLC. Received 25 February 2013; accepted 10 September 2013; published online 3 October 2013. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DESC0004993. K.F. is supported by the National Science\nFoundation Graduate Research Fellowship under Grant No.\nDGE-1144469. M.S. acknowledges the support of the Resnick\nSustainability Institute. The authors would like to thank Dr.\nNathan S. Lewis and Dr. Harry A. Atwater for advising during\nthis project and Dr. Shane Ardo for helpful discussions.\n\n

Published - 1.4822179.pdf

", "abstract": "Analytical expressions for the illuminated current-voltage characteristics of coupled photodiode-electrocatalyst fuel forming devices are derived. The approach is based on combining solid-state diode behavior with metal electrochemistry via the diode equation and the Butler-Volmer equation (charge transfer coefficients: \u03b1_A\u2009=\u2009\u03b1_C\u2009=\u2009\u03b1) or the Tafel equation ( |\u03b7|\u2265^(118mV)_(ne)), respectively. The analytical expression for the current-voltage behavior of the coupled photodiode-electrocatalyst device (\u03b1_A\u2009=\u2009\u03b1_C\u2009=\u20090.5) and an isolated photodiode is plotted, compared, and augmented with band diagrams at equilibrium, open circuit, short circuit, and the maximum power point to illustrate the effect of coupling an electrocatalyst to a photodiode. The applicability of the derived equations is then demonstrated by comparing with a recently reported high efficiency, thin film InP/InO_xP_y/Rh photoelectrosynthetic hydrogen evolution device.", "date": "2013-09-30", "date_type": "published", "publication": "Applied Physics Letters", "volume": "103", "number": "14", "publisher": "American Institute of Physics", "pagerange": "Art. No. 143905", "id_number": "CaltechAUTHORS:20131107-150452899", "issn": "0003-6951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131107-150452899", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1063/1.4822179", "primary_object": { "basename": "1.4822179.pdf", "url": "https://authors.library.caltech.edu/records/0gejy-m5733/files/1.4822179.pdf" }, "pub_year": "2013", "author_list": "Shaner, Matthew R.; Fountaine, Katherine T.; et al." }, { "id": "https://authors.library.caltech.edu/records/day4g-efc63", "eprint_id": 42325, "eprint_status": "archive", "datestamp": "2023-08-19 21:35:08", "lastmod": "2023-10-25 15:50:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Drymiotis-F", "name": { "family": "Drymiotis", "given": "Fivos" } }, { "id": "Day-T-W", "name": { "family": "Day", "given": "Tristan W." } }, { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Heinz-N-A", "name": { "family": "Heinz", "given": "Nicholas A." } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Enhanced thermoelectric performance in the very low thermal conductivity Ag_2Se_(0.5)Te_(0.5)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 AIP Publishing LLC. Received 24 July 2013; accepted 22 September 2013; published online 3 October 2013. The authors would like to thank the U.S. Air Force Office of Scientific Research for supporting this work.\n\n

Published - 1.4824353.pdf

", "abstract": "In this letter, we report the high-temperature thermoelectric properties of Ag_2Se_(0.5)Te_(0.5). We find that this particular composition displays very low thermal conductivity and competitive thermoelectric performance. Specifically, in the temperature region 520\u2009K\u2009\u2264\u2009T\u2009\u2264\u2009620\u2009K, we observe non-hysteretic behavior between the heating and cooling curves and zT values ranging from 1.2 to 0.8. Higher zT values are observed at lower temperatures on cooling. Our results suggest that this alloy is conducive to high thermoelectric performance in the intermediate temperature range, and thus deserves further investigation.", "date": "2013-09-30", "date_type": "published", "publication": "Applied Physics Letters", "volume": "103", "number": "14", "publisher": "American Institute of Physics", "pagerange": "Art. No. 143906", "id_number": "CaltechAUTHORS:20131107-154735120", "issn": "0003-6951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131107-154735120", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.4824353", "primary_object": { "basename": "1.4824353.pdf", "url": "https://authors.library.caltech.edu/records/day4g-efc63/files/1.4824353.pdf" }, "pub_year": "2013", "author_list": "Drymiotis, Fivos; Day, Tristan W.; et al." }, { "id": "https://authors.library.caltech.edu/records/vsdpk-r8b62", "eprint_id": 41665, "eprint_status": "archive", "datestamp": "2023-08-22 10:01:12", "lastmod": "2023-10-24 23:55:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Farivar-M", "name": { "family": "Farivar", "given": "Masoud" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Branch Flow Model: Relaxations and Convexification\u2014Part I", "ispublished": "pub", "full_text_status": "public", "keywords": "Convex relaxation; load flow control; optimal power flow; phase control; power system management", "note": "\u00a9 2013 IEEE. Open access. \n\nManuscript received May 11, 2012; revised July 22, 2012, November 18,\n2012, January 04, 2013, and March 01, 2013; accepted March 03, 2013. Date\nof publication April 23, 2013; date of current version July 18, 2013. This work\nwas supported by NSF through NetSE grant CNS 0911041, DoE's ARPA-E\nthrough grant DE-AR0000226, the National Science Council of Taiwan (R. O.\nC.) through grant NSC 101-3113-P-008-001, SCE, the Resnick Institute of Caltech,\nCisco, and the Okawa Foundation. A preliminary and abridged version has\nappeared in [1]. Paper no. TPWRS-00424-2012.\n\nThe authors would like to thank S. Bose, K. M. Chandy, and\nL. Gan of Caltech; C. Clarke, M. Montoya, and R. Sherick of\nthe Southern California Edison (SCE); and B. Lesieutre ofWisconsin\nfor helpful discussions.\n\n

Published - 06507355.pdf

Submitted - 1204.4865v4.pdf

", "abstract": "We propose a branch flow model for the analysis and optimization of mesh as well as radial networks. The model leads to a new approach to solving optimal power flow (OPF) that consists of two relaxation steps. The first step eliminates the voltage and current angles and the second step approximates the resulting problem by a conic program that can be solved efficiently. For radial networks, we prove that both relaxation steps are always exact, provided there are no upper bounds on loads. For mesh networks, the conic relaxation is always exact but the angle relaxation may not be exact, and we provide a simple way to determine if a relaxed solution is globally optimal. We propose convexification of mesh networks using phase shifters so that OPF for the convexified network can always be solved efficiently for an optimal solution. We prove that convexification requires phase shifters only outside a spanning tree of the network and their placement depends only on network topology, not on power flows, generation, loads, or operating constraints. Part I introduces our branch flow model, explains the two relaxation steps, and proves the conditions for exact relaxation. Part II describes convexification of mesh networks, and presents simulation results.", "date": "2013-08", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "28", "number": "3", "publisher": "IEEE", "pagerange": "2554-2564", "id_number": "CaltechAUTHORS:20131003-153831161", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131003-153831161", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF NetSE", "grant_number": "CNS 0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 101-3113-P-008-001" }, { "agency": "Southern California Edison" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Cisco" }, { "agency": "Okawa Foundation" } ] }, "other_numbering_system": { "items": [ { "id": "13686414", "name": "INSPEC Accession Number" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2013.2255317", "primary_object": { "basename": "06507355.pdf", "url": "https://authors.library.caltech.edu/records/vsdpk-r8b62/files/06507355.pdf" }, "related_objects": [ { "basename": "1204.4865v4.pdf", "url": "https://authors.library.caltech.edu/records/vsdpk-r8b62/files/1204.4865v4.pdf" } ], "pub_year": "2013", "author_list": "Farivar, Masoud and Low, Steven H." }, { "id": "https://authors.library.caltech.edu/records/ndxj1-n1k24", "eprint_id": 41349, "eprint_status": "archive", "datestamp": "2023-08-19 20:55:55", "lastmod": "2023-10-24 23:40:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Farivar-M", "name": { "family": "Farivar", "given": "Masoud" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Branch Flow Model: Relaxations and Convexification\u2014Part II", "ispublished": "pub", "full_text_status": "public", "keywords": "Convex relaxation, load flow control, optimal\npower flow, phase control, power system management", "note": "\u00a9 2013 IEEE. An IEEE Open Access article.\n\nManuscript received May 11, 2012; revised July 22, 2012, November 18,\n2012, January 04, 2013, and March 01, 2013; accepted March 03, 2013. Date\nof publication April 23, 2013; date of current version July 18, 2013. The work\nwas supported by NSF through NetSE grant CNS 0911041, Resnick Institute\nof Caltech through grant DE-AR0000226, the DoE's ARPA-E through grant\nDE-AR0000226, the National Science Council of Taiwan (R. O. C.) through\ngrant NSC 101-3113-P-008-001, Southern California Edison, the Resnick Institute\nof Caltech, Cisco, and the Okawa Foundation. A preliminary and abridged\nversion has appeared in [1]. Paper no. TPWRS-00425-2012.\n\nThe authors would like to thank S. Bose, K. M. Chandy, L.\nGan, and B. Hassibi of Caltech, and C. Clarke, M. Montoya, and\nR. Sherick of the Southern California Edison.\n\n

Published - 06507352.pdf

Submitted - 1204.4865v4.pdf

", "abstract": "We propose a branch flow model for the analysis and optimization of mesh as well as radial networks. The model leads to a new approach to solving optimal power flow (OPF) that consists of two relaxation steps. The first step eliminates the voltage and current angles and the second step approximates the resulting problem by a conic program that can be solved efficiently. For radial networks, we prove that both relaxation steps are always exact, provided there are no upper bounds on loads. For mesh networks, the conic relaxation is always exact but the angle relaxation may not be exact, and we provide a simple way to determine if a relaxed solution is globally optimal. We propose convexification of mesh networks using phase shifters so that OPF for the convexified network can always be solved efficiently for an optimal solution. We prove that convexification requires phase shifters only outside a spanning tree of the network and their placement depends only on network topology, not on power flows, generation, loads, or operating constraints. Part I introduces our branch flow model, explains the two relaxation steps, and proves the conditions for exact relaxation. Part II describes convexification of mesh networks, and presents simulation results.", "date": "2013-08", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "28", "number": "3", "publisher": "IEEE", "pagerange": "2565-2572", "id_number": "CaltechAUTHORS:20130916-151203881", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130916-151203881", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF NetSE", "grant_number": "CNS 0911041" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 101-3113-P-008-001" }, { "agency": "Southern California Edison" }, { "agency": "Cisco" }, { "agency": "Okawa Foundation" } ] }, "other_numbering_system": { "items": [ { "id": "13686473", "name": "INSPEC Accession Number" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2013.2255318", "primary_object": { "basename": "06507352.pdf", "url": "https://authors.library.caltech.edu/records/ndxj1-n1k24/files/06507352.pdf" }, "related_objects": [ { "basename": "1204.4865v4.pdf", "url": "https://authors.library.caltech.edu/records/ndxj1-n1k24/files/1204.4865v4.pdf" } ], "pub_year": "2013", "author_list": "Farivar, Masoud and Low, Steven H." }, { "id": "https://authors.library.caltech.edu/records/6hjme-k5b85", "eprint_id": 40971, "eprint_status": "archive", "datestamp": "2023-08-22 09:50:41", "lastmod": "2023-10-24 23:20:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Qiu-Yuting", "name": { "family": "Qiu", "given": "Yuting" } }, { "id": "Xi-Lili", "name": { "family": "Xi", "given": "Lili" } }, { "id": "Shi-Xun", "name": { "family": "Shi", "given": "Xun" } }, { "id": "Qiu-Pengfei", "name": { "family": "Qiu", "given": "Pengfei" } }, { "id": "Zhang-Wenqing", "name": { "family": "Zhang", "given": "Wenqing" } }, { "id": "Chen-Lidong", "name": { "family": "Chen", "given": "Lidong" } }, { "id": "Salvador-J-R", "name": { "family": "Salvador", "given": "James R." } }, { "id": "Cho-Jung-Y", "name": { "family": "Cho", "given": "Jung Y." } }, { "id": "Yang-Jihui", "name": { "family": "Yang", "given": "Jihui" } }, { "id": "Chien-Yuan-Chun", "name": { "family": "Chien", "given": "Yuan-chun" } }, { "id": "Chen-Sinn-Wen", "name": { "family": "Chen", "given": "Sinn-Wen" } }, { "id": "Tang-Yinglu", "name": { "family": "Tang", "given": "Yinglu" } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Charge-Compensated Compound Defects in Ga-containing Thermoelectric Skutterudites", "ispublished": "pub", "full_text_status": "public", "keywords": "thermoelectrics; semiconductors; doping; electrical and thermal transports", "note": "\u00a9 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: September 7, 2012;\nRevised: December 10, 2012;\nPublished online: February 6, 2013.\n\nThis work was supported by the National Basic Research Program of\nChina (973-program) under Project No. 2013CB632501, the National\nNatural Science Foundation of China (NSFC) under the Nos. 11234012, 51222209, 51121064, and 50825205, the Shanghai Science and\nTechnology Commission (Pujiang Program, 11PJ1410200). J.Y. thanks\nthe NSFC (51028201) and NSFC-CAS/SAFEA International Partnership\nProgram for Creative Research Teams, and International S&T Cooperation\nProgram of China (2011DFB60150). J.R.S. and J.Y.C. acknowledge the\nsupport by GM and by the DOE under corporate agreement DE-FC26-\n04NT42278. X.S., J.Y., J.R.S., and J.Y.C. thank J. F. Herbst and M. W.\nVerbrugge for their continued support and encouragement. G.J.S. and\nS.W.C. thank the joint Caltech-Taiwan NSC program under the No. 101-3113-P-008-001.\n\n

Supplemental Material - adfm_201202571_sm_suppl.pdf

", "abstract": "Heavy doping changes an intrinsic semiconductor into a metallic conductor by the introduction of impurity states. However, Ga impurities in thermoelectric skutterudite CoSb_3 with lattice voids provides an example to the contrary. Because of dual-site occupancy of the single Ga impurity charge-compensated compound defects are formed. By combining first-principle calculations and experiments, we show that Ga atoms occupy both the void and Sb sites in CoSb_3 and couple with each other. The donated electrons from the void-filling Ga (GaVF) saturate the dangling bonds from the Sb-substitutional Ga (Ga_(Sb)). The stabilization of Ga impurity as a compound defect extends the region of skutterudite phase stability toward Ga_(0.15)Co_4Sb_(11.95) whereas the solid\u2013solution region in other directions of the ternary phase diagram is much smaller. A proposed ternary phase diagram for Ga-Co-Sb is given. This compensated defect complex leads to a nearly intrinsic semiconductor with heavy Ga doping in CoSb_3 and a much reduced lattice thermal conductivity (\u03ba_L) which can also be attributed to the effective scattering of both the low- and high-frequency lattice phonons by the dual-site occupant Ga impurities. Such a system maintains a low carrier concentration and therefore high thermopower, and the thermoelectric figure of merit quickly increases to 0.7 at a Ga doping content as low as 0.1 per Co_4Sb_(12) and low carrier concentrations on the order of 10^(19) cm^(\u22123).", "date": "2013-07-05", "date_type": "published", "publication": "Advanced Functional Materials", "volume": "23", "number": "25", "publisher": "Wiley", "pagerange": "3194-3203", "id_number": "CaltechAUTHORS:20130828-102406743", "issn": "1616-301X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130828-102406743", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Basic Research Program of China 973 Program", "grant_number": "2013CB632501" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "11234012" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "51222209" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "51121064" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "50825205" }, { "agency": "Shanghai Science and Technology Commission Pujiang Program", "grant_number": "11PJ1410200" }, { "agency": "National Natural Science Foundation of China (NSFC)", "grant_number": "51028201" }, { "agency": "NSFC-CAS/SAFEA International Partnership Program for Creative Research Teams" }, { "agency": "International S&T Cooperation Program of China", "grant_number": "2011DFB60150" }, { "agency": "GM" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FC26-04NT42278" }, { "agency": "Caltech-Taiwan NSC Program", "grant_number": "101-3113-P-008-001" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/adfm.201202571", "primary_object": { "basename": "adfm_201202571_sm_suppl.pdf", "url": "https://authors.library.caltech.edu/records/6hjme-k5b85/files/adfm_201202571_sm_suppl.pdf" }, "pub_year": "2013", "author_list": "Qiu, Yuting; Xi, Lili; et al." }, { "id": "https://authors.library.caltech.edu/records/t8ray-0c014", "eprint_id": 40329, "eprint_status": "archive", "datestamp": "2023-08-19 20:32:11", "lastmod": "2023-10-24 17:20:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-D-R", "name": { "family": "Brown", "given": "David R." } }, { "id": "Day-T-W", "name": { "family": "Day", "given": "Tristan" } }, { "id": "Caillat-T", "name": { "family": "Caillat", "given": "Thierry" } }, { "id": "Snyder-G-J", "name": { "family": "Snyder", "given": "G. Jeffrey" }, "orcid": "0000-0003-1414-8682" } ] }, "title": "Chemical Stability of (Ag,Cu)_2Se: a Historical Overview", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 TMS.\nReceived September 13, 2012; accepted January 19, 2013;\npublished online March 12, 2013.\n\nD.R.B. would like to acknowledge the support of\nthe Resnick Institute. T.D. and G.J.S. would like to\nacknowledge the support of the Air Force Office of\nScience Research. Part of this work was carried out at\nthe Jet Propulsion Laboratory, California Institute\nof Technology, under a contract with the National\nAeronautics and Space Administration.", "abstract": "Recent work on Cu_(2\u2212x) Se has caused strong interest in this material due to its high reported peak zT (1.5) and the reduction of thermal conductivity through the mechanism of liquid-like suppression of heat capacity. In the 1960s, 3M patented Cu_(1.97)Ag_(0.03)Se as \"TPM-217.\" Over the following decade it was tested and developed by the 3M Corporation, at the National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory, Teledyne Energy Systems, and the General Atomics Corporation for use as a next-generation thermoelectric material. During these tests, extreme problems with material loss through Se vaporization and chemical reactions between the material and the device contacts were found. These problems were especially severe while operating under conditions of high iL/A. As a result, the material system was abandoned. The results of these reports are discussed. A simple test of degradation of Cu_2Se under conditions of applied current and thermal gradient was performed and showed results compatible with the work done by General Atomics.", "date": "2013-07", "date_type": "published", "publication": "Journal of Electronic Materials", "volume": "42", "number": "7", "publisher": "Springer", "pagerange": "2014-2019", "id_number": "CaltechAUTHORS:20130816-080656183", "issn": "0361-5235", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130816-080656183", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Institute" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1007/s11664-013-2506-2", "pub_year": "2013", "author_list": "Brown, David R.; Day, Tristan; et al." }, { "id": "https://authors.library.caltech.edu/records/6bhnt-fy360", "eprint_id": 41651, "eprint_status": "archive", "datestamp": "2023-08-22 09:16:19", "lastmod": "2023-10-24 23:54:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gan-Lingwen", "name": { "family": "Gan", "given": "Lingwen" } }, { "id": "Topcu-U", "name": { "family": "Topcu", "given": "Ufuk" } }, { "id": "Low-S-H", "name": { "family": "Low", "given": "Steven H." }, "orcid": "0000-0001-6476-3048" } ] }, "title": "Optimal Decentralized Protocol for Electric Vehicle Charging", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Controllable electric load; distributed optimal control; electric vehicle charging; valley-filling", "note": "\u00a9 2012 IEEE.\n\nManuscript received November 12, 2011; revised February 29, 2012 and May 28, 2012; accepted July 13, 2012. Date of publication September 27, 2012; date of current version April 18, 2013. \n\nThis work was supported by Bell Labs of Alcatel-Lucent, NSF NetSE grant CNS 0911041, ARPA-E grant DE-AR0000226, Southern California Edison, National Science Council of Taiwan, R.O.C, grant NSC 101-3113-P-008-001, Resnick Institute, Okawa Foundation, Boeing Corporation, Cisco, and AFOSR award number FA9550-12-1-0302. Paper no. TPWRS-01087-2011. \n\nThe authors would like to thank K. Mani Chandy and S. Adlakha for inspiring discussions.", "abstract": "We propose a decentralized algorithm to optimally schedule electric vehicle (EV) charging. The algorithm exploits the elasticity of electric vehicle loads to fill the valleys in electric load profiles. We first formulate the EV charging scheduling problem as an optimal control problem, whose objective is to impose a generalized notion of valley-filling, and study properties of optimal charging profiles. We then give a decentralized algorithm to iteratively solve the optimal control problem. In each iteration, EVs update their charging profiles according to the control signal broadcast by the utility company, and the utility company alters the control signal to guide their updates. The algorithm converges to optimal charging profiles (that are as \"flat\" as they can possibly be) irrespective of the specifications (e.g., maximum charging rate and deadline) of EVs, even if EVs do not necessarily update their charging profiles in every iteration, and use potentially outdated control signal when they update. Moreover, the algorithm only requires each EV solving its local problem, hence its implementation requires low computation capability. We also extend the algorithm to track a given load profile and to real-time implementation.", "date": "2013-05", "date_type": "published", "publication": "IEEE Transactions on Power Systems", "volume": "28", "number": "2", "publisher": "IEEE", "pagerange": "940-951", "id_number": "CaltechAUTHORS:20131003-094643635", "issn": "0885-8950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131003-094643635", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bell Labs of Alcatel-Lucent" }, { "agency": "NSF", "grant_number": "CNS 0911041" }, { "agency": "ARPA-E", "grant_number": "DE-AR0000226" }, { "agency": "Southern California Edison" }, { "agency": "National Science Council (Taipei)", "grant_number": "NSC 101-3113-P-008-001" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Okawa Foundation" }, { "agency": "Boeing Corporation" }, { "agency": "Cisco" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0302" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1109/TPWRS.2012.2210288", "pub_year": "2013", "author_list": "Gan, Lingwen; Topcu, Ufuk; et al." }, { "id": "https://authors.library.caltech.edu/records/gtgyz-mwp78", "eprint_id": 37144, "eprint_status": "archive", "datestamp": "2023-08-22 08:32:15", "lastmod": "2023-10-23 17:00:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Smith-M-A", "name": { "family": "Smith", "given": "Matthew A." } }, { "id": "Romero-P-A", "name": { "family": "Romero", "given": "Philip A." }, "orcid": "0000-0002-2586-7263" }, { "id": "Wu-Timothy", "name": { "family": "Wu", "given": "Timothy" } }, { "id": "Brustad-E-M", "name": { "family": "Brustad", "given": "Eric M." }, "orcid": "0000-0002-7031-5433" }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "Chimeragenesis of distantly-related proteins by noncontiguous recombination", "ispublished": "pub", "full_text_status": "restricted", "keywords": "chimeragenesis; protein recombination; eukaryotic-prokaryotic chimera; GH1; structural conservation; graph partitioning", "note": "\u00a9 2012 The Protein Society.\n\nReceived 3 October 2012; Revised 21 November 2012; Accepted 26 November 2012.\nArticle first published online: 29 Dec. 2012.\nGrant sponsors: Institute for Collaborative Biotechnologies and US Army Research Office (Grant number: W911NF-09-D-0001); The National Central University, Taiwan (Cooperative Agreement for Energy Research Collaboration); Grant sponsor: Gordon and Betty Moore Foundation, the Beckman Institute and Caltech (the Sanofi-Aventis Bioengineering Research Program); Grant sponsor: US\nDOE and NIH (Beamline operations at SSRL); Grant sponsor: Resnick Sustainability Institute (fellowship; M.A.S.).\n\nThe authors thank A. Wang of the Academia Sinica, Taiwan, for providing the TrBgl2 gene and T. Gloster and G. Davies of the University of York, UK, for providing the TmBglA gene. The authors also acknowledge the Molecular Observatory at Caltech for their support with X-ray crystallography. The content of the information in this document does not necessarily reflect the position or the policy of the sponsoring agencies, and no official endorsement should be inferred.", "abstract": "We introduce a method for identifying elements of a protein structure that can be shuffled to make chimeric proteins from two or more homologous parents. Formulating recombination as a graph-partitioning problem allows us to identify noncontiguous segments of the sequence that should be inherited together in the progeny proteins. We demonstrate this noncontiguous recombination approach by constructing a chimera of \u03b2-glucosidases from two different kingdoms of life. Although the protein's alpha\u2013beta barrel fold has no obvious subdomains for recombination, noncontiguous SCHEMA recombination generated a functional chimera that takes approximately half its structure from each parent. The X-ray crystal structure shows that the structural blocks that make up the chimera maintain the backbone conformations found in their respective parental structures. Although the chimera has lower \u03b2-glucosidase activity than the parent enzymes, the activity was easily recovered by directed evolution. This simple method, which does not rely on detailed atomic models, can be used to design chimeras that take structural, and functional, elements from distantly-related proteins.", "date": "2013-02", "date_type": "published", "publication": "Protein Science", "volume": "22", "number": "2", "publisher": "Wiley", "pagerange": "231-238", "id_number": "CaltechAUTHORS:20130226-103727663", "issn": "0961-8368", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130226-103727663", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-09-D-0001" }, { "agency": "National Central University (Taiwan)" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Department of Energy (DOE)" }, { "agency": "NIH" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Sanofi-Aventis Bioengineering Research Program" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/pro.2202", "pmcid": "PMC3588919", "pub_year": "2013", "author_list": "Smith, Matthew A.; Romero, Philip A.; et al." }, { "id": "https://authors.library.caltech.edu/records/4chye-shs05", "eprint_id": 38108, "eprint_status": "archive", "datestamp": "2023-08-22 08:36:21", "lastmod": "2025-04-23 01:12:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Grandidier-J", "name": { "family": "Grandidier", "given": "Jonathan" }, "orcid": "0000-0002-3384-6083" }, { "id": "Weitekamp-R-A", "name": { "family": "Weitekamp", "given": "Raymond A." } }, { "id": "Deceglie-M-G", "name": { "family": "Deceglie", "given": "Michael G." } }, { "id": "Callahan-D-M", "name": { "family": "Callahan", "given": "Dennis M." } }, { "id": "Battaglia-C", "name": { "family": "Battaglia", "given": "Corsin" }, "orcid": "0000-0002-5003-1134" }, { "id": "Bukowsky-C-R", "name": { "family": "Bukowsky", "given": "Colton R." }, "orcid": "0000-0003-3577-8050" }, { "id": "Ballif-C", "name": { "family": "Ballif", "given": "Christophe" }, "orcid": "0000-0001-8989-0545" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Solar cell efficiency enhancement via light trapping in printable resonant dielectric nanosphere arrays", "ispublished": "pub", "full_text_status": "public", "keywords": "amorphous silicon; nanospheres; photonic crystal; photovoltaics; resonant dielectric structures; solar cells", "note": "\u00a9 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived 5 October 2012; revised 24 October 2012; accepted 24 October 2012; Published online 22 November 2012. \n\nThe authors wish to thank A. J. Leenheer. A. Mihi. P. V. Braun, M. Charri\u00e8re. and K S\u00f6derstr\u00f6m for useful technical input. The work at Caltech was supported by the \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001293. The work at EPFL was supported by the Swiss Federal Energy Office. RAW thanks the Resnick Sustainability Institute for a graduate fellowship.\n\n

Supplemental Material - pssa_201228690_sm_movie.mov

Supplemental Material - pssa_201228690_sm_suppdata.pdf

", "abstract": "Resonant dielectric structures are a promising platform for addressing the key challenge of light trapping in thin-film solar cells. We experimentally and theoretically demonstrate efficiency enhancements in solar cells from dielectric nanosphere arrays. Two distinct amorphous silicon photovoltaic architectures were improved using this versatile light-trapping platform. In one structure, the colloidal monolayer couples light into the absorber in the near-field acting as a photonic crystal light-trapping element. In the other, it acts in the far-field as a graded index antireflection coating to further improve a cell which already included a state-of-the-art random light-trapping texture to achieve a conversion efficiency over 11%. For the near-field flat cell architecture, we directly fabricated the colloidal monolayer on the device through Langmuir\u2013Blodgett deposition in a scalable process that does not degrade the active material. In addition, we present a novel transfer printing method, which utilizes chemical crosslinking of an optically thin adhesion layer to tether sphere arrays to the device surface. The minimally invasive processing conditions of this transfer method enable the application to a wide range of solar cells and other optoelectronic devices.\n\nFalse-color SEM image of an amorphous silicon solar cell with resonant spheres on top.", "date": "2013-02", "date_type": "published", "publication": "Physica Status Solidi A", "volume": "210", "number": "2", "publisher": "Wiley", "pagerange": "255-260", "id_number": "CaltechAUTHORS:20130424-160158368", "issn": "0031-8965", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130424-160158368", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Swiss Federal Energy Office" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/pssa.201228690", "primary_object": { "basename": "pssa_201228690_sm_movie.mov", "url": "https://authors.library.caltech.edu/records/4chye-shs05/files/pssa_201228690_sm_movie.mov" }, "related_objects": [ { "basename": "pssa_201228690_sm_suppdata.pdf", "url": "https://authors.library.caltech.edu/records/4chye-shs05/files/pssa_201228690_sm_suppdata.pdf" } ], "pub_year": "2013", "author_list": "Grandidier, Jonathan; Weitekamp, Raymond A.; et al." }, { "id": "https://authors.library.caltech.edu/records/jq6bg-hcq89", "eprint_id": 41557, "eprint_status": "archive", "datestamp": "2023-08-22 08:12:08", "lastmod": "2025-04-23 19:51:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kosten-E-D", "name": { "family": "Kosten", "given": "Emily D." } }, { "id": "Atwater-J-H", "name": { "family": "Atwater", "given": "Jackson H." } }, { "id": "Parsons-J", "name": { "family": "Parsons", "given": "James" } }, { "id": "Polman-A", "name": { "family": "Polman", "given": "A." }, "orcid": "0000-0002-0685-3886" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "H. A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Highly Efficient GaAs solar cells by limiting light emission angle", "ispublished": "pub", "full_text_status": "public", "keywords": "detailed balance; GaAs solar cell; light trapping; photovoltaics; two photon lithography", "note": "\u00a9 2013 Changchun Institute of Optics, Fine Mechanics and Physics. This work is licensed under the Creative Commons Attribution-NonCommercial-No Derivative Works 3.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/3.0/. \n\nReceived 25 April 2012; revised 17 September 2012; accepted 24 September 2012. \n\nThanks to D Callahan,M Sheldon and J van de Groep for insightful discussions\nand advice on the manuscript. The authors also found advice from O Miller on\nhandling non-radiative recombination, R Briggs on mode structure\ncalculations, J Zipkin on numerical methods and C Eisler on internal\nfluorescence yield derivations extremely helpful. The authors are grateful for\ntechnical assistance from GVollenbroek. The Caltech researchers are supported\nby the 'Light-Material Interactions in Energy Conversion' Energy Frontier\nResearch Center funded by the US Department of Energy, Office of Science,\nOffice of Basic Energy Sciences under grant DE-SC0001293 (EK and HA). EK\nalso acknowledges the support of the Resnick Sustainability Institute.\nResearchers of the Center for Nanophotonics at AMOLF are supported by\nthe research program of FOM which is financially supported by NWO and\nby the European Research Council.\n\n

Supplemental Material - lsa20131a.pdf

", "abstract": "In a conventional flat plate solar cell under direct sunlight, light is received from the solar disk, but is re-emitted isotropically. This\nisotropic emission corresponds to a significant entropy increase in the solar cell, with a corresponding drop in efficiency. Here, using a\ndetailed balance model, we show that limiting the emission angle of a high-quality GaAs solar cell is a feasible route to achieving power\nconversion efficiencies above 38% with a single junction. The highest efficiencies are predicted for a thin, light trapping cell with an\nideal back reflector, though the scheme is robust to a non-ideal back reflector. Comparison with a conventional planar cell geometry\nillustrates that limiting emission angle in a light trapping geometry not only allows for much thinner cells, but also for significantly\nhigher overall efficiencies with an excellent rear reflector. Finally, we present ray-tracing and detailed balance analysis of two angular\ncoupler designs, show that significant efficiency improvements are possible with these couplers, and demonstrate initial fabrication of\none coupler design.", "date": "2013-01-04", "date_type": "published", "publication": "Light: Science & Applications", "volume": "2", "number": "1", "publisher": "Nature Publishing Group", "pagerange": "Art. No. e45", "id_number": "CaltechAUTHORS:20130930-121333431", "issn": "2047-7538", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130930-121333431", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "European Research Council (ERC)" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/lsa.2013.1", "primary_object": { "basename": "lsa20131a.pdf", "url": "https://authors.library.caltech.edu/records/jq6bg-hcq89/files/lsa20131a.pdf" }, "pub_year": "2013", "author_list": "Kosten, Emily D.; Atwater, Jackson H.; et al." }, { "id": "https://authors.library.caltech.edu/records/k02hw-phx55", "eprint_id": 36350, "eprint_status": "archive", "datestamp": "2023-08-22 07:50:15", "lastmod": "2023-10-20 23:04:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Smith-M-A", "name": { "family": "Smith", "given": "Matthew A." } }, { "id": "Rentmeister-A", "name": { "family": "Rentmeister", "given": "Andrea" }, "orcid": "0000-0002-3107-4147" }, { "id": "Snow-C-D", "name": { "family": "Snow", "given": "Christopher D." }, "orcid": "0000-0002-7690-3519" }, { "id": "Wu-Timothy", "name": { "family": "Wu", "given": "Timothy" } }, { "id": "Farrow-M-F", "name": { "family": "Farrow", "given": "Mary F." } }, { "id": "Mingardon-F", "name": { "family": "Mingardon", "given": "Florence" } }, { "id": "Arnold-F-H", "name": { "family": "Arnold", "given": "Frances H." }, "orcid": "0000-0002-4027-364X" } ] }, "title": "A diverse set of family 48 bacterial glycoside hydrolase cellulases created by structure-guided recombination", "ispublished": "pub", "full_text_status": "public", "keywords": "cellulases; cellulosomal; Cel48; SCHEMA recombination", "note": "\u00a9 2012 The Authors Journal compilation. \u00a9 2012 FEBS.\n\nReceived 16 June 2012; revised 10 October 2012; accepted 12 October 2012.\nArticle first published online: 9 Nov. 2012.\nThis work was supported by the Department of the Interior through grant D10AP00065 from the Defense Advanced Research Projects Agency to F. H. Arnold. M. A. Smith is supported by a Resnick Sustainability Institute fellowship, A. Rentmeister by a DFG postdoctoral fellowship, and T. Wu by a CIT summer\nundergraduate research fellowship (SURF).\n\n

Supplemental Material - febs12032-sup-0001-DocS1-FigureS1-S9-TableS1-S7-Equation1-2.zip

", "abstract": "Sequence diversity within a family of functional enzymes provides a platform for elucidating structure\u2013function relationships and for protein engineering to improve properties important for applications. Access to nature's vast sequence diversity is often limited by the fact that only a few enzymes have been characterized in a given family. Here, we recombined the catalytic domains of three glycoside hydrolase family 48 bacterial cellulases (Cel48; EC 3.2.1.176) \u2013 Clostridium cellulolyticum CelF, Clostridium stercorarium CelY, and Clostridium thermocellum CelS \u2013 to create a diverse library of Cel48 enzymes with an average of 106 mutations from the closest native enzyme. Within this set, we found large variations in properties such as the functional temperature range, stability, and specific activity on crystalline cellulose. We showed that functional status and stability were predictable from simple linear models of the sequence\u2013property data: recombined protein fragments contributed additively to these properties in a given chimera. Using this, we correctly predicted sequences that were as stable as any of the native Cel48 enzymes described to date. The characterization of 60 active Cel48 chimeras expands the number of characterized Cel48 enzymes from 13 to 73. Our work illustrates the role that structure-guided recombination can play in helping to identify sequence\u2013function relationships within a family of enzymes by supplementing natural diversity with synthetic diversity.", "date": "2012-12", "date_type": "published", "publication": "FEBS Journal", "volume": "279", "number": "24", "publisher": "Federation of European Biochemical Societies", "pagerange": "4453-4465", "id_number": "CaltechAUTHORS:20130114-102154716", "issn": "1742-464X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130114-102154716", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "D10AP00065" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1111/febs.12032", "primary_object": { "basename": "febs12032-sup-0001-DocS1-FigureS1-S9-TableS1-S7-Equation1-2.zip", "url": "https://authors.library.caltech.edu/records/k02hw-phx55/files/febs12032-sup-0001-DocS1-FigureS1-S9-TableS1-S7-Equation1-2.zip" }, "pub_year": "2012", "author_list": "Smith, Matthew A.; Rentmeister, Andrea; et al." }, { "id": "https://authors.library.caltech.edu/records/6cp14-np423", "eprint_id": 36035, "eprint_status": "archive", "datestamp": "2023-08-22 07:43:14", "lastmod": "2023-10-20 22:09:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miyake-Garret-M", "name": { "family": "Miyake", "given": "Garret M." } }, { "id": "Piunova-V-A", "name": { "family": "Piunova", "given": "Victoria A." } }, { "id": "Weitekamp-R-A", "name": { "family": "Weitekamp", "given": "Raymond A." } }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Precisely Tunable Photonic Crystals From Rapidly Self-Assembling Brush Block Copolymer Blends", "ispublished": "pub", "full_text_status": "restricted", "keywords": "block copolymers; macromonomers; photonic crystals; ring-opening polymerization; self-assembly", "note": "\u00a9 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived: July 18, 2012. Published online: September 13, 2012. \n\nThis work was supported by a Dow Resnick Bridge Award. R.A.W. thanks the Resnick Sustainability Institute for a graduate fellowship.", "abstract": "Colorful: Enabled by their reduced capacity for chain entanglement, high-molecular-weight brush block copolymers can rapidly self-assemble to photonic crystals. The blending of two polymers of different molecular weight can predictably modulate the sizes of the polymer domains, giving rise to a facile means of precision tuning of these photonic-band-gap materials.", "date": "2012-11-05", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "51", "number": "45", "publisher": "Wiley", "pagerange": "11246-11248", "id_number": "CaltechAUTHORS:20121219-074712292", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121219-074712292", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow Resnick Bridge Award" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201205743", "pub_year": "2012", "author_list": "Miyake, Garret M.; Piunova, Victoria A.; et al." }, { "id": "https://authors.library.caltech.edu/records/65898-qt590", "eprint_id": 35685, "eprint_status": "archive", "datestamp": "2023-08-19 13:14:29", "lastmod": "2023-10-20 20:29:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Abrecht-D-G", "name": { "family": "Abrecht", "given": "David G." } }, { "id": "Fultz-B", "name": { "family": "Fultz", "given": "Brent" }, "orcid": "0000-0002-6364-8782" } ] }, "title": "Evaluation of the Thermodynamic Properties of H_2 Binding in Solid State Dihydrogen Complexes [M(\u03b7^2\u2011H_2)(CO)dppe_2][BArF^(24)] (M = Mn, Tc, Re): An Experimental and First Principles Study", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Chemical Society. \n\nReceived: August 16, 2012. Revised: October 2, 2012. Publication Date (Web): October 15, 2012. \n\nThe authors thank David Vandervelde of Caltech for his assistance with NMR experiments and Joseph Reiter and Jason Zan at the Jet Propulsion Laboratory in Pasadena, CA, for their assistance in planning thermodynamic measurements. Sieverts instrument work was performed at the Jet Propulsion Laboratory, which is operated by the California Institute of Technology under contract with NASA. The Caltech NMR facility is partially supported by the National Institutes of Health through Grant NIH RR027690. We are grateful to the Resnick Sustainability Institute for financial support. \n\nThe authors declare no competing financial interest.\n\n

Accepted Version - nihms415290.pdf

", "abstract": "The solid state complex [Mn(CO)dppe_2][BArF^(24)] was synthesized, and the thermodynamic behavior and properties of the hydrogen absorption reaction to form the dihydrogen complex [Mn(\u03b7^2-H_2)dppe_2][BArF^(24)] were measured over the temperature range 313\u2013373 K and pressure range 0\u2013600 Torr using the Sieverts method. The absorption behavior was accurately described by Langmuir isotherms, and enthalpy and entropy values of \u0394H\u00b0 = \u221252.2 kJ/mol and \u0394S\u00b0 = \u221299.6 J/(mol K) for the absorption reaction were obtained from the Langmuir equilibrium constant. The observed binding strength was similar to metal hydrides and other organometallic complexes, despite rapid kinetics suggesting a site-binding mechanism similar to physisorption materials. Electronic structure calculations using the LANL2DZ-ECP basis set were performed for hydrogen absorption over the organometallic fragments [M(CO)dppe_2]^+ (M = Mn, Tc, Re). Langmuir isotherms derived from calculation for absorption onto the manganese fragment successfully simulated both the pressure\u2013composition behavior and thermodynamic properties obtained from experiment. Results from calculations for the substitution of the metal center reproduced qualitative binding strength trends of 5d > 3d > 4d previously reported for the group 6 metals.", "date": "2012-10-25", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "116", "number": "42", "publisher": "American Chemical Society", "pagerange": "22245-22252", "id_number": "CaltechAUTHORS:20121127-143917563", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121127-143917563", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "NIH", "grant_number": "RR027690" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/jp308176f", "pmcid": "PMC3521573", "primary_object": { "basename": "nihms415290.pdf", "url": "https://authors.library.caltech.edu/records/65898-qt590/files/nihms415290.pdf" }, "pub_year": "2012", "author_list": "Abrecht, David G. and Fultz, Brent" }, { "id": "https://authors.library.caltech.edu/records/bmdqd-5z881", "eprint_id": 35658, "eprint_status": "archive", "datestamp": "2023-08-19 12:38:03", "lastmod": "2025-04-23 03:08:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sveinbj\u00f6rnsson-B-R", "name": { "family": "Sveinbj\u00f6rnsson", "given": "Benjamin R." } }, { "id": "Weitekamp-R-A", "name": { "family": "Weitekamp", "given": "Raymond A." } }, { "id": "Miyake-Garret-M", "name": { "family": "Miyake", "given": "Garret M." } }, { "id": "Xia-Yan", "name": { "family": "Xia", "given": "Yan" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Rapid self-assembly of brush block copolymers to photonic crystals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 National Academy of Sciences. \n\nContributed by Robert H. Grubbs, July 30, 2012 (sent for review July 3, 2012). Published online before print August 21, 2012. \n\nThis work was supported by the NSF (CHE-1048404). R.A.W. was supported in part by the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (DE-SC0001293). R.A.W. thanks the Resnick Institute for a graduate fellowship. Reflection measurements were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. We thank Zhen-Gang Wang for helpful discussions and Bryce Sadtler for assistance with the reflection\nmeasurements. \n\nB.R.S. and R.A.W. contributed equally to this work. \n\nAuthor contributions: R.A.W., Y.X., and R.H.G. designed research; B.R.S., R.A.W., G.M.M., and Y.X. performed research; B.R.S. contributed new reagents/analytic tools; B.R.S., R.A.W., G.M.M., Y.X., and H.A.A. analyzed data; and B.R.S., R.A.W., G.M.M., Y.X., H.A.A., and R.H.G. wrote the paper. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/\ndoi:10.1073/pnas.1213055109/-/DCSupplemental. \n\nThe authors declare no conflict of interest.\n\n

Published - PNAS-2012-Sveinbjornsson-14332-6.pdf

Supplemental Material - Appendix.pdf

", "abstract": "The reduced chain entanglement of brush polymers over their linear analogs drastically lowers the energetic barriers to reorganization. In this report, we demonstrate the rapid self-assembly of brush block copolymers to nanostructures with photonic bandgaps spanning the entire visible spectrum, from ultraviolet (UV) to near infrared (NIR). Linear relationships were observed between the peak wavelengths of reflection and polymer molecular weights. This work enables \"bottom-up\" fabrication of photonic crystals with application-tailored bandgaps, through synthetic control of the polymer molecular weight and the method of self-assembly. These polymers could be developed into NIR-reflective paints, to combat the \"urban heat island effect\" due to NIR photon thermalization.", "date": "2012-09-04", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "109", "number": "36", "publisher": "National Academy of Sciences", "pagerange": "14332-14336", "id_number": "CaltechAUTHORS:20121127-085052551", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121127-085052551", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1048404" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.1213055109", "pmcid": "PMC3437898", "primary_object": { "basename": "Appendix.pdf", "url": "https://authors.library.caltech.edu/records/bmdqd-5z881/files/Appendix.pdf" }, "related_objects": [ { "basename": "PNAS-2012-Sveinbjornsson-14332-6.pdf", "url": "https://authors.library.caltech.edu/records/bmdqd-5z881/files/PNAS-2012-Sveinbjornsson-14332-6.pdf" } ], "pub_year": "2012", "author_list": "Sveinbj\u00f6rnsson, Benjamin R.; Weitekamp, Raymond A.; et al." }, { "id": "https://authors.library.caltech.edu/records/1my8g-acw75", "eprint_id": 33924, "eprint_status": "archive", "datestamp": "2023-08-19 12:24:40", "lastmod": "2023-10-18 21:37:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miyake-Garret-M", "name": { "family": "Miyake", "given": "Garret M." } }, { "id": "Weitekamp-R-A", "name": { "family": "Weitekamp", "given": "Raymond A." } }, { "id": "Piunova-V-A", "name": { "family": "Piunova", "given": "Victoria A." } }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Synthesis of Isocyanate-Based Brush Block Copolymers and Their Rapid Self-Assembly to Infrared-Reflecting Photonic Crystals", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2012 American Chemical Society. \n\nReceived: July 2, 2012. Published: August 14, 2012. \n\nThis work was supported by the NSF (CHE-1048404). R.A.W. thanks the Resnick Institute for a graduate fellowship.", "abstract": "The synthesis of rigid-rod, helical isocyanate-based macromonomers was achieved through the polymerization of hexyl isocyanate and 4-phenylbutyl isocyanate, initiated by an exo-norbornene functionalized half-titanocene complex. Sequential ruthenium-mediated ring-opening metathesis polymerization of these macromonomers readily afforded well-defined brush block copolymers, with precisely tunable molecular weights ranging from high (1512 kDa) to ultrahigh (7119 kDa), while maintaining narrow molecular weight distributions (PDI = 1.08\u20131.39). The self-assembly of these brush block copolymers to solid thin-films and their photonic properties were investigated. Due to the rigid architecture of these novel polymeric materials, they rapidly self-assemble through simple controlled evaporation to photonic crystal materials that reflect light from the ultra-violet, through the visible, to the near-infrared. The wavelength of reflectance is linearly related to the brush block copolymer molecular weight, allowing for predictable tuning of the band gap through synthetic control of the polymer molecular weight. A combination of scanning electron microscopy and optical modeling was employed to explain the origin of reflectivity.", "date": "2012-08-29", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "134", "number": "34", "publisher": "American Chemical Society", "pagerange": "14249-14254", "id_number": "CaltechAUTHORS:20120907-091822265", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120907-091822265", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1048404" }, { "agency": "Resnick Institute Graduate Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/ja306430k", "pub_year": "2012", "author_list": "Miyake, Garret M.; Weitekamp, Raymond A.; et al." }, { "id": "https://authors.library.caltech.edu/records/h52ra-tt269", "eprint_id": 32012, "eprint_status": "archive", "datestamp": "2023-08-19 11:21:11", "lastmod": "2023-10-17 22:21:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cho-Clara-J", "name": { "family": "Cho", "given": "Clara J." } }, { "id": "O'Leary-L-E", "name": { "family": "O'Leary", "given": "Leslie" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "In Situ Nanomechanical Measurements of Interfacial Strength in Membrane-Embedded Chemically Functionalized Si Microwires for Flexible Solar Cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Chemical Society.\n\nReceived: April 14, 2012;\nRevised: May 9, 2012;\nPublished: May 21, 2012.\n\nC.J.C. gratefully acknowledges the financial support of the\nResnick Institute at Caltech through her graduate fellowship\nand E. Warren for help with wafer patterning. L.O'L. thanks the\nfinancial support of the Link Foundation Energy fellowship.\nN.S.L.'s portion of this work was supported by the National\nScience Foundation (NSF-CHE-0911682) and (NSF-CHE-0802907). J.R.G. is grateful to the Caltech's CI-2 Innovation\nGrant for supporting this work.\n\n

Supplemental Material - nl3014007_si_001.pdf

Supplemental Material - nl3014007_si_002.mp4

Supplemental Material - nl3014007_si_003.mp4

", "abstract": "Arrays of vertically aligned Si microwires embedded in polydimethylsiloxane (PDMS) have emerged as a promising candidate for use in solar energy conversion devices. Such structures are lightweight and concurrently demonstrate competitive efficiency and mechanical flexibility. To ensure reliable functioning under bending and flexing, strong interfacial adhesion between the nanowire and the matrix is needed. In situ uniaxial tensile tests of individual, chemically functionalized, Si microwires embedded in a compliant PDMS matrix reveal that chemical functionality on Si microwire surfaces is directly correlated with interfacial adhesion strength. Chemical functionalization can therefore serve as an effective methodology for accessing a wide range of interfacial adhesion between the rigid constituents and the soft polymer matrix; the adhesion can be quantified by measuring the mechanical strength of such systems.", "date": "2012-06-13", "date_type": "published", "publication": "Nano Letters", "volume": "12", "number": "6", "publisher": "American Chemical Society", "pagerange": "3296-3301", "id_number": "CaltechAUTHORS:20120621-133116661", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120621-133116661", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Institute" }, { "agency": "Link Foundation Energy fellowship" }, { "agency": "NSF", "grant_number": "CHE-0911682" }, { "agency": "NSF", "grant_number": "CHE-0802907" }, { "agency": "Caltech's CI-2 Innovation Grant" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" } ] }, "doi": "10.1021/nl3014007", "primary_object": { "basename": "nl3014007_si_003.mp4", "url": "https://authors.library.caltech.edu/records/h52ra-tt269/files/nl3014007_si_003.mp4" }, "related_objects": [ { "basename": "nl3014007_si_001.pdf", "url": "https://authors.library.caltech.edu/records/h52ra-tt269/files/nl3014007_si_001.pdf" }, { "basename": "nl3014007_si_002.mp4", "url": "https://authors.library.caltech.edu/records/h52ra-tt269/files/nl3014007_si_002.mp4" } ], "pub_year": "2012", "author_list": "Cho, Clara J.; O'Leary, Leslie; et al." } ]