[ { "id": "authors:2jgrw-y1x44", "collection": "authors", "collection_id": "2jgrw-y1x44", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221003-756400000.29", "type": "article", "title": "Chemical transformation of a long-chain alkyl organosulfate via heterogeneous OH oxidation: a case study of sodium dodecyl sulfate", "author": [ { "family_name": "Ng", "given_name": "Sze In Madeleine", "orcid": "0000-0003-0919-2603", "clpid": "Ng-Sze-In-Madeleine" }, { "family_name": "Ng", "given_name": "Kwan Hung", "clpid": "Ng-Kwan-Hung" }, { "family_name": "Yeung", "given_name": "Pui Wo Felix", "orcid": "0000-0002-2897-5577", "clpid": "Yeung-Pui-Wo-Felix" }, { "family_name": "Xu", "given_name": "Rongshuang", "clpid": "Xu-Rongshuang" }, { "family_name": "So", "given_name": "Pui-Kin", "clpid": "So-Pui-Kin" }, { "family_name": "Huang", "given_name": "Yuanlong", "orcid": "0000-0002-6726-8904", "clpid": "Huang-Yuanlong" }, { "family_name": "Yu", "given_name": "Jian Zhen", "orcid": "0000-0002-6165-6500", "clpid": "Yu-Jian-Zhen" }, { "family_name": "Choi", "given_name": "Chun Kit K.", "orcid": "0000-0003-1994-1719", "clpid": "Choi-Chun-Kit-K" }, { "family_name": "Tse", "given_name": "Ying-Lung Steve", "orcid": "0000-0003-1187-2296", "clpid": "Tse-Ying-Lung-Steve" }, { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" } ], "abstract": "Organosulfates (OSs) are regarded as stable tracers of secondary organic aerosols. However, recent studies have reported their potential chemical instability, which is dependent on their structures. In this study, we aim to investigate the transformation and kinetics of a long-chain alkyl OS upon heterogeneous hydroxyl radical (OH) oxidation. We selected sodium dodecyl sulfate (SDS, C\u2081\u2082H\u2082\u2085O\u2084SNa) as a model compound due to its atmospheric relevance. We conducted experiments using an oxidation flow reactor at 80% RH and room temperature. We analyzed the reaction kinetics and products by liquid chromatography-mass spectrometry and ultrahigh-resolution mass spectrometry. We quantified inorganic sulfate formation by ion chromatography. We have proposed reaction pathways based on aerosol composition data. Our results reveal that dodecyl sulfate decays at (4.09 \u00b1 0.09) \u00d7 10\u207b\u00b9\u00b3 cm\u00b3 per molecule per s with an atmospheric lifetime of \u223c19 days upon heterogeneous OH oxidation. Compared with the literature results, we observe a significant kinetics enhancement when ammonium sulfate is present in aerosols. Our molecular dynamics simulations suggest that ammonium ions tend to displace sodium ions from the air\u2013water interface and attract OH more strongly, which promotes collisions between dodecyl OS and OH. Therefore, the effects of counterions on surface-active organics should be considered during interpretation of experimental kinetics data. We detected sequential oxygenation of dodecyl sulfate, which dominated over fragmentation and inorganic sulfate formation. Our identified products indicate a potential source of some oxygenated aliphatic C\u2086- to C\u2081\u2080- and C\u2081\u2082-OS detected in the atmosphere. Collectively, our work highlights the need for more comprehensive investigations of structural factors governing OS chemistry.", "doi": "10.1039/d2ea00026a", "issn": "2634-3606", "publisher": "Royal Society of Chemistry", "publication": "Environmental Science: Atmospheres", "publication_date": "2022-06-01", "series_number": "5", "volume": "2", "issue": "5", "pages": "1060-1075" }, { "id": "authors:tsv99-sn952", "collection": "authors", "collection_id": "tsv99-sn952", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130923-142910735", "type": "article", "title": "Secondary organic aerosol formation from biomass burning intermediates: phenol and methoxyphenols", "author": [ { "family_name": "Yee", "given_name": "L. D.", "orcid": "0000-0001-8965-9319", "clpid": "Yee-Lindsay-D" }, { "family_name": "Kautzman", "given_name": "K. E.", "clpid": "Kautzman-K-E" }, { "family_name": "Loza", "given_name": "C. L.", "clpid": "Loza-Christine-L" }, { "family_name": "Schilling", "given_name": "K. A.", "clpid": "Schilling-Katherine-A" }, { "family_name": "Coggon", "given_name": "M. M.", "orcid": "0000-0002-5763-1925", "clpid": "Coggon-Matthew-M" }, { "family_name": "Chhabra", "given_name": "P. S.", "clpid": "Chhabra-Puneet-S" }, { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Chan", "given_name": "A. W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Hersey", "given_name": "S. P.", "clpid": "Hersey-Scott-P" }, { "family_name": "Crounse", "given_name": "J. D.", "orcid": "0000-0001-5443-729X", "clpid": "Crounse-John-D" }, { "family_name": "Wennberg", "given_name": "P. O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" }, { "family_name": "Flagan", "given_name": "R. C.", "orcid": "0000-0001-5690-770X", "clpid": "Flagan-R-C" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "The formation of secondary organic aerosol from oxidation of phenol, guaiacol (2-methoxyphenol), and syringol (2,6-dimethoxyphenol), major components of biomass burning, is described. Photooxidation experiments were conducted in the Caltech laboratory chambers under low-NO\u2093 (< 10 ppb) conditions using H\u2082O\u2082 as the OH source. Secondary organic aerosol (SOA) yields (ratio of mass of SOA formed to mass of primary organic reacted) greater than 25% are observed. Aerosol growth is rapid and linear with the primary organic conversion, consistent with the formation of essentially non-volatile products. Gas- and aerosol-phase oxidation products from the guaiacol system provide insight into the chemical mechanisms responsible for SOA formation. Syringol SOA yields are lower than those of phenol and guaiacol, likely due to novel methoxy group chemistry that leads to early fragmentation in the gas-phase photooxidation. Atomic oxygen to carbon (O : C) ratios calculated from high-resolution-time-of-flight Aerodyne Aerosol Mass Spectrometer (HR-ToF-AMS) measurements of the SOA in all three systems are ~ 0.9, which represent among the highest such ratios achieved in laboratory chamber experiments and are similar to that of aged atmospheric organic aerosol. The global contribution of SOA from intermediate volatility and semivolatile organic compounds has been shown to be substantial (Pye and Seinfeld, 2010). An approach to representing SOA formation from biomass burning emissions in atmospheric models could involve one or more surrogate species for which aerosol formation under well-controlled conditions has been quantified. The present work provides data for such an approach.", "doi": "10.5194/acp-13-8019-2013", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2013-08-21", "series_number": "16", "volume": "13", "issue": "16", "pages": "8019-8043" }, { "id": "authors:25v7m-rgx27", "collection": "authors", "collection_id": "25v7m-rgx27", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130605-102705637", "type": "article", "title": "Oligomeric products and formation mechanisms from acid-catalyzed reactions of methyl vinyl ketone on acidic sulfate particles", "author": [ { "family_name": "Chan", "given_name": "Ka Man", "clpid": "Chan-Ka-Man" }, { "family_name": "Huang", "given_name": "Dan Dan", "clpid": "Huagn-Dan-Dan" }, { "family_name": "Li", "given_name": "Yong Jie", "clpid": "Li-Yong-Jie" }, { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Seinfeld", "given_name": "John H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" }, { "family_name": "Chan", "given_name": "Chak K.", "orcid": "0000-0001-9687-8771", "clpid": "Chan-Chak-Keung" } ], "abstract": "Methyl vinyl ketone (MVK) is a key first-generation product from atmospheric isoprene photo-oxidation, especially under high-NOx conditions. In this work, acid-catalyzed reactions of gas-phase MVK with ammonium sulfate (AS), ammonium bisulfate (ABS), and sulfuric acid (SA) particles were investigated in a flow reaction system at relative humidity (RH) of 40 % and 80 %. Ultra-performance liquid chromatography with electrospray ionization time-of-flight mass spectrometry (UPLC/ESI-TOFMS) and gas chromatography-mass spectrometry (GC-MS) are utilized to identify particle-phase products for developing the reaction mechanisms. High-order oligomers such as dimers and tetramers were detected when ABS and SA particles were used, while no oligomeric products were found when AS particles were used. Particle-phase oligomeric products were formed via i) acid-catalyzed aldol reaction with or without dehydration and/or ii) acid-catalyzed hydration followed by oligomerization. Reactions on SA particles yield more abundant and higher-order oligomers up to hexamers than on ABS particles. Moreover, aldol reaction occurred only on SA particles, but hydration followed by oligomerization occurred in both ABS and SA particles. The high RH condition with the same type of acidic particles was found to favor hydration and facilitate the subsequent oligomerization, while the low RH condition with the same type of acidic particles was found to favor aldol reaction with dehydration (aldol condensation). Overall, the findings suggest acidic particles can facilitate the formation of high-order oligomers in the particle phase, with particle acidity and RH as key factors.", "doi": "10.1007/s10874-013-9248-7", "issn": "0167-7764", "publisher": "Springer", "publication": "Journal of Atmospheric Chemistry", "publication_date": "2013-03", "series_number": "1", "volume": "70", "issue": "1", "pages": "1-18" }, { "id": "authors:bw7cf-g7881", "collection": "authors", "collection_id": "bw7cf-g7881", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121005-124120015", "type": "article", "title": "\u03b1-pinene photooxidation under controlled chemical conditions \u2013 Part 2: SOA yield and composition in low- and high-NO\u2093 environments", "author": [ { "family_name": "Eddingsaas", "given_name": "N. C.", "orcid": "0000-0003-1539-5415", "clpid": "Eddingsaas-Nathan-C" }, { "family_name": "Loza", "given_name": "C. L.", "clpid": "Loza-Christine-L" }, { "family_name": "Yee", "given_name": "L. D.", "orcid": "0000-0001-8965-9319", "clpid": "Yee-Lindsay-D" }, { "family_name": "Chan", "given_name": "M.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Schilling", "given_name": "K. A.", "clpid": "Schilling-Katherine-A" }, { "family_name": "Chhabra", "given_name": "P. S.", "clpid": "Chhabra-Puneet-S" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" }, { "family_name": "Wennberg", "given_name": "P. O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" } ], "abstract": "The gas-phase oxidation of \u03b1-pinene produces a large amount of secondary organic aerosol (SOA) in the atmosphere. A number of carboxylic acids, organosulfates and nitrooxy organosulfates associated with \u03b1-pinene have been found in field samples and some are used as tracers of \u03b1-pinene oxidation. \u03b1-pinene reacts readily with OH and O\u2083 in the atmosphere followed by reactions with both HO\u2082 and NO. Due to the large number of potential reaction pathways, it can be difficult to determine what conditions lead to SOA. To better understand the SOA yield and chemical composition from low- and high-NO\u2093 OH oxidation of \u03b1-pinene, studies were conducted in the Caltech atmospheric chamber under controlled chemical conditions. Experiments used low O\u2083 concentrations to ensure that OH was the main oxidant and low \u03b1-pinene concentrations such that the peroxy radical (RO\u2082) reacted primarily with either HO\u2082 under low-NO\u2093 conditions or NO under high-NO\u2093 conditions. SOA yield was suppressed under conditions of high-NO\u2093. SOA yield under high-NO\u2093 conditions was greater when ammonium sulfate/sulfuric acid seed particles (highly acidic) were present prior to the onset of growth than when ammonium sulfate seed particles (mildly acidic) were present; this dependence was not observed under low-NO\u2093 conditions. When aerosol seed particles were introduced after OH oxidation, allowing for later generation species to be exposed to fresh inorganic seed particles, a number of low-NO\u2093 products partitioned to the highly acidic aerosol. This indicates that the effect of seed acidity and SOA yield might be under-estimated in traditional experiments where aerosol seed particles are introduced prior to oxidation. We also identify the presence of a number of carboxylic acids that are used as tracer compounds of \u03b1-pinene oxidation in the field as well as the formation of organosulfates and nitrooxy organosulfates. A number of the carboxylic acids were observed under all conditions, however, pinic and pinonic acid were only observed under low-NO\u2093 conditions. Evidence is provided for particle-phase sulfate esterification of multi-functional alcohols.", "doi": "10.5194/acp-12-7413-2012", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2012-08-16", "series_number": "16", "volume": "12", "issue": "16", "pages": "7413-7427" }, { "id": "authors:83ngk-7x212", "collection": "authors", "collection_id": "83ngk-7x212", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20111128-115220934", "type": "article", "title": "Measurements of Isoprene-Derived Organosulfates in Ambient\n Aerosols by Aerosol Time-of-Flight Mass Spectrometry\u2014Part 2:\n Temporal Variability and Formation Mechanisms", "author": [ { "family_name": "Hatch", "given_name": "Lindsay E.", "orcid": "0000-0001-9037-9760", "clpid": "Hatch-Lindsay-E" }, { "family_name": "Creamean", "given_name": "Jessie M.", "orcid": "0000-0003-3819-5600", "clpid": "Creamean-Jessie-M" }, { "family_name": "Ault", "given_name": "Andrew P.", "orcid": "0000-0002-7313-8559", "clpid": "Ault-Andrew-P" }, { "family_name": "Surratt", "given_name": "Jason D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Seinfeld", "given_name": "John H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" }, { "family_name": "Edgerton", "given_name": "Eric S.", "clpid": "Edgerton-Eric-S" }, { "family_name": "Su", "given_name": "Yongxuan", "clpid": "Su-Yongxuan" }, { "family_name": "Prather", "given_name": "Kimberly A.", "orcid": "0000-0003-3048-9890", "clpid": "Prather-Kimberly-A" } ], "abstract": "Organosulfate species have recently gained attention for their potentially significant contribution to secondary organic aerosol (SOA); however, their temporal behavior in the ambient atmosphere has not been probed in detail. In this work, organosulfates derived from isoprene were observed in single particle mass spectra in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Real-time measurements revealed that the highest organosulfate concentrations occurred at night under a stable boundary layer, suggesting gas-to-particle partitioning and subsequent aqueous-phase processing of the organic precursors played key roles in their formation. Further analysis of the diurnal profile suggests possible contributions from multiple production mechanisms, including acid-catalysis and radical-initiation. This work highlights the potential for additional SOA formation pathways in biogenically influenced urban regions to enhance the organic aerosol burden.", "doi": "10.1021/es2011836", "issn": "0013-936X", "publisher": "American Chemical Society", "publication": "Environmental Science and Technology", "publication_date": "2011-10-15", "series_number": "20", "volume": "45", "issue": "20", "pages": "8648-8655" }, { "id": "authors:e9cd9-yg775", "collection": "authors", "collection_id": "e9cd9-yg775", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110906-153541149", "type": "article", "title": "The Pasadena Aerosol Characterization Observatory (PACO): chemical and physical analysis of the Western Los Angeles basin aerosol", "author": [ { "family_name": "Hersey", "given_name": "S. P.", "clpid": "Hersey-S-P" }, { "family_name": "Craven", "given_name": "J. S.", "clpid": "Craven-J-S" }, { "family_name": "Schilling", "given_name": "K. A.", "clpid": "Schilling-K-A" }, { "family_name": "Metcalf", "given_name": "A. R.", "orcid": "0000-0003-0385-1356", "clpid": "Metcalf-A-R" }, { "family_name": "Sorooshian", "given_name": "A.", "orcid": "0000-0002-2243-2264", "clpid": "Sorooshian-A" }, { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Flagan", "given_name": "R. C.", "orcid": "0000-0001-5690-770X", "clpid": "Flagan-R-C" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "The Pasadena Aerosol Characterization Observatory (PACO) represents the first major aerosol characterization experiment centered in the Western/Central Los Angeles Basin. The sampling site, located on the campus of the California Institute of Technology in Pasadena, was positioned to sample a continuous afternoon influx of transported urban aerosol with a photochemical age of 1\u20132 h and generally free from major local contributions. Sampling spanned 5 months during the summer of 2009, which were broken into 3 regimes on the basis of distinct meteorological conditions. Regime I was characterized by a series of low pressure systems, resulting in high humidity and rainy periods with clean conditions. Regime II typified early summer meteorology, with significant morning marine layers and warm, sunny afternoons. Regime III was characterized by hot, dry conditions with little marine layer influence. Regardless of regime, organic aerosol (OA) is the most significant constituent of nonrefractory submicron Los Angeles aerosol (42, 43, and 55 % of total submicron mass in regimes I, II, and III, respectively). The overall oxidation state remains relatively constant on timescales of days to weeks (O:C = 0.44 \u00b1 0.08, 0.55 \u00b1 0.05, and 0.48 \u00b1 0.08 during regimes I, II, and III, respectively), with no difference in O:C between morning and afternoon periods. Periods characterized by significant morning marine layer influence followed by photochemically favorable afternoons displayed significantly higher aerosol mass and O:C ratio, suggesting that aqueous processes may be important in the generation of secondary aerosol and oxidized organic aerosol (OOA) in Los Angeles. Online analysis of water soluble organic carbon (WSOC) indicates that water soluble organic mass (WSOM) reaches maxima near 14:00\u201315:00 local time (LT), but the percentage of AMS organic mass contributed by WSOM remains relatively constant throughout the day. Sulfate and nitrate reside predominantly in accumulation mode aerosol, while afternoon SOA production coincides with the appearance of a distinct fine mode dominated by organics. Particulate NH_4NO_3 and (NH_4)_2SO_4 appear to be NH_3-limited in regimes I and II, but a significant excess of particulate NH_4^+ in the hot, dry regime III suggests less SO_4^(2\u2212) and the presence of either organic amines or NH_4^+-associated organic acids. C-ToF-AMS data were analyzed by Positive Matrix Factorization (PMF), which resolved three factors, corresponding to a hydrocarbon-like OA (HOA), semivolatile OOA (SV-OOA), and low-volatility OOA (LV-OOA). HOA appears to be a periodic plume source, while SV-OOA exhibits a strong diurnal pattern correlating with ozone. Peaks in SV-OOA concentration correspond to peaks in DMA number concentration and the appearance of a fine organic mode. LV-OOA appears to be an aged accumulation mode constituent that may be associated with aqueous-phase processing, correlating strongly with sulfate and representing the dominant background organic component. Periods characterized by high SV-OOA and LV-OOA were analyzed by filter analysis, revealing a complex mixture of species during periods dominated by SV-OOA and LV-OOA, with LV-OOA periods characterized by shorter-chain dicarboxylic acids (higher O:C ratio), as well as appreciable amounts of nitrate- and sulfate-substituted organics. Phthalic acid was ubiquitous in filter samples, suggesting that PAH photochemistry may be an important SOA pathway in Los Angeles. Aerosol composition was related to water uptake characteristics, and it is concluded that hygroscopicity is largely controlled by organic mass fraction (OMF). The hygroscopicity parameter \u03ba averaged 0.31 \u00b1 0.08, approaching 0.5 at low OMF and 0.1 at high OMF, with increasing OMF suppressing hygroscopic growth and increasing critical dry diameter for CCN activation (D_d). An experiment-averaged \u03ba_(org) of 0.14 was calculated, indicating that the highly-oxidized organic fraction of aerosol in Los Angeles is appreciably more hygroscopic than previously reported in urban areas. Finally, PACO will provide context for results forthcoming from the CalNex field campaign, which involved ground sampling in Pasadena during the spring and summer of 2010.", "doi": "10.5194/acp-11-7417-2011", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2011-08-01", "series_number": "15", "volume": "11", "issue": "15", "pages": "7417-7443" }, { "id": "authors:j785y-qbt15", "collection": "authors", "collection_id": "j785y-qbt15", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110628-111859989", "type": "article", "title": "Measurements of Isoprene-Derived Organosulfates in Ambient\n Aerosols by Aerosol Time-of-Flight Mass Spectrometry - Part 1:\n Single Particle Atmospheric Observations in Atlanta", "author": [ { "family_name": "Hatch", "given_name": "Lindsay E.", "orcid": "0000-0001-9037-9760", "clpid": "Hatch-Lindsay-E" }, { "family_name": "Creamean", "given_name": "Jessie M.", "orcid": "0000-0003-3819-5600", "clpid": "Creamean-Jessie-M" }, { "family_name": "Ault", "given_name": "Andrew P.", "orcid": "0000-0002-7313-8559", "clpid": "Ault-Andrew-P" }, { "family_name": "Surratt", "given_name": "Jason D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Seinfeld", "given_name": "John H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" }, { "family_name": "Edgerton", "given_name": "Eric S.", "clpid": "Edgerton-Eric-S" }, { "family_name": "Su", "given_name": "Yongxuan", "clpid": "Su-Yongxuan" }, { "family_name": "Prather", "given_name": "Kimberly A.", "orcid": "0000-0003-3048-9890", "clpid": "Prather-Kimberly-A" } ], "abstract": "Organosulfate species have recently been identified as a potentially significant class of secondary organic aerosol (SOA) species, yet little is known about their behavior in the atmosphere. In this work, organosulfates were observed in individual ambient aerosols using single particle mass spectrometry in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Organosulfates derived from biogenically produced isoprene were detected as deprotonated molecular ions in negative-ion spectra measured by aerosol time-of-flight mass spectrometry; comparison to high-resolution mass spectrometry data obtained from filter samples corroborated the peak assignments. The size-resolved chemical composition measurements revealed that organosulfate species were mostly detected in submicrometer aerosols and across a range of aerosols from different sources, consistent with secondary reaction products. Detection of organosulfates in a large fraction of negative-ion ambient spectra \u2212 ca. 90\u221295% during ANARChE and ~65% of submicrometer particles in AMIGAS \u2212 highlights the ubiquity of organosulfate species in the ambient aerosols of biogenically influenced urban environments.", "doi": "10.1021/es103944a", "issn": "0013-936X", "publisher": "American Chemical Society", "publication": "Environmental Science and Technology", "publication_date": "2011-06-15", "series_number": "12", "volume": "45", "issue": "12", "pages": "5105-5111" }, { "id": "authors:wmwcp-wzr67", "collection": "authors", "collection_id": "wmwcp-wzr67", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110404-100259820", "type": "article", "title": "Influence of aerosol acidity on the chemical composition of secondary organic aerosol from \u03b2-caryophyllene", "author": [ { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Surratt", "given_name": "J. D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "A. W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Schilling", "given_name": "K.", "clpid": "Schilling-Katherine-A" }, { "family_name": "Offenberg", "given_name": "John H.", "orcid": "0000-0002-0213-4024", "clpid": "Offenberg-John-H" }, { "family_name": "Lewandowski", "given_name": "M.", "orcid": "0000-0002-0058-956X", "clpid": "Lewandowski-Michael" }, { "family_name": "Edney", "given_name": "E. O.", "clpid": "Edney-Edward-O" }, { "family_name": "Kleindienst", "given_name": "T. E.", "orcid": "0000-0002-3024-1564", "clpid": "Kleindienst-Tadeusz-E" }, { "family_name": "Jaoui", "given_name": "M.", "orcid": "0000-0002-2728-9137", "clpid": "Jaoui-Mohammed" }, { "family_name": "Edgerton", "given_name": "E. S.", "clpid": "Edgerton-Eric-S" }, { "family_name": "Tanner", "given_name": "R. L.", "clpid": "Tanner-Roger-L" }, { "family_name": "Shaw", "given_name": "S. L.", "orcid": "0000-0001-8198-4184", "clpid": "Shaw-Stephanie-L" }, { "family_name": "Zheng", "given_name": "M.", "clpid": "Zheng-Mei" }, { "family_name": "Knipping", "given_name": "E. M.", "orcid": "0000-0002-9654-9019", "clpid": "Knipping-Eladio-M" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "The secondary organic aerosol (SOA) yield of \u03b2-caryophyllene photooxidation is enhanced by aerosol acidity. In the present study, the influence of aerosol acidity on the chemical composition of \u03b2-caryophyllene SOA is investigated using ultra performance liquid chromatography/electrospray ionization-time-of-flight mass spectrometry (UPLC/ESI-TOFMS). A number of first-, second- and higher-generation gas-phase products having carbonyl and carboxylic acid functional groups are detected in the particle phase. Particle-phase reaction products formed via hydration and organosulfate formation processes are also detected. Increased acidity leads to different effects on the abundance of individual products; significantly, abundances of organosulfates are correlated with aerosol acidity. To our knowledge, this is the first detection of organosulfates and nitrated organosulfates derived from a sesquiterpene. The increase of certain particle-phase reaction products with increased acidity provides chemical evidence to support the acid-enhanced SOA yields. Based on the agreement between the chromatographic retention times and accurate mass measurements of chamber and field samples, three \u03b2-caryophyllene products (i.e., \u03b2-nocaryophyllon aldehyde, \u03b2-hydroxynocaryophyllon aldehyde, and \u03b2-dihydroxynocaryophyllon aldehyde) are suggested as chemical tracers for \u03b2-caryophyllene SOA. These compounds are detected in both day and night ambient samples collected in downtown Atlanta, GA and rural Yorkville, GA during the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS).", "doi": "10.5194/acp-11-1735-2011", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2011-02-25", "series_number": "4", "volume": "11", "issue": "4", "pages": "1735-1751" }, { "id": "authors:pdk4n-mep40", "collection": "authors", "collection_id": "pdk4n-mep40", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100915-133230350", "type": "article", "title": "Role of aldehyde chemistry and NO_x concentrations in secondary organic aerosol formation", "author": [ { "family_name": "Chan", "given_name": "A. W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Surratt", "given_name": "J. D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chhabra", "given_name": "P. S.", "clpid": "Chhabra-Puneet-S" }, { "family_name": "Loza", "given_name": "C. L.", "clpid": "Loza-Christine-L" }, { "family_name": "Crounse", "given_name": "J. D.", "orcid": "0000-0001-5443-729X", "clpid": "Crounse-John-D" }, { "family_name": "Yee", "given_name": "L. D.", "orcid": "0000-0001-8965-9319", "clpid": "Yee-Lindsay-D" }, { "family_name": "Flagan", "given_name": "R. C.", "orcid": "0000-0001-5690-770X", "clpid": "Flagan-R-C" }, { "family_name": "Wennberg", "given_name": "P. O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene), the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA) via methacrolein (a C_4-unsaturated aldehyde) under urban high-NO_x conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN) as the important intermediate to isoprene and methacrolein SOA in this NO_x regime. Here we show that as a result of this chemistry, NO_2 enhances SOA formation from methacrolein and two other \u03b1, \u03b2-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NO_x effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO_2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are \u03b1, \u03b2-unsaturated and contain an additional methyl group on the \u03b1-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232) is insignificant, even under high-NO_2 conditions, as PAN (peroxy acyl nitrate, RC(O)OONO_2) formation is structurally unfavorable. At atmospherically relevant NO_2/NO ratios (3\u20138), the SOA yields from isoprene high-NO_x photooxidation are 3 times greater than previously measured at lower NO_2/NO ratios. At sufficiently high NO_2 concentrations, in systems of \u03b1, \u03b2-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO_2 can exceed that from RO_2+HO_2 reactions under the same inorganic seed conditions, making RO_2+NO_2 an important channel for SOA formation.", "doi": "10.5194/acp-10-7169-2010", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2010-08-04", "series_number": "15", "volume": "10", "issue": "15", "pages": "7169-7188" }, { "id": "authors:6707x-9x778", "collection": "authors", "collection_id": "6707x-9x778", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100706-092745845", "type": "article", "title": "Characterization and Quantification of Isoprene-Derived Epoxydiols in Ambient Aerosol in the Southeastern United States", "author": [ { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Surratt", "given_name": "Jason D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Claeys", "given_name": "Magda", "orcid": "0000-0003-2278-8014", "clpid": "Claeys-Magda" }, { "family_name": "Edgerton", "given_name": "Eric S.", "clpid": "Edgerton-Eric-S" }, { "family_name": "Tanner", "given_name": "Roger L.", "clpid": "Tanner-Roger-L" }, { "family_name": "Shaw", "given_name": "Stephanie L.", "orcid": "0000-0001-8198-4184", "clpid": "Shaw-Stephanie-L" }, { "family_name": "Zheng", "given_name": "Mei", "clpid": "Zheng-Mei" }, { "family_name": "Knipping", "given_name": "Eladio M.", "orcid": "0000-0002-9654-9019", "clpid": "Knipping-Eladio-M" }, { "family_name": "Eddingsaas", "given_name": "Nathan C.", "orcid": "0000-0003-1539-5415", "clpid": "Eddingsaas-Nathan-C" }, { "family_name": "Wennberg", "given_name": "Paul O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" }, { "family_name": "Seinfeld", "given_name": "John H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "Isoprene-derived epoxydiols (IEPOX) are identified in ambient aerosol samples for the first time, together with other previously identified isoprene tracers (i.e., 2-methyltetrols, 2-methylglyceric acid, C5-alkenetriols, and organosulfate derivatives of 2-methyltetrols). Fine ambient aerosol collected in downtown Atlanta, GA and rural Yorkville, GA during the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS) was analyzed using both gas chromatography/quadrupole mass spectrometry (GC/MS) and gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) with prior trimethylsilylation. Mass concentrations of IEPOX ranged from ~1 to 24 ng m^(\u22123) in the aerosol collected from the two sites. Detection of particle-phase IEPOX in the AMIGAS samples supports recent laboratory results that gas-phase IEPOX produced from the photooxidation of isoprene under low-NO_x conditions is a key precursor of ambient isoprene secondary organic aerosol (SOA) formation. On average, the sum of the mass concentrations of IEPOX and the measured isoprene SOA tracers accounted for about 3% of the organic carbon, demonstrating the significance of isoprene oxidation to the formation of ambient aerosol in this region.", "doi": "10.1021/es100596b", "issn": "0013-936X", "publisher": "American Chemical Society", "publication": "Environmental Science and Technology", "publication_date": "2010-06-15", "series_number": "12", "volume": "44", "issue": "12", "pages": "4590-4596" }, { "id": "authors:e66z7-kgq86", "collection": "authors", "collection_id": "e66z7-kgq86", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100706-091228446", "type": "article", "title": "Evidence for High Molecular Weight Nitrogen-Containing Organic Salts in Urban Aerosols", "author": [ { "family_name": "Wang", "given_name": "Xiaofei", "clpid": "Wang-Xiaofei" }, { "family_name": "Gao", "given_name": "Song", "orcid": "0000-0001-7427-6681", "clpid": "Gao-Song" }, { "family_name": "Yang", "given_name": "Xing", "clpid": "Yang-Xing" }, { "family_name": "Chen", "given_name": "Hong", "clpid": "Chen-Hong" }, { "family_name": "Chen", "given_name": "Jianmin", "orcid": "0000-0001-5859-3070", "clpid": "Chen-Jianmin" }, { "family_name": "Zhuang", "given_name": "Guoshun", "clpid": "Zhuang-Guoshun" }, { "family_name": "Surratt", "given_name": "Jason D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Seinfeld", "given_name": "John H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "High molecular weight (M_w) species were observed at substantial intensities in the positive-ion mass spectra in urban Shanghai aerosols collected from a single-particle time-of-flight mass spectrometer (in the m/z range 250\u2212500) during three separate periods over 2007\u22122009. These species correlate well with the CN\u2212 mass signal, suggesting that C\u2212N bonds are prevalent and that the observed high-M_w species are potentially nitrogen-containing organic salts. Anti-correlation with the ambient O_3 concentration suggests that photochemical oxidants are not involved directly in the formation of these species. The Mannich reaction, among amines (or ammonia), formaldehyde, and carbonyls with an adjacent, acidic proton, is proposed as a plausible pathway leading to these organic salts. Although the high-M_w species observed in the single-particle mass spectra appear to be nitrogen-containing organics, further chemical confirmation is desired to verify if the proposed Mannich reaction can explain the formation of these high-M_w species in regions where ammonia, amines, and carbonyls are prevalent.", "doi": "10.1021/es1001117", "issn": "0013-936X", "publisher": "American Chemical Society", "publication": "Environmental Science and Technology", "publication_date": "2010-06-15", "series_number": "12", "volume": "44", "issue": "12", "pages": "4441-4446" }, { "id": "authors:r3zgd-5hq40", "collection": "authors", "collection_id": "r3zgd-5hq40", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100527-135521520", "type": "article", "title": "Reactive intermediates revealed in secondary organic aerosol formation from isoprene", "author": [ { "family_name": "Surratt", "given_name": "Jason D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "Arthur W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Eddingsaas", "given_name": "Nathan C.", "orcid": "0000-0003-1539-5415", "clpid": "Eddingsaas-Nathan-C" }, { "family_name": "Chan", "given_name": "ManNin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Loza", "given_name": "Christine L.", "clpid": "Loza-Christine-L" }, { "family_name": "Kwan", "given_name": "Alan J.", "clpid": "Kwan-Alan-J" }, { "family_name": "Hersey", "given_name": "Scott P.", "clpid": "Hersey-Scott-P" }, { "family_name": "Flagan", "given_name": "Richard C.", "orcid": "0000-0001-5690-770X", "clpid": "Flagan-R-C" }, { "family_name": "Wennberg", "given_name": "Paul O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" }, { "family_name": "Seinfeld", "given_name": "John H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "Isoprene is a significant source of atmospheric organic aerosol; however, the oxidation pathways that lead to secondary organic aerosol (SOA) have remained elusive. Here, we identify the role of two key reactive intermediates, epoxydiols of isoprene (IEPOX = \u03b2-IEPOX + \u03b4-IEPOX) and methacryloylperoxynitrate (MPAN), which are formed during isoprene oxidation under low- and high-NO_x conditions, respectively. Isoprene low-NO_x SOA is enhanced in the presence of acidified sulfate seed aerosol (mass yield 28.6%) over that in the presence of neutral aerosol (mass yield 1.3%). Increased uptake of IEPOX by acid-catalyzed particle-phase reactions is shown to explain this enhancement. Under high-NO_x conditions, isoprene SOA formation occurs through oxidation of its second-generation product, MPAN. The similarity of the composition of SOA formed from the photooxidation of MPAN to that formed from isoprene and methacrolein demonstrates the role of MPAN in the formation of isoprene high-NO_x SOA. Reactions of IEPOX and MPAN in the presence of anthropogenic pollutants (i.e., acidic aerosol produced from the oxidation of SO_2 and NO_2, respectively) could be a substantial source of \"missing urban SOA\" not included in current atmospheric models.", "doi": "10.1073/pnas.0911114107", "pmcid": "PMC2872383", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "2010-04-13", "series_number": "15", "volume": "107", "issue": "15", "pages": "6640-6645" }, { "id": "authors:q04wx-g1e86", "collection": "authors", "collection_id": "q04wx-g1e86", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100128-134602813", "type": "article", "title": "Chemical Composition of Gas- and Aerosol-Phase Products from the Photooxidation of Naphthalene", "author": [ { "family_name": "Kautzman", "given_name": "K.", "clpid": "Kautzman-K" }, { "family_name": "Surratt", "given_name": "J. D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Chan", "given_name": "A. W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Hersey", "given_name": "S. P.", "clpid": "Hersey-Scott-P" }, { "family_name": "Chhabra", "given_name": "P. S.", "clpid": "Chhabra-Puneet-S" }, { "family_name": "Dalleska", "given_name": "N. F.", "orcid": "0000-0002-2059-1587", "clpid": "Dalleska-Nathan-F" }, { "family_name": "Wennberg", "given_name": "P. O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" }, { "family_name": "Flagan", "given_name": "R. C.", "orcid": "0000-0001-5690-770X", "clpid": "Flagan-R-C" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "The current work focuses on the detailed evolution of the chemical composition of both the gas- and aerosol-phase constituents produced from the OH-initiated photooxidation of naphthalene under low- and high-NO\u2093 conditions. Under high-NO\u2093 conditions ring-opening products are the primary gas-phase products, suggesting that the mechanism involves dissociation of alkoxy radicals (RO) formed through an RO\u2082 + NO pathway, or a bicyclic peroxy mechanism. In contrast to the high-NO\u2093 chemistry, ring-retaining compounds appear to dominate the low-NO\u2093 gas-phase products owing to the RO\u2082 + HO\u2082 pathway. We are able to chemically characterize 53\u221268% of the secondary organic aerosol (SOA) mass. Atomic oxygen-to-carbon (O/C), hydrogen-to-carbon (H/C), and nitrogen-to-carbon (N/C) ratios measured in bulk samples by high-resolution electrospray ionization time-of-flight mass spectrometry (HR-ESI-TOFMS) are the same as the ratios observed with online high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS), suggesting that the chemical compositions and oxidation levels found in the chemically-characterized fraction of the particle phase are representative of the bulk aerosol. Oligomers, organosulfates (R-OSO\u2083), and other high-molecular-weight (MW) products are not observed in either the low- or high-NO\u2093 SOA; however, in the presence of neutral ammonium sulfate seed aerosol, an organic sulfonic acid (R-SO\u2083), characterized as hydroxybenzene sulfonic acid, is observed in naphthalene SOA produced under both high- and low-NO\u2093 conditions. Acidic compounds and organic peroxides are found to account for a large fraction of the chemically characterized high- and low-NO\u2093 SOA. We propose that the major gas- and aerosol-phase products observed are generated through the formation and further reaction of 2-formylcinnamaldehyde or a bicyclic peroxy intermediate. The chemical similarity between the laboratory SOA and ambient aerosol collected from Birmingham, Alabama (AL) and Pasadena, California (CA) confirm the importance of PAH oxidation in the formation of aerosol within the urban atmosphere.", "doi": "10.1021/jp908530s", "issn": "1089-5639", "publisher": "American Chemical Society", "publication": "Journal of Physical Chemistry A", "publication_date": "2010-01-21", "series_number": "2", "volume": "114", "issue": "2", "pages": "913-934" }, { "id": "authors:e949e-f0k31", "collection": "authors", "collection_id": "e949e-f0k31", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090826-112856345", "type": "article", "title": "Modeling of secondary organic aerosol yields from laboratory chamber data", "author": [ { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Chan", "given_name": "A. W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Chhabra", "given_name": "P. S.", "clpid": "Chhabra-Puneet-S" }, { "family_name": "Surratt", "given_name": "J. D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "Laboratory chamber data serve as the basis for constraining models of secondary organic aerosol (SOA) formation. Current models fall into three categories: empirical two-product (Odum), product-specific, and volatility basis set. The product-specific and volatility basis set models are applied here to represent laboratory data on the ozonolysis of \u03b1-pinene under dry, dark, and low-NOx conditions in the presence of ammonium sulfate seed aerosol. Using five major identified products, the model is fit to the chamber data. From the optimal fitting, SOA oxygen-to-carbon (O/C) and hydrogen-to-carbon (H/C) ratios are modeled. The discrepancy between measured H/C ratios and those based on the oxidation products used in the model fitting suggests the potential importance of particle-phase reactions. Data fitting is also carried out using the volatility basis set, wherein oxidation products are parsed into volatility bins. The product-specific model is most likely hindered by lack of explicit inclusion of particle-phase accretion compounds. While prospects for identification of the majority of SOA products for major volatile organic compounds (VOCs) classes remain promising, for the near future empirical product or volatility basis set models remain the approaches of choice.", "doi": "10.5194/acp-9-5669-2009", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2009-08-10", "series_number": "15", "volume": "9", "issue": "15", "pages": "5669-5680" }, { "id": "authors:y5jr4-rxn55", "collection": "authors", "collection_id": "y5jr4-rxn55", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090814-103729079", "type": "article", "title": "Secondary organic aerosol formation from photooxidation of naphthalene and alkylnaphthalenes: implications for oxidation of intermediate volatility organic compounds (IVOCs)", "author": [ { "family_name": "Chan", "given_name": "A. W. H.", "orcid": "0000-0001-7392-4237", "clpid": "Chan-Arthur-W-H" }, { "family_name": "Kautzman", "given_name": "K. E.", "clpid": "Kautzman-K-E" }, { "family_name": "Chhabra", "given_name": "P. S.", "clpid": "Chhabra-Puneet-S" }, { "family_name": "Surratt", "given_name": "J. D.", "orcid": "0000-0002-6833-1450", "clpid": "Surratt-Jason-D" }, { "family_name": "Chan", "given_name": "M. N.", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Crounse", "given_name": "J. D.", "orcid": "0000-0001-5443-729X", "clpid": "Crounse-John-D" }, { "family_name": "K\u00fcrten", "given_name": "A.", "orcid": "0000-0002-8955-4450", "clpid": "K\u00fcrten-Andreas" }, { "family_name": "Wennberg", "given_name": "P. O.", "orcid": "0000-0002-6126-3854", "clpid": "Wennberg-P-O" }, { "family_name": "Flagan", "given_name": "R. C.", "orcid": "0000-0001-5690-770X", "clpid": "Flagan-R-C" }, { "family_name": "Seinfeld", "given_name": "J. H.", "orcid": "0000-0003-1344-4068", "clpid": "Seinfeld-J-H" } ], "abstract": "Current atmospheric models do not include secondary organic aerosol (SOA) production from gas-phase reactions of polycyclic aromatic hydrocarbons (PAHs). Recent studies have shown that primary emissions undergo oxidation in the gas phase, leading to SOA formation. This opens the possibility that low-volatility gas-phase precursors are a potentially large source of SOA. In this work, SOA formation from gas-phase photooxidation of naphthalene, 1-methylnaphthalene (1-MN), 2-methylnaphthalene (2-MN), and 1,2-dimethylnaphthalene (1,2-DMN) is studied in the Caltech dual 28-m3 chambers. Under high-NOx conditions and aerosol mass loadings between 10 and 40 \u03bcg m\u22123, the SOA yields (mass of SOA per mass of hydrocarbon reacted) ranged from 0.19 to 0.30 for naphthalene, 0.19 to 0.39 for 1-MN, 0.26 to 0.45 for 2-MN, and constant at 0.31 for 1,2-DMN. Under low-NOx conditions, the SOA yields were measured to be 0.73, 0.68, and 0.58, for naphthalene, 1-MN, and 2-MN, respectively. The SOA was observed to be semivolatile under high-NOx conditions and essentially nonvolatile under low-NOx conditions, owing to the higher fraction of ring-retaining products formed under low-NOx conditions. When applying these measured yields to estimate SOA formation from primary emissions of diesel engines and wood burning, PAHs are estimated to yield 3\u20135 times more SOA than light aromatic compounds over photooxidation timescales of less than 12 h. PAHs can also account for up to 54% of the total SOA from oxidation of diesel emissions, representing a potentially large source of urban SOA.", "doi": "10.5194/acp-9-3049-2009", "issn": "1680-7316", "publisher": "European Geosciences Union", "publication": "Atmospheric Chemistry and Physics", "publication_date": "2009-05-12", "series_number": "9", "volume": "9", "issue": "9", "pages": "3049-3060" }, { "id": "authors:rbwcs-zna49", "collection": "authors", "collection_id": "rbwcs-zna49", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170315-125424636", "type": "article", "title": "Hygroscopicity of Water-Soluble Organic Compounds in Atmospheric Aerosols: Amino Acids and Biomass Burning Derived Organic Species", "author": [ { "family_name": "Chan", "given_name": "Man Nin", "orcid": "0000-0002-2384-2695", "clpid": "Chan-Man-Nin" }, { "family_name": "Choi", "given_name": "Man Yee", "clpid": "Choi-Man-Yee" }, { "family_name": "Ng", "given_name": "Nga Lee", "orcid": "0000-0001-8460-4765", "clpid": "Ng-Nga-Lee" }, { "family_name": "Chan", "given_name": "Chak K.", "orcid": "0000-0001-9687-8771", "clpid": "Chan-Chak-Keung" } ], "abstract": "Amino acids and organic species derived from biomass burning can potentially affect the hygroscopicity and cloud condensation activities of aerosols. The hygroscopicity of seven amino acids (glycine, alanine, serine, glutamine, threonine, arginine, and asparagine) and three organic species most commonly detected in biomass burning aerosols (levoglucosan, mannosan, and galactosan) were measured using an electrodynamic balance. Crystallization was observed in the glycine, alanine, serine, glutamine, and threonine particles upon evaporation of water, while no phase transition was observed in the arginine and asparagine particles even at 5% relative humidity (RH). Water activity data from these aqueous amino acid particles, except arginine and asparagine, was used to revise the interaction parameters in UNIQUAC functional group activity coefficients to give predictions to within 15% of the measurements. Levoglucosan, mannosan, and galactosan particles did not crystallize nor did they deliquesce. They existed as highly concentrated liquid droplets at low RH, suggesting that biomass burning aerosols retain water at low RH. In addition, these particles follow a very similar pattern in hygroscopic growth. A generalized growth law (G_f = (1 \u2212 RH/100)^(-0.095)) is proposed for levoglucosan, mannosan, and galactosan particles.", "doi": "10.1021/es049584l", "issn": "0013-936X", "publisher": "American Chemical Society", "publication": "Environmental Science and Technology", "publication_date": "2005-03-15", "series_number": "6", "volume": "39", "issue": "6", "pages": "1555-1562" } ]