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Gao Q, Shen C, Zhang H, Long B, Truhlar DG. Quantitative kinetics reveal that reactions of HO 2 are a significant sink for aldehydes in the atmosphere and may initiate the formation of highly oxygenated molecules via autoxidation. Phys Chem Chem Phys 2024; 26:16160-16174. [PMID: 38787752 DOI: 10.1039/d4cp00693c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2024]
Abstract
Large aldehydes are widespread in the atmosphere and their oxidation leads to secondary organic aerosols. The current understanding of their chemical transformation processes is limited to hydroxyl radical (OH) oxidation during daytime and nitrate radical (NO3) oxidation during nighttime. Here, we report quantitative kinetics calculations of the reactions of hexanal (C5H11CHO), pentanal (C4H9CHO), and butanal (C3H7CHO) with hydroperoxyl radical (HO2) at atmospheric temperatures and pressures. We find that neither tunneling nor multistructural torsion anharmonicity should be neglected in computing these rate constants; strong anharmonicity at the transition states is also important. We find rate constants for the three reactions in the range 3.2-7.7 × 10-14 cm3 molecule-1 s-1 at 298 K and 1 atm, showing that the HO2 reactions can be competitive with OH and NO3 oxidation under some conditions relevant to the atmosphere. Our findings reveal that HO2-initiated oxidation of large aldehydes may be responsible for the formation of highly oxygenated molecules via autoxidation. We augment the theoretic studies with laboratory flow-tube experiments using an iodide-adduct time-of-flight chemical ionization mass spectrometer to confirm the theoretical predictions of peroxy radicals and the autoxidation pathway. We find that the adduct from HO2 + C5H11CHO undergoes a fast unimolecular 1,7-hydrogen shift with a rate constant of 0.45 s-1. We suggest that the HO2 reactions make significant contributions to the sink of aldehydes.
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Affiliation(s)
- Qiao Gao
- School of Physics and Mechatronic Engineering, Guizhou Minzu University, Guiyang 550025, China.
| | - Chuanyang Shen
- Department of Chemistry, University of California, Riverside, California, 92507, USA.
| | - Haofei Zhang
- Department of Chemistry, University of California, Riverside, California, 92507, USA.
| | - Bo Long
- School of Physics and Mechatronic Engineering, Guizhou Minzu University, Guiyang 550025, China.
- College of Materials Science and Engineering, Guizhou Minzu university, Guiyang 550025, China
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, USA.
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2
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Klippenstein SJ, Elliott SN. OH Roaming during the Ozonolysis of α-Pinene: A New Route to Highly Oxygenated Molecules? J Phys Chem A 2023; 127:10647-10662. [PMID: 38055299 DOI: 10.1021/acs.jpca.3c05179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
The formation of low-volatility organic compounds in the ozonolysis of α-pinene, the dominant atmospheric monoterpene, provides an important route to aerosol formation. In this work, we consider a previously unexplored set of pathways for the formation of highly oxygenated molecules in α-pinene ozonolysis. Pioneering, direct experimental observations of Lester and co-workers have demonstrated a significant production of hydroxycarbonyl products in the dissociation of Criegee intermediates. Theoretical analyses indicate that this production arises from OH roaming-induced pathways during the OO fission of the vinylhydroperoxides (VHPs), which in turn come from internal H transfers in the Criegee intermediates. Ab initio kinetics computations are used here to explore the OH roaming-induced channels that arise from the ozonolysis of α-pinene. For computational reasons, the calculations consider a surrogate for α-pinene, where two spectator methyl groups are replaced with H atoms. Multireference electronic structure calculations are used to illustrate a variety of energetically accessible OH roaming pathways for the four VHPs arising from the ozonolysis of this α-pinene surrogate. Ab initio transition-state theory-based master equation calculations indicate that for the dissociation of stabilized VHPs, these OH roaming pathways are kinetically significant with a branching that generally increases from ∼20% at room temperature up to ∼70% at lower temperatures representative of the troposphere. For one of the VHPs, this branching already exceeds 60% at room temperature. For the overall ozonolysis process, these branching ratios would be greatly reduced by a limited branching to the stabilized VHP, although there would also be some modest roaming fraction for the nonthermal VHP dissociation process. The strong exothermicities of the roaming-induced isomerizations/additions and abstractions suggest new routes to fission of the cyclobutane rings. Such ring fissions would facilitate further autoxidation reactions, thereby providing a new route for producing highly oxygenated nonvolatile precursors to aerosol formation.
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Affiliation(s)
- Stephen J Klippenstein
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Sarah N Elliott
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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3
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Guo X, Chan YC, Gautam T, Zhao R. Autoxidation of glycols used in inhalable daily products: implications for the use of artificial fogs and e-cigarettes. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:1657-1669. [PMID: 37728872 DOI: 10.1039/d3em00214d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
The use of glycols is seen in various industries and occupations. In the past few decades, the health implications of inhalable glycols have gained public attention. Inhalable glycols may cause adverse health effects, especially for workers in occupations receiving frequent exposure and consumers of glycol-based daily products. Our previous work highlighted the rapid accumulation of formaldehyde and glycolaldehyde in fog juice, thus proposing the occurrence of glycol autoxidation. However, the fundamentals of glycol autoxidation remained unclear and unexplored. Our goal is to investigate the autoxidation of common glycols during indoor storage. Carbonyls were quantified using liquid chromatography-mass spectrometry (LC-MS), and peroxides from autoxidation were monitored via iodometry and UV-Vis spectrometry. The impact of certain factors such as the water mixing ratio and antioxidants (vitamin C) was also investigated. Formation of aldehydes in many glycols was weekly monitored, such as e-cigarette juice and triethylene glycol (TEG). Occurrence of autoxidation was confirmed by the increase in the total peroxide concentration. Additionally, we highlighted the dependence of the carbonyl formation rate on the TEG-water mixing ratio, demonstrating the complex role of water in glycol autoxidation. We have also tested the effectiveness of vitamin C and made suggestions for minimizing the formation of toxic carbonyls in consumer products.
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Affiliation(s)
- Xinyang Guo
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Ya-Chun Chan
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Tania Gautam
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada.
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4
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Lee WC, Liu P, Han Y, Martin ST, Kuwata M. Accounting for Cloud Nucleation Activation Mechanism of Secondary Organic Matter from α-Pinene Oxidation Using Experimentally Retrieved Water Solubility Distributions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13439-13448. [PMID: 37647587 DOI: 10.1021/acs.est.3c03039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Activation of cloud droplets of aerosol particles from biogenic precursors plays a critical role in Earth's climate system. However, the molecular-level understanding of the cloud condensation nuclei (CCN) activation process for secondary organic matter (SOM) is still lacking. Here, we reduced the gap by segregating SOM from α-pinene based on water solubility. The chemical composition and CCN activity of the solubility-segregated fractions of SOM were measured. The results demonstrated for the first time by laboratory experiment that highly oxygenated compounds such as hydroperoxides and highly oxygenated organic molecules are important contributors for the CCN activity of α-pinene SOM. Meanwhile, relatively less water-soluble species were also abundant. Analysis based on the Köhler theory demonstrated that less water-soluble compounds in SOM remain undissolved during the cloud activation process, suggesting that the traditional single-parameter parameterization for CCN activation would not be sufficient for representing the process. In combination with the recent developments in SOM formation chemistry, the present study helps in understanding the interactions between the biosphere and climate.
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Affiliation(s)
- Wen-Chien Lee
- Department of Atmospheric and Oceanic Sciences, Laboratory for Climate and Ocean-Atmosphere Studies, Peking University, Beijing 100871, China
- Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), Peking University, Beijing 100871, China
- Division of Chemistry and Biochemistry, Nanyang Technological University, Singapore 639798, Singapore
- Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798, Singapore
- John A. Paulson School of Environment and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Pengfei Liu
- John A. Paulson School of Environment and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Yuemei Han
- John A. Paulson School of Environment and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Scot T Martin
- John A. Paulson School of Environment and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
- Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Mikinori Kuwata
- Department of Atmospheric and Oceanic Sciences, Laboratory for Climate and Ocean-Atmosphere Studies, Peking University, Beijing 100871, China
- Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), Peking University, Beijing 100871, China
- Division of Chemistry and Biochemistry, Nanyang Technological University, Singapore 639798, Singapore
- Earth Observatory of Singapore, Nanyang Technological University, Singapore 639798, Singapore
- Campus for Research Excellence and Technological Enterprise (CREATE) Programme, Singapore 138602, Singapore
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Tiusanen A, Ruiz-Jimenez J, Hartonen K, Wiedmer SK. Analytical methodologies for oxidized organic compounds in the atmosphere. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:1263-1287. [PMID: 37491999 DOI: 10.1039/d3em00163f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/27/2023]
Abstract
Oxidized compounds in the atmosphere can occur as emitted primary compounds or as secondary products when volatile emitted precursors react with various oxidants. Due to the presence of polar functional groups, their vapor pressures decrease, and they condense onto small particles. Thereby, they have an effect on climate change by the formation of clouds and scattering solar radiation. The particles and oxidized compounds themselves can cause serious health problems when inhaled. Therefore, it is of utmost importance to study oxidized compounds in the atmosphere. Much ongoing research is focused on the discovery of new oxidized substances and on the evaluation of their sources and factors influencing their formation. Monitoring biogenic and anthropogenic primary oxidized compounds or secondary oxidized products in chamber experiments or field campaigns is common. New discoveries have been reported, including various oxidized compounds and a new group of compounds called highly oxidized organic molecules (HOMs). Analytics of HOMs are mainly focused on chromatography and high-resolution mass spectrometry employing chemical ionization for identifying and quantifying compounds at low concentrations. Oxidized compounds can also be monitored by spectrophotometric methods in which the determinations of total amounts are based on functional groups. This review highlights recent findings on oxidized organic compounds in the atmosphere and analytical methodologies used for their detection and quantification. The discussion includes gas and liquid chromatographic methods, sampling, extraction, concentration, and derivatization procedures involved, as well as mass spectrometric and spectrophotometric methods.
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Affiliation(s)
- Aleksi Tiusanen
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
| | - Jose Ruiz-Jimenez
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
- Institute for Atmospheric and Earth System Research, Chemistry, Faculty of Science, P.O. Box 55, FI-00014 University of Helsinki, Finland
| | - Kari Hartonen
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
- Institute for Atmospheric and Earth System Research, Chemistry, Faculty of Science, P.O. Box 55, FI-00014 University of Helsinki, Finland
| | - Susanne K Wiedmer
- Department of Chemistry, P.O. Box 55, FI-00014 University of Helsinki, Finland.
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6
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Upshur MA, Bé AG, Luo J, Varelas JG, Geiger FM, Thomson RJ. Organic synthesis in the study of terpene-derived oxidation products in the atmosphere. Nat Prod Rep 2023; 40:890-921. [PMID: 36938683 DOI: 10.1039/d2np00064d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
Abstract
Covering: 1997 up to 2022Volatile biogenic terpenes involved in the formation of secondary organic aerosol (SOA) particles participate in rich atmospheric chemistry that impacts numerous aspects of the earth's complex climate system. Despite the importance of these species, understanding their fate in the atmosphere and determining their atmospherically-relevant properties has been limited by the availability of authentic standards and probe molecules. Advances in synthetic organic chemistry directly aimed at answering these questions have, however, led to exciting discoveries at the interface of chemistry and atmospheric science. Herein we provide a review of the literature regarding the synthesis of commercially unavailable authentic standards used to analyze the composition, properties, and mechanisms of SOA particles in the atmosphere.
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Affiliation(s)
- Mary Alice Upshur
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA.
| | - Ariana Gray Bé
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA.
| | - Jingyi Luo
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA.
| | - Jonathan G Varelas
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA.
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA.
| | - Regan J Thomson
- Department of Chemistry, Northwestern University, 2145 Sheridan Rd, Evanston, IL 60208, USA.
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7
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West CP, Mesa Sanchez D, Morales AC, Hsu YJ, Ryan J, Darmody A, Slipchenko LV, Laskin J, Laskin A. Molecular and Structural Characterization of Isomeric Compounds in Atmospheric Organic Aerosol Using Ion Mobility-Mass Spectrometry. J Phys Chem A 2023; 127:1656-1674. [PMID: 36763810 DOI: 10.1021/acs.jpca.2c06459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Secondary organic aerosol (SOA) formed through multiphase atmospheric chemistry makes up a large fraction of airborne particles. The chemical composition and molecular structures of SOA constituents vary between different emission sources and aging processes in the atmosphere, which complicates their identification. In this work, we employ drift tube ion mobility spectrometry with quadrupole time-of-flight mass spectrometry (IM-MS) detection for rapid gas-phase separation and multidimensional characterization of isomers in two biogenic SOAs produced from ozonolysis of isomeric monoterpenes, d-limonene (LSOA) and α-pinene (PSOA). SOA samples were ionized using electrospray ionization (ESI) and characterized using IM-MS in both positive and negative ionization modes. The IM-derived collision cross sections in nitrogen gas (DTCCSN2 ) for individual SOA components were obtained using multifield and single-field measurements. A novel application of IM multiplexing/high-resolution demultiplexing methodology was employed to increase sensitivity, improve peak shapes, and augment mobility baseline resolution, which revealed several isomeric structures for the measured ions. For LSOA and PSOA samples, we report significant structural differences of the isomer structures. Molecular structural calculations using density functional theory combined with the theoretical modeling of CCS values provide insights into the structural differences between LSOA and PSOA constituents. The average DTCCSN2 values for monomeric SOA components observed as [M + Na]+ ions are 3-6% higher than those of their [M - H]- counterparts. Meanwhile, dimeric and trimeric isomer components in both samples showed an inverse trend with the relevant values of [M - H]- ions being 3-7% higher than their [M + Na]+ counterparts, respectively. The results indicate that the structures of Na+-coordinated oligomeric ions are more compact than those of the corresponding deprotonated species. The coordination with Na+ occurs on the oxygen atoms of the carbonyl groups leading to a compact configuration. Meanwhile, deprotonated molecules have higher DTCCSN2 values due to their elongated structures in the gas phase. Therefore, DTCCSN2 values of isomers in SOA mixtures depend strongly on the mode of ionization in ESI. Additionally, PSOA monomers and dimers exhibit larger DTCCSN2 values (1-4%) than their LSOA counterparts owing to more rigid structures. A cyclobutane ring is present with functional groups pointing in opposite directions in PSOA compounds, as compared to noncyclic flexible LSOA structures, forming more compact ions in the gas phase. Lastly, we investigated the effects of direct photolysis on the chemical transformations of selected individual PSOA components. We use IM-MS to reveal structural changes associated with aerosol aging by photolysis. This study illustrates the detailed molecular and structural descriptors for the detection and annotation of structural isomers in complex SOA mixtures.
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Affiliation(s)
- Christopher P West
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Daniela Mesa Sanchez
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Yun-Jung Hsu
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jackson Ryan
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Andrew Darmody
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.,Department of Aeronautics and Aerospace Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Lyudmila V Slipchenko
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Julia Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.,Department of Earth, Atmospheric & Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, United States
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8
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Wang S, Zhao Y, Chan AWH, Yao M, Chen Z, Abbatt JPD. Organic Peroxides in Aerosol: Key Reactive Intermediates for Multiphase Processes in the Atmosphere. Chem Rev 2023; 123:1635-1679. [PMID: 36630720 DOI: 10.1021/acs.chemrev.2c00430] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Organic peroxides (POs) are organic molecules with one or more peroxide (-O-O-) functional groups. POs are commonly regarded as chemically labile termination products from gas-phase radical chemistry and therefore serve as temporary reservoirs for oxidative radicals (HOx and ROx) in the atmosphere. Owing to their ubiquity, active gas-particle partitioning behavior, and reactivity, POs are key reactive intermediates in atmospheric multiphase processes determining the life cycle (formation, growth, and aging), climate, and health impacts of aerosol. However, there remain substantial gaps in the origin, molecular diversity, and fate of POs due to their complex nature and dynamic behavior. Here, we summarize the current understanding on atmospheric POs, with a focus on their identification and quantification, state-of-the-art analytical developments, molecular-level formation mechanisms, multiphase chemical transformation pathways, as well as environmental and health impacts. We find that interactions with SO2 and transition metal ions are generally the fast PO transformation pathways in atmospheric liquid water, with lifetimes estimated to be minutes to hours, while hydrolysis is particularly important for α-substituted hydroperoxides. Meanwhile, photolysis and thermolysis are likely minor sinks for POs. These multiphase PO transformation pathways are distinctly different from their gas-phase fates, such as photolysis and reaction with OH radicals, which highlights the need to understand the multiphase partitioning of POs. By summarizing the current advances and remaining challenges for the investigation of POs, we propose future research priorities regarding their origin, fate, and impacts in the atmosphere.
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Affiliation(s)
- Shunyao Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
- School of Environmental and Chemical Engineering, Shanghai University, Shanghai200444, China
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, OntarioM5S 3E5, Canada
| | - Yue Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Arthur W H Chan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, OntarioM5S 3E5, Canada
- School of the Environment, University of Toronto, Toronto, OntarioM5S 3E8, Canada
| | - Min Yao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai200240, China
| | - Zhongming Chen
- State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing100871, China
| | - Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, Toronto, OntarioM5S 3H6, Canada
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Tian L, Huang DD, Li YJ, Yan C, Nie W, Wang Z, Wang Q, Qiao L, Zhou M, Zhu S, Liu Y, Guo Y, Qiao X, Zheng P, Jing S, Lou S, Wang H, Huang C. Enigma of Urban Gaseous Oxygenated Organic Molecules: Precursor Type, Role of NO x, and Degree of Oxygenation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:64-75. [PMID: 36516990 DOI: 10.1021/acs.est.2c05047] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Oxidation of volatile organic compounds (VOCs) forms oxygenated organic molecules (OOMs), which contribute to secondary pollution. Herein, we present measurement results of OOMs using chemical ionization mass spectrometry with nitrate as the reagent ion in Shanghai. Compared to those in forests and laboratory studies, OOMs detected at this urban site were of relatively lower degree of oxygenation. This was attributed to the high NOx concentrations (∼44 ppb), which overall showed a suppression on the propagation reactions. As another result, a large fraction of nitrogenous OOMs (75%) was observed, and this fraction further increased to 84% under a high NO/VOC ratio. By applying a novel framework on OOM categorization and supported by VOC measurements, 50 and 32% OOMs were attributed to aromatic and aliphatic precursors, respectively. Furthermore, aromatic OOMs are more oxygenated (effective oxygen number, nOeff = 4-6) than aliphatic ones (nOeff = 3-4), which can be partly explained by the difference in initiation mechanisms and points to possible discrimination in termination reactions. This study highlights the roles of NOx in OOM formation in urban areas, as well as the formation of nitrogenous products that might show discrimination between aromatic and aliphatic VOCs.
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Affiliation(s)
- Linhui Tian
- Department of Civil and Environmental Engineering, and Centre for Regional Oceans, Faculty of Science and Technology, University of Macau, Macau, Taipa 999078, China
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Dan Dan Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yong Jie Li
- Department of Civil and Environmental Engineering, and Centre for Regional Oceans, Faculty of Science and Technology, University of Macau, Macau, Taipa 999078, China
| | - Chao Yan
- Aerosol and Haze Laboratory, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
| | - Wei Nie
- Joint International Research Laboratory of Atmospheric and Earth System Research, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
| | - Zhe Wang
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology (HKUST), Hong Kong SAR 999077, China
| | - Qian Wang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Liping Qiao
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Min Zhou
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Shuhui Zhu
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yuliang Liu
- Joint International Research Laboratory of Atmospheric and Earth System Research, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
| | - Yishuo Guo
- Aerosol and Haze Laboratory, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Xiaohui Qiao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, School of Environment, Tsinghua University, Beijing 100084, China
| | - Penggang Zheng
- Division of Environment and Sustainability, The Hong Kong University of Science and Technology (HKUST), Hong Kong SAR 999077, China
| | - Sheng'ao Jing
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Shengrong Lou
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Hongli Wang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Cheng Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
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10
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Verma SK, Biswas A, Saxena S, Kumar M, Mishra A, Choudhury AD, Mishra T, Rais N, Narender T, Bhatta RS. Development of a sensitive and selective bioanalytical method of chebulinic acid by liquid chromatography‐electrospray tandem mass spectrometry and its pharmacokinetic application. SEPARATION SCIENCE PLUS 2022. [DOI: 10.1002/sscp.202200125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Affiliation(s)
- Sarvesh Kumar Verma
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
- Jawaharlal Nehru University New Delhi India
| | - Arpon Biswas
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
- Jawaharlal Nehru University New Delhi India
| | - Shivani Saxena
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
| | - Mukesh Kumar
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
- Jawaharlal Nehru University New Delhi India
| | - Anjali Mishra
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
- Academy of Scientific and Innovative Research New Delhi India
| | - Abhijit Deb Choudhury
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
- Jawaharlal Nehru University New Delhi India
| | - Tripti Mishra
- Jawaharlal Nehru University New Delhi India
- Division of Medicinal and Process Chemistry CSIR‐Central Drug Research Institute Lucknow India
| | - Nisha Rais
- Division of Medicinal and Process Chemistry CSIR‐Central Drug Research Institute Lucknow India
| | - Tadigoppula Narender
- Division of Medicinal and Process Chemistry CSIR‐Central Drug Research Institute Lucknow India
| | - Rabi Sankar Bhatta
- Pharmaceutics and Pharmacokinetic Division CSIR‐Central Drug Research Institute Lucknow India
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11
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Shi X, Tang R, Dong Z, Liu H, Xu F, Zhang Q, Zong W, Cheng J. A neglected pathway for the accretion products formation in the atmosphere. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157494. [PMID: 35914590 DOI: 10.1016/j.scitotenv.2022.157494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/09/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
Highly oxygenated organic molecules (HOM) formed by the autoxidation of α-pinene initiated by OH radicals play an important role in new particle formation. It is believed that the accretion products, ROOR´, formed by the self- and cross-reaction of peroxy radicals (RO2 + R'O2 reactions), have extremely low volatility and are more likely to participate in nucleation. However, the mechanism of ROOR´ formation has not been fully demonstrated by experiment or theoretical calculation. Herein, we propose a novel mechanism of RO2 reacting with α-pinene (RO2 + α-pinene reactions) that have much lower potential barriers and larger rate constants than the reaction of RO2 with R'O2, which explains the ROOR´ formation found in the mass spectrometry experiments. The ROOR´ resulting from the reaction of RO2 with α-pinene can produce HOM dimers and trimers with a higher oxygen-to‑carbon (O/C) ratio through a autoxidation chain. We also demonstrated that the presence of NOx and HO2 radical will reduce the RO2 concentration, but cannot completely inhibit the formation of HOM monomers and ROOR´. Even if one or both of RO2 radicals are acyl peroxy radicals (RC(O)O2), the potential barriers of the reactions between RC(O)O2 and α-pinene (RC(O)O2 + α-pinene reactions) are lower than that of RO2 reacting with RC(O)O2 (RO2 + RC(O)O2 reactions) or RC(O)O2 self-reactions (RC(O)O2 + RC(O)O2 reactions). The current work revealed, for the first time, a mechanism of RO2/RC(O)O2 reacting with α-pinene in the atmosphere, which provides new insight into the atmospheric chemistry of accretion products as SOA precursors.
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Affiliation(s)
- Xiangli Shi
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Ruoyu Tang
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Zuokang Dong
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Houfeng Liu
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Fei Xu
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Qingzhu Zhang
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Wansong Zong
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China.
| | - Jiemin Cheng
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
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12
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Mayorga R, Xia Y, Zhao Z, Long B, Zhang H. Peroxy Radical Autoxidation and Sequential Oxidation in Organic Nitrate Formation during Limonene Nighttime Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:15337-15346. [PMID: 36282674 DOI: 10.1021/acs.est.2c04030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Limonene is an abundant monoterpene released into the atmosphere via biogenic emissions and biomass burning. However, the atmospheric oxidation and secondary organic aerosol (SOA) formation mechanisms of limonene, especially during nighttime, remain largely understudied. In this work, limonene was oxidized synergistically by ozone (O3) and nitrate radicals (NO3) in a flow tube reactor and a continuous flow stirred tank reactor. Upon oxidation, many highly oxidized organic nitrates and nitrooxy peroxy radicals (RO2) were observed in the gas phase within 1 min. Combining quantum chemical calculations with kinetic simulations, we found that the primary nitrooxy RO2 (C10H16NO5) through NO3 addition at the more substituted endocyclic double bond and at the exocyclic double bond (previously considered as minor pathways) can undergo autoxidation with rate constants of around 0.02 and 20 s-1 at 298 K, respectively. These pathways could explain a major portion of the observed highly oxidized organic nitrates. In the SOA, highly oxidized mono- and dinitrates (e.g., C10H17NO7-8 and C10H16,18N2O8-10) make up a significant contribution, highlighting nitrooxy RO2 autoxidation and sequential NO3 oxidation of limonene. The same organic nitrates are also observed in ambient aerosol during biomass burning and nighttime in the southeastern United States. Therefore, the present work provides new insights into the nighttime oxidation of limonene and SOA formation in the atmosphere.
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Affiliation(s)
- Raphael Mayorga
- Department of Chemistry, University of California, Riverside, California 92507, United States
| | - Yu Xia
- School of Materials Science and Engineering, Guizhou Minzu University, Guiyang 550025, China
| | - Zixu Zhao
- Department of Chemistry, University of California, Riverside, California 92507, United States
| | - Bo Long
- School of Materials Science and Engineering, Guizhou Minzu University, Guiyang 550025, China
| | - Haofei Zhang
- Department of Chemistry, University of California, Riverside, California 92507, United States
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13
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Stratospheric Chemical Lifetime of Aviation Fuel Incomplete Combustion Products. ATMOSPHERE 2022. [DOI: 10.3390/atmos13081209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The stratosphere contains haze rich in sulfuric acid, which plays a significant role in stratospheric chemistry and in global climate. Commercial aircraft deposit significant amounts of incomplete combustion products into the lower stratosphere. We have studied the stability of these incomplete combustion products to reaction with sulfuric acid, using a predictive model based on experimental reaction kinetics. We demonstrate that sulfuric acid chemistry is likely to be a significant component of the chemistry of organics in the stratosphere. We find that at least 25 of the 40 known incomplete combustion products from aviation fuel have lifetimes to reaction with aerosol sulfuric acid of at least months. We estimate that ~109 kg of long-lived products could be deposited per year in the lower stratosphere. We suggest that the high molecular weight organic compounds formed as incomplete combustion products of commercial long-haul aviation could play a significant role in the stratosphere.
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14
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Gautam T, Wu S, Ma J, Zhao R. Potential Matrix Effects in Iodometry Determination of Peroxides Induced by Olefins. J Phys Chem A 2022; 126:2632-2644. [PMID: 35442038 DOI: 10.1021/acs.jpca.1c10717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Peroxides (H2O2, ROOR, and ROOH) are an important reaction intermediate involved in a number of natural processes, including atmospheric autoxidation and lipid peroxidation in oils and animal tissues. Iodometry is an established spectroscopic technique that has been widely used to quantify total peroxide concentration in food, indoor, and outdoor samples. Iodometry provides selectivity toward peroxides through a quantitative reaction between I- and peroxides to form I3- via a molecular iodine (I2) intermediate. However, equilibrium changes caused by a potential interaction between olefinic species and I2 can suppress I3- formation, thereby underestimating peroxide concentration. For the first time in the current study, this unrecognized interference posed by olefins (OEs) is systematically investigated to gauge its effects on the accuracy of iodometry. A number of model molecules were investigated. The interference was observed to be unique to OEs, but universally affecting different peroxide species such as H2O2, tert-butyl hydroperoxide, and aerosol-bound peroxides. A simple kinetic box model was built to explain this chemistry. The measured rate constant for 3-octenoic acid was found to be 0.84 ± 0.02 M-1 s-1. Overall, our results show matrix effects induced by OEs can underestimate peroxide concentration determined by iodometry for edible oils, indoor environments, and animal fat, but absent in most of the atmospheric samples. Nonetheless, our results point out the importance of this interfering chemistry in matrices enriched with OEs.
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Affiliation(s)
- Tania Gautam
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
| | - Shuang Wu
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
| | - Jeff Ma
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
| | - Ran Zhao
- Department of Chemistry, University of Alberta, Edmonton T6G 2G2, Alberta, Canada
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15
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Yao M, Li Z, Li C, Xiao H, Wang S, Chan AWH, Zhao Y. Isomer-Resolved Reactivity of Organic Peroxides in Monoterpene-Derived Secondary Organic Aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4882-4893. [PMID: 35357822 DOI: 10.1021/acs.est.2c01297] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Organic peroxides play a vital role in the formation, evolution, and health impacts of atmospheric aerosols, yet their molecular composition and fate in the particle phase remain poorly understood. Here, we identified, using iodometry-assisted liquid chromatography mass spectrometry, a large suite of isomer-resolved peroxide monomers (C8-10H12-18O5-8) and dimers (C15-20H22-34O5-14) in secondary organic aerosol formed from ozonolysis of the most abundant monoterpene (α-pinene). Combining aerosol isothermal evaporation experiments and multilayer kinetic modeling, bulk peroxides were found to undergo rapid particle-phase chemical transformation with an average lifetime of several hours under humid conditions, while the individual peroxides decompose on timescales of half an hour to a few days. Meanwhile, the majority of isomeric peroxides exhibit distinct particle-phase behaviors, highlighting the importance of the characterization of isomer-resolved peroxide reactivity. Furthermore, the reactivity of most peroxides increases with aerosol water content faster in a low relative humidity (RH) range than in a high RH range. Such non-uniform water effects imply a more important role of water as a plasticizer than as a reactant in influencing the peroxide reactivity. The high particle-phase reactivity of organic peroxides and its striking dependence on RH should be considered in atmospheric modeling of their fate and impacts on aerosol chemistry and health effects.
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Affiliation(s)
- Min Yao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ziyue Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chenxi Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Huayun Xiao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Shunyao Wang
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto Ontario M5S 3E5, Canada
| | - Arthur W H Chan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto Ontario M5S 3E5, Canada
| | - Yue Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
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16
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Bianco A, Neefjes I, Alfaouri D, Vehkamäki H, Kurtén T, Ahonen L, Passananti M, Kangasluoma J. Separation of isomers using a differential mobility analyser (DMA): Comparison of experimental vs modelled ion mobility. Talanta 2022; 243:123339. [DOI: 10.1016/j.talanta.2022.123339] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 02/24/2022] [Accepted: 02/26/2022] [Indexed: 01/01/2023]
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17
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Shi X, Huang G, Yang D, Zhang Q, Zong W, Cheng J, Sui X, Yuan F, Wang W. Theoretical study of the formation and nucleation mechanism of highly oxygenated multi-functional organic compounds produced by α-pinene. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 780:146422. [PMID: 33770596 DOI: 10.1016/j.scitotenv.2021.146422] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/02/2021] [Accepted: 03/08/2021] [Indexed: 06/12/2023]
Abstract
In recent years, highly oxygenated organic molecules (HOMs) derived from photochemical reactions of α-pinene, the most abundant monoterpene, have been considered as important precursors of biogenic particles. However, the specific reactions of HOMs remain largely unknown, especially the corresponding formation and nucleation mechanism in the nanoscale. In this study, we implemented quantum chemical calculations and molecular dynamics (MD) simulations to explore the mechanism of the formation of HOM monomers/dimers by ozonolysis and autoxidation of α-pinene. Furthermore, we investigated the mechanisms of HOMs with different oxygen-to‑carbon (O/C) ratios and functional groups participating in neutral and ion-induced nucleation. The results show that the formation of HOMs is hardly affected by water, sulfuric acid and ions. In the ion-induced nucleation, HOM can dominate the initial nucleation steps; however, in the neutral nucleation, HOMs are more likely to participate in the growth stage. In addition, the nucleation ability of HOM has a bearing on the O/C ratio and the types of the functional groups. The current calculations provide valuable insight into the formation mechanism of the pure organic particles at low sulfuric acid concentrations.
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Affiliation(s)
- Xiangli Shi
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Guoxuanzi Huang
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Dehui Yang
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Qingzhu Zhang
- Environment Research Institute, Shandong University, Jinan 250100, PR China
| | - Wansong Zong
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Jiemin Cheng
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China.
| | - Xiao Sui
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China
| | - Fanghui Yuan
- Rizhao Municipal Government Affairs Service Center, Rizhao 276800, PR China
| | - Wenxing Wang
- Environment Research Institute, Shandong University, Jinan 250100, PR China
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18
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Zhao Z, Zhang W, Alexander T, Zhang X, Martin DBC, Zhang H. Isolating α-Pinene Ozonolysis Pathways Reveals New Insights into Peroxy Radical Chemistry and Secondary Organic Aerosol Formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:6700-6709. [PMID: 33913707 DOI: 10.1021/acs.est.1c02107] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
α-Pinene ozonolysis is a key process that impacts the formation of new particles and secondary organic aerosol (SOA) in the atmosphere. The mechanistic understanding of this chemistry has been inconclusive despite extensive research, hindering accurate simulations of atmospheric processes. In this work, we examine the ozonolysis of two synthesized unsaturated carbonyl isomers (C11H18O) which separately produce the two Criegee intermediates (CIs) that would form simultaneously in α-pinene ozonolysis. Direct gas-phase measurements of peroxy radicals (RO2) from flowtube ozonolysis experiments by an iodide-adduct chemical ionization mass spectrometer suggest that the initial C10H15O4· RO2 from the CI with a terminal methyl ketone undergo autoxidation 20-fold faster than the CI with a terminal aldehyde and always outcompete the bimolecular reactions under typical laboratory and atmospheric conditions. These results provide experimental constraints on the detailed RO2 autoxidation mechanisms for understanding new particle formation in the atmosphere. Further, isomer-resolved characterization of the SOA formed from a continuous-flow stirred tank reactor using ion mobility spectrometry mass spectrometry suggests that the two structurally different CIs predominantly and unexpectedly form constituents with identical structures. These results open up possibilities of diverse isomerization pathways that the two CIs may undergo that form mutual products to a large extent toward their way forming the SOA. This work highlights new insights into α-pinene ozonolysis pathways and call for future studies to uncover the detailed mechanisms.
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Affiliation(s)
- Zixu Zhao
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Wen Zhang
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Taylor Alexander
- Department of Chemistry, University of California, Riverside, California 92521, United States
| | - Xuan Zhang
- Department of Life and Environmental Sciences, University of California, Merced, California 95343, United States
| | - David B C Martin
- Department of Chemistry, University of California, Riverside, California 92521, United States
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Haofei Zhang
- Department of Chemistry, University of California, Riverside, California 92521, United States
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19
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Kerecman DE, Apsokardu MJ, Talledo SL, Taylor MS, Haugh DN, Zhang Y, Johnston MV. Online Characterization of Organic Aerosol by Condensational Growth into Aqueous Droplets Coupled with Droplet-Assisted Ionization. Anal Chem 2021; 93:2793-2801. [PMID: 33513002 DOI: 10.1021/acs.analchem.0c03697] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Online analysis of ultrafine (<100 nm diameter) particles was performed by sending the aerosol through a condensation growth chamber (CGC) to create micrometer-size aqueous droplets that were subsequently analyzed by mass spectrometry with droplet-assisted ionization (DAI). Three experiments are reported which illustrate key performance characteristics of the method and give insight into the ion formation process: size-selected cortisone particles, size-selected secondary organic aerosol (SOA) particles, and freshly nucleated SOA under atmospherically relevant conditions. In each case, SOA was produced by α-pinene ozonolysis. For size-selected cortisone particles between 30 and 90 nm diameter and SOA particles between 30 and 70 nm, the ion signal intensity was found to be approximately independent of particle size. This observation is attributed to the formation of aqueous droplets in the CGC whose size distribution is independent of the original particle size. A consequence of this behavior is that the sensitivity of molecular detection increases as the particle size decreases, and the method is particularly well suited for new particle formation studies under atmospherically relevant conditions. This aspect of the CGC-DAI method was illustrated by the online analysis of freshly nucleated SOA samples with median diameters, number concentrations, and mass concentrations on the order of 25 nm, 104 cm-3, 0.2 μg m-3, respectively. Mass spectra of freshly nucleated SOA could be explained by condensation of highly oxidized molecules (HOMs) that subsequently reacted in the particle phase. Size-selected SOA showed increasing oligomerization with increasing particle size, which is consistent with established particle growth mechanisms.
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Affiliation(s)
- Devan E Kerecman
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Michael J Apsokardu
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Savannah L Talledo
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Michael S Taylor
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Devon N Haugh
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Yao Zhang
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Murray V Johnston
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
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20
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Wei J, Fang T, Wong C, Lakey PSJ, Nizkorodov SA, Shiraiwa M. Superoxide Formation from Aqueous Reactions of Biogenic Secondary Organic Aerosols. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:260-270. [PMID: 33352036 DOI: 10.1021/acs.est.0c07789] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Reactive oxygen species (ROS) play a central role in aqueous-phase processing and health effects of atmospheric aerosols. Although hydroxyl radical (•OH) and hydrogen peroxide (H2O2) are regarded as major oxidants associated with secondary organic aerosols (SOA), the kinetics and reaction mechanisms of superoxide (O2•-) formation are rarely quantified and poorly understood. Here, we demonstrate a dominant formation of O2•- with molar yields of 0.01-0.03% from aqueous reactions of biogenic SOA generated by •OH photooxidation of isoprene, β-pinene, α-terpineol, and d-limonene. The temporal evolution of •OH and O2•- formation is elucidated by kinetic modeling with a cascade of aqueous reactions including the decomposition of organic hydroperoxides, •OH oxidation of primary or secondary alcohols, and unimolecular decomposition of α-hydroxyperoxyl radicals. Relative yields of various types of ROS reflect a relative abundance of organic hydroperoxides and alcohols contained in SOA. These findings and mechanistic understanding have important implications on the atmospheric fate of SOA and particle-phase reactions of highly oxygenated organic molecules as well as oxidative stress upon respiratory deposition.
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Affiliation(s)
- Jinlai Wei
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Ting Fang
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Cynthia Wong
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Pascale S J Lakey
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Sergey A Nizkorodov
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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21
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Structural Characterisation of Dimeric Esters in α-Pinene Secondary Organic Aerosol Using N2 and CO2 Ion Mobility Mass Spectrometry. ATMOSPHERE 2020. [DOI: 10.3390/atmos12010017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The atmospheric oxidation of monoterpenes leads to the formation of secondary organic aerosol (SOA). While numerous works have been carried out in the past to characterise SOA at a molecular level, the structural elucidation of SOA compounds remains challenging owing to the lack of authentic standard compounds. In this work, the structures of α-pinene originating dimeric esters in SOA with m/z 357 (C17H25O8-) and m/z 367 (C19H27O7-) were characterised using UPLC/ESI(-)IMS-TOFMS2 (ultra-performance liquid chromatography coupled to ion mobility spectrometry tandem time-of-flight mass spectrometry). The measured collision cross-section (ΩN2) values were compared to theoretically calculated ΩN2 values. Selected product ions of dimeric compounds and the authentic standard compounds of product ions were subjected to CO2-IMS-TOFMS for more detailed structural characterisation. Our results were consistent with previously reported subunits of the m/z 357 (terpenylic acid and cis-pinic acid), and the m/z 367 (10-hydroxy-cis-pinonic acid and cis-pinic acid) ions. The measured and calculated ΩN2 values of m/z 367 ions further support the conclusion of earlier structural characterisation; however, the structure of the m/z 357 ion remains vague and requires further characterisation studies with a synthesised reference compound.
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22
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Kenseth CM, Hafeman NJ, Huang Y, Dalleska NF, Stoltz BM, Seinfeld JH. Synthesis of Carboxylic Acid and Dimer Ester Surrogates to Constrain the Abundance and Distribution of Molecular Products in α-Pinene and β-Pinene Secondary Organic Aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:12829-12839. [PMID: 32813970 DOI: 10.1021/acs.est.0c01566] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Liquid chromatography/negative electrospray ionization mass spectrometry [LC/(-)ESI-MS] is routinely employed to characterize the identity and abundance of molecular products in secondary organic aerosol (SOA) derived from monoterpene oxidation. Due to a lack of authentic standards, however, commercial terpenoic acids (e.g., cis-pinonic acid) are typically used as surrogates to quantify both monomeric and dimeric SOA constituents. Here, we synthesize a series of enantiopure, pinene-derived carboxylic acid and dimer ester homologues. We find that the (-)ESI efficiencies of the dimer esters are 19-36 times higher than that of cis-pinonic acid, demonstrating that the mass contribution of dimers to monoterpene SOA has been significantly overestimated in past studies. Using the measured (-)ESI efficiencies of the carboxylic acids and dimer esters as more representative surrogates, we determine that molecular products measureable by LC/(-)ESI-MS account for only 21.8 ± 2.6% and 18.9 ± 3.2% of the mass of SOA formed from ozonolysis of α-pinene and β-pinene, respectively. The 28-36 identified monomers (C7-10H10-18O3-6) constitute 15.6-20.5% of total SOA mass, whereas only 1.3-3.3% of the SOA mass is attributable to the 46-62 identified dimers (C15-19H24-32O4-11). The distribution of identified α-pinene and β-pinene SOA molecular products is examined as a function of carbon number (nC), average carbon oxidation state (OS¯C), and volatility (C*). The observed order-of-magnitude difference in (-)ESI efficiency between monomers and dimers is expected to be broadly applicable to other biogenic and anthropogenic SOA systems analyzed via (-) or (+) LC/ESI-MS under various LC conditions, and demonstrates that the use of unrepresentative surrogates can lead to substantial systematic errors in quantitative LC/ESI-MS analyses of SOA.
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Affiliation(s)
- Christopher M Kenseth
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Nicholas J Hafeman
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Yuanlong Huang
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, United States
| | - Nathan F Dalleska
- Environmental Analysis Center, Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, United States
| | - Brian M Stoltz
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - John H Seinfeld
- Divisions of Chemistry and Chemical Engineering and Engineering and Applied Science, California Institute of Technology, Pasadena, California 91125, United States
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23
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Sekimoto K, Fukuyama D, Inomata S. Accurate identification of dimers from α-pinene oxidation using high-resolution collision-induced dissociation mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 2020; 55:e4508. [PMID: 32145052 DOI: 10.1002/jms.4508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 02/07/2020] [Accepted: 02/23/2020] [Indexed: 06/10/2023]
Abstract
Interest in mass spectrometry of highly oxidized dimers from α-pinene oxidation has increased in the atmospheric chemistry field. Here, we apply high-resolution collision-induced dissociation mass spectrometry (HR-CID-MS) with an atmospheric pressure ionization source to investigate in detail how α-pinene-derived dimers are detected and identified by MS. The resulting HR-CID spectra and specific fragmentation patterns suggest that a large fraction of dimer ions detected in full-scan mass spectra can be hydrogen-bonded artifact clusters and the residual small fraction includes covalently bonded actual dimers. We also show how individual fractions of the artifact clusters and actual dimers are calculated using the HR-CID spectra.
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Affiliation(s)
- Kanako Sekimoto
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
- Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, 560-0043, Japan
| | - Daisuke Fukuyama
- Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, 236-0027, Japan
| | - Satoshi Inomata
- Center for Environmental Measurement and Analysis, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, 305-8506, Japan
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24
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Zhang P, Chen T, Liu J, Chu B, Ma Q, Ma J, He H. Impacts of Mixed Gaseous and Particulate Pollutants on Secondary Particle Formation during Ozonolysis of Butyl Vinyl Ether. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3909-3919. [PMID: 32108486 DOI: 10.1021/acs.est.9b07650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
To clarify how coexisting atmospheric pollutants affect secondary organic aerosol (SOA) formation, we investigated the effects of mixed gaseous pollutants (CO and SO2) and mixed organic-inorganic (MOI) particles on SOA formation during n-butyl vinyl ether (BVE) ozonolysis. Higher CO levels (90 ppm) were found to significantly change the chemical composition of SOA (prompting monomers while reducing oligomer formation) without causing much change in the overall SOA mass. Based on the positive matrix factorization (PMF) analysis, heterogeneous chemical conversions between preformed and newly formed SOA were the major pathways of SOA formation in the presence of MOI particles. Furthermore, MOI particles had an enhancing effect on SOA formation at 1% relative humidity (RH) but a negligible effect at higher RH (10 and 55%). The enhancing effect was attributed to the formation of multifunctional products resulting from high functionalization of preformed and newly formed SOA. The negligible effect observed was ascribed to the cleavage of unstable oligomers as a result of the reversible oligomerization of preformed and newly formed SOA. Even so, MOI particles could still affect the composition of newly formed SOA. These results highlight the need to account for the significant effect of mixed gaseous and particulate pollutants on both SOA constituents and their evolution.
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Affiliation(s)
- Peng Zhang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tianzeng Chen
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Liu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Biwu Chu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qingxin Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinzhu Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
- Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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25
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Qiu J, Liang Z, Tonokura K, Colussi AJ, Enami S. Stability of Monoterpene-Derived α-Hydroxyalkyl-Hydroperoxides in Aqueous Organic Media: Relevance to the Fate of Hydroperoxides in Aerosol Particle Phases. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3890-3899. [PMID: 32131591 DOI: 10.1021/acs.est.9b07497] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The α-hydroxyalkyl-hydroperoxides [R-(H)C(-OH)(-OOH), α-HH] produced in the ozonolysis of unsaturated organic compounds may contribute to secondary organic aerosol (SOA) aging. α-HHs' inherent instability, however, hampers their detection and a positive assessment of their actual role. Here we report, for the first time, the rates and products of the decomposition of the α-HHs generated in the ozonolysis of atmospherically important monoterpenes α-pinene (α-P), d-limonene (d-L), γ-terpinene (γ-Tn), and α-terpineol (α-Tp) in water/acetonitrile (W/AN) mixtures. We detect α-HHs and multifunctional decomposition products as chloride adducts by online electrospray ionization mass spectrometry. Experiments involving D2O and H218O, instead of H216O, and an OH-radical scavenger show that α-HHs decompose into gem-diols + H2O2 rather than free radicals. α-HHs decay mono- or biexponentially depending on molecular structure and solvent composition. e-Fold times, τ1/e, in water-rich solvent mixtures range from τ1/e = 15-45 min for monoterpene-derived α-HHs to τ1/e > 103 min for the α-Tp-derived α-HH. All τ1/e's dramatically increase in <20% (v/v) water. Decay rates of the α-Tp-derived α-HH in pure water increase at lower pH (2.3 ≤ pH ≤ 3.3). The hydroperoxides detected in day-old SOA samples may reflect their increased stability in water-poor media and/or the slow decomposition of α-HHs from functionalized terpenes.
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Affiliation(s)
- Junting Qiu
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Zhancong Liang
- School of Atmospheric Sciences, Sun Yat-sen University, Guangzhou, 510275, China
| | - Kenichi Tonokura
- Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8563, Japan
| | - Agustín J Colussi
- Ronald and Maxine Linde Center for Global Environmental Science, California Institute of Technology, Pasadena, California 91125, United States
| | - Shinichi Enami
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
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26
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Bagchi A, Yu Y, Huang JH, Tsai CC, Hu WP, Wang CC. Evidence and evolution of Criegee intermediates, hydroperoxides and secondary organic aerosols formedviaozonolysis of α-pinene. Phys Chem Chem Phys 2020; 22:6528-6537. [DOI: 10.1039/c9cp06306d] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first experimental evidence of Criegee intermediates formedviaα-pinene ozonolysis and the formation of secondary organic aerosols is reported using a rapid scan time-resolved FTIR spectrometer coupled with a long-path aerosol cooling chamber.
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Affiliation(s)
- Arnab Bagchi
- Department of Chemistry
- National Sun Yat-sen University
- Kaohsiung
- Republic of China
- Aerosol Science Research Center
| | - Youqing Yu
- Department of Chemistry
- National Sun Yat-sen University
- Kaohsiung
- Republic of China
| | - Jhih-Hong Huang
- Department of Chemistry
- National Sun Yat-sen University
- Kaohsiung
- Republic of China
- Aerosol Science Research Center
| | - Cheng-Cheng Tsai
- Department of Chemistry and Biochemistry
- National Chung Cheng University
- Chiayi
- Republic of China
| | - Wei-Ping Hu
- Department of Chemistry and Biochemistry
- National Chung Cheng University
- Chiayi
- Republic of China
| | - Chia C. Wang
- Department of Chemistry
- National Sun Yat-sen University
- Kaohsiung
- Republic of China
- Aerosol Science Research Center
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27
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Peng Z, Jimenez JL. Radical chemistry in oxidation flow reactors for atmospheric chemistry research. Chem Soc Rev 2020; 49:2570-2616. [DOI: 10.1039/c9cs00766k] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We summarize the studies on the chemistry in oxidation flow reactor and discuss its atmospheric relevance.
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Affiliation(s)
- Zhe Peng
- Cooperative Institute for Research in Environmental Sciences and Department of Chemistry
- University of Colorado
- Boulder
- USA
| | - Jose L. Jimenez
- Cooperative Institute for Research in Environmental Sciences and Department of Chemistry
- University of Colorado
- Boulder
- USA
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28
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Zhao Z, Tolentino R, Lee J, Vuong A, Yang X, Zhang H. Interfacial Dimerization by Organic Radical Reactions during Heterogeneous Oxidative Aging of Oxygenated Organic Aerosols. J Phys Chem A 2019; 123:10782-10792. [PMID: 31765152 DOI: 10.1021/acs.jpca.9b10779] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxidative aging of atmospheric organic aerosols (OA) substantially modifies their chemical compositions, physical properties, and hence the various environmental impacts. Here, we report observations of a previously unrecognized process leading to dimer formation during heterogeneous •OH-initiated oxidative aging of oxygenated OA. Isomer-resolved ion mobility mass spectrometry measurements and reaction-diffusion kinetic simulations are in good agreement, elucidating new mechanisms of dimerization by organic radical (i.e., peroxy and alkoxy radicals) cross reactions using glutaric acid as a surrogate oxygenated OA. These radical reactions are predicted to occur more prominently near the gas-particle interface following oxidation, especially in diffusion-limited viscous OA particles. Chemical structure analysis shows that esters dominate the detected dimers, followed by organic peroxides and ethers, highlighting the importance of acyl peroxy and acyloxy radicals. Simulations suggest that the reported dimer formation through the new interfacial mechanism could be appreciable under both laboratory and ambient conditions. Therefore, the dimers that are formed and enriched at the gas-particle interface are expected to play a crucial role in the effective reactivity, volatility, viscosity, and hygroscopicity of aged OA particles.
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Affiliation(s)
- Zixu Zhao
- Department of Chemistry , University of California at Riverside , Riverside , California 92521 , United States
| | - Ricardo Tolentino
- Department of Chemistry , University of California at Riverside , Riverside , California 92521 , United States
| | - Jennifer Lee
- Department of Chemistry , University of California at Riverside , Riverside , California 92521 , United States
| | - Austin Vuong
- Department of Molecular, Cell, and Systems Biology , University of California at Riverside , Riverside , California 92521 , United States
| | - Xiaoyan Yang
- Department of Environmental Sciences , University of California at Riverside , Riverside , California 92521 , United States
| | - Haofei Zhang
- Department of Chemistry , University of California at Riverside , Riverside , California 92521 , United States
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29
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Jaoui M, Szmigielski R, Nestorowicz K, Kolodziejczyk A, Sarang K, Rudzinski KJ, Konopka A, Bulska E, Lewandowski M, Kleindienst TE. Organic Hydroxy Acids as Highly Oxygenated Molecular (HOM) Tracers for Aged Isoprene Aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:14516-14527. [PMID: 31757124 PMCID: PMC6996142 DOI: 10.1021/acs.est.9b05075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Highly oxygenated molecules (HOMs) are a class of compounds associated with secondary organic aerosols exhibiting high oxygen to carbon (O:C) ratios and often originating from the oxidation of biogenic compounds. Here, the photooxidation and ozonolysis of isoprene were examined under a range of conditions to identify HOM tracers for aged isoprene aerosol. The HOM tracers were identified as silylated derivatives by gas chromatography-mass spectrometry and by detecting their parent compounds by liquid chromatography-high resolution mass spectrometry. In addition to the previously observed methyltetrols and 2-methylglyceric acid, seven tracer compounds were identified, including 2-methyltartronic acid (MTtA), 2-methylerythronic acid (2MeTrA), 3-methylerythronic acid (3MeTrA), 2-methylthreonic acid (2MTrA), 3-methylthreonic acid (3MTrA), erythro-methyltartaric acid (e-MTA), and threo-methyltartaric acid (t-MTA). The molecular structures were confirmed with authentic standards synthesized in the laboratory. The presence of some of these HOMs in the gas and particle phases simultaneously provides evidence of their gas/particle partitioning. To determine the contributions of aged isoprene products to ambient aerosols, we analyzed ambient PM2.5 samples collected in the southeastern United States in summer 2003 and at two European monitoring stations located in Zielonka and Godów (Poland). Our findings show that methyltartaric acids (MTA) and 2- and 3-methylthreonic acids (and their stereoisomers) are representative of aged isoprene aerosol because they occur both in the laboratory chamber aerosol obtained and in ambient PM2.5. On the basis of gas chromatography-mass spectrometry (GC-MS) analysis, their concentrations were found to range from 0.04 ng for 3-methylthreonic acid to 6.3 ng m-3 for methyltartaric acid at the southeast site in Duke Forest, NC, USA.
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Affiliation(s)
- Mohammed Jaoui
- National Exposure Research Laboratory , U.S. Environmental Protection Agency , Research Triangle Park , North Carolina 27711 , United States
| | - Rafal Szmigielski
- Environmental Chemistry Group , Institute of Physical Chemistry, Polish Academy of Sciences , 01-224 Warsaw , Poland
| | - Klara Nestorowicz
- Environmental Chemistry Group , Institute of Physical Chemistry, Polish Academy of Sciences , 01-224 Warsaw , Poland
| | - Agata Kolodziejczyk
- Environmental Chemistry Group , Institute of Physical Chemistry, Polish Academy of Sciences , 01-224 Warsaw , Poland
| | - Kumar Sarang
- Environmental Chemistry Group , Institute of Physical Chemistry, Polish Academy of Sciences , 01-224 Warsaw , Poland
| | - Krzysztof J Rudzinski
- Environmental Chemistry Group , Institute of Physical Chemistry, Polish Academy of Sciences , 01-224 Warsaw , Poland
| | - Anna Konopka
- University of Warsaw , Faculty of Chemistry, Biological and Chemical Research Centre , Żwirki i Wigury 101 , 02-089 Warsaw , Poland
| | - Ewa Bulska
- University of Warsaw , Faculty of Chemistry, Biological and Chemical Research Centre , Żwirki i Wigury 101 , 02-089 Warsaw , Poland
| | - Michael Lewandowski
- National Exposure Research Laboratory , U.S. Environmental Protection Agency , Research Triangle Park , North Carolina 27711 , United States
| | - Tadeusz E Kleindienst
- National Exposure Research Laboratory , U.S. Environmental Protection Agency , Research Triangle Park , North Carolina 27711 , United States
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30
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Tong H, Zhang Y, Filippi A, Wang T, Li C, Liu F, Leppla D, Kourtchev I, Wang K, Keskinen HM, Levula JT, Arangio AM, Shen F, Ditas F, Martin ST, Artaxo P, Godoi RHM, Yamamoto CI, de Souza RAF, Huang RJ, Berkemeier T, Wang Y, Su H, Cheng Y, Pope FD, Fu P, Yao M, Pöhlker C, Petäjä T, Kulmala M, Andreae MO, Shiraiwa M, Pöschl U, Hoffmann T, Kalberer M. Radical Formation by Fine Particulate Matter Associated with Highly Oxygenated Molecules. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:12506-12518. [PMID: 31536707 DOI: 10.1021/acs.est.9b05149] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Highly oxygenated molecules (HOMs) play an important role in the formation and evolution of secondary organic aerosols (SOA). However, the abundance of HOMs in different environments and their relation to the oxidative potential of fine particulate matter (PM) are largely unknown. Here, we investigated the relative HOM abundance and radical yield of laboratory-generated SOA and fine PM in ambient air ranging from remote forest areas to highly polluted megacities. By electron paramagnetic resonance and mass spectrometric investigations, we found that the relative abundance of HOMs, especially the dimeric and low-volatility types, in ambient fine PM was positively correlated with the formation of radicals in aqueous PM extracts. SOA from photooxidation of isoprene, ozonolysis of α- and β-pinene, and fine PM from tropical (central Amazon) and boreal (Hyytiälä, Finland) forests exhibited a higher HOM abundance and radical yield than SOA from photooxidation of naphthalene and fine PM from urban sites (Beijing, Guangzhou, Mainz, Shanghai, and Xi'an), confirming that HOMs are important constituents of biogenic SOA to generate radicals. Our study provides new insights into the chemical relationship of HOM abundance, composition, and sources with the yield of radicals by laboratory and ambient aerosols, enabling better quantification of the component-specific contribution of source- or site-specific fine PM to its climate and health effects.
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Affiliation(s)
- Haijie Tong
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Yun Zhang
- Institute of Inorganic and Analytical Chemistry , Johannes Gutenberg University , 55128 Mainz , Germany
| | - Alexander Filippi
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Ting Wang
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
- State Key Laboratory of Multiphase Flow in Power Engineering , Xi'an Jiaotong University , Xi'an 710049 , China
| | - Chenpei Li
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
- State Key Laboratory of Multiphase Flow in Power Engineering , Xi'an Jiaotong University , Xi'an 710049 , China
| | - Fobang Liu
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
- School of Chemical and Biomolecular Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Denis Leppla
- Institute of Inorganic and Analytical Chemistry , Johannes Gutenberg University , 55128 Mainz , Germany
| | - Ivan Kourtchev
- Centre for Atmospheric Science, Department of Chemistry , University of Cambridge , Cambridge CB2 1EW , United Kingdom
| | - Kai Wang
- Institute of Inorganic and Analytical Chemistry , Johannes Gutenberg University , 55128 Mainz , Germany
| | - Helmi-Marja Keskinen
- Institute for Atmospheric and Earth System Research/Physics Faculty of Science , University of Helsinki , FI-00014 Helsinki , Finland
| | - Janne T Levula
- Institute for Atmospheric and Earth System Research/Physics Faculty of Science , University of Helsinki , FI-00014 Helsinki , Finland
| | - Andrea M Arangio
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
- École polytechnique fédérale de Lausanne , Lausanne 1015 , Switzerland
| | - Fangxia Shen
- School of Space and Environment , Beihang University , Beijing 100191 , China
| | - Florian Ditas
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | | | - Paulo Artaxo
- Physics Institute , University of São Paulo , São Paulo 05508-900 , Brazil
| | - Ricardo H M Godoi
- Environmental Engineering Department , Federal University of Paraná , Curitiba , Paraná 81531-980 , Brazil
| | - Carlos I Yamamoto
- Chemical Engineering Department , Federal University of Paraná , Curitiba , Paraná 81531-970 , Brazil
| | - Rodrigo A F de Souza
- School of Technology , Amazonas State University , Manaus , Amazonas 69065-020 , Brazil
| | - Ru-Jin Huang
- Key Laboratory of Aerosol Chemistry and Physics, State Key Laboratory of Loess and Quaternary Geology , Institute of Earth and Environment, Chinese Academy of Sciences , Xi'an , 710061 , China
| | - Thomas Berkemeier
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Yueshe Wang
- State Key Laboratory of Multiphase Flow in Power Engineering , Xi'an Jiaotong University , Xi'an 710049 , China
| | - Hang Su
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Yafang Cheng
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Francis D Pope
- School of Geography, Earth and Environmental Sciences , University of Birmingham , Birmingham B15 2TT , United Kingdom
| | - Pingqing Fu
- Institute of Surface-Earth System Science , Tianjin University , Tianjin 300072 , China
| | - Maosheng Yao
- College of Environmental Sciences and Engineering , Peking University , Beijing 100871 , China
| | - Christopher Pöhlker
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Tuukka Petäjä
- Institute for Atmospheric and Earth System Research/Physics Faculty of Science , University of Helsinki , FI-00014 Helsinki , Finland
| | - Markku Kulmala
- Institute for Atmospheric and Earth System Research/Physics Faculty of Science , University of Helsinki , FI-00014 Helsinki , Finland
| | - Meinrat O Andreae
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
- Scripps Institution of Oceanography , University of California San Diego , San Diego , California 92093 , United States
| | - Manabu Shiraiwa
- Department of Chemistry , University of California , Irvine , California 92697-2025 , United States
| | - Ulrich Pöschl
- Multiphase Chemistry Department , Max Planck Institute for Chemistry , 55128 Mainz , Germany
| | - Thorsten Hoffmann
- Institute of Inorganic and Analytical Chemistry , Johannes Gutenberg University , 55128 Mainz , Germany
| | - Markus Kalberer
- Centre for Atmospheric Science, Department of Chemistry , University of Cambridge , Cambridge CB2 1EW , United Kingdom
- Department of Environmental Sciences , University of Basel , Klingelbergstrasse 27 , 4056 Basel , Switzerland
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31
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Molecular identification of organic vapors driving atmospheric nanoparticle growth. Nat Commun 2019; 10:4442. [PMID: 31570718 PMCID: PMC6769005 DOI: 10.1038/s41467-019-12473-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Accepted: 09/12/2019] [Indexed: 11/09/2022] Open
Abstract
Particles formed in the atmosphere via nucleation provide about half the number of atmospheric cloud condensation nuclei, but in many locations, this process is limited by the growth of the newly formed particles. That growth is often via condensation of organic vapors. Identification of these vapors and their sources is thus fundamental for simulating changes to aerosol-cloud interactions, which are one of the most uncertain aspects of anthropogenic climate forcing. Here we present direct molecular-level observations of a distribution of organic vapors in a forested environment that can explain simultaneously observed atmospheric nanoparticle growth from 3 to 50 nm. Furthermore, the volatility distribution of these vapors is sufficient to explain nanoparticle growth without invoking particle-phase processes. The agreement between observed mass growth, and the growth predicted from the observed mass of condensing vapors in a forested environment thus represents an important step forward in the characterization of atmospheric particle growth. Condensation of organic vapors is a main factor controlling the growth of atmospheric particles. Here the authors identify a distribution of organic vapors in a forested environment able to explain nanoparticle growth at the same location, contributing to understanding aerosol climate effects.
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32
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The role of highly oxygenated organic molecules in the Boreal aerosol-cloud-climate system. Nat Commun 2019; 10:4370. [PMID: 31554809 PMCID: PMC6761173 DOI: 10.1038/s41467-019-12338-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 09/04/2019] [Indexed: 11/21/2022] Open
Abstract
Over Boreal regions, monoterpenes emitted from the forest are the main precursors for secondary organic aerosol (SOA) formation and the primary driver of the growth of new aerosol particles to climatically important cloud condensation nuclei (CCN). Autoxidation of monoterpenes leads to rapid formation of Highly Oxygenated organic Molecules (HOM). We have developed the first model with near-explicit representation of atmospheric new particle formation (NPF) and HOM formation. The model can reproduce the observed NPF, HOM gas-phase composition and SOA formation over the Boreal forest. During the spring, HOM SOA formation increases the CCN concentration by ~10 % and causes a direct aerosol radiative forcing of −0.10 W/m2. In contrast, NPF reduces the number of CCN at updraft velocities < 0.2 m/s, and causes a direct aerosol radiative forcing of +0.15 W/m2. Hence, while HOM SOA contributes to climate cooling, NPF can result in climate warming over the Boreal forest. Forests emit compounds into the atmosphere that are oxidized into highly oxygenated molecules that serve as precursors for cloud condensation nuclei–a process that impacts the climate, but is poorly represented in models. Here the authors create a new model that accurately depicts highly oxygenated molecule and climate dynamics over Boreal forests.
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33
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Alpert PA, Corral Arroyo P, Dou J, Krieger UK, Steimer SS, Förster JD, Ditas F, Pöhlker C, Rossignol S, Passananti M, Perrier S, George C, Shiraiwa M, Berkemeier T, Watts B, Ammann M. Visualizing reaction and diffusion in xanthan gum aerosol particles exposed to ozone. Phys Chem Chem Phys 2019; 21:20613-20627. [PMID: 31528972 DOI: 10.1039/c9cp03731d] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Atmospheric aerosol particles with a high viscosity may become inhomogeneously mixed during chemical processing. Models have predicted gradients in condensed phase reactant concentration throughout particles as the result of diffusion and chemical reaction limitations, termed chemical gradients. However, these have never been directly observed for atmospherically relevant particle diameters. We investigated the reaction between ozone and aerosol particles composed of xanthan gum and FeCl2 and observed the in situ chemical reaction that oxidized Fe2+ to Fe3+ using X-ray spectromicroscopy. Iron oxidation state of particles as small as 0.2 μm in diameter were imaged over time with a spatial resolution of tens of nanometers. We found that the loss off Fe2+ accelerated with increasing ozone concentration and relative humidity, RH. Concentric 2-D column integrated profiles of the Fe2+ fraction, α, out of the total iron were derived and demonstrated that particle surfaces became oxidized while particle cores remained unreacted at RH = 0-20%. At higher RH, chemical gradients evolved over time, extended deeper from the particle surface, and Fe2+ became more homogeneously distributed. We used the kinetic multi-layer model for aerosol surface and bulk chemistry (KM-SUB) to simulate ozone reaction constrained with our observations and inferred key parameters as a function of RH including Henry's Law constant for ozone, HO3, and diffusion coefficients for ozone and iron, DO3 and DFe, respectively. We found that HO3 is higher in our xanthan gum/FeCl2 particles than for water and increases when RH decreased from about 80% to dry conditions. This coincided with a decrease in both DO3 and DFe. In order to reproduce observed chemical gradients, our model predicted that ozone could not be present further than a few nanometers from a particle surface indicating near surface reactions were driving changes in iron oxidation state. However, the observed chemical gradients in α observed over hundreds of nanometers must have been the result of iron transport from the particle interior to the surface where ozone oxidation occurred. In the context of our results, we examine the applicability of the reacto-diffusive framework and discuss diffusion limitations for other reactive gas-aerosol systems of atmospheric importance.
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Affiliation(s)
- Peter A Alpert
- Laboratory of Environmental Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.
| | - Pablo Corral Arroyo
- Laboratory of Environmental Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland. and Institute for Physical Chemistry, ETH Zürich, 8092 Zürich, Switzerland
| | - Jing Dou
- Institute for Atmospheric and Climate Science, ETH Zürich, 8092 Zürich, Switzerland
| | - Ulrich K Krieger
- Institute for Atmospheric and Climate Science, ETH Zürich, 8092 Zürich, Switzerland
| | - Sarah S Steimer
- Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Jan-David Förster
- Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Florian Ditas
- Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Christopher Pöhlker
- Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany
| | - Stéphanie Rossignol
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626, Villeurbanne, France and Aix Marseille Université, CNRS, LCE UMR 7376, 13331 Marseille, France
| | - Monica Passananti
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626, Villeurbanne, France and Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, 00710, Helsinki, Finland and Dipartimento di Chimica, Università di Torino, Via Giuria 5, 10125 Torino, Italy
| | - Sebastien Perrier
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626, Villeurbanne, France
| | - Christian George
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626, Villeurbanne, France
| | - Manabu Shiraiwa
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA
| | - Thomas Berkemeier
- Multiphase Chemistry Department, Max Planck Institute for Chemistry, 55128 Mainz, Germany and School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Benjamin Watts
- Laboratory for Synchrotron Radiation-Condensed Matter, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland
| | - Markus Ammann
- Laboratory of Environmental Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland.
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34
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Ren Y, Wang G, Tao J, Zhang Z, Wu C, Wang J, Li J, Wei J, Li H, Meng F. Seasonal characteristics of biogenic secondary organic aerosols at Mt. Wuyi in Southeastern China: Influence of anthropogenic pollutants. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 252:493-500. [PMID: 31163382 DOI: 10.1016/j.envpol.2019.05.077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 04/12/2019] [Accepted: 05/15/2019] [Indexed: 06/09/2023]
Abstract
Thirteen secondary organic aerosol (SOA) tracers of isoprene, monoterpenes and sesquiterpenes were measured for PM2.5 aerosols collected at the summit of Mt. Wuyi (1139 m, a.s.l.), to investigate their seasonality and formation mechanism. Concentrations of the isoprene and monoterpene SOA tracers were much higher in summer than those in other seasons. In contrast, β-caryophyllinic acid was found to be the lowest in summer. Concentrations of those BSOA tracers showed a positive correlation with temperature (R2 = 0.52-0.70), and a negative correlation with relative humidity (R2 = 0.43-0.78). Moreover, thermodynamic model (i.e., ISORROPIA-II) calculation results showed that acidity conditions are favorable for BSOA formation. Robust linear correlations between the BSOA tracers and anthropogenic pollutants such as SO2 (R2 = 0.53-0.7) and NO2 (R2 = 0.37-0.54) were observed for all the samples, suggesting that SO2 and NOx can enhance BSOA production in the remote mountain area of southeast China, which is related to an acid-catalyzed heterogeneous chemistry. Moreover, we also found a significant correlation between the concentrations of the BSOA tracers and levoglucosan especially for β-caryophyllinic acid, indicating that biomass burning plumes from the distant lowland regions could influence the production of BSOA in the mountain free troposphere. Our results clearly demonstrated that anthropogenic emissions in China could enhance BSOA formation in the distant mountain regions.
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Affiliation(s)
- Yanqin Ren
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Gehui Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Key Lab of Geographic Information Science of Ministry of Education of China, School of Geographic Sciences, East China Normal University, Shanghai, 200142, China.
| | - Jun Tao
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655, China
| | - Zhisheng Zhang
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou, 510655, China
| | - Can Wu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Key Lab of Geographic Information Science of Ministry of Education of China, School of Geographic Sciences, East China Normal University, Shanghai, 200142, China
| | - Jiayuan Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Jianjun Li
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China
| | - Jie Wei
- Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Hong Li
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Fan Meng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
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35
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Upshur MA, Vega MM, Bé AG, Chase HM, Zhang Y, Tuladhar A, Chase ZA, Fu L, Ebben CJ, Wang Z, Martin ST, Geiger FM, Thomson RJ. Synthesis and surface spectroscopy of α-pinene isotopologues and their corresponding secondary organic material. Chem Sci 2019; 10:8390-8398. [PMID: 31803417 PMCID: PMC6844218 DOI: 10.1039/c9sc02399b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 07/21/2019] [Indexed: 12/02/2022] Open
Abstract
The synthesis and surface-specific spectroscopic analysis of α-pinene isotopologues and their corresponding secondary organic material is reported.
Atmospheric aerosol–cloud interactions remain among the least understood processes within the climate system, leaving large uncertainties in the prediction of future climates. In particular, the nature of the surfaces of aerosol particles formed from biogenic terpenes, such as α-pinene, is poorly understood despite the importance of surface phenomena in their formation, growth, radiative properties, and ultimate fate. Herein we report the coupling of a site-specific deuterium labeling strategy with vibrational sum frequency generation (SFG) spectroscopy to probe the surface C–H oscillators in α-pinene-derived secondary organic aerosol material (SOM) generated in an atmospheric flow tube reactor. Three α-pinene isotopologues with methylene bridge, bridgehead methine, allylic, and vinyl deuteration were synthesized and their vapor phase SFG spectra were compared to that of unlabeled α-pinene. Subsequent analysis of the SFG spectra of their corresponding SOM revealed that deuteration of the bridge methylene C–H oscillators present on the cyclobutane ring in α-pinene leads to a considerable signal intensity decrease (ca. 30–40%), meriting speculation that the cyclobutane moiety remains largely intact within the surface bound species present in the SOM formed upon α-pinene oxidation. These insights provide further clues as to the complexity of aerosol particle surfaces, and establish a framework for future investigations of the heterogeneous interactions between precursor terpenes and particle surfaces that lead to aerosol particle growth under dynamically changing conditions in the atmosphere.
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Affiliation(s)
- Mary Alice Upshur
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
| | - Marvin M Vega
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
| | - Ariana Gray Bé
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
| | - Hilary M Chase
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
| | - Yue Zhang
- John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , MA 02138 , USA
| | - Aashish Tuladhar
- William R. Wiley Environmental Molecular Sciences Laboratory , Pacific Northwest National Laboratory , Richland , WA 99352 , USA
| | - Zizwe A Chase
- William R. Wiley Environmental Molecular Sciences Laboratory , Pacific Northwest National Laboratory , Richland , WA 99352 , USA
| | - Li Fu
- William R. Wiley Environmental Molecular Sciences Laboratory , Pacific Northwest National Laboratory , Richland , WA 99352 , USA
| | - Carlena J Ebben
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
| | - Zheming Wang
- William R. Wiley Environmental Molecular Sciences Laboratory , Pacific Northwest National Laboratory , Richland , WA 99352 , USA
| | - Scot T Martin
- John A. Paulson School of Engineering and Applied Sciences , Harvard University , Cambridge , MA 02138 , USA.,Department of Earth and Planetary Sciences , Harvard University , Cambridge , MA 02138 , USA
| | - Franz M Geiger
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
| | - Regan J Thomson
- Department of Chemistry , Northwestern University , Evanston , IL 60208 , USA . ;
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36
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O'Brien RE, Kroll JH. Photolytic Aging of Secondary Organic Aerosol: Evidence for a Substantial Photo-Recalcitrant Fraction. J Phys Chem Lett 2019; 10:4003-4009. [PMID: 31264874 DOI: 10.1021/acs.jpclett.9b01417] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Photolytic aging has been proposed as a major mass loss mechanism for atmospheric secondary organic aerosol (SOA). However, estimated mass loss rates vary by orders of magnitude, and their impacts on modeled SOA loadings and properties are highly uncertain. In this study, photolysis rates and composition changes of α-pinene SOA are analyzed in situ over multiple days in an environmental chamber. After an initial exponential decay (τ ∼ 22 h), the mass loss rate slows dramatically, with more than ∼70-90% of the SOA particulate mass undergoing an essentially negligible photolytic degradation. Scaled to ambient conditions, SOA undergoes rapid photolysis over only its first day in the atmosphere; beyond this, the remaining SOA is photo-recalcitrant, and photolysis ceases to be a major sink compared to wet deposition time scales. Thus, extrapolation of the initial photolysis loss rate to the entire aerosol mass may significantly overestimate the role of photolysis in the removal of atmospheric SOA.
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Affiliation(s)
- Rachel E O'Brien
- Department of Chemistry , College of William and Mary , Williamsburg , Virginia 23185 , United States
- Department of Civil and Environmental Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Jesse H Kroll
- Department of Civil and Environmental Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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37
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Johnston MV, Kerecman DE. Molecular Characterization of Atmospheric Organic Aerosol by Mass Spectrometry. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2019; 12:247-274. [PMID: 30901261 DOI: 10.1146/annurev-anchem-061516-045135] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Atmospheric aerosol, particulate matter suspended in the air we breathe, exerts a strong impact on our health and the environment. Controlling the amount of particulate matter in air is difficult, as there are many ways particles can form by both natural and anthropogenic processes. We gain insight into the sources of particulate matter through chemical composition measurements. A substantial portion of atmospheric aerosol is organic, and this organic matter is exceedingly complex on a molecular scale, encompassing hundreds to thousands of individual compounds that distribute between the gas and particle phases. Because of this complexity, no single analytical technique is sufficient. However, mass spectrometry plays a crucial role owing to its combination of high sensitivity and molecular specificity. This review surveys the various ways mass spectrometry is used to characterize atmospheric organic aerosol at a molecular level, tracing these methods from inception to current practice, with emphasis on current and emerging areas of research. Both offline and online approaches are covered, and molecular measurements with them are discussed in the context of identifying sources and elucidating the underlying chemical mechanisms of particle formation. There is an ongoing need to improve existing techniques and develop new ones if we are to further advance our knowledge of how to mitigate the unwanted health and environmental impacts of particles.
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Affiliation(s)
- Murray V Johnston
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA;
| | - Devan E Kerecman
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA;
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38
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Wang L, Liu Y, Wang L. Ozonolysis of 3-carene in the atmosphere. Formation mechanism of hydroxyl radical and secondary ozonides. Phys Chem Chem Phys 2019; 21:8081-8091. [PMID: 30932098 DOI: 10.1039/c8cp07195k] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The gas-phase ozonolysis mechanism of 3-carene is investigated using high level quantum chemistry and kinetic calculations. The reaction follows the Criegee mechanism with an initial addition of O3 to the [double bond splayed left]C[double bond, length as m-dash]C[double bond splayed right] bond, followed by a chain of unimolecular isomerizations, as 3-carene + O3→ POZs (primary ozonides) → CIs (Criegee intermediates, 4 conformers) → Ps (products). In the course of the reaction, a large excess of energy retained in the POZs* lead to the prompt unimolecular processes in POZs*, CIs*, and Ps*, and only ∼4% of CIs* could be stabilized by collision at 298 K and 760 Torr. From RRKM-ME calculations, the VHPs* could further dissociate to vinoxy-type radical and OH radical, the SOZs* could isomerize to 3-caronic acid, and DIOs* could be stabilized via collision. The fractional yield of OH radical, in the range of 0.56 to 0.59, agrees reasonably well with the previously measured value of 1.06 (with an uncertainty factor of 1.5).
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Affiliation(s)
- Lingyu Wang
- School of Chemistry & Chemical Engineering, South China University of Technology, Guangzhou, 510640, China.
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39
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Murschell T, Farmer DK. Atmospheric OH oxidation chemistry of trifluralin and acetochlor. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2019; 21:650-658. [PMID: 30805573 DOI: 10.1039/c8em00507a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Trifluralin and acetochlor are two nitrogen-containing current use herbicides. While both herbicides have been observed in the atmosphere and have the potential to undergo atmospheric oxidation before deposition to off-target areas, the atmospheric photooxidation chemistry of these species is poorly understood. We use an oxidative flow reactor to expose the two herbicides to increasing concentrations of OH radicals, detecting pesticides and products using an iodide chemical ionization mass spectrometer. We identify new oxidation products and propose photooxidation mechanisms for trifluralin and acetochlor. Both herbicides contain reduced organic nitrogen atoms, and their OH oxidation produces isocyanic acid. While aerosol was observed in the flow reactor only for acetochlor, our results indicate that OH oxidation of neither herbicide would contribute to secondary organic aerosol formation under typical ambient atmospheric conditions. However, high wall losses of both pesticides in the flow reactor suggests that partitioning to pre-existing aerosol may occur and enable subsequent transport in the atmosphere.
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Affiliation(s)
- Trey Murschell
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA.
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40
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Bianchi F, Kurtén T, Riva M, Mohr C, Rissanen MP, Roldin P, Berndt T, Crounse JD, Wennberg PO, Mentel TF, Wildt J, Junninen H, Jokinen T, Kulmala M, Worsnop DR, Thornton JA, Donahue N, Kjaergaard HG, Ehn M. Highly Oxygenated Organic Molecules (HOM) from Gas-Phase Autoxidation Involving Peroxy Radicals: A Key Contributor to Atmospheric Aerosol. Chem Rev 2019; 119:3472-3509. [PMID: 30799608 PMCID: PMC6439441 DOI: 10.1021/acs.chemrev.8b00395] [Citation(s) in RCA: 205] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
![]()
Highly
oxygenated organic molecules (HOM) are formed in the atmosphere
via autoxidation involving peroxy radicals arising from volatile organic
compounds (VOC). HOM condense on pre-existing particles and can be
involved in new particle formation. HOM thus contribute to the formation
of secondary organic aerosol (SOA), a significant and ubiquitous component
of atmospheric aerosol known to affect the Earth’s radiation
balance. HOM were discovered only very recently, but the interest
in these compounds has grown rapidly. In this Review, we define HOM
and describe the currently available techniques for their identification/quantification,
followed by a summary of the current knowledge on their formation
mechanisms and physicochemical properties. A main aim is to provide
a common frame for the currently quite fragmented literature on HOM
studies. Finally, we highlight the existing gaps in our understanding
and suggest directions for future HOM research.
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Affiliation(s)
- Federico Bianchi
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland.,Aerosol and Haze Laboratory , University of Chemical Technology , Beijing 100029 , P.R. China
| | - Theo Kurtén
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland
| | - Matthieu Riva
- IRCELYON, CNRS University of Lyon , Villeurbanne 69626 , France
| | - Claudia Mohr
- Department of Environmental Science and Analytical Chemistry , Stockholm University , Stockholm 11418 , Sweden
| | - Matti P Rissanen
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland
| | - Pontus Roldin
- Division of Nuclear Physics, Department of Physics , Lund University , Lund 22100 , Sweden
| | - Torsten Berndt
- Leibniz Institute for Tropospheric Research , Leipzig 04318 , Germany
| | - John D Crounse
- Division of Geological and Planetary Sciences , California Institute of Technology , Pasadena , California 91125 , United States
| | - Paul O Wennberg
- Division of Geological and Planetary Sciences , California Institute of Technology , Pasadena , California 91125 , United States
| | - Thomas F Mentel
- Institut für Energie und Klimaforschung, IEK-8 , Forschungszentrum Jülich GmbH , Jülich 52425 , Germany
| | - Jürgen Wildt
- Institut für Energie und Klimaforschung, IEK-8 , Forschungszentrum Jülich GmbH , Jülich 52425 , Germany
| | - Heikki Junninen
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland.,Institute of Physics , University of Tartu , Tartu 50090 , Estonia
| | - Tuija Jokinen
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland
| | - Markku Kulmala
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland.,Aerosol and Haze Laboratory , University of Chemical Technology , Beijing 100029 , P.R. China
| | - Douglas R Worsnop
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland.,Aerodyne Research Inc. , Billerica , Massachusetts 01821 , United States
| | - Joel A Thornton
- Department of Atmospheric Sciences , University of Washington , Seattle , Washington 98195 , United States
| | - Neil Donahue
- Center for Atmospheric Particle Studies , Carnegie Mellon University , Pittsburgh , Pennsylvania 15213 , United States
| | - Henrik G Kjaergaard
- Department of Chemistry , University of Cøpenhagen , Cøpenhagen 2100 , Denmark
| | - Mikael Ehn
- Institute for Atmospheric and Earth System Research, Faculty of Science , University of Helsinki , Helsinki 00014 , Finland
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41
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Praske E, Otkjær RV, Crounse JD, Hethcox JC, Stoltz BM, Kjaergaard HG, Wennberg PO. Intramolecular Hydrogen Shift Chemistry of Hydroperoxy-Substituted Peroxy Radicals. J Phys Chem A 2018; 123:590-600. [DOI: 10.1021/acs.jpca.8b09745] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eric Praske
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Rasmus V. Otkjær
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - John D. Crounse
- Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - J. Caleb Hethcox
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Brian M. Stoltz
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
| | - Henrik G. Kjaergaard
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Paul O. Wennberg
- Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
- Division of Engineering and Applied Science, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States
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42
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Berndt T, Mentler B, Scholz W, Fischer L, Herrmann H, Kulmala M, Hansel A. Accretion Product Formation from Ozonolysis and OH Radical Reaction of α-Pinene: Mechanistic Insight and the Influence of Isoprene and Ethylene. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:11069-11077. [PMID: 30192520 DOI: 10.1021/acs.est.8b02210] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
α-Pinene (C10H16) represents one of the most important biogenic emissions in the atmosphere. Its oxidation products can significantly contribute to the secondary organic aerosol (SOA) formation. Here, we report on the formation mechanism of C19 and C20 accretion products from α-pinene oxidation, which are believed to be efficient SOA precursors. Measurements have been performed in a free-jet flow system. Detection of RO2 radicals and accretion products was carried out by recent mass spectrometric techniques using different ionization schemes. Observed C10-RO2 radicals from α-pinene ozonolysis were O,O-C10H15(O2) xO2 with x = 0, 1, 2, 3 and from the OH radical reaction HO-C10H16(O2)αO2 with α = 0, 1, 2. All detected C20 accretion products can be explained via the accretion reaction RO2 + R'O2 → ROOR' + O2 starting from the measured C10-RO2 radicals. We speculate that C19 accretion products are formed in an analogous way assuming CH2O elimination. Addition of isoprene (C5H8), producing C5-RO2 radicals, leads to C15 accretion products formed via cross-reactions with C10-RO2 radicals. This process is competing with the formation of C19/C20 products from the pure α-pinene oxidation. A similar behavior has been observed for ethylene additives that form C12 accretion products. In the atmosphere, a complex accretion product spectrum from self- and cross-reactions of available RO2 radicals can be expected. Modeling atmospheric conditions revealed that C19/C20 product formation is only reduced by a factor of 1.2 or 3.6 in isoprene-dominated environments assuming a 2- or 15-fold isoprene concentration over α-pinene, respectively, as present in different forested areas.
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Affiliation(s)
- Torsten Berndt
- Atmospheric Chemistry Department (ACD) , Leibniz Institute for Tropospheric Research (TROPOS) , 04318 Leipzig , Germany
| | - Bernhard Mentler
- Institute for Ion Physics and Applied Physics , University of Innsbruck , 6020 Innsbruck , Austria
| | - Wiebke Scholz
- Institute for Ion Physics and Applied Physics , University of Innsbruck , 6020 Innsbruck , Austria
| | - Lukas Fischer
- Institute for Ion Physics and Applied Physics , University of Innsbruck , 6020 Innsbruck , Austria
| | - Hartmut Herrmann
- Atmospheric Chemistry Department (ACD) , Leibniz Institute for Tropospheric Research (TROPOS) , 04318 Leipzig , Germany
| | - Markku Kulmala
- Institute for Atmospheric and Earth System Research (INAR)/Physics , University of Helsinki , Helsinki 00014 , Finland
| | - Armin Hansel
- Institute for Ion Physics and Applied Physics , University of Innsbruck , 6020 Innsbruck , Austria
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43
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Li K, Li J, Wang W, Li J, Peng C, Wang D, Ge M. Effects of Gas-Particle Partitioning on Refractive Index and Chemical Composition of m-Xylene Secondary Organic Aerosol. J Phys Chem A 2018. [DOI: 10.1021/acs.jpca.7b12792] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kun Li
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Junling Li
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Weigang Wang
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jiangjun Li
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Chao Peng
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Dong Wang
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Maofa Ge
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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44
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Zhao R, Kenseth CM, Huang Y, Dalleska NF, Seinfeld JH. Iodometry-Assisted Liquid Chromatography Electrospray Ionization Mass Spectrometry for Analysis of Organic Peroxides: An Application to Atmospheric Secondary Organic Aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:2108-2117. [PMID: 29370527 DOI: 10.1021/acs.est.7b04863] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Organic peroxides comprise a significant fraction of atmospheric secondary organic aerosol (SOA). Detection and quantification of particle-phase organic peroxides are highly challenging, and current efforts rely significantly on filter extraction and offline mass spectrometry (MS). Here, a novel technique, iodometry-assisted liquid chromatography electrospray ionization mass spectrometry (iodometry-assisted LC-ESI-MS), is developed and evaluated with a class of atmospherically relevant organic peroxides, α-acyloxyalkyl hydroperoxides, synthesized via liquid ozonolysis. Iodometry-assisted LC-ESI-MS unambiguously distinguishes organic peroxides, compensating for the lack of functional group information that can be obtained with MS. This technique can be versatile for a wide spectrum of environmental analytical applications for which a molecular-level identification of organic peroxide is required. Here, iodometry-assisted LC-ESI-MS is applied to the water-soluble organic carbon (WSOC) of α-pinene SOA. Unexpectedly, a limited number of detectable compounds in WSOC appear to be organic peroxides, despite the fact that spectroscopy-based iodometry indicates 15% of WSOC mass is associated with organic peroxides. This observation would be consistent with decomposition of multifunctional organic peroxides to small peroxides that can be quantified by spectroscopy-based iodometry but not by LC-ESI-MS. Overall, this study raises concerns regarding filter extraction-based studies, showing that assignment of organic peroxides solely on the basis of MS signatures can be misleading.
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Affiliation(s)
- Ran Zhao
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - Christopher M Kenseth
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
| | - Yuanlong Huang
- Division of Geological and Planetary Sciences, California Institute of Technology , Pasadena, California 91125, United States
| | - Nathan F Dalleska
- Environmental Analysis Center, California Institute of Technology , Pasadena, California 91125, United States
| | - John H Seinfeld
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
- Division of Engineering and Applied Science, California Institute of Technology , Pasadena, California 91125, United States
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45
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Affiliation(s)
- Julia Laskin
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Alexander Laskin
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Sergey A Nizkorodov
- Department of Chemistry, University of California , Irvine, California 92697, United States
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46
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Praske E, Otkjær RV, Crounse JD, Hethcox JC, Stoltz BM, Kjaergaard HG, Wennberg PO. Atmospheric autoxidation is increasingly important in urban and suburban North America. Proc Natl Acad Sci U S A 2018; 115:64-69. [PMID: 29255042 PMCID: PMC5776813 DOI: 10.1073/pnas.1715540115] [Citation(s) in RCA: 110] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Gas-phase autoxidation-regenerative peroxy radical formation following intramolecular hydrogen shifts-is known to be important in the combustion of organic materials. The relevance of this chemistry in the oxidation of organics in the atmosphere has received less attention due, in part, to the lack of kinetic data at relevant temperatures. Here, we combine computational and experimental approaches to investigate the rate of autoxidation for organic peroxy radicals (RO2) produced in the oxidation of a prototypical atmospheric pollutant, n-hexane. We find that the reaction rate depends critically on the molecular configuration of the RO2 radical undergoing hydrogen transfer (H-shift). RO2 H-shift rate coefficients via transition states involving six- and seven-membered rings (1,5 and 1,6 H-shifts, respectively) of α-OH hydrogens (HOC-H) formed in this system are of order 0.1 s-1 at 296 K, while the 1,4 H-shift is calculated to be orders of magnitude slower. Consistent with H-shift reactions over a substantial energetic barrier, we find that the rate coefficients of these reactions increase rapidly with temperature and exhibit a large, primary, kinetic isotope effect. The observed H-shift rate coefficients are sufficiently fast that, as a result of ongoing NO x emission reductions, autoxidation is now competing with bimolecular chemistry even in the most polluted North American cities, particularly during summer afternoons when NO levels are low and temperatures are elevated.
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Affiliation(s)
- Eric Praske
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Rasmus V Otkjær
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - John D Crounse
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125
| | - J Caleb Hethcox
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Brian M Stoltz
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125
| | - Henrik G Kjaergaard
- Department of Chemistry, University of Copenhagen, DK-2100 Copenhagen, Denmark;
| | - Paul O Wennberg
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125;
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA 91125
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Hanson JR. The Ozonolysis of Terpenoids, a Pandora's Box of by-Products. JOURNAL OF CHEMICAL RESEARCH 2017. [DOI: 10.3184/174751917x15064232103029] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The ozonolysis of terpenoids is described and the origins of some by-products are discussed.
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Affiliation(s)
- James R. Hanson
- Department of Chemistry, University of Sussex, Brighton, Sussex BN1 9QJ, UK
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