Articles | Volume 22, issue 22
https://doi.org/10.5194/acp-22-14589-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-22-14589-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Nov 2022
Research article |
| 17 Nov 2022
| 17 Nov 2022
Atmospheric breakdown chemistry of the new “green” solvent 2,2,5,5-tetramethyloxolane via gas-phase reactions with OH and Cl radicals
Caterina Mapelli
Department of Chemistry, University of York, York, YO10 5DD, UK
Juliette V. Schleicher
Department of Chemistry, University of York, York, YO10 5DD, UK
now at: École Polytechnique Fédérale de Lausanne, 1015 Lausanne,
Switzerland
Alex Hawtin
Department of Chemistry, University of York, York, YO10 5DD, UK
Conor D. Rankine
Department of Chemistry, University of York, York, YO10 5DD, UK
Department of Chemistry, Newcastle University, Newcastle upon Tyne,
NE1 7RU, UK
Fiona C. Whiting
Department of Chemistry, University of York, York, YO10 5DD, UK
Fergal Byrne
Department of Chemistry, University of York, York, YO10 5DD, UK
Department of Chemistry, Maynooth University, Maynooth, Co. Kildare,
W23 F2H6, Ireland
C. Rob McElroy
Department of Chemistry, University of York, York, YO10 5DD, UK
Claudiu Roman
Faculty of Chemistry, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Integrated Center of Environmental Science Studies in the North
Eastern Region – CERNESIM, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Cecilia Arsene
Faculty of Chemistry, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Integrated Center of Environmental Science Studies in the North
Eastern Region – CERNESIM, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Romeo I. Olariu
Faculty of Chemistry, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Integrated Center of Environmental Science Studies in the North
Eastern Region – CERNESIM, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Iustinian G. Bejan
Faculty of Chemistry, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Integrated Center of Environmental Science Studies in the North
Eastern Region – CERNESIM, “Alexandru Ioan Cuza” University of Iasi, 11th Carol I, 700506,
Iasi, Romania
Department of Chemistry, University of York, York, YO10 5DD, UK
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James D. D'Souza Metcalf, Ruth K. Winkless, Caterina Mapelli, C. Rob McElroy, Claudiu Roman, Cecilia Arsene, Romeo I. Olariu, Iustinian G. Bejan, and Terry J. Dillon
EGUsphere, https://doi.org/10.5194/egusphere-2025-866, https://doi.org/10.5194/egusphere-2025-866, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Oxymethylene ethers are a class of sustainable compounds that could be used to replace harmful organic solvents in a range of applications. In this work we used lab-based experiments to identify the main breakdown routes of these compounds in the atmosphere. We have determined that they likely contribute less to air pollution than the compounds that they replace.
Caterina Mapelli, James K. Donnelly, Úna E. Hogan, Andrew R. Rickard, Abbie T. Robinson, Fergal Byrne, Con Rob McElroy, Basile F. E. Curchod, Daniel Hollas, and Terry J. Dillon
Atmos. Chem. Phys., 23, 7767–7779, https://doi.org/10.5194/acp-23-7767-2023, https://doi.org/10.5194/acp-23-7767-2023, 2023
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Solvents are chemical compounds with countless uses in the chemical industry, and they also represent one of the main sources of pollution in the chemical sector. Scientists are trying to develop new
greensafer solvents which present favourable advantages when compared to traditional solvents. Since the assessment of these green solvents often lacks air quality considerations, this study aims to understand the behaviour of these compounds, investigating their reactivity in the troposphere.
James D. D'Souza Metcalf, Ruth K. Winkless, Caterina Mapelli, C. Rob McElroy, Claudiu Roman, Cecilia Arsene, Romeo I. Olariu, Iustinian G. Bejan, and Terry J. Dillon
EGUsphere, https://doi.org/10.5194/egusphere-2025-866, https://doi.org/10.5194/egusphere-2025-866, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
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Oxymethylene ethers are a class of sustainable compounds that could be used to replace harmful organic solvents in a range of applications. In this work we used lab-based experiments to identify the main breakdown routes of these compounds in the atmosphere. We have determined that they likely contribute less to air pollution than the compounds that they replace.
Frank A. F. Winiberg, William J. Warman, Charlotte A. Brumby, Graham Boustead, Iustinian G. Bejan, Thomas H. Speak, Dwayne E. Heard, Daniel Stone, and Paul W. Seakins
Atmos. Meas. Tech., 16, 4375–4390, https://doi.org/10.5194/amt-16-4375-2023, https://doi.org/10.5194/amt-16-4375-2023, 2023
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OH and HO2 are key reactive intermediates in the Earth's atmosphere. Accurate measurements in either the field or simulation chambers provide a good test for chemical mechanisms. Fluorescence techniques have the appropriate sensitivity for detection but require calibration. This paper compares different methods of calibration and specifically how calibration factors vary across a temperature range relevant to atmospheric and chamber determinations.
Caterina Mapelli, James K. Donnelly, Úna E. Hogan, Andrew R. Rickard, Abbie T. Robinson, Fergal Byrne, Con Rob McElroy, Basile F. E. Curchod, Daniel Hollas, and Terry J. Dillon
Atmos. Chem. Phys., 23, 7767–7779, https://doi.org/10.5194/acp-23-7767-2023, https://doi.org/10.5194/acp-23-7767-2023, 2023
Short summary
Short summary
Solvents are chemical compounds with countless uses in the chemical industry, and they also represent one of the main sources of pollution in the chemical sector. Scientists are trying to develop new
greensafer solvents which present favourable advantages when compared to traditional solvents. Since the assessment of these green solvents often lacks air quality considerations, this study aims to understand the behaviour of these compounds, investigating their reactivity in the troposphere.
Carmen Maria Tovar, Ian Barnes, Iustinian Gabriel Bejan, and Peter Wiesen
Atmos. Chem. Phys., 22, 6989–7004, https://doi.org/10.5194/acp-22-6989-2022, https://doi.org/10.5194/acp-22-6989-2022, 2022
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This work explores the kinetics and reactivity of epoxides towards the OH radical using two different simulation chambers. Estimation of the rate coefficients has also been made using different structure–activity relationship (SAR) approaches. The results indicate a direct influence of the structural and geometric properties of the epoxides not considered in SAR estimations, influencing the reactivity of these compounds. The outcomes of this work are in very good agreement with previous studies.
Claudiu Roman, Cecilia Arsene, Iustinian Gabriel Bejan, and Romeo Iulian Olariu
Atmos. Chem. Phys., 22, 2203–2219, https://doi.org/10.5194/acp-22-2203-2022, https://doi.org/10.5194/acp-22-2203-2022, 2022
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Gas-phase reaction rate coefficients of OH radicals with four nitrocatechols have been investigated for the first time by using ESC-Q-UAIC chamber facilities. The reactivity of all investigated nitrocatechols is influenced by the formation of the intramolecular H-bonds that are connected to the deactivating electromeric effect of the NO2 group. For the 3-nitrocatechol compounds, the electromeric effect of the
freeOH group is diminished by the deactivating E-effect of the NO2 group.
Niklas Illmann, Rodrigo Gastón Gibilisco, Iustinian Gabriel Bejan, Iulia Patroescu-Klotz, and Peter Wiesen
Atmos. Chem. Phys., 21, 13667–13686, https://doi.org/10.5194/acp-21-13667-2021, https://doi.org/10.5194/acp-21-13667-2021, 2021
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Within this work we determined the rate coefficients and products of the reaction of unsaturated ketones with OH radicals in an effort to complete the gaps in the knowledge needed for modelling chemistry in the atmosphere. Both substances are potentially emitted by biomass burning, industrial activities or formed in the troposphere by oxidation of terpenes. As products we identified aldehydes and ketones which in turn are known to be responsible for the transportation of NOx species.
Jacob T. Shaw, Andrew R. Rickard, Mike J. Newland, and Terry J. Dillon
Atmos. Chem. Phys., 20, 9725–9736, https://doi.org/10.5194/acp-20-9725-2020, https://doi.org/10.5194/acp-20-9725-2020, 2020
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This work expands upon the recently developed multivariate relative rate technique, presented in Shaw et al. (2019), for the measurement of rates of reaction between aromatic and aliphatic volatile organic compounds (VOCs) and OH. Knowledge of the rates of such reactions are important for understanding air quality in urban environments. This work also provides a key validation of structure–activity relationship models, which provide a theoretical method for estimating OH + VOC kinetics.
Rodrigo Gastón Gibilisco, Ian Barnes, Iustinian Gabriel Bejan, and Peter Wiesen
Atmos. Chem. Phys., 20, 8939–8951, https://doi.org/10.5194/acp-20-8939-2020, https://doi.org/10.5194/acp-20-8939-2020, 2020
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Environmental chamber studies were performed to evaluate atmospheric degradation initiated by OH radicals for two unsaturated methoxy ketones. The main gas-phase oxidation products identified and quantified from these reactions are carbonyls and long-lived nitrogen-containing compounds such as peroxyacetyl nitrate and peroxypropionyl nitrate. The kinetic rate constants and atmospheric lifetimes were estimated, degradation mechanisms were developed, and atmospheric implications were assessed.
Terry J. Dillon and John N. Crowley
Atmos. Chem. Phys., 18, 14005–14015, https://doi.org/10.5194/acp-18-14005-2018, https://doi.org/10.5194/acp-18-14005-2018, 2018
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The reactions between electronically excited NO2* and NO3* with water vapour were studied using laser excitation of NO2 (532–647 nm) or NO3 (623–662 nm). No evidence for OH production was observed in either reaction. The reaction of NO2* with water is not a significant source of OH in the atmosphere.
Alina Giorgiana Galon-Negru, Romeo Iulian Olariu, and Cecilia Arsene
Atmos. Chem. Phys., 18, 5879–5904, https://doi.org/10.5194/acp-18-5879-2018, https://doi.org/10.5194/acp-18-5879-2018, 2018
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In north-eastern Romania, enhancement in emission sources, changes in the mixed layer depth, and specific meteorological conditions were identified as critical factors controlling the seasonal variation in particulate ionic species. Particulate NH4+ and NO3− ions were assigned as critical parameters controlling aerosol chemistry. Long-range transport phenomena play an important role. Exploring aerosols' chemical composition and chemical processes still involves many challenges.
Jacob T. Shaw, Richard T. Lidster, Danny R. Cryer, Noelia Ramirez, Fiona C. Whiting, Graham A. Boustead, Lisa K. Whalley, Trevor Ingham, Andrew R. Rickard, Rachel E. Dunmore, Dwayne E. Heard, Ally C. Lewis, Lucy J. Carpenter, Jacqui F. Hamilton, and Terry J. Dillon
Atmos. Chem. Phys., 18, 4039–4054, https://doi.org/10.5194/acp-18-4039-2018, https://doi.org/10.5194/acp-18-4039-2018, 2018
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The lifetime of a chemical in the atmosphere is largely governed by the rate of its reaction with the hydroxyl radical (OH). Measurements of rates for many of the thousands of identified volatile organic compounds (VOCs) have yet to be determined experimentally. We have developed a new technique for the rapid determination of gas-phase rate coefficients for the simultaneous reactions between multiple VOCs and OH. The method is tasted across a range of scenarios and is used to derive new values.
Katrin Dulitz, Damien Amedro, Terry J. Dillon, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 18, 2381–2394, https://doi.org/10.5194/acp-18-2381-2018, https://doi.org/10.5194/acp-18-2381-2018, 2018
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The reaction between the OH radical and HNO3 represents an important route for the release of NOx (NO and NO2) from HNO3, the most important NOx reservoir in many parts of the atmosphere. In our laboratory study, we have generated an extensive, high-quality set of rate coefficients for this reaction at different temperatures and pressures and used these to derive a new parameterisation of the rate coefficient for atmospheric modelling.
Terry J. Dillon, Katrin Dulitz, Christoph B. M. Groß, and John N. Crowley
Atmos. Chem. Phys., 17, 15137–15150, https://doi.org/10.5194/acp-17-15137-2017, https://doi.org/10.5194/acp-17-15137-2017, 2017
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A great quantity and variety of organic compounds is released to the atmosphere annually. These compounds greatly impact air chemistry, quality and climate. Laser-based experiments were used to study the atmospheric breakdown of three organics: isoprene, alpha-pinene, and delta-3-carene. Results provided important missing information for low-temperature atmospheric conditions, resolved discrepancies from previous work, and allowed estimation of lifetimes of a few hours for each compound.
Frank A. F. Winiberg, Terry J. Dillon, Stephanie C. Orr, Christoph B. M Groß, Iustinian Bejan, Charlotte A. Brumby, Matthew J. Evans, Shona C. Smith, Dwayne E. Heard, and Paul W. Seakins
Atmos. Chem. Phys., 16, 4023–4042, https://doi.org/10.5194/acp-16-4023-2016, https://doi.org/10.5194/acp-16-4023-2016, 2016
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OH radicals are important intermediates in the atmosphere, and the high concentrations observed in tropical regions are yet to be fully explained. Radical-radical reactions such as the title reaction can contribute to OH formation. This is the most fully comprehensive study of the CH3C(O)O2 + HO2 reaction with direct observation of products in all reaction channels. The implications of the new measurements on OH, PAN and NOx concentrations are considered via global models.
Related subject area
Subject: Gases | Research Activity: Laboratory Studies | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Chemical characterization of organic vapors from wood, straw, cow dung, and coal burning
Quantifying primary oxidation products in the OH-initiated reaction of benzyl alcohol
Temperature-dependent rate coefficients for the reactions of OH radicals with selected alkanes, aromatic compounds, and monoterpenes
Exploring HONO production from particulate nitrate photolysis in representative regions of China: characteristics, influencing factors, and environmental implications
Spatially separate production of hydrogen oxides and nitric oxide in lightning
Kinetics of the reactions of OH with CO, NO, NO2 and of HO2 with NO2 in air at 1 atm pressure, room temperature and tropospheric water vapour concentrations
Formation of reactive nitrogen species promoted by iron ions through the photochemistry of a neonicotinoid insecticide
Gas-phase Observations of Accretion Products from Stabilized Criegee Intermediates in Terpene Ozonolysis with Two Dicarboxylic Acids
Rate coefficients for the reactions of OH radicals with C3–C11 alkanes determined by the relative-rate technique
Formation and temperature dependence of highly oxygenated organic molecules (HOMs) from Δ3-carene ozonolysis
Mechanistic insight into the kinetic fragmentation of norpinonic acid in the gas phase: an experimental and density functional theory (DFT) study
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Impact of HO2∕RO2 ratio on highly oxygenated α-pinene photooxidation products and secondary organic aerosol formation potential
Negligible temperature dependence of the ozone–iodide reaction and implications for oceanic emissions of iodine
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On the potential use of highly oxygenated organic molecules (HOMs) as indicators for ozone formation sensitivity
Oxygenated organic molecules produced by low-NOx photooxidation of aromatic compounds: contributions to secondary organic aerosol and steric hindrance
Impact of temperature on the role of Criegee intermediates and peroxy radicals in dimer formation from β-pinene ozonolysis
Atmospheric impact of 2-methylpentanal emissions: kinetics, photochemistry, and formation of secondary pollutants
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Direct probing of acylperoxy radicals during ozonolysis of α-pinene: constraints on radical chemistry and production of highly oxygenated organic molecules
Atmospheric photooxidation and ozonolysis of sabinene: reaction rate coefficients, product yields, and chemical budget of radicals
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An aldehyde as a rapid source of secondary aerosol precursors: theoretical and experimental study of hexanal autoxidation
Measuring and modeling investigation of the net photochemical ozone production rate via an improved dual-channel reaction chamber technique
Evolution of organic carbon in the laboratory oxidation of biomass-burning emissions
Atmospheric oxidation of new “green” solvents – Part 2: methyl pivalate and pinacolone
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Selective deuteration as a tool for resolving autoxidation mechanisms in α-pinene ozonolysis
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Measurement of Henry's law and liquid-phase loss rate constants of peroxypropionic nitric anhydride (PPN) in deionized water and in n-octanol
Product distribution, kinetics, and aerosol formation from the OH oxidation of dimethyl sulfide under different RO2 regimes
Impact of cooking style and oil on semi-volatile and intermediate volatility organic compound emissions from Chinese domestic cooking
Observations of gas-phase products from the nitrate-radical-initiated oxidation of four monoterpenes
Investigation of the limonene photooxidation by OH at different NO concentrations in the atmospheric simulation chamber SAPHIR (Simulation of Atmospheric PHotochemistry In a large Reaction Chamber)
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An experimental study of the reactivity of terpinolene and β-caryophyllene with the nitrate radical
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Tiantian Wang, Jun Zhang, Houssni Lamkaddam, Kun Li, Ka Yuen Cheung, Lisa Kattner, Erlend Gammelsæter, Michael Bauer, Zachary C. J. Decker, Deepika Bhattu, Rujin Huang, Rob L. Modini, Jay G. Slowik, Imad El Haddad, Andre S. H. Prevot, and David M. Bell
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Our study analyzes real-time emissions of organic vapors from solid fuel combustion. Using the mass spectrometer, we tested various fuels, finding higher emission factors for organic vapors from wood burning. Intermediate-volatility organic compounds constituted a significant fraction of emissions in solid fuel combustion. Statistical tests identified unique potential markers. Our insights benefit air quality, climate, and health, aiding accurate emission assessments.
Reina S. Buenconsejo, Sophia M. Charan, John H. Seinfeld, and Paul O. Wennberg
Atmos. Chem. Phys., 25, 1883–1897, https://doi.org/10.5194/acp-25-1883-2025, https://doi.org/10.5194/acp-25-1883-2025, 2025
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We look at the atmospheric chemistry of a volatile chemical product (VCP), benzyl alcohol. Benzyl alcohol and other VCPs may play a significant role in the formation of urban smog. By better understanding the chemistry of VCPs like benzyl alcohol, we may better understand observed data and how VCPs affect air quality. We identify products formed from benzyl alcohol chemistry and use this chemistry to understand how benzyl alcohol forms a key component of smog, secondary organic aerosol.
Florian Berg, Anna Novelli, René Dubus, Andreas Hofzumahaus, Frank Holland, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 24, 13715–13731, https://doi.org/10.5194/acp-24-13715-2024, https://doi.org/10.5194/acp-24-13715-2024, 2024
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This study reports temperature-dependent rate coefficients of the reaction of atmospherically relevant hydrocarbons from biogenic sources (methyl vinyl ketones and monoterpenes) and anthropogenic sources (alkanes and aromatics). Measurements were done at atmospheric conditions (ambient pressure and temperature range) in air.
Bowen Li, Jian Gao, Chun Chen, Liang Wen, Yuechong Zhang, Junling Li, Yuzhe Zhang, Xiaohui Du, Kai Zhang, and Jiaqi Wang
Atmos. Chem. Phys., 24, 13183–13198, https://doi.org/10.5194/acp-24-13183-2024, https://doi.org/10.5194/acp-24-13183-2024, 2024
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The photolysis rate constant of particulate nitrate for HONO production (JNO3−–HONO), derived from PM2.5 samples collected at five representative sites in China, exhibited a wide range of variation. A parameterization equation relating JNO3−–HONO to OC/NO3− has been established and can be used to estimate JNO3−–HONO in different environments. Our work provides an important reference for research in other regions of the world where aerosol samples have a high proportion of organic components.
Jena M. Jenkins and William H. Brune
EGUsphere, https://doi.org/10.5194/egusphere-2024-3579, https://doi.org/10.5194/egusphere-2024-3579, 2024
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Both the atmosphere’s primary cleaner, the hydroxyl radical, and nitric oxide are generated in extreme amounts by lightning, and laboratory and modelling experiments demonstrate that these molecules are generated in different places in lightning flashes. Thus the hydroxyl radical is not immediately consumed by the nitric oxide and instead is available to remove other pollutants in the atmosphere. Additionally, substantial nitrous acid is also likely generated by lightning.
Michael Rolletter, Andreas Hofzumahaus, Anna Novelli, Andreas Wahner, and Hendrik Fuchs
EGUsphere, https://doi.org/10.5194/egusphere-2024-3550, https://doi.org/10.5194/egusphere-2024-3550, 2024
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Highly accurate rate coefficients of termolecular reactions between OH and HO2 radicals and reactive nitrogen oxides were measured for conditions in the lower troposphere, providing improved constraints on recommended values. No dependence on water vapour was found except for the HO2+NO2 reaction, which can be explained by an enhanced rate coefficient of the NO2 reaction with the water complex of the HO2 radical.
Zhu Ran, Yanan Hu, Yuanzhe Li, Xiaoya Gao, Can Ye, Shuai Li, Xiao Lu, Yongming Luo, Sasho Gligorovski, and Jiangping Liu
Atmos. Chem. Phys., 24, 11943–11954, https://doi.org/10.5194/acp-24-11943-2024, https://doi.org/10.5194/acp-24-11943-2024, 2024
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We report enhanced formation of nitrous acid (HONO) and NOx (NO + NO2) triggered by iron ions during photolysis of neonicotinoid insecticides at the air–water interface. This novel previously overlooked source of atmospheric HONO and NOx may be an important contribution to the global nitrogen cycle and affects atmospheric oxidizing capacity and climate change.
Yuanyuan Luo, Lauri Franzon, Jiangyi Zhang, Nina Sarnela, Neil M. Donahue, Theo Kurtén, and Mikael Ehn
EGUsphere, https://doi.org/10.5194/egusphere-2024-3323, https://doi.org/10.5194/egusphere-2024-3323, 2024
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This study explores the formation of accretion products from reactions involving highly reactive compounds, Criegee intermediates. We focused on three types of terpenes, common in nature, and their reactions with specific acids. Our findings reveal that these reactions efficiently produce expected compounds. This research enhances our understanding of how these reactions affect air quality and climate by contributing to aerosol formation, crucial for atmospheric chemistry.
Yanyan Xin, Chengtang Liu, Xiaoxiu Lun, Shuyang Xie, Junfeng Liu, and Yujing Mu
Atmos. Chem. Phys., 24, 11409–11429, https://doi.org/10.5194/acp-24-11409-2024, https://doi.org/10.5194/acp-24-11409-2024, 2024
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Rate coefficients for the reactions of OH radicals with C3–C11 alkanes were determined using the multivariate relative-rate technique. A total of 25 relative-rate coefficients at room temperature and 24 Arrhenius expressions in the temperature range of 273–323 K were obtained, which expanded the data available.
Yuanyuan Luo, Ditte Thomsen, Emil Mark Iversen, Pontus Roldin, Jane Tygesen Skønager, Linjie Li, Michael Priestley, Henrik B. Pedersen, Mattias Hallquist, Merete Bilde, Marianne Glasius, and Mikael Ehn
Atmos. Chem. Phys., 24, 9459–9473, https://doi.org/10.5194/acp-24-9459-2024, https://doi.org/10.5194/acp-24-9459-2024, 2024
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∆3-carene is abundantly emitted from vegetation, but its atmospheric oxidation chemistry has received limited attention. We explored highly oxygenated organic molecule (HOM) formation from ∆3-carene ozonolysis in chambers and investigated the impact of temperature and relative humidity on HOM formation. Our findings provide new insights into ∆3-carene oxidation pathways and their potential to impact atmospheric aerosols.
Izabela Kurzydym, Agata Błaziak, Kinga Podgórniak, Karol Kułacz, and Kacper Błaziak
Atmos. Chem. Phys., 24, 9309–9322, https://doi.org/10.5194/acp-24-9309-2024, https://doi.org/10.5194/acp-24-9309-2024, 2024
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This paper outlines a unique scientific strategy for studying the reactivity of atmospherically relevant norpinonic acid (NA). The publication offers a new toolbox, illustrating NA's fragmentation and pattern of kinetic degradation leading to the formation of new small molecules. Furthermore, the research strategy presented here demonstrates how a mass spectrometer can function as a gas-phase reactor and the quantum chemistry method can serve as a reaction model builder.
Yuwei Wang, Chuang Li, Ying Zhang, Yueyang Li, Gan Yang, Xueyan Yang, Yizhen Wu, Lei Yao, Hefeng Zhang, and Lin Wang
Atmos. Chem. Phys., 24, 7961–7981, https://doi.org/10.5194/acp-24-7961-2024, https://doi.org/10.5194/acp-24-7961-2024, 2024
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The formation and evolution mechanisms of aromatics-derived highly oxygenated organic molecules (HOMs) are essential to understand the formation of secondary organic aerosol pollution. Our conclusion highlights an underappreciated formation pathway of aromatics-derived HOMs and elucidates detailed formation mechanisms of certain HOMs, which advances our understanding of HOMs and potentially explains the existing gap between model prediction and ambient measurement of the HOMs' concentrations.
Yarê Baker, Sungah Kang, Hui Wang, Rongrong Wu, Jian Xu, Annika Zanders, Quanfu He, Thorsten Hohaus, Till Ziehm, Veronica Geretti, Thomas J. Bannan, Simon P. O'Meara, Aristeidis Voliotis, Mattias Hallquist, Gordon McFiggans, Sören R. Zorn, Andreas Wahner, and Thomas F. Mentel
Atmos. Chem. Phys., 24, 4789–4807, https://doi.org/10.5194/acp-24-4789-2024, https://doi.org/10.5194/acp-24-4789-2024, 2024
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Highly oxygenated organic molecules are important contributors to secondary organic aerosol. Their yield depends on detailed atmospheric chemical composition. One important parameter is the ratio of hydroperoxy radicals to organic peroxy radicals (HO2/RO2), and we show that higher HO2/RO2 ratios lower the secondary organic aerosol yield. This is of importance as laboratory studies are often biased towards organic peroxy radicals.
Lucy V. Brown, Ryan J. Pound, Lyndsay S. Ives, Matthew R. Jones, Stephen J. Andrews, and Lucy J. Carpenter
Atmos. Chem. Phys., 24, 3905–3923, https://doi.org/10.5194/acp-24-3905-2024, https://doi.org/10.5194/acp-24-3905-2024, 2024
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Ozone is deposited from the lower atmosphere to the surface of the ocean; however, the chemical reactions which drive this deposition are currently not well understood. Of particular importance is the reaction between ozone and iodide, and this work measures the kinetics of this reaction and its temperature dependence, which we find to be negligible. We then investigate the subsequent emissions of iodine-containing species from the surface ocean, which can further impact ozone.
Lorrie Simone Denise Jacob, Chiara Giorio, and Alexander Thomas Archibald
Atmos. Chem. Phys., 24, 3329–3347, https://doi.org/10.5194/acp-24-3329-2024, https://doi.org/10.5194/acp-24-3329-2024, 2024
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Recent studies on DMS have provided new challenges to our mechanistic understanding. Here we synthesise a number of recent studies to further develop and extend a state-of-the-art mechanism. Our new mechanism is shown to outperform all existing mechanisms when compared over a wide set of conditions. The development of an improved DMS mechanism will help lead the way to better the understanding the climate impacts of DMS emissions in past, present, and future atmospheric conditions.
Jiangyi Zhang, Jian Zhao, Yuanyuan Luo, Valter Mickwitz, Douglas Worsnop, and Mikael Ehn
Atmos. Chem. Phys., 24, 2885–2911, https://doi.org/10.5194/acp-24-2885-2024, https://doi.org/10.5194/acp-24-2885-2024, 2024
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Due to the intrinsic connection between the formation pathways of O3 and HOMs, the ratio of HOM dimers or non-nitrate monomers to HOM organic nitrates could be used to determine O3 formation regimes. Owing to the fast formation and short lifetimes of HOMs, HOM-based indicating ratios can describe O3 formation in real time. Despite the success of our approach in this simple laboratory system, applicability to the much more complex atmosphere remains to be determined.
Xi Cheng, Yong Jie Li, Yan Zheng, Keren Liao, Theodore K. Koenig, Yanli Ge, Tong Zhu, Chunxiang Ye, Xinghua Qiu, and Qi Chen
Atmos. Chem. Phys., 24, 2099–2112, https://doi.org/10.5194/acp-24-2099-2024, https://doi.org/10.5194/acp-24-2099-2024, 2024
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In this study we conducted laboratory measurements to investigate the formation of gas-phase oxygenated organic molecules (OOMs) from six aromatic volatile organic compounds (VOCs). We provide a thorough analysis on the effects of precursor structure (substituents and ring numbers) on product distribution and highlight from a laboratory perspective that heavy (e.g., double-ring) aromatic VOCs are important in initial particle growth during secondary organic aerosol formation.
Yiwei Gong, Feng Jiang, Yanxia Li, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 167–184, https://doi.org/10.5194/acp-24-167-2024, https://doi.org/10.5194/acp-24-167-2024, 2024
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This study investigates the role of the important atmospheric reactive intermediates in the formation of dimers and aerosol in monoterpene ozonolysis at different temperatures. Through conducting a series of chamber experiments and utilizing chemical kinetic and aerosol dynamic models, the SOA formation processes are better described, especially for colder regions. The results can be used to improve the chemical mechanism modeling of monoterpenes and SOA parameterization in transport models.
María Asensio, Sergio Blázquez, María Antiñolo, José Albaladejo, and Elena Jiménez
Atmos. Chem. Phys., 23, 14115–14126, https://doi.org/10.5194/acp-23-14115-2023, https://doi.org/10.5194/acp-23-14115-2023, 2023
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In this work, we focus on the atmospheric chemistry and consequences for air quality of 2-methylpentanal (2MP), which is widely used as a flavoring ingredient and as an intermediate in the synthesis of dyes, resins, and pharmaceuticals. Measurements are presented on how fast 2MP is degraded by sunlight and oxidants like hydroxyl (OH) radicals and chlorine (Cl) atoms and what products are generated. We conclude that 2MP will be degraded in a few hours, affecting local air quality.
Andrew T. Lambe, Bin Bai, Masayuki Takeuchi, Nicole Orwat, Paul M. Zimmerman, Mitchell W. Alton, Nga L. Ng, Andrew Freedman, Megan S. Claflin, Drew R. Gentner, Douglas R. Worsnop, and Pengfei Liu
Atmos. Chem. Phys., 23, 13869–13882, https://doi.org/10.5194/acp-23-13869-2023, https://doi.org/10.5194/acp-23-13869-2023, 2023
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We developed a new method to generate nitrate radicals (NO3) for atmospheric chemistry applications that works by irradiating mixtures containing ceric ammonium nitrate with a UV light at room temperature. It has several advantages over traditional NO3 sources. We characterized its performance over a range of mixture and reactor conditions as well as other irradiation products. Proof of concept was demonstrated by generating and characterizing oxidation products of the β-pinene + NO3 reaction.
Han Zang, Dandan Huang, Jiali Zhong, Ziyue Li, Chenxi Li, Huayun Xiao, and Yue Zhao
Atmos. Chem. Phys., 23, 12691–12705, https://doi.org/10.5194/acp-23-12691-2023, https://doi.org/10.5194/acp-23-12691-2023, 2023
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Acylperoxy radicals (RO2) are key intermediates in the atmospheric oxidation of organic compounds, yet our knowledge of their identities and chemistry remains poor. Using direct measurements and kinetic modeling, we identify the composition and formation pathways of acyl RO2 and quantify their contribution to highly oxygenated organic molecules during α-pinene ozonolysis, which will help to understand oxidation chemistry of monoterpenes and sources of low-volatility organics in the atmosphere.
Jacky Y. S. Pang, Florian Berg, Anna Novelli, Birger Bohn, Michelle Färber, Philip T. M. Carlsson, René Dubus, Georgios I. Gkatzelis, Franz Rohrer, Sergej Wedel, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 23, 12631–12649, https://doi.org/10.5194/acp-23-12631-2023, https://doi.org/10.5194/acp-23-12631-2023, 2023
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In this study, the oxidations of sabinene by OH radicals and ozone were investigated with an atmospheric simulation chamber. Reaction rate coefficients of the OH-oxidation reaction at temperatures between 284 to 340 K were determined for the first time in the laboratory by measuring the OH reactivity. Product yields determined in chamber experiments had good agreement with literature values, but discrepancies were found between experimental yields and expected yields from oxidation mechanisms.
Rolf Sander
Atmos. Chem. Phys., 23, 10901–12440, https://doi.org/10.5194/acp-23-10901-2023, https://doi.org/10.5194/acp-23-10901-2023, 2023
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According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution. Henry’s law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format. The compilation contains 46 434 values of Henry's law constants for 10 173 species, collected from 995 references. It is also available on the internet at https://www.henrys-law.org.
Marc von Hobe, Domenico Taraborrelli, Sascha Alber, Birger Bohn, Hans-Peter Dorn, Hendrik Fuchs, Yun Li, Chenxi Qiu, Franz Rohrer, Roberto Sommariva, Fred Stroh, Zhaofeng Tan, Sergej Wedel, and Anna Novelli
Atmos. Chem. Phys., 23, 10609–10623, https://doi.org/10.5194/acp-23-10609-2023, https://doi.org/10.5194/acp-23-10609-2023, 2023
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The trace gas carbonyl sulfide (OCS) transports sulfur from the troposphere to the stratosphere, where sulfate aerosols are formed that influence climate and stratospheric chemistry. An uncertain OCS source in the troposphere is chemical production form dimethyl sulfide (DMS), a gas released in large quantities from the oceans. We carried out experiments in a large atmospheric simulation chamber to further elucidate the chemical mechanism of OCS production from DMS.
Shawon Barua, Siddharth Iyer, Avinash Kumar, Prasenjit Seal, and Matti Rissanen
Atmos. Chem. Phys., 23, 10517–10532, https://doi.org/10.5194/acp-23-10517-2023, https://doi.org/10.5194/acp-23-10517-2023, 2023
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This work illustrates how a common volatile hydrocarbon, hexanal, has the potential to undergo atmospheric autoxidation that leads to prompt formation of condensable material that subsequently contributes to aerosol formation, deteriorating the air quality of urban atmospheres. We used the combined state-of-the-art quantum chemical modeling and experimental flow reactor experiments under atmospheric conditions to resolve the autoxidation mechanism of hexanal initiated by a common oxidant.
Yixin Hao, Jun Zhou, Jie-Ping Zhou, Yan Wang, Suxia Yang, Yibo Huangfu, Xiao-Bing Li, Chunsheng Zhang, Aiming Liu, Yanfeng Wu, Yaqing Zhou, Shuchun Yang, Yuwen Peng, Jipeng Qi, Xianjun He, Xin Song, Yubin Chen, Bin Yuan, and Min Shao
Atmos. Chem. Phys., 23, 9891–9910, https://doi.org/10.5194/acp-23-9891-2023, https://doi.org/10.5194/acp-23-9891-2023, 2023
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By employing an improved net photochemical ozone production rate (NPOPR) detection system based on the dual-channel reaction chamber technique, we measured the net photochemical ozone production rate in the Pearl River Delta in China. The photochemical ozone formation mechanisms in the reaction and reference chambers were investigated using the observation-data-constrained box model, which helped us to validate the NPOPR detection system and understand photochemical ozone formation mechanism.
Kevin J. Nihill, Matthew M. Coggon, Christopher Y. Lim, Abigail R. Koss, Bin Yuan, Jordan E. Krechmer, Kanako Sekimoto, Jose L. Jimenez, Joost de Gouw, Christopher D. Cappa, Colette L. Heald, Carsten Warneke, and Jesse H. Kroll
Atmos. Chem. Phys., 23, 7887–7899, https://doi.org/10.5194/acp-23-7887-2023, https://doi.org/10.5194/acp-23-7887-2023, 2023
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In this work, we collect emissions from controlled burns of biomass fuels that can be found in the western United States into an environmental chamber in order to simulate their oxidation as they pass through the atmosphere. These findings provide a detailed characterization of the composition of the atmosphere downwind of wildfires. In turn, this will help to explore the effects of these changing emissions on downwind populations and will also directly inform atmospheric and climate models.
Caterina Mapelli, James K. Donnelly, Úna E. Hogan, Andrew R. Rickard, Abbie T. Robinson, Fergal Byrne, Con Rob McElroy, Basile F. E. Curchod, Daniel Hollas, and Terry J. Dillon
Atmos. Chem. Phys., 23, 7767–7779, https://doi.org/10.5194/acp-23-7767-2023, https://doi.org/10.5194/acp-23-7767-2023, 2023
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Solvents are chemical compounds with countless uses in the chemical industry, and they also represent one of the main sources of pollution in the chemical sector. Scientists are trying to develop new
greensafer solvents which present favourable advantages when compared to traditional solvents. Since the assessment of these green solvents often lacks air quality considerations, this study aims to understand the behaviour of these compounds, investigating their reactivity in the troposphere.
Roland Benoit, Nesrine Belhadj, Zahraa Dbouk, Maxence Lailliau, and Philippe Dagaut
Atmos. Chem. Phys., 23, 5715–5733, https://doi.org/10.5194/acp-23-5715-2023, https://doi.org/10.5194/acp-23-5715-2023, 2023
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We observed a surprisingly similar set of oxidation product chemical formulas from limonene and α-pinene, including oligomers, formed under cool-flame (present experiments) and simulated atmospheric oxidation (literature). Data analysis indicated that a subset of chemical formulas is common to all experiments independently of experimental conditions. Also, this study indicates that many detected chemical formulas can be ascribed to an autooxidation reaction.
Melissa Meder, Otso Peräkylä, Jonathan G. Varelas, Jingyi Luo, Runlong Cai, Yanjun Zhang, Theo Kurtén, Matthieu Riva, Matti Rissanen, Franz M. Geiger, Regan J. Thomson, and Mikael Ehn
Atmos. Chem. Phys., 23, 4373–4390, https://doi.org/10.5194/acp-23-4373-2023, https://doi.org/10.5194/acp-23-4373-2023, 2023
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We discuss and show the viability of a method where multiple isotopically labelled precursors are used for probing the formation pathways of highly oxygenated organic molecules (HOMs) from the oxidation of the monoterpene a-pinene. HOMs are very important for secondary organic aerosol (SOA) formation in forested regions, and monoterpenes are the single largest source of SOA globally. The fast reactions forming HOMs have thus far remained elusive despite considerable efforts over the last decade.
Philip T. M. Carlsson, Luc Vereecken, Anna Novelli, François Bernard, Steven S. Brown, Bellamy Brownwood, Changmin Cho, John N. Crowley, Patrick Dewald, Peter M. Edwards, Nils Friedrich, Juliane L. Fry, Mattias Hallquist, Luisa Hantschke, Thorsten Hohaus, Sungah Kang, Jonathan Liebmann, Alfred W. Mayhew, Thomas Mentel, David Reimer, Franz Rohrer, Justin Shenolikar, Ralf Tillmann, Epameinondas Tsiligiannis, Rongrong Wu, Andreas Wahner, Astrid Kiendler-Scharr, and Hendrik Fuchs
Atmos. Chem. Phys., 23, 3147–3180, https://doi.org/10.5194/acp-23-3147-2023, https://doi.org/10.5194/acp-23-3147-2023, 2023
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The investigation of the night-time oxidation of the most abundant hydrocarbon, isoprene, in chamber experiments shows the importance of reaction pathways leading to epoxy products, which could enhance particle formation, that have so far not been accounted for. The chemical lifetime of organic nitrates from isoprene is long enough for the majority to be further oxidized the next day by daytime oxidants.
Kevin D. Easterbrook, Mitchell A. Vona, Kiana Nayebi-Astaneh, Amanda M. Miller, and Hans D. Osthoff
Atmos. Chem. Phys., 23, 311–322, https://doi.org/10.5194/acp-23-311-2023, https://doi.org/10.5194/acp-23-311-2023, 2023
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The trace gas peroxypropionyl nitrate (PPN) is generated in photochemical smog, phytotoxic, a strong eye irritant, and possibly mutagenic. Here, its solubility and reactivity in water and in octanol were investigated using a bubble flow apparatus, yielding its Henry's law constant and octanol–water partition coefficient (Kow). The results allow the fate of PPN to be more accurately constrained in atmospheric chemical transport models, including its uptake on clouds, organic aerosol, and leaves.
Qing Ye, Matthew B. Goss, Jordan E. Krechmer, Francesca Majluf, Alexander Zaytsev, Yaowei Li, Joseph R. Roscioli, Manjula Canagaratna, Frank N. Keutsch, Colette L. Heald, and Jesse H. Kroll
Atmos. Chem. Phys., 22, 16003–16015, https://doi.org/10.5194/acp-22-16003-2022, https://doi.org/10.5194/acp-22-16003-2022, 2022
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The atmospheric oxidation of dimethyl sulfide (DMS) is a major natural source of sulfate particles in the atmosphere. However, its mechanism is poorly constrained. In our work, laboratory measurements and mechanistic modeling were conducted to comprehensively investigate DMS oxidation products and key reaction rates. We find that the peroxy radical (RO2) has a controlling effect on product distribution and aerosol yield, with the isomerization of RO2 leading to the suppression of aerosol yield.
Kai Song, Song Guo, Yuanzheng Gong, Daqi Lv, Yuan Zhang, Zichao Wan, Tianyu Li, Wenfei Zhu, Hui Wang, Ying Yu, Rui Tan, Ruizhe Shen, Sihua Lu, Shuangde Li, Yunfa Chen, and Min Hu
Atmos. Chem. Phys., 22, 9827–9841, https://doi.org/10.5194/acp-22-9827-2022, https://doi.org/10.5194/acp-22-9827-2022, 2022
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Emissions from four typical Chinese domestic cooking and fried chicken using four kinds of oils were investigated to illustrate the impact of cooking style and oil. Of the estimated SOA, 10.2 %–32.0 % could be explained by S/IVOC oxidation. Multiway principal component analysis (MPCA) emphasizes the importance of the unsaturated fatty acid-alkadienal volatile product mechanism (oil autoxidation) accelerated by the cooking and heating procedure.
Michelia Dam, Danielle C. Draper, Andrey Marsavin, Juliane L. Fry, and James N. Smith
Atmos. Chem. Phys., 22, 9017–9031, https://doi.org/10.5194/acp-22-9017-2022, https://doi.org/10.5194/acp-22-9017-2022, 2022
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We performed chamber experiments to measure the composition of the gas-phase reaction products of nitrate-radical-initiated oxidation of four monoterpenes. The total organic yield, effective oxygen-to-carbon ratio, and dimer-to-monomer ratio were correlated with the observed particle formation for the monoterpene systems with some exceptions. The Δ-carene system produced the most particles, followed by β-pinene, with the α-pinene and α-thujene systems producing no particles.
Jacky Yat Sing Pang, Anna Novelli, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Philip T. M. Carlsson, Changmin Cho, Hans-Peter Dorn, Andreas Hofzumahaus, Xin Li, Anna Lutz, Sascha Nehr, David Reimer, Franz Rohrer, Ralf Tillmann, Robert Wegener, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 22, 8497–8527, https://doi.org/10.5194/acp-22-8497-2022, https://doi.org/10.5194/acp-22-8497-2022, 2022
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This study investigates the radical chemical budget during the limonene oxidation at different atmospheric-relevant NO concentrations in chamber experiments under atmospheric conditions. It is found that the model–measurement discrepancies of HO2 and RO2 are very large at low NO concentrations that are typical for forested environments. Possible additional processes impacting HO2 and RO2 concentrations are discussed.
Carmen Maria Tovar, Ian Barnes, Iustinian Gabriel Bejan, and Peter Wiesen
Atmos. Chem. Phys., 22, 6989–7004, https://doi.org/10.5194/acp-22-6989-2022, https://doi.org/10.5194/acp-22-6989-2022, 2022
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This work explores the kinetics and reactivity of epoxides towards the OH radical using two different simulation chambers. Estimation of the rate coefficients has also been made using different structure–activity relationship (SAR) approaches. The results indicate a direct influence of the structural and geometric properties of the epoxides not considered in SAR estimations, influencing the reactivity of these compounds. The outcomes of this work are in very good agreement with previous studies.
Axel Fouqueau, Manuela Cirtog, Mathieu Cazaunau, Edouard Pangui, Jean-François Doussin, and Bénédicte Picquet-Varrault
Atmos. Chem. Phys., 22, 6411–6434, https://doi.org/10.5194/acp-22-6411-2022, https://doi.org/10.5194/acp-22-6411-2022, 2022
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Biogenic volatile organic compounds are intensely emitted by forests and crops and react with the nitrate radical during the nighttime to form functionalized products. The purpose of this study is to furnish kinetic and mechanistic data for terpinolene and β-caryophyllene, using simulation chamber experiments. Rate constants have been measured using both relative and absolute methods, and mechanistic studies have been conducted in order to identify and quantify the main reaction products.
Yuanyuan Luo, Olga Garmash, Haiyan Li, Frans Graeffe, Arnaud P. Praplan, Anssi Liikanen, Yanjun Zhang, Melissa Meder, Otso Peräkylä, Josep Peñuelas, Ana María Yáñez-Serrano, and Mikael Ehn
Atmos. Chem. Phys., 22, 5619–5637, https://doi.org/10.5194/acp-22-5619-2022, https://doi.org/10.5194/acp-22-5619-2022, 2022
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Diterpenes were only recently observed in the atmosphere, and little is known of their atmospheric fates. We explored the ozonolysis of the diterpene kaurene in a chamber, and we characterized the oxidation products for the first time using chemical ionization mass spectrometry. Our findings highlight similarities and differences between diterpenes and smaller terpenes during their atmospheric oxidation.
Wenyu Sun, Matias Berasategui, Andrea Pozzer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 22, 4969–4984, https://doi.org/10.5194/acp-22-4969-2022, https://doi.org/10.5194/acp-22-4969-2022, 2022
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The reaction between OH and SO2 is a termolecular process that in the atmosphere results in the formation of H2SO4 and thus aerosols. We present the first temperature- and pressure-dependent measurements of the rate coefficients in N2. This is also the first study to examine the effects of water vapour on the kinetics of this reaction. Our results indicate the rate coefficient is larger than that recommended by evaluation panels, with deviations of up to 30 % in some parts of the atmosphere.
Haoyu Jiang, Yingyao He, Yiqun Wang, Sheng Li, Bin Jiang, Luca Carena, Xue Li, Lihua Yang, Tiangang Luan, Davide Vione, and Sasho Gligorovski
Atmos. Chem. Phys., 22, 4237–4252, https://doi.org/10.5194/acp-22-4237-2022, https://doi.org/10.5194/acp-22-4237-2022, 2022
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Heterogeneous oxidation of SO2 is suggested to be one of the most important pathways for sulfate formation during extreme haze events in China, yet the exact mechanism remains highly uncertain. Our study reveals that ubiquitous compounds at the sea surface PAHS and DMSO, when exposed to SO2 under simulated sunlight irradiation, generate abundant organic sulfur compounds, providing implications for air-sea interaction and secondary organic aerosols formation processes.
Roland Vernooij, Ulrike Dusek, Maria Elena Popa, Peng Yao, Anupam Shaikat, Chenxi Qiu, Patrik Winiger, Carina van der Veen, Thomas Callum Eames, Natasha Ribeiro, and Guido R. van der Werf
Atmos. Chem. Phys., 22, 2871–2890, https://doi.org/10.5194/acp-22-2871-2022, https://doi.org/10.5194/acp-22-2871-2022, 2022
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Landscape fires are a major source of greenhouse gases and aerosols, particularly in sub-tropical savannas. Stable carbon isotopes in emissions can be used to trace the contribution of C3 plants (e.g. trees or shrubs) and C4 plants (e.g. savanna grasses) to greenhouse gases and aerosols if the process is well understood. This helps us to link individual vegetation types to emissions, identify biomass burning emissions in the atmosphere, and improve the reconstruction of historic fire regimes.
María Asensio, María Antiñolo, Sergio Blázquez, José Albaladejo, and Elena Jiménez
Atmos. Chem. Phys., 22, 2689–2701, https://doi.org/10.5194/acp-22-2689-2022, https://doi.org/10.5194/acp-22-2689-2022, 2022
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The diurnal atmospheric degradation of 2-methylbutanal, 2 MB, emitted by sources like vegetation or the poultry industry is evaluated in this work. Sunlight and oxidants like hydroxyl (OH) radicals and chlorine (Cl) atoms initiate this degradation. Measurements of how fast 2 MB is degraded and what products are generated are presented. The lifetime of 2 MB is around 1 h at noon, when the OH reaction dominates. Thus, 2 MB will not be transported far, affecting only local air quality.
Claudiu Roman, Cecilia Arsene, Iustinian Gabriel Bejan, and Romeo Iulian Olariu
Atmos. Chem. Phys., 22, 2203–2219, https://doi.org/10.5194/acp-22-2203-2022, https://doi.org/10.5194/acp-22-2203-2022, 2022
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Gas-phase reaction rate coefficients of OH radicals with four nitrocatechols have been investigated for the first time by using ESC-Q-UAIC chamber facilities. The reactivity of all investigated nitrocatechols is influenced by the formation of the intramolecular H-bonds that are connected to the deactivating electromeric effect of the NO2 group. For the 3-nitrocatechol compounds, the electromeric effect of the
freeOH group is diminished by the deactivating E-effect of the NO2 group.
Zhiyuan Gao, Nicolas-Xavier Geilfus, Alfonso Saiz-Lopez, and Feiyue Wang
Atmos. Chem. Phys., 22, 1811–1824, https://doi.org/10.5194/acp-22-1811-2022, https://doi.org/10.5194/acp-22-1811-2022, 2022
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Every spring in the Arctic, a series of photochemical events occur over the ice-covered ocean, known as bromine explosion events, ozone depletion events, and mercury depletion events. Here we report the re-creation of these events at an outdoor sea ice facility in Winnipeg, Canada, far away from the Arctic. The success provides a new platform with new opportunities to uncover fundamental mechanisms of these Arctic springtime phenomena and how they may change in a changing climate.
Haichao Wang, Chao Peng, Xuan Wang, Shengrong Lou, Keding Lu, Guicheng Gan, Xiaohong Jia, Xiaorui Chen, Jun Chen, Hongli Wang, Shaojia Fan, Xinming Wang, and Mingjin Tang
Atmos. Chem. Phys., 22, 1845–1859, https://doi.org/10.5194/acp-22-1845-2022, https://doi.org/10.5194/acp-22-1845-2022, 2022
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Via combining laboratory and modeling work, we found that heterogeneous reaction of N2O5 with saline mineral dust aerosol could be an important source of tropospheric ClNO2 in inland regions.
Mike J. Newland, Yangang Ren, Max R. McGillen, Lisa Michelat, Véronique Daële, and Abdelwahid Mellouki
Atmos. Chem. Phys., 22, 1761–1772, https://doi.org/10.5194/acp-22-1761-2022, https://doi.org/10.5194/acp-22-1761-2022, 2022
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Wildfires are increasing in extent and severity, driven by climate change. Such fires emit large amounts of volatile organic compounds (VOCs) to the atmosphere. Many of these, such as the furans studied here, are very reactive and are rapidly converted to other VOCs, which are expected to have negative health effects and to further impact the climate. Here, we establish the importance of the nitrate radical for removing these compounds both during the night and during the day.
Delaney B. Kilgour, Gordon A. Novak, Jon S. Sauer, Alexia N. Moore, Julie Dinasquet, Sarah Amiri, Emily B. Franklin, Kathryn Mayer, Margaux Winter, Clare K. Morris, Tyler Price, Francesca Malfatti, Daniel R. Crocker, Christopher Lee, Christopher D. Cappa, Allen H. Goldstein, Kimberly A. Prather, and Timothy H. Bertram
Atmos. Chem. Phys., 22, 1601–1613, https://doi.org/10.5194/acp-22-1601-2022, https://doi.org/10.5194/acp-22-1601-2022, 2022
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We report measurements of gas-phase volatile organosulfur molecules made during a mesocosm phytoplankton bloom experiment. Dimethyl sulfide (DMS), methanethiol (MeSH), and benzothiazole accounted for on average over 90 % of total gas-phase sulfur emissions. This work focuses on factors controlling the production and emission of DMS and MeSH and the role of non-DMS molecules (such as MeSH and benzothiazole) in secondary sulfate formation in coastal marine environments.
Niklas Illmann, Iulia Patroescu-Klotz, and Peter Wiesen
Atmos. Chem. Phys., 21, 18557–18572, https://doi.org/10.5194/acp-21-18557-2021, https://doi.org/10.5194/acp-21-18557-2021, 2021
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Understanding the chemistry of biomass burning plumes is of global interest. Within this work we investigated the OH radical reaction of 3-penten-2-one, which has been identified in biomass burning emissions. We observed the primary formation of peroxyacetyl nitrate (PAN), a key NOx reservoir species. Besides, PAN precursors were also identified as main oxidation products. 3-Penten-2-one is shown to be an example explaining rapid PAN formation within young biomass burning plumes.
Zhaofeng Tan, Luisa Hantschke, Martin Kaminski, Ismail-Hakki Acir, Birger Bohn, Changmin Cho, Hans-Peter Dorn, Xin Li, Anna Novelli, Sascha Nehr, Franz Rohrer, Ralf Tillmann, Robert Wegener, Andreas Hofzumahaus, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Chem. Phys., 21, 16067–16091, https://doi.org/10.5194/acp-21-16067-2021, https://doi.org/10.5194/acp-21-16067-2021, 2021
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The photo-oxidation of myrcene, a monoterpene species emitted by plants, was investigated at atmospheric conditions in the outdoor simulation chamber SAPHIR. The chemical structure of myrcene is partly similar to isoprene. Therefore, it can be expected that hydrogen shift reactions could play a role as observed for isoprene. In this work, their potential impact on the regeneration efficiency of hydroxyl radicals is investigated.
Cited articles
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Short summary
Solvents represent an important source of pollution from the chemical industry. New "green" solvents aim to replace toxic solvents with new molecules made from renewable sources and designed to be less harmful. Whilst these new molecules are selected according to toxicity and other characteristics, no consideration has yet been included on air quality. Studying the solvent breakdown in air, we found that TMO has a lower impact on air quality than traditional solvents with similar properties.
Solvents represent an important source of pollution from the chemical industry. New "green"...
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