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1. Low-volatility compounds contribute significantly to isoprene secondary organic aerosol (SOA) under high-NOx conditions

Author

Yuanlong Huang, Weimeng Kong, Richard C. Flagan, John H. Seinfeld, Rebecca H. Schwantes, Tran B. Nguyen, Kelvin H. Bates, Sophia M. Charan, and Huajun Mai

Subjects
Glyceric acid, Reaction conditions, Atmospheric Science, 010504 meteorology & atmospheric sciences, 010501 environmental sciences, Inorganic ions, Photochemistry, behavioral disciplines and activities, 01 natural sciences, Aerosol, chemistry.chemical_compound, chemistry, 13. Climate action, Global modeling, Volatility (chemistry), NOx, Isoprene, 0105 earth and related environmental sciences
Abstract

Recent advances in our knowledge of the gas-phase oxidation of isoprene, the impact of chamber walls on secondary organic aerosol (SOA) mass yields, and aerosol measurement analysis techniques warrant reevaluating SOA yields from isoprene. In particular, SOA from isoprene oxidation under high-NOx conditions forms via two major pathways: (1) low-volatility nitrates and dinitrates (LV pathway) and (2) hydroxymethyl-methyl-α-lactone (HMML) reaction on a surface or the condensed phase of particles to form 2-methyl glyceric acid and its oligomers (2MGA pathway). These SOA production pathways respond differently to reaction conditions. Past chamber experiments generated SOA with varying contributions from these two unique pathways, leading to results that are difficult to interpret. This study examines the SOA yields from these two pathways independently, which improves the interpretation of previous results and provides further understanding of the relevance of chamber SOA yields to the atmosphere and regional or global modeling. Results suggest that low-volatility nitrates and dinitrates produce significantly more aerosol than previously thought; the experimentally measured SOA mass yield from the LV pathway is ∼0.15. Sufficient seed surface area at the start of the reaction is needed to limit the effects of vapor wall losses of low-volatility compounds and accurately measure the complete SOA mass yield. Under dry conditions, substantial amounts of SOA are formed from HMML ring-opening reactions with inorganic ions and HMML organic oligomerization processes. However, the lactone organic oligomerization reactions are suppressed under more atmospherically relevant humidity levels, where hydration of the lactone is more competitive. This limits the SOA formation potential from the 2MGA pathway to HMML ring-opening reactions with water or inorganic ions under typical atmospheric conditions. The isoprene SOA mass yield from the LV pathway measured in this work is significantly higher than previous studies have reported, suggesting that low-volatility compounds such as organic nitrates and dinitrates may contribute to isoprene SOA under high-NOx conditions significantly more than previously thought and thus deserve continued study.

Published
2019
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3. Supplementary material to 'The driving factors of new particle formation and growth in the polluted boundary layer'

Author

Mao Xiao, Christopher R. Hoyle, Lubna Dada, Dominik Stolzenburg, Andreas Kürten, Mingyi Wang, Houssni Lamkaddam, Olga Garmash, Bernhard Mentler, Ugo Molteni, Andrea Baccarini, Mario Simon, Xu-Cheng He, Katrianne Lehtipalo, Lauri R. Ahonen, Rima Baalbaki, Paulus S. Bauer, Lisa Beck, David Bell, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, António Dias, Jonathan Duplissy, Henning Finkenzeller, Hamish Gordon, Victoria Hofbauer, Changhyuk Kim, Theodore K. Koenig, Janne Lampilahti, Chuan Ping Lee, Zijun Li, Huajun Mai, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Serge Mathot, Roy L. Mauldin, Wei Nie, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane L. J. Quéléver, Matti Rissanen, Siegfried Schobesberger, Simone Schuchmann, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Robert Wanger, Yonghong Wang, Lena Weitz, Daniela Wimmer, Yusheng Wu, Chao Yan, Penglin Ye, Qing Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Ken Carslaw, Joachim Curtius, Armin Hansel, Rainer Volkamer, Paul M. Winkler, Richard C. Flagan, Markku Kulmala, Douglas R. Worsnop, Jasper Kirkby, Neil M. Donahue, Urs Baltensperger, Imad El Haddad, and Josef Dommen

Published
2021
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4. Supplementary material to 'Molecular understanding of the suppression of new-particle formation by isoprene'

Author

Martin Heinritzi, Lubna Dada, Mario Simon, Dominik Stolzenburg, Andrea C. Wagner, Lukas Fischer, Lauri R. Ahonen, Stavros Amanatidis, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Bernhard Baumgartner, Federico Bianchi, Sophia Brilke, Dexian Chen, Randall Chiu, Antonio Dias, Josef Dommen, Jonathan Duplissy, Henning Finkenzeller, Carla Frege, Claudia Fuchs, Olga Garmash, Hamish Gordon, Manuel Granzin, Imad El Haddad, Xucheng He, Johanna Helm, Victoria Hofbauer, Christopher R. Hoyle, Juha Kangasluoma, Timo Keber, Changhyuk Kim, Andreas Kürten, Houssni Lamkaddam, Janne Lampilahti, Tiia M. Laurila, Chuan Ping Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Vladimir Makhmutov, Hanna Elina Manninen, Ruby Marten, Serge Mathot, Roy Lee Mauldin, Bernhard Mentler, Ugo Molteni, Tatjana Müller, Wei Nie, Tuomo Nieminen, Antti Onnela, Eva Partoll, Monica Passananti, Tuukka Petäjä, Joschka Pfeifer, Veronika Pospisilova, Lauriane Quéléver, Matti P. Rissanen, Clémence Rose, Siegfried Schobesberger, Wiebke Scholz, Kay Scholze, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, Miguel Vazquez-Pufleau, Annele Virtanen, Alexander L. Vogel, Rainer Volkamer, Robert Wagner, Mingyi Wang, Lena Weitz, Daniela Wimmer, Mao Xiao, Chao Yan, Penglin Ye, Qiaozhi Zha, Xueqin Zhou, Antonio Amorim, Urs Baltensperger, Armin Hansel, Markku Kulmala, António Tomé, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius

Published
2020
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5. Molecular understanding of new-particle formation from alpha-pinene between −50 °C and 25 °C

Author

Mario Simon, Lubna Dada, Martin Heinritzi, Wiebke Scholz, Dominik Stolzenburg, Lukas Fischer, Andrea C. Wagner, Andreas Kürten, Birte Rörup, Xu-Cheng He, João Almeida, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Lisa Beck, Anton Bergen, Federico Bianchi, Steffen Bräkling, Sophia Brilke, Lucia Caudillo, Dexian Chen, Biwu Chu, António Dias, Danielle C. Draper, Jonathan Duplissy, Imad El Haddad, Henning Finkenzeller, Carla Frege, Loic Gonzalez-Carracedo, Hamish Gordon, Manuel Granzin, Jani Hakala, Victoria Hofbauer, Christopher R. Hoyle, Changhyuk Kim, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Bernhard Mentler, Ugo Molteni, Leonid Nichman, Wei Nie, Andrea Ojdanic, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Lauriane L. J. Quéléver, Ananth Ranjithkumar, Matti Rissanen, Simon Schallhart, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee J. Tham, António R. Tomé, Miguel Vazquez-Pufleau, Alexander Vogel, Robert Wagner, Mingyi Wang, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, Yusheng Wu, Mao Xiao, Chao Yan, Penglin Ye, Qing Ye, Marcel Zauner-Wieczorek, Xueqin Zhou, Urs Baltensperger, Josef Dommen, Rick C. Flagan, Armin Hansel, Markku Kulmala, Rainer Volkamer, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius

Subjects
0301 basic medicine, 03 medical and health sciences, 030104 developmental biology, 13. Climate action
Abstract

Highly-oxygenated organic molecules (HOMs) contribute substantially to the formation and growth of atmospheric aerosol particles, which affect air quality, human health and Earth's climate. HOMs are formed by rapid, gas-phase autoxidation of volatile organic compounds (VOCs) such as α-pinene, the most abundant monoterpene in the atmosphere. Due to their abundance and low volatility, HOMs can play an important role for new-particle formation (NPF) and the early growth of atmospheric aerosols, even without any further assistance of other low-volatility compounds such as sulfuric acid. Both the autoxidation reaction forming HOMs and their new-particle formation rates are expected to be strongly dependent on temperature. However, experimental data on both effects are limited. Dedicated experiments were performed at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN to address this question. In this study, we show that a decrease in temperature (from +25 to −50 °C) results in a reduced HOM yield and reduced oxidation state of the products, whereas the new-particle formation rates (J1.7 nm) increase substantially. Measurements with two different chemical ionization mass spectrometers (using nitrate and protonated water as reagent ion, respectively) provide the molecular composition of the gaseous oxidation products and a 2-dimensional volatility basis set model (2D-VBS) provides their volatility distribution. The HOM yield decreases with temperature from 6.2 % at 25 °C to 0.7 % at −50 °C. However, there is a strong reduction of the saturation vapor pressure of each oxidation state as the temperature is reduced. Overall, the reduction in volatility with temperature leads to an increase in the nucleation rates by up to three orders of magnitude at −50 °C compared with 25 °C. In addition, the enhancement of the nucleation rates by ions decreases with decreasing temperature, since the neutral molecular clusters have increased stability against evaporation. The resulting data quantify how the interplay between the temperature-dependent oxidation pathways and the associated vapor pressures affect biogenic new-particle formation at the molecular level. Our measurements therefore improve our understanding of pure biogenic new-particle formation for a wide range of tropospheric temperatures and precursor concentrations.

Published
2020
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6. Supplementary material to 'Molecular understanding of new-particle formation from alpha-pinene between −50 °C and 25 °C'

Author

Mario Simon, Lubna Dada, Martin Heinritzi, Wiebke Scholz, Dominik Stolzenburg, Lukas Fischer, Andrea C. Wagner, Andreas Kürten, Birte Rörup, Xu-Cheng He, João Almeida, Rima Baalbaki, Andrea Baccarini, Paulus S. Bauer, Lisa Beck, Anton Bergen, Federico Bianchi, Steffen Bräkling, Sophia Brilke, Lucia Caudillo, Dexian Chen, Biwu Chu, António Dias, Danielle C. Draper, Jonathan Duplissy, Imad El Haddad, Henning Finkenzeller, Carla Frege, Loic Gonzalez-Carracedo, Hamish Gordon, Manuel Granzin, Jani Hakala, Victoria Hofbauer, Christopher R. Hoyle, Changhyuk Kim, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Katrianne Lehtipalo, Markus Leiminger, Huajun Mai, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Bernhard Mentler, Ugo Molteni, Leonid Nichman, Wei Nie, Andrea Ojdanic, Antti Onnela, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Lauriane L. J. Quéléver, Ananth Ranjithkumar, Matti Rissanen, Simon Schallhart, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee J. Tham, António R. Tomé, Miguel Vazquez-Pufleau, Alexander Vogel, Robert Wagner, Mingyi Wang, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, Yusheng Wu, Mao Xiao, Chao Yan, Penglin Ye, Qing Ye, Marcel Zauner-Wieczorek, Xueqin Zhou, Urs Baltensperger, Josef Dommen, Rick C. Flagan, Armin Hansel, Markku Kulmala, Rainer Volkamer, Paul M. Winkler, Douglas R. Worsnop, Neil M. Donahue, Jasper Kirkby, and Joachim Curtius

Published
2020
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7. Size-dependent influence of NO x on the growth rates of organic aerosol particles

Author

Antonio Dias, Martin Breitenlechner, Urs Baltensperger, Dominik Stolzenburg, Juha Kangasluoma, Felix Piel, Roberto Guida, Richard C. Flagan, Lubna Dada, Sophia Brilke, Jasmin Tröstl, Neil M. Donahue, Claudia Heyn, Matti P. Rissanen, Serge Mathot, Pontus Roldin, Roy L. Mauldin, Mario Simon, J. Dommen, Paul M. Winkler, Huajun Mai, Andreas Kürten, António Tomé, Hamish Gordon, Chao Yan, Kamalika Sengupta, Manjula R. Canagaratna, Joachim Curtius, Olga Garmash, Clémence Rose, Ilona Riipinen, Tuija Jokinen, Angela Buchholz, Aki Pajunoja, Lauri Ahonen, Danielle C. Draper, Kenneth S. Carslaw, Victoria Hofbauer, Michael J. Lawler, Arttu Ylisirniö, Xuemeng Chen, Nina Sarnela, Antti Onnela, Anne-Kathrin Bernhammer, António Amorim, Lukas Fischer, Qiaozhi Zha, Jasper Kirkby, Carla Frege, Martin Heinritzi, Lauriane L. J. Quéléver, Paulus Salomon Bauer, James N. Smith, Jani Hakala, V.-M. Kerminen, Mao Xiao, Liine Heikkinen, Olli Väisänen, Leonid Nichman, Mikko Sipilä, Douglas R. Worsnop, Tuukka Petäjä, Tuomo Nieminen, Annele Virtanen, Andrea Christine Wagner, Andrea Ojdanic, Aijun Ding, Anton Bergen, Katrianne Lehtipalo, Christopher R. Hoyle, F. Bianchi, Markku Kulmala, Simon Schallhart, Jonathan Duplissy, Penglin Ye, Mikael Ehn, Jenni Kontkanen, Alexander L. Vogel, S. Buenrostro Mazon, Robert Wagner, John B. Nowak, Ugo Molteni, Wei Nie, Armin Hansel, Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Nanjing University (NJU), CERN [Genève], Institute for Atmospheric and Environmental Sciences [Frankfurt/Main] (IAU), Goethe-University Frankfurt am Main, Laboratory of Atmospheric Chemistry [Paul Scherrer Institute] (LAC), Paul Scherrer Institute (PSI), Finnish Meteorological Institute (FMI), University of Vienna [Vienna], Institut für Ionenphysik und Angewandte Physik - Institute for Ion Physics and Applied Physics [Innsbruck], Leopold Franzens Universität Innsbruck - University of Innsbruck, Laboratoire de météorologie physique (LaMP), Centre National de la Recherche Scientifique (CNRS)-Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS), Beijing University of Chemical Technology, University of Leeds, Carnegie Mellon University [Pittsburgh] (CMU), Division of Nuclear Physics, Lund University [Lund], Universidade de Lisboa (ULISBOA), Aerodyne Research Inc., Harvard University [Cambridge], University of Eastern Finland, University of Tartu, University of California [Irvine] (UCI), University of California, Institute for Atmospheric and Climate Science [Zürich] (IAC), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), California Institute of Technology (CALTECH), University of Colorado [Boulder], School of Earth and Environmental Sciences [Manchester] (SEES), University of Manchester [Manchester], National Research Council of Canada (NRC), NASA Langley Research Center [Hampton] (LaRC), Universidade da Beira Interior, Ionicon GesmbH, Stockholm University, Helsinki Institute of Physics (HIP), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidade de Lisboa = University of Lisbon (ULISBOA), Harvard University, University of California [Irvine] (UC Irvine), University of California (UC), University of Beira Interior [Portugal] (UBI), INAR Physics, Air quality research group, Polar and arctic atmospheric research (PANDA), Global Atmosphere-Earth surface feedbacks, and Helsinki Institute of Physics

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, 010501 environmental sciences, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, 01 natural sciences, 114 Physical sciences, Organic molecules, chemistry.chemical_compound, SDG 13 - Climate Action, Cloud condensation nuclei, NOx, Research Articles, 0105 earth and related environmental sciences, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Multidisciplinary, Chemistry, Size dependent, SciAdv r-articles, 15. Life on land, respiratory system, Aerosol, 13. Climate action, Chemical physics, Particle growth, Nitrogen oxide, Research Article
Abstract

NOx is important for particle growth as it can participate in HOM formation and alter the HOM volatility distribution., Atmospheric new-particle formation (NPF) affects climate by contributing to a large fraction of the cloud condensation nuclei (CCN). Highly oxygenated organic molecules (HOMs) drive the early particle growth and therefore substantially influence the survival of newly formed particles to CCN. Nitrogen oxide (NOx) is known to suppress the NPF driven by HOMs, but the underlying mechanism remains largely unclear. Here, we examine the response of particle growth to the changes of HOM formation caused by NOx. We show that NOx suppresses particle growth in general, but the suppression is rather nonuniform and size dependent, which can be quantitatively explained by the shifted HOM volatility after adding NOx. By illustrating how NOx affects the early growth of new particles, a critical step of CCN formation, our results help provide a refined assessment of the potential climatic effects caused by the diverse changes of NOx level in forest regions around the globe.

Published
2020
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9. Low-volatility compounds contribute significantly to isoprene SOA under high-NO conditions

Author

Rebecca H. Schwantes, Tran B. Nguyen, John H. Seinfeld, Richard C. Flagan, Yuanlong Huang, Sophia M. Charan, Huajun Mai, Weimeng Kong, and Kelvin H. Bates

Subjects
Glyceric acid, Reaction conditions, chemistry.chemical_compound, chemistry, 13. Climate action, Computational chemistry, Inorganic ions, Global modeling, behavioral disciplines and activities, Volatility (chemistry), Isoprene, Aerosol, Organic nitrates
Abstract

Recent advances in our knowledge of the gas-phase oxidation of isoprene, the impact of chamber walls on secondary organic aerosol (SOA) mass yields, and aerosol measurement analysis techniques warrant re-evaluating SOA yields from isoprene. In particular, SOA from isoprene oxidation under high-NO conditions forms via two major pathways: (1) low-volatility nitrates and dinitrates (LV pathway) and (2) hydroxymethyl-methyl-α-lactone (HMML) reaction on a surface or the condensed phase of particles to form 2-methyl glyceric acid and its oligomers (2MGA pathway). These SOA production pathways respond differently to reaction conditions. Past chamber experiments generated SOA with varying contributions from these two unique pathways, leading to results that are difficult to interpret. This study examines the SOA yields from these two pathways independently, which improves the interpretation of previous results and provides further understanding of the relevance of chamber SOA yields to the atmosphere and regional/global modeling. Results suggest that low-volatility nitrates and dinitrates produce significantly more aerosol than previously thought; the SOA mass yield from the LV pathway is ≃ 0.15. Sufficient seed surface area at the start of the reaction is needed to limit the effects of vapor wall losses of low-volatility compounds and accurately measure the complete SOA mass yield. Under dry conditions, substantial amounts of SOA are formed from HMML ring-opening reactions with inorganic ions and HMML organic oligomerization processes. However, the lactone organic oligomerization reactions are suppressed under more atmospherically relevant humidity levels, where hydration of the lactone is more competitive. This limits the SOA formation potential from the 2MGA pathway to HMML ring-opening reactions with water or inorganic ions under typical atmospheric conditions. Due to the high isoprene SOA mass yield from the LV pathway measured in this work, we now roughly estimate that the LV pathway produces moderately more SOA mass than the 2MGA pathway under typical atmospheric conditions (RH = 70 %, T = 298 K, NO2/NO = 6, NO = 0.05 ppb, isoprene = 5 ppb, and OH = 1.5 × 106 molec cm−3). This suggests that in the atmosphere low-volatility compounds such as organic nitrates and dinitrates may contribute to isoprene SOA under high-NO conditions significantly more than previously thought, and thus deserve continued study.

Published
2019

10. Multicomponent new particle formation from sulfuric acid, ammonia, and biogenic vapors

Author

Lubna Dada, Clémence Rose, António Tomé, Kenneth S. Carslaw, Douglas R. Worsnop, Nina Sarnela, Juha Kangasluoma, Markku Kulmala, Paulus Salomon Bauer, Joachim Curtius, Paul M. Winkler, Victoria Hofbauer, Lauri Ahonen, Dexian Chen, Simon Schallhart, Jasmin Tröstl, Ugo Molteni, Antti Onnela, Arttu Ylisirniö, Josef Dommen, Sophia Brilke, Mario Simon, Chao Yan, Leonid Nichman, Neil M. Donahue, Huajun Mai, Veronika Pospisilova, Jasper Kirkby, Jonathan Duplissy, Tuomo Nieminen, Penglin Ye, Daniela Wimmer, Mikael Ehn, Christian Tauber, Jani Hakala, Roy L. Mauldin, Matti P. Rissanen, Lena Weitz, Jenni Kontkanen, Alexander L. Vogel, Stephany Buenrostro Mazon, Martin Breitenlechner, Xucheng He, Urs Baltensperger, Dominik Stolzenburg, Danielle C. Draper, Changhyuk Kim, Ilona Riipinen, Robert Wagner, Lukas Fischer, Annele Virtanen, Johanna Helm, Andreas Kürten, Xuemeng Chen, Rainer Volkamer, Felix Piel, Olga Garmash, Carla Frege, Angela Buchholz, Tuija Jokinen, Mao Xiao, Wei Nie, Armin Hansel, Andrea Baccarini, Kamalika Sengupta, Anne-Kathrin Bernhammer, Bernhard Baumgartner, António Amorim, Mingyi Wang, Michael J. Lawler, Monica Passananti, Martin Heinritzi, Olli Väisänen, Claudia Fuchs, Mikko Sipilä, Tuukka Petäjä, Simone Schuchmann, Christopher R. Hoyle, Andrea Christine Wagner, Katrianne Lehtipalo, Henning Finkenzeller, A.A. Dias, Qiaozhi Zha, Serge Mathot, Hamish Gordon, Lauriane L. J. Quéléver, Liine Heikkinen, Veli-Matti Kerminen, Andrea Ojdanic, Anton Bergen, F. Bianchi, Richard C. Flagan, Paul Scherrer Institute (PSI), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Finnish Meteorological Institute (FMI), University of Vienna [Vienna], Universidade de Lisboa = University of Lisbon (ULISBOA), Institute for Atmospheric and Environmental Sciences [Frankfurt/Main] (IAU), Goethe-University Frankfurt am Main, Ionicon GesmbH, Institut für Ionenphysik und Angewandte Physik - Institute for Ion Physics and Applied Physics [Innsbruck], Leopold Franzens Universität Innsbruck - University of Innsbruck, University of Eastern Finland, Carnegie Mellon University [Pittsburgh] (CMU), University of California [Irvine] (UC Irvine), University of California (UC), University of Colorado [Boulder], University of Leeds, Institut für Atmosphäre und Umwelt [Frankfurt/Main] (IAU), Goethe-Universität Frankfurt am Main, California Institute of Technology (CALTECH), Pusan National University, CERN [Genève], Stockholm University, School of Earth and Environmental Sciences [Manchester] (SEES), University of Manchester [Manchester], Boston College (BC), Nanjing University (NJU), Laboratory of Atmospheric Chemistry [Paul Scherrer Institute] (LAC), Laboratoire de Météorologie Physique (LaMP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), University of Beira Interior [Portugal] (UBI), Aerodyne Research Inc., Tempere University, Institute for Atmospheric and Earth System Research (INAR), INAR Physics, Aerosol-Cloud-Climate -Interactions (ACCI), Helsinki Institute of Physics, Polar and arctic atmospheric research (PANDA), University of Helsinki, Universidade de Lisboa (ULISBOA), University of California [Irvine] (UCI), University of California, Tampere University, and Physics

Subjects
inorganic chemicals, Atmospheric Science, DIMETHYLAMINE, 010504 meteorology & atmospheric sciences, chemistry.chemical_element, [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology, 010501 environmental sciences, OXIDATION, 114 Physical sciences, 01 natural sciences, CONDENSATION, chemistry.chemical_compound, Ammonia, SDG 13 - Climate Action, SPECTROMETER, ION, Dimethylamine, Research Articles, 1172 Environmental sciences, ComputingMilieux_MISCELLANEOUS, NOx, 0105 earth and related environmental sciences, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, GROWTH-RATES, Multidisciplinary, SciAdv r-articles, Sulfuric acid, Sulfur, Aerosol, SIZE, chemistry, 13. Climate action, Environmental chemistry, Atmospheric chemistry, Particle, NEUTRAL CLUSTER, Other, AEROSOL FORMATION, Research Article, NUCLEATION
Abstract

Atmospheric aerosol formation from biogenic vapors is strongly affected by air pollutants, like NOx, SO2, and NH3., A major fraction of atmospheric aerosol particles, which affect both air quality and climate, form from gaseous precursors in the atmosphere. Highly oxygenated organic molecules (HOMs), formed by oxidation of biogenic volatile organic compounds, are known to participate in particle formation and growth. However, it is not well understood how they interact with atmospheric pollutants, such as nitrogen oxides (NOx) and sulfur oxides (SOx) from fossil fuel combustion, as well as ammonia (NH3) from livestock and fertilizers. Here, we show how NOx suppresses particle formation, while HOMs, sulfuric acid, and NH3 have a synergistic enhancing effect on particle formation. We postulate a novel mechanism, involving HOMs, sulfuric acid, and ammonia, which is able to closely reproduce observations of particle formation and growth in daytime boreal forest and similar environments. The findings elucidate the complex interactions between biogenic and anthropogenic vapors in the atmospheric aerosol system.

Published
2018
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11. Scanning DMA Data Analysis II. Integrated DMA-CPC Instrument Response and Data Inversion

Author

Richard C. Flagan, John H. Seinfeld, Weimeng Kong, and Huajun Mai

Subjects
Electrical mobility, Plug flow, Materials science, 010504 meteorology & atmospheric sciences, Spectrometer, Detector, Ranging, 010501 environmental sciences, 01 natural sciences, Pollution, Transfer function, Computational physics, Differential mobility analyzer, Environmental Chemistry, General Materials Science, 0105 earth and related environmental sciences, Voltage
Abstract

Analysis of scanning electrical mobility spectrometer (SEMS) or SMPS data requires coupling the scanning differential mobility analyzer (DMA) transfer function with the response functions for the instrument plumbing and the detector. In the limit of plug flow (uniform velocity) within the DMA, the scanning DMA transfer function has the same form as that for constant voltage. Most SEMS/SMPS data analysis uses this model, though previous studies have shown that boundary layers distort the transfer function during scanning DMA measurements. Part I determined the instantaneous transfer function during scanning of the TSI Model 3081 A long column DMA by modeling the flows, fields, and particle trajectories within the actual DMA geometry. This study (Part II) combines that transfer function with empirical data on the efficiencies and delay time distributions of the plumbing and detector of the SEMS/SMPS to determine the instantaneous rate at which particles are counted, and integrates the count rate over the finite counting time interval to obtain the integrated SEMS/SMPS response function. Simulations using this geometrical model are compared with those obtained using traditional, idealized DMA models for scan rates ranging from slow (240 s) to very fast (10 s), and with measurements of monodisperse calibration aerosols. Data inversion studies show that both increasing and decreasing voltage scans can be used to determine the particle size distribution, even with fast scans. Copyright © 2018 American Association for Aerosol Research

Published
2018
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12. The nano-scanning electrical mobility spectrometer (nSEMS) and its application to size distribution measurements of 1.5-25 nm particles.

Author

Weimeng Kong, Amanatidis, Stavros, Huajun Mai, Changhyuk Kim, Schulze, Benjamin C., Yuanlong Huang, Lewis, Gregory S., Hering, Susanne V., Seinfeld, John H., and Flagan, Richard C.

Subjects
PARTICLE size determination, CLOUD condensation nuclei, SPECTROMETERS, DISCONTINUOUS precipitation, ION sources, SOFT X rays, CARBONACEOUS aerosols
Abstract

Particle size measurement in the low nanometer regime is of great importance to the study of cloud condensation nuclei formation and to better understand aerosol-cloud interaction. Here we present the design, modeling, and experimental characterization of the nano-scanning electrical mobility spectrometer (nSEMS), a recently developed instrument that probes particle physical properties in the 1.5 - 25 nm range. The nSEMS consists of a charge conditioner, a novel differential mobility analyzer, and a two-stage condensation particle counter (CPC). The charge conditioner employs a soft x-ray bipolar ion source in a compact housing designed to optimize both nanoparticle charging and transmission efficiency. The mobility analyzer, a radial opposed migration ion and aerosol classifier (ROMIAC), can classify nanometer-sized particles with minimal degradation of its resolution or diffusional losses. The ROMIAC operates on a dual high-voltage supply with fast polarity-switching capability to minimize sensitivity to variations in the chemical nature of the ions used to charge the aerosol. Particles transmitted through the charge conditioner and mobility analyzer are measured using a two-stage CPC. They are first activated in a fast-mixing diethylene glycol (DEG) stage before being counted by a second detection stage, an ADI MAGICTM water-based CPC. The transfer function of the integrated instrument is derived from both finite-element modeling and experimental characterization. The nSEMS performance has been evaluated during measurement of transient nucleation and growth events in the CLOUD atmospheric chamber at CERN. We show that the nSEMS can provide high time and size resolution measurement of nanoparticles, and can capture the critical aerosol dynamics of newly formed atmospheric particles. [ABSTRACT FROM AUTHOR]

Published
2021
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13. Design, simulation, and characterization of a radial opposed migration ion and aerosol classifier (ROMIAC)

Author

Richard C. Flagan, John H. Seinfeld, Huajun Mai, Wilton Mui, and Andrew J. Downard

Subjects
Physics, Electrical mobility, 010504 meteorology & atmospheric sciences, Mechanics, 010501 environmental sciences, 01 natural sciences, Pollution, Finite element method, Volumetric flow rate, Aerosol, Ion, Statistics, Environmental Chemistry, A priori and a posteriori, General Materials Science, Particle size, Classifier (UML), 0105 earth and related environmental sciences
Abstract

We present the design, simulation, and characterization of the radial opposed migration ion and aerosol classifier (ROMIAC), a compact differential electrical mobility classifier. We evaluate the performance of the ROMIAC using a combination of finite element modeling and experimental validation of two nearly identical instruments using tetra-alkyl ammonium halide mass standards and sodium chloride particles. Mobility and efficiency calibrations were performed over a wide range of particle diameters and flow rates to characterize ROMIAC performance under the range of anticipated operating conditions. The ROMIAC performs as designed, though performance deviates from that predicted using simplistic models of the instrument. The underlying causes of this non-ideal behavior are found through finite element simulations that predict the performance of the ROMIAC with greater accuracy than the simplistic models. It is concluded that analytical performance models based on idealized geometries, flows, and fields should not be relied on to make accurate a priori predictions about instrumental behavior if the actual geometry or fields deviate from the ideal assumptions. However, if such deviations are accurately captured, finite element simulations have the potential to predict instrumental performance. The present prototype of the ROMIAC maintains its resolution over nearly three orders of magnitude in particle mobility, obtaining sub-20 nm particle size distributions in a compact package with relatively low flow rate operation requirements. © 2017 American Association for Aerosol Research

Published
2017
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14. Under What Conditions Can Equilibrium Gas-Particle Partitioning Be Expected to Hold in the Atmosphere?

Author

Manabu Shiraiwa, Richard C. Flagan, Huajun Mai, and John H. Seinfeld

Subjects
Aerosols, Accommodation coefficient, Molecular diffusion, Atmospheric models, Chemistry, Atmosphere, Thermodynamics, General Chemistry, Models, Theoretical, Thermal diffusivity, Aerosol, Diffusion, Theoretical, Models, Environmental Chemistry, Gases, Particle Size, Volatilization, Volatility (chemistry), Dynamic equilibrium, Environmental Sciences
Abstract

The prevailing treatment of secondary organic aerosol formation in atmospheric models is based on the assumption of instantaneous gas-particle equilibrium for the condensing species, yet compelling experimental evidence indicates that organic aerosols can exhibit the properties of highly viscous, semisolid particles, for which gas-particle equilibrium may be achieved slowly. The approach to gas-particle equilibrium partitioning is controlled by gas-phase diffusion, interfacial transport, and particle-phase diffusion. Here we evaluate the controlling processes and the time scale to achieve gas-particle equilibrium as a function of the volatility of the condensing species, its surface accommodation coefficient, and its particle-phase diffusivity. For particles in the size range of typical atmospheric organic aerosols (∼50-500 nm), the time scale to establish gas-particle equilibrium is generally governed either by interfacial accommodation or particle-phase diffusion. The rate of approach to equilibrium varies, depending on whether the bulk vapor concentration is constant, typical of an open system, or decreasing as a result of condensation into the particles, typical of a closed system.

Published
2015
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15. Low-volatility compounds contribute significantly to isoprene SOA under high-NO conditions.

Author

Schwantes, Rebecca H., Charan, Sophia M., Bates, Kelvin H., Yuanlong Huang, Nguyen, Tran B., Huajun Mai, Weimeng Kong, Flagan, Richard C., and Seinfeld, John H.

Abstract

Recent advances in our knowledge of the gas-phase oxidation of isoprene, the impact of chamber walls on secondary organic aerosol (SOA) mass yields, and aerosol measurement analysis techniques warrant re-evaluating SOA yields from isoprene. In particular, SOA from isoprene oxidation under high-NO conditions forms via two major pathways: (1) low-volatility nitrates and dinitrates (LV pathway) and (2) hydroxymethyl-methyl-α-lactone (HMML) reaction on a surface or the condensed phase of particles to form 2-methyl glyceric acid and its oligomers (2MGA pathway). These SOA production pathways respond differently to reaction conditions. Past chamber experiments generated SOA with varying contributions from these two unique pathways, leading to results that are difficult to interpret. This study examines the SOA yields from these two pathways independently, which improves the interpretation of previous results and provides further understanding of the relevance of chamber SOA yields to the atmosphere and regional/global modeling. Results suggest that low-volatility nitrates and dinitrates produce significantly more aerosol than previously thought; the SOA mass yield from the LV pathway is ≃0.15. Sufficient seed surface area at the start of the reaction is needed to limit the effects of vapor wall losses of low-volatility compounds and accurately measure the complete SOA mass yield. Under dry conditions, substantial amounts of SOA are formed from HMML ring-opening reactions with inorganic ions and HMML organic oligomerization processes. However, the lactone organic oligomerization reactions are suppressed under more atmospherically relevant humidity levels, where hydration of the lactone is more competitive. This limits the SOA formation potential from the 2MGA pathway to HMML ring-opening reactions with water or inorganic ions under typical atmospheric conditions. Due to the high isoprene SOA mass yield from the LV pathway measured in this work, we now roughly estimate that the LV pathway produces moderately more SOA mass than the 2MGA pathway under typical atmospheric conditions (RH=70%, T=298K, NO2/NO=6, NO=0.05ppb, isoprene=5ppb, and OH=1.5×106moleccm-3). This suggests that in the atmosphere low-volatility compounds such as organic nitrates and dinitrates may contribute to isoprene SOA under high-NO conditions significantly more than previously thought, and thus deserve continued study. [ABSTRACT FROM AUTHOR]

Published
2019
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16. Rapid growth of organic aerosol nanoparticles over a wide tropospheric temperature range.

Author

Stolzenburg, Dominik, Bauer, Paulus S., Baumgartner, Bernhard, Brilke, Sophia, Ojdanic, Andrea, Tauber, Christian, Winkler, Paul M., Draper, Danielle C., Lawler, Michael, Smith, James N., Finkenzeller, Henning, Hoyle, Christopher R., Huajun Mai, Flagan, Richard C., Changhyuk Kim, Wei Nie, Nieminen, Tuomo, Fischer, Lukas, Leiminger, Markus, and Mentler, Bernhard

Subjects
NANOPARTICLES, AEROSOLS & the environment, CLOUD condensation nuclei, VOLATILE organic compounds, OZONOLYSIS, CLOUD droplets
Abstract

Nucleation and growth of aerosol particles from atmospheric vapors constitutes a major source of global cloud condensation nuclei (CCN). The fraction of newly formed particles that reaches CCN sizes is highly sensitive to particle growth rates, especially for particle sizes <10 nm, where coagulation losses to larger aerosol particles are greatest. Recent results show that some oxidation products from biogenic volatile organic compounds are major contributors to particle formation and initial growth. However, whether oxidized organics contribute to particle growth over the broad span of tropospheric temperatures remains an open question, and quantitative mass balance for organic growth has yet to be demonstrated at any temperature. Here, in experiments performed under atmospheric conditions in the Cosmics Leaving Outdoor Droplets (CLOUD) chamber at the European Organization for Nuclear Research (CERN), we show that rapid growth of organic particles occurs over the range from -25 °C to 25 °C. The lower extent of autoxidation at reduced temperatures is compensated by the decreased volatility of all oxidized molecules. This is confirmed by particle-phase composition measurements, showing enhanced uptake of relatively less oxygenated products at cold temperatures. We can reproduce the measured growth rates using an aerosol growth model based entirely on the experimentally measured gas-phase spectra of oxidized organic molecules obtained from two complementary mass spectrometers. We show that the growth rates are sensitive to particle curvature, explaining widespread atmospheric observations that particle growth rates increase in the singledigit-nanometer size range. Our results demonstrate that organic vapors can contribute to particle growth over a wide range of tropospheric temperatures from molecular cluster sizes onward. [ABSTRACT FROM AUTHOR]

Published
2018
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17. Under What Conditions Can Equilibrium Gas-Particle Partitioning Be Expected to Hold in the Atmosphere?

Author

Huajun Mai, Shiraiwa, Manabu, Flagan, Richard C., and Seinfeld, John H.

Subjects
*CHEMICAL equilibrium, *ATMOSPHERIC chemistry, *ATMOSPHERIC aerosols, *ORGANIC compounds & the environment, *CONDENSATION (Meteorology)
Abstract

The prevailing treatment of secondary organic aerosol formation in atmospheric models is based on the assumption of instantaneous gas-particle equilibrium for the condensing species, yet compelling experimental evidence indicates that organic aerosols can exhibit the properties of highly viscous, semisolid particles, for which gas-particle equilibrium may be achieved slowly. The approach to gas-particle equilibrium partitioning is controlled by gas-phase diffusion, interfacial transport, and particle-phase diffusion. Here we evaluate the controlling processes and the time scale to achieve gas-particle equilibrium as a function of the volatility of the condensing species, its surface accommodation coefficient, and its particle-phase diffusivity. For particles in the size range of typical atmospheric organic aerosols (~50-500 nm), the time scale to establish gas-particle equilibrium is generally governed either by interfacial accommodation or particle-phase diffusion. The rate of approach to equilibrium varies, depending on whether the bulk vapor concentration is constant, typical of an open system, or decreasing as a result of condensation into the particles, typical of a closed system. [ABSTRACT FROM AUTHOR]

Published
2015
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18. Rapid growth of organic aerosol nanoparticles over a wide tropospheric temperature range

Author

Michael J. Lawler, Christian Tauber, Changhyuk Kim, António Tomé, Martin Heinritzi, Olga Garmash, Douglas R. Worsnop, Bernhard Baumgartner, Daniela Wimmer, Claudia Fuchs, Imad El Haddad, Richard C. Flagan, Mao Xiao, Xucheng He, Victoria Hofbauer, Meredith Schervish, Wei Nie, Armin Hansel, Lubna Dada, Matti P. Rissanen, Paul M. Winkler, Serge Mathot, Dominik Stolzenburg, Paulus Salomon Bauer, Nina Sarnela, Hamish Gordon, Ugo Molteni, Antti Onnela, Qiaozhi Zha, Monica Passananti, Mario Simon, Huajun Mai, Antonio Dias, Markus Leiminger, Dexian Chen, Markku Kulmala, Andreas Kürten, Mingyi Wang, Sophia Brilke, Martin Breitenlechner, Urs Baltensperger, Simon Schallhart, Danielle C. Draper, Jonathan Duplissy, Penglin Ye, Tuomo Nieminen, Andrea Baccarini, Bernhard Mentler, Jenni Kontkanen, Joachim Curtius, António Amorim, Janne Lampilahti, Lauri Ahonen, James N. Smith, Carla Frege, Jasper Kirkby, Tuukka Petäjä, Lukas Fischer, Johanna Helm, Stephany Buenrostro Mazon, Chao Yan, F. Bianchi, Lauriane L. J. Quéléver, Andrea Ojdanic, Andrea Christine Wagner, Christopher R. Hoyle, Katrianne Lehtipalo, Henning Finkenzeller, Neil M. Donahue, Lena Weitz, Josef Dommen, Alexander L. Vogel, Robert Wagner, John B. Nowak, Anton Bergen, Institute for Atmospheric and Earth System Research (INAR), Department of Physics, Aerosol-Cloud-Climate -Interactions (ACCI), Polar and arctic atmospheric research (PANDA), and Seinfeld, John H.

Subjects
IONS, CLOUD experiment, Materials science, 010504 meteorology & atmospheric sciences, Nucleation, Analytical chemistry, Nanoparticle, aerosol formation, 010501 environmental sciences, GASES, 01 natural sciences, 114 Physical sciences, Ion, Troposphere, CONDENSATION, CHEMISTRY, volatile organic compounds, MD Multidisciplinary, PARTICLE FORMATION, Aerosols, nanoparticle growth, Volatile organic compounds, ddc:550, Cloud condensation nuclei, 1172 Environmental sciences, 0105 earth and related environmental sciences, Multidisciplinary, Aerosol, Aerosol formation, Nanoparticle growth, PRODUCTS, 13. Climate action, ACID, Volatility (chemistry), CHAMBER, aerosols, NUCLEATION
Abstract

Nucleation and growth of aerosol particles from atmospheric vapors constitutes a major source of global cloud condensation nuclei (CCN). The fraction of newly formed particles that reaches CCN sizes is highly sensitive to particle growth rates, especially for particle sizes, Proceedings of the National Academy of Sciences of the United States of America, 115 (37), ISSN:0027-8424, ISSN:1091-6490

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19. Molecular understanding of new-particle formation from α-pinene between −50 and +25 °C

Author

Houssni Lamkaddam, Manuel Granzin, Jani Hakala, Dexian Chen, Xu-Cheng He, Siegfried Schobesberger, Danielle C. Draper, Qing Ye, Neil M. Donahue, Lubna Dada, Antonio Dias, Guillaume Marie, Victoria Hofbauer, Matti P. Rissanen, Ugo Molteni, Christian Tauber, Gerhard Steiner, Eva Partoll, Alexander L. Vogel, Markus Leiminger, Antti Onnela, Joachim Curtius, Robert Wagner, Sophia Brilke, Mikko Sipilä, Lisa Beck, Chuan P. Lee, Wei Nie, Armin Hansel, Ananth Ranjithkumar, Imad El-Haddad, Xueqin Zhou, Urs Baltensperger, Dominik Stolzenburg, Paul M. Winkler, Joao Almeida, Yusheng Wu, Chao Yan, Stefan K. Weber, Rima Baalbaki, Lauriane L. J. Quéléver, Biwu Chu, Markku Kulmala, Rainer Volkamer, Simone Schuchmann, Marcel Zauner-Wieczorek, Birte Rörup, Simon Schallhart, Paulus Salomon Bauer, António Tomé, Wiebke Scholz, Mingyi Wang, Steffen Bräkling, Christopher R. Hoyle, Yonghong Wang, Anton Bergen, Mario Simon, Martin Heinritzi, Jiali Shen, Huajun Mai, Andreas Kürten, Andrea Baccarini, Bernhard Mentler, Loic Gonzalez-Carracedo, Richard C. Flagan, Douglas R. Worsnop, Miguel Vazquez-Pufleau, Jonathan Duplissy, Penglin Ye, Joschka Pfeifer, Lukas Fischer, Josef Dommen, Jasper Kirkby, Ruby Marten, Dongyu S. Wang, Andrea C. Wagner, Lucía Caudillo, Hamish Gordon, Katrianne Lehtipalo, Henning Finkenzeller, Changhyuk Kim, Yuri Stozhkov, Yee J. Tham, Leonid Nichman, Weimeng Kong, Tuukka Petäjä, Carla Frege, Mao Xiao, Hanna E. Manninen, F. Bianchi, M. V. Philippov, and Andrea Ojdanic

Subjects
Atmospheric Science, Chemical ionization, 010504 meteorology & atmospheric sciences, Autoxidation, Vapor pressure, Analytical chemistry, Nucleation, Sulfuric acid, 010402 general chemistry, 01 natural sciences, 0104 chemical sciences, 3. Good health, Aerosol, chemistry.chemical_compound, chemistry, 13. Climate action, Oxidation state, Volatility (chemistry), 0105 earth and related environmental sciences
Abstract

Highly oxygenated organic molecules (HOMs) contribute substantially to the formation and growth of atmospheric aerosol particles, which affect air quality, human health and Earth's climate. HOMs are formed by rapid, gas-phase autoxidation of volatile organic compounds (VOCs) such as α-pinene, the most abundant monoterpene in the atmosphere. Due to their abundance and low volatility, HOMs can play an important role in new-particle formation (NPF) and the early growth of atmospheric aerosols, even without any further assistance of other low-volatility compounds such as sulfuric acid. Both the autoxidation reaction forming HOMs and their NPF rates are expected to be strongly dependent on temperature. However, experimental data on both effects are limited. Dedicated experiments were performed at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber at CERN to address this question. In this study, we show that a decrease in temperature (from +25 to −50 ∘C) results in a reduced HOM yield and reduced oxidation state of the products, whereas the NPF rates (J1.7 nm) increase substantially. Measurements with two different chemical ionization mass spectrometers (using nitrate and protonated water as reagent ion, respectively) provide the molecular composition of the gaseous oxidation products, and a two-dimensional volatility basis set (2D VBS) model provides their volatility distribution. The HOM yield decreases with temperature from 6.2 % at 25 ∘C to 0.7 % at −50 ∘C. However, there is a strong reduction of the saturation vapor pressure of each oxidation state as the temperature is reduced. Overall, the reduction in volatility with temperature leads to an increase in the nucleation rates by up to 3 orders of magnitude at −50 ∘C compared with 25 ∘C. In addition, the enhancement of the nucleation rates by ions decreases with decreasing temperature, since the neutral molecular clusters have increased stability against evaporation. The resulting data quantify how the interplay between the temperature-dependent oxidation pathways and the associated vapor pressures affect biogenic NPF at the molecular level. Our measurements, therefore, improve our understanding of pure biogenic NPF for a wide range of tropospheric temperatures and precursor concentrations.

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