Jens Top, Natasha M. Garner, Félix Sari Doré, Yanjun Zhang, Cecilie Carstens, Clément Dubois, Fabian Mahrt, Markus Ammann, André S. H. Prévôt, Matthieu Riva, Imad El Haddad and David M. Bell*,
{"title":"相对湿度和种子颗粒对α-蒎烯二次有机气溶胶分子组成的影响","authors":"Jens Top, Natasha M. Garner, Félix Sari Doré, Yanjun Zhang, Cecilie Carstens, Clément Dubois, Fabian Mahrt, Markus Ammann, André S. H. Prévôt, Matthieu Riva, Imad El Haddad and David M. Bell*, ","doi":"10.1021/acsestair.5c00064","DOIUrl":null,"url":null,"abstract":"<p >Secondary organic aerosol (SOA), a major component of submicrometer particles, is critical to the climate and human health. SOA can form through nucleation of low-volatility organic compounds, following atmospheric oxidation, or by condensing these vapors onto existing particles. In either of these cases, the formation of SOA particles could be affected by atmospheric conditions (e.g., relative humidity (RH)) and particle liquid water content. This study examines the effects of RH on the formation and composition of SOA from dark α-pinene (C<sub>10</sub>H<sub>16</sub>) ozonolysis, as a canonical system, with or without ammonium sulfate (AS, (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>) seed particles across varying RH levels. Using online extractive electrospray ionization mass spectrometry, we identified monomers (C<sub>7–10</sub>) and dimers (C<sub>15–20</sub>) in the SOA with high chemical and temporal resolution. In both cases, high RH (>90%) promotes dimer formation in the particle phase, while they appear at the beginning of the experiment when (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> seeds are present. The prompt increase in dimers in high RH seed containing experiments (60–65% dimers), which are absent at low RH (10%), suggests that intraparticle reactions are responsible for the dimer formation.</p><p >Both water and the presence of ammonium sulfate seed particles impact the composition of condensed-phase products in α-pinene secondary organic aerosol formed via dark ozonolysis.</p>","PeriodicalId":100014,"journal":{"name":"ACS ES&T Air","volume":"2 8","pages":"1565–1574"},"PeriodicalIF":0.0000,"publicationDate":"2025-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acsestair.5c00064","citationCount":"0","resultStr":"{\"title\":\"Influence of Relative Humidity and Seed Particles on Molecular Composition of α-Pinene Secondary Organic Aerosol\",\"authors\":\"Jens Top, Natasha M. Garner, Félix Sari Doré, Yanjun Zhang, Cecilie Carstens, Clément Dubois, Fabian Mahrt, Markus Ammann, André S. H. Prévôt, Matthieu Riva, Imad El Haddad and David M. Bell*, \",\"doi\":\"10.1021/acsestair.5c00064\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >Secondary organic aerosol (SOA), a major component of submicrometer particles, is critical to the climate and human health. SOA can form through nucleation of low-volatility organic compounds, following atmospheric oxidation, or by condensing these vapors onto existing particles. In either of these cases, the formation of SOA particles could be affected by atmospheric conditions (e.g., relative humidity (RH)) and particle liquid water content. This study examines the effects of RH on the formation and composition of SOA from dark α-pinene (C<sub>10</sub>H<sub>16</sub>) ozonolysis, as a canonical system, with or without ammonium sulfate (AS, (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub>) seed particles across varying RH levels. Using online extractive electrospray ionization mass spectrometry, we identified monomers (C<sub>7–10</sub>) and dimers (C<sub>15–20</sub>) in the SOA with high chemical and temporal resolution. In both cases, high RH (>90%) promotes dimer formation in the particle phase, while they appear at the beginning of the experiment when (NH<sub>4</sub>)<sub>2</sub>SO<sub>4</sub> seeds are present. The prompt increase in dimers in high RH seed containing experiments (60–65% dimers), which are absent at low RH (10%), suggests that intraparticle reactions are responsible for the dimer formation.</p><p >Both water and the presence of ammonium sulfate seed particles impact the composition of condensed-phase products in α-pinene secondary organic aerosol formed via dark ozonolysis.</p>\",\"PeriodicalId\":100014,\"journal\":{\"name\":\"ACS ES&T Air\",\"volume\":\"2 8\",\"pages\":\"1565–1574\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2025-07-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://pubs.acs.org/doi/pdf/10.1021/acsestair.5c00064\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"ACS ES&T Air\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://pubs.acs.org/doi/10.1021/acsestair.5c00064\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS ES&T Air","FirstCategoryId":"1085","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsestair.5c00064","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Influence of Relative Humidity and Seed Particles on Molecular Composition of α-Pinene Secondary Organic Aerosol
Secondary organic aerosol (SOA), a major component of submicrometer particles, is critical to the climate and human health. SOA can form through nucleation of low-volatility organic compounds, following atmospheric oxidation, or by condensing these vapors onto existing particles. In either of these cases, the formation of SOA particles could be affected by atmospheric conditions (e.g., relative humidity (RH)) and particle liquid water content. This study examines the effects of RH on the formation and composition of SOA from dark α-pinene (C10H16) ozonolysis, as a canonical system, with or without ammonium sulfate (AS, (NH4)2SO4) seed particles across varying RH levels. Using online extractive electrospray ionization mass spectrometry, we identified monomers (C7–10) and dimers (C15–20) in the SOA with high chemical and temporal resolution. In both cases, high RH (>90%) promotes dimer formation in the particle phase, while they appear at the beginning of the experiment when (NH4)2SO4 seeds are present. The prompt increase in dimers in high RH seed containing experiments (60–65% dimers), which are absent at low RH (10%), suggests that intraparticle reactions are responsible for the dimer formation.
Both water and the presence of ammonium sulfate seed particles impact the composition of condensed-phase products in α-pinene secondary organic aerosol formed via dark ozonolysis.