Title: | "Monoterpene Photooxidation in a Continuous-Flow Chamber: SOA Yields and Impacts of Oxidants, NO(x), and VOC Precursors" |
Author(s): | Liu J; D'Ambro EL; Lee BH; Schobesberger S; Bell DM; Zaveri RA; Zelenyuk A; Thornton JA; Shilling JE; |
Address: | "Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, Washington 99352, United States. School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China. Department of Chemistry, University of Washington, Seattle, Washington 98195, United States. Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195, United States" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "Monoterpene photooxidation plays an important role in secondary organic aerosol (SOA) formation in the atmosphere. The low-volatility products can enhance new particle formation and particle growth and thus influence climate feedback. Here, we present the results of alpha-pinene and Delta-3-carene photooxidation experiments conducted in continuous-flow mode in an environmental chamber under several reaction conditions. The roles of oxidants, addition of NO, and VOC molecular structure in influencing SOA yield are illustrated. SOA yield from alpha-pinene photooxidation shows a weak dependence on H(2)O(2) concentration, which is a proxy for HO(2) concentration. The high O/C ratios observed in the alpha-pinene photooxidation products suggest the production of highly oxygenated organic molecules (HOM). Addition of ozone to the chamber during low-NO(x) photooxidation experiments leads to higher SOA yield. With the addition of NO, the production of N-containing HOMs is enhanced and the SOA yield shows a modest, nonlinear dependence on the input NO concentration. Carene photooxidation leads to higher SOA yield than alpha-pinene under similar reaction conditions, which agrees with the lower volatility retrieved from evaporation kinetics experiments. These results improve the understanding of SOA formation from monoterpene photooxidation and could be applied to refine the representation of biogenic SOA formation in models" |
Keywords: | Aerosols/chemistry *Air Pollutants/analysis Hydrogen Peroxide Monoterpenes/chemistry Oxidants Oxidation-Reduction *Volatile Organic Compounds NOx effect chamber monoterpene photooxidation secondary organic aerosol; |
Notes: | "MedlineLiu, Jiumeng D'Ambro, Emma L Lee, Ben Hwan Schobesberger, Siegfried Bell, David M Zaveri, Rahul A Zelenyuk, Alla Thornton, Joel A Shilling, John E eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2022/08/18 Environ Sci Technol. 2022 Sep 6; 56(17):12066-12076. doi: 10.1021/acs.est.2c02630. Epub 2022 Aug 17" |