| Title: | Secondary organic aerosol from aqueous reactions of green leaf volatiles with organic triplet excited states and singlet molecular oxygen |
| Author(s): | Richards-Henderson NK; Pham AT; Kirk BB; Anastasio C; |
| Address: | "Department of Land, Air and Water Resources, University of California - Davis , 1 Shields Avenue, Davis, California 95616, United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Vegetation emits a class of oxygenated hydrocarbons--the green leaf volatiles (GLVs)--under stress or damage. Under foggy conditions GLVs might be a source of secondary organic aerosol (SOA) via aqueous reactions with hydroxyl radical (OH), singlet oxygen ((1)O2*), and excited triplet states ((3)C*). To examine this, we determined the aqueous kinetics and SOA mass yields for reactions of (3)C* and (1)O2* with five GLVs: methyl jasmonate (MeJa), methyl salicylate (MeSa), cis-3-hexenyl acetate (HxAc), cis-3-hexen-1-ol (HxO), and 2-methyl-3-butene-2-ol (MBO). Second-order rate constants with (3)C* and (1)O2* range from (0.13-22) x 10(8) M(-1) s(-1) and (8.2-60) x 10(5) M(-1) s(-1) at 298 K, respectively. Rate constants with (3)C* are independent of temperature, while values with (1)O2* show significant temperature dependence (Ea = 20-96 kJ mol(-1)). Aqueous SOA mass yields for oxidation by (3)C* are (84 +/- 7)%, (80 +/- 9)%, and (38 +/- 18)%, for MeJa, MeSa, and HxAc, respectively; we did not measure yields for other conditions because of slow kinetics. The aqueous production of SOA from GLVs is dominated by (3)C* and OH reactions, which form low volatility products at a rate that is approximately half that from the parallel gas-phase reactions of GLVs" |
| Keywords: | Acetates/chemistry Aerosols/*chemistry Cyclopentanes/chemistry Hexanols/chemistry Hydroxyl Radical Kinetics Oxygen/chemistry Oxylipins/chemistry Pentanols/chemistry Plant Leaves/*chemistry Salicylates/chemistry Singlet Oxygen Temperature Volatile Organic; |
| Notes: | "MedlineRichards-Henderson, Nicole K Pham, Andrew T Kirk, Benjamin B Anastasio, Cort eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2014/11/27 Environ Sci Technol. 2015 Jan 6; 49(1):268-76. doi: 10.1021/es503656m. Epub 2014 Dec 11" |
