title: Photochemical aging of secondary organic aerosols generated from the photooxidation of polycyclic aromatic hydrocarbons in the gas-phase.
abstract: Aging processes of secondary organic aerosol (SOA) may be a source of oxygenated organic aerosols; however, the chemical processes involved remain unclear. In this study, we investigate photochemical aging of SOA produced by the gas-phase oxidation of naphthalene by hydroxyl radicals and acenaphthylene by ozone. We monitored the SOA composition using a high-resolution time-of-flight aerosol mass spectrometer. We initiated SOA aging with UV photolysis alone and with OH radicals in the presence or absence of light and at different NOx levels. For naphthalene, the organic composition of the particulate phase seems to be dominated by highly oxidized compounds such as carboxylic acids, and aging data may be consistent with diffusion limitations. For acenaphthylene, the fate of oxidized products and the moderately oxidized aerosol seem to indicate that functionalization reactions might be the main aging process were initiated by the cumulative effect of light and OH radicals.
authors: †University of Bordeaux, EPOC, UMR 5805, F-33405 Talence cedex, France.|‡CNRS, EPOC, UMR 5805, F-33405 Talence cedex, France.
authors: Matthieu
authors: M
authors: Riva
authors: §Center for Atmospheric Particles Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
authors: Ellis S
authors: ES
authors: Robinson
authors: †University of Bordeaux, EPOC, UMR 5805, F-33405 Talence cedex, France.|‡CNRS, EPOC, UMR 5805, F-33405 Talence cedex, France.
authors: Emilie
authors: E
authors: Perraudin
authors: §Center for Atmospheric Particles Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
authors: Neil M
authors: NM
authors: Donahue
authors: †University of Bordeaux, EPOC, UMR 5805, F-33405 Talence cedex, France.|‡CNRS, EPOC, UMR 5805, F-33405 Talence cedex, France.
authors: Eric
authors: E
authors: Villenave
mesh_terms: D000336:Aerosols / Q000032:analysis* / Q000737:chemistry; D005740:Gases / Q000737:chemistry*; D008027:Light; D013058:Mass Spectrometry; D009281:Naphthalenes / Q000737:chemistry; D010084:Oxidation-Reduction / Q000528:radiation effects; D010126:Ozone / Q000737:chemistry; D052638:Particulate Matter / Q000032:analysis; D055668:Photochemical Processes; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D013997:Time Factors
chemical_list: D000336:Aerosols; D005740:Gases; D009281:Naphthalenes; D052638:Particulate Matter; D011084:Polycyclic Aromatic Hydrocarbons; C031721:naphthalene; D010126:Ozone