Aerosols, organic photochemistry

Marine Organic Photochemistry From the Sea Surface to Marine Aerosols 3... 

Volkamer R, Ziemaim PJ, Molina MJ (2009) Secondary organic aerosol formation fi om acetylene (C(2)H(2)) seed effect on SOA yields due to organic photochemistry in the aerosol aqueous phase. Atmos Chem Phys 9(6) 1907-1928... 

Feilberg, A., and T. Nielsen, Model Systems to Simulate Photochemistry in the Organic Liquid Phase of Combustion Aerosols, presented at the 6th FECS Conference on Chemistry and the Environment, Atmospheric Chemistry and Air Pollution, University of Copenhagen, Copenhagen, Denmark, August 26-28, 1998. 

Future directions using the above-described approach are envisioned (i) applications to photochemistry in condensed phases among the possibilities are the simulation of reactions in solvents, reactions in solids and liquids, and aerosols (ii) applications to reactions of large organic carbonyls, as an extension to the described work here (iii) studies on different carbonyls such as ketones and carboxylic acids. 

Shi JP, Khan A A, Harrison RM (1999) Measurements of ultrafine particle concentration and size distribution in the urban atmosphere. Sci Total Environ 235 51-64 Siefert RL, Pehkonen SO, Erel Y, Hoffmatm MR (1994) Iron photochemistry of aqueous suspensions of ambient aerosol with added organic-acids. Geochim Cosmochim Acta 58 3271-3279 Sievering H, Boatman J, Gorman E, Kim Y, Anderson L, Ennis G, Luria M, Pandis S (1992) Removal of sulphur from the marine boimdaiy layer by ozone oxidation in sea-salt aerosols. Nature 360 571-573 Siffert C, Sulzberger B (1991) Light-induced dissolution of hematite in the presence of oxalate-A case-study. Langmuir 7 1627-1634... 

Other light-absorbing compounds that may be present in marine aerosol particles and contribute to photochemistry include transition metals, nitrate anions, amines, polyaromatic hydrocarbons, and other organic molecules. Transition metal complexes (including iron, copper, manganese, nickel) are... 

Furthermore, the adsorption of organics onto the aerosol matrix can modify their reactivity through catalytic effects, induced by constituents of that matrix. The suppression of photochemistry of PAH, adsorbed onto coal fly-ash (Korfmacher et al. (lOG)), has been tentatively explained by the role of transition metal ions at the surface in quenching excited states formed upon irradiation. 

Aerosols are also important in stratospheric photochemistry. They are thought to be formed as a result of the oxidation of dimethyl sulphide in the troposphere. This is formed from decaying organic matter (e.g. oceanic algae) and is emitted into the air where it breaks down to form carbonyl sulfide COS. This is chemically stable... 

Keywords Cloud chemistry Dust Heterogeneous chemistry Ice photochemistry Organic aerosols Urban grime Vibrational overtone absorption... 

Both photosensitized reacticms and heterogeneous photocatalysis have been the focus of many studies and reviews for the degradation of organic and inorganic species in natural terrestrial surface water. This review will discuss their potential importance in the atmosphere for two distinct cases — photochemistry of mineral dust (which contains oxides able to initiate photocatalysis) and organic or carbonaceous aerosols (which contain aromatic compounds or humic like substances able to act as photosensitizers). Additionally, direct photochemistry of unconventional precursors, i.e., iron-dicarboxylic acid anionic complexes, will also be dealt with. 

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