HR: 1340h
AN: A33D-1563    [Abstracts]
TI: Chemical Cycling of Nitrogen Oxides on Urban Films
AU: * Donaldson, J
EM: jdonalds@chem.utoronto.ca
AF: Department of Chemistry, University of Toronto, 80 St George St, Toronto, ON M5S 3H6, Canada
AU: Handley, S
EM: shandley@chem.utoronto.ca
AF: Department of Chemistry, University of Toronto, 80 St George St, Toronto, ON M5S 3H6, Canada
AU: Clifford, D
EM: dcliffor@chem.utoronto.ca
AF: Department of Chemistry, University of Toronto, 80 St George St, Toronto, ON M5S 3H6, Canada
AU: Styler, S
EM: sstyler@chem.utoronto.ca
AF: Department of Chemistry, University of Toronto, 80 St George St, Toronto, ON M5S 3H6, Canada
AB: The films coating urban impervious surfaces have been found to be comprised of about 7 percent inorganic nitrate and about 10 percent organic compounds (by mass). A simple steady-state analysis of the lifetime of the nitrate in the film suggests the existence of a loss process(es) in addition to washout by rainfall. Gas phase nitric acid can be taken up in organic films and lower the film pH. Photolysis of nitrated films using actinic illumination causes loss both of protons and of nitrate anions. This is likely due to a combination of direct and indirect (photosensitized) photochemistry involving nitrate ions, yielding gas phase HONO and / or NO2.
DE: 0317 Chemical kinetic and photochemical properties
DE: 0322 Constituent sources and sinks
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting