抄録
Photochemical aerosol formation from cycloalkene-NOx mixtures was studied with cycloalkene initial concentration about 0.3 ppm and cycloalkene/NOx ratio about 5. Compounds studied extended from cyclopentene to cyclooctene including a few methyl derivatives. The aerosol was found to be produced mostly through the cycloalkene-O3 reaction except for the case of cyclooctene, in which the OH reaction contributed significantly. The aerosol yields from the O3 reaction were determined on the basis of the volume concentration, and they showed an increasing trend with increasing carbon number. The yields were further pursued in a cycloalkene concentration range from 0.1 to 0.01 ppm by making the O3 reaction in the dark. The yields for 0.1 ppm were found to be generally smaller than those for 0.3 ppm in accordance with our previous experiment on cyclohexene, but they stayed constant in the concentration range down to 0.01 ppm. The average carbonmass basis percent yields were much smaller than formerly believed. However they gave a consistent connection between the existing field data on cycloalkene and dicarboxylic acid concentrations.
