Light intensity and light source influence on secondary organic aerosol formation for the m-xylene/NO(x) photooxidation system.
A series of m-xylene/NO(x) photooxidation experiments were conducted to determine the influence of light intensity and radiation spectrum on secondary organic aerosol (SOA) formation within the UC Riverside/CE-CERT environmental chamber. The environmental chamber is equipped with 80 115-W black lights and a variable voltage 200 kW argon arc lamp that emits a wavelength spectrum more similar to natural light. SOA formation increased significantly with light intensity, measured as the photolysis rate of NO2 to NO (k1), increased from 0.09 to 0.26 min(-1). The argon arc lamp produced approximately 20% more SOA than black lights at a k1 of 0.09 min(-1) for similar amounts of m-xylene consumed. These results may help explain the variation of SOA formation between environmental chambers and the differences between measured SOA in the ambient atmosphere versus environmental chamber predictions.
Warren
Bethany
B
Department of Chemical and Environmental Engineering, Bourns College of Engineering, Center for Environmental Research and Technology (CE-CERT), University of California, Riverside, California 92521, USA.
Song
Chen
C
Cocker
David R
DR