光照强度和光源对间二甲苯/氮氧化物光氧化体系中二次有机气溶胶形成的影响。

Light intensity and light source influence on secondary organic aerosol formation for the m-xylene/NO(x) photooxidation system.

作者信息

Warren Bethany, Song Chen, Cocker David R

机构信息

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.

出版信息

Environ Sci Technol. 2008 Aug 1;42(15):5461-6. doi: 10.1021/es702985n.

DOI:10.1021/es702985n

PMID:18754461

Abstract

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.

摘要

进行了一系列间二甲苯/氮氧化物光氧化实验，以确定光强和辐射光谱对加州大学河滨分校/CE-CERT环境舱内二次有机气溶胶（SOA）形成的影响。该环境舱配备了80盏115瓦的黑光灯和一盏可变电压的200千瓦氩弧灯，后者发射的波长光谱更接近自然光。随着光强的增加，SOA的形成显著增加，光强以二氧化氮到一氧化氮的光解速率（k1）衡量，从0.09增加到0.26分钟-1。在消耗相似量的间二甲苯时，对于k1为0.09分钟-1的情况，氩弧灯产生的SOA比黑光灯大约多20%。这些结果可能有助于解释不同环境舱之间SOA形成的差异，以及环境大气中测量的SOA与环境舱预测值之间的差异。