Title: | [Characteristics of ambient VOCs and their role in O3 formation: a typical air pollution episode in Shanghai urban area] |
Author(s): | Cui HX; Wu YM; Gao S; Duan YS; Wang DF; Zhang YH; Fu QY; |
Address: | "Shanghai Environmental Monitoring Center, Shanghai 200030, China. cuihx@semc.gov.cn" |
ISSN/ISBN: | 0250-3301 (Print) 0250-3301 (Linking) |
Abstract: | "The concentration, speciation and chemical reactivity of ambient volatile organic compounds (VOCs) in shanghai city were analyzed and measured by using online gas chromatography with flame ionization detection systems (GC-FID) during a typical air pollution episode (from Oct. 30th to Nov. 2nd, 2010) and 55 kinds of VOCs were detected. The results show that averaged concentrations of VOCs was 27 x 10(-9) before the episode, and then dramatically increased by 3 times (87 x 10(-9)) in the episode than the former, the main components were alkanes (35.2 x 10(-9)), aromatics (30.0 x 10(-9)), alkenes (21.6 x 10(-9)). Furthermore, the maximum ozone formation potential (PhiOFP) is analyzed and showed that PhiOFP (in the episode) > PhiOFP (after the episode) PhiOFP (before the episode). Before the episode, the percent of PhiOFP for aromatics 53.0% , alkenes 36. 1% and alkanes 11.7%; in the episode, the percent of PhiOFP for aromatics 54.7%, alkenes 36.7% and alkanes 9.8%; after the episode, the percent of PhiOFP for alkenes 52.7%, aromatics 36.0% and alkanes 13.2%. Alkenes (C2-C4) and aromatics (C6-C8) are the main components for the ozone formation, namely toluene, m,p-xylene, 1,3-butadiene, propene, ethene et al. In addition, the relationship is negative and nonlinear between the O3 and PhiOFP. And efficiencies of PhiOFP formed into O3 are below 20. 0% in different stage of episode. This is very important and meaningful for the quantitative evaluate the influence of VOCs towards O3" |
Keywords: | "Air Pollutants/*analysis China Chromatography, Gas/methods Cities *Environmental Monitoring Ozone/*analysis Volatile Organic Compounds/*analysis;" |
Notes: | "MedlineCui, Hu-Xiong Wu, Ya-Ming Gao, Song Duan, Yu-Sen Wang, Dong-Fang Zhang, Yi-Hua Fu, Qing-Yan chi Research Support, Non-U.S. Gov't China 2012/04/04 Huan Jing Ke Xue. 2011 Dec; 32(12):3537-42" |