Characteristics of volatile organic compounds,NO2,and effects on ozone formation at a site with high ozone level in Chengdu

论文摘要

Chengdu is a megacity in the southwest of China with high ozone（O3） mixing ratio.Observation of volatile organic compounds（VOCs）, NO2 and O3 with high temporal resolution was conducted in Chengdu to investigate the chemical processes and causes of high O3 levels. The hourly mixing ratios of VOCs, NO2, and O3 were monitored by an online system from 28 August to 7 October, 2016. According to meteorological conditions,Chengdu, with relative warm weather and low wind speed, is favorable to O3 formation.Part of the O3 in Chengdu may be transported from the downtown area. In O3 episodes,the average mixing ratios of NO2 and O3 were 20.20 ppbv and 47.95 ppbv, respectively. In non-O3 episodes, the average mixing ratios of NO2 and O3 were 16.38 ppbv and 35.15 ppbv,respectively. The average mixing ratio of total VOCs（TVOCs） was 40.29 ppbv in non-O3 episodes, which was lower than that in O3 episodes（53.19 ppbv）. Alkenes comprised51.7% of the total O3 formation potential（OFP） in Chengdu, followed by aromatics which accounted for 24.2%. Ethylene, trans-pentene, propene, and BTEX（benzene, ethylbenzene,toluene, m/p-xylene, o-xylene） were also major contributors to the OFP in Chengdu. In O3 episodes, intensive secondary formations were observed during the campaign. Oxygenated VOCs（OVOCs）, such as acetone, Methylethylketone（MEK）, and Methylvinylketone（MVK）were abundant. Isoprene rapidly converted to MVK and Methacrolein（MACR） during O3 episodes. Acetone was mainly the oxidant of C3-C5 hydrocarbons.

论文目录

• Introduction
• 1. Methods
•   1.1. Sampling site
•   1.2. Instrumentation and data treatment
• 2. Results and discussion
•   2.1. Meteorological conditions
•   2.2. Levels and speciation of VOCs
•   2.3. Behaviors of critical VOC species in O3episodes and non-O3episodes
•   2.4. Relationship of O3to NMHC and NO2
•   2.5. OFP contributions
• 3. Conclusions

文章来源

类型: 期刊论文

作者: Yuanyuan Deng,Jing Li,Yaqi Li,Rongrong Wu,Shaodong Xie

来源: Journal of Environmental Sciences 2019年01期

年度: 2019

分类: 工程科技Ⅰ辑

专业: 环境科学与资源利用

单位: College of Environmental Sciences and Engineering, State Key Joint Laboratory of Environmental Simulation and Pollution Control,Peking University

基金: National Natural Science Foundation of China (Grant no.91544106),financial support from the Environmental Science Research Institute of Chengdu city for Research of Ozone Formation and Controlling Measures in Chendgu

分类号: X515

页码: 334-345

总页数: 12

文件大小: 1423K

下载量: 102