摘要
在威海市两个采样点用苏码罐采集了全空气样品,利用三级冷阱预浓缩-GC/MS方法离线测定了空气样品中109种大气挥发性有机物(VOCs).使用基于观测的MCM机理大气化学模式(OBM-MCM)分析了大气臭氧生成对VOCs组分的敏感性及本地生成过程.结果表明:观测期间两个采样点的总挥发性有机物(TVOCs)平均浓度分别为27.84×10^-9和17.85×10^-9,对TVOCs贡献最大的均是烷烃.模拟分析表明,大气臭氧生成与前体物的控制关系存在空间差异性,在一个观测点受VOCs控制,而在另一个观测点受NOx和VOCs共同控制;模拟结果还表明,臭氧生成对活性烃类最为敏感,但是,含氧有机物、卤代烃和高碳烷烃对臭氧生成的影响和贡献也不可忽视;此外,计算了日平均臭氧净生成速率P(O3)net,分别为6.41×10^-9 h^-1和3.22×10^-9 h^-1,臭氧的本地生成过程扮演重要角色.
The mixing ratio of 109 volatile organic compounds were analyzed by GC/MS coupled with stainless steel canister sampling and a three-state preconcentration, and the sensitivity of ozone formation to VOCs and local formation process were analyzed using the observation-based MCM mechanism atmospheric chemistry model(OBM-MCM).The results showed that the average concentrations of total volatile organic compounds(TVOCs) at the two observation sites were 27.84×10^-9 and 17.85×10^-9, respectively, and the largest contribution to TVOCs was alkane. The simulation analysis showed that there was spatial difference between the sensitivity to the precursor of ozone, which was controlled by VOCs at one site and jointly controlled by NOx and VOCs at another site. The simulation results also showed that ozone formation was sensitive to active hydrocarbons, but the influence and contribution of oxygenated organic compounds, halogenated hydrocarbons and high carbon alkanes to ozone could not be ignored. In addition, the daily average net ozone generation rate P(O3)net at two sites was 6.41×10^-9 h^-1 and 3.22×10^-9 h^-1, respectively and the local ozone photochemical formation plays a key role in ozone concentration.
作者
马伟
王章玮
郭佳
张晓山
MA Wei;WANG Zhangwei;GUO Jia;ZHANG Xiaoshan(State Key Laboratory of Urban and Regional Ecology,Research Center for Eco Environmental Sciences,Chinese Academy of Sciences,Beijing 100085;University of Chinese Academy of Sciences,Beijing 100049)
出处
《环境科学学报》
CAS
CSCD
北大核心
2019年第11期3611-3617,共7页
Acta Scientiae Circumstantiae
基金
国家重点研发计划项目(No.2017YFC0210106,2016YFC0203200)
关键词
城市大气臭氧
挥发性有机物
相对反应增量活性
urban atmospheric ozone
volatile organic compounds
relative incremental reactivity
