引用本文:
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 326次   下载 210 本文二维码信息
码上扫一扫!
分享到: 微信 更多
光腔衰荡光谱法测量大气中的NO3和N2O5
吴 昊1, 陈 剑2, 刘安雯2, 胡水明*1,2, 张劲松3
1.中国科学技术大学合肥微尺度物质科学国家研究中心,合肥 230026;2.中国科学技术大学化学与材料科学学院,合肥 230026;3.美国加州大学河滨分校化学系和大气污染研究中心,河滨 92521
摘要:
本文应用基于二极管激光器的双路光腔衰荡光谱技术,分别对大气中NO3和N2O5浓度进行监测. 通过使用实验室标准样校正有效吸收腔长比RL和系统的总损耗系数?,并获得了NO3有效吸收截面. 该装置在时间分辨率为1 s时,对NO3的测量灵敏度达到1.1 pptv,N2O5被在线转换成NO3,从而被另一路光腔衰荡光谱装置探测. 利用该装置,对合肥市区冬季夜间大气中的NO3,N2O5浓度进行了实时监测. 通过对比一次大气快速清洁过程中氮氧化物、臭氧、PM2.5等组分的浓度变化,讨论了大气环境下可能影响NO3及N2O5浓度的因素.
关键词:  光腔衰荡光谱,NO3自由基,N2O5,大气监测
DOI:10.1063/1674-0068/cjcp1910173
分类号:
基金项目:
Cavity Ring-Down Spectroscopy Measurements of Ambient NO3 and N2O5
Hao Wu1, Jian Chen2, An-wen Liu2, Shui-ming Hu*1,2, Jing-song Zhang3
1.Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China;2.Department of Chemical Physics, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei 230026, China;3.Department of Chemistry and Air Pollution Research Center, University of California, Riverside California 92521, USA
Abstract:
NO3 and N2O5 are important participants in nocturnal atmospheric chemical processes, and their concentrations are of great significance in the study of the mechanism of nocturnal atmospheric chemical reactions. A two-channel diode laser based cavity ring-down spectroscopy (CRDS) instrument was developed to monitor the concentrations of NO3 and N2O5 in the atmosphere. The effective absorption length ratio and the total loss coefficient of the instrument were calibrated using laboratory standard samples. The effective absorption cross section of NO3 at 662 nm was derived. A detection sensitivity of 1.1 pptv NO3 in air was obtained at a time resolution of 1 s. N2O5 was converted to NO3 and detected online in the second CRDS channel. The instrument was used to monitor the concentrations of NO3 and N2O5 in the atmosphere of winter in Hefei in real time. By comparing the concentration changes of pollutants such as nitrogen oxides, ozone, PM2.5 in a rapid air cleaning process, the factors affecting the concentrations of NO3 and N2O5 in the atmosphere were discussed.
Key words:  Cavity ring-down spectroscopy, Nitrate radical, Dinitrogen pentoxide, Field measurement
附件