State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of Environmental Science and Engineering, North China Electric Power University, Beijing 102206, China.
Environ Pollut. 2018 Feb;233:662-669. doi: 10.1016/j.envpol.2017.10.103. Epub 2017 Nov 6.
In this study, concentrations of NO, SO, O and fine particles (PM) were measured at three monitoring stations in Beijing during 2015. For extreme haze episodes during 25 Nov. - 3 Dec. 2015, observation data confirmed that high concentrations of NO promoted the conversion of SO to sulfate. Annual data confirmed that this is an important mechanism for the occurrence of heavy haze during winter in Beijing. Furthermore, in situ perturbation experiments in a potential aerosol mass (PAM) reactor were carried out at Shengtaizhongxin (STZX) station during both clean and polluted days. The concentrations of SO, NH, NO and organic aerosol were positively related to the concentration of added NO. These results provide definitive evidence that NO can promote the conversion of SO to sulfate. At the same time, we found that NO can promote the formation of NH and organic compounds in the aerosols. Our results illustrate that strengthened controls of nitrogen oxides is a key step in reducing the fine particles level in China.
本研究在北京的三个监测站测量了 2015 年期间的 NO、SO、O 和细颗粒物（PM）浓度。对于 2015 年 11 月 25 日至 12 月 3 日期间的极端雾霾事件，观测数据证实，高浓度的 NO 促进了 SO 向硫酸盐的转化。年度数据证实，这是北京冬季发生严重雾霾的一个重要机制。此外，在盛泰中心（STZX）站的气溶胶质量（PAM）原位扰动实验在清洁和污染日进行。SO、NH、NO 和有机气溶胶的浓度与添加的 NO 浓度呈正相关。这些结果提供了明确的证据，表明 NO 可以促进 SO 向硫酸盐的转化。同时，我们发现 NO 可以促进气溶胶中 NH 和有机化合物的形成。我们的研究结果表明，加强对氮氧化物的控制是降低中国细颗粒物水平的关键步骤。
