Exploring the nitrous acid (HONO) formation mechanism in winter Beijing: direct emissions and heterogeneous production in urban and suburban areas
Exploring the nitrous acid (HONO) formation mechanism in winter Beijing: direct emissions and heterogeneous production in urban and suburban areas
复制标题
探讨北京冬季亚硝酸（HONO）形成机制：城乡直接排放与异质生产
DOI：
10.1039/c5fd00163c
复制
发表时间：
2016
影响因子：
3.4
通讯作者：
Ge Maofa
中科院分区：
文献类型：
--
作者：
Tong Shengrui;Hou Siqi;Zhang Ying;Chu Biwu;Liu Yongchun;He Hong;Zhao Pusheng;Ge Maofa
为研究亚硝酸的形成机理，于2015年12月12日至22日在北京市区和郊区进行了亚硝酸(HONO)的连续监测。这两个地点的测量活动都包括一个清洁-雾霾-清洁的转化过程。HONO浓度在两个地点显示出相似的变化，而城市地区的HONO浓度总是更高。此外，还研究了HONO与NOx、NO2、NO、PM2.5和相对湿度(RH)的相关性，探讨了HONO生成的可能途径，并计算了直接排放、多相反应和均相反应对HONO的贡献。这表明城市和郊区HONO的形成过程完全不同，受气象条件、PM2.5浓度、直接排放、均相反应和非均相反应的影响。PM2.5浓度和相对湿度对NO2转化效率有影响。NO2的非均相反应在郊区和清洁期更有效，而直接排放和均相反应在城市地区和污染期间贡献更大，当NOx和NO浓度较高时。
Continuous measurements of nitrous acid (HONO) were performed from December 12 to December 22, 2015 in both urban and suburban areas of Beijing to study the formation mechanism of HONO. The measurement campaign in both sites included a clean–haze–clean transformation process. HONO concentrations showed similar variations in the two sites, while they were always higher in the urban area. Moreover, correlations of HONO with NOx, NO2, NO, PM2.5 and relative humidity (RH) were studied to explore possible HONO formation pathways, and the contributions of direct emissions, heterogeneous reactions, and homogeneous reactions were also calculated. This showed that HONO in urban and suburban areas underwent totally different formation procedures, which were affected by meteorological conditions, PM2.5 concentrations, direct emissions, homogeneous reactions and heterogeneous reactions. PM2.5 concentrations and RH would influence the NO2 conversion efficiency. Heterogeneous reactions of NO2 were more efficient in suburban areas and in clean periods while direct emissions and homogeneous reactions contributed more in urban areas and in polluted periods when the concentrations of NOx and NO were at a high level.