Polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5 within boundary layer: Cloud/fog and regional transport.
Polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5 within boundary layer: Cloud/fog and regional transport.
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DOI：
10.1016/j.scitotenv.2018.01.014
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发表时间：
2018-06
期刊：
影响因子：
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通讯作者：
Min-min Yang;Yan Wang;Hong-li Li;Tao Li;Xiaoling Nie;Fangfang Cao;Fengchun Yang;Zhe Wang
中科院分区：
文献类型：
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作者：
Min-min Yang;Yan Wang;Hong-li Li;Tao Li;Xiaoling Nie;Fangfang Cao;Fengchun Yang;Zhe Wang
通过对庐山（海拔1165 m）PM2.5中多环芳烃（PAHs）的分析，研究了PM2.5中PAHs的分布特征及云雾对PAHs的影响。其主要目的是量化的主要排放源的多环芳烃和估计区域内的边界层传输的影响。庐山位于边界层和对流层之间，是研究大气输送的理想场所。采用GC-MS分析了PM2. 5中多环芳烃的浓度。结果表明，庐山大气中PAHs的体积浓度为6.98 ng/m3，变化范围为1.47 ~ 25.17 ng/m3，质量浓度为160.24 μg/g，变化范围为63.86 ~ 427.97 μg/g。主要化合物为BbF、Pyr和BP。从芳香环的分布来看，4-6环多环芳烃占主导地位，表明颗粒物中高环多环芳烃的贡献大于低环多环芳烃。由于庐山云雾天气频繁，在云雾天气前后测定了PM2. 5中多环芳烃的浓度。结果表明，云/雾和降雨条件导致较低的多环芳烃水平。采用回归分析的方法研究了多环芳烃的分布与温度、湿度和风等气象条件的关系。结果表明，温度和风速与多环芳烃浓度呈负相关，而湿度与多环芳烃浓度的相关性不显著。此外，后向轨迹和主成分分析结合DR（诊断比分析），以确定区域传输和主要排放源的影响。结果表明，庐山PM2.5中的多环芳烃主要受区域交通的影响，移动的汽车和钢铁工业是主要排放源，其排放量占庐山地区多环芳烃总量的56.0%。此外，反向轨迹显示，占主导地位的气团来自西北约占三分之一的总PAHs。
A study of PM2.5-associated PAHs analysis at Mount Lushan (1165 m) was conducted to investigate the distributions of PAHs in PM2.5and influences of cloud/fog. The main purpose was to quantify the main emission sources of PAHs and estimate regional transport effects within the boundary layer. Mount Lushan is located between the boundary layer and troposphere, which is an ideal site for atmosphere transport investigation. The concentrations of PAHs in PM2.5were analyzed with GC–MS. The results showed that the volume concentration was 6.98 ng/m3with a range from 1.47 to 25.17 ng/m3and PAHs mass were 160.24 μg/g (from 63.86 to 427.97 μg/g) during the sampling time at Mount Lushan. The dominant compounds are BbF, Pyr and BP. In terms of aromatic-ring PAHs distributions, 4–6-ring PAHs are predominant, indicating that the high-ring PAHs tend to contribute more than low-ring PAHs in particulates. Due to frequent cloud/fog days at Mount Lushan, PAHs concentrations in the PM2.5were determined before and after cloud/fog weather. The results demonstrated that the cloud/fog and rain conditions cause lower PAHs levels. Regression analysis was used for studying the relationship of PAHs distributions with meteorological conditions like temperature, humidity and wind. The results showed that the temperature and wind speed were inversely related with PAHs concentration but humidity had no significant relationship. Furthermore, backward trajectories and PCA combined with DR (diagnostic ratio analysis) were employed to identify the influences of regional transport and main emission sources. The results revealed that PAHs in PM2.5were mainly affected by regional transport with the main emissions by mobile vehicle and steel industry, which contributed about 56.0% to the total PAHs in the area of Mount Lushan. In addition, backward trajectories revealed that the dominant air masses were from the northwest accounting for about one third of total PAHs.