2016年春节期间, 利用小流量采样器采集西安市大气颗粒物中PM2.5和PM10样品,有效样品30个,使用高效液相色谱仪(high performance liquid chromatography, HPLC)分析样品中16种多环芳烃(polycyclic aromatic hydrocarbons, PAHs)的质量浓度特征,及组分分布特征。 运用比值法和气象参数对PM2.5和PM10中PAHs来源进行解析。结果表明: 除夕后的颗粒物浓度(PM2.5平均质量浓度 为180 μg·m－3, PM10为286 μg·m－3)明显高于除夕前(PM2.5平均质量浓度为160 μg·m－3, PM10为88 μg·m－3); PAHs主要分布在PM2.5细颗粒中,约占70%以上; PM2.5和PM10中不同环数的芳烃分布主要以3环、4环 和5环为主;春节期间PAHs浓度持续居高, 主要源于冬季采暖煤的不完全燃烧以及汽油车和柴油车等交通污染排放, PAHs浓度的突然骤升主要来源于烟花爆竹的燃烧。

During the Spring Festival in 2016, PM2.5 and PM10 samples were collected from small particle sampler in Xi’an, China. The 30 effective samples were collected. The mass concentration characteristics and the distribution of the 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed by high performance liquid chromatography (HPLC). The PAHs sources in PM2.5 and PM10 were analyzed by the ratio method and meteorological parameters. The results showed that the PM2.5 mass concentration was 180 μg·m－3 and PM10 was 286 μg·m－3. The concentration of PM2.5 was significantly higher than that of New Year’s Eve (PM2.5 average concentration was 160 μg·m－3, PM10 was 88 μg·m－3). PAHs are mainly distributed in PM2.5 fine particles, accounting for more than 70%. The ring numbers of aromatic distribution in PM2.5 and PM10 are mainly 3, 4 and 5. During the period, the PAHs high concentration continued to rise, it was mainly due to the incomplete combustion of heating coal in winter and the traffic pollution caused by gasoline and diesel vehicles. The sudden rise of PAHs concentration mainly came from the burning of fireworks.