【摘要】 在天津地区 2 0m ,4 0m和 6 0m三个不同高度同步采集冬季大气颗粒物中PM10 样品 ,测定了 16种多环芳烃 (PAHs )含量 不同高度PM10 中PAHs的含量均表现出大气颗粒物中随高度先增后降的趋势 ,颗粒物质量中值直径 (MMD )也呈现类似规律 ,但PAHs总浓度的MMD则呈向上递增的趋势 不同高度PAHs的粒径分布差别不大 ,高分子量的PAHs主要集中在空气动力学直径Dp<2 μm的细颗粒上 ,而Dp>2 μm的粗颗粒上低分子量的PAHs相对较多更多还原

【Abstract】 Vertical and size distributions of 16 polycyclic aromatic hydrocarbons (PAHs) have been measured twice in ambient aerosols collected at heights of 20m, 40m, and 60m in Tianjin urban area. Vertical distributions of PM 10 and 16 PAHs show a peak at 40m. The same trend was observed for the mass medium diameter (MMD) of PM 10. The MMD of ΣPAH(sum of 16 PAHs), however, monotonically increase with height. Size distributions of PAHs in the aerosols were almost the same at various heights. PAHs with high molecular weight were mainly distributed in the fine particles (aerodynamic diameter <2μm). The fractions of low molecular weight PAHs were mainly associated with coarse particles (aerodynamic diameter >2μm).更多还原