2008年北京采暖开始前后大气颗粒物化学成分及来源研究

Characteristics and sources of elements in atmospheric particles before and during the 2008 heating period in Beijing

为了系统反映北京采暖开始前后大气颗粒物的特征,于2008年10月底到12月初在北京北三环内城区使用分级式撞击采样仪进行了大气颗粒物采样,并用质子激发X射线荧光分析(PIXE)方法对其中16种化学元素浓度进行了分析.结果表明,采暖开始后16种元素总浓度较采暖期前增长3%,As、Cu在采暖期间的浓度增幅在30%以上,采暖开始后细粒子中Pb浓度增长为27%.富集因子分析结果表明,Cu、As、Pb等元素细粒子的富集因子比1999年同期有明显减小,说明北京近年来实行的环保措施较为有效.

In order to investigate the characteristics of atmospheric particles before and during the heating period in Beijing, aerosol samples were collected from October-December 2008. Mass concentrations of 16 elements were determined using Proton Induced X-ray Emission （PIXE）. The results showed that the total concentrations of all 16 elements increased by 3 percent in the heating period. However, several elements concentrations increased markedly. For example, concentrations of As and Cu increased by more than 30 percent, and the Pb concentration in fine particles increased by 27 percent. The enrichment factors of Cu, As, and Pb decreased greatly compared with those in 1999, which indicates that the particle pollution controls in Beijing are very effective.