摘要
1999年 2月、3月、1 1月和 1 2月,在北京北三环外的 3 2 5m气象塔院内进行了大气颗粒物采样,获得 2 4组 1 92个分级样品.样品用质子激发X荧光(PIXE)方法进行了分析,得到大气颗粒物化学元素浓度及其谱分布.研究结果表明,北京大气颗粒物的化学组成和来源正在发生变化.由于采暖期间煤炭使用量的大量减少,大气中S,As,Se,K的浓度大幅度降低,S和K比采暖前低 2 5 %;由于北京冬季采暖大量使用重油替代煤炭作为取暖燃料,大气中Cu的含量比采暖期前增加了 1倍.此外,由于无铅汽油的推广使用,目前北京大气颗粒物中的Pb含量已大幅度降低.由于采取了一系列污染控制措施。
In February, March,November and December 1999, atmospheric particle samples were collected with cascade sampler at northern suburb of Beijing. The elemental concentrations and elemental distribution of particles were obtained by PIXE method. From the observation, the elemental concentrations, elemental distribution and their changes are analyzed. It shows that the concentrations of S, K, As, Se during heating period are lower than that before heating period because of decrease of coal combustion. The concentration of Cu doubles due to the using heavy oil instead of coal for heating in winter. Concentration of Pb in atmospheric particles has decreased dramatically due to using non leaded gasoline. It shows that the chemical composition and source of atmospheric particles are changing greatly. The pollution condition of atmospheric particles in Beijing has been improved obviously because of air pollution control by local government.
出处
《中国科学院研究生院学报》
CAS
CSCD
2002年第1期75-81,共7页
Journal of the Graduate School of the Chinese Academy of Sciences
基金
国家重点基础研究发展规划资助项目(G19990 4340 0 )
中国科学院KZCX2 2 0 4项目
中国科学院 引进国外杰出人才 "计划项目支持
关键词
大气颗粒物
PIXE
元素成分
采暖期
atmospheric particles, PIXE, elemental concentration, heating period
