【摘要】 通过对兰州地区春季大气背景、浮尘、扬沙、沙尘暴天气的大气采样 ,得到了不同天气状况下大气气溶胶的浓度、PM1 0 的粒径分布及大气气溶胶的分布规律更多还原

【Abstract】 The influences of dust weather to the urban areas become more serious along with rapid increase of human activities and the intensification of land desertification. More than 10 dust storms occurred in north China in 2000, in which some dust storms occurred from the Hexi Corridor in Gansu Province affected many cities, such as Lanzhou and Beijing. Therefore, more and more scholars research dust weather, however, the research on the physical properties of aerosol is less. In this paper, the atmospheric samples including the atmospheric background, floating dusts, blowing sands and dust storms over Lanzhou region in spring are analyzed, the distribution of the mass concentration of atmospheric aerosol and the PM 10 particles is revealed. The results show that the dust weather occurs frequently over the Lanzhou region in spring, which is related to its geographical location and the meteorological conditions. The average mass concentrations, floating dust, blowing sands and dust storm are 0.486 8 mg/m 3, 1.466 4 mg/m 3, 2.130 5 mg/m 3 and 4.861 5 mg/m 3 respectively. The curves of atmospheric PM 10 granular distribution over the Lanzhou region are bimodal, trimodal and unimodal under floating dusts, blowing dusts and dust storms respectively. The proportions of the fine particles (<2.1μm) occupies 22.6%, 7.2%, 11.4% and 5.7% under the background weather, floating dusts, blowing dusts and dust storms respectively.更多还原