摘要
利用高分辨率场发射扫描电镜(FESEM)和图像分析技术研究了可吸入颗粒物(PM10)的单颗粒微观形貌类型及粒度分布特征.研究表明,煤矿区城市夏季可吸入颗粒物的微观形貌类型主要有矿物、烟尘集合体、球形颗粒及未知细颗粒.前3种颗粒(未知细颗粒不做统计)的数量百分比分别为41.2%,28.0%和30.8%,体积百分比分别为71.5%,22.3%和6.3%.颗粒物的数量-粒度呈单峰分布,主要分布在0.1～0.4μm范围内;体积-粒度分布则以大于1μm的矿物颗粒为主.夏季空气中球形颗粒和规则柱状矿物较多,说明矿区SO2,NOx含量较高而引起的大气二次化学反应严重.强风天气PM10的质量浓度明显降低,颗粒物数量主要分布在0.1～0.4μm粒径范围内.轻微浮尘天气PM10的质量浓度增大,颗粒物数量主要分布在0.1～0.4和1～2.5μm范围内,粒径大于1μm的矿物颗粒占总体积(质量)80%.
Microscopic characteristics and size distribution of different types of individual particulates were investigated by high resolution Field Emission Scanning Electron Microscopy（FESEM） and image analysis（IA）.Four microscopic types of particles in the PM10 were classified,including minerals,soot aggregates,spherical particles and unresolved particles.The minerals,soot aggregates and spherical particles accounted for approximately 41.2%,28.0% and 30.8% by number,and 71.5%,22.3% and 6.3% by volume,respectively.Number-size distribution of PM10 exhibited a unimodal pattern with the peak in 0.1-0.4 μm range,while the volume-size distribution of PM10 revealed that the mineral particles bigger than 1μm were dominant components.The abundant spherical particles and regular minerals present in the PM10 samples might suggest a serious chemical reaction in atmosphere during summer.When influenced by windy weather,the mass concentration of PM10 became lower,with particles mainly distributed in the size rang 0.1-0.4 μm by number.Under the floating dust weather,the mass concentration of PM10was high and most PM10 particles were distributed in the size range of 0.1-0.4 and 1-2.5 μm by number,the irregular minerals bigger than 1 μm could account for up to 80% in PM10 by volume.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2011年第2期292-297,共6页
Journal of China University of Mining & Technology
基金
教育部科技创新工程重大项目(705022)
高等学校博士学科点专项科研基金项目(20070290007)
