针对灰霾天气条件下主要污染物粒子, PM2.5主要组分, 以硫酸铵和碳质气溶胶粒子为典型粒子, 运用T矩阵方法研究了这两种粒子不同形态的散射特性, 包含椭球体(长短轴比a/b=1/2, 1/3, 2/1), 圆柱体(直径与长度比D/L=1/2, 1/3, 1/1, 2/1)及切比雪夫形(多项式n=2, 形变参数?孜=-0.1, 0.1), 两种粒子在不同形态下所对应的散射、消光及吸收效率因子随尺度参数的变化规律。结果表明, 硫酸铵非球形粒子在尺度参数小于1时, 不同形状粒子效率因子差异很小, 从尺度参数大于1开始, 散射、消光效率因子随尺度参数先增加后震荡减小, 粒子吸收非常弱; 而碳质气溶胶粒子在尺度参数小于2时, 不同形状粒子效率因子差异很小, 尺度参数大于2开始, 各效率因子随尺度参数先增加然后缓慢减小, 并且对光场具有较强的吸收作用。该研究结果可用于大气灰霾粒子探测分析, 发展大气环境污染防护科技。

Scattering characteristics of atmospheric haze particles, main ingredients particles of PM2.5 were studied, ammonium sulfate and carbonaceous aerosol particles were taken as typical example. By the T matrix algorithm, the non-spherical particles of ammonium sulfate and carbonaceous aerosol particles were analyzed, including the ellipsoid particles(major to minor axis ratio, a/b=1/2,1/3,2/1), cylindrical particles(diameter to length ratio, D/L=1/2,1/3,1/1,2/1) and chebyshev particles(polynomial n=2,deformation parameter ?孜=-0.1,0.1). Corresponding scattering, absorption and extinction efficiency factor changing with the shape and the size parameter were given. Study results show that, for ammonium sulfate particles, if size parameter was less than 1, efficiency factor tendencies of different shape particles were similar, if size parameter was greater than 1, scattering and extinction efficiency factor increased with the size parameter and then decreased with oscillation, and absorption of ammonium sulfate particles were weak. For carbonaceous aerosol particles, if size parameter was less than 2, efficiency factor tendencies of different shape particles were similar, if size parameter was greater than 2, efficiency factor increased with the size parameter and soon decreased slowly and smoothly, and carbonaceous aerosol particles had strong absorption of light. The analyzing results can be used for optical monitoring and detection of haze particle, improve the ability of science and technology supported environmental pollution prevention.