某戈壁区域地表气溶胶粒度特性研究

Study on Particle Size Characteristics of Aerosols in a Gobi Region

为了对进入某戈壁区域的人员内照射剂量计算提供充足有效的数据,深入研究该地区的气溶胶粒度特性具有重要意义。使用大流量采样器采集粒径<10μm的气溶胶,再由γ谱仪测量核素活度;使用电子低压碰撞器(ELPI)测量气溶胶粒径分布。结果表明:扰动状态下的再悬浮系数比自然状态下的高约3个数量级;自然状态下气溶胶数量中位直径(CMAD)介于0.066～0.158μm之间,质量中位直径(MMAD)介于0.315～10.846μm之间;扰动状态下,气溶胶数量中位直径介于0.051～0.089μm之间,质量中位直径介于15.730～17.422μm之间。

In order to provide sufficient and effective data for the calculation of the radiation dose in the area of a Gobi re-gion, it is very important to study the aerosol particle size characteristics in depth. The aerosol with particle size less than10 μm is collected using a large flow sampler and the nuclide activity is measured by a gamma spectrometer. The aerosol particle size distribution is measured by an electronic low voltage collider(ELPI). The results show that the recalculation coef-ficient in the disturbance state is about 3 orders of magnitude higher than that in the natural state. In the natural state, the me-dian diameter(CMAD) of aerosol is between 0.066～0.158 μm and the mass median diameter(MMAD) is between 0.315～10.846 μm. In the disturbance state, the median diameter of aerosol is between 0.051～0.089 μm and the mass median diameter is between 15.730～17.422 μm.