摄取系数是表征大气非均相反应的重要物理化学参数,也是大气颗粒物表面摄取气体能力的重要量化指标,本文综述了摄取系数的主要概念、主要测定方法和影响因素,以NaCl与NO2非均相反应为例,讨论了用漫反射傅立叶转换红外原位反应器扩散实验方式测定反应摄取系数的方法和误差,分析了气体扩散深度与红外穿透厚度对测定结果的影响,并测定了初始反应摄取系数。
The uptake coefficient is an important physical and chemical parameter characterized the atmospheric heterogeneous reaction and a quantitative value determining to the uptake capacity of the trace gas on the atmospheric particles. The major concepts, measurement methods and influence factors of uptake coefficient were summarized in the paper. Taking the reaction of NO2with NaCl for example, the measurement methods and errors of the initial reactive uptake coefficient using the Diffuse Reflectance Infrared Fourier Transform Spectroscopy were discussed. The diffusing depth of the gaseous molecules and the penetrating depth of the in- frared beam were analyzed. In addition, the reactive uptake coefficient was determined.