对计算土壤和岩石中氡浓度及其表面析出率表面边界条件的讨论

本文对求解土壤或岩石中氡浓度及其表面析出率的边界条件进行了探讨。以空气中无穷远处氡浓度为零（空气中无氡源）的自然边界条件代替空气与土壤或岩石交界面氡浓度为零的边界条件，给出了土壤和岩石中氡浓度及其表面析出率的具体表达式。与前人研究结果比较，该式中增加了一项，表面氡析出率缩小了一个倍数。通过对土壤、岩石的具体计算．表明两种边界条件的计算结果有相当的偏差。同时，文中还讨论了在两类边界条件下对流对土壤或岩石中氡浓度及其表面析出率计算的影响。

DISCUSSION ON BOUNDARY CONDITIONS FOR CALCULATING RADON CONCENTRATIONS AND SURFACE EXHALATION RATES IN SOIL AND ROCK

In this paper, instead of the boundary condition that radon concentration at the interfaceof air and medium is equal to zero, the natural boundary condition that radon concentrationin air is equal to zero at infinite point (i. e., no radon source in air) is applied to derive theexpressions of radon concentration and surface exhalation rate in soil and rock. As comparedwith the results from references, an item is added for the radon concentration, then the exhalation rate is decreased by 1-2 times. The calculation shows that there is a great deviationbetween results obtained by two kinds of calculation of boundary conditions. Moreover, theinfluence of convection current on the calculation of radon concentration is discussed for difference conditions.