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本文简要介绍了核素６０Ｃｏ、８５Ｓｒ和１３７Ｃｓ在非饱和黄土介质中迁移的环境模拟试验结果。文中简述了试验的模拟装置和方法；给出了主要的试验结果，包括２号土柱与４号土柱黄土中８５Ｓｒ比活度垂直分布的直接测量结果和４号柱黄土中６０Ｃｏ和１３７Ｃｓ比活度垂直分布的取样测量结果。对模拟试验测量数据进行了拟合与分析，得到了８５Ｓｒ比活度垂直分布的质心坐标ｚ０（ｔ）随试验时间ｔ的变化关系；给出了２号和４号土柱中８５Ｓｒ比活度垂直分布方差σ２（ｔ）（ｃｍ２）随ｔ（ｄ）变化的拟合公式，其分别为幂函数σ２（ｔ）＝０．２１８ｔ０．７１６和σ２（ｔ）＝０．０３３４ｔ０．９６２；根据ｔ＝３６５ｄ时４号土柱的取样测量结果，用二次矩方法计算了６０Ｃｏ和１３７Ｃｓ的比活度分布方差，其值均为σ２（ｔ＝３６５ｄ）＝０．２０ｃｍ２；还估算了土柱中的水流速度ｕ、８５Ｓｒ的平均迁移速度ｖ和延迟系数Ｒｄ。
In this paper, the environmental simulation results of migration of radionuclides 60Co, 85Sr and 137Cs in unsaturated loess media are briefly introduced. The main experimental results are given, including the direct measurement results of the vertical distribution of 85Sr specific activity in No. 2 soil column and No. 4 soil column loess, and the distributions of 60Co and 137Cs in No. 4 column loess Sampling measurements of vertical distribution of specific activity. The simulated test data were fitted and analyzed, and the vertical distribution of centroid coordinates z0 (t) of 85Sr specific activity was obtained. The variation of 85Sr specific activity in soil columns No.2 and No.4 The fitting formula of variation of vertical distribution variance σ2 (t) (cm2) with t (d) is the power function σ2 (t) = 0.218t0.716 and σ2 (t) = 0.0334t0.962, respectively; = 365d when the measurement result of the sample No. 4 of the soil column, with the second moment method to calculate the variance of the distribution of specific activity 60Co and 137Cs, which values are σ2 (t = 365d) = 0.20cm2; also estimated soil column Of the water flow rate u, 85Sr the average migration speed v and the delay coefficient Rd.