Diffusion paths of cesium in water-saturated mortar
Diffusion paths of cesium in water-saturated mortar
复制标题
铯在水饱和砂浆中的扩散路径
DOI：
10.13182/nt97-a35364
复制
发表时间：
1997
影响因子：
1.5
通讯作者：
T. Arima
中科院分区：
文献类型：
--
作者：
K. Idemitsu;K. Kuwata;H. Furuya;Y. Inagaki;T. Arima
铯在水饱和砂浆中的扩散系数进行了测量，试图调查的迁移到砂浆的基质中的放射性核素。测量的示踪剂穿透剖面由两部分组成。在接近表面处有一个陡峭的斜坡，在砂浆内部有一个平缓的斜坡。许多研究人员已经报道了这种情况。这种配置文件成功地解释了考虑两个扩散路径的砂浆。一个扩散路径是通过几微米宽的裂缝，另一个是通过亚微米孔的完整砂浆网络。该模型得到了砂浆试件横截面放射自显影的支持。亚微米孔的体积占砂浆中总孔体积的约95%。铯的表观扩散系数的数量级为10 - 12 m2/s通过裂隙和10 - 14 m2/s通过孔隙网络。根据铯在裂隙中的表观扩散系数、裂隙孔径和裂隙间距估算出铯的有效扩散系数为10 - 13 m2/s。两条路径中的几何因子也通过使用自由离子的表观扩散率和扩散系数进行估计;裂缝和裂缝的几何因子估计为0.13，而自由离子的几何因子估计为0.13。01迫击炮矩阵。将该模型应用于其他研究者的数据，以估计有效扩散系数。该模型和估算方法与穿透扩散和渗透实验数据吻合较好。
Diffusivities of cesium in a water-saturated mortar were measured in an attempt to investigate the migration of radionuclides into the matrix of the mortar. The measured penetration profiles of the tracer were composed of two parts. There was a steep slope near the surface and a gradual slope in the mortar interior. This kind of profile has been reported by many researchers. This profile was successfully explained by considering two diffusion paths in the mortar. One diffusion path was through fissures with a width ofa few microns, and the other was through the intact mortar network of submicron pores. This model was supported by autoradiography of some cross sections of a mortar specimen. The volume of submicron pores was ∼ 95 % of the total pore volume in the mortar. The order-of-magnitude values for the apparent diffusivities for cesium were 10 -12 m 2 /s through the fissure and 10 -14 m 2 /s through the network of pores. The effective diffusion coefficient for cesium was estimated at ∼ 10 -13 m 2 /s by using the apparent diffusivities through the fissures, the aperture of the fissures, and the fissure interval. Geometric factors in the two paths were also estimated by using the apparent diffusivity and diffusion coefficients for free ions; they were estimated at ∼ 0.13 for fissures and ∼ 0. 01 for the mortar matrix. This model was applied to other researchers' data to estimate the effective diffusion coefficient. This model and estimation method show the consistency of the data from through-diffusion and penetration experiments.