摘要
Diffusion and sorption are important processes associated with radionuclides migration in crystalline rock. These processes are studied in the laboratory using borehole core samples. In this study, we obtained distribution coefficients (K (d)), apparent diffusion coefficients (D (a)) and retardation factor (R (f)) using batch and through-diffusion experiments. The and values obtained using the accumulative concentration method were lower than those derived in the batch experiments. These findings demonstrate that reliable R (f) and K (d) values of Tc-99 can be obtained using through-diffusion experiments with a non-reactive radiotracer, thereby bolstering confidence in the assessment of the long-term performance of disposal repositories.