SIMULTANEOUS DIFFUSION OF ISOTOPES FROM A RADIOACTIVE SERIES IN HOMOGENEOUS AND ISOTROPIC SOLIDS

The simultaneous diffusion of the members of a radioactive series is a nalyzed. The diffusion equations consider both the radioactive product ion and decay of each of the series members, including the effect of r adioactive recoil for alpha decays. Hydrodynamic coupling between the several isotope fluxes is not considered. The diffusion equations are solved in spherical coordinates for general initial and Dirichlet boun dary conditions. The obtained solutions are applied in an example of t he influence of diffusion and alpha recoil on the disequilibrium betwe en the ave initial isotopes of the uranium series. (C) 1998 Elsevier S cience Ltd. All rights reserved.