  The problem of the diffusion evolution of a pore filled with molecular
hydrogen in a spherical granule in a hydrogen medium is solved. The initial
position of the pore is displaced relative to the center of the granule. A
nonlinear system of equations is obtained, which describes the behavior of the
size of the gas-filled pore, the amount of gas in it and its position relative
to the center of the bounded particle with time. Numerical calculations have
shown the existence of two stages of evolution. The first (fast) stage is
associated with the equalization of pressure in the pore with the external. The
second is the slow diffusion "healing" of the pore, when the amount of gas
adjusts to its size and the gas pressure is approximately equal to the
external.
