  In the present work, evolution of gas-filled pore inside spherical nanoshells
is considered. On the supposition that diffusion fluxes are quasistationary,
the nonlinear equation system is obtained analytically, that describes
completely the behaviour of gas-filled pore and matrix shell. Two limiting
cases are considered: the case when the pore is small as compared to the matrix
shell and the case of the pore close to the matrix shell boundary. The
characteristic regularities of pore behaviour are established.
