Water-sensitive positron trapping modes in nanoporous magnesium aluminate ceramics

Abstract

The water-sensitive positron trapping modes in nanoporous MgAl 2O4 ceramics with a spinel structure are studied. It is shown that water-sorption processes in magnesium aluminate ceramics leads to corresponding increase in positron trapping rates of extended defects located near intergranual boundaries. This catalytic affect has reversible nature, being strongly dependent on sorption water fluxes in ceramics. The fixation of all water-dependent positron trapping inputs allow to refine the most significant changes in positron trapping rate of extended defects. © 2007 IOP Publishing Ltd.