Effect of particle size of nitrate and oxides as a heterophase impurity on the radiation decomposition of pure and Ba2+ doped KNO3 crystals

Study of the radiation decomposition of (i) pure KN03 in the presence of varying amounts of Pb0 or Al203 and (ii) KN03 doped with varying amounts of Ba(N03)2 in the presence of these oxides showed that the yield of nitrite depends on the particle size of the salt. Furthermore the G(N02-) values were found to change with the mole percent of Pb0 or Al203 in the admixture. The presence of Pb0 gave an enhancement in the decomposition yield while that of Al203 retarded the rate of formation of nitrite during radiolysis. These observations are attributed to the availability of larger surface areas for effective energy transfer at the interface between intimately close particles of the components of the mixture. (author)