Transformations on the Alkali-Halide Crystals Surface by the High-Energy Irradiation and Cold Air Plasma Influence

摘要

The alkali-halide crystals exposed to high-energy radiation such as X-ray, UV-radiation, #gamma#-radiation and cold air plasma result in complex interaction on the solid-gaseous interface. This interaction results in a lamina being formed on the crystal surface. The lamina usually includes such compounds as MeNO_3, MeNO_2, MeXO_3, MeXO_4, where Me is the alkali crystal, X is the halide. It has been set up by the electronic microscopy and X-ray diffraction analysis, that the compounds formed crystallize into islets at the initial steps. The islets will later enlarge and interflow into a single lamina. The phase composition in the lamina is related to the type and portion of irradiation, temperature, chemical composition of the initial solid and gas phases, as well as to the quantity of the electric charges in the treated crystals. More recently, the influence of X-ray irradiation upon the alkali-haloid crystsls was studied. It has been set up by the methods of electronic microscopy and X-ray diffraction analysis that the radiochemical transformations result basically in the crystal nitrate being formed on the initial crystals surace. The crystal nitrate presents as a surface lamina.