Omelnyk O. The characteristic X-ray emission induced by ions, X-rays, rays beams and determination of elements III group in materials of nuclear power

The dissertation is dedicated to the investigations and search of new correlations in physical processes of excitation a characteristic X-rays and its interaction with substance and the developing of installations and methods for analysis of the content of elements III group in materials of nuclear power on base the experimental data obtained. The next analytical techniques were used: two variants of method a proton induced X-ray emission - in the vacuum chamber and on the external proton beam; method of X-ray fluorescence excitation with radioactive source and vacuum tube. On the basis of the developed empirical model the analytical expression was obtained for description of the observational quantities of K-shell ionization cross-sections for elements with atomic number from 57 to 71 by protons with energy of 1-3 MeV. The analytical procedures and installations were developed and the next problems were resolved: content Sc, Y, Pr in the microalloyed samples of nickel and chromium-nickel steels was studied; diffusion constant of Sc in Ni was evaluated; allocation of Y and Zr in samples of dispersion-strengthened by oxides steel and allocation of Gd in samples of steel obtained by centrifugal molding were studied, content Gd in the uranium-gadolinium nuclear fuel was measured. The method for simultaneous determination of concentration of burnable poison gadolinium and a thickness of fuel cladding was developed.