The three-body model a + n + p for 6Li is applied as a probe with elastic scattering of a -particles. Elastic scattering is described within the optical model framework, while the rising of the cross section at the backward scattering angles is treated by means of an approximation of the np transfer mechanism. Both parts of the optical potential are obtained by fitting the depths of the same folding potentials to experimental data. The folding potential, in turn, is based on the three body-wave function of 6Li. Spectroscopic amplitudes for the np cluster are extracted in calculations based on the CRC method. One-step and two-step transfer mechanisms are taken into account for the np transfer mechanism. The calculation results indicate the dominance of the one-step mechanism over the two-step transfer mechanism of the np cluster.
Studies of the properties of nuclei remote from the "valley of nuclear stability" make it possible to predict the properties of new nuclides based on systematic accumulations of data on the structure of nuclear matter. New phenomena in the behavior of nuclear matter are also being discovered. Such cores are called "exotic". The production of exotic nuclei is a multi-stage process, during which various approaches of theoretical and experimental physics are applied. One of the ways to obtain nuclei are fragmentation reactions of relatively light nuclei with high energy (more than 100 MeV), as a result of which exotic nuclei with different A and Z can be obtained. In this article, a study of the applicability of the high-energy approximation (HEA) in modeling such direct nuclear reactions was conducted and the results of comparing this approach with the exact solution of the Schrodinger equation using the example of a rectangular potential barrier and a Gaussian potential barrier are presented. Comparison of different approaches provides an understanding of the limitations of their applicability for further study of the properties of nuclei in interaction with each other and for solving the Schrodinger equation with similar potentials considered.
The main purpose is determine and evaluate uranium concentration in urine of the inhabitants of nearby settlement of uranium mining sites and workers of uranium processing sites. As uranium enterprises working in Stepnogorsk of Akmola Region and its exploitation could be a risk of radiation exposure for the workers as well as for the local population, monitoring of biosamples could allow information about the exposure to uranium for the workers and inhabitants. Workers and inhabitants of male genders were asked to collect 24 h-urine samples. The concentration of uranium in urine was measured in mass spectrometry (ICP-MS). Uranium concentration in urine samples from workers values ranged from 0.05 to 12.5 μgL−1 , for Akmola region inhabitants values ranged from 0.10 to 0.60 μgL−1 . The results of concentrations of uranium in the urine of inhabitants living near SMCC were comparable to values reported in other studies. The concentration of uranium in the urine of the workers had slightly elevated values, comparable to the conditional norm of 0.9 μg/L.
We present the first report on the structural effects induced by swift xenon ions in nanocrystalline pyrochlore Y2Ti2O7 (outside the metal matrix) studied using high resolution transmission electron microscopy. Latent amorphous tracks were observed in the range of electronic stopping powers 4.8–23.2 keV/nm. Obtained results enabled estimation of the threshold energy loss values for formation of continuous and not continuous (surface) tracks at ≈ 8 keV/nm and 3.5 keV/nm, respectively.
The nature of intrinsic emission and the creation of electron-hole trapping centers in irradiated with ultraviolet and X-rays at 15 K and 300 K was investigated in Li2SO4 by methods of spectroscopy. It is shown that in activated Li2SO4 with an energy of 6 ÷ 12.4 eV, emission appears in a wide spectral range to excite rare earth ions that are used as UV sources. These same photons create electron-hole trapping centers as well.
The radiative relaxation of exciton-like formations in KCl-Na single crystal has been studied by experimental methods of luminescent spectroscopy. The amplifying effect of the radiation intensity with a maximum at 2.8 eV up to 500 times as compared to pure KCl has been detected in KCl-Na. The luminescence efficiency of an exciton-like formation increases with rise in: sodium ions concentration ( 10 ÷ 1000 ppm), thermal exposure ( 500◦C ÷ 600◦C ) and the degree of uniaxial deformation along <100> and <110> crystallographic directions. Previously, such a scale of the luminescence enhancement effect has not been registered in KCl matrix at room temperature. At high sodium concentrations (1000 ppm) in KCl-Na crystals, the additional intense emission with a maximum at 3.1 eV has also been revealed, which is typical for pair sodium ions. It is interpreted that the exciton-like formation in the sodium field with the maximum quantum yield of luminescence is formed by recombination assembly of electron-hole pairs due to the mobility of unrelaxed holes.
This work are presented the calculation results of thermodynamic parameters of the reaction of magnesium fluoride decomposition by ionized water vapor with the formation of solid magnesium oxide and gaseous hydrogen fluoride at atmospheric pressure in the temperature range from room temperature to 2800◦C . The calculation of the thermodynamic parameters was carried out with the Reaction Equations software module of scientific programs HSCChemistry package. Thermodynamic analysis of magnesium fluoride MgF2 was carried out on a thermogravimetric analyzer TGA/DSC2. The thermodynamic parameters results are in good agreement with the results of thermogravimetric analysis. There were determined the optimum conditions for plasma-chemical processing of magnesium fluoride.
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