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The electronic structure of the Co-doped indium tin oxide (ITO) diluted magnetic semiconductors (DMSs) were investigated theoretically from first principles, using the fully relativistic Dirac linear muffin-tin orbital band structure method. The X-ray absorption spectra (XAS) and X-ray magnetic circular dichroism (XMCD) spectra at the CoL3, InM2, SnM2, and OKedges were investigated theoretically from first principles. The origin of the XMCD spectra in these compounds was examined. The calculated results are compared with available experimental data.

The features of physical and mechanical properties of trees (Pinus sylvestris L. and Larix sibirica Ledeb.) are investigated in experimental mixed forest plantations created by sowing in the Irkutsk region. Saw cuts were taken in the butt part of model trees to determine the properties of wood. The studies were carried out according to generally accepted methods on certified equipment. According to the research it has been found that the average width of the annual layers of pine and larch is 3.54 mm and 2.93 mm, respectively. The average number of annual layers in one centimeter is from 3.42 to 3.61 mm, which is 3.24 and 3.73 times less than the average statistical data for these tree species. It allows us to conclude: the width of the annual layer is significantly greater in the first 20 years of forest plant life than in mature state. Strength indicators of the studied samples of pine and larch are lower by 12-30 % than standard ones. During mechanical tests, wood defects were found in the butt part of the larch, which led to the destruction of the specimens. These defects were dormant bud marks and bulging butt, which form at a fairly early age. Conditional density of pine and larch was determined using the Resistograph 4450 instrument for an additional qualitative assessment of wood. As a result of the studies, it can be concluded that strength characteristics of pine and larch in mixed plantations are quite high.

The expected thaw depth of the foundation soil is one of the parameters influencing the selection of technical solutions of road design in the permafrost area. The purpose of this research is a quantitative assessment of the degree of influence of air temperature on thaw depth of the road foundation soil in the permafrost area. A standard formula to calculate thaw depth of melting bodies of flat symmetry obtained through a solution of the one phase Stefan problem at boundary conditions of the first kind was used for the analysis. An algorithm using an analytical formula to assess the influence of the main initial parameters and accuracy of their determination on the resulting value, the thaw depth of the soil, is proposed. The results of the calculations are presented in a graphical form displaying the influence of average air temperature and the accuracy of its setting on the thaw depth of the road foundation soil. It was determined that the degree of change in thaw depth is non-linear and depends on both the average air temperature and on the accuracy with which it is set. For every average air temperature value there is a specific measure of required accuracy for thermal calculations so that the error of thaw depth determination does not exceed the permitted error. A 3D chart showing the expected percentage error in thaw depth forecasting depending on the average air temperature and the accuracy of its setting for an array of initial values was created.