U, B, V, J, H, K photometry, polarimatry and spectroscopy of this peculiar object was made from August 1979 to December 1980. During 1979 it was at a phase of stable maximum brightness with variations of less than 0m.2 in magnitude and less than 0m.1 in colour. A change occurred at the beginning of 1980;the object was 0m.5 fainter in mid March and then faded rapidly. During the rapid fading the object became redder in U-B and B-V, and there was an intrinsic polarization of about 1%. At minimum in September 1980, B-V become even bluer than at maximum, while the 1.2-2μ flux was twice lower in October 1980 than in April 1979. At maximum the spectrum was of type F; the Ball lines indicating a luminosity higher than that of a normal supergiant.

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The microstructure and defect structure of low carbon steel after equal channel angular pressing and electroplastic rolling are considered. The influence of such treatment on the microhardness and impact strength of steel is established.

Classical T Tauri stars (CTTS) are at the early evolutionary stage when the processes of planet formation take place in the surrounding accretion disks. Most of the observed activity in CTTS is due to magnetospheric accretion and wind flows. Observations of the accreting gas flows and appearance of the line-dependent veiling of the photospheric spectrum in CTTS are considered. Evidence for the dusty wind causing the observed irregular variability of CTTS is presented. Photometric and spectroscopic monitoring of two CTTS, RY Tau and SU Aur, has been carried out atthe Crimean Astrophysical Observatory since 2013 aimed at studying the dynamics of accretion and wind flows on time scales from days to years. The observed variations in the dynamical parameters may be caused by changes in the accretion rate and in the global magnetic fields of CTTS.

The present work evaluates the possibility of using local minerals to create foundry alloys used in conditions of low temperature. The feasibility of using iron ores from the Kentik ore occurrence in the Verkhnevilyuysky district of the Republic of Sakha (Yakutia) for the manufacture of new cold-resistant and high-strength steels was analyzed. The ore contains oxides of alkaline earth metals: MgO, CaO, Sr0 and BaO, the total content of that is 1.6%, that contributes to the process of deoxygenation of the melt during its cooling, and the deoxygenation product in the form of oxides and other chemical compounds based on Ca, Sr and Ba floats into slag. The content of rare earth yttrium oxide is 0.0058%. Alloy is smelted from Kentik enriched ore, samples for static tensile and impact toughness tests were machined in order to study the mechanical properties. The results of chemical analysis showed that the total content of rare earth oxides Eu2O3, Tb4O7, Dy2O3 and Er2O3 was 0.062%. Such concentration of rare-earth metals promotes the increase of strength properties, as well as the operational characteristics of the material. The fracture surface of impact toughness sample is investigated. Analogues for comparing the strength and plastic properties were given. Technical instructions for obtaining an experimental samples of a cold-resistant medium-carbon alloy with increased strength for castings using a charge of naturally alloyed ferroalloy have been formulated.