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Study of the influence of the chemical composition and parameters of the complex treatment technology on characteristics of the microstructure, phase precipitates, the solid solution state, and mechanical properties was carried out for hot-rolled and cold-rolled Ti-stabilized IF steels. Cold-rolled products were annealed according to the regime of continuous hot-dip galvanizing units. The following methods of investigation were used: light, scanning and transmission electron microscopy, mechanical properties testing, thermodynamic analysis of phase stability conditions, and determination of the interstitial impurities content in a solid solution by internal friction. The possibility and conditions of a significant increase in ductility, formability of cold-rolled steels are established. They are obtained not by the traditional way consisting in reducing the content of interstitial elements and impurities, but by giving them a favorable form of existence. This is achieved by optimizing the chemical composition, first of all, the sulfur content, and parameters of thermo-deformation treatment of steel, which ensure complete carbon binding in Ti4C2S2 as a result of TiS transformation already at the hot-rolling stage. To reduce the yield and tensile strength, it is necessary to decrease the content of interstitial elements and to increase the temperature of recrystallization annealing of cold-rolled steel.

Thermodynamic analysis of phase transformations and reactions in Fe-Cr-C alloys is carried out with allowance made for all possible states, both stable and metastable, in the temperature range of metal dusting in aggressive carboniferous atmospheres. The results are compared with data on the corrosion resistance of chromium steel pipes under oil refining conditions. It is shown that, at high temperatures, one of the equilibrium phases in this system is the cementite solid solution (Fe1-y Cry)3C. Below ∼930 K, this phase becomes unstable to the decomposition into mixtures containing other carbides, but the tendency for chromium to stabilize cementite persists. The metal dusting mechanism changes in the composition range 0.03 ≤ y ≤ 0.055 (2.8–5.1 wt % Cr). This conclusion is supported by the results of tests on chromium steel (15Kh5M and 15Kh2M1) pipes under oil refining conditions, which indicate that the introduction of chromium into Fe alloys can only inhibit the degradation of Fe-Cr-C alloys under metal dusting conditions, without fully preventing it.

The clinical, ultrasonic duplex scanning and phlebographic (retrograde pelvis renoovaricography) examinations of 89 patients with chronic venous insufficiency of the pelvis were analyzed. Two forms of the clinical course of the disease were established: parietal and visceral. A detailed clinical, ultrasonic and phlebographic characteristics of these forms are described. The authors have developed two original methods of sclerotherapy: 1. varicose dilated superficial veins in the zones of atypical localization without using the elastic compression; 2. left ovarian vein with its following pharmacological spasm. The effectiveness of the sclerozing treatment was 86.6% with the first method and 100%--with the second method.

The representation of iron-based melts as associated liquids have been developed basing on the detail experimental investigation and analysis of available data on their thermodynamic properties and phase equilibria. It has allowed, for the first time, to interpret adequately the reactivity of the earth metals in the iron-based melts and to predict with high precision the reactions of metal refinement and non-metallic inclusions modifying in modern ladle metallurgy.