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Simultaneous study of magnetic and electrocatalytic properties of cobaltites under extreme conditions expands understanding of physical and chemical processes proceeding in them with the possibility of their further practical application. Therefore, La0.6Sr0.4CoO3 (LSCO) nanopowders have been synthesized at different annealing temperatures tann = 850, 875, 900 C, and their multifunctional properties have been studied comprehensively. As tann increases, the rhombohedral perovskite structure of the LSCO becomes more single-phase, whereas average particle size and dispersion grow. Co ions are in mixed valence states, including major Co3+ and Co4+ components. It has been found that the LSCO-900 shows two main Curie temperatures, TC1 and TC2, associated with a particle size distribution. As an external hydrostatic pressure P increases, average and increase from 253 and 175 K under ambient pressure to 268 and 180 K under P = 0.8 GPa, respectively. At the same time, the antiferromagnetic temperature TAFM and blocking temperature TB also increase from 145 and 169 K to 158 and 170 K, respectively. The increment of for the smaller and bigger particles is sufficiently high and equals 10 and 13 K/GPa, respectively. The magnetocaloric effect in the LSCO-900 nanopowder is relatively weak but with an extremely wide peak > 50 K that makes this composition interesting to be used as one of the components of the composite expanding its working temperature window. Moreover, all LSCO samples showed excellent electrocatalytic performance for the overall water splitting (OER) process (overpotentials only 265-285 mV at a current density of 10 mA/cm2) with minimal values for LSCO-900. Based on the XPS data, it was found that the formation of a dense amorphous layer on the surface of the particles ensures high stability as a catalyst (at least 24 h) during electrolysis in 1 M KOH electrolyte., Comment: 40 pages, 19 figures, 9 tables, 90 references, article

Goal. During the production of railway axles, the main target is to obtain a uniform metal structure with a grain size not larger than number 5 across the entire section of the produced axle. Moreover, in accordance with the demands of railway axle consumers, the differences in grain size numbers should not exceed 2. However, due to multi-stage processing and repeated heating of axle material, the fulfillment of aforesaid requirements is very difficult and the differences in grain size numbers are usually found as 4. Therefore, it is necessary to develop a special deformation regime for controlling the sizes and the uniformities of metal grains in the finished product. Methods. We employed experimental and theoretical investigations to reveal the microstructure refinement in the deformation zone of the produced railway axle. The experimental investigation was carried out under the production conditions, whereas the theoretical investigation was performed based on the theory of plasticity and finite element method. Results. Furthermore, the regularities of process parameters in the deformation zone were revealed; hence, a new deformation regime was developed, and consequently, the quality of the finished railway axle was improved. Scientific novelty. Rolling of solid railway axle required special de-formation regimes that differed from the deformation regimes for rolling of other types of products. Deformations in vertical and edging directions with edging reduction were less penetrative to the central zone of the billet as compared to surface layers, thus resulting in an increase in energy consumption and equipment load of the rolling mill. Rolling with edging reduction caused a worse de-formation at the central zone of the billet in the box caliber.Rolling without edging reduction caused large deformations in central layers of the billet and led to a significant improvement in the metal structure of the axle.

The paper contains a short description of the scientific papers of Professor Boris Ya. Sukharevsky on condensed matter physics. His basic scientific activity was related to following directions: structural vacancies concept; influence of point defects on statics and kinetics of phase transitions; DNA crystallization and low-dimensional systems properties; phase transitions in Jahn-Teller crystals; Thermophysics of superconductors e.a. The list of most essential papers of Prof. B.Ya. Sukharevsky is included., Comment: 16 pages, 53 references