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After the ion implantation of silicon into sapphire followed by high-temperature annealing, silicon and aluminosilicate precipitates are observed in the surface region of sapphire. X-ray measurements with the mapping of reciprocal space show the presence of a compressive stress with a –0.12% strain in the normal direction, and a tensile stress with a 0.2% strain in the R plane in this region. This reduces the lattice mismatch between sapphire and Si(100) and, thus, can improve the crystal quality of epitaxial Si films grown on such modified sapphire substrates.

X-ray diffraction (XRD) analysis of composite samples based on ultra-high-molecular-weight polyethylene (UHMWPE) and polytetrafluoroethylene (PTFE), with a quasicrystalline filler Al–Cu–Fe, has been carried out. Samples with different filler concentrations were subjected to friction. A change in the degree of crystallinity of the polymer matrix is determined on the basis of the XRD data. Comparison of the diffraction patterns recorded at symmetric scan mode and in the grazing-incidence geometry showed a difference in the structures of the surface layers and sample bulk.

Samples of composites with polytetrafluoroethylene as the matrix and a powder of 0, 1, 2, 4, 8, 16, and 32 vol % Al–Cu–Fe quasi-crystal as the filler are prepared. Electron microscopy studies of the sample structure are carried out, the influence of the filler on the degree of crystallinity and the melting and destruction temperatures of the samples is investigated; mechanical tensile tests and tribological tests are performed. The composite samples with filler contents of 4, 8, 16, and 32 vol % show ultralow wear with the coefficient K < 5 × 10–7 mm3/N m. The highest wear resistance exceeding that of unfilled polytetrafluoroethylene by 2200–3100 times is recorded in composites with 16 vol % filler. An increase in the wear resistance is associated with formation on the friction surface of a thin crust containing quasi-crystal particles 0.2–0.3 μm in size, revealed by scanning electron microscopy in combination with energy dispersive analysis.

The use of high pressure (~8 GPa) in the formation of composite quasi-crystalline materials from powders made it possible to create practically poreless samples with a density close to the maximum known for this type of quasi-crystals. For samples with a nickel binder, sintered at a temperature of 550°C, a very low coefficient of friction was obtained, which retain its value during the testing.

In the article, the author discusses the importance of factor analysis methods, including the method of the main components, when studying multivariable information in the process of statistical analysis, with the aim of further modeling and predicting random processes. Key problems are described, when solving which they often turn to the method of the main components, as well as its algorithm, taking into account the fact that those interested in this article are familiar with the essence of statistical entimes. There is given a graphical representation of the author’s software, which reads the file specified by the user with a sample of data, made in the form of a table, which automatically prepares them for further analysis and search of the main components. The program functionality allows: to automatically calculate the mathematical expectation, variance of a multidimensional random variable; a covariance matrix for describing the shape of a random variable from which it is possible to obtain its dimensions by automatically finding eigenvectors and aigenpars; reduce the size of the sample; recover data for further hypothesis building and modeling. The algorithm of the principal component method is presented schematically.

We prepare composites in which ultrahigh-molecular-weight polyethylene (UHMWPE) is used as a matrix and quasicrystalline Al–Cu–Fe powder is used as a filler with concentrations of 1, 10, 30, and 50 vol %. The mechanical and tribological properties of the samples are measured, and electron microscopic studies of fractured regions are performed. It is shown that with increasing concentrations of the filler, the nature of fracturing of the samples changes. The minimum value of the friction coefficient is 0.07. It is assumed that the limiting factor in improving the tribological properties of UHMWPE–quasicrystal composites is the chipping of filler particles from the polymer matrix.

The thermal stability and structure of binary amorphous Zr100 − xBex alloys have been studied using differential scanning calorimetry and neutron diffraction over a wide concentration range (30 ≤ x ≤ 65). The amorphous alloys have been prepared by rapid quenching from melt. The studied amorphous system involves the composition range around the eutectic composition with boundary phases α-Zr and ZrBe2. It has been found that the crystallization of alloys with low beryllium contents (“hypoeutectic” alloys with x ≤ 40) proceeds in two stages. Neutron diffraction has demonstrated that, at the first stage, α-Zr crystallizes and the remaining amorphous phase is enriched to the eutectic composition; at the second stage, the alloy crystallizes in the α-Zr and ZrBe2 phases. At higher beryllium contents (“hypereutectic” alloys), one phase transition of the amorphous phase to a mixture of the α-Zr and ZrBe2 phases has been observed. The concentration dependences of the crystallization temperature and activation energy have been revealed.

Epitaxial films of CeO2 and Y2O3 on RABiTS metal tapes have been obtained by pulsed laser deposition. The dependence of the film crystal orientation on the temperature of synthesis has been studied. It is established that Y2O3 films grow with 100% (100) orientation, whereas a parasitic orientation is present in CeO2 films obtained in the entire range of growth temperatures. The texture sharpness in the substrate plane amounted to 8°. Electron-microscopic examination showed that an increase in the temperature of synthesis leads to the appearance of cracks on the surface of CeO2 films, while the surface of Y2O3 films remains continuous in the entire range of growth temperatures. Thus, Y2O3 films most fully obey the requirements to seed layers in (i) being epitaxial with 100% (100) crystal orientation, (ii) inheriting the substrate texture, and (iii) having a smooth crack-free surface.

The article describes the existing automation of petrol stations, it points to major drawbacks of existing systems. The authors offer an option of complex automation of petrol stations with introduction of the system at gas stations “Gazpromneft-center”.

The processes involved in refining steel at the Tagmet combine to remove corrosion-active nonmetallic inclusions (CANI) were analyzed using the program GIBBS®. The analysis was performed with the assumption that CANI are a special case of the oxide and sulfide inclusions normally seen in steels. Thus, it was proposed that the total number of all endogenic primary inclusions be reduced to a minimum and that their composition be optimized (that the inclusions be converted to the liquid state) in order to remove them from steel. It was shown that from 6 to 20% of all primary inclusions in steel are CANI, the exact percentage depending on the amount of alumo-calcium used in the treatment of the steel. It was also noted that the secondary oxidation of steel increases its volume content of primary inclusions by an order of magnitude. It was determined that the infiltration of oxygen into the treatment unit even at a rate of 0.3 kg/ton makes it impossible to obtain liquid primary inclusions. Modeling of the deoxidation of steel on a ladle-furnace unit at Tagmet made it possible to determine the optimum range of alumo-calcium consumption: 0.7–1 kg/ton (depending on the consumption of aluminum wire rod used for preliminary deoxidation). The formation of liquid primary inclusions — which includes CANI — is minimal in this case.

Цель: статья посвящена исследованию взаимосвязи кадровой стратегии и кадрового риска организации, влиянию кадрового риска на поведение человека. Обсуждение: анализ научных исследований показывает, что персонал организации, являясь ее важнейшим ресурсом, от качества, эффективности и рациональности использования которого зависят результаты деятельности и конкурентоспособность организации, одновременно является источником потерь, негативных воздействий, т. е. риска организации. Результаты: автором определена взаимосвязь кадрового риска и кадровой стратегии, сформулировано определение кадрового риска.