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The research paper examines the results of applying the proposed method of the laser processing of the composite slurry coating on the steel samples` surface such as 12Kh2N4A-Sh. An increase in the elastic-strength and tribological characteristics` surface occurs as a result of the imposition of several physicochemical processes in the laser-impact zone on the applied composite slurry coating with an epoxy element as the base material with the laser thermal hardening, the diffusion influence on the atomic boron along grain boundaries, carbonization and the formation of a modified surface layer. The conducted research shows the gradient structure of the surface layers. The coating composition varies in the studied samples, however, for all experimental samples, the elastic-strength and tribological characteristics are higher than the corresponding characteristics of the standard steel sample as 12Kh2N4A-Sh, which has undergone the cementation process. The calculated values of the resistance indicators of the elastic and plastic deformation are confirmed by the conducted tribological tests. It is given the higher efficiency of the laser processing method of the slurry coating and it is concluded the prospects of the proposed method.

The ultra-high-molecular-weight polyethylene reactor powders are widely used for the actively developing solvent-free method for producing high-strength high-modulus PE filaments, which includes the compaction and sintering of a powder followed by orientational hardening. To find an appropriate regime of the technological process, it is important to know how the nanostructure changes when transforming from a powder to a precursor for hardening. Nanocrystalline lamellae are characteristics of the powder structure. For the first time, the DSC technique was used to follow changes in the thickness distribution of lamellae in ultra-high-molecular-weight polyethylene reactor powder on its way to a precursor for orientation hardening. It was found that the percentage of thick (>15 nm) and thin (10 nm) lamellae in compacted samples and those sintered at temperatures lower than the melting temperature of PE (140°C) remains nearly the same. However, significant changes in the content of lamellae of different thicknesses were observed in the samples sintered at 145°C with subsequent cooling under different conditions. The influence of the lamellae thickness distribution in precursors on the mechanical characteristics of oriented filaments was discussed.

A comparative study of molecular dynamics in near-surface nanolayers and in a bulk of polyethylene is presented. Molecular mobility in near-surface nanolayers of polyethylene reactor powders and melt-crystallized films of various molecular weights prepared in different crystallization conditions were studied with the help of thermoluminescence technique using high frequency glow dicharge Ar plasma for surface activation. Molecular mobility in a bulk of the same samples was investigated by the method of radio thermoluminescence, in which a deeply penetrating γ-quanta from 60Co radiation was used for activation of the bulk. A marked difference in a temperature position of the peaks on the glow curves of plasma-induced thermoluminescence and those of radiothermoluminescence correspoding to γ- and ß-transitions was found to depend on crystallisation conditions and molecular weight. Quasi-independent segmental mobility (ß-relaxation) in the near-surface nano-layers of UHMWPE reactor powder particles synthesized at low temperatures appeared to be unexpectedly unfreezed at the temperature higher than that in the bulk. It was supposed that this happend because of crystallization under the confinement conditions during low-temperature polymerization leads to formation of a specific surface structure.

Composites based on n-alkane and nanoscale additives were investigated to determine the efficiency of heat transfer during phase transitions in phase change materials. It was found that the thermal conductivity of composite materials is several times higher than the thermal conductivity of the initial n-alkane. The observed effect is due to the specificity of the supramolecular nanostructure of the composite, which differs from the supramolecular structure of the nonadecane.

The kinetics of the first-order solid-state structural transition in monodisperse n-alkanes samples of even tetracosane C24H50 was studied by FTIR spectroscopy. The existence of many irregular conformers in solid phases of tetracosane, the concentration of which reaches a maximum when approaching the melting temperature, has been demonstrated. The existence of these defective molecules promotes transitions between different rotator phases in the solid state.

Aiming at finding the proper UHMWPE reactor powders convenient for solvent-free technology producing high-strength fibers, the comparative study of the near-surface layers of the commercial and lab-scale UHMWPE reactor powders was carried out with the help of the thermoluminiscence method. The difference in the powder glow curves and changes in them after subjecting the powders to various processing (compaction and sintering) were observed. Decomposition of the curves was carried out using Fityk program. The energy activation of the electron trap erosion, and the relative content of the shallow and deep traps in the samples investigated were calculated. The association of these observations with the mechanical propeties of the end sintered oriented product is discussed.

The kinetics of the first-order solid-state structural transition in monodisperse n-alkanes samples of odd tricosane C23H48 and even tetracosane C24H50 was studied by FTIR spectroscopy. The initial nuclei location of the new phase was revealed. The process of crystal structure rearrangement is initiated in the interlayers between neighboring lamellar for odd tricosane, while the nanonuclei in even tetracosane arise in the crystalline lamellas cores. Thus, the influence of the number evenness of carbon atoms in the n-alkanes chains on the first-order structural phase transition has been proved.

The subject of the research is the interconnection between the installation of a dishwashing machine in a household and the change in consumption of such primary resources as electric energy, cold and hot water. Applicability of this research is defined by the high growth of various electric appliances in the households, and the dishwashing machine has one of the highest tempos of the increase over the last decade. The results of this research allow esteeming the future change in the structure of consumption of energy sources by the households in terms of mass implantation of dishwashing machines in our daily life. Several methods of estimation have been reviewed of how the installation of the dishwashing machine impacts on energy sources consumption in the household. Mathematical descriptions and the rationale for the statistical data analysis methods of household energy sources consumption, which were used are explained. Based on the analysis of statistical data over 5 years before the installation of the dishwashing machine, the consumption of the sources is forecasted for the sixth year upon condition that there is still no dishwasher. At the beginning of the sixth year, the dishwashing machine was installed in the observed household. Forecasted values of household sources consumption for the sixth year have been compared with actual values which were obtained after installation of the dishwasher in the household.

One of the most important factors affecting poultry productivity is the quality of drinking water. Modern preparations of foreign production that allow to remove biofilm from the water supply system along with all organic and inorganic pollutants are expensive, as well as, as a rule, negatively affect the body of poultry when drinking. The article considers the effect of water solutions of neutral anolyte “ANOLIT ANK SUPER”, as well as a solution of the preparation “DUTRION” on the intestinal microflora of poultry. As a result of the experiment, it was found that the use of 0.25% and 10% solutions of neutral anolyte, as well as the solution of the preparation “DUTRION” has a multidirectional effect on the level of bifidobacteria and lactobacilli in the intestine, but at the same time reduce the level of pathogenic and conditionally pathogenic microflora.

Monte Carlo method modeling allows determining the transformation of the probability density function of the uncertainty of the impedance components measurement results. Direct measurements of impedance components are based on the indicative form. The probability distribution density function of the uncertainty of direct measurement results is a constant. The components of algebraic and trigonometric forms of impedance are measured indirectly. The type of transformed probability density function for these forms is determined by calculating estimates of mean, standard uncertainty, extended uncertainty, asymmetry coefficient. Modeling allows to obtain reliable estimates of extended uncertainty of indirect measurements results of impedance components in accordance with current metrological standards.

The dependence of the IR absorption spectrum on the type of symmetry of crystallographic cells allowed us to investigate the kinetics of phase transitions. It is confirmed that the first order solid-phase transition develops by a heterogeneous mechanism in a narrow temperature range ΔT ⩾ 1 K.

The article is devoted to the methods of analysis of the surface water layer of oceanic, marine and inland water basins. Due to water pollution, the optical properties of the surface layer are changed. The temperature field in the surface layer is locally transformed. This has a serious impact on the maintenance of the current structure. Water quality is changing. The conditions of existence of flora and fauna are changing. The article analyzes the indicators that determine water pollution. Absence of common energetic characteristic of a condition of a surface water layer is specified. It is proposed to estimate the dynamic picture of the heat absorption process. To do this, a gradient energetic criterion is introduced. The numerator of this criterion shows the intensity of the absorbed solar energy flux by the surface layer with a thickness of 1 m. the Denominator is the magnitude of the maximum possible absorption of the radiation flux. This maximal radiation flux is taken to be the value of the solar constant. The absorption of flow is considered to be evenly. This means linear temperature distribution. The depth of absorption to be a certain predetermined depth at which almost the entire stream of solar radiation is absorbed. The gradient criterion for the contaminated surface layer is several times higher than its value for clean water. That is, the gradient criterion captures the rapid overheating of the surface layer of the polluted water basin. This process, in particular, leads to the displacement of water currents. This is due to the fact that the bulk of the moving layer is at the surface. Also gradient criterion shows the danger of this local overheating for living organisms.

A model resulting in charge ordering (CO) similar to that observed in cuprate superconductors is under study. It includes strong long-range electron-phonon interaction (EPI) and high density of correlated carriers. Coexistence of large bipolarons and delocalized carriers is a feature of such system. We develop generalized variation method to calculate the bipolaron size (CO period) in the ground normal state of such system at various doping. The approach allows the revealing of a possible physical reason of strongly different doping behavior of the CO wave vector in different cuprates. Obtained doping dependences of the CO period and temperature of the CO decay demonstrate quantitative agreement with those observed in cuprates. Predicted in the suggested approach ratio of the CO wave vector to the wave vector of the high-energy anomaly (HEA) in ARPES spectrum is in consent with that in cuprates. Calculated resonant x-rays scattering on the CO emerging in the model is in good agreement with experiments on cuprates including the asymmetry of the CO peaks' cross-section. A gap arises in the spectrum of delocalized carriers near antinodal direction due to their scattering on the periodic potential created by autolocalized carriers, analogously to photon crystal effect.

X-ray diffraction analysis of solid-state compaction/sintering-induced changes in crystalline structure of lab-scale (M332) and commercial UHMWPE (X600) reactor powders has been carried out. The profile fitting programs TOPAS-5 and Peakfit 4.1 have been used to deconvolute the overlapping peaks. The linear FWHM of (110) and (002) X-ray peaks have been taken for calculation of the transverse (D110) and longitudinal (D002) crystallite sizes with the help of Sherrer method. The growth of crystallite sizes in cold compacted powders with sintering has been detected in both directions. Besides, the sintering has resulted in the generation of the planar a-texture, more pronounced in the lab-scale UHMWPE samples. As known, orientation hardening of the sintered reactor powders is an alternative route to UHMWPE high performance fibers distinct from the common gel-technology. It has been found that the highly oriented thin film threads produced from highly textured sintered material demonstrated the extremely high tensile strength up to 3.0 GPa, close to that of gel-fibers (3.5GPa) [1] while X600 less textured powders has shown low compactability and drawability.

The efficiency of radiation defects formation in alkali halide crystals (AHC) was studied by the method of absorption spectroscopy. However, it is not possible to study the deformation-stimulated processes in detail by the absorption spectrum of radiation defects due to the limited sensitivity compared with luminescent spectroscopy. In this regard, thermally stimulated luminescence (TSL) of radiation defects at elastic and plastic deformation was applied in AHC. In the absence of deformation, the dominant peaks in TSL are -centers. After elastic deformation, low temperature peaks of TSL corresponding to F'-, VK- and VF-centers became dominant. After plastic deformation, the peaks of TSL corresponding to -centers became dominant. The elastic deformation contributes to the increase in concentration of low-temperature F'-, VK- and VF-centers, and the plastic one contributes to that of high temperature -centers (peaks of TSL in KCl at 360K, in KBr at 365K, in KI at 340K), composed by divacancies created by plastic deformation. At elastic deformation, unrelaxed interstitial halogen atoms are converted into VK- and VF-centers, and due to this fact the long-range interaction is absent, the result of which are the -centers.

The novel mechanisms of polaron pairing in complex oxides and the possibility of high-temperature superconductivity as a result are reported. The peculiarity of complex oxides is taken into account by considerations of a medium with two optical phonon branches satisfying the adiabatic condition of the polaron theory and having different dispersions. The system of nonlinear motion equations for the coupled fields of carriers and polarization is solved. It is shown that two carriers localized because of their interaction with one phonon branch form a bipolaron owing to the interaction with the real phonons of another branch under the resonance condition. Such a novel bipolaron does not need a high static dielectric constant (SDC) for its formation, distinct from other bipolaron models. The novel bipolaron is energetically favourable compared with other bipolarons, when SDC is not high. By taking into account the peculiarity of bosons having a low maximum velocity, the expression for their condensation temperature is modified. As a result, the high-temperature Bose condensation of the novel bipolarons is shown to be possible at lower concentrations even if their effective mass is very large.

By using luminescence spectroscopy, we have established the influence of low-temperature uniaxial deformation on the configuration of a self-trapped exciton (STE) in alkali halide crystals (AHC) at the instant of radiative relaxation. In face-centered crystals, there occurs the redistribution of the luminescence intensity from the asymmetric configuration of STE to the symmetric one (III → II → I- types), whereas in volume-centered crystals, on the contrary, the evidence counts in favour of the asymmetric configuration of STE (I→ II–types). The external deformation in the direction leads to an effective sliding of anions in the direction that coincides with the direction of the STE squeeze which classically makes for the creation, of the symmetric STE configuration in the direction, acting perpendicularly to the STE’ length results in their stretching, which in turn brings into the creation of the asymmetric STE configuration with a higher degree of the polarization.

The single crystals LiF with copper impurity were grown by Czochralski method. The concentrations of Cu in the crystals were 0,0004-0,002%. In order to determine a copper valence impurity, measurements of the ESR, emission, excitation and absorption spectra were performed. We found emission peak at 410 nm and excitation peak at 250 nm. In agreement with reference, these peaks point to presence of Cu+ in our samples. The mechanisms of capture and recombination providing process of thermoluminescence were recognized.

Tribological materials from the wheel and the wheel chock of a railway train were studied. The samples were taken from new and used wheels and wheel chock. Experimental x-ray absorption near edge spectra (XANES) spectra above the Fe L2,3 edges show the variations in the shape of the Fe L 2,3 edge fine structure, that correspond to the formation of Fe oxidized layer during the process of dry friction. Elemental analysis shows the large variations of element's distribution along the surface within 10 nm depth of damaged sample.