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The dependence of the ignition temperature, combustion rate and composition of the resulting products on the concentration of Ti + C in mixtures with powder of a high-entropy alloy (HEA) FeNiCoCrCu and the initial mixture of metals forming it (MIX) has been studied. HEA was obtained by mechanical activation (MA) of a mixture of metal powders in argon. At the melting temperature, the high-entropy FeNiCoCrCu alloy decomposes into several phases, but the basis of the HEA alloy, as well as the alloy obtained by melting and crystallizing MIX, is a 5-component phase with an average formula Cu1.2Fe1.4Ni1.4Co1.4Cr. In addition, 5, 4, and 3-component phases with averaged formulas Cu2Ni2Co2Fe2Cr, Cu3Ni3Co2.9Fe2.5Cr, Cu4.8Ni4.5Co4.6Fe4.2Cr, Cu40Fe2Ni4Co2C, Cr12.5Fe3.2Co2.6Ni and Co3.2 Fe3,5 Cr are present in small amounts in the binder. Experiments on the ignition and combustion of mixtures of MIX and HEA with Ti + C were carried out in argon at atmospheric pressure. The combustion rate, ignition temperature, and maximum temperature reached in the thermal explosion of MIX and HEA mixtures with Ti + C increase with increasing Ti + C concentration. Due to the low exothermicity of the mixtures, the experiments were carried out at an initial temperature of 500 °С. At this initial temperature, the combustion limit of the samples occurs when the Ti + C concentration in the HEA and MIX mixtures is less than 30 %. Based on the results of scanning electron microscopy, the volume concentration of the number of titanium carbide (TiC) particles in molten samples was calculated. In an alloy with a HEA binder, the number of TiC particles per unit volume is 1.5-3.0 times greater than in an alloy with a MIX binder, and their size is correspondingly smaller. With an increase in the concentration of Ti + C from 30 to 40 % in a mixture with HEA, the number of TiC particles per unit volume decreases. In a mixture with MIX, the number of TiC particles per unit volume passes through a minimum. This is due to two opposite processes: on the one hand, the probability of the generation of TiC particles increases, on the other hand, their coagulation occurs.

The article reveals the role of digitalization in the development of agricultural production in the Republic of Belarus and ensuring national food security. The main trends in the digital transformation of the agricultural business are identified, the level of penetration of modern information and communication technologies into the main production processes is analyzed; the prospects for the process of digitalization and intellectualization of domestic agriculture are determined in the context of the tasks set by the state and the availability of developments of companies in the field of digitalization of agriculture. Based on statistical data, conclusions were drawn about the possible pace of digital transformation of the agricultural sector. Particular attention is paid to the applications of the Internet of Things technologies, artificial intelligence in precision farming, as well as the best Russian experience in this area.

Heterotaxy syndrome is a congenital malformation in which the internal organs of the chest and abdominal cavity have an abnormal location. People suffering from this syndrome have multiple complex defects in the heart, blood vessels, spleen, liver, lungs and other organs. Heterotaxy is a rare pathology that requires a multidisciplinary approach to diagnosis. This article demonstrates a rare case of heterotaxy observed in the pulmonology clinic of the Veltischev Institute.

Combustion of powders of transition metals of titanium PTS (average particle size 57 μm), zirconium PCRK-1 (12 μm), tantalum Ta PM-3 (8 μm), hafnium GFM-1 (4 μm), niobium NBP-1a (21 μm) with carbon black grade P-803 dispersion 1–2 μm was studied. The combustion process of the compressed samples (mass 2.5–6.9 g, height 1.2–1.7 cm, relative density 0.55–0.61) was performed in an inert argon medium at a pressure of 760 mmHg in the constant pressure chamber. Combinations were studied, Me1 + Me2 + Me3 + Me4 + 4C, Me1 + Me2 + Me3 + Me4 + Me5 + 5C. XRD patterns of the mixtures were recorded on a DRON-3М diffractometer (CuKα-radiation). Combustion product sections were studied using a LEO 1450 VP scanning electron microscope (Carl Zeiss, Germany). The fractional composition and particle size distribution of the mixture were determined according to standard procedure using a Microsizer-201C laser particle size analyzer. Combustion velocity, elongation of samples, phase composition of products were determined. The maximum combustion temperature of the mixture (Ti + Hf + Zr + Nb + Ta) + 5C was measured experimentally for the first time. The morphology and microstructure of the reaction products were also observed. Combustion products of mixtures (Ti + Zr + Nb + Ta) + 4C and (Ti + Zr + Nb + Hf) + 4C contain high entropy carbides, which are solid solutions with the same structural type B1 (space group Fm-3m) and having different cell parameters. Product samples of mixtures (Ti + Zr ++ Hf + Ta) + 4C and (Ti + Hf + Zr + Nb + Ta) + 5C contain high entropy and medium entropy carbides, also representing solid solutions with the same structural type B1 (space group Fm-3m). The results of this work can be used in the production of high-entropy and medium-entropy multicomponent carbides.

The modern structure of the republican association “Belagroservice” is determined. A deep and comprehensive analysis was carried out, as well as an assessment of the production and financial condition of domestic agroservice organizations. At the same time, accounts receivable and accounts payable were studied, the structure of revenue and the profitability of certain types of agroservice works and services were considered. Promising directions for the effective functioning of agroservice organizations at the present stage have been developed.

The use of local anesthetics reduces the intensity of pain stimuli during invasive procedures, thereby reducing postoperative pain intensity. The aim of the study was to determine the onset, duration and extent of regional blocks of the infraorbital nerve and its branches performed by injecting lidocaine and lidocaine-bupivacaine mixture into the infraorbital canal in dogs. Ten clinically healthy dogs, selected according to the principle of clinical analogues, were selected for the trial. Under general anesthesia, a pain stimulus was initiated by needle injection from the dorsolateral side into the gingiva of the maxillary canines, maxillary fourth premolars, and second molars. Changes in physiological indices were recorded on the patient's monitor.Heart rate and respiratory rate were measured. After baseline physiological indices were measured, 1 ml of 2% lidocaine solution was injected into the infraorbital canal (about two-thirds of the canal length) in one group and a mixture of 2% lidocaine and 0.5% bupivacaine (0.5 ml each) in the other group. Data were recorded for 4 hours.When infraorbital nerve blocks were performed in the first and second experimental groups of animals, anesthesia of the maxillary canine on the anesthetized side was achieved in 5 and 10 minutes, respectively. But nerve blocks of the fourth premolar and second molar were successful only in 2 dogs of the first group and 1 dog of the second group, respectively. The average duration of nerve block for the maxillary canine was 110 and 203 minutes after injection of lidocaine and lidocaine-bupivacaine mixture, respectively.Performing an infraorbital nerve block, as was done in this study, successfully blocks the innervation of the maxillary canine, but the results of nerve analgesia of the fourth premolar and second molar were inconsistent. This specific technique should not be used when extracting teeth caudal to the maxillary canine.

The article briefly shows the main ways and directions in improving repair and servicing base of livestock farms and complexes, as well as the direction in terms of improving the technology and equipment in the repair and service industries in the livestock industry in the Republic of Belarus.

A number of important points and indicators characterizing the current state and potential of the Belarusian agricultural production are considered. It has been established that over the past decade in the agricultural organizations of the republic there was a decrease in the energy supply indicator by 15 %, and the power supply to labor during this time increased by more than 1.4 times. The overall efficiency of agricultural and livestock production, the level of labor productivity in an agricultural organization, the availability of energy capacities has a very significant and often decisive impact.

Long-term foreign and domestic experience in agricultural production proves that the intensification of agricultural production, an increase in its efficiency and volumes, an increase in the competitiveness of agricultural products, is impossible without constant modernization of the production and technical base and the introduction of the most modern achievements of scientific and technological progress. Only a comprehensive and systematic technical and technological reequipment of agricultural production, saturation of it with high-tech, high-performance complexes, machines, equipment can provide a significant increase in labor productivity, minimize the cost of all types of material resources with a steady trend of constantly decreasing labor resources in agricultural production. The analysis of indicators of provision with the main types of machines of domestic agricultural enterprises in comparison with different countries of the world is carried out. The article presents the results of the analysis of the most important segments of the agricultural tractor and combine park of the Republic of Belarus.

The article presents a conceptual overview of modern approaches to accounting for depreciation of machine and tractor fleet in agrarian production used in different countries of the world. The emphasis is placed on the agricultural specifics, which determines the use of certain methods and tools for calculating depreciation charges. The mechanism of the influence of the operating conditions of agricultural machinery on the choice of the organization’s depreciation policy, as well as the distinctive principles of management accounting for depreciation at agricultural enterprises, is disclosed, the possibilities of taking into account a number of specific factors in the process of determining depreciation are considered – inflation, uneven operation of equipment, its repair cycle, etc. The problem of scientifically based distribution of the value of long-term assets over time is touched upon.

We have studied the influence of the combustion temperature of Al + AlN mixtures in nitrogen and the cooling time of the synthesis products on the content of oxygen impurities dissolved in the aluminum nitride lattice. The results demonstrate that, in the temperature range 1460–2000°C, surface oxygen is incorporated into the structure of AlN. It has been shown that, with increasing synthesis temperature, the content of oxygen dissolved in aluminum nitride rises. The concentration of dissolved oxygen is higher in the case of a finer particle diluent (AlN). Raising the synthesis temperature leads to aluminum nitride grain growth and coalescence, characteristic of secondary recrystallization. We demonstrate that, to reduce the concentration of oxygen impurities dissolved in aluminum nitride, the starting mixture should contain additives facilitating the reduction of aluminum oxide or surface oxygen vaporization.

We studied the effect of the H2S donor (NaHS, 1-500 μM) on the contractile responses of isolated aortic smooth muscle segments from rats with metabolic syndrome induced by high-fat, high-carbohydrate diet. It was found that the vasorelaxing effect of NaHS (5-100 μM) decreased in under conditions of MS. The endothelial NO synthase inhibitor L-NAME (100 μM) suppressed the effect of NaHS, while cystathionine-gamma-lyase inhibitor PAG (100 μM) decreased the vasodilating effects of acetylcholine (0.1-100 μM). Application of endogenous NO precursor L-arginine (1 mM) potentiated in the effects of H2S donor NaHS. Thus, the contractile activity of vascular smooth muscles in metabolic syndrome is determined by not only the effect of H2S, but also the influence of NO.

A thermodynamic model is proposed for condensed phases in the ternary system U–Zr–N in the range 298–2800 K. The model is based on previously reported models of the constituent binaries U–Zr, U–N, and Zr–N and available data on the properties of the pseudobinary system UN–ZrN. It allows one to calculate phase equilibria involving liquid phase. The model is used to calculate a number of isobaric–isothermal sections in the U–Zr–N system.

Surface-waterlogged soils drained by ceramic and plastic drainage are an analogue of large-area lysimetric installations, the drainage runoff in which is represented by gravitational waters similar to lysimetric waters. The drainage runoff module in spring and autumn and its dependence on the humidity of the year have been determined on test plots drained by plastic and ceramic drainage. It is shown that drainage transforms the stagnant-washing water regime into the washing type. The long-term and spatial dynamics of the removal of the clay fraction of soils and iron compounds has been studied. The leaching of chemical elements with drainage runoff and its effect on the intensity of lessivage in agro-gray drained soils have been revealed.