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The paper presents the results of the studies of a matrix based on borophosphate glass (BFS) with the addition of lithium chloride as a simulator of spent electrolyte, a type of radioactive waste formed during the pyrochemical processing of spent nuclear fuel. Based on the results of X-ray phase analysis and scanning electron microscopy, the phase composition and microstructure of the glasses were evaluated – the amorphous structure and homogeneity of the obtained material were confirmed. Using differential scanning calorimetry and thermal conductivity measurements, the thermophysical properties of the material are described, and it is shown that the inclusion of LiCl does not affect the glass transition temperature for the obtained glasses which equals ~410 ?C. However, the addition of lithium chloride affects the electrical conductivity properties studied by electrochemical impedance spectroscopy. Tests of mechanical strength and hydrolytic stability were carried out in accordance with the established requirements for the matrices for immobilization of radioactive waste. When studying the morphology of the glass surface in contact with water, the formation of a diffusion layer is observed as a result of the transition of sodium ions into a solution.
The performed studies confirm the possibility of using glasses of the selected composition as a matrix for immobilization of the spent electrolyte based on lithium chloride.
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The precursor powder and luminescent ceramics YAG:Ce based on it were obtained by reverse chemical deposition. The influence of sintering additives (CaO, MgO and TEOS), the concentration of the activator Ce3+, the temperature of vacuum sintering, as well as the temperature of air annealing on the luminescent properties of YAG:Ce ceramics has been studied. The following parameters have been identified as optimal parameters for the manufacture of YAG:Ce ceramics in terms of luminescence efficiency. The concentration of the sintering additive is 0.01 f.u., the type of sintering additive is TEOS, the vacuum sintering temperature is 1800 ?C, the air annealing temperature is 600 ?C for samples with TEOS. A sample with a luminescence efficiency of 319 Lm/W was obtained when exposed to 190 mW laser radiation with a spot diameter of ~5 mm.
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The results of a study of dielectric properties and harmonic coefficient for barium titanate ceramics obtained from a mixture of BaTiO3 powders with particle sizes of 400 and 50 nm at different sintering temperatures are presented. It is shown that when the content of the finely dispersed component changes from 0 to 100 %, the dielectric constant ?(x) and the harmonic coefficient ?(x) are non-monotonic, reaching a maximum at x equal to 0.25 and 0.30. This dependence may be due to a change in packing density when the percentage composition of the components changes.
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For the first time a series of ceramic powders of the composition (Y1–xLux)3Yb0.15Er0.03Al5O12 (YLuAG) with a garnet structure in which the atomic ratio of Y3+/Lu3+ cations varied from 80/20 to 20/80, were synthesized using the chemical coprecipitation method. It was determined that the process of garnet phase formation under the synthesis conditions used occurs through the formation of intermediate phases, the composition of which depends on the Y/Lu ratio in the solution of the initial salts. Based on the results of differential thermal analysis of precursor powders and X–ray diffraction of ceramic powders of the composition (Y1–xLux)3Yb0.15Er0.03Al5O12, calcined at 800, 900, 1000 and 1150 ?C, the temperature ranges of formation and decomposition of intermediate crystalline phases Y2O2SO4, Y2(SO4)3, Lu2(SO4)3 and Lu1–xYxAlO3, formed in the process of temperature synthesis of the phase with the garnet structure, were determined.
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A methodological approach to developing hardware and software solutions for debugging and testing algorithms and control systems for actuators of a glass-forming machine in real time is presented. During model tests, the algorithms’ compliance with the technical specifications and their reliability were assessed. Testing was performed on a test bench built on the basis of an industrial sample. The bench simulates the operation of the object, the parameters are recorded and transferred to the monitoring system for post-processing. During the tests, the component base of various manufacturers available under the sanctions policy was checked. It was confirmed that such a bench is applicable for rapid prototyping of control algorithms, conducting semi-naturalistic testing, and training specialists in the glass industry. Independent control of the process control system will contribute to the engineering of industrial equipment, mastering critical technologies and, ultimately, forming the technological sovereignty.
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Using the methodology of system analysis, the paper analyzes the growth prospects of ceramic membranes, market volume and value, as well as the prevailing commercial trends in the industry by the most common segments: application, technology, regions and materials. The industry needs and dynamics of the Foreign and Russian membrane market are analyzed. Sales forecasts for the ceramic membranes industry up to 2029 are presented. The main growth factors of the global ceramic membranes market are given. The feasibility and relevance of the industry development in Russia is substantiated. Examples of companies of the world leaders of the ceramic membranes market are given.
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Polishing suspensions and powders presented on the world market for polishing a wide range of optical parts used in the manufacture of laser gyroscopes are considered. Their main technical parameters determining the quality of the resulting polished surfaces of optical parts are given. A list of polishing suspensions and powders most suitable for the manufacture of optical parts of laser gyroscopes is proposed.
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Diagnostics of magnetic susceptibility of ferroimpurities (present in the raw components of glass and ceramic products), for the removal of which magnetic separation is widely used, can be carried out using a new magnetic rheological method. Three options for its implementation are described. Results ferroimpurities’ magnetic susceptibility determination, consisting in natural sand and feldspar, are obtained.
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An energy- and resource-saving plasma technology for glazing autoclaved building materials has been developed. It has been established that the introduction of colemanite into the initial charge makes it possible to increase such performance indicators as frost resistance, water resistance and microhardness. The features of the formation of the macro- and microstructure of the glaze coating when treating the front surface with a plasma jet were studied.Key words: glazing, plasma jet, autoclave hardening wall materials, water resistance, frost resistance, microhardness.
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It is shown that the extracted natural quartz sands, widely used in glass, refractory, ceramic, foundry and other industries, as a rule, do not meet the requirements for granulometric composition set by industry standards. Studies have been conducted and an effective method of processing quartz sands has been proposed in order to improve the granulometric composition using a cross-flow pneumatic separator.
