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• VOL 93, No. 7 (2020)

Various options for transport and technological schemes for unloading and storing substandard quartz sand used for the preparation of glass batch in compound shops are considered. The possibility of using quartz sand without additional processing in drying drums is noted. A method and a device for unloading bulk material from dump trucks with increased carrying capacity into receiving bins of small volume are presented.

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• VOL 93, No. 7 (2020)

The results of studies of performance indicators of samples of foam glass concrete building products are presented. For a more visual representation of the possibilities of using products in various conditions, the indicators are conditionally divided into strength and energy. Strength includes density and compressive strength, energy - thermal conductivity and moisture resistance. The qualitative results of the influence of the main parameters of the main filler of products - ground glass - on performance indicators have been investigated. Nomograms have been developed to determine the rational ratio of the output indicators of products in relation to various technical and operational requirements

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• VOL 93, No. 7 (2020)

The paper presents a study of the possibility of obtaining artificial porous aggregates for lightweight concrete based on household cullet and various types of ash and slag waste from thermal power plants: ash disposal, slag and ash and slag mixture from the ash dump. The influence of the type and amount of ash and slag waste in the composition of the charge, as well as the temperature and time of firing, on the final properties of the material has been investigated. The properties are determined and photographs of the macro- and microstructure of the obtained experimental samples of artificial porous filler are presented.

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• VOL 93, No. 7 (2020)

The analysis of the main reasons for the formation of efflorescence in brickwork in the Aral Sea regions is presented. It has been established that as a result of alternating moistening and drying of the building material, during which the crystallization of salts in its pores occurs, the formation of high-water crystalline hydrates with an increase in volumes exceeding the pore volume of the material leads to the appearance of pressure that destroys the building material. External signs of salt corrosion are peeling and chipping of ceramic bricks. The features of salting out in ceramic bricks in the Aral Sea conditions are indicated.

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• VOL 93, No. 7 (2020)

The object of the research is ceramic material taken from the fortress wall of the city of Girona. The chemical composition of the test material showed an increased carbon content (13.1 & # 37;), which indicates the introduction of fuel into the raw material. The increased content of fuel in the raw material contributes to the formation of porosity and uniform sintering inside the ceramic specimen. Integral and differential porograms of the samples under study, obtained by the method of mercury porosimetry, showed that the total volume of micropores ranging in size from 10-4 to 10-8 m is 0.155 cm ³ / g. The differential distribution of micropores, depending on their size, is as follows: 10-4? 10-5 - 27 & # 37; (backup - non-hazardous); 10 ? 5 ? 10 ? 6 m - 19 & # 37; (dangerous); 10? 6? 10? 7 m? 29 & # 37 ;; 10? 7? 10? 8 m? 25 & # 37; (non-hazardous)

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• VOL 93, No. 7 (2020)

Microstructural studies of ancient Issyk-Kul ceramics were carried out using a scanning electron microscope, which allows not only to see the mutual arrangement of mineral particles, pores and microcracks, but also to carry out a quantitative analysis of the main microstructural indicators. Ceramic samples from the valley of Lake Issyk-Kul (Kyrgyz Republic), where the ruins of many ancient settlements are located

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• VOL 93, No. 6 (2020)

The kinetics of the electroflotation process of extraction of TiO ₂ and TiN powders from wastewater has been investigated. Experimental results show that stationary values ??are reached in 20 & mdash; 25 minutes The degree of electroflotation extraction of titanium nitride powder without additive is low and amounts to 15 - mdash; 20 & # 37 ;. Introduction of anionic surfactant NaDBS and cationic SeptaSurfactant increases the degree of extraction in NaCl up to 50 - mdash; 65 & # 37; and up to 45 & mdash; 60 & # 37; in Na ₂ SO ₄ . An increase in the degree of extraction of TiN is associated with the hydrophobization of the surface and an increase in the size of the particles of the dispersed phase. The highest recovery rates are obtained by adding coagulants and a coagulant - surfactant composition. In Na ₂ SO ₄ solutions, two compositions Al ³⁺ & mdash; NaDBS and Fe ³⁺ & mdash; NaDBS, the recovery is 96 & # 37 ;. High values ??of the degree of recovery are observed for TiO ₂ when adding compositions Al ³⁺ & mdash; Surfactant and Fe ³⁺ & mdash; Surfactant

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• VOL 93, No. 6 (2020)

A new technology for laser cutting glass along a curved contour is described, which combines the combined use of two different cutting methods in one technological cycle: the method of laser controlled thermal splitting on straight sections of the cutting contour and the filamentation method using a picosecond laser on curved sections of the contour. The proposed technology allows to significantly increase the productivity of the cutting process along a curved contour without deteriorating the strength characteristics of glass products

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• VOL 93, No. 6 (2020)

Nanocrystalline powders of LiZnMn ferrite were obtained by the method of solution combustion at various glycine-nitrate ratios (G / N = 0.2, 0.4, ..., 1.4). Elemental analysis showed that the composition of the obtained samples corresponds to the spinel ferrite Li _0.45 Zn _0.05 Mn _0.06 Fe _{2 , 43} O ₄ . Based on the SEM results, it was found that the compositions have a porous microstructure and a developed surface, and the X-ray phase analysis data indicate that the synthesized LiZnMnFe spinel is single-phase and has a high degree of crystallinity (up to 99 & # 37;). It is shown that the magnetic and dielectric characteristics of the obtained samples change systematically depending on the selected redox ratio of the reaction mixture and reach maximum values ??at a stoichiometric value of G / N = 0.6

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• VOL 93, No. 6 (2020)

A porous, catalytically active membrane based on coarse silicon carbide has been synthesized. To synthesize the membrane, ultradispersed additives of the eutectic composition of magnesium oxide and silicon carbide were introduced into the initial SiC powder, which, during sintering at temperatures in the range from 1100 to 1450 & # 176; C, form a liquid phase in the form of clinoenstatite MgSiO _{3 , which wets the coarse SiC particles and forms a porous strong membrane framework. The dependence of the pore size of the ceramic material on the pressing pressure was investigated, which made it possible to obtain a highly porous ceramic membrane with pores of the most optimal size for the dehydrogenation of ethylbenzene to styrene. To give the synthesized membrane the catalytic properties required for the dehydrogenation process, the pore surface is modified to 10 & # 37; Re & ndash; W active ingredients using the alkox method}