Highly pure quartz of the Ural type is a world-class raw material source for melting transparent quartz glass with unique characteristics: the total content of all impurity elements (Al, Fe, Ca, Mg, Na, K, Ti, Li, B, Cr, Ni, Mn , Cu) in enriched quartz concentrates does not exceed 10 ppm, and the content of the sum of alkaline elements (Na, Li, K) is in the range of 0.37 - 0.94 ppm. These indicators were achieved due to the natural features of quartz of metamorphogenic-metasomatic genesis and the enrichment schemes developed for it. Resources of this type are concentrated within the Kyshtym granular quartz deposit in the Urals
Powder of calcium carbonate CaCO 3 (calcite) with a particle size of 100-200 nm and a shape close to isometric was obtained by heat treatment at 600 ° C of a product synthesized from a 2M aqueous solution of citric acid H < sub> 3 C 6 H 5 O 7 & middot; Н 2 О and commercial calcium carbonate powder CaCO 3 (calcite) with a particle size of 1 - 4 microns of a prismatic shape. The sequence of chemical transformations of CaCO 3 & # 8594; CaC 6 H 6 O 7 3H 2 O / Ca 3 (C < sub> 6 N 5 O 7 ) 2 & middot; 4Н 2 O & # 8594; CaCO 3 allows you to change the properties (size and shape) of the calcium carbonate powder CaCO 3 . Due to these properties, the obtained highly dispersed CaCO 3 calcite powder can be recommended as a filler for obtaining unique composites with inorganic (glass, ceramic, cement) or polymer matrices.
The results of studies of the structural-phase state and physicomechanical properties of coatings of the Al-Si-N and Zr-YO systems with a thickness of 3 ?m, obtained by the method of pulsed magnetron deposition on the surface of single-crystal m-Si, are presented. In the course of the studies carried out, it was found that the light transmission coefficient in the visible region of the spectrum for coatings Al-Si-N and Zr-YO reaches 83 and 78 & # 37; respectively. The results of the study of mechanical properties showed that the crack resistance of m-Si samples with protective coatings is 2-3 times higher than that of the original silicon samples. The results of laboratory tests of the resistance of the studied samples to shock loads when interacting with a flow of high-speed (5 - 7 km / s) solid microparticles of Fe showed that the deposition of protective coatings 3 ?m thick on m-Si samples makes it possible to suppress the processes of erosion of the surface of the latter by preventing the formation of small craters
An energy- and resource-saving technology has been developed for producing decorative plasma coatings on sheet glass using finely ground glass powders based on colored glass containers and broken glass. The possibility of using exhaust plasma-forming gases for preheating sheet glasses before plasma spraying of finely ground glass powders has been substantiated and practically confirmed. A number of operational and physical and mechanical characteristics of sheet glasses with sprayed coatings have been investigated.
A study of the change in the state of the polished surface of optical glasses of STK19 and OF4 grades by ellipsometry, IR spectroscopy and measurement of sample roughness under the influence of the environment has been carried out. It is shown that the state of the surfaces changes immediately after the completion of polishing and does not change during the entire holding period. Changes in external conditions (temperature and humidity) lead to a further change in the state of the surfaces. The surface treatment of optical glasses in HMDS vapors prevents the penetration of corrosion into the glass and prevents an increase in roughness
On April 8, 2020, a world-class scientist, Doctor of Technical Sciences, Professor Vladimir Stepanovich Kondratenko celebrated his 70th birthday! V. S. Kondratenko is the creator of a new scientific direction in the field of precision processing of a wide class of multifunctional materials, based on the developed methods of laser controlled thermal cleaving of brittle materials, laser welding of quartz glass with deep penetration, as well as chemical-mechanical grinding and polishing using new types of bonded diamond abrasive tool. The method of laser controlled thermal cleavage confidently holds the palm in the performance of separation of brittle non-metallic materials.
Samples of electrodes with an active layer based on TiO 2 , RuO 2 and oxides of rare earth elements Ce, La, Nd, doped with carbon nanoscale, have been obtained. The morphology of oxide electrodes was studied. Their electrochemical behavior in aqueous solutions of sodium chloride and sulfate was studied. The values ??of the current-free potentials, the values ??of the current densities and the potential regions for the release of chlorine and oxygen from aqueous solutions of sodium chloride and sodium sulfate have been determined. The dependences of the volume of released chlorine on the composition of the electrodes are presented.
Made porous ceramics based on clay and non-plastic aluminosilicate raw materials of Uzbekistan by slip casting. Molding was carried out using a blowing agent - technical foam and sawdust, stabilizing the structure, followed by firing at 1300 - 1350 ° C. The effect of various fillers on the physical and technical properties and microstructure of samples after sintering has been studied. It has been established that ceramics with a density of 700 - 900 kg / m 3 and a strength of 1.6 - 11.0 MPa can be obtained by foam technology with a mass content of foam from 15 to 25 & # 37 ;. Porous samples with the finest structure of grains and pores, obtained on the basis of Samarkand chamotte
A number of charge compositions with anthracite as the main blowing agent have been developed. The density and strength of the synthesized samples have been determined. The process of formation of a cellular structure of a heat-insulating cellular glass as a result of thermoplastic sintering of a charge at a temperature of 600 - 950 ° C is considered.
The possibility of obtaining nanofiltration membranes by applying metal oxide nanopowders on ceramic substrates with macropores is considered. As a selective layer, we chose nanopowders of titanium, aluminum, and magnesium oxides obtained by the plasma thermal method. Analysis of the initial powders, as well as the coatings after deposition, was carried out by scanning electron and atomic force microscopy. The technology of obtaining selective layers on ceramic substrates is described. A study of the characteristics of the obtained nanofiltration membranes was carried out in a laboratory setup for the desalination process.
