Crystal growth (C30)

C   Chemistry; metallurgy(315514)
C30            Crystal growth(2110)

ethod for producing europium (ii) euf2 difluoride crystals // 2627394
FIELD: chemistry.SUBSTANCE: method for producing europium (II) EuF2 difluoride crystals is carried out in two stages, at the first of which EuF3 is pre-melted and its melt is fluorinated to remove the impurity of oxygen, after cooling the melt, the fluorinated EuF3 is milled and mixed with the pre-prepared crystalline silicon powder (Si) to produce the batch of the desired composition in accordance with the equation 4EuF3+Si=4EuF2+SiF4↑. At the second stage, the produced batch is melted, homogenized and the batch melt is crystallised by directional crystallisation using a fluorine-containing atmosphere, producing single-crystal europium EuF2 difluoride boules. As a directional crystallisation method, for example, the Bridgman-Stockbarger method is used. The fluorine-containing atmosphere in the crystallisation process is created by the decomposition of ammonium hydrofluorides or alkaline-earth elements. At the first step, the silicon powder can be introduced directly into the EuF3 melt with the aid of a dispenser ensuring compliance with a predetermined relationship between EuF3 and silicon.EFFECT: increasing the yield.4 cl, 3 dwg, 1 ex

Scintillator // 2627387
FIELD: physics.SUBSTANCE: invention relates to a scintillator that can be used as an X-ray detector in medicine, when inspecting things at airports, inspecting cargo in ports, in oil prospecting. The scintillator contains a CsI crystal as its base and Tl, Bi and O, wherein the concentration a Bi with respect to Cs in the crystal is 0.001 atomic million-1 ≤a≤ 5 atomic million-1; and the ratio (a/b) of the concentration a Bi with respect to Cs in the crystal to the concentration of b O with respect to I in the crystal is of 0.005⋅10-4 to 200⋅10-4.EFFECT: scintillator has a high output at high afterglow characteristics.2 cl, 4 dwg, 1 tbl, 12 ex
ethod for growing high-temperature monocrystals by sinelnikov-dziov's method // 2626637
FIELD: chemistry.SUBSTANCE: method involves melting the initial charge in the crucible and the subsequent growth of the single crystal with a seed while cooling the melt and then cooling the grown single crystal, while the crucible is made of a refractory material with a melting point above 2300°C the formulator with convection in the bottom and discharge in the side parts of the slits, the polycrystalline material or polycrystal obtained by melting in a cold crucible or fragments of a single crystal of the corresponding oxide is used as the initial charge, and the growth of single crystals is carried out at a rate from 0.5 to 4 mm/H.EFFECT: improving the quality of grown single crystals, the variety of forms obtained while reducing material and time costs, the possibility of growing single crystals both doped and without impurities.16 cl, 9 ex

ethod of determination of conditions of crystalisation of proteins // 2626576
FIELD: chemistry.SUBSTANCE: method of crystallisation of proteins involves preparation of the initial solutions of the protein in the buffer, filtration of the resulting solution, centrifugation and filling with a solution of capillaries. The first part of the protein solutions obtained after centrifugation is mixed with the buffer solution in equal volumes, and the remaining second part is subsequently used for mixing with the precipitant. The first part of the protein solutions is analysed by small-angle of X-ray scattering to obtain a series of scattering curves, the curves are analysed and the size of a single protein subunit in each of the solutions of different concentrations is calculated. The mother liquors of the precipitant are prepared, for which substances that can influence the conformation of the molecules can be used; they filter the mother liquor of the precipitator, mix the second part of the protein solutions in equal volumes with the mother liquors of the precipitant, obtaining a collection of crystallisation solutions. Each of the solutions of the named collection is studied by small-angle of X-ray scattering in the temperature range from the temperature at which the molecule of this protein does not become denatured to 0°C with the chosen temperature change step, resulting in the graphs of the small-angle scattering curves, mathematically process these scattering curves, obtaining the distribution of the number of protein subunits and their oligomers in solution, depending on their radius, those crystallization solutions are selected, when processing the small-angle scattering curves from which the formation of the largest number of oligomers in solution was detected, which means finding conditions for crystallisation. If particles that are larger in size than the monomers are not detected in the crystallisation solutions, then step-by-step lower the temperature of the solutions under study to 0°C, at each of the stages of decreasing the temperature of the solution, each of the solutions is studied by small-angle scattering, mathematically processed by these scattering curves, obtaining the distribution of the number of particles in the solution as a function of their radius, those crystallisation solutions are selected, when processing small-angle scattering curves from which the formation of the largest number of oligomers was detected in the solution, the stepwise temperature reduction operation is completed by detecting the greatest number of oligomers, which means finding crystallisation conditions.EFFECT: invention allows to shorten the time for the formation of crystals, as well as to create a direct method for determining the formation of growth units, providing reliable and timely information about the initial stage of crystallisation of the protein.9 cl, 6 dwg
ethod for growing germanium monocrystals // 2626359
FIELD: physics.SUBSTANCE: method involves growing germanium crystals from a melt containing main dopant impurity - stibium and additional one - silicon, in an amount from 1.3⋅1020 cm-3 to 3⋅1020 cm-3 by dissolving silicon rods during the crystal growth.EFFECT: increased temperature stability of optical properties of germanium monocrystals.1 tbl

ethod of producing nanopowder of cobalt ferrite and microreactor to this end // 2625981
FIELD: technological processes.SUBSTANCE: method comprises supplying the primary components - a mixture of solutions of cobalt and iron salts in the ratio corresponding to stoichiometry CoFe2O4, and an alkali solution in proportion to the salts solutions providing acidity of the medium in the range from 7 to 8, corresponding to the conditions of coprecipitation of the components, while the solutions of the primary components are supplied in the form of thin jets with a diameter of 50 to 1000 micron at the speed of 1.5 to 20 m/s colliding in the vertical plane at the angle of 30° to 160°, at the temperature in the range of 20°C to 30°C, and a pressure close to atmospheric pressure. The usage ratio of the primary components is set in such a way that when the jets collide, a liquid fog is formed in which the solutions of the primary components are mixed and engage. The microreactor for the method comprises a housing 1 and nozzles 2 with flow diffusers 3 for supplying primary components 10 and a nozzle 4 for products removal, the microreactor housing 1 is of a cylindrical shape with a conical bottom 5, a cover 6, the nozzles 2 with flow diffusers 3 for supplying primary components 10 are made with the possibility to provide fine adjustment of the jet direction, in the cover 6 coaxially to the housing 1 a nozzle 9 is provided for supplying purging gas, and an outlet nozzle 4 is installed in the bottom 5 to remove purge gas and reaction products. The area of the outlet nozzle 4 is 20-50 times bigger than the total area of all nozzles for supplying primary components. Two or more nozzles 17 may be installed in the cylindrical part of the housing to supply a surface-active substances solution in the form of thin jets with a diameter of 10 to 1000 micron, directed to the liquid fog of the primary components engaging solutions.EFFECT: invention enables to reduce the temperature and pressure necessary to make a synthesis of oxide nanoscale cobalt ferrite particles, to reduce energy costs and ensure continuity of the process with the possibility of its implementation on an industrial scale, to reduce the cost of equipment, to increase yield and selectivity of the process, to provide optimal conditions for rapid reactions via maintenance of stable and effective hydrodynamic conditions for reagents contacting and rapid removal of reaction products.3 cl, 5 dwg, 2 ex
ethod for obtaining modified titanosilicate of pharmacosiderite type // 2625118
FIELD: chemistry.SUBSTANCE: chloride titanium-containing reagent is used in the form of titanium tetrachloride or a mixture of titanium tetrachloride and hydrogen peroxide solution in a molar ratio of 1:(8-16) and added to the silicon-containing reagent as a collective solution of sodium silicate and sodium and potassium hydroxides. The content of the components in the resulting suspension should satisfy the molar ratio TiO2:SiO2:Na2O:K2O:H2O=l:(4,3-6):(6,4-8,7):(0,8-1):(195-700). The suspension is kept in sealed conditions at a temperature of 160-180°C for 8-20 hours to form a solid phase in the form of pharmacosiderite type titanosilicate. The solid phase is separated from the mother liquor, washed with distilled water and dried. Then, the titanosilicate is modified by treatment with a solution containing hydrazine at a concentration of 0.50-1.14 g/l at T:G=1:(100-400) for 0.3-2 hours. The modified titanosilicate is separated, washed with distilled water and dried. The extraction of noble metals in mg per g of the modified product is: gold 260-275, platinum 110-134, palladium 119-141.EFFECT: method allows to obtain a monophasic hydrazinium-modified titanosilicate of the pharmacosiderite type, which has a high sorption ability with respect to noble metals.5 cl, 5 ex
ethod for producing massifs of cobalt nanowires // 2624573
FIELD: chemistry.SUBSTANCE: method involves electrodeposition of cobalt in the pores of the track-etched membranes electrolyte containing⋅ CoSO4⋅7H2O - 300-320 g/l, H3BO3 - 30-40 g/l, at pH 3.5-3.8 and temperature 40-45°C. Electrodeposition is performed using a potential sensor in the form of chloride-argentic reference electrode at a fixed distance between the cathode and the chloride-argentic reference electrode constituting 2-4 mm, and controlled by a constant voltage of 750-900 mV between them.EFFECT: improved homogeneity adjustment wires.4 ex

ethod of obtaining gallium (ii) sulfide // 2623414
FIELD: chemistry.SUBSTANCE: synthesis of GaS was carried out in a closed volume from elemental gallium and sulfur, taken in a stoichiometric ratio, under a hydrogen atmosphere at a pressure of 1300-2600 Pa, while the melt of the gallium had a temperature T(Ga)=1050-1100°C, and the sulfur melt - temperature T(S)=300-350°C.EFFECT: complete flow of the chemical reaction to form a pure single-phase product and with the possibility of scaling the process for industrial applications.1 tbl, 3 dwg
ethod of treating diamond crystals and diamond materials // 2622568
FIELD: chemistry.SUBSTANCE: method of treating diamond crystals and diamond materials by contacting in the presence of hydrogen with metallic template tool, which is capable of dissolving diamond during heating to obtain carbon. Metallic template tool is preliminary saturated with hydrogen for compact and secure storage in the template tool and extraction in the treatment zone to obtain a gaseous compound with a carbon. The treatment is carried out in a protective atmosphere at a temperature of the diamond-carbon solution in the material of the template tool and hydrogen extraction from the template tool.EFFECT: lower hazard level when using gaseous hydrogen in the technical process.6 cl
ethod of obtaining a ceramic precursor for synthesis of leukosaphir // 2622133
FIELD: chemistry.SUBSTANCE: mixture of hydrargillite with 1÷15 wt % of electrocorundum with a grain size of 10-50 mcm is filled with 0.5÷2 wt % of aqueous hydrochloric acid and stirred to form a composition of a homogeneous dispersed phase, the composition is placed in an autoclave in which hydrothermal treatment is carried out at a temperature of 180÷220°C for 4÷26 hours, the resulting mixture of formed and electrocorundum is first heated in a muffle furnace in air at a temperature of no higher than 1200°C until the moisture is completely removed, then transferred to a vacuum oven, heated and maintained at a temperature of 1700 to 1800°C for 1÷2 hours, the resulting ceramic is then cooled to form a precursor.EFFECT: invention makes it possible to produce a ceramic precursor with a high density, which makes it possible in the future to synthesise a qualitative leucosapphire with a low content of mineral impurities.5 ex

ethod of producing monocrystalline sic // 2621767
FIELD: physics.SUBSTANCE: method includes cell growth 1 of crucible 6 with SiC source 12 and docked on the lid 7 of the crucible 6 of seeding plate SiC 11 establishment of cell growth 1 through heat by heater 4, taking into account the insulating ability of thermal screen 3 necessary axial temperature distribution, secured high temperature gradients in the upper and lower zones of growth chambers and low temperature gradients in the zone of maximum heating located between the upper and lower zones, in which the growth chamber at a temperature that ensures that sublimation is a working volume of the crucible, with sublimation of spend in the crucible 6, lid 7 which is docked with the persistence of crucible on a ledge, on the inner surface of the side walls of the crucible, the height H of which exceeds the longitudinal dimension h of the working volume of the crucible and the part of the side walls above the lid 7 of the crucible 6 is located in the upper region of the growth chamber such that the end face 10 of the side wall of the crucible is placed at a temperature of 1000 to 1500°C.EFFECT: enables to increase the output of high-quality monocrystalline ingots of SiC and reduce costs.6 cl, 1 dwg, 1 tbl

ethod of forming coloured decorative coating by anodisation // 2620801
FIELD: chemistry.SUBSTANCE: method of obtaining a decorative coating with a changing colour during visual angle variation consists in the formation of one-dimensional photonic crystal with photonic bandgap in the visible range by anodising the surface of a valve metal or its alloy containing not less than 50% of valve metal at a cyclically varying parameters: current and voltage, wherein each cycle consists of two stages: anodization is carried out at the first stage at current stabilization in the range of 0.1 to 50 mA /cm2 for a time ensuring charge flow from 0.05 to 5 C/cm2; anodization is carried out at the second stage at voltage stabilization, increasing it from the voltage value at the end of the first stage to a value lying in the range from 10 to 200 V, with a decreasing voltage rise rate from 5 V/s to 0 V/s, and is held at this value for a time ensuring charge flow from 0.05 to 5 C/cm2, ensuring more than 1.4 ratio ofmaximal voltage at the second stage to minimal voltage at the first stage, wherein metal surface serves as anode during production of the decorative coating, and inert material is used as cathode, wherein anodisation charge is reduced by 0.01-10% at the first and the second stages at every next anodisation cycle, which amount lies in the range from 20 to 300.EFFECT: invention allows to obtain coloured decorative coatings of high quality using simple and reproducible method characterized by safety and environmental friendliness due to elimination of toxic substances from the technology.9 cl, 10 dwg, 2 tbl, 5 ex
ethod for contactless treatment of diamonds surface // 2620392
FIELD: chemistry.SUBSTANCE: method for contactless treatment of the diamond surface includes heating the diamond surface to a temperature just below the diamond graphitization temperature, with the subsequent contactless impact on a local diamond surface area with a point source of energy by means of which the local temperature of the diamond surface is raised above the graphitization temperature.EFFECT: method allows to obtain a diamond the surface of which will have a nanoscale relief that provides the extension of the diamond application functionalities, while increasing the process efficiency and reducing power consumption for its treatment.3 ex

ethod for producing optical polycrystalline zinc selenide // 2619321
FIELD: physics.SUBSTANCE: method involves growing zinc selenide preforms by evaporating the original powdered or compacted feedstock, condensing the vapors on the heated substrate, for which intermediate vapor condensation is carried out in the container for growing zinc selenide preforms, allowing vapor to pass through the labyrinth formed in the container working space in the form of a plate with projections, whereby the vapor passage to the substrate occurs through the non-linear winding path that facilitates the condensate purification from solid impurities, and further through the carbon graphite filter fixed between graphite rings, followed by re-deposition and transfer of steam to the substrate, wherein the vapor condensation occurrs on the substrate heated to 1030-1070°C, at the rate of 0.2-0.5 mm/h, then the grown zinc selenide preform is cooled and removed from the growth setup, it is placed into the apparatus-gasostat, and hot isostatic pressing is performed at the temperature of 1050-1150°C and the inert gas pressure of 150-200 MPa for 2-3.5 hours.EFFECT: manufacturing a monolithic preform in the form of a circular plate or a spherical concave segment of polycrystalline zinc selenide having increased chemical purity and optical uniformity of a spectral transmittance over the entire grown preform area, extended spectral transparency range with high transmittance in the visible and infrared spectrum areas in the optical parts, manufactured from these preforms.3 cl, 3 dwg, 1 tbl, 1 ex

ethod of manufacturing the epitaxial layer of silicon on a dielectric substrate // 2618279
FIELD: chemistry.SUBSTANCE: method for producing epitaxial layers of monocrystalline silicon of n- and p-type conductivity in a material of dielectric substrates with lattice parameters similar to parameters silicon by chemical vapour phase epitaxy. The substrate material may be used, in particular, leucosapphire (corundum), spinel, diamond, quartz. The method consists in the location of the substrate in the reactor, heating the working surface of the substrate to 900-1000°C, the reaction gas feed stream comprising an inert carrier gas and monosilane silicon capacity to form an initial continuous layer on the working surface of the substrate, adding to the flow of the reaction gas a halogen-containing reactant stream and forming an epitaxial silicon layer of desired thickness. Starting solid silicon layer is increased at a rate of 3000 E/min to 6000 E/min. After forming the layer on the working surface of the substrate of the reaction gas flow rate is reduced, reducing the growth rate at 500-2000 E/min. To the flow of the reaction, the gas stream of saturated vapour of silicon halide or halosilane gas is added, whose flow rate is set so that the growth rate of the silicon layer returned to the values of 3000-6000 E/min.EFFECT: obtaining high quality silicon layer and reducing the cost of the manufacturing process.3 dwg, 1 ex

Optical medium based on crystal of halide rubidium-yttrium rby2cl7, containing monovalent bismuth impurity ions, capable of broadband photoluminescence in near ir-range, and its manufacturing method // 2618276
FIELD: physics.SUBSTANCE: optical medium is proposed based on the halide crystal containing low-valency bismuth ions as the only optically active center, capable of broadband luminescence in the near IR-range, which is a crystal phase of rubidium chloride-yttrium RbY2Cl7containing isomorphic admixture of monovalent bismuth ions Bi+ in the amount of 0.1 to 1 at. %. The optical medium fluoresces in the range of 800-1100 nm, when excited by radiation with the wavelengths in the range of 570-780 nm. The process for producing the optical medium includes preparing a batch by mixing RbCl, YCl3 and BiCl3 in the molar ratio of 1:2:0.003-0.03, adding metal bismuth to the batch at the molar ratio of BiMe/BiCl3=1, placing the mixture in the quartz container in a vacuum into the vertical oven of Bridgman-Stockbarger, where the temperature in the hot zone is 620-630°C, in the cold zone - 480-500°C, and the movement speed of the container from the hot zone to the cold one is 0.2-2 mm/h to form a single-crystal sample of the optical medium. The obtained optical medium has a stable luminescence in the near IR-range, which allows its use as the active medium for the broadband amplifiers and lasers.EFFECT: method for producing a chloride crystal is fairly simple and technological and allows to grow high-quality crystals of the required size.3 cl, 3 dwg, 3 ex

ethod of applying protective coating onto quartz crucible inner surface // 2618061
FIELD: metallurgy.SUBSTANCE: by applying a protective coating on the inner surface of the quartz crucible, GeO2 is used formed by passing through a closed cold crucible of gaseous GeO, heated to 850-1,000°C, then the crucible is opened and heated under air to 850-1,000°C, then the crucible is held at the same temperature in an air atmosphere to obtain a dense coating.EFFECT: invention allows to obtain a uniform coating of germanium dioxide in the inner surface of quartz crucible with thickness to 100-150 microns using a technologically simple method not requiring significant energy expenditure.1 dwg, 1 ex
ethod for producing aluminium nitride whiskers // 2617495
FIELD: chemistry.SUBSTANCE: essence of the invention consists in treating the heated aluminium with gaseous reactants in the form of an aluminium halide, e.g. aluminium trifluoride, and a nitrogen-containing gas and the subsequent condensation of the final product, wherein the aluminium trifluoride powder is placed in one reaction chamber with the granules of metallic aluminium and simultaneously evaporated at a temperature of 1050-1150°C, and the condensation is performed on the liquid aluminium surface.EFFECT: invention allows to obtain aluminium nitride whiskers with an average diameter of less than 100 nm along the entire fiber length and the ratio of the fiber length to the diameter of more than 100.4 dwg, 2 ex
ethod for producing photosensitive chemically deposited films of lead selenide // 2617350
FIELD: chemistry.SUBSTANCE: lead selenide films are deposited on a substrate of dielectric materials from aqueous solutions containing a salt of lead (II), ethylenediamine, ammonium acetate, selenourea, ascorbic acid in an amount of 0.001-0.01 mol/l being introduced into the solution during the deposition as an antioxidant for selenourea, with the subsequent heat treatment of the deposited films in air at 503-583 K.EFFECT: increasing the photosensitivity of lead selenide films to IR-radiation, reducing the sensitizing heat treatment temperature by 90-140 K.1 tbl
Solution for hydrochemical precipitation of semiconductor films of indium selenide // 2617168
FIELD: chemistry.SUBSTANCE: invention relates to the technology of obtaining indium selenide (III), widely used in microelectronics for producing nuclear radiation detectors and creating solar radiation inverters as the basis for such material as copper diselenide (I) and indium CuInSe2. The solution for hydrochemical precipitation of a thin semiconductor film of indium selenide (III) contains an indium (III) salt, selenocarbamide, tartaric acid and sodium sulfite at the following concentrations of reagents, mol/l: indium (III) salt 0.01-0.15; selenocarbamide 0.005-0.1; tartaric acid 0.01-0.06; sodium sulfite 0.005-0.1. Due to the presence of such additives as selenocarbamide and sodium sulfite, the process kinetics and the precipitation conditions are modified in comparison with the prototype. Selenocarbamide is a source of selenide ions. Sodium sulfite acts as an antioxidant, preventing the selenocarbamide oxidation in the solution. Tartaric acid simultaneously complexes indium ions and increases the buffering capacity of the reaction mixture, maintaining the pH of the solution at a certain level.EFFECT: layers obtained from said precipitation solution have good adhesion to substrate material and a mirror surface, their thickness is equal to 300 nm.1 tbl, 2 ex
ethod of growing alloyed silicon nanocrystal whiskers // 2617166
FIELD: chemistry.SUBSTANCE: invention relates to the technology of producing semiconductor nanomaterials by growing alloyed silicon nanocrystal whiskers on silicon substrates by the scheme vapour→liquid drop→crystal (VLC). The method includes preparing a semiconductor plate by applying catalyst particles to its surface with the subsequent placement in a growth furnace, heating, deposition of crystallizable material from a gas phase containing a precursor SiCl4 and alloying compounds PCl3coming from the fluid source, and growing crystals at the initial, main, and final stages of growth. Growing the crystals is performed successively from two fluid sources. The quantitative value of the molar ratio of [PCl3]/[SiCl4], equal to m in the first source used at the initial and final stages of growth, is selected from the interval m, larger or equal to 0.01; the molar quantitative ratio of [PCl3]/[SiCl4] in the second source used at the initial stage of growth is set as m equal to 0.EFFECT: invention provides the possibility of obtaining alloyed nanocrystal whiskers of Si, having an increased level of alloying in the initial and final sections of the crystal (structure n - n-n-), and allows to create mesoscopic electrical connections conductors with linear volt-ampere characteristics.5 ex
ethod for obtaining sulfobromides of avbvicvii type // 2616929
FIELD: chemistry.SUBSTANCE: invention relates to a technology for obtaining single crystal whiskers of sulfobromides of trivalent metals SbSBr, BiSBr, CrSBr, which can be used as alloying additives in obtaining composite piezoelectric materials with specified properties in hydroacoustic transformers and transformers of electromagnetic energy into mechanical energy. SbSBr is obtained from sodium sulfide Na2S, antimony chloride SbCl3, potassium bromide KBr; BiSBr is obtained from sodium sulphide Na2S, bismuth chloride BiCl3, potassium bromide KBr; CrSBr is obtained from sodium sulphide Na2S, chromium chloride CrCl3, potassium bromide KBr; the synthesis of each desired product is carried out by the exchange interaction in the saturated hydrochloric acid solution of the corresponding metal chloride by means of dissolving in it crystalline potassium bromide and adding dropwise concentrated solution of sodium sulfide, with the subsequent treatment of the resulting reaction mixture with ultrasonic vibrations till forming a precipitate.EFFECT: increasing the desired product purity due to eliminating the oxidation of precursors and chemicals, increasing the method performance due to reducing the antimony, bismuth, and chromium sulfobromides synthesis time up to 2-5 minutes, excluding the explosion hazard due to excluding high-temperature synthesis.3 cl, 3 dwg, 1 tbl, 3 ex
ethod of growing febo3 single-crystal film on diamagnetic substrate // 2616668
FIELD: chemistry.SUBSTANCE: charge is fused in a platinum crucible, the components are taken at a ratio, wt %: Fe2O3 - 5.37, B2O3 - 51.23, PbO - 29.31, PbF2 - 13.73. Thereinafter, the crucible with the melt-solution is placed in a growth furnace, heated to 900-950°C and maintained with stirring at said temperature for a day. Then the temperature is quickly reduced to 820-830°C, the diamagnetic crystal GaBO3 is dipped into the melt-solution fixed on the chip carrier and maintained for 0.5-3 hours with stirring. Then the temperature is lowered slowly at a speed of 3-40°C/h to 800°C, and the chip carrier is removed from the furnace.EFFECT: invention allows to obtain a single-crystal film FeBO3 on the diamagnetic substrate GaBO3.3 dwg, 3 ex
ethod of forming colour centres in diamond // 2616350
FIELD: physics.SUBSTANCE: method of forming the colour centers in a diamond comprises the diamond radiation with a uniform distribution over the volume of the A-units and their concentration not less than 1018 cm-3 by ionizing radiation with the energy not less than 1 MeV with the dose of 100-120 ppm./cm2 per A-unit. Herewith the radiation is carried out repeatedly with intermediate annealing at the temperature of 850-900 K, until the desired concentration of the colour centers is achieved, and then diamond annealing is performed in the inert atmosphere at the temperature of 1200-2000 K for 0.5-2 hours.EFFECT: providing the opportunities for high concentrations of impurity-vacancy colour centers H3 and H4 with a simultaneous decrease in luminescence quenching center concentration.
ethod for producing cathode material based on system li2fesio4 // 2615697
FIELD: chemistry.SUBSTANCE: as initial component, Aerosil (SiO2) nanoscale powder with a surface area of 350-380 m2/g is selected and dried in vacuo for 1-3 hours. Iron oxide and lithium oxide films with a thickness of 1-3 nm are coated on aerosil powder by means of the MLT method to achieve the stoichiometric composition Li2FeSiO4 and the diffusion mixing of the resulting composition Li2FeSiO4 is carried out at 300°C to 500°C for 8-15 hours.EFFECT: invention allows to obtain a cathode material having a high specific surface area and high specific capacity, with the uniform distribution of the chemical composition in the total powder volume and the defect-free crystal structure.1 tbl
aterial for dichroic light polarization - crystal liba12 (bo3)7f4 // 2615691
FIELD: physics.SUBSTANCE: invention relates to the materials for the polarization optical devices that can be used to obtain linear-polarized light in the optic-electronic devices: polarimeters, ellipsometers, dichrometers, photoelectric autocollimators, modulators of light fluxes, devices of indicating, displaying and storing information, memory elements. Crystal LiBa12(BO3)7F4, characterized by the presence of the selective absorption effect - the dichroism effect in the visible spectrum area, is grown from the solution-melt of the primary components in the ratio of 0.30 BaCO3 : 0.30 BaF2 : 0.30 H3BO3 : 0.10 Li2CO3 on seeded growth by reducing the solution-melt temperature of 910°C to 888°C at the temperature lowering speed of 1.2-1.5°C/day and one-sided crystal rotation at the rate of 1.0-2.0 rpm.EFFECT: obtaining effective medium for linear dichroic polarization, the optical quality of which provides manufacturing the plates providing reception of the polarized light in the visible spectrum area.4 dwg, 1 ex
Czochralski's method of growing paratellurite monocrystals from liquid melt // 2614703
FIELD: chemistry.SUBSTANCE: growing is carried out from a fixed crucible with programming the seeding pulling and rotation speeds, wherein, after reaching the desired diameter, pulling the cylindrical part is conducted at rotation speeds the values of which correspond to Reynolds numbers 100-150. In said mode, a system of two opposite convective supercooled melt cells orbiting the crystal, of a darker colour than the rest of the surface, is formed on the melt surface. Thereinafter, with a period of 600-800, the reversible rotation direction of the seeding with the crystal is changed to the contrary during the entire pulling time. The uniform rotation speed reduction, the rotation direction switching, as well as the uniform increase in the rotation speed to the previous absolute value, are carried out for a time of 200-240 c. Reversive rotation results in periodic destruction of the melt stagnation area under the central - paraxial - part of the growing crystal surface, which provides a more uniform distribution of impurities and other structural defects along the crystal radius.EFFECT: improved structural perfection and uniformity of paratellurite single crystals and the elements of optical and acousto-optic devices made thereof.2 dwg, 2 ex

ethod for producing thin nanodiamond film on glass substrate // 2614330
FIELD: chemistry.SUBSTANCE: thin nanodiamond film is obtained on a glass substrate by spraying the target material by a pulsed laser in a vacuum. The target is represented by detonation nanodiamond tablets, and the pulsed laser radiation source is represented by the laser with a wavelength of 1064 nm of a series of 13 to 20 pulses, with a pulse energy from 3.8 to 5.8 J and a duration from 1 to 1.5 ms. The process is accompanied by dispersing the detonation nanodiamond conglomerates up to individual nanocrystals and purification from impurities in the process of high-energy laser pulse impact. The resulting film is a two-dimensional polycrystalline nanodiamond aggregate.EFFECT: obtaining thin-film hardening coatings and creating nanostructured materials.9 dwg, 2 tbl, 5 ex

ethod for producing alloyed yttrium aluminium garnet // 2613994
FIELD: chemistry.SUBSTANCE: method is performed by dispersing the solid aluminium yttrium oxide derivative in nitrate aqueous solutions of alloying elements salts, and the subsequent treatment with the final product extraction. Wherein the initial yttrium aluminium derivative is represented by the product previously obtained by co-precipitation of aluminium and yttrium from the nitrate aqueous solutions. The resulting precipitation product is afterwards subjected to filtration and washing with deionized water. Thereafter, the extracted product is dispersed by the ultrasonic influence in the solution of the alloying elements selected from the group of alkali and alkaline earth metals and the elements of the 3d group, the resulting pulp is dried with constant stirring, the dried product is ground and calcined at 1200°C to 1600°C.EFFECT: invention allows to obtain yttrium aluminium garnet with the uniform distribution of alloying elements.3 cl, 4 dwg, 3 tbl, 4 ex
Polycrystalline synthetic jewelry material (versions) and method of its production // 2613520
FIELD: chemistry.SUBSTANCE: creating a polycrystalline jewelry material from coloured transparent or translucent oxide ceramics with dopants is proposed. The material consists of oxidic compounds which are represented by yttrium-aluminium garnet or magnesium aluminium spinel, for dying which ions of transition and rare earth metals: zinc, iron, vanadium, chromium, manganese, nickel, cobalt, titanium, neodymium, europium, terbium, ytterbium, holmium, erbium, thulium - are used. The method of manufacturing transparent or translucent ceramic comprises the stages of obtaining a powder mixture and annealing the components, hot uniaxial/cold isostatic pressing, hot isostatic pressing and heat treatment.EFFECT: wider colour range of samples and possibility of obtaining colour effects caused by the activator concentration variable as per the pattern or the crystalline phases are achieved, the cost of goods is much less in comparison with the use of single-crystal material.5 cl, 4 tbl, 2 ex
Inorganic single-crystal scintillator // 2613057
FIELD: chemistry.SUBSTANCE: invention relates to novel crystalline inorganic scintillation materials based on lanthanum bromide alloyed with cerium, and can be used for registration of ionizing radiation - gamma rays, X-rays, cosmic rays, elementary particles in fundamental physics, engineering and medicine. The inorganic single-crystal scintillator has the composition of La(1-m)CemBr(3-2k)Ok, where m is the mole fraction of cerium replacing La, more than 0, but less than or equal to 1; k - the mole fraction of oxygen replacing bromine, within the range from 1.5⋅10-4 to 8⋅10-4.EFFECT: increased mechanical strength of the crystal scintillator, in particular with a diameter of 15 mm and more, while preserving the high scintillation performances.1 tbl, 8 ex
ethod of producing copper-containing nano-catalysts with developed surface // 2611620
FIELD: technological processes.SUBSTANCE: invention relates to a method of producing copper-containing nano-catalysts with developed surface, which involves, that first from an electrolyte solution onto a metal carrier by electrodeposition copper is applied, then the carrier with the applied active metal is subjected to thermal processing. Electrodeposition process is performed in such a way, for to grow on a metal substrate with a heat conductivity coefficient less than 20 W/(m⋅K) a monolayer of icosahedral small particles of copper with micron sizes from 5 to 15 mcm and having 6 axes of symmetry of the 5th order, or layers of microcrystals with disclination type defects in the crystal lattice, then they are annealed in air atmosphere at the temperature of 300–400 °C and maintained for 4 hours till the small particles form a developed surface in the form of nanowhiskers or at the temperatures of 500–600 °C and maintained for 2–3 hours till the small particles form a developed surface in the form of nanopores, or inner cavities, or a corrugated relief.EFFECT: technical result is producing a nano-catalyst with high specific surface, good adhesion to a carrier, high mechanical strength and low hydrodynamic resistance.3 cl, 8 dwg

ethod for applying mark onto surface of diamond or cut diamond to determine its authenticity // 2611232
FIELD: security.SUBSTANCE: invention relates to a method of authenticating an article in the form of a diamond or a cut diamond. Identification mark invisible with the naked eye is applied onto a diamond or a cut diamond by exposure to a laser radiation with a wavelength exceeding 500 nm with simultaneous affecting by ultrasound using a tool located on the section surface. After that saved are at least two interference images of the article identification mark by means of a probing radiation with waves of different lengths together with data on location of a certain section of the article and an angle of incidence of the probing radiation. Determination of authenticity and correspondence to the saved values is carried out by directing the probing radiation onto the said section to create at least two interference images of the identification mark, which then are compared with the saved interference images, matching of which denotes the mark authenticity.EFFECT: technical result is ensuring uniqueness of the mark, protection from counterfeiting and reliable identification during authentication.4 cl, 2 dwg, 2 ex

ethod of impact compression of bodies with low density, apparatus and reactor for realising said method // 2610865
FIELD: physics.SUBSTANCE: invention relates to the field of high dynamic pressures and temperatures generation and may be used for chemical reactions, changes in the crystal structure of solids under high pressure and temperature, in particular for producing artificial diamonds (diamond powder), to compress the DT-ice to obtain a neutron source for inertial confinement fusion. The appartus for impact compression process of low density bodies contains the appartus shell 2 and a compressible body 1, installed at the front part of the apparatus shell. The hollow cylinder 5 can be mounted at the apparatus shell, the tail of which may joins a thin-walled hollow cylinder 7 with bar 9. The reactor for the execution of low density bodies impact compression consists of the reactor chamber and two accelerating devices for the apparatuses (cannons), looking toward each other. Inside the reactor chamber a porous layer of a porous metal is installed . The foam metal , tightly packed layer of thin-walled metal tubes, thin-walled boxes layers or cells can be used instead of a porous metal. The summary of the impact compression process of low-density bodies consists of axial compression of each compressed body by solid rear portion of the apparatus shell at frontal collision of two identical apparatuses in the reactor chamber. Thus, there is also impact compression by impact wave and the interference can be used, as well as focusing of reflected from the compressed bodies separation borders and apparatus shells of the impact waves. Also it can be carried out the radial compression of compressible bodies, converging towards the axis of apparatuses by circular liquid or plasma flow, obtained as a result of collision of two hollow cylinders. The interference of two impact waves can be used, resulting from the impact of bars at rear parts of the apparatus shells.EFFECT: invention allows to increase the final compression , pressure and temperature ratio, while the dynamic compression of low density bodies.13 cl, 17 dwg
ethod of producing crystals of thallium halide // 2610501
FIELD: technological processes.SUBSTANCE: invention relates to the production of materials, which are transparent in the infrared spectral region that can be used for manufacturing optical elements, that are transparent in the wavelength range from 0.4 to 25 microns; production of uncooled detectors c- and g-radiation for nuclear physics methods of diagnosis and monitoring, as well as the manufacture of optical fibers IR. A process for producing crystals of thallium halide for the infrared optics involves the synthesis of thallium halide reacting molten metal thallium, taken in excess, with the pairs of halogen in a vacuum, at a temperature at 10-30°C below the melting temperature of the resulting halide of thallium, which is carried out in a horizontally mounted container, made in two containers connected by a constriction of the hollow axis and rotating around its longitudinal axis at a speed of 120-150 rev/min, the separation of the excess metal from the ingot synthesized thallium halide, thallium halide purification obtained by vacuum distillation and melt crystallization directly followed by growing crystal.EFFECT: simplification of the process of crystal growth, and improvement of their optical quality.2 dwg, 2 ex

Device for preparation of single crystals of high-melting fluorides // 2608891
FIELD: chemistry.SUBSTANCE: invention relates to devices for preparation of single crystals of high-melting fluorides of horizontal directional crystallization from melt. Device comprises vacuum chamber 1 accommodating heat unit 2, consisting of coal-graphite heat-insulating modules 3, top 4 and bottom 5 heaters and heat shields 15, graphite container 6 with charge of material to be crystallised, installed with possibility of moving into a vacuum chamber 1, inert gas supply nozzles 10 and evacuation system and/or pumping of gaseous products 9, inspection window 11, wherein upper flat belt L-shaped heater 4 and bottom belt U-shaped heater of inverted shape 5 are made in form of graphite mono-blocks integrated with buses, on one side fixed with water-cooled current leads of vacuum chamber by means of detachable connection.EFFECT: simplified and improved manufacturability and reliability of heating assembly, including by eliminating effect of thermal expansions on heaters.3 cl, 2 dwg
ethod for synthesis of semiconductor nanoparticles // 2607405
FIELD: chemistry.SUBSTANCE: invention relates to colloidal chemistry and nanotechnology. Method comprises synthesis of nanocrystals of precursors containing chalcogen and a group II or IV metal, in presence of a solvent at room temperature using a "double drop method", for which said precursors are introduced simultaneously in droplets while stirring. Solvent used is an ionic liquid or a mixture of ionic liquids combined with one or more low-boiling organic solvents. Reaction mixture containing a nucleus of semiconductor quantum dots is exposed to UV light and treated with ultrasound. Nanoparticles of group II or IV metal chalcogenides are obtained with dispersion medium size of not more than 10 %, having high photostability and aggregative stability, capable of being dispersed in both polar and nonpolar solvents without additional treatment steps. Toxic solvents are not used during synthesis.EFFECT: invention can be used in production of luminescent materials, superminiature light-emitting diodes, white light sources, including transistors, nonlinear optical devices, photosensitive and photovoltaic devices.1 cl, 8 dwg, 11 ex

Complex lithium-lanthanum hafnate as luminescent material for conversion of monochromatic laser radiation and method for production thereof // 2606229
FIELD: chemistry.SUBSTANCE: invention relates to novel compounds of sensitised phosphors based on inorganic crystalline compounds, specifically to complex lithium-lanthanum hafnate composition Li7La3-x-y-z-nNdxHoyErzDynHf2O12, where x=2.5⋅10-2-1⋅10-1, y=1.6⋅10-7-4.7⋅10-7, z=1.5⋅10-6, n=1.2⋅10-6-4.7⋅10-6. Also disclosed is a method for production thereof.EFFECT: obtained composition is used as luminescent material for conversion of monochromatic laser radiation at wave length 808 nm into a series of emission lines 2–2,3 mcm, 2,5–2,9 mcm, 3,1–3,35 mcm.2 cl, 3 dwg, 3 ex

ethod of producing monocrystalline sic // 2603159
FIELD: chemistry.SUBSTANCE: invention relates to technology of producing monocrystalline SiC - wide-band gap semiconductor material, used for making integrated microcircuits. Method involves sublimation of SiC source 6 on inoculating plate 5 of monocrystalline SiC, fixed on cover 3 of a growth cell inside a cylindrical channel, formed in a growth cell, when source of SiC 6 is placed in cavity, formed by walls of growth cell, cylindrical channel and bottom 4 of growth cell, and passage of vapour phase of SiC source through wall of cylindrical channel, wherein growth cell is made of multiple, arranged in series one above another, sections 1 for arrangement of SiC source 6 and section 2 for forming ingot of monocrystalline SiC, in form of hollow graphite cylinder, on which there is cover 3 of growth cell with inoculating plate 5 of monocrystalline SiC, and each of sections 2 for arrangement of SiC source 6 is composed of two cylinders, located coaxially one inside another with radial clearance, inside of which lower edges of cylinders are tightly connected to bottom to form circular chamber for placement of SiC source 6 and inner cylindrical channel of section, wherein height of outer cylinder exceeds height of inner cylinder, and cylindrical channel of growth cell is formed, coaxially in series while placing section 1 for placement of SiC source 6 and section 2 for forming ingot of monocrystalline SiC 4 at bottom of growth cell. Furthermore, costs of carrying out method are reduced due to possibility of repeated use of growth cell by replacing separate degraded sections of growth cell with new ones.EFFECT: invention increases growth rate of ingot of monocrystalline SiC without deterioration of quality, which increases output of ingots of monocrystalline SiC per unit time.1 cl, 2 dwg, 1 tbl

ethod of producing vanadium dioxide nanoparticles // 2602896
FIELD: chemistry.SUBSTANCE: invention can be used in making thermochromic material, cathode material for lithium current sources, thermistors, thermal relays, switching elements. To obtain vanadium dioxide nanoparticles of monoclinic crystal system, method includes hydrothermal treatment of a mixture of ammonium metavanadate NH4VO3 and an organic acid and subsequent annealing of obtained product in a vacuum or inert atmosphere. Organic acid used is citric acid. Hydrothermal treatment is carried out at pH 4.0-5.5 and temperature of 180-220 °C for 2-20 minutes. Annealing of product is performed at temperature 350-370 °C for 5-60 minutes.EFFECT: invention enables to lower temperature and duration in production of vanadium dioxide of monoclinic crystal system, obtain particles with morphology of corrugated nanoplates.1 cl, 2 dwg, 4 ex

ethod of obtaining epitaxial layers of cdxhg(1-x)te of p-type of conductivity // 2602123
FIELD: electricity.SUBSTANCE: invention relates to materials of electronic equipment, namely to methods of obtaining epitaxial layers of semiconductor solid solutions of CdxHg1-xTe for making on their basis photovoltaic infrared radiation receivers. Method of obtaining epitaxial layers of CdxHg1-xTe of p-type conductivity involves growing an epitaxial layer of CdxHg1-xTe with a chemical composition within the range from x=0.19 to x=0.33 of molar ratio of cadmium telluride by liquid-phase epitaxy in a sealed quartz ampoule from a melt-solution based on tellurium at the temperature of 500÷515 °C and in situ annealing the epitaxial layer in vapors of charge, from which it was grown, first at the temperature of 350÷370 °C during 1÷2 hours, and then at the temperature of 200÷240 °C during 20÷24 hours. Technical result of the invention is reproducible obtaining the epitaxial layers of CdxHg1-xTe of p-type of conductivity with the concentration of charge carriers of (0.5÷2.0)×1016 cm-3 at 77K with high values of mobility of the charge carriers and uniform distribution of electrophysical characteristics throughout the thickness of the epitaxial layer, as well as reduced time for production of the epitaxial layers.EFFECT: proposed is a method of obtaining epitaxial layers of semiconductor solid solutions of CdxHg1-xTe for making on their basis photovoltaic infrared radiation receivers.1 cl, 1 tbl

ethod for growing monocrystals of substances with density exceeding density of their melt // 2600381
FIELD: manufacturing technology.SUBSTANCE: invention relates to growing monocrystals from a liquid melt using Czochralski's method. Growing a crystal with radius r is first performed using the Czochralski's method by drawing from fixed pot with radius R1, so that where ρhd - density of the crystal, ρl - is density of the melt. Produced crystal is tore off the melt and cooled to room temperature in a growth chamber. Then, the growth chamber is opened, the pot is removed from the heater replaced with a pot of smaller radius R2, such that thereafter the chamber is closed, temperature is raised to melting point, crystal is lowered to contact with the melt and the crystal is again grown by its permanent downward movement.EFFECT: technical result is improved structural perfection of grown crystals due to reduction of residual mechanical stresses and reduction of density of dislocations.1 cl, 6 dwg, 2 ex

Germanium monocrystals-based method for producing shaped articles // 2600380
FIELD: optics.SUBSTANCE: invention relates to technology of producing optical articles made from germanium by growing germanium monocrystals from the melt in the form of shaped articles in the form of convex-concave pieces, which can be used after processing for making the lenses of the infrared range. Germanium monocrystals are grown on the inoculating crystal using a vertical shaping element 1 placed into crucible 2, having holes 6 in the point where its lower part adjoins crucible 2 to remove the excess melt formed during germanium crystallization, horizontal upper and lower shaping elements are placed in the grooves of vertical shaping element 1 with diameter d, said upper and lower shaping elements have central holes, elements 3 of convex-concave shape with diameters, d1 and d2, respectively, at that, d2> d1> d. Grown monocrystal is shaped as a lens piece due to shaping elements.EFFECT: invention enables serial producing germanium monocrystals (including large-sized ones) with different section shape with minimum material consumption.1 cl, 1 dwg, 2 ex

Optical medium based on cadmium-caesium halide crystal cscdbr3, containing impurity of univalent bismuth ions capable of broadband photoluminescence in near infrared range, and production method thereof (versions) // 2600359
FIELD: chemistry.SUBSTANCE: invention relates to optical media based on crystalline halides and can be used in optical communication systems as broadband amplifiers and lasers. Optical medium contains low-valent bismuth ions as only optically active centre, is capable of broadband luminescence in near infrared range, is a crystalline phase of caesiu-cadmium bromide CsCdBr3, containing an isomorphic admixture of univalent bismuth ions Bi+ in amount of 0.1 atm% to 3 atm%, and luminesces in range of 900-1,200 nm when excited with radiation with wavelength in range of 570-700 nm. Disclosed are two versions of a method of producing an optical medium. First version involves preparation of charge by mixing CsBr, CdBr2 and BiBr3 or CsCdBr3, CdBr2 and BiBr3, adding to charge bismuth metal, heating obtained mixture placed in a quartz container, in a vacuum to temperature of 450-500 °C until complete melting, slow cooling of melt to spontaneous crystallisation and separation of monocrystals from produced polycrystalline structure. Second version involves preparation of charge by mixing CsBr, CdBr2 and BiBr3 or CsCdBr3, CdBr2 and BiBr3, adding to charge bismuth metal, placing mixture in a quartz container in a vertical Bridgman-Stockbarger furnace until formation of a monocrystalline sample of optical medium. Disclosed optical medium is not hygroscopic, possesses stable luminescence in near infrared range, specifically in range of 900-1,200 nm when excited with radiation with wavelength in range of 570-700 nm.EFFECT: method of producing bromide CsCdBr3 is quite simple technologically and enables to grow quality crystals of required dimensions.4 cl, 2 dwg, 4 ex

ethod and device for refining technical silicon // 2600055
FIELD: technological processes.SUBSTANCE: invention relates to production of technical silicium in ore-thermal furnaces and its further refinement. Method of refining technical silicon is implemented by directed crystallization, herewith the silicon melt is cooled down to 1,420 °C, immersed for 3-30 sec with metal crystallizing molds with the initial temperature of approximately 150-200 °C, impurities of metals in form of intermetallic compounds and solid solutions with silicon are extracted on the molds surfaces, after which the molds together with the impurities are removed from the melt and moved into a superheated flux for draining of silicon enriched with the impurities. Molds are made in the form of solids of revolution - balls, cones or cylinders. Device for implementation of this method comprises a mass exchanger with molten silicon and a settler with overheated flux for accumulation of silicon with increased content of impurities. Solids of revolution can be equipped with pins to increase the surfaces of crystallization.EFFECT: invention ensures production of high-quality and cheap raw material with low content of impurities for further mass production of ultrapure silicon (SoG-Si).3 cl, 2 dwg

Device for growing monocrystals of fluorides and synthesis method thereof // 2599672
FIELD: chemistry.SUBSTANCE: invention relates to production of monocrystals of fluorides from melt for use in optics. Device for growing monocrystals of fluorides 10 from melt 9 by drawing down comprises crucible-heater 5 made from graphite in form of vertically installed hollow thin-walled cylinder, equipped in lower part with cover 6 made from graphite with a hole of an arbitrary shape, repeating required section of grown crystal 10, wherein cross section of hole in cover is not more than 1.5 mm, its length is 0.1-1.0 mm, cover 6 is detachable with possibility of repeated mounting-dismantling and crucible-heater 5 is equipped with electric lines 7, 8, made of refractory material, for example graphite.EFFECT: invention enables to grow monocrystals of fluorides of high optical quality in form of fibres and rods with rectangular or round section with typical dimensions from 0,2 to 1,5 mm.1 cl, 7 dwg
ethod of alloying silicon // 2597389
FIELD: chemistry.SUBSTANCE: invention relates to equipment, related to processes of ion-plasma alloying of semiconductors and can be used in making solar cells, semiconductor instruments and integrated microcircuits based on silicon. Doping technique of silicon consists in that silicon plate is treated in glow discharge of inert gases, non-doped dopant source used is heavily doped electrode in form of plate made of heterogeneous silicon alloy with phosphorus or boron, and alloying is carried out at alternate polarity of voltage pulses supplied to electrodes. Plasma alloying can be carried out without special safety measures and exclusion of expensive highly toxic fire and explosion hazardous gases, which simplifies process and reduces costs. Before ion-plasma treatment resistance silicon plate resistance is equal to 10 Ohm, after processing it decreases to 3 Ohm that testifies to improvement of technical and economic parameters of silicon alloying.EFFECT: alloying.1 cl
ethod for production of solid disperse system with silicon dioxide // 2595846
FIELD: pharmaceutics.SUBSTANCE: invention relates to medicinal agents, concerns preparation of dosage forms on basis of silicon dioxide. Task is solved by that mixer is filled mesoporous silicon dioxide, feeding into reactor an absorbable solution or melt of medicinal and auxiliary substances and intensely stirring for 5-7 minutes. Bulk product is formed with virtually 100 % yield and absence of losses. Flow rate of initial powder, as well as their compositions with auxiliary substances are assessed by rate of precipitation of powder or granules using a vibration funnel of serial device VP-12A with diameter of outlet hole 12 mm.EFFECT: frequency and amplitude of vibration of vibration funnel is 50 Hz and 0, 08 mm, respectively.1 cl, 5 ex, 2 tbl

ethod of producing wollastonite // 2595682
FIELD: chemistry.SUBSTANCE: invention relates to processing of calcium- and silicon-containing industrial wastes from boron production (borogypsum) and can be used in production of needle wollastonite for use in non-ferrous metallurgy, in tyre, asbestos-cement and paint industry, in production of ceramics. Wollastonite is produced by hydrothermal action on calcium- and silica-containing technogenic raw material with alkali metal hydroxide, followed by separation, drying and thermal treatment of formed precipitate with calcium hydromonosilicate, wherein calcium- and silica-containing material used is borogypsum, alkali metal hydroxide is added in stoichiometric amount based on reaction equation of formation of calcium hydromonosilicate in concentration, providing ratio of solid and liquid phases S:L=1:(7-10), wherein reaction is carried out in an autoclave at temperature of 210-225 °C and pressure of 20-23 atm, separated calcium hydromonosilicate is washed with water at 60-70 °C and dried at 80-90 °C for 4 hours, thermal treatment is carried out at 850-1,000 °C for 1-2 hours.EFFECT: technical result is simplification and high environmental safety of method with simultaneous reduction of cost due to minimisation of labour input and costs for preparation of initial components.1 cl, 8 dwg, 2 ex
 
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