Method of production of graphene structures
SUBSTANCE: invention relates to nanotechnology. The graphene structures in the form of flat carbon particles with the surface of up to 5 mm2 are obtained by burning in air atmosphere or inert gas of composite press material produced from micro- and nanodisperse powders of active metals such as aluminium, titanium, zirconium, nanodisperse powders of silicon or aluminium borides taken in an amount of 10-35 wt %, and fluoropolymers such as polytetrafluoroethylene or a copolymer of tetrafluoroethylene and vinylidene fluoride, taken in amount of 90-65 wt %.
EFFECT: increased yield of graphene.
3 tbl, 4 dwg, 5 ex
The present invention relates to a technology for graphene, which find their application in various industries.
From the scientific and patent literature there are many different ways to obtain graphene.
There is a method of producing graphene by mechanical exfoliation, which with the help of adhesive tape from graphite tear layer graphene, while having a relatively large samples of graphene size ~10 μm, suitable for electrical and optical measurements. After peeling the adhesive tape with a thin film of graphite and graphene pressed against the substrate oxidized silicon. In this way it is difficult to obtain a film of a certain size and shape in fixed parts of the substrate (horizontal sizes of the films are usually about 10 μm) (Novoselov .S. et al. "Electric Field Effect in Atomically Thin Carbon Films", Science v.306, p.666, 2004; J. S. Bunch et. al. "Electromechanical Resonators from Graphene Sheets". Science, v. 315, p.490, 2007).
The described method of producing graphene, which consists in the fact that the oxidized silicon substrate covered with epoxy glue (I used a glue layer thickness of ~10 µm) and thin plate of graphite press to glue with the help of the press. After removal of the graphite plate with a piece of adhesive tape on the surface remain the region with graphene and graphite (E. Rollings et. al. "Synthesis and characterization of atomically thin graphite films on a silicon carbide substrate" J. Phys. Chem. Solids, v. 67, p.2172, 2006; J. Has et. al. Highly ordered graphene for two dimensional electronics Appl. Phys. Lett. v.89, p.143106, 2006).
U.S. patent No. 8,287,699 (IPC B01J 19/10, 2012) a secure method of obtaining nanographene materials by dispersion in a liquid medium graphite material with subsequent treatment of the suspension with ultrasound of high intensity and duration, while the plates are formed of graphene.
The article (Novoselov .S. et al. "Two-dimensional gas of massless Dirac fermions in graphene", Nature v.438, p.197, 2005) describes a method of printing graphene electrical circuits. The printing process consists of sequential transfer from the substrate Si/SiO2gold contacts, graphene and, finally, a dielectric polymethylmethacrylate (emission spectra obtained for pure) with a metal gate on a transparent substrate made of polyethylene terephthalate (PET), pre-heated above the temperature of its softening to 170°C, so the contacts are pressed into the PET, and graphene gets good contact with the substrate material. This method is suitable for application of graphene on any substrate that is suitable, in particular, for optical measurements.
In the works (Zhang Y. et. al. "Experimental observation of the quantum Hall effect and Berry''s phase in graphene" Nature, v. 438, p.201, 2005; Sandip Niyogi, Elena Bekyarova et al. "Solution Properties of Graphite and Graphene" J. Am. Chem. Soc.; 2006; 128(24) pp 7720; (Communication); Bunch J.S. et al. "Coulomb Oscillations and Hall Effect in Quasi-2D Graphite Quantum Dots" Nano Lett. 5, 287, 2005) describes chemical methods to obtain graphene, which distinguish the I large percentage yield of the material, but the small size of the films is ~10-100 nm. The microcrystals of graphite exposed to a mixture of sulfuric and hydrochloric acids. Graphite is oxidized, and at the edges of the sample appear carboxyl groups of the graphene. Turn into chlorides using thionyl chloride. Then under the action of octadecylamine in solutions of tetrahydrofuran, carbon tetrachloride and dichloroethane they move in graphene layers with a thickness of 0.54 nm. Known RF plasma-chemical method for the deposition of graphene from the gas phase (Wang J.J. et. al. "Free-standing subnanometer graphite sheets" Appl. Phys. Lett, v.85, p.1265 (2004) and the method of growing films of graphene at high pressure and temperature (Parvizi F., et. al. "Graphene Synthesis via the High Pressure - High Temperature Growth Process" Micro Nano Lett., v.3, p.29, 2008).
In patents (US No. 2012/0082787, IPC B05D 3/02, C23C 16/28, 2012 and US No. 8,227,069, IPC B32B 3/00, B32B 5/00, 2012) describes the obtaining of graphene grown on substrates of silicon carbide SiC. Graphite film is formed by thermal decomposition of the surface of the SiC substrate at temperatures up to 1350°C in a vacuum of 1-10-4mm Hg or in a current of inert gas.
As follows from the analysis of scientific literature and patent data described methods for producing graphene technologically quite complex, high labour intensity, the area of the formed particles of graphene is small and is measured in square microns.
The task of the invention is the development of new STRs is both produce graphene structures providing education graphene particles with the surface to 5 mm2, a large output and allows you to produce graphene in large quantities (up to 50 g/day on the installation volume of the Cabinet-reactor 10 l).
The problem is solved by the fact that developed a new method to produce graphene structures in the form of a flat carbon particles with the surface to 5 mm2consists in the fact that graphene is produced by combustion of composite moulding material obtained from powders of fluoropolymers, such as polytetrafluoroethylene and a copolymer of tetrafluoroethylene and vinylidenefluoride, and micro - and nano-powders of active metals such as aluminum, titanium, zirconium, nanosized powders of silicon and aluminum borides with a ratio of metal : fluoropolymer = 10-35 : 90-65%.
During the research work it was found that interaction of nano-dispersed powder aluminum with Teflon along with aluminum TRIFLUORIDE is formed flat flakes of carbon from the surface to 5 mm2.
4Al+3(-C2F4-)n→6C+4AlF3, ∆ H0=-3612,76 kJ
When ignited stoichiometric powder mixture of nanosized aluminum and copolymer of tetrafluoroethylene and vinylidenefluoride the flame of a gas burner, instant ignition and combustion of the mixture, followed by C is the uke cotton and the formation of smoke, fine particles of carbon.
When ignited extruded composite gas burner with blowing air (flame temperature of about 900-1000°C) for two to three seconds starts turbulent combustion with combustion of the sample within 2-4 C. this produces a large number of flat large flocculent particles of soot that are easy glomerida. In addition, the observed and the formation of filamentous and elongated funnel of soot formation in length up to 5 mm
Like this reaction proceeds in an atmosphere of argon when ignited extruded composite is heated nichrome wire with education such as flat particles.
Investigation of planar carbon particles by scanning electron microscopy and x-ray diffractometry showed that they consist of two-dimensional structures, typical for graphene (hexagonal crystalline phase, the maximum x-ray at 2Θ=20,61°).
Similar to the formation of graphene obtained by interaction of composite materials on the basis of micron and nano-sized powders of active metals such as aluminum, titanium, zirconium, nanosized powders of silicon and aluminum borides and fluoropolymers such as polytetrafluoroethylene and a copolymer of tetrafluoroethylene and vinylidenefluoride.
The composites obtained by mixing powders of metals and fluoropolymers with a ratio of metal : fluorine is OLIMAR = 10-35 : 90-65%, followed by compressing the mixture in the mold at a pressure of 150 to 180 kg/cm 2and the temperature of 150-190°C. To increase the efficiency of contact of the reactants in the composite material mixture is prepared by mixing the components in a planetary mill. If soluble in the solvents of the fluoropolymer composite material is prepared by mixing metal powder with a solution of fluoropolymer with vigorous stirring, followed by evaporation of the solvent and grinding residue.
The invention is illustrated by the following examples.
Charged to the reactor 2.9 g of powder of nano-aluminum (average particle diameter 200 nm) and a solution of 9.5 g of PTFE f-42 (h-A/FP) in 150 ml of acetone, the mixture is intensively stirred, you get a suspension, which is then poured into the mold, the layer height of the suspension is 6-8 mm, After which the acetone is evaporated and get the film composite thickness of 0.5-2 mm, which is ground to a powder, sieved through a sieve with mesh size 0.25 mm Sieved powder is placed in a mold and heated at a temperature of 160-165°C for 30 minutes, then heated, the powder is pressed at a pressure of 150 kg/cm2. Get a tablet with a diameter of 40 mm and thickness of 5 mm, which is placed on the stand in a sealed box and ignited by the flame of a gas burner with blowing air. Duration of burning tablets is not more than 2 Sekou is d, resulting in a cloud of carbon particles. Particles are deposited on the pallet, from which they are transferred into the container. From 5 g of pressed composite obtained 0.5 g of carbon particles with a graphene structure (56,8% of theory).
3.0 g of aluminium powder brand ASD-4 (average particle size 3.5 microns) and 9.5 g of powder of PTFE f-42 mixed in a planetary mill. Part of the obtained powder is placed in a mold and heated at a temperature of 160-165°C for 30 minutes, then heated, the powder is pressed at a pressure of 150 kg/cm2. Get a tablet with a diameter of 40 mm and thickness of 5 mm, a Pill wrapped with a nichrome wire, the ends of which lead to the source of electric current, then placed on the stand in a Cabinet with a sealed door, which was rinsed with argon, the wire serves the voltage at this tablet flashes and lights up. As a result of burning pills, the duration of which is not more than 1 second, it forms a cloud of carbon particles. Particles are deposited on the pallet, from which they are transferred into the container. From 5 g of pressed composite obtained 0.45 g of carbon particles with a graphene structure (54.8% of theory).
Charged to the reactor 3.0 g of nanosized silicon powder (average particle size 35 nm) and a solution of 12.0 g of PTFE f-42 B in 150 ml of acetone, the mixture intensive what about the mix, you get a suspension, which is then poured into the mold, the layer height of the suspension is 6-8 mm, After which the acetone is evaporated and get the film composite thickness of 0.5-2 mm, which is ground to a powder, sieved through a sieve with a mesh size of 0.25 mm Sieved powder is placed in a mold and heated at a temperature of 160-165°C for 30 minutes, then heated, the powder is pressed at a pressure of 150 kg/cm2. Get a tablet with a diameter of 40 mm and thickness of 5 mm, which is placed on the stand in the box and ignited by the flame of a gas burner with blowing air. Duration of burning tablets is not more than 3 seconds, resulting in a cloud of carbon particles. Particles are deposited on the pallet, from which they are transferred into the container. From 5 g of pressed composite obtained 0.40 g of carbon particles with a graphene structure (45,9% of theory).
Charged to the reactor 6.6 g of nanosized titanium powder (average particle size 40 nm) and a solution of 13.4 g of PTFE f-42 B in 150 ml of acetone, the mixture is intensively stirred, you get a suspension, which is then poured into the mold, the layer height of the suspension is 6-8 mm, After which the acetone is evaporated and get the film composite thickness of 0.5-2 mm, which is ground to a powder, sieved through a sieve with mesh size of 0.5 mm The sifted powder is placed in a mold and heated at a temperature of 160-165°C for 30 minutes, then heated, the powder is pressed at a pressure of 150 kg/cm2. Get a tablet with a diameter of 40 mm and thickness of 5 mm, which is placed on the stand in the box and ignited by the flame of a gas burner with blowing air. Duration of burning tablets is not more than 3 seconds, resulting in a cloud of carbon particles. Particles are deposited on the pallet, from which they are transferred into the container. From 5 g of pressed composite obtained 0.40 g of carbon particles with a graphene structure.
3.75 g of nanosized powder bored aluminum (average particle size of 140 nm) and of 11.25 g of powder of PTFE f-42 mixed in a planetary mill. Part of the obtained powder is placed in a mold and heated at a temperature of 160-165°C for 30 minutes, then heated, the powder is pressed at a pressure of 150 kg/cm2. Get a tablet with a diameter of 40 mm and thickness of 5 mm, a Pill wrapped with a nichrome wire, the ends of which lead to the source of electric current, then placed on the stand in a Cabinet with a sealed door, which was rinsed with argon, the wire serves the voltage at this tablet flashes and lights up. As a result of burning pills, the duration of which is not more than 1 second is s, formed a cloud of carbon particles. Particles are deposited on the pallet, from which they are transferred into the container. From 5 g of pressed composite obtained 0.55 g of carbon particles with a graphene structure.
Other examples are given in the table. Indicate in the table below:
h-Al - nanosized aluminum (Sbeats=8-11 m2/g),
ASD-4 powder aluminum spherical particles with a size of 5-8 µm,
n-BA - nano-bore aluminum, received a joint plasma reconcretion aluminum powders and boron (Sbeats=15-35 m2/g),
n-Si - nano-dispersed powder of silicon (Sbeats=50-80 m2/g),
n Al/n-B-60/40 - mechanical mixture of nanosized powders of nano-aluminum and nanopore in %ratio of 60/40,
n-Zr - nano-dispersed powder of zirconium (Sbeats=50-70 m2/g),
n-Ti - nanodispersed titanium powder (Sbeats=40-60 m2/g),
PTFE - powder polyethylenterephtalate,
PTFE/f-42 In 85/15 - mechanical mixture of powders of PTFE and f-42 B in %ratio of 85:15,
n Al/n-B 60/40 - mechanical mixture of powders of nanoaluminum and nanopore in %ratio of 60:40.
|Example||Metal||Fluoropolymer||The ratio of components, %, Me:OP*/td>||The method of mixing||Temperature pressing, °C||Atmosphere|
|1.||n-Al||F-42B||23,4 : 76,6||in acetone||160-165||the air|
|2.||n-Al||F-42B||23,4 : 76,6||in acetone||160-165||argon|
|3.||n-Al||F-42B||23,4 : 76,6||mill||160-165||the air|
|4.||n-Al||F-42B||10,0 : 90,0||mill||160-165||argon|
|5.||ASD-4||F-42B||26,5 : 73,5||in acetone||165-170||the air|
|6.||ASD-4||F-42B||26,5 : 73,5||in acetone||165-170||argon|
|7.||ASD-4||F-42B||26,5 : 73,5||mill||165-170||the air|
|8.||ASD-4||PTFE/f-42B 85/15||35,0 : 65,0||mill||175-180||argon|
|9.||n-BA||F-42B||25,0 : 75,0||in acetone||165-170||the air|
|10.||n-Si||F-42B||20,0 : 80,0||in acetone||165-170||argon|
|11.||n-Si||F-42B||20,0 : 80,0||mill||165-175||the air|
|12.||n-Si||PTFE/f-42B 85/15||25,0 : 75,0||mill||175-180||argon|
|13.||n Al/n-B 60/40||F-42B||25,0 : 75,0||in acetone||165-170||the air|
|14.||n-Zr||F-42B||47 : 53||in acetone||165-170||the air|
|15.||n-Ti||F-42B||33 : 67||in acetone||165-170||the air|
* - Me - metals or their mixture, OP - fluoropolymers
The structure of the obtained particles was studied using scanning electron microscopy (SEM) and x-ray diffractometry. On electron micrographs (Fig.1-3) carbon particles shows that they consist of a thin two-dimensional structures. The thickness of the observed carbon planes considerably the part below the resolution we used electron microscope Philips SEM505, equipped with image capture Capture Micro SEM3.0 M, and elemental microanalysis system with EDAX energy dispersive detector SAPHIRE Si(Li) type SEM10. The resolution of the microscope is about 30Ǻ.
The crystalline structure of the carbon powder was studied by x-ray diffractometer STOE IPDS. The wavelength of the IOCα=0.709 Å. The device allows measurements with a thin x-ray beam the cross-sectional diameter of 500 μm, the step displacement of the beam 10 μm. The analyzed powder was placed between the x-ray transparent micron polymer films in a special holder. The analysis of the experimental results was conducted with the accounting database of the international centre for diffraction data ICDD.
X-ray diffraction on powder carbon product shows that it consists almost entirely of crystalline phase (Fig.4). The diffraction patterns are observed maxima, the exact position of which are shown in tables 2 and 3. Instead of the intense peaks corresponding to reflections (002) and (100)associated with the diffraction of the carbon structures consisting of parallel graphite planes (for example, graphite and multi-walled carbon nanotubes), is observed only break in the field 20-12° and a weak peak at 2Θ=20,61°.
|T the blitz 2|
|Data on x-ray diffraction IOCαradiation for sample carbon residue, obtained after burning pills fluoroplastic f-42B with nano-Al on the air|
|2Θ, deg||D, Å||I, Rel. units||Structure||Crystal system||The Miller indices|
|Data on x-ray diffraction IOCαradiation for sample carbon residue, obtained after burning pills fluoroplastic f-42V with nano-Al in argon|
|2Θ, deg||D, Å||I, Rel. units||Structure||Crystal system||The Miller indices|
Thus, on the basis of the obtained results we can conclude that we installed the conditions of the reaction of nano-or micron aluminum borides of aluminum, silicon, titanium and zirconium with a copolymer of tetrafluoroethylene and vinylidenefluoride formed graphene structure.
Figure 1 Electron micrograph of the carbon particles in the sample 1 of the residue obtained after burning pills fluoroplastic f-42V with nano-Al on the air.
Figure 2 Electron micrograph of the carbon particles in the sample 2 residue obtained after burning pills fluoroplastic f-42V with nano-Al on the air.
Figure 3 Electron micrograph of the carbon particles in the sample 3 of the residue obtained after burning pills fluoroplastic f-42V with nano-Al in argon.
Fig.4 diffraction pattern of sample 2 carbon residue, obtained after burning pills fluoroplastic f-42V with nano-Al.
Method to produce graphene structures in the form of a flat carbon particles of size up to 5 mm, characterized by the fact that graphene structure obtained by firing in an atmosphere of air or inert g is for composite moulding material, derived from micro - and nano-powders of active metals such as aluminum, titanium, zirconium, nanosized powders of silicon and aluminum borides, and fluoropolymers such as polytetrafluoroethylene and a copolymer of tetrafluoroethylene and vinylidenefluoride, when the ratio of metal:fluoropolymer=10-35:90-65%.
SUBSTANCE: invention relates to electrode industry and ferroalloy production and can be applied in production of self-baking electrodes of ferroalloy ore-thermal furnaces. Electrode mass for self-baking electrodes includes anthracite, foundry coke and wastes of siliceous and chrome ferroalloys.
EFFECT: invention makes it possible to increase electric conductivity and increase mechanical strength of electrodes, as well as to reduce consumption of applied coke and coal tar pitch and make use of small waste of ferroalloys.
SUBSTANCE: invention can be used to obtain modified carbon nanotubes. The method of modifying carbon nanotubes includes treatment of carbon nanotubes with an aqueous solution of an oxidising agent in the form of a persulphate or hypochlorite solution at pH higher than 10, carried out simultaneously with mechanical treatment.
EFFECT: invention enables to obtain modified carbon nanotubes having good dispersability in water and in polar organic solvents with low consumption of reactants compared to known methods.
3 cl, 2 ex
FIELD: power industry.
SUBSTANCE: invention may be used when producing carbon nanotubes and hydrogen. Microwave plasma converter comprises flow reactor 1 of radiotransparent heat-resistant material, filled with gas permeable electrically conductive material - catalyst 2 placed into the ultrahigh frequency waveguide 3 connected to the microwave electromagnetic radiation source 5, provided with microwave electromagnetic field concentrator, designed in the form of waveguide-coax junction (WCJ) 8 with hollow outer and inner conductors 9, forming discharge chamber 11 and secondary discharge system. Auxiliary discharge system is designed from N discharge devices 12, where N is greater than 1, arranged in a cross-sectional plane of discharge chamber 11 uniformly in circumferential direction. Longitudinal axes of discharge devices 12 are oriented tangentially with respect to the side surface of discharge chamber 11 in one direction. Nozzle 10 is made at outlet end of inner hollow conductor 9 of WCJ 8 coaxial. Each of discharge devices 12 is provided with individual gas pipeline 13 to supply plasma-supporting gas to discharge zone.
EFFECT: invention permits to increase the reaction volume, production capacity and period of continuous operation, stabilise burning of microwave discharge.
3 cl, 2 dwg
SUBSTANCE: invention relates to a porous carbon composite material. The porous carbon composite material is formed of (A) a porous carbon material, obtained from a material of plant origin, with content of silicon (Si) constituting 5 wt % or higher, as an initial material, and the said porous carbon material has content of silicon constituting 1 wt % or lower, and (B) a functional material, fixed on the porous carbon material, and has specific surface area of 10 m2/g and larger, which is determined by nitrogen adsorption by BET method, and pore volume 0.1 cm3/g or larger, which is determined by BJH method and MP method. The obtained carbon material can be used, for instance, as a medical adsorbent, a composite photocatalytic material, a medication carrier, an agent, a supporting medication release, for selective adsorption of undesired substances in an organism, a filling for blood purification columns, a water-purifying adsorbent, an adsorbing sheet.
EFFECT: invention provides obtaining the material with high functionality.
19 cl, 21 dwg, 8 tbl, 11 ex
SUBSTANCE: invention relates to the field of polymer materials science and can be used in aviation, aerospace, motor transport and electronic industries. Nanotubes are obtained by a method of pyrolytic gas-phase precipitation in a magnetic field from carbon-containing gases with application of metals-catalysts in the form of a nanodisperse ferromagnetic powder, with the nanotubes being attached with their butt ends to ferromagnetic nanoparticles of metals-catalysts. Magnetic separation of the powder particles with grown on them nanotubes, used in obtaining a polymer-based composite material, is carried out. After filling with a polymer, a constant magnetic field is applied until solidification of the polymer takes place. The material contains carbon nanofibres and/or a gas-absorbing sorbent, for instance, silica gel, and/or siliporite, and/or polysorb as a filling agent.
EFFECT: increased mechanical strength, hardness, rigidity, heat- and electric conductivity.
4 cl, 3 ex
SUBSTANCE: invention relates to chemical industry. Carbon-metal material in form of mixture of carbon fibres and capsulated in non-structured carbon nickel particles with diameter from 10 to 150 nanometers are obtained by catalytic pyrolysis of ethanol at atmospheric pressure. Catalyst in form of nickel and magnesium oxides, applied on the surface of graphite foil as inert substrate in dust-like or granulated state, is placed into closed hermetic capacity, in which constant temperature 600 - 750 °C is supported. Ethanol vapour is supplied through input collector, and gaseous pyrolysis products are discharged through output collector. Ethanol vapour is diluted with inert gas, for instance, argon, with weight ratio ethanol: inert gas 1:4…5. Time of synthesis is from 1 to 180 min.
EFFECT: invention makes it possible to obtain carbon nanomaterials from renewable raw material and simplify the process.
6 cl, 3 dwg, 2 ex
SUBSTANCE: invention can be used in obtaining composite materials. Initial carbon nanomaterials, for instance, nanotubes, nanothread or nanofibres, are processed in mixture of nitric and hydrochloric acid at temperature 50-100°C for not less 20 min, washed with water and dried. After that, it is empregnated with alcohol solution of oligoorganohydride siloxane, for instance, oligoethylhydride siloxane or oligomethylhydride siloxane, evaporated, air-dried at temperature not higher than 200°C for not less than 20 min, then tempered in inert medium at temperature 600-800°C for not less than 20 min.
EFFECT: obtained carbon nanomaterials with applied silicon dioxide have high resistance to oxidation.
2 cl, 4 dwg, 6 ex
SUBSTANCE: invention relates to the field of physical and colloidal chemistry and can be used in obtaining polymer compositions. Finely-disperse organic suspension of carbon metal-containing nanostructures is obtained by interaction of nanostructures and polyethylene polyamine. First, powder of carbon metal-containing nanostructures, representing nanoparticles of 3d-metal, such as copper, or cobalt, or nickel, stabilised in carbon nanostructures, are mechanically crushed, after which, mechanically ground together with introduced in portions polyethylene polyamine until content of nanostructures not higher than 1 g/ml is reached.
EFFECT: invention ensures reduction of energy consumption due to the fact that obtained finely-disperse organic suspension of carbon metal-containing nanostructures is capable of recovery as a result of simple mixing.
2 cl, 5 dwg, 2 ex
FIELD: oil and gas industry.
SUBSTANCE: invention pertains to petrochemical industry and plasma chemistry and can be used for plasma processing and disposal of refinery waste. Liquid hydrocarbon material 5 is decomposed by electric discharge in discharger placed in vacuum chamber 6. The device includes copper cathode 1 and anode 2, and busbars 3 connected to them. Cathode 1 is placed in dielectric ditch 4 and its surface is covered with a layer of hydrocarbon material 5 with thickness of 1-4 mm. Voltage sufficient for disruption of interelectrode gap is supplied to cathode 1 and anode 2. Decomposition of hydrocarbon material 5 is made in high-voltage and highly-unbalanced electrical discharge at pressure of 20-50 Torr.
EFFECT: invention provides production speed for the target product obtained of refinery waste.
2 cl, 1 dwg
SUBSTANCE: invention relates to the field of nanotechnology, and particularly to methods for filling the inner cavities of the nanotubes with chemical substances, and can be used to fill the inner cavities of nanotubes with necessary substance when used in the form of nanocontainers and for manufacturing the nanomaterials with new useful properties. In the method of filling the inner cavities of nanotubes with chemical substance the nanotubes are placed in a vacuum chamber, heated in vacuum for desorption of gaseous and liquid impurities, cooled under vacuum, after that the liquid or gaseous chemical substance is placed into the vacuum chamber up to complete coverage of the nanotubes with the liquid chemical substance or before filling the vacuum chamber with gaseous chemical substance up to atmospheric pressure.
EFFECT: increase in the degree of filling of inner cavities of nanotubes with the necessary substance.
FIELD: process engineering.
SUBSTANCE: invention relates to powder metallurgy, particularly, to production of nanocrystalline magnetically soft powders. It can be used for production of high-efficiency electromagnetic protection systems built around radio wave absorbing materials. Initial material, an amorphous band of magnetically soft alloys is subjected to heat treatment at the temperature (0.35-0.37)Tliquidus for 30-90 minutes and, then, cooled in air. Heat treated band is ground in high-rpm disintegrator to nanocrystalline powder with fraction size of 15-35 mcm.
EFFECT: higher efficiency of production at high magnetic permeability.
SUBSTANCE: method of iron powder production involves preparation of iron-carbon melt with the carbon content of 3.9-4.3 wt %, its spraying into water by compressed air, dehydrating, drying to produce raw powder with the proportion of concentration of oxygen to carbon being equal to 1.1-2.0, and grinding down to the particle size of maximum 0.250 mm. The ground raw powder is mixed with granulated iron oxides produced from waste rolling muriatic pickling solutions, with the concentration of impurities of maximum 2 wt % and granule size of maximum 0.160 mm. Concentration of granulated iron oxides in the mix with iron powder is determined, then the obtained mix is annealed in a furnace under the temperature of 950-1000°C for 1.5-2 hours in the layer of 25-35 mm high on a continuously moving band, crushing with the isolation of proper fraction of iron powder with the particle size of less than 0.200 mm.
EFFECT: production of high quality iron powder with high chemical purity, satisfactory fluidity, high compressibility and increased strength of pressing.
2 tbl, 3 ex
SUBSTANCE: invention relates to a matrix carrier composition for use in a pharmaceutical delivery system for oral administration, which is a suspension consisting of particles of a material in a continuous oil phase. The material consisting of particles comprises a first solid phase comprising silicon dioxide nanoparticles having hydrophobic surface, with particle size of 5-1000 nm, and a second solid phase comprising a biopolymer having hydrophilic and hydrophobic parts, said biopolymer containing polysaccharide. Said continuous oil phase is associated with the first and second solid phases, and the weight of the biopolymer is double that of the silicon dioxide nanoparticles. The invention also relates to a method of producing a matrix carrier composition, which includes mixing a first solid phase comprising silicon dioxide nanoparticles with oil, activating a second solid phase containing polysaccharide, wherein activation includes grinding, vacuum treatment, chemical treatment or ultrasonic treatment, adding said activated second solid phase to the oil and mixing the oil containing the first solid phase and oil containing the activated second solid phase.
EFFECT: improved efficiency and bioavailability of a medicinal agent encapsulated in a matrix carrier.
13 cl, 3 dwg, 1 tbl, 8 ex
SUBSTANCE: proposed method comprises making the mix of titanium and lithium compounds to be heat treated, heat treatment products being annealed. Beforehand, said titanium tetrachloride solution is subjected to salt hydrolysis in boiling solution of said tetrachloride at 120÷150°C. Then, formed pulp is filtered to flush obtained precipitate with solution of alkaline agent. The latter is selected from the group consisting of ammonia carbonate, ammonia hydroxide, lithium carbonate, lithium hydroxide. Now, it is flushed with water and dried. Lithium compound with titanium and lithium is selected from the group including: lithium carbonate, hydroxide, oxalate, acetate and mixes thereof. Then, heat treatment is performed at 400-500°C under pyrolysis conditions. Annealing of heat treated mix at conducted at 800-900°C for 5 hours.
EFFECT: simplified production of nanosized particles of spinel-structure powders of lithium titanate Li4Ti5O12.
5 cl, 3 dwg, 2 tbl, 1 ex
SUBSTANCE: invention relates to the chemical industry and can be used to produce composites which are used in photocatalytic processes as catalysts of oligomerisation of olefins and polymerisation of ethylene. The composite material based on silica gel is obtained by precipitation of silicon dioxide from sodium silicate in the presence of titanium dioxide or copper oxide by bubbling of carbon dioxide through the thickness of the suspension at the atmospheric pressure to form the composite material with the type "core (silicon dioxide)/shell (metal oxide)". The method can be used both in the laboratory and in industrial conditions.
EFFECT: invention enables to simplify the process of obtaining a composite, as the need for complex instrumental execution of the process is eliminated, connected with the use of high pressure of carbon dioxide in obtaining the silica gel, as well as environmental safety of the technology, which is connected to the lack of carbon dioxide emissions, achieved by its repeated use.
3 dwg, 2 ex
SUBSTANCE: according to the invention a light emitting device comprises a light emitting element and a wave length converting element which are connected with each other, on the side of the wave length converting element the light emitting element comprises the first zone and the second zone, and on the side of the light emitting element the wave length converting element comprises the third zone and the fourth zone, the first zone has irregular atomic arrangement as compared to the second zone, and the third zone has irregular atomic arrangement as compared to the fourth zone, the first and the third zones are connected directly. Method of manufacturing the light emitting device is also proposed.
EFFECT: invention provides for strong connection between the light emitting element and the wave length converting element.
19 cl, 3 dwg
SUBSTANCE: proposed method comprises mixing of carrier powder with superfine modifying powder in planetary-type mill and compaction of obtained composition. Said superfine modifying powder represents the composition of powders of silicon carbide (SiC) - 50÷70%, silicon nitride (Si3N4) - 20÷30%, sodium hexafluoraluminate (Na3AlF6) - 10÷20% produced by azide process of self-propagating high-temperature synthesis with particle size of 70-100 nm Note here that silicon carbide features β-modification. Said superfine modifying powder carrier represents the copper powder with particle size not over 180 mcm at copper-to-superfine powder ratio of 9:1.
EFFECT: application of modifier of aluminium alloys allows making of dendrites 2,4 time smaller to up the alloy mechanical properties.
1 tbl, 1 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to machine building, particularly, to metal forming. Cutting plate comprises substrate of hard alloy with wearproof ply applied thereon of nanostructured tungsten carbide and niobium carbide with grain size of 20-50 nm at their following ration, wt %: nanostructured tungsten carbide - 90, nanostructured niobium carbide making the rest.
EFFECT: higher wear resistance at hard cutting modes.
1 dwg, 1 tbl
SUBSTANCE: method includes mechanical-activation processing in a planetary ball mill of solid solutions, which contain bismuth and antimony tellurides with an addition of a grinding agent and further sintering of obtained powders. Mechanical-activation processing is carried out successively in two stages: first, with centrifugal acceleration of grinding bodies in the interval from 800 to 1000 m/sec2 for 10-30 min, then with centrifugal acceleration of the grinding bodies in the interval from 20 to 100 m/sec2 for 20-40 min. As the grinding agent used are compounds of a layered structure, selected from the group: MoS2, MoSe, WS2, WSe, BN or graphite. The grinding agent is taken in an amount of 0.1-1.5 wt % of weight of the solid solution of bismuth and antimony tellurides. The obtained thermoelectric material consists of particles of the triple solid solutions of bismuth and antimony tellurides with a size from 5 nm to 100 nm, between which from 1 to 10 nm thick layers of a compound, selected from the group: MoS2, MoSe, WS2, WSe, BN or graphire, are located.
EFFECT: increase of the thermoelectric figure of merit.
2 cl, 3 dwg
FIELD: measurement equipment.
SUBSTANCE: invention relates to gas analysis and may be used to control toxic and explosive gases and in these areas of science and engineering, where analysis of gas media is required. A semiconductor sensitive element according to the invention represents an isolating substrate with previously applied contacts, on which, by application of a film-forming water-alcohol solution SnCl2 with carbon nanotubes they form a layer of nanocomposite of tin dioxide. The sensitive element manufactured in this manner is exposed to drying for 10 minutes at 150°C with subsequent stabilising annealing on air for 30 minutes at temperature of not below 370°C for formation of the nanocrystalline structure.
EFFECT: invention is aimed at increasing value of gas sensitivity and selectivity of a sensor element.
2 cl, 1 dwg
SUBSTANCE: method for synthesis of hollow nanoparticles of γ-Al2O3 is carried out in two steps, the first step including plasma-arc synthesis of an aluminium-carbon material, which includes evacuating a vacuum chamber, filling said chamber with an inert gas, igniting direct-current arc between a graphite electrode and a metal-carbon composite electrode and spraying the composite electrode, which is in the form of a graphite rod with a cavity in which aluminium wire is inserted with weight ratio C:Al of 15:1, and the second step including annealing the synthesized material in an oxygen-containing medium at atmospheric pressure and temperature of 400-950°C for one hour.
EFFECT: obtaining nanodispersed aluminium oxide power, the particles of which are hollow spheres with diameter of 6-14 nm, which is suitable for use in catalytic applications and material science.
2 cl, 5 dwg