621results about "Nitrogen compounds" patented technology

The invention provides silicon nitride and aluminum nitride powder and a preparation method, and relates to the technical field of ceramic powder. The preparation method of the silicon nitride and aluminum nitride powder comprises the following steps: mixing aluminum powder and aluminum nitride raw powder to obtain a first mixture; mixing silicon powder, silicon nitride raw powder and ammonium salt to obtain a second mixture; paving the first mixture and the second mixture in a material frame padded with a carbon felt, and separating the first mixture from the second mixture by using the carbon felt; the material frame is placed in a self-propagating reaction kettle, nitrogen is introduced after vacuumizing, and the first mixture is ignited so as to induce a combustion synthesis reaction of the second mixture; and after the combustion synthesis reaction, cooling to room temperature, releasing the pressure in the self-propagating reaction kettle, taking out a synthetic product, and grinding the synthetic product to obtain silicon nitride powder and aluminum nitride powder. The purity of the powder material can be improved.

An exemplary embodiment of the present disclosure provides a method for making an electrolyte, comprising: providing a solid polymer electrolyte (SPE); incorporating boron nitride with the SPE to form a composite polymer electrolyte (CPE), wherein the boron nitride is at least one of exfoliated hexagonal boron nitride (ex-BN) or fluorine-fimctionalized hexagonal boron nitride (BN-F).

The invention relates to a multi-airflow alternating temperature calcining device for ultra-long nitride single crystal nanofibers. The multi-airflow alternating temperature calcining device comprises a reaction furnace; the mechanical vacuum pressure gauge and the exhaust port are arranged at the top of the reaction furnace; the reaction furnace chamber is arranged in the reaction furnace; the multi-reaction-zone graphite furnace body is arranged in the reaction furnace chamber and comprises a first low-temperature zone, a second high-temperature zone and a third low-temperature zone which are sequentially arranged from bottom to top and are not in contact with one another; the electromagnetic heating controller is arranged on the periphery of the multi-reaction-area graphite furnace body; the graphite boat is movably arranged in the multi-reaction-area graphite furnace body; the movable alumina crucible is arranged in the graphite boat; the graphite columns are arranged at the top and the bottom of the multi-reaction-zone graphite furnace body; the hydraulic cylinder is connected with the graphite column; and a control assembly. Compared with the prior art, the method has the advantages that the nitridation reaction process can be accurately controlled, the fiber quality and the crystal integrity can be improved, and independent and accurate temperature control can be realized.

The invention relates to a preparation method of silicon dioxide-boron nitride nanobelt aerogel, which comprises the following steps: dissolving melamine and boric acid in a co-solvent of tert-butyl alcohol and hot deionized water, stirring and mixing, carrying out ultrasonic treatment, freeze-drying and the like to obtain a melamine-boric acid aerogel precursor, placing the precursor in a tubular furnace, and carrying out vacuum drying to obtain the silicon dioxide-boron nitride nanobelt aerogel. Pyrolyzing in an ammonia gas atmosphere to obtain boron nitride nanobelt aerogel; and placing the boron nitride nanobelt aerogel in a xylene solution containing tetraethoxysilane and silicon tetrachloride, taking out the boron nitride nanobelt aerogel, and drying the boron nitride nanobelt aerogel. And hydrolyzing and pyrolyzing in an inert atmosphere to form a silicon dioxide layer on the surface, thereby obtaining the silicon dioxide-boron nitride nanobelt aerogel. The silicon dioxide and boron nitride nanobelt aerogel is low in density and excellent in mechanical property and oxidation resistance.

The invention provides a pulse-direct current electrochemistry composite deposition process of a nickel-tungsten-phosphorus alloy coating, and belongs to the technical field of coating preparation, and the pulse-direct current electrochemistry composite deposition process comprises the following steps: carrying out silane coupling agent modification treatment on alpha-aluminum oxide; carrying out modification treatment on the hexagonal boron nitride nanosheet by adopting hexadecyl trimethyl ammonium bromide; carrying out polyacrylic acid modification treatment on the nano silicon dioxide; nickel salt, tungsten salt, phosphorus salt, a complexing agent, a buffering agent, a primary brightener, a secondary brightener, a wetting agent, modified aluminum oxide, modified boron nitride, modified silicon dioxide and deionized water are mixed, stirred and heated, and a composite plating solution is obtained; the substrate serves as a cathode, pulse current is applied to the substrate for pulse electroplating, then the current density of the pulse current is continuously and linearly reduced to a target value, and finally direct current electroplating is conducted under the target value; by optimizing the formula of the composite plating solution and the pulse-direct current composite electroplating process, the nickel-tungsten-phosphorus alloy composite plating layer with high hardness, low friction, high wear resistance and corrosion resistance is finally obtained.

This paper discloses a rapid cyclic pressure swing adsorption (PSA) method for separating O2 from N2 and / or Ar. The method uses a carbon molecular sieve (CMS) adsorbent with a driving force of 1 atma and 86 atma, as indicated by a linear driving force model. o F measures at least 5% O2 / N2 and / or O2 / Ar kinetic selectivity and at least 0.2000% O2 adsorption rate (1 / s).

The application discloses a kind of gold nanoparticle loaded oxygen-doped ultrathin porous boron nitride film electrode and preparation method thereof, the preparation method includes the following steps: according to mass ratio 1:3-6:0.25-0.35, boric acid, urea, oxalic acid is prepared oxygen-doped ultrathin porous boron nitride, then gold nanoparticle is loaded oxygen-doped ultrathin porous boron nitride and coated on conductive substrate to form film electrode.The oxygen-doped ultrathin porous boron nitride film electrode loaded with gold nanoparticles prepared by the application has the advantages of large specific surface area, high electron-hole separation efficiency, fast electron transfer rate, etc., is a new type of film electrode with excellent photoelectric performance, meets the actual production demand, and has wide application prospect in photoelectrochemical field.The preparation method also has the advantages of simple process, easy operation, high preparation efficiency and low cost, and is suitable for large-scale preparation, which is beneficial to industrial application.

The invention relates to Al2O3 / C powder as well as a preparation method and application thereof, and belongs to the field of ceramic powder preparation. The invention relates to a preparation method of Al2O3 / C powder, which comprises the following steps: by taking aluminum acetate as a raw material, acrylamide as an organic monomer, N, N '-methylenebisacrylamide as a cross-linking agent and ammonium persulfate as an initiator, forming polymer gel with a three-dimensional network structure through a sol-gel method, and drying to obtain dry gel powder; and pyrolyzing the dry gel powder in nitrogen to obtain Al2O3 / C powder with a porous structure characteristic. According to the invention, acrylamide is utilized to form gel with a three-dimensional network structure, Al < 3 + > is trapped in pores of the gel structure, so that an aluminum source and a carbon source are uniformly distributed on a molecular level, and growth of Al2O3 particles is effectively inhibited by utilizing an isolation effect of C and combining a rapid heating process, so that the diffusion distance of a substance for forming AlN is greatly shortened, and the preparation process is simplified. According to the method, rapid formation of AlN is promoted, the reaction time is effectively shortened, the efficiency is improved, and the obtained pure-phase AlN powder is small in particle size.

The invention provides crystalline silicon nitride powder that can yield a silicon nitride sintered body with easy sinterability and excellent sintered body properties including high-temperature strength. It further provides crystalline silicon nitride powder that allows production of a silicon nitride sintered body having sufficient mechanical strength as well as excellent thermal conductivity. It still further provides a method for producing a silicon nitride sintered body having high flexural strength and excellent thermal conductivity. The crystalline silicon nitride powder has a specific surface area (SA) of 3 m2 / g to 16 m2 / g as measured by the BET method, a surface oxygen amount (FSO) of 0.2 mass% to 0.6 mass% as measured by temperature increase mode analysis, an internal oxygen amount (FIO) of 0.4 mass% to 1.3 mass% as measured by temperature increase mode analysis, and a ratio (FSO / SA) of surface oxygen amount to BET specific surface area of 0.25 mg / m2 or higher and lower than 0.50 mg / m2.

A structure includes boron nitride nanotubes, wherein the structure (i) is an extension region in a field-effect transistor or (ii) comprises a metallic interconnect to reduce the dielectric constant and therefore the RC-delay in the device. Also, a field-effect transistor structure includes a low-k spacer layer between metallic interconnects, wherein the low-k spacer layer includes boron nitride nanotubes. In addition, a method for reducing RC delay in an integrated circuit includes forming a component of the integrated circuit from boron nitride nanotubes.

The application discloses a transfer method of a two-dimensional material film, which comprises the following steps: coating photoresist on the surface of a two-dimensional material film directly grown on a growth substrate and solidifying the photoresist to form a transfer medium layer; separating the growth substrate from the transfer medium layer / two-dimensional material film; after the transfer medium layer / two-dimensional material film is attached to a target substrate, heating is performed to melt the transfer medium layer; and the transfer medium layer is removed. The transfer method of the application utilizes the characteristic that the photoresist can be softened at a low melting point after being solidified, and firstly solidifies the photoresist on the surface of the two-dimensional material film to be transferred to serve as a support medium for the transfer of the film, so that the transfer of the film is realized. After being transferred to the target substrate, the solidified photoresist can be softened, so that the transferred two-dimensional material film can be fully contacted with the target substrate, and the complete and intact transfer of the two-dimensional material film can be realized. The transfer method of the application is especially suitable for the transfer to a rough target substrate.

The disclosed subject matter relates to methods for the dispersion processing of high aspect ratio nanomaterials, such as boron nitride nanotubes, into macrostructures. For example, the disclosed subject matter relates to boron nitride nanotube fibers and films, and methods of making and use thereof. In some examples, the methods are surfactant-free and / or sonication-free.

The application relates to a preparation method of a hot-pressing cubic boron nitride precursor, which uses hexagonal boron nitride with appropriate particle size as raw material, and obtains the precursor through pretreatment such as drying, hot pressing, catalyst mixing and grinding. The precursor obtained by the method has high forming density, can inhibit pressure loss caused by volume collapse in the synthesis process of cubic boron nitride, is suitable for large-scale production, improves the conversion rate of h-BN to c-BN, and reduces the production cost.

To provide a composition which contains a tetrafluoroethylene-based polymer and predetermined inorganic particles, is excellent in dispersibility and moldability, and can form a molded product low in linear expansion coefficient, dielectric constant and dielectric loss tangent and excellent in adhesion to a substrate, thermal conductivity and heat dissipation.SOLUTION: The composition contains a tetrafluoroethylene-based polymer and hydrophobic inorganic particles surface-treated with a coupling agent. The coupling agent is a compound in which a trialkoxysilyl group and a functional group are bonded via a linking group containing one or more selected from an imino bond, an amide bond, a urea bond, a urethane bond and a carbodiimide bond.SELECTED DRAWING: None

The purpose of one aspect of the present invention is to provide a hexagonal boron nitride powder having high crystallinity and improved thermal conductivity of a resin. In order to solve the above-mentioned problem, one aspect of the present invention relates to a hexagonal boron nitride powder in which the ratio of the spectral intensity at a wavelength of 227 nm to the spectral intensity at a wavelength of 330 nm as measured by the cathodoluminescence (CL) method is 1.0 or more.

The application relates to an in-situ composite preparation method of a calcium phosphate / boron nitride high-temperature wave-absorbing material and application thereof, and belongs to the technical field of wave-absorbing materials. The method solves the problem that traditional insulator materials boron nitride have no electromagnetic wave absorption capacity. The method comprises the following steps: preparing Ca3(PO4)2 ion oligomers; preparing Ca3(PO4)2 ion oligomer gel; preparing a transparent hot solution of melamine diboric acid, then mixing the transparent hot solution of melamine diboric acid with the Ca3(PO4)2 ion oligomer gel, and then cooling, centrifuging, drying and sintering, so that the preparation is completed. The calcium phosphate / boron nitride high-temperature wave-absorbing material is prepared by adopting the in-situ composite mode, the process is simple, the cost is low, the process is green and pollution-free; the wave-transparent boron nitride material is converted into a wave-absorbing material through the simple composite of inorganic non-metallic substances, the balanced magnetic property and polarization effect of the material are matched with each other, high-strength and wide-band electromagnetic wave absorption performance is finally realized, and meanwhile, the lightweight and high-temperature-resistant characteristics of boron nitride are maintained.

The application relates to a three-dimensional hollow network structure boron nitride, and a main process of a preparation method thereof is as follows: taking citric acid, sodium borate and strontium carbonate as raw materials, a boron-containing precursor is obtained through a sol-gel method; then, the boron-containing precursor is pre-nitridated under a nitrogen-containing atmosphere to obtain a pre-nitridation product; next, the pre-nitridation product is uniformly mixed with ammonium borate and ammonium chloride through ball milling, and then is placed into a high-pressure reaction kettle to react, so that the three-dimensional hollow network structure boron nitride is obtained. The three-dimensional hollow network structure boron nitride prepared by the application has a connected network structure formed by multiple cavity units, has high purity, provides a new idea for preparation of a hollow boron nitride structure, and has a good application prospect in the fields of gas adsorption, water pollution treatment, hydrogen storage and a drug carrier.

Provided is a powder having excellent concealing power, such that the powder can be used in place of titanium dioxide as a white pigment in a cosmetic. This powder comprises planar crystal particles, the volume D50% diameter thereof is 0.7-8.0 µm, and the coefficient of variation (CV value) of the primary particle diameter is 1.0 or less.

The present application relates to graphene material and its preparation technology, specifically to a method for growing graphene on the surface of non-metallic particles on a large scale, which is suitable for large-scale preparation of graphene-coated non-metallic powder material. The present application uses a two-step method to grow graphene uniformly on the surface of a large number of non-metallic particles: first, mix a large number of non-metallic particles with a carbon source, and form a bulk composite material of non-metallic particles and carbon through low-temperature carbonization; then, pass current to the above bulk composite material using electrodes to heat it to a higher temperature, convert the carbon into graphene, until graphene-coated non-metallic particles are obtained, which are separated from each other, and the high-temperature heating process stops spontaneously. The present application can grow a graphene layer on the surface of a large number of non-metallic particles, the method is easy to scale up, and has the characteristics of good uniformity of graphene coating and high particle separation degree; at the same time, by taking advantage of the large resistance of graphene-coated non-metallic particles which are separated from each other, the high-temperature heating process stops spontaneously.

The present disclosure aims to provide hexagonal boron nitride powder, etc., for obtaining a resin composition that achieves both excellent thermal conductivity and dielectric strength. A hexagonal boron nitride powder according to one aspect of the present disclosure is a hexagonal boron nitride powder containing hexagonal boron nitride aggregates (101), characterized in that the average particle size is 25 μm or more and 70 μm or less, the cumulative frequency of particle size of 40 μm or more in the volume-based particle size distribution is 65% or more, the tap bulk density is 0.84 g / mL or more and 1.05 g / mL or less, and the oil absorption is 50 mL / 100 g or more and 84 mL / 100 g or less.

The application provides a high-rate long-cycle natural graphite-based composite negative electrode material and a preparation method and application thereof. The natural graphite-based composite negative electrode material has the characteristics of high-rate performance, low volume expansion performance and long-cycle performance. Firstly, submicron flake graphite particles are granulated into particles with a pore structure in a form of spray granulation; then, heat treatment is performed under a protective atmosphere to convert pitch into amorphous carbon; then, chemical vapor deposition technology is adopted to uniformly distribute nano titanium in the pore structure between the submicron flake graphite inside the spherical graphite particles and on the surface of the spherical graphite particles; subsequently, the nano titanium is converted into titanium nitride through nitriding treatment, that is, titanium nitride is deposited in the pore structure between the submicron flake graphite inside the spherical graphite particles and on the surface of the spherical graphite particles, to prepare the natural graphite-based composite negative electrode material.

A continuous-flow plasma-electrochemical system for redox reactions includes a flow-type plasma reactor configured to receive feedstock and to generate an output comprising intermediate species. An electrochemical reactor is configured to receive the intermediate species from the plasma reactor and to generate an output having the desired product (e.g., ammonia).

The application provides an in-situ oriented carbon nanotube / silicon nitride nanobelt composite material and a preparation method thereof, and comprises the following steps: uniformly mixing methyltrimethoxysilane, dimethyldimethoxysilane, ethanol, water and nitric acid according to a certain proportion, and obtaining a siloxane xerogel precursor after stirring and drying; obtaining a silicon nitride nanomaterial by a carbothermal reduction reaction method under high-temperature conditions; injecting a mixed solution of ethanol, ethylenediamine and ferrocene into a tube furnace by a floating CVD method under high-temperature conditions, and growing carbon nanotubes on the surface of the silicon nitride nanobelt to obtain the in-situ oriented carbon nanotube / silicon nitride nanobelt composite material; and the application grows the carbon nanotubes on the surface of the silicon nitride nanobelt material by the floating CVD method to improve the electromagnetic shielding performance of the silicon nitride nanocomposite material, and finally, the carbon nanotube / silicon nitride nanobelt composite material with light weight, flexibility and good electromagnetic shielding performance is prepared.

An aluminum nitride powder in which, in a particle size distribution measured by a laser diffraction / scattering particle size distribution instrument, the cumulative volume 50% particle size (D50) is 0.3-1.0 [mu] m, the proportion of particles having a cumulative volume 50% particle size (D50) of 0.20 [mu] m or less is 10% or less in terms of volume frequency, the ratio of the average primary particle size (Dp: [mu] m) of 500 particles observed at a magnification of 20,000 times by a scanning electron microscope to the D50, D50 / Dp, is 1.0-1.4, and the average particle size (Dp: [mu] m) of the particle size distribution measured by a laser diffraction / scattering particle size distribution instrument is 1.0-1.4. And the average circularity is 0.7 or more.

To provide a method for producing hexagonal boron nitride powder in which a hexagonal boron nitride powder is effectively reacted with a surface treatment agent.SOLUTION: Provided is a method for producing modified hexagonal boron nitride powder, and includes a heating step of heating hexagonal boron nitride powder at a temperature of 1300°C or higher and 2200°C or lower in a nitrogen atmosphere, and a second surface treatment step of contacting the re-calcination hexagonal boron nitride powder after the heating step with a surface treatment agent having a conjugated double bond.SELECTED DRAWING: Figure 1

A system and method are provided for obtaining nitrogen and carbon dioxide gas from flue gas. A method according to some embodiments involves receiving flue gas at the inlet of a selective catalytic reduction system, wherein the flue gas is one or more NO x The system includes a gas and one or more NOs in a selective catalytic reduction system. x The method includes reducing a gas to N2 gas, receiving output gas from a selective catalytic reduction system at the inlet of a gas separation membrane, and separating the output gas into a retained substance and a permeate using the gas separation membrane, wherein the retained substance comprises N2 gas.

The invention belongs to the technical field of synthesis and preparation of aluminum nitride, and discloses a controllable and extensible preparation method of a one-dimensional aluminum nitride nanowire / nanotube, which comprises the following steps: (1) uniformly mixing a solid aluminum source and a solid nitrogen source, transferring the mixture into a rotatable crucible, transferring the crucible into a tubular furnace, sealing the tubular furnace, and carrying out heat preservation for 2-3 hours; vacuumizing and then introducing protective gas; (2) under the condition that protective gas is continuously introduced, the tubular furnace is heated to a preset target temperature for a nitridation reaction, and the nitridation reaction is carried out under the condition that a crucible rotates at a constant rotating speed; and after the reaction is finished, cooling the tubular furnace and stopping the rotation of the crucible to obtain a one-dimensional aluminum nitride nanowire or nanotube product. According to the method, the solid aluminum source and the solid nitrogen source are used as raw materials, and the crucible rotation is introduced during the nitridation reaction to carry out dynamic enabling improvement, so that the single-crystal aluminum nitride nanowire or nanotube with high purity and uniform morphology can be efficiently synthesized.

A nitride semiconductor material having low lattice thermal conductivity and a heat flow switching element including the same are provided. The nitride semiconductor material according to the present invention is a metal nitride represented by M-Si-N-Te (where M represents at least one kind of transition metal element, and Te represents an arbitrary element), and has a thermal effusivity of less than 2000 Ws0.5 / m2K. In particular, the M is at least one of Cr, Mn, Ni, Mo, and W. In addition, a heat flow switching element according to the present invention includes an N-type semiconductor layer 3, an insulator layer 4 formed on the N-type semiconductor layer, and a P-type semiconductor layer 5 formed on the insulator layer, wherein at least one of the N-type semiconductor layer and the P-type semiconductor layer is formed from the nitride semiconductor material described above.

A kind of low agglomeration aluminum nitride powder preparation method, comprising the following steps: S1: 50-60 parts of aluminum nitrate nine water, 60-80 parts of film-forming solution and 20-30 parts of glucose monohydrate are mixed uniformly, after stirring 1-2h, it is poured into polytetrafluoroethylene dish at room temperature 25 ℃ and is stationary 4-6h, and crosslinked film is obtained;S2: the crosslinked film obtained in step S1 is burned at 300-400 ℃ for 30-40 min in argon environment, calcined at 800-900 ℃ for 1-2h in ammonia environment, then at 900-1000 ℃, heat preservation 1-2h, finally at 1200-1400 ℃, calcined 1-2h, and aluminum nitride powder is obtained.The low agglomeration spherical aluminum nitride powder machine preparation method of the application, the particle size of the prepared aluminum nitride powder is fine, the agglomeration rate is low, the conversion rate is high and the specific surface area is large.

The present invention relates to a process for the production of hydrogen bis(chlorosulfonyl)imide (HCSI), said process comprising the following steps: (i) providing to a reactor a composition (H) comprising an amount (CSI-1) of chlorosulfonyl isocyanate, an amount (CSA-1) of chlorosulfonic acid, and at most 20% by weight, based on the total weight of the composition (H), of an amount (HCSI-1) of HCSI; and (ii) heating said composition (H). The present invention also relates to a method for recycling a composition (H) as defined above, said method comprising feeding said composition (H) to a reactor and heating said composition (H) at a temperature below 150°C.