179 results about "Boron oxide" patented technology

The invention provides a thermal response self-ceramization fireproof coating and a preparation method thereof. The thermal response self-ceramization fireproof coating is prepared from the following raw materials in parts by mass: 3 to 10 parts of acrylic monomer, 3 to 10 parts of organic sulfonate, 1 to 4 parts of silane coupling agent, 0.5 to 3 parts of silicate ester, 4 to 6 parts of ceramic precursor, 3 to 6 parts of fluxing agent and 0.05 to 0.4 part of initiator. The fluxing agent comprises a component A and a component B, the component A is one of boric oxide, zinc borate or low-melting-point glass powder, and the component B is one of phosphorus pentoxide and ammonium polyphosphate. The silane coupling agent can be copolymerized with an acrylic monomer to construct a C-C main chain, the C-C main chain and silicate ester are subjected to hydrolytic condensation to form a Si-O-Si three-dimensional network, a chemical cross-linked skeleton is formed, and the chemical cross-linked skeleton can generate silicon dioxide at high temperature to participate in a ceramization reaction; the ceramic precursor and silicate ester can form a strong physical cross-linking effect, so that the fireproof coating with a chemical and physical double-cross-linked network can be formed, and the fireproof coating has excellent mechanical property and machinability at normal temperature.

The invention discloses high-strength high-temperature-resistant fireproof industrial glass and a preparation method thereof, and relates to the technical field of glass manufacturing. The industrial glass is prepared from the following raw materials: silicon dioxide, boric oxide, aluminum oxide, sodium oxide, potassium oxide, niobium phosphate, a composite reinforcing component and a clarifying agent, the composite reinforcing component is prepared from hafnium oxide, gadolinium oxide and zinc oxide; the clarifying agent is obtained by mixing cerium dioxide and tin oxide. The preparation method of the industrial glass comprises the following steps: preparing functional components, melting glass, forming a glass substrate, and preparing the industrial glass. The prepared industrial glass is high in strength, good in high-temperature stability and excellent in fireproof performance.

A method and an apparatus for conformal boron doping of a three-dimensional structure. The method comprises: removing an oxide layer from a surface of a silicon-based three-dimensional (3D) substrate; forming, after removing the oxide layer, a first group of stacked films on a surface of the silicon-based three-dimensional substrate; forming a second group of stacked films on a surface of the first group of stacked films away from the silicon-based 3D substrate; depositing an aluminum oxide passivation layer on a surface of the second group of stacked films away from the first group of stacked films; and boron-doping the silicon-based 3D substrate through laser annealing or rapid thermal annealing, where the laser annealing or the rapid thermal annealing drives boron dopants, which comprises boron oxide, into the silicon-based 3D substrate via an auxiliary layer.

The invention relates to the technical field of refractory materials, in particular to an antioxidant and application thereof in steel ladle slag line bricks, and the antioxidant comprises a Si / SiC multiphase material, modified nano Al2O3 and CaF2; the ladle slag line brick comprises an antioxidant, fused magnesite, crystalline flake graphite and phenolic resin. Si-SiC compound waste is subjected to magnetic separation and acid pickling, then a SiO2 passivation layer is formed through pre-oxidation, moisture and air in the storage period are isolated, and a titanate coupling agent is introduced to improve the wettability and compatibility with phenolic resin. P2O5 released by phosphate on the surface of the modified nano Al2O3 at a high temperature reacts with alkali (earth) metal migrated to a SiO2 oxide layer to prevent the alkali (earth) metal from forming a low-melting-point eutectic substance, CaF2 reacts with SiO2 along with temperature rise, a passivation layer is broken, internal Si and SiC are directly exposed, and boron oxide of the modified nano Al2O3 remarkably reduces activation energy and a temperature threshold value of the reaction of CaF2 and SiO2.

The invention belongs to the technical field of electrode material preparation, and particularly relates to a preparation method of boric acid-assisted low-temperature sintered porous aluminum foil. The preparation method comprises the following steps: dispersing aluminum powder, boric acid and binder raw materials in a solvent to form dispersed slurry; and coating a matrix with the dispersed slurry, drying, sintering at 450-600 DEG C under protective gas, reacting boric acid with aluminum oxide on the surface of the aluminum powder to form low-melting-point aluminoborate, reducing the sintering temperature, promoting aluminum atom diffusion, increasing sintering neck formation, and sintering to obtain the porous aluminum foil. Boron oxide generated by decomposition of boric acid is added to react with aluminum oxide to form low-melting-point aluminoborate, the sintering liquidus temperature is reduced, aluminum atom diffusion is promoted, and low-temperature sintering at 450-600 DEG C is achieved. The aluminum powder sintered foil is suitable for energy storage devices such as an aluminum electrolytic capacitor and a lithium ion battery, has the advantages of low-temperature energy conservation, high porosity and strong mechanical property, and solves the problems of aluminum oxide obstruction and high high-temperature energy consumption of the traditional aluminum powder sintered foil.

The application discloses a hydrodesulfurization catalyst and a preparation method and application thereof. The hydrodesulfurization catalyst comprises a carrier and a second active metal component; the carrier comprises a first active metal nitride, a first active metal carbide, boron oxide and aluminum oxide; wherein the molar ratio of the first active metal nitride to the first active metal carbide, in terms of the first active metal, is 1:0.15-0.25. The hydrodesulfurization catalyst has the characteristics of good macromolecular diffusion performance, strong desulfurization capacity and good carbon deposition resistance. The hydrodesulfurization catalyst is particularly suitable for a residual oil hydrodesulfurization treatment process and has good desulfurization activity and stability.

The invention relates to the technical field of modified carbon graphite materials, and particularly discloses an antioxidant modified carbon graphite material and a preparation method thereof, the antioxidant modified carbon graphite material comprises the following raw materials by weight: 30-34 parts of medium temperature pitch, 4-6 parts of modified silica sol and 10-12 parts of artificial graphite powder; from two aspects, firstly, the aluminum dihydrogen phosphate and the boric acid aqueous solution are added, the aluminum dihydrogen phosphate can promote the asphalt to form a denser and firmer glassy carbon structure during carbonization, and phosphorus pentoxide generated by decomposition of the aluminum dihydrogen phosphate and boron oxide generated by dehydration of boric acid can generate a glass phase with an anti-oxidation effect; secondly, core-shell particles are added, a shell layer of the core-shell structure is an aluminum hydroxide structure generated by hydrolyzing aluminum nitrate nonahydrate, and an inner core is epoxidized nano silicon carbide; through the synergistic effect of the two, the mechanical property and the oxidation resistance of the carbon-graphite material are improved.

The invention provides high-purity superfine titanium diboride and a preparation method thereof, and relates to the field of titanium diboride preparation. The method comprises the following steps: mixing boron oxide, titanium hydride, a carbon source, nano rare earth oxide and an organic solvent, and drying to obtain a mixture; in a vacuum environment, performing first roasting on the mixture to obtain a first roasted material; and in an oxygen-containing atmosphere, carrying out second roasting on the first roasting material to obtain the high-purity superfine titanium diboride. In the first roasting process, boron oxide, titanium hydride and a carbon source are completely melted and fully contacted, then further, the carbon source forms a carbon skeleton, the contact area between the melted boron oxide and titanium hydride and the carbon skeleton is further enlarged, liquid-liquid mixing and the increase of the contact area can reduce the reaction kinetic conditions, the reaction temperature is greatly reduced, and the reaction time is greatly shortened. The particle size of the generated titanium diboride is reduced, and the molten boron oxide and titanium hydride react on the porous carbon skeleton in a liquid-liquid form to generate the high-purity superfine titanium diboride.

The invention provides a TOPCon battery and a preparation method thereof, and boron diffusion equipment, and the preparation method of the TOPCon battery comprises the steps: providing a silicon substrate, placing the silicon substrate in a boron diffusion furnace, introducing nitrogen into a furnace mouth region of the boron diffusion furnace, introducing oxygen and boron trichloride into the boron diffusion furnace, introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, and introducing nitrogen gas into the furnace mouth region of the boron diffusion furnace, the ratio of the flow of the oxygen to the flow of the boron trichloride is alpha, and alpha is more than or equal to 3.5 and less than or equal to 4.5. The nitrogen can quickly purge reaction byproducts in a low-temperature area of the furnace mouth, and sufficient oxygen is provided to completely oxidize boron trichloride into a gaseous boron oxide precursor before the boron trichloride enters a high-temperature reaction area, so that the generation of viscous low-temperature boron oxide due to insufficient oxidation is avoided; and the generation and deposition of boron oxide crystals at the furnace mouth are inhibited from two dimensions of mass transfer process and chemical reaction completeness, and the yield and average photoelectric conversion efficiency of the TOPCon battery can be remarkably improved.

This invention discloses a method for preparing high rare-earth-doped low-loss boron-containing glass optical fibers. The steps are as follows: weigh glass raw materials containing rare-earth oxides and boron oxide, mix them uniformly, and place them in a high-temperature furnace. First, heat the mixture under a high-purity nitrogen atmosphere, then switch to a high-purity oxygen atmosphere or a high-purity air atmosphere for continued heating. The resulting glass melt is cooled and annealed to obtain a large glass block. The glass is then processed into a preform and placed in an optical fiber drawing furnace for fiber drawing under a high-purity oxygen atmosphere, thus achieving the preparation of high rare-earth-doped low-loss glass optical fibers. This invention eliminates the additional glass matrix absorption in the near-infrared region caused by boron in boron-containing glass optical fibers and also transforms the transition metal impurity ions from a low valence state with broad absorption in the near-infrared region to a high valence state with narrow low absorption in the near-infrared region. Both of these aspects significantly reduce the matrix absorption of boron-containing glass optical fibers, providing possibilities for the application of high rare-earth-doped low-loss glass optical fibers.

The invention relates to the technical field of ceramic substrates, and provides a multilayer ceramic substrate metallization method, which comprises the following steps: S1, cleaning and drying a ceramic substrate to obtain a treated ceramic substrate; s2, printing the printing slurry on the treated ceramic substrate, and carrying out drying, lamination, pressing and sintering to obtain a metalized multilayer ceramic substrate; the printing paste comprises the following components in parts by weight: 80 parts of conductive powder, 4-8 parts of zinc oxide, 8-12 parts of boric oxide, 3-5 parts of bismuth oxide, 5-10 parts of titanium-doped aluminum oxide, 4-8 parts of guar gum, 1-2 parts of hydrogenated castor oil and 15-20 parts of a solvent; the titanium-doped aluminum oxide comprises the following raw materials: aluminum oxide and water-soluble titanium salt in a weight ratio of 18: (2-7). According to the technical scheme, the problem that the heat-conducting property of the ceramic substrate is poor when the glass powder is added in the prior art is solved.

The present application belongs to the technical field of steel metallurgy continuous casting, and particularly relates to a crystallizer non-lithium protecting slag for stainless steel slab continuous casting and application. The non-lithium protecting slag is composed of the following components: calcium oxide 28-40%, silicon oxide 26-38%, aluminum oxide 2-8%, sodium oxide 9-14%, fluoride ion 5-11%, magnesium oxide 1-4%, boron oxide 1-5%, manganese oxide 0.5-3%, total carbon 2-4.5%, and the rest is inevitable impurities and carbonate volatiles; the mass ratio of sodium oxide / magnesium oxide is greater than or equal to 3.5. The hollow particle type protecting slag product designed in the present application can reduce the ton slag cost by 1000-2500 yuan, and has the performance of the conventional lithium-containing austenitic stainless steel slab continuous casting protecting slag, and is beneficial to the smooth running of the austenitic stainless steel high-pulling speed continuous casting process, and reduces the raw material procurement cost of the steel enterprise, so that the market competitiveness of the stainless steel product can be further enhanced.

The invention discloses a preparation method of silver-coated copper slurry suitable for TOPCON, and relates to the technical field of battery preparation, and the preparation method comprises the following steps: preparing silver-coated copper particles; silver-coated copper particles are mixed with a glass system, an organic system and nanoscale silver particles according to the mass ratio to prepare silver-coated copper slurry; the silver-coated copper particles sequentially comprise a copper core, an aluminum oxide protection layer, a nickel layer and a nano-silver coating layer from inside to outside, and the silver-coated copper slurry is formed by mixing the silver-coated copper particles, a glass system, an organic system and nano-scale silver particles according to a mass ratio. The glass system is composed of bismuth oxide-boric oxide composite glass, zinc oxide-silicon oxide composite glass and tellurium oxide glass. According to the invention, the silver-coated copper particles with a multi-layer coating structure are used as a main conductive phase and are combined with the nano-silver particles, so that the conductive performance is ensured, the raw material cost of the paste is reduced, the cost pressure is dealt with, the problems of copper core oxidation and ion migration are solved, and the paste can be kept stable in a high-temperature and high-humidity environment.

This invention relates to the field of glass-ceramic technology, specifically providing a low-temperature co-fired ceramic, its preparation method, and its application. The raw materials for the low-temperature co-fired ceramic include VSBBS glass frit and ceramic frit, with the total weight of the VSBBS glass frit and ceramic frit being 100%. The mass percentages of the VSBBS glass frit and ceramic frit are 20-40% and 60-80%, respectively. The raw materials for the VSBBS glass frit, by mass percentage, include 10-30 wt% vanadium oxide, 10-30 wt% antimony oxide, 10-30 wt% barium oxide, 10-20 wt% boron oxide, and 30-50 wt% silicon oxide, with the sum of all oxides being 100%. The LTCC material obtained by this invention achieves excellent millimeter-wave dielectric properties, with a relative permittivity between 4.8 and 6.8, a dielectric loss less than or equal to 0.001, and a flexural strength of 180-230 MPa.

Provided are glasses containing silicon dioxide (Si02) and / or boron oxide (B203) as glass formers and having a refractive index n greater than or equal to 1.9 d (at 587.56 nm) and a density (measured at 25 °C) less than or equal to 5.5 g / cm 3 Optionally, the glasses can be characterized by high transmission in the visible and near-ultraviolet (near-UV) range of the electromagnetic spectrum and / or good glass forming ability.

The present invention developed a composite having a novel structure containing, in a high content, a powder having a radiation-shielding function.　Provided is a composite having a radiation-shielding function and a method for producing the same. The composite comprises a preform made from a mixture containing a liquid silica-based binder and one or more radiation-shielding powders selected from gadolinium oxide, boron carbide, boron oxide, boron, barium sulfate, strontium oxide, tungsten, tungsten oxide, tungsten carbide, molybdenum, molybdenum oxide, iron powder, iron oxide powder, and ferrite powder, the radiation-shielding powder(s) being contained in the range from 3% to 85% in total. All of the voids in the preform are impregnated and filled with molten aluminum and solidification is allowed to occur to form a composite, or 25% or more of the voids in the preform are impregnated with a liquid organic / inorganic sealing agent and solidification is allowed to occur to form a composite. The liquid silica-based binder has properties that allow the preform to be formed at a temperature at which the radiation-shielding powder(s) does not decompose.

The present application relates to the technical field of batteries, and specifically relates to a silicon-carbon negative electrode material, and a preparation method therefor and the use thereof. The silicon-carbon negative electrode material of the present application comprises a base body and a coating layer coating the surface of the base body, wherein the base body comprises an inner core and a composite layer located on the surface of the inner core, with the inner core comprising graphite, and the composite layer comprising nano silicon and boron oxide; and the coating layer comprises nano carbon. In the silicon-carbon negative electrode material of the present application, graphite serves as the inner core, and by means of boron oxide, nano silicon is uniformly adhered to the surface of graphite, such that the adhesion of nano silicon to graphite can be improved, thereby preventing the silicon material from falling off the surface of graphite during a charging and discharging process. The nano carbon coating layer can avoid side reactions caused by direct contact of silicon particles with an electrolyte, and can also increase the electronic conductivity of the silicon-carbon negative electrode material. The silicon-carbon negative electrode material of the present application has excellent comprehensive electrochemical performance.

The application discloses a composite photocatalyst of B-doped g-C3N4 microrod loaded with WO3 short fibers and a preparation method thereof. The method comprises the following steps: melamine, boron oxide, sodium tungstate dihydrate, urea and cetyltrimethylammonium bromide are proportioned according to the mass ratio of (1-10):(0.5-4):(1-6):(1-5):(0.2-3) to obtain a mixed powder, 60 mL of methanol is added, the mixture is fully dispersed, and then the mixed solution is quickly poured into a lining in a reaction kettle; the reaction kettle is sealed, placed in a vacuum drying box, and kept at 60-150 DEG C for 2-10 h, the reaction solution is poured out after cooling, centrifuged, washed and dried to obtain a precursor WB-CN; the WB-CN prepared in step two and ammonium fluoride are taken according to the mass ratio of (1-10):(0.5-3), ground, and then put into a white porcelain boat, covered, and placed in a muffle furnace for calcination, the heating speed is 4-10 DEG C / min, the temperature is 500-650 DEG C, and the holding time is 2-5 h; after calcination, the sample is dispersed in water, fully stirred, then centrifuged, washed and dried, so as to obtain a WO3 / B-g-C3N4 photocatalyst with stable structure and high hydrogen production efficiency, and the microstructure of the WO3 / B-g-C3N4 photocatalyst is that the WO3 short fibers are uniformly loaded on the g-C3N4 microrod.

The application discloses a surface-coated and bulk-gradient co-doped sodium ion battery positive electrode material and a preparation method and a sodium ion battery thereof, and belongs to the technical field of sodium ion batteries. The sodium ion battery positive electrode material comprises a layered transition metal oxide and a coating layer coated on the surface of the layered transition metal oxide; the layered transition metal oxide is a nickel-iron-manganese-based layered transition metal oxide, and the coating layer is an amorphous boron oxide coating layer; the chemical formula of the surface-coated and bulk-gradient co-doped sodium ion battery positive electrode material is Na(Ni 1 / 3 Fe 1 / 3 Mn 1 / 3 ) x B y M z O2, 0.9≤x≤0.98, 0.01≤y<0.2, 0.01≤z<0.1, and x+y+z=1, and M is selected from W or Nb; wherein the doping concentration of boron elements and metal M elements presents a gradient decreasing trend from the surface layer to the inside along the radial direction; the surface boron oxide coating and the bulk-gradient doping of boron elements and metal M elements are simultaneously realized; the surface coating layer effectively reduces the interface side reaction, and the bulk-gradient doping stabilizes the crystal structure from the inside; and the two synergistically act to jointly inhibit the structural degradation in the cycle process.

The invention belongs to the technical field of liquid-phase benzylamine compound catalytic oxidation application catalysts, and particularly relates to application of a two-dimensional boron oxide alkene nanosheet catalyst to preparation of imine by catalyzing oxidative coupling of benzylamine compounds. In the reaction, a benzylamine compound is used as a substrate, no solvent is used, oxygen is used as an oxygen source, a two-dimensional boron oxide alkene nanosheet is used as a catalyst, the reaction temperature is 80-100 DEG C, the reaction time is 10-30 hours, and the oxygen pressure is normal pressure. The catalytic system does not involve the introduction of any metal active center, the cost of the catalytic system is effectively reduced, the introduction of trace metal impurities in the product is avoided, and the two-dimensional boron oxide alkene nanosheet shows higher selectivity than other boron-based catalysts, shows higher catalytic activity than corresponding graphene oxide, and has a good application prospect. And compared with some current metal catalytic systems, the catalyst also has obvious catalytic activity advantage.

A glass composition comprises silicon dioxide, aluminum oxide, boron oxide, fluorine, a first component comprising calcium oxide, and a second component comprising zirconium dioxide and manganese oxide. Based on the total amount of 100 wt% of the glass composition, the content of silicon dioxide is 52 wt% to 62 wt%, the content of aluminum oxide is 8 wt% to 13 wt%, the content of boron oxide is 19 wt% to 31 wt%, and the content of fluorine is gt; 0 wt% and 2 wt% or less; the glass composition optionally contains zinc oxide, and if the glass composition contains zinc oxide, the zinc oxide content is gt; 0 wt% and lt; 0.25 wt%; the glass composition simultaneously satisfies the following formulas: [I] M + X < = 4.5, [II] and [III] M = manganese oxide content, X = first component content, A = alumina content, S = silica content, B = boron oxide content, and Y = second component content. The glass composition has low dielectric properties, good structural stability, a laddered window and uniformity. The invention also provides a glass comprising the glass composition, a glass fiber comprising the glass composition, and an article comprising the glass fiber.

The invention relates to a method for synthesizing calcium hexaboride micro-nano powder by electric field and magnetic field coupling auxiliary combustion, which mainly comprises the following steps: by taking calcium hydroxide, boric oxide and magnesium powder as raw materials, carrying out electric field and magnetic field coupling auxiliary combustion synthesis to obtain a reaction product; and then, carrying out acid pickling on a reaction product to obtain the unique calcium hexaboride micro-nano material with the hollow cubic structure. In the process of combustion synthesis of calcium hexaboride, under the coupling influence of an electric field and a magnetic field, the prepared calcium hexaboride micro-nano powder shows unique hollow cubic structural characteristics, and the structural characteristics enable the calcium hexaboride micro-nano powder to have the advantages of high specific surface area, light weight, porous neutron absorption and the like; the method has important application prospects in the fields of aerospace, high-end manufacturing, nuclear industry and the like.

Disclosed are lithium borosilicate compositions consisting essentially of a system of lithium oxide in combination with silicon oxide and boron oxide, wherein the lithium borosilicate comprises between 70 and 83 atomic percent lithium based on the total atomic percent of lithium, boron and silicon, and wherein the lithium borosilicate is a glass.

To develop a composite of a new constitution containing a powder having a radiation shielding function in a high content.SOLUTION: Molten aluminum is impregnated and filled into all voids of a preform made of a mixture containing one or more kinds of radiation shielding powders selected from gadolinium oxide, boron carbide, boron oxide, boron, barium sulfate, strontium oxide, tungsten, tungsten oxide, tungsten carbide, molybdenum, molybdenum oxide, iron powder, iron oxide powder, and ferrite powder and a liquid silica-based binder, the mixture containing the radiation shielding powders in a range of 3 to 85% in total; In the composite body having the radiation shielding function and the method for manufacturing the same, a liquid organic-inorganic sealing agent is impregnated and solidified to form the composite body, and a liquid silica-based binder has characteristics capable of forming a preform at a temperature at which the radiation shielding powder is not decomposed.SELECTED DRAWING: None

The invention relates to the field of hydrogenation catalysts, and discloses a Pd-containing catalyst and a preparation method and application thereof, the catalyst comprises an alumina carrier and a Pd active component; based on the total mass of the catalyst, the mass percentage content of the Pd active component is 0.1-0.5 wt%; the alumina carrier comprises alumina and boron oxide; the alumina carrier comprises alpha-Al2O3, and the grain size of a 113 crystal face perpendicular to the alpha-Al2O3 is not more than 25 nm. The grain size of alpha-Al2O3 in the alumina carrier of the Pd-containing catalyst is small, so that the number of active centers of the catalyst is increased, and the hydrogenation activity is improved.

Described are boron oxide-containing adsorbents that include porous adsorbent base and boron oxide on surfaces of the base, as well as devices that include the boron oxide-containing adsorbent, and related methods of preparing and using the boron oxide-containing adsorbent.

The present application relates to a kind of sodium sulfate iron composite sodium ion positive electrode material and its preparation method and battery, belong to sodium battery technical field, to solve at least one of the problems such as the poor air stability and conductivity of the sodium sulfate iron positive electrode material prepared by the existing method, easily lead to the capacity and cycle stability of battery is low, limit the application of sodium sulfate iron positive electrode material in sodium ion battery.The inner layer of the sodium ion positive electrode material of the present application is boron oxide coated sodium sulfate iron, the middle layer is boron-carbon nanotube transition layer, the outer layer is carbon nanotube coated sodium sodium pyrophosphate phosphate, boron-carbon nanotube transition layer is formed by the covalent bonding reaction of boron oxide and the functional group of CNTs after high-temperature induced decomposition of boric acid, double optimization is carried out in the interface combination and conductivity, improve the ion conductivity of sodium ion positive electrode material, the capacity of positive electrode material, rate and cycle performance, especially air stability.

The present invention provides diatomaceous earth and borosilicate glass having a high refractive index, low density, and high transmittance to blue light. [Solution] It contains silicon dioxide (SiO2) and / or boron oxide (B2O3) as a glass-forming agent and has a refractive index n of 1.80 or higher when measured at 587.56 nm. d And, when measured at 25℃, it was 5.5 g / cm³. 3 A glass is provided having the following density and, in particular, high transmittance to blue light. Optionally, the glass may be characterized by high transmittance in the visible and near-ultraviolet (near-UV) ranges of the electromagnetic spectrum, and / or good glass-forming properties.

The invention relates to a device and method for preparing boric acid from a boron trifluoride-methyl ether complex, the device comprises a steam generator, a gasification device and a reactor, and the steam generator and the gasification device are gathered through a pipeline and then connected with the reactor; the steam generator is used for producing steam; and the gasification device is used for producing a gas boron trifluoride-methyl ether complex. The method for preparing boric acid comprises the following steps: step 1, air replacement; step 2, preheating; 3, enabling water vapor to react with the boron trifluoride-methyl ether complex in a reactor to obtain a primary product; and step 4, after the reaction is completed, continuously keeping the temperature. The boron trifluoride-methyl ether complex reacts with water vapor at high temperature, boron oxide is obtained through a one-step method, the technical route is greatly simplified, the yield of boron is increased, and production energy consumption is reduced.

This invention provides an alumina inert coating for silicon-based ceramic cores. The alumina inert coating is made from the following raw materials in parts by weight: 20-35 parts alumina composite ceramic powder and 65-80 parts coating additives; the alumina composite ceramic powder is made from the following raw materials in parts by weight: 86-100 parts alumina powder, 0.1-4 parts mineralization modifier, and 0.1-10 parts modified sintering aid. The alumina inert coating of this invention uses alumina as the coating material matrix, effectively isolating the silicon-based ceramic core matrix from the high-temperature alloy during the casting process. This significantly prevents interfacial reactions between the alumina and the high-temperature alloy during ceramic core casting, contributing to the dimensional accuracy of hollow turbine blades. The introduction of boron carbide, which is oxidized during high-temperature sintering to generate boron oxide, promotes the sintering process, making the material denser, reducing porosity, and further improving the strength and toughness of the ceramic core.