309 results about "Argon atmosphere" patented technology

The invention provides a high-stability lithium-rich manganese-based positive electrode material and a preparation method thereof, and relates to the technical field of lithium-rich manganese-based positive electrode materials, and the method comprises three steps of preparation of a homogeneous precursor, solid-state mechanical fusion doping and coating, and high-temperature sintering; a lithium-rich manganese-based precursor is prepared by adopting a homogeneous coprecipitation process, uniform distribution of metal ions is ensured, then an aluminum source, a zirconium source and a fluorine source are introduced as doping agents, phosphate and a titanate coating agent are combined, doping and coating integrated treatment is realized through mechanical ball milling, and the lithium-rich manganese-based composite material is obtained. And finally, mixing with a lithium source in an argon atmosphere, and carrying out high-temperature sintering of temperature programming and staged heat preservation to form a stable composite coating layer in situ. Therefore, manganese ion migration is effectively inhibited through lattice doping, a layered structure is prevented from being converted into spinel or rock salt phase, meanwhile, a nanoscale ion / electron transmission channel is constructed, interface impedance is reduced, and the charging and discharging efficiency under high voltage is improved.

The application discloses a kind of derived biomass hard carbon material pulverization process, belong to biomass charcoal material processing technical field, first, pulverization process includes the following steps: after drying, the coconut shell derived hard carbon block is carried out primary crushing, while spraying first modifier, obtain the particle size 1~3mm of coarse crushing modified particle;Coarse crushing modified particle is carried out secondary precision crushing under argon atmosphere, while spraying second modifier, obtain the precision crushing modified particle of D 50 Particle size is 15 μm;Precision crushing modified particle is carried out roll grinding spheroidization, while spraying third modifier, obtain the spherical modified particle of D 50 Particle size is 10 μm;Spherical modified particle is carried out flash drying after cooling, then add magnesium stearate to it, after mixing, obtain derived biomass hard carbon material.Then, the application realizes breakthrough in tap density, particle size distribution, first efficiency and other core indexes by the coordination of three-stage gradient modification and progressive pulverization process.

The invention discloses preparation of a high-performance carbon matrix embedded iron-based catalyst based on a metal organic framework precursor and application of the high-performance carbon matrix embedded iron-based catalyst in reverse water-gas shift reaction. In the preparation process, commercially available 1, 3, 5-trimesic acid iron (the chemical formula is C9H3FeO6, abbreviated as Fe-BTC) is selected as a raw material, pyrolysis treatment is carried out in an argon atmosphere, then air passivation is carried out, and finally the high-performance carbon matrix embedded iron-based catalyst based on the metal organic framework precursor is successfully prepared. The MOF-600 has excellent performance in many catalysts, the carbon dioxide production rate reaches 24.0 mmol CO.gcat <-1 >. S <-1 > at the temperature of 400 DEG C in a reverse water gas shift reaction, the performance is remarkably superior to that of an existing non-noble metal catalyst, and extremely high catalytic efficiency and application potential are shown.

The invention relates to the technical field of waste resourceful treatment, in particular to a sponge titanium weight bottom skin crushing and impurity removing method which comprises the following steps of peeling, bottom skin brake cutting, water jet cutting and crushing, acid leaching and impurity removing, ultrasonic cleaning, argon drying and screening and recycling. The bottom skin is crushed into small-granularity particles by adopting a cross grid water jet cutting technology, metal impurities such as Fe and Ni are removed in combination with acid leaching treatment, residual impurities are removed through multi-stage ultrasonic cleaning, oxidation discoloration is avoided through argon atmosphere drying, and meanwhile water jet sand is recycled; in the process, key indexes such as brake cutting pressure, cutting parameters, acid leaching time and ultrasonic frequency are accurately controlled through a quantification formula. The method effectively solves the problems that equipment is easy to damage during crushing and impurities are difficult to remove in a traditional process, remarkably improves the grade of bottom leather materials, widens the downstream application range, improves the resource utilization rate and economic benefits, and is suitable for industrial batch production.

The preparation method of the Ni-Mn bimetallic oxide modified magnesium-based hydrogen storage composite material comprises the steps that 1, under the protection of an argon atmosphere, pure magnesium powder is placed in a reaction kettle, and a product MgH2 is obtained; step 2, dissolving nickel nitrate hydrate and manganous nitrate hydrate in absolute ethyl alcohol, adding urea into the mixed solution, continuously stirring at room temperature, and then carrying out constant-temperature reaction in a tetrafluoropolyvinyl chloride high-pressure reaction kettle in a drying oven; after the reaction is finished, cooling to room temperature, and carrying out centrifugal washing; supernate obtained after centrifugal washing is poured out, precipitates are reserved and transferred into a vacuum drying box, and vacuum drying is conducted; grinding a block obtained after drying, and transferring the block into a tubular furnace for heat treatment to obtain a bimetallic oxide NiMn2O4; 3, MgH2, NiMn2O4 and stainless steel ball milling beads are weighed and put into a mechanochemical reaction ball milling kettle, intermittent ball milling is conducted for a certain time under the protection of a specific atmosphere, and then a composite sample MgH2-NiMn2O4 is collected. The practical application benefit of the magnesium-based hydrogen storage technology can be greatly improved.

The application discloses a high-performance stainless steel-based electrolytic water dual-function electrode and application thereof, and the electrode is prepared through the following steps: step 1, pretreating a stainless steel surface to remove impurities on the surface; step 2, placing the stainless steel obtained after the treatment in step 1 and a phosphorus source in an argon atmosphere under the condition of 350-450 DEG C, phosphorizing the stainless steel for 1-3 hours to obtain a phosphorized stainless steel electrode, wherein the linear distance between the phosphorus source and the stainless steel is kept at 5-10 cm; and step 3, placing the phosphorized stainless steel electrode obtained after the treatment in step 2 in a RuCl3 solution, and performing electrodeposition on the phosphorized stainless steel as a cathode to obtain the electrode, wherein the concentration of the RuCl3 solution is 2-8 mmol / L, the potential window during the electrodeposition is-2 V-0 V, and the electrodeposition time is 15-25 cycles.

The invention relates to the technical field of preparation of silicon carbide ceramics, in particular to an in-situ reaction sintered silicon carbide ceramic and a preparation method thereof.The preparation method comprises the following technological stages which are conducted in sequence: S1, preparation of silicon carbide slurry, specifically, organic matter precursor raw materials are weighed according to the mass content percentage to form the silicon carbide slurry; s2, vacuum grouting: injecting the silicon carbide slurry in the vacuum grouting tank into the shaping mold from the bottom of the shaping mold to form a silicon carbide green body; and S3, in-situ reaction sintering is conducted, specifically, the silicon carbide green body is placed in a sintering furnace, heating, heat preservation and cooling are conducted on the silicon carbide green body in the argon atmosphere through a segmented temperature control technology, and the silicon carbide ceramic is obtained. The silicon carbide ceramic prepared by the method disclosed by the invention has relatively high density and excellent mechanical properties.

The invention relates to an easy-to-prepare low-cost high-performance sodium ion battery hydrogen peroxide modified hard carbon negative electrode material, and a preparation method comprises the following steps: S1, crushing alfalfa, cleaning, filtering, and carrying out vacuum drying to obtain a biomass precursor material; s2, performing low-temperature cracking, and annealing in an argon atmosphere to obtain a hard carbon precursor carbon material; s3, completely dispersing the hard carbon precursor material in the step S2 in deionized water to obtain a hard carbon precursor material mixed solution, dropwise adding an acid solution to adjust the pH value, then dropwise adding a hydrogen peroxide aqueous solution, filtering and washing to be neutral after reaction to obtain an intermediate product, and performing vacuum drying to obtain a modified hard carbon precursor carbon material; and S4, performing high-temperature pyrolysis and annealing under the protection of an argon atmosphere. The biomass alfalfa is used as a main raw material, and compared with a hard carbon negative electrode material prepared from a traditional biomass material, the specific capacity, the first coulombic efficiency and the capacity retention rate are remarkably improved.

The invention belongs to the technical field of powder metallurgy, and particularly relates to a high-fluidity MIM metal feed and a forming process thereof.The high-fluidity MIM metal feed is composed of the following materials: metal powder: spherical metal powder (a titanium alloy TC4 material), polycaprolactone and graphene nanosheets; wherein the volume ratios are 68-72 vol%, 0.5-2 wt% (based on the mass of the metal powder) and 0.1-0.5 wt% (based on the mass of the metal powder) respectively; a powder oxide layer is removed through vacuum plasma cleaning (300-500 W, argon atmosphere), a metal core-PCL / graphene shell structure is prepared in combination with ultrasonic-assisted in-situ polymerization, lubrication and adhesion enhancement are synchronously achieved, the powder oxygen content is controlled to be smaller than 500 ppm, and sintering oxidation defects are reduced.

The invention belongs to the related technical field of two-dimensional materials, and discloses a two-dimensional degenerate semiconductor film material and a preparation method and application thereof, and the preparation method comprises the following steps: S1, uniformly spin-coating a niobium salt compound solution on a substrate; and S2, based on the obtained substrate, preparing the two-dimensional degenerate semiconductor film material by adopting a chemical vapor deposition method, specifically, in a tubular furnace with an argon atmosphere, placing a sulfur source or a selenium source at the reaction upstream, placing a molybdenum foil in a sleeve in the tubular furnace and in the reaction midstream, and placing the substrate at the reaction downstream, so as to obtain the two-dimensional degenerate semiconductor film material. And introducing oxygen midway, and heating to a reaction temperature to generate the two-dimensional degenerate semiconductor film material. According to the method, the uniformly-covered precursor substance is formed on the surface (substrate) of the two-dimensional material through the spin-coating process, a high-temperature vacuum environment and complex equipment are not needed, modification and polarity regulation and control of the material can be completed only by regulating and controlling the concentration of the precursor solution, the spin-coating rotating speed and the spin-coating time, and low-cost batch processing can be achieved.

The invention provides a method for simulating the influence of montmorillonite clay mineral water on organic matter pyrolysis hydrocarbon generation, and belongs to the technical field of organic matter pyrolysis. The method comprises the following steps: heating montmorillonite to obtain dehydrated montmorillonite, mixing organic matters and the dehydrated montmorillonite in an argon atmosphere and a dry environment, transferring a mixed sample into a gold tube, and loading the sample; putting the gold tube into an iron reaction kettle, filling the reaction kettle with water, and cooling after heating reaction; putting the cooled gold tube into a gas collecting device, and calculating the amount of substance of gas according to an ideal gas state equation; the collected gas is subjected to GC analysis to obtain the percentage of each gas, the yield of each gas is calculated by combining the amount of substance of the gas, and the influence of the montmorillonite clay endogenous water on hydrocarbon generation by thermal decomposition of organic matters is evaluated. Under the condition that only the unified boundary condition of clay mineral water is changed, a verifiable judgment system of'endogenous water type-product spectrum characteristic-reaction channel 'is established for the first time.

The invention discloses a monatomic loaded lignin carbon-based photocatalyst as well as a preparation method and application thereof. The preparation method of the photocatalyst comprises the following steps: S1, grinding and blending lignin and melamine, then adding the mixture into water, transferring the obtained solution into a hydrothermal reaction container, reacting at 175-195 DEG C for 4-10 hours, and after the reaction is finished, cooling at room temperature, washing and centrifugally separating to obtain a solid mixture; s2, dispersing the solid mixture in an aqueous solution containing metal salt, stirring at room temperature, and drying after the reaction is finished; and S3, putting the dried solid into a container, putting the container into a pyrolysis reactor, heating to 800-1000 DEG C in an argon atmosphere, pyrolyzing for 2-6 hours, and naturally cooling to obtain the monatomic loaded lignin carbon-based photocatalyst. The monatomic loaded lignin carbon-based photocatalyst provided by the invention can efficiently catalyze glucose to synthesize glucaric acid under mild conditions, and the obtained target product is relatively high in yield and easy to separate, and has a very good industrial application prospect.

This invention relates to the field of ferroalloy smelting technology and discloses a high-carbon ferromanganese and its preparation method, comprising the following steps: raw material pretreatment; converter preheating and bottom material laying: pretreated high-grade manganese ore, lime, and coke powder are mixed and added as bottom material to the CLU converter for preheating; iron addition and initial reduction: high-carbon ferromanganese is added to the converter, and graphite fragments are added, and initial reduction is carried out under a pure argon atmosphere; atmosphere control and second-stage reduction: when the carbon content of the molten iron drops to 5.0-5.8%, the reblowing gas is switched to a mixed gas of argon, CO, and CH4, and the remaining high-grade manganese ore, silicon carbide, ferrosilicon manganese alloy, and supplementary coke powder are added in batches, while adjusting the slag composition; endpoint judgment and iron tapping. The high-carbon ferromanganese of this invention has precise composition and high purity, and the preparation method is characterized by high efficiency, low consumption, greenness, and high manganese recovery rate, enabling the industrial-scale production of high-carbon ferromanganese.

The application discloses a method for preparing a carbon-carbon heater by means of pitch impregnation, and the carbon-carbon composite material prepared through the process steps of preform preparation, pitch impregnation and solidification, high-pressure pitch impregnation, low-temperature carbonization, repeated impregnation and carbonization and high-temperature graphitization has the advantages of high density and low resistivity, and the photovoltaic single crystal furnace heater is further machined. First, micron composite powder of boron carbide-tungsten carbide is uniformly applied on the surface of the heater and is subjected to high-temperature treatment, so as to form a dense ceramic coating, and then a mixed pyrolytic graphite layer is deposited in a methane-argon atmosphere, and through the above two coating processes, the silicon vapor corrosion resistance of the carbon-carbon heater is significantly enhanced, so that the service stability and service life of the carbon-carbon heater are improved.

The invention discloses a flocculent vanadium-doped MoN / CNT composite material and a preparation method and application thereof.The method comprises the steps that 1, ammonium molybdate is added into absolute ethyl alcohol to be dissolved, and a solution A is obtained; 2, adding 2-methylimidazole into deionized water, and dissolving to obtain a solution B; 3, adding the solution A into the solution B, stirring, carrying out suction filtration, separating out a precipitate, and drying to obtain a precursor I; 4, adding the precursor I into deionized water, and stirring to obtain a turbid solution; 5, ammonium metavanadate and polyvinylpyrrolidone are added into absolute ethyl alcohol, and a solution C is obtained; 6, adding the solution C into the turbid solution, stirring, carrying out suction filtration, separating out a precipitate, and drying to obtain a precursor II; 7, performing low-temperature sintering on the precursor II in an argon atmosphere to obtain a precursor III; and 8, mixing the precursor III with urea, and performing high-temperature sintering in an argon atmosphere to obtain the vanadium-doped MoN / CNT composite material which has high energy density and high conductivity and can endow an energy storage device with high rate capability and long cycle life.

The invention relates to the technical field of alloy shaped charge liners for perforating bullets, and particularly discloses an energy-releasing alloy shaped charge liner for a perforating bullet and a preparation method of the energy-releasing alloy shaped charge liner for the perforating bullet to solve the problems that when an alloy shaped charge liner is prepared through an existing Zr-Ti-Nb composite material system, a blank is prone to expanding and cracking, and the dynamic tensile property of a product is insufficient. Comprising the following steps: S1, respectively taking zirconium powder, niobium powder, titanium powder and TiH2 powder, and mixing to obtain a premix; s2, taking the premix, and performing dry bag static pressure to obtain a dry bag static pressure blank; s3, the dry bag static pressure blank is taken and subjected to stepped hydrogen control sintering, and a hydrogen control sintering blank is obtained; s4, the hydrogen-controlled sintered blank is taken and placed in an argon atmosphere, heating and pressure sintering are conducted, and a hot isostatic pressing sintered blank is obtained; and S5, the hot isostatic pressing sintered blank is subjected to oil quenching at the temperature of 1050 + / -50 DEG C, and the energy release alloy shaped charge liner for the perforating bullet is obtained. And meanwhile, multiple processes such as oil quenching heat treatment are combined, the energy-releasing alloy shaped charge liner of the full-beta-phase structure can be stably obtained, and the effects such as the sneaking effect and the chambering effect can be achieved on the premise that the penetrating depth of a perforating bullet is not reduced.

The invention discloses a silicon-oxygen-carbon-based negative electrode material and a preparation method thereof, and belongs to the technical field of lithium battery negative electrode materials, and the preparation method comprises the following steps: (1) mixing alcohol, water and acid to prepare an acid solution with the pH value of 2-4, adding organosiloxane into the acid solution, and stirring in a water bath to obtain a siloxane hydrolysate; (2) adding a pyrene compound into the siloxane hydrolysate, and carrying out ultrasonic treatment; (3) adding alkali, stirring in a water bath at 20-50 DEG C for 1-3 hours, and then freeze-drying to obtain a precursor of SiOC; and (4) placing the precursor in an atmosphere furnace, sintering in an argon atmosphere, and naturally cooling to obtain the modified negative electrode material SiOC. The amorphous carbon content of the prepared SiOC is increased, on one hand, the electronic conductivity of the SiOC can be improved, and on the other hand, volume expansion in the charging and discharging process can be relieved.

The invention belongs to the nuclear industry and can be used for the production of fuel pellets from uranium-molybdenum metal powder enriched with uranium-235 to 7%, which can be used as fuel elements for nuclear reactors. The sintering of the pellets is carried out in an inert argon atmosphere at a temperature in the range of 1100°C to 1155°C, as the initial powder, a particle size of 160 μm is used, with a molybdenum content of 9.0 to 10.5 wt.%. The powder is preheated at a temperature of 500°C for 10-20 hours (in an argon medium), and then cold-pressed into pellets in a mold at a pressure of up to 950 MPa. According to another method, when preparing uranium-molybdenum pellets using a binder (plasticizer), the pellets are heated in argon from 300°C to 450°C for a duration of 2-4 hours before sintering, in order to remove the binder. The invention allows to increase the uranium content in the fuel, to reduce the heat accumulated in the core of the nuclear reactor, and to reduce the energy release in the event of a violation of the normal operating conditions of the nuclear reactor, which will improve its safety and emergency stability.

The invention relates to an Au / Ag / g-C3N4 composite material and a preparation method thereof.The preparation method comprises the steps that urea, silver nitrate and HAuCl4 are added into a clean beaker and tightly wrapped with tinfoil, deionized water is added for dissolution, and then magnetons are added and stirred on a magnetic stirrer in a dark place till the magnetons are completely dissolved; drying the mixture solution in a drying oven, grinding the mixture solution into powder by using an agate bowl after the mixture solution is completely dried, and putting the powder into a corundum porcelain boat; the preparation method comprises the following steps: performing thermal polymerization treatment on a mixed grinding material of urea, silver nitrate and HAuCl4, heating a tubular furnace to 540 DEG C under the protection condition of argon flow, keeping the constant temperature for 1-3 hours, and finally cooling the tubular furnace to room temperature in an argon atmosphere environment to obtain the Au / Ag / g-C3N4 composite material. Au and Ag are introduced to weaken hydrogen bonds in carbon nitride, so that the technical problem that future application of existing g-C3N4 is limited by specific surface area, insufficient visible light absorption and carrier recombination is solved.

The invention relates to the technical field of preparation of lithium ion battery positive electrode materials, in particular to a method for regulating and controlling a high-exposure {010} crystal face of a manganese-rich phosphate-based positive electrode material, which comprises the following steps: weighing manganese salt (MnO2, MnC2O4. 2H2O, MnCO3, Mn (H2PO4) 2, MnC4H6O4. 4H2O and the like), ferric salt (FeSO4. 7H2O, Fe2O3, FePO4 and the like), lithium salt (LiOH, Li2CO3, CH3COOLi, LiH2PO4 and the like), phosphate (NH4H2PO4) and sulfate (MgSO4, NaSO4, FeSO4. 7H2O and the like) according to the molar ratio of (1-n): n: 1: 1: 0.01 (n = 0.4, 0.5, 0.6 and 0.7), adding 10-50% of organic drying at the temperature of 80-110 DEG C to obtain a precursor; putting the precursor into a tubular furnace, presintering for 2-5 hours at the temperature of 300 DEG C in an argon atmosphere, and then naturally annealing; and heating to 700 DEG C, sintering for 6-10 hours in an argon atmosphere, and naturally annealing to obtain the lithium manganese iron phosphate positive electrode material with the highly exposed {010} crystal face. After the highly-exposed {010} crystal face material LiMn0. 6Fe0. 4PO4 prepared by the method disclosed by the invention is circulated for 300 times at a high rate of 5C, the specific discharge capacity retention rate is as high as 95.7% and is far higher than 50.4% of that of an unmodified control sample.

The invention discloses a liquid-phase indirect preparation method of high-purity lithium sulfide, and belongs to the field of fine chemical engineering. The preparation method comprises the following steps: firstly, enabling metal lithium to react with high-purity naphthalene at low temperature in an ether solvent in an anhydrous oxygen-free argon atmosphere to generate naphthyl lithium; then introducing high-purity hydrogen sulfide and a naphthyl lithium carrier to react at room temperature to generate lithium hydrosulfide; then converting at 100-150 DEG C to generate lithium sulfide; and cooling, filtering in an argon atmosphere, washing with an ether solvent, and carrying out vacuum drying to obtain high-purity finely-dispersed lithium sulfide with the purity of more than 99.99%. Compared with the prior art, the lithium sulfide obtained by the preparation method disclosed by the invention is powder which is high in purity, uniform in granularity, fine in dispersion and relatively good in flowability, is stable in process and product quality, can be suitable for industrial-scale production of high-purity lithium sulfide, and has a very good popularization and application value.

The invention relates to the technical field of energy storage batteries, in particular to a porous zinc-tin composite foil, a lithium ion negative electrode, a preparation method of the lithium ion negative electrode and a lithium metal total battery. The preparation method of the porous zinc-tin composite foil comprises the following steps: mixing tin powder and sodium chloride, and carrying out ball milling; filling the tin powder into foamed zinc, heating to melt and recrystallize the tin powder in a three-dimensional framework of the foamed zinc into a whole, and rolling; putting into an argon atmosphere, and heating to form a zinc-tin alloy; and putting into water to remove sodium chloride particles inside. The lithium metal is induced into the internal holes of the three-dimensional porous zinc-tin composite foil for deposition, so that nucleation and growth of lithium dendrites are inhibited, and the cycle stability of the battery is improved.

The application discloses a precious metal embedded porous carbon coated honeycomb ceramic monolithic catalyst and application thereof. The liquid phenolic resin polymer containing chloroplatinic acid is uniformly coated on the surface of the cordierite honeycomb ceramic through impregnation treatment; in an oxygen-nitrogen mixed atmosphere, one-stage solidification makes the liquid phenolic resin polymer containing chloroplatinic acid coated on the surface of the cordierite honeycomb ceramic completely solidified; two-stage calcination makes oxygen react with chloroplatinic acid, so that the chloroplatinic acid is decomposed, and the negative influence of chloride ions on the catalyst is eliminated; in an inert gas argon atmosphere, carbonization makes the phenolic resin polymer carbonize under high-temperature conditions to form porous carbon, and meanwhile, platinum ions are reduced to platinum single elements and embedded by the porous carbon, so that the precious metal (platinum, iridium) embedded porous carbon coated honeycomb ceramic monolithic catalyst is finally prepared.

The invention discloses a preparation method of homogeneous high-purity scandium-aluminum alloy powder, and belongs to the technical field of alloy material preparation. The method comprises the following steps that metal scandium and aluminum metal ingots are prepared according to the atomic ratio of scandium to aluminum being 1: 3-3: 1 and then placed into a smelting furnace, and smelting and heat preservation are conducted under the argon atmosphere; the alloy solution is poured into a rotary water-cooling copper roller with the linear speed of 2-5 m / s to achieve rapid hardening, and a scandium-aluminum alloy sheet is prepared; the scandium-aluminum alloy sheet is activated and then subjected to hydrogenation-dehydrogenation treatment; and finally, xenon is used as working gas for airflow pulverization, and scandium-aluminum alloy powder of 10-75 microns is obtained through airflow separation. According to the method, the polycrystalline alloy sheet with fine grains is prepared through rapid hardening, hydrogen decrepitation is promoted through the grain boundary, pollution of a ball milling medium is avoided, the problems that in the prior art, alloy powder is low in purity, uneven in grain size and low in crushing yield are solved, and the prepared alloy powder is homogeneous, high in purity and suitable for preparation of high-end products such as target materials.

The application provides a coal-based active coke, a structure directional regulation and control method and application. The application uses low-cost shaped coal-based active coke as raw material, reduces the oxygen content of the reduced active coke powder through particle size refinement and reduction treatment, and then controls the multi-scale structure of the reduced active coke powder through ball milling treatment in an air atmosphere, an argon atmosphere or a carbon dioxide atmosphere. The regulation and control method can obtain a high-performance carbon-based electrocatalyst with reduced amorphous carbon lattice size, rich edge defects, different oxygen doping concentrations and developed mesoporous structure. The overall process flow is simple to operate, no waste gas and waste liquid are generated, and the method has the potential for large-scale production and wide commercialization. In addition, the raw material used in the application is coal-derived shaped active coke, and active cokes developed from different types of coal can be used as raw materials, so that the material source is relatively wide and the cost is extremely low.

The invention is suitable for the technical field of catalysts for hydrogen production through electrolysis of water, and provides a medium-entropy Prussian blue analogue derivative sulfide catalyst and a preparation method thereof.The preparation method comprises the following steps that Ni (NO3) 2.6 H2O and C6H5Na3O7. 2H2O are dissolved in deionized water, and a solution A is formed through magnetic stirring; dissolving K3 [Co (CN) 6] and K3 [Fe (CN) 6] in deionized water, and magnetically stirring to form a solution B; adding the solution B into the solution A, and stirring at room temperature to obtain a mixed solution; heating the mixed solution in a water bath and stirring; carrying out centrifugal treatment on the mixed solution, separating to obtain a precipitate, washing for multiple times, and carrying out vacuum drying overnight to obtain a FeCoNi-PBA precursor; the FeCoNi-PBA precursor and excessive sulfur powder are placed in two porcelain boats respectively, the two porcelain boats are placed on the downstream and the upstream of a tubular furnace, in the argon atmosphere, the temperature is increased, heat preservation treatment is conducted, and the medium-entropy sulfide named as FeCoNi-S is obtained. The bifunctional catalyst with rich defects and high specific surface area is prepared, and efficient and stable hydrogen production and oxygen production through water electrolysis are achieved.

The application discloses preparation of one-dimensional rare earth metal-organic framework, one-dimensional rare earth metal-organic framework loaded transition metal-organic framework material and preparation and application, relates to the technical field of one-dimensional nanowire RE-MOF material preparation and double-MOF composite core-shell structure preparation, and a preparation method comprises the following steps: synthesizing a series of RE-MOF precursor one-dimensional nanowires by a solvent thermal method; at room temperature, in a methanol solvent system, PVP is used as an inducer to promote Co 2+ Deposition and enrichment on the surface of the RE-MOF, and then nucleation and growth of a uniform TM-MOF shell layer are formed by the coordination of 2-methyl imidazole and Co 2+ , thereby obtaining a core-shell structure one-dimensional nanowire Co-MOF@RE-MOF material. Finally, the prepared series of core-shell structure one-dimensional nanowire materials are subjected to calcination treatment in an argon atmosphere, and a multi-component composite wave-absorbing material with good wave-absorbing performance is obtained.

The application relates to a nano cerium oxide reinforced biological magnesium alloy and a preparation method thereof, and belongs to the technical field of medical implant material preparation. The biological magnesium alloy is composed of a magnesium matrix, an aluminum-cerium phase and nano cerium oxide, and the preparation method is as follows: (1) nano cerium oxide and AZ61 magnesium alloy powder are mixed by ball milling under an argon atmosphere according to a designed proportion to obtain uniformly dispersed mixed powder; and (2) the above mixed powder is used as raw material to prepare the nano cerium oxide reinforced biological magnesium alloy by using a selective laser melting technology under an argon atmosphere. In the application, part of the nano cerium oxide is reduced into cerium by magnesium, the cerium combines with aluminum in the matrix to form an aluminum-cerium phase, magnesium-aluminum phase precipitation is inhibited, and micro-galvanic corrosion can be inhibited; meanwhile, the remaining nano cerium oxide falls off into a degradation product film after the magnesium matrix is degraded, the compactness of the product film is increased, the invasion of an erosion liquid is blocked, and the degradation resistance of the magnesium alloy is improved in a synergistic manner by inhibiting galvanic corrosion and increasing the compactness of the degradation product film.

This invention belongs to the field of new materials technology and discloses a Cu-Sn based solder for high-reliability welding joints and its preparation method. The preparation method includes: polishing, cleaning, and glow discharge sputtering the substrate to obtain a clean substrate; depositing a pure copper layer on the clean substrate surface using magnetron sputtering technology under argon atmosphere; simultaneously sputtering a copper target and a tin target to deposit a copper-tin co-sputtered layer on the pure copper layer surface; and sputtering a tin target to deposit a pure tin layer on the copper-tin co-sputtered layer surface, resulting in a Cu-Sn based solder with a multi-layer structure; in the copper-tin co-sputtered layer, the atomic ratio of Cu to Sn is 5-9:1. The preparation method of this invention is simple, pollution-free throughout, cost-effective, and improves efficiency; furthermore, the prepared Cu-Sn based solder can effectively reduce the Cu-Sn interdiffusion distance during transient liquid phase welding, reduce void formation, make welding more complete, and improve the reliability of the welding joint.

This invention discloses a near-space epitaxial method for significantly improving the uniformity of cadmium zinc telluride (CdZnTe) epitaxial films based on air-firing substrate treatment. The method involves air-firing a cleaned and dried gallium arsenide (GaAs) substrate at a predetermined temperature under argon atmosphere. The growth surface is calibrated before air-firing, and the GaAs substrate after air-firing exhibits a matte finish under optimal parameters. A CdZnTe polycrystalline block is used as the growth source. The polycrystalline block is trimmed to fit into the mask apertures and then subjected to grinding, ultrasonic cleaning, and air-firing to remove surface impurities and mechanical damage layers. During the film growth stage, appropriate growth parameters are set in a near-space sublimation furnace to allow CdZnTe to epitaxially grow on the GaAs substrate.