710 results about "Air atmosphere" patented technology

The invention discloses a synthesis method of amphiphilic quantum dots and application of the amphiphilic quantum dots in nano oil displacement, and belongs to the field of nano oil displacement. The synthesis method comprises the following steps: heating a mixture containing a carbon source and a nitrogen source in an air atmosphere for reaction, and centrifuging, filtering and drying a reaction product to obtain the amphiphilic quantum dots, the carbon source is selected from at least one of glucose, mannose, citric acid, lignin, chitosan and starch; the nitrogen source is selected from at least one of alkylamine, and the carbon chain length of the alkylamine is C6 to C12. The synthesis method is simple, heating of a high-pressure reaction kettle is not needed, the technological process is simple, and the method is suitable for large-scale industrial production; the series of amphiphilic carbon quantum dots show better solubility and higher absolute fluorescence quantum yield in water and various organic solvents.

The invention relates to a preparation method of Pt monatomic nano-enzyme and application of Pt monatomic nano-enzyme in cardiac troponin I. The preparation method comprises the following steps: 1) ultrasonically dispersing cobalt salt, selenium powder, chloroplatinic acid, urea and sodium chloride in an alcohol solvent, heating and stirring until the solvent is completely volatilized to obtain a solid mixture, and grinding the solid mixture into powder; and 2) placing the powder in a heating device, carrying out Joule heat treatment in an air atmosphere, washing a reactant, and carrying out vacuum drying to obtain the Pt monatomic nano-enzyme. Se doping is introduced in the one-step chemical reaction process to construct oxygen vacancies, rapid heating and structural shaping are achieved in combination with Joule heat treatment, the Se-doped Co3O4-loaded Pt monatomic catalyst is obtained, the oxygen vacancies and Se doping sites are synergistically used as anchoring sites, Pt monatomic atoms are effectively fixed, and the loading capacity and dispersity of the Pt monatomic atoms are improved. The obtained material shows excellent POD-like enzyme activity, can be used for constructing a high-sensitivity colorimetric immunoassay system, and realizes rapid and accurate detection of cTnI.

The invention belongs to the technical field of sodium ion battery hard carbon negative electrode materials, and particularly relates to a phenolic resin asphalt super-crosslinking hard carbon composite active material and a preparation method and application thereof.The preparation method comprises the steps of phenolic resin precursor synthesis, oxidized asphalt precursor synthesis, super-crosslinking reaction and stepped carbonization; the preparation method comprises the following steps: reacting phenol with formaldehyde under the action of a catalyst to obtain a phenolic resin precursor; pre-oxidizing the coated asphalt in an air atmosphere to generate an asphalt precursor; the preparation method comprises the following steps: mixing a phenolic resin precursor with an asphalt precursor, adding an acid catalyst into an organic solvent, and performing reflux heating to form a chemically bonded three-dimensional cross-linked network structure; and sequentially carrying out low-temperature pre-carbonization and high-temperature carbonization in an inert gas atmosphere to obtain a target product, namely the hard carbon composite material. The target product provided by the invention has rich closed pore and multistage through pore structure hard carbon, and the sodium storage capacity of the hard carbon material is effectively improved.

The invention discloses a preparation method for selectively oxidizing thioether into sulfoxide through photo-initiation, and belongs to the field of synthesis of medical compounds. The preparation method comprises the following steps that in the air atmosphere, a thioether compound is dissolved in an acetonitrile-water mixed solvent, inorganic metal salt catalysts such as ferric chloride and copper sulfate are added, the mixture reacts for 8-48 h at the temperature of 0-45 DEG C under illumination with the wavelength of 295-405 nm, selective oxidation is carried out, and the sulfoxide product is obtained, and the molar ratio of thioether to the catalysts is 5: 1. The method overcomes the problems of excessive oxidation risk, complicated operation, environmental pollution and the like caused by dependence of a noble metal catalyst and use of a strong oxidant in the existing thioether oxidation method, has the advantages of high catalytic efficiency, high yield and excellent selectivity, can greatly reduce the production cost, is suitable for later industrial synthesis and amplification, and has wide application prospects. The method has the advantages of no expensive metal catalyst or oxidant, simple preparation process, high efficiency, environmental protection, safety and cost saving.

The invention relates to the technical field of cement-based material preparation, and particularly discloses a preparation method of an anti-carbonization all-solid waste slag-sulphoaluminate cementing material, which comprises the following steps: (1) putting a wet material formed by lead-zinc tailing powder and water into a reaction container, sealing, and heating; and mixing the obtained product with iron powder and / or iron oxide powder and water, stirring, separating out a solid product, and heating and drying in an air atmosphere to obtain the anti-carbonization tailing powder. And (2) mixing the anti-carbonization tailing powder with sulphoaluminate cement powder, and carrying out mechanical grinding treatment to obtain the modified sulphoaluminate cement. And (3) uniformly mixing blast furnace slag powder, the modified sulphoaluminate cement, fly ash, waste gypsum powder, an alkali activator, gypsum and a water reducing agent serving as raw materials to obtain the cementing material. According to the invention, the resource utilization of industrial solid waste is realized, the carbonization resistance of the cementing material is effectively improved, and the service durability of the cementing material is improved.

The invention relates to a sunken porous magnetic alloy ball wave-absorbing material and a preparation method and application thereof.The wave-absorbing material is prepared through the following steps that S1, citric acid, soluble ferric salt, soluble cobalt salt and soluble nickel salt are dissolved in a mixed solvent of ethylene glycol and water, and the mixture is fully stirred to form a uniform mixed solution; and S2, the mixed solution obtained in the step S1 is subjected to spray drying, obtained precursor powder is placed in the air atmosphere to be calcined to remove the carbon source, then the precursor powder is placed in the H2 / Ar atmosphere to be subjected to heating reduction, and the porous FeCoNi alloy balls with the surface pits are obtained and are the target product. The surface of the prepared alloy microsphere has an obvious concave structure, magnetic anisotropy and magnetic performance are enhanced, a small number of pores are generated in the reduction process, impedance matching of the material is optimized, and effective high-frequency electromagnetic absorption is achieved; and due to the synergistic effect of the recesses and the pores, the obtained alloy microspheres have obvious lightweight characteristic, and have good application prospects in the field of electromagnetic absorption.

The invention discloses a preparation method of low-carbon-content high-purity quartz sand, which comprises the following steps: carrying out alkaline hydrolysis and drying on organosilane to obtain alkaline xerogel, putting the alkaline xerogel into a quartz tube of a rotary tube furnace, starting the furnace body, adjusting the rotation rate, heating to a specific low temperature, and introducing nitrogen to replace air; introducing oxygen, controlling the pressure, carrying out oxidation reaction, relieving the pressure to normal pressure after the reaction, pumping and discharging the product, and repeating the oxidation and pumping steps for many times until the tail gas carbon dioxide reaches the standard; raising the temperature, introducing chlorine-containing gas for purification, finally raising the temperature to a sintering temperature, and sintering in an air atmosphere to obtain the low-carbon-content high-purity quartz sand. According to the preparation method, the energy consumption and the equipment cost of the carbon removal procedure are greatly reduced, the specific surface area and the densification performance of the subsequent high-purity quartz sand product can be guaranteed, and a technical path which is low in energy consumption, high in efficiency and capable of giving consideration to the product performance is provided for industrial preparation of the high-purity quartz sand through a sol-gel method.

The invention belongs to the technical field of catalytic materials and hydrocarbon reforming, and particularly relates to a high-entropy catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing a metal salt solution containing lanthanum, chromium, copper, zinc, manganese, nickel, iron and cobalt ions with a chelating agent and a dispersing agent for reaction, carrying out ultrasonic cavitation treatment to obtain sol, adjusting the pH value, gelatinizing under an oil bath heating condition to obtain a colloidal precursor, drying, and calcining in an air atmosphere to obtain a perovskite type high-entropy oxide precursor; and then treating in a reducing atmosphere to obtain the FeZnCuNiCo perovskite type high-entropy alloy catalyst which contains metal components of La, Cr, Ni, Mn, Fe, Zn, Cu and Co and takes a multi-metal alloy active center of Fe-Zn-Cu-Ni-Co as a main component. The high-entropy catalyst can meet the harsh requirements of high temperature, strong carbon deposition driving force and long-period operation in a propane dry reforming reaction, and is suitable for industrial application scenarios of continuous production of high-temperature synthesis gas.

The invention relates to the technical field of catalyst preparation, in particular to a preparation method of a modified catalyst and application of the modified catalyst in methanol regeneration in methane conversion, and the preparation method comprises the following steps: S1, mixing zinc nitrate, urea, a mesoporous regulating agent and deionized water, and stirring under a water bath condition; s2, aging the mixed solution obtained in the step S1 at 68-70 DEG C for 2-3 hours, centrifugally separating, washing the solid with deionized water until the solid is neutral, washing with absolute ethyl alcohol, and drying to obtain precursor powder; and S3, ball-milling and mixing the precursor powder, urea and the load modifier for 20-30 minutes, calcining in a muffle furnace in an air atmosphere, naturally cooling, grinding, and sieving with a 200-mesh sieve to obtain the nitrogen-doped modified catalyst. Aiming at the field of preparing high-value chemicals from methane through photocatalysis, the invention provides a method for inhibiting the peroxidation of methane by constructing chemical bonds to solve the problem of generating carbon dioxide by peroxidation of methane, and provides a new method for solving the problem of peroxidation of methane.

The application belongs to the technical field of fluorescent material synthesis, and particularly relates to a blue fluorescent powder with self-activation effect and a preparation method thereof, the chemical formula of the blue fluorescent powder is Li2Mg2W2O9 or Li2Zn2W2O9; the preparation comprises the following steps: 1) according to the chemical proportion of the fluorescent powder, magnesium / zinc source, lithium source and tungsten source are weighed and uniformly ground; 2) the uniformly ground mixed powder is placed into an alumina crucible, sintering is carried out, and the product is fully reacted after heat preservation for a period of time; 3) the product is uniformly ground again after cooling, and the blue fluorescent powder with self-activation effect is obtained. The application utilizes the special lattice structure of the substrate, and obtains the blue fluorescent powder with self-activation effect under an air atmosphere; the generated product has high purity, simple synthesis conditions, low cost and is easy to be prepared on a large scale; the prepared fluorescent powder has a high internal quantum efficiency of 68.7%, high luminous intensity and unique blue light emission characteristics.

The invention provides a processing method and application of seaweed mud-based biochar. The method comprises the following steps: (1) cleaning and deodorizing treatment: adding water into seaweed mud, stirring, precipitating and separating impurities, adding a sodium hydroxide solution, carrying out alkali washing and swelling, removing impurities and fishy smell, and forming a porous structure; (2) adding an iron salt solution for pretreatment to enable the seaweed mud to adsorb iron ions, filtering after adsorption is completed, and performing ball milling on a filtered product to obtain ball-milled seaweed mud particles; (3) pre-oxidizing in an air atmosphere, raising the temperature to 160-180 DEG C, and keeping the temperature for 2-5 hours; and (4) performing pyrolysis under the protection of nitrogen, heating to 900-1300 DEG C, and keeping the temperature for 8-16 hours to obtain the seaweed mud-based biochar. Through the steps of cleaning, alkali washing, ferric salt adsorption, pre-oxidation, pyrolysis and the like, impurities are effectively removed, the structure of the seaweed mud is improved, the mechanical property and conductivity of the seaweed mud are improved, and the seaweed mud can serve as an adsorption material or a fiber additive.

The invention belongs to the technical field of diaphragms, and particularly relates to a cellulose and cellulose derivative doped composite diaphragm as well as a preparation method and application thereof.The preparation method comprises the following steps: adding a thermoplastic organic high-molecular polymer, a cellulose derivative and metal oxide nanoparticles into an organic solvent, dissolving, adding a pore-foaming agent, and uniformly stirring; uniformly mixing, defoaming to obtain a membrane casting solution, and blade-coating to obtain a liquid membrane; the liquid film is placed in a wet air atmosphere with the relative humidity of 30%-80% for pre-phase inversion, in the pre-phase inversion process, water vapor in wet air permeates into the liquid film and exchanges with the organic solvent in the liquid film, and a wet film is obtained; and immersing the wet membrane into an extracting agent for phase conversion to obtain the cellulose and derivative doped composite diaphragm. According to the preparation method, safe operation of the diaphragm can be ensured, the electrolytic efficiency of the diaphragm is remarkably improved, and the diaphragm is excellent in stability of long-time operation.

The invention belongs to the technical field of air power supplies, and relates to modification treatment of an oxide, in particular to a cerium oxide doped transition metal oxide and a preparation method thereof, an air cathode and an air power supply. The preparation method comprises the following steps: dissolving cerium salt, cobalt salt and manganese salt in water, uniformly mixing to obtain a mixed solution, adjusting the pH value of the mixed solution to 9-11, and carrying out a sedimentation reaction to obtain a sediment; and drying the precipitate, and calcining in an air atmosphere at 300 + / -10 DEG C for 2-4 hours to obtain the cerium oxide doped transition metal oxide. The cerium oxide doped transition metal oxide is cerium doped cobalt manganese oxide with a spinel structure, and the doping amount of cerium is 20 + / -1wt%. The cerium oxide doped transition metal oxide provided by the invention is applied to an air cathode as a catalyst, and has good stability and high catalytic activity. The performance of an air power supply containing the oxide is remarkably improved. The method for preparing the oxide provided by the invention is simple and easy to operate, and is suitable for large-scale production.

The invention discloses a conjugated polymer photocatalyst, a preparation method thereof and application of the conjugated polymer photocatalyst in photocatalytic synthesis of nitric acid, and belongs to the technical field of polymer materials and photocatalysis. The preparation method of the catalyst mainly comprises the following steps: synthesizing an intermediate 2CzTPN-Br through a nucleophilic substitution reaction, then synthesizing an intermediate TBBA through an esterification reaction, and finally copolymerizing the intermediate 2CzTPN-Br and the intermediate TBBA through a coupling polymerization reaction to obtain the target catalyst. The preparation method disclosed by the invention is controllable in process, and the obtained catalyst does not need to participate in noble metal and has wide light absorption, high specific surface area and excellent carrier separation efficiency; when being applied to photocatalytic synthesis of nitric acid, nitrogen in air can be directly and efficiently converted into nitric acid under the mild conditions of room temperature, air atmosphere and water serving as a solvent, excellent durability is shown, the yield of nitric acid can reach 4466.2 mol g <-1 > cat after 324-hour continuous illumination, and wide application prospects are achieved in the field of green synthesis.

The invention discloses a zinc oxide modified silicon dioxide catalyst, a preparation method and application of the zinc oxide modified silicon dioxide catalyst in catalytic alcoholysis of waste PET (polyethylene terephthalate), zinc acetate and silicon dioxide are added into a mixed solution of water and ethanol and uniformly mixed, and a mixed reaction solution is obtained; adding a sodium hydroxide aqueous solution into the mixed reaction solution, carrying out a first reaction, and standing to obtain a suspension; and adding an L-ascorbic acid aqueous solution into the suspension, carrying out a second reaction, carrying out solid-liquid separation, and calcining the solid part in an air atmosphere to obtain the product. The prepared zinc oxide modified silicon dioxide nano material can be used as a catalyst to be applied to alcoholysis recovery of waste polyester, the product yield reaches up to 92% or above, the product selectivity is high, metal residues are avoided, the catalyst is easy to recover and can be recycled, and the application prospect is wide.

The invention discloses a preparation method of an iron-doped cerium-based perovskite type high-selectivity Cu ion capture stabilizing agent and application of the stabilizing agent in heavy metal pollution remediation, and the stabilizing agent is prepared through a sol-gel method and comprises the steps that cerous nitrate and citric acid are dissolved in water, and the mixture is heated and stirred to be gel-shaped; standing the gel solution in a drying oven at a constant temperature to obtain a Fe-Ce-PVSK precursor; grinding the precursor into powder, putting the powder into a quartz boat, and calcining in an air atmosphere through a horizontal tube furnace to obtain a product; and finally, washing to be neutral to obtain the iron-doped cerium-based perovskite stabilizing agent. Due to the high oxygen vacancy concentration and rich active sites, the stabilizing agent has high selectivity and high adsorption capacity and has specific capturing capacity on Cu < 2 + >. The preparation method has mild reaction conditions. The stabilizing agent can effectively reduce the bio-availability of heavy metals in a polluted matrix, promote healthy growth of plants, and realize pollution restoration and ecological function recovery at the same time.

The invention discloses a carbon-coated zinc oxide / carbon nitride heterojunction photocatalyst as well as a preparation method and application thereof. The carbon-coated zinc oxide / carbon nitride heterojunction photocatalyst is formed by crosslinking a carbon-coated zinc oxide nanosheet and a carbon nitride nanosheet through a carbon layer, and a heterojunction is formed between the carbon-coated zinc oxide nanosheet and the carbon nitride nanosheet. The preparation method comprises the following steps: mixing and grinding a carbon-coated zinc oxide nano-material and a carbon nitride nano-sheet, and calcining in a protective atmosphere. The carbon-coated zinc oxide / carbon nitride heterojunction photocatalyst can effectively promote photon-generated carrier separation, reduce the recombination rate of electron-hole pairs, and significantly improve the efficiency of photocatalytic production of hydrogen peroxide in an air atmosphere. Meanwhile, hydrogen peroxide generated in situ can react with bicarbonate in the system to generate peroxybicarbonate with high oxidation activity, and active oxygen species such as hydroxyl radicals are generated through activation in the photocatalytic process, so that the degradation capacity on the organic pollutants is further enhanced, and efficient degradation of the organic pollutants is realized.

The invention discloses modified egg shell powder with a high-activity porous structure and a preparation method of the modified egg shell powder. The material is prepared by the following steps: cleaning egg shells, calcining for 15-40 minutes in an air atmosphere of 300-400 DEG C, grinding and grading, and carrying out surface modification by a silane coupling agent containing amino groups and / or epoxy groups. The BET specific surface area of the modified egg shell powder is larger than 5 m / g, and the surface water contact angle is larger than 90 degrees. Comparison experiments prove that the eggshell powder treated by the method disclosed by the invention has obviously improved surface reaction activity, a porous structure and fundamentally improved interface bonding force with a polymer matrix. The material can be used as a functional filler in the field of composite materials.

The invention discloses a method for directly preparing high-purity Li2S by utilizing carbothermal reduction, which comprises the following steps: ball-milling and mixing Li2SO4.H2O and a carbon source, and carrying out first-step calcination in an air atmosphere at the calcination temperature of 450-550 DEG C to obtain a first-step calcination product; carrying out ball-milling mixing on the first-step calcined product and sublimed sulfur powder, tabletting, and carrying out second-step calcination at the calcination temperature of 700-800 DEG C under the protection of inert gas to obtain a second-step calcined product; and continuously performing third-step calcination on the second-step calcination product under the protection of inert gas at the calcination temperature of 850-950 DEG C to obtain the product Li2S. Lithium sulfate and a high-purity carbon source are adopted as main raw materials, sublimed sulfur powder is introduced in the second-step calcination process to inhibit generation of Li2O, after the carbon source is consumed in the second-step calcination process, a mixture of lithium sulfide and residual lithium sulfate is obtained, the temperature continues to rise, third-step calcination is conducted, the residual lithium sulfate is molten, volatilized and removed, and the lithium sulfide is obtained. And discharging the mixture out of the tubular furnace along with the gas flow of the inert gas to obtain high-purity lithium sulfide.

The invention discloses a nitrogen plasma vapor deposition modified metal oxide catalyst and a preparation method and application thereof.The preparation method of the catalyst comprises the steps that tin salt, CTAB and ammonia water serve as raw materials, SnO2 is prepared through a solution gel method, then the preliminarily-prepared SnO2 is calcined in the air atmosphere, purer SnO2 is prepared, and the catalyst is used for preparing the metal oxide catalyst. And finally, carrying out chemical vapor deposition modification on SnO2 by utilizing high-energy-state N * plasma to prepare the catalyst. The nitrogen-doped tin dioxide catalyst is synthesized on the basis of a chemical vapor deposition method strategy, and the catalyst shows extraordinary performance of electrocatalytic oxygen reduction for synthesis of hydrogen peroxide in an alkaline medium, has good stability and a wide potential window, and has potential application prospects in the field of electrochemical preparation of hydrogen peroxide.

The invention relates to a ceramic aerogel with a multi-scale heterostructure and a preparation method thereof, and the preparation method comprises the following steps: dipping carbon fibers in a reduced graphene oxide aqueous solution, and drying to obtain a Cf / RGO composite material; the preparation method comprises the following steps: by taking methyltriethoxysilane and dimethyldimethoxysilane as silicon sources, deionized water as a hydrolytic agent and tetramethylammonium hydroxide as a catalyst, mixing to obtain siloxane gel, and drying to obtain siloxane dry aerogel; and placing the Cf / RGO stacked layer by layer on the siloxane dry aerogel, carrying out high-temperature gas phase siliconizing to obtain a SiC / C composite fiber material, and carrying out air atmosphere heat treatment to obtain the layered hollow fiber skeleton based SiC-coated SiO2 nanowire aerogel. The aerogel disclosed by the invention has the characteristics of light weight, high temperature resistance, strong mechanical property and the like, collaborative optimization of mechanical-thermal-electromagnetic properties is realized, and a new thought is provided for cross-scale design of stealth materials under a high-temperature multi-physical field coupling condition.

The application belongs to the technical field of sensitive materials, and discloses a high-performance TiO2@In2O3 / Pd sensitive film for a MEMS gas sensor, a synthesis method thereof and a MEMS gas sensor. The method comprises the following steps: synthesizing mesoporous TiO2 nanoparticle balls; mixing indium salt, an alkaline compound, a surfactant and the mesoporous TiO2 nanoparticle balls uniformly, and then performing hydrothermal reaction; centrifuging, washing and drying the product of the hydrothermal reaction, and then performing first annealing treatment in an air atmosphere to obtain In2O3-coated titanium dioxide nanoparticle balls TiO2@In2O3; modifying palladium nanoparticles to the nanoparticle balls TiO2@In2O3 by a solution method, centrifuging, washing and drying, and then performing second annealing treatment in a hydrogen atmosphere to obtain In2O3-coated titanium dioxide nanoparticle balls TiO2@In2O3 / Pd with Pd modification; and manufacturing the nanoparticle balls TiO2@In2O3 / Pd into a sensitive film. The sensitive film manufactured by the above method can improve the sensitivity of gas detection.

The invention provides a modified hard carbon material and a preparation method thereof, a negative pole piece and a sodium ion battery, and belongs to the technical field of sodium ion batteries. The preparation method comprises the following steps: S1, waste cotton cloth is pretreated, the pretreatment comprises crushing treatment, polishing treatment, washing treatment and drying treatment, and pretreated waste cotton cloth is obtained; s2, the pretreated waste cotton cloth is subjected to pre-oxidation treatment in the air atmosphere, and pre-oxidized waste cotton cloth is obtained; s3, carrying out carbonization treatment on the pre-oxidized waste cotton cloth in an inert atmosphere to obtain a hard carbon material; and S4, mixing the hard carbon material with sulfur powder, and performing vulcanization treatment in an inert atmosphere to obtain the modified hard carbon material. The modified hard carbon material prepared by the preparation method has excellent sodium storage performance.

The application discloses a preparation method and application of blue-green algae-based biochar with Fenton-like oxidation function. The preparation method comprises the following steps: (1) selecting an iron-containing flocculant, adding the iron-containing flocculant into natural lake water containing blue-green algae, and then performing sufficient stirring, standing, filtration, drying, crushing and sieving to obtain blue-green algae powder; (2) placing the blue-green algae powder in a tubular furnace for pyrolysis treatment to obtain preformed carbon; then, immersing the preformed carbon in an activating agent solution, performing sufficient immersion, drying, placing the preformed carbon in the tubular furnace for activation treatment, and finally performing heat treatment under air atmosphere to obtain blue-green algae-based biochar material with Fenton-like oxidation function. The application provides application of the prepared blue-green algae-based biochar in dye wastewater treatment, and the dye wastewater treatment is performed in the presence of hydrogen peroxide, and the blue-green algae-based biochar has high degradation removal rate and high stability.

The present invention provides a preparation method and application of Ru-RuO2 nanosheets, belonging to the technical field of nanomaterial preparation. The present invention first adds L-proline, ruthenium trichloride trihydrate, and urea to ethanol, ultrasonically dissolves them, and then heats them to form a colloidal liquid, and then performs Joule heat treatment under an air atmosphere to obtain Ru-RuO2 nanosheets. This method does not require surfactants, templates, reducing atmospheres, and complex calcination processes, and can achieve the preparation of porous heterojunction Ru-RuO2 nanosheets with high efficiency and low energy consumption, and has prospects for industrial application. This two-dimensional porous heterojunction formed by in-situ calcination has a rich interface structure, can give full play to the synergistic effect of the two components, and significantly improves its activity and stability in acidic water electrolysis applications.

The invention discloses preparation of a nickel and cerium doped cobalt-based catalyst and application of the nickel and cerium doped cobalt-based catalyst in catalytic decomposition of nitrous oxide. The nickel and cerium doped cobalt-based catalyst is of a Ni and Ce co-doped spinel type Co3O4 structure and has a mesoporous structure, and the molar ratio of cobalt to nickel to cerium is 1: 0.12: 0.04. The preparation method comprises the following steps: preparing a mixed solution in which the molar ratio of cobalt nitrate to nickel nitrate to cerium nitrate is 1: 0.12: 0.04 by adopting a coprecipitation method, adding sodium carbonate as a coprecipitator into the mixed solution, adjusting the pH value of the mixed solution to 9 while stirring, carrying out coprecipitation and aging, then washing and drying the precipitate, and roasting for 3 hours in an air atmosphere at 300-400 DEG C to obtain the nickel and cerium doped cobalt-based catalyst. The catalyst provided by the invention has good low-temperature nitrous oxide decomposition capability and anti-interference capability under complex working conditions.

This invention discloses manganese ion-substituted MgCoNiCuZn high-entropy oxides, their preparation methods, and applications, belonging to the field of metallic materials technology. It is a Mg... （1‑x） / 4 Co （1‑x） / 4 Ni x Cu （1‑x） / 4Zn （1‑x） / 4‑z Mn z O high-entropy oxides or Mg （1‑y） / 4 Co （1‑y） / 4Ni y Cu （1‑y） / 4 Zn （1‑y） / 4‑z Mn z The high-entropy oxides, with x and y values ​​of 0.15–0.35 and z values ​​of 0.02–0.08, are prepared by ball milling MgO, CoO, NiO, CuO, ZnO, and MnO powders in stoichiometric ratio, vacuum drying, thorough grinding, and then spreading the mixture evenly. The mixture is then placed in batches in a high-temperature tube furnace, slowly heated in an air atmosphere, held at that temperature, and then slowly cooled with the furnace. By gradually replacing Zn with Mn, the resulting high-entropy oxides exhibit excellent electrochemical performance.

The invention discloses a hierarchical pore UiO-66 supported crown ether composite material, a preparation method thereof and application of the hierarchical pore UiO-66 supported crown ether composite material in adsorption and extraction of 6Li < + > from complex systems such as salt lake brine. The preparation method comprises the following steps: preparing terephthalic acid, 2-aminoterephthalic acid and a zirconium source through a solvothermal method to obtain a mixed ligand UiO-66, and then pyrolyzing the mixed ligand UiO-66 in an air atmosphere to obtain the hierarchical pore UiO-66; the hierarchical pore UiO-66 and a crown ether solution are mixed and stirred to react for a period of time, then solid-liquid separation is carried out, solids are collected, and the hierarchical pore UiO-66 loaded crown ether composite material is obtained after cleaning and drying. The hierarchical pore UiO-66 loaded crown ether composite material has the advantages of high specific surface area, high dispersion of crown ether adsorption sites, high crown ether loading capacity, high selectivity of 6Li < + > metal ions and the like, and can realize one-step enrichment of 6Li < + > metal ions in complex systems such as salt lake brine.

The invention relates to spherical high-entropy carbide powder and a preparation method of a SiC / high-entropy carbide coating. According to the method, normal-pressure carbon thermal reduction synthesis of high-entropy carbides is realized in a common box-type furnace and in an air atmosphere through a local atmosphere isolation structure of'laying graphite paper, upper graphite powder and covering activated carbon ', then a compact SiC transition layer is generated in situ on a substrate by utilizing a two-step method of'plasma spraying of a pure silicon layer and then high-temperature embedding carburization', and the high-entropy carbide is prepared. And finally, the high-entropy carbide coating is prepared through a thermal spraying method. The process is simple, the cost is low, large-scale preparation is easy, the high-temperature wear resistance and the ablation resistance of the coating can be remarkably improved, and the harsh requirements of the aerospace field and the like for the ultra-high-temperature protective coating are met.

The invention discloses a method for preparing high-density yttrium oxyfluoride ceramic by combining a hydrothermal method and hot pressed sintering. The method comprises the following steps: (1) respectively preparing a yttrium nitrate (Y (NO3) 3.6 H2O) solution and an ammonium fluoride (NH4F) solution; (2) mixing the raw materials, and stirring for 10 to 20 minutes; (3) adding a sodium hydroxide solution into the mixed solution to adjust the pH value of the system to 10-12, and continuously stirring for 10-20 minutes to obtain a premixed solution; (4) transferring the premixed solution into a hydrothermal kettle, and carrying out hydrothermal reaction under a high-temperature condition; (5) carrying out centrifugal separation and drying treatment on the hydrothermal reaction product to obtain a yttrium oxyfluoride precursor; (6) calcining the precursor in a muffle furnace in an air atmosphere; and (7) carrying out hot pressed sintering on the obtained powder under the conditions of 750-1000 DEG C and 20-40 MPa, and carrying out heat preservation for 30-90 minutes. The obtained ceramic has high compactness and excellent plasma etching resistance.