364 results about "Chromium oxide" patented technology

The invention relates to a modified chrome corundum ramming material and a preparation and construction process thereof, and belongs to the technical field of chrome corundum ramming materials. The ramming material comprises a material A, a material B and a material C, wherein the material A comprises chrome corundum aggregate, titanium dioxide coated aluminum oxide microspheres, calcium sulfide dehydrate and silicon carbide porous microspheres; the material B comprises chromium oxide-zirconium oxide composite nano powder, sodium thiosulfate pentahydrate, tricalcium phosphate and hexagonal boron nitride flaky crystals; and the material C comprises an aluminum dihydrogen phosphate-magnesium hydroxide compound, a calcium fluoride-aluminum oxide co-melt and a silane coupling agent. The preparation process comprises the steps of pretreatment of all the components, preparation of composite powder and layered preparation. The construction process comprises the steps of pretreatment, wet-process mixing, layered ramming, negative-pressure permeation, medium-temperature reaction, spraying curing, integral firing and the like. Generation of hexavalent chromium can be effectively inhibited, the thermal shock resistance, the mechanical strength and the heat-conducting property of the material are remarkably improved, and the material has the advantages of being good in environment friendliness, long in service life, excellent in construction performance and the like.

The invention relates to the field of refractory materials, in particular to a dry ramming mass for an intermediate frequency furnace and a preparation method thereof.The dry ramming mass is prepared from, by weight, 45-55 parts of fused corundum, 8-12 parts of fused magnesia, 15-20 parts of tabular corundum, 3-5 parts of fused spinel, 3-4 parts of activated aluminum oxide, 1-2 parts of silicon carbide, 1-2 parts of silica sol and 0.5-1 part of boric acid. 3.5-4.5 parts of a binding agent and 3-5 parts of an anti-penetrating agent; wherein the anti-penetrating agent is chromium oxide coated nickel aluminate microspheres. The invention solves the two major problems of easy penetration and thermal shock peeling of the traditional furnace lining, is especially suitable for harsh smelting environments of high manganese steel, stainless steel and the like, and has long service life and convenience in construction.

The invention relates to the technical field of alloy processing, and discloses a high-performance corrosion-resistant nickel-based alloy plate and a preparation method thereof, and the method comprises the following steps: raw material preparation, smelting treatment, casting treatment, hot rolling treatment, solution treatment, aging treatment and surface passivation treatment. According to the invention, when a composite acid system is adopted for passivation treatment, the concentration of chromium / molybdenum atoms in a passivation film is optimized and balanced due to the specific ratio of nitric acid to chromic acid, a chromium oxide provides a compact passivation barrier, and a molybdenum oxide endows the film layer with a self-repairing characteristic to synergistically inhibit pitting nucleation; meanwhile, nano titanium dioxide particles pretreated by silane are embedded into the passivation film in situ under the action of ultrasonic oscillation, organic pollutants adsorbed on a film layer can be decomposed by the photocatalytic characteristic of the nano titanium dioxide particles, the local corrosion effect of a battery caused by dirt coverage is avoided, and the performance of the battery is improved through double upgrading of components and the structure of the passivation film. And the alloy plate has excellent pitting corrosion resistance and fouling resistance in a chloride ion-containing medium.

Provided is a surface-treated steel sheet that can be produced without the use of hexavalent chromium and that combines excellent film corrosion resistance, coating corrosion resistance, film wet adhesion, coating secondary adhesion, and weldability. At least one side of the surface-treated steel sheet includes a Ni-containing layer, a metallic Cr layer on the Ni-containing layer, and an oxidized Cr layer on the metallic Cr layer. The water contact angle is 50° or less, and the total atomic ratio to Cr of K, Na, Mg, and Ca adsorbed on the surface is 5.0% or less.

The application discloses a kind of high-performance coiled material powder coating and preparation method thereof, belong to powder coating technical field, the application is by the compounding of organosilicon modified epoxy resin and carboxyl-terminated polyester resin, after organosilicon modification, the segment of introduction-Si-O-Si in system has high flexibility, and synergistic effect with nano calcium carbonate, it is helpful to balance the adhesion and flexibility of coating, grafting modification graphene oxide, active chromium oxide is added again, can obviously improve the mechanical strength of coating;After then, phosphite group is grafted onto graphene oxide, and is applied in the present powder coating system, can form three-dimensional network structure in system, chemical bond effect, not only can improve its crosslinking stability in system, and the sheet structure of graphene oxide, also can play certain barrier property, can also give coating longer weather resistance, and active chromium oxide synergistic effect is further improved, and the weather resistance and corrosion resistance of coating.

The invention belongs to the technical field of EBSD sample preparation of heterogeneous materials, and particularly relates to an EBSD sample preparation method of an Al7075 / Al6061 bimetal composite cast ingot. According to the method, mechanical grinding and polishing and argon ion polishing are combined for EBSD sample preparation, during mechanical grinding and polishing, aluminum oxide polishing paste is selected for rough polishing, aluminum oxide or chromium oxide polishing paste is selected for fine polishing, and finally cerium oxide polishing paste is selected for fine polishing, so that crystal lattices with complete and distortionless sample surface layers are obtained as far as possible, and the defects such as trailing are reduced to the maximum extent; the optimal surface characteristics are provided for subsequent argon ion polishing, and meanwhile, the calibration rate of an Al7075 / Al6061 bimetal composite cast ingot EBSD sample prepared through the method is not lower than 90% in combination with the optimal argon ion polishing process parameters.

The invention discloses a high-performance coiled material powder coating and a preparation method thereof, and belongs to the technical field of powder paints.The high-performance coiled material powder coating has the advantages that organosilicon modified epoxy resin and carboxyl-terminated polyester resin are compounded, a-Si-O-Si-chain segment is introduced into a system after organosilicon modification, the flexibility is high, and the high-performance coiled material powder coating has a synergistic effect with nano calcium carbonate; the adhesive force and the flexibility of the coating are balanced, and the mechanical strength of the coating can be obviously improved by adding the grafted modified graphene oxide and the active chromic oxide; then, phosphite ester groups are grafted to the graphene oxide, the graphene oxide is applied to a powder coating system, a three-dimensional network structure and chemical bonding can be formed in the system, the crosslinking stability of the graphene oxide in the system can be improved, and a certain barrier property can be achieved due to the flaky structure of the graphene oxide; and the coating is endowed with long-acting weather resistance, and the weather resistance and the corrosion resistance of the coating are further improved through the synergistic effect with the active chromic oxide.

The invention relates to the field of vanadium and chromium separation, and particularly discloses a sodium vanadium solution treatment method which comprises the following steps: S100, adding an alkaline reducing agent into a sodium vanadium solution, and carrying out reduction of hexavalent chromium and selective precipitation reaction of trivalent chromium; s200, at the later stage of the reaction in the step S100, urea is added into a solution system, and a deep removal reaction of silicon and chromium is carried out; and S300, after the reaction in the step S200 is finished, solid-liquid separation is conducted, silicon-chromium slag and purified vanadium liquid are obtained, silicon-chromium oxide is obtained after the silicon-chromium slag is treated and can be used for smelting silicon-chromium alloy, and the purified vanadium liquid is subsequently used for preparing a high-purity vanadium oxide product. According to the method, the vanadium sodium salt solution obtained through a vanadium slag sodium salt roasting-water leaching process is used as a raw material, hexavalent chromium in the solution is reduced through an alkaline reducing agent, selective precipitation separation of hexavalent chromium and vanadium is achieved, and meanwhile urea is supplemented to conduct synergistic precipitation removal on silicon in the solution.

The invention discloses a preparation method and application of a sodium-ion battery positive electrode material, and relates to the technical field of sodium-ion batteries, and the preparation method comprises the following steps: (1) dissolving a compound containing a Cr element in water, adding the solution into a reaction kettle, gradually dropwise adding a NaOH solution, after the reaction is completed, gradually adding a chitosan hydrochloride aqueous solution into the reaction kettle according to a certain ratio, and stirring to obtain a mixed solution; after reacting for a certain time, filtering, washing and drying to obtain chitosan-coated chromium hydroxide Cr (OH) 3 (at) CS; (2) blending the Cr (OH) 3 (at) CS prepared in the step (1) with a sodium source according to a certain molar ratio, sintering the mixture under protective gas, and then grinding and sieving to obtain a carbon-coated sodium chromite positive electrode material NaCrO2 (at) C; the sodium-ion battery has good electrochemical performance and cycle performance, and the sustainable development of the sodium-ion battery industry is promoted.

The invention provides self-recovery chromium ion doped oxide mechanoluminescence fluorescent powder as well as a preparation method and application thereof. The chemical general formula of the self-recovery mechanoluminescence fluorescent powder is Al2 (1-x) O3: 2xCr < 3 + >, wherein x is equal to 0.3%-5%. The preparation method of the self-recovery mechanoluminescence fluorescent powder comprises the following steps: a, respectively weighing aluminum oxide and chromium oxide according to the molar ratio of each element in the chemical general formula Al2 (1-x) O3: 2xCr < 3 + >; b, grinding and uniformly mixing the weighed raw materials, and firing in air at the temperature of 1300 DEG C for 6 hours; and c, taking out the fired sample, and uniformly grinding to obtain the chromium ion doped oxide mechanoluminescence fluorescent powder. According to the chromium ion doped oxide mechanoluminescence fluorescent powder disclosed by the invention, a measured emission band main peak is located at 694 nm and is located at a biological first window (600-900 nm), and the chromium ion doped oxide mechanoluminescence fluorescent powder is expected to be used as a near-infrared mechanoluminescence biological probe; and the fluorescent powder has the advantages of no need of pre-irradiation and instant self-recovery of luminescence.

The application provides a temperature self-compensation strain sensor sensitive layer composite material and a preparation method thereof, and belongs to the technical field of functional materials. The composite material is prepared from raw materials including the following mass percentages: metal nanoparticles 25-35%, insulating oxide nanoparticles 2-3%, dispersing agent 0.1-0.5%, and the balance solvent; the metal nanoparticles have a positive temperature coefficient of resistance; and the insulating oxide nanoparticles include aluminum oxide nanoparticles, silicon oxide nanoparticles, zirconium oxide nanoparticles or chromium oxide nanoparticles. The composite material provided by the application can be used as a sensitive layer of a temperature self-compensation strain sensor, can avoid strain signal disturbance caused by environmental temperature changes, can make the strain sensor have a temperature self-compensation function, and can further simplify the system of the strain sensor without using an external circuit and without changing the size and structure of the strain sensor.

The invention discloses a halogen anion doped chromic oxide electrocatalyst and a preparation method and application thereof, and belongs to the technical field of new energy materials and electrochemical catalyst.The preparation method of the electrocatalyst comprises the steps that soluble chromium salt and polyvinylpyrrolidone are dissolved in a mannitol solution and then mixed with a soluble halogen salt solution, stirring is conducted, and the electrocatalyst is obtained; preparing to obtain a mixed solution; in a closed environment, heating the mixed solution at 160-180 DEG C for 6-24 hours to perform hydrothermal reaction, obtaining a reaction product after the reaction is finished, and then calcining in an air atmosphere to prepare the powdery halogen anion doped chromic oxide electrocatalyst, according to the method, the local structure, the spinning state, the energy band and the like of chromic oxide are regulated and controlled through the doped halogen anion ligand, the OER catalytic activity of the chromic oxide is optimized, the process is simple, and the method has good application prospects in the water electrolysis technology.

The invention relates to the technical field of thermal-shock-resistant refractory materials, and discloses a thermal-shock-resistant refractory material for a melting furnace and a preparation method of the thermal-shock-resistant refractory material. Comprising the following operation steps: step 1, uniformly mixing fused cast fused alumina zirconia, white corundum, aluminum oxide, chromic oxide and modified iron oxide, adding a modified polycarbosilane binder, heating to 250-300 DEG C, and mixing for 20-40 minutes to obtain a mixed material; 2, the mixed material is subjected to hot pressing treatment for 3-4 hours, and a blank is prepared; and sintering at 1600-2000 DEG C for 20-30 hours to obtain the thermal shock resistant refractory material.

Magnetic particles with a highly reflective protective membrane (300), comprising: a magnetic core (100), a shell (200) formed on the outer surface of the magnetic core (100), having a multi-layer structure and comprising a first shell (210) made of a dielectric material, and a second shell (220) made of metallic material, formed on the outer surface of the first shell (210) and being a multi-layer membrane in which two or more layers (221, 222, 223) of mutually different metallic materials are stacked on top of each other, and a highly reflective protective membrane (300) which is in contact with the second shell (220) and is formed on the outer surface of the shell (200), wherein the highly reflective protective membrane (300) comprises a multi-layer structure comprising a low refractive index membrane (310) formed on the outer surface of the shell (200) and having an optical thickness between 0.15 to 0.35 of the wavelength, and a high refractive index membrane (320) formed on the outer surface of the low refractive index membrane (310) and having an optical thickness between 0.15 to 0.35 of the wavelength, the dielectric material is one or more materials selected from a group comprising titanium dioxide, aluminum oxide, calcium carbonate, zirconium oxide, magnesium fluoride, zinc oxide and zinc sulfide, the metallic material is one or more materials selected from a group comprising copper, nickel, gold, platinum, silver, aluminum and chromium, the low refractive index membrane (310) consists of one or more materials selected from a group comprising silicon dioxide, magnesium fluoride, polystyrene, polymethyl methacrylate, polystyrene-co-butadiene, vanadium pentoxide, cadmium oxide, polyisobutylene and polyethylene, and the high refractive index membrane (320) consists of one or more materials selected from a group comprising titanium dioxide, aluminum oxide, zinc oxide, zirconium oxide and chromium oxide.

The invention relates to the field of vanadium and chromium separation, and particularly discloses a method for removing impurities phosphorus, chromium and silicon in a sodium modified vanadium solution, which comprises the following steps: S100, adjusting the pH value of the sodium modified vanadium solution to enable the pH value of a solution system to be 8.0-9.0 at room temperature to obtain a pretreated sodium modified vanadium solution; s200, heating the pretreated sodium vanadium solution, sequentially adding a reducing agent and a polyelectrolyte into the solution while stirring, and carrying out phosphorus and chromium removal reaction while stirring; s300, after the removal reaction of phosphorus and chromium is carried out for a period of time, adding a silicon removal agent, and carrying out a removal reaction of silicon; and S400, after the silicon removal reaction is finished, standing sedimentation and solid-liquid separation are carried out, impurity-removed slag is washed with water and then merged into the filtrate, and purified vanadium liquid is obtained. According to the method, firstly, glucose is adopted to selectively reduce hexavalent chromium into trivalent chromium under the weakly alkaline condition, pentavalent vanadium is not reduced, the trivalent chromium forms chromium phosphate and chromium hydroxide precipitates in a weakly alkaline solution, and meanwhile, the chromium removal efficiency is improved in a polyelectrolyte coagulation mode.

The application discloses a preparation method of vanadium-doped and high-hydrated mangan-chromian spinel monocrystal under high temperature and high pressure. The cylindrical mangan-chromian spinel sample is prepared by taking solid rose triangular rhombic manganese carbonate crystal, solid chromium (III) acetate hydroxide crystalline powder, solid vanadium (IV) acetylacetonate oxide powder, solid oxalic acid powder, solid bixbyite powder, solid chromium hydroxide powder and liquid dilute nitric acid as starting raw materials; two pieces of water source sheets are made from the bixbyite powder and the chromium hydroxide powder with a weight ratio of 4:1; the two pieces of water source sheets are placed at two ends of the cylindrical mangan-chromian spinel sample and then are placed into a double-capsule structure experimental sample bin with an inner layer sleeve being a graphite tube and an outer layer sleeve being a gold-palladium alloy tube; the high temperature and high pressure reaction is carried out to obtain the mangan-chromian spinel monocrystal; and the preparation technology blank of the vanadium-doped and high-hydrated mangan-chromian spinel large-particle monocrystal under the current high temperature and high pressure conditions is solved.

A preparation method of a 7B04 aluminum alloy surface in-situ synthesis microparticle enhanced thermal control function film layer can effectively improve the density of the film layer, meanwhile, the film layer is high in infrared emissivity and good in thermal control function, and comprises the steps that firstly, the 7B04 aluminum alloy surface, copper oxide and chromic oxide are pretreated, then a micro-arc oxidation electrolyte is prepared, and the 7B04 aluminum alloy surface is subjected to in-situ synthesis; the pretreated 7B04 aluminum alloy is placed in a stainless steel electrolytic cell of micro-arc oxidation equipment, then the micro-arc oxidation electrolyte is added into the stainless steel electrolytic cell, micro-arc oxidation treatment is conducted on the aluminum alloy through a micro-arc oxidation power source, the electrolyte is continuously stirred in the oxidation treatment process, and the aluminum alloy is subjected to micro-arc oxidation treatment; and finally, obtaining an in-situ synthesized microparticle reinforced thermal control functional film layer on the surface of the 7B04 aluminum alloy, washing the film layer with deionized water, and naturally airing the film layer to obtain the 7B04 aluminum alloy. The composition of the micro-arc oxidation electrolyte is designed, in the growth process of a micro-arc oxidation film layer, copper chromite black particles are synthesized in situ through chemical reaction, the particles and the film layer are metallurgically bonded, and the method has actual application and popularization value.

The invention discloses a method for preparing brown aluminum oxide by smelting chromium-aluminum spinel. The method comprises the following steps: crushing the chromium-aluminum spinel into chromium-aluminum spinel particles; the chromium-aluminum spinel particles and the carbon particles are mixed, and a mixture is obtained; putting the mixture into an electric arc furnace for bottoming and compacting; electrifying and smelting by using a three-phase graphite electrode; after smelting is completed, cooling water is continuously introduced into the electric arc furnace for cooling for a period of time, and then natural cooling is conducted; and disassembling the furnace, cleaning and separating brown aluminum oxide and high-carbon chromium metal, and packaging. According to the method, chromium trioxide in the chromium aluminate spinel is reduced into high-carbon metal chromium by adopting a carbon reduction smelting method, so that most of chromium trioxide is removed, a generated aluminum-containing product meets the impurity-containing requirement of brown aluminum oxide, and the high-carbon metal chromium is conveniently separated from the brown aluminum oxide by utilizing the characteristic that the density of the generated high-carbon metal chromium is greater than that of the brown aluminum oxide; the technological process is greatly simplified, and the production cost is saved.

The invention discloses a chromium-site high-entropy chromium lithium titanate material as well as a preparation method and application thereof, and belongs to the technical field of electrochemical energy storage materials. The crystal structure of the chromium-site high-entropy chromium lithium titanate material is a single spinel solid solution phase, and the chemical general formula of the chromium-site high-entropy chromium lithium titanate material is Li (Cr < 1-x-y-z-w > V < x > Fe < y > Mn < z > Al < w >) TiO4. According to the preparation method, chromium trioxide serves as an oxidizing agent, carbohydrate serves as a reducing agent, and rapid synthesis is achieved through a one-step combustion method. The process is simple and efficient, and the prepared chromium-site high-entropy chromium lithium titanate material has relatively high specific capacity and excellent cycling stability and can be applied as a lithium ion battery negative electrode material. According to the invention, the problems of limited theoretical capacity and poor rate capability of the existing chromium lithium titanate material are effectively solved, and a new way is provided for developing a high-performance lithium ion battery negative electrode material.

The application discloses a preparation method of a nickel-doped and high-hydrated cobalt-chromium-iron ore monocrystal under high temperature and high pressure, and the method comprises the following steps: preparing a cylindrical cobalt-chromium-iron ore sample by taking solid basic cobalt carbonate powder, solid chromium (III) acetate hydroxide crystal powder, solid nickel stearate, solid oxalic acid powder, solid chromium hydroxide powder, solid nickel hydroxide powder and liquid dilute nitric acid as starting raw materials; preparing water source sheets by taking chromium hydroxide powder and nickel hydroxide powder in a weight ratio of 4:1; placing two water source sheets at two ends of the cylindrical cobalt-chromium-iron ore sample respectively and then putting them into a double-capsule structure sample bin; and obtaining a cobalt-chromium-iron ore monocrystal after high-temperature and high-pressure reaction, so that the blank of the preparation technology of the nickel-doped and high-hydrated cobalt-chromium-iron ore large-grain monocrystal under the current high-temperature and high-pressure condition is solved, and the experimental sample of the nickel-doped and high-hydrated cobalt-chromium-iron ore large-grain monocrystal is obtained.

The application relates to a modified chrome-corundum ramming mixture and a preparation and construction process, and belongs to the technical field of chrome-corundum ramming mixtures. The ramming mixture comprises A material, B material and C material, the A material comprises chrome-corundum aggregates, titanium dioxide-coated alumina microspheres, calcium sulfide dihydrate and porous silicon carbide microspheres; the B material comprises chromium oxide-zirconium oxide composite nano powder, sodium thiosulfate pentahydrate, tricalcium phosphate and hexagonal boron nitride flaky crystals; and the C material comprises an aluminum dihydrogen phosphate-magnesium hydroxide compound, a calcium fluoride-alumina eutectic body and a silane coupling agent. The preparation process comprises pretreatment of components, preparation of composite powder and layered preparation; and the construction process comprises the steps of pretreatment, wet mixing, layered ramming, negative pressure infiltration, medium-temperature reaction, spraying and curing and overall sintering. The application can effectively inhibit the generation of hexavalent chromium, significantly improve the thermal shock resistance, mechanical strength and heat conduction performance of the material, and has the advantages of good environmental protection, long service life, excellent construction performance and the like.

This invention discloses a method for producing metallic chromium through carbon reduction vacuum melting, belonging to the field of metallic chromium preparation technology. The method includes: mixing chromium oxide green, additives, and binders, pressing the mixture into a block with internal permeable channels, drying it, and then placing it in a vacuum environment (≤5Pa) for single-stage high-temperature melting. The temperature is controlled within the range of 1350℃~1700℃, keeping the material in a semi-molten state to achieve complete reduction of chromium oxide green by carbon. High-purity, high-density metallic chromium is obtained in a single process. This invention employs a three-dimensional mixing + shear dispersion mode to process the material, improving mixing efficiency and uniformity, and facilitating the reaction. This invention creatively utilizes a vacuum semi-molten reduction mechanism, breaking the chemical equilibrium limitations of traditional solid-state carbon reduction and avoiding the complex process of multi-stage sintering. It has the advantages of thorough reaction, a short process, low energy consumption, low product impurities, and suitability for industrial production.

The invention discloses a resourceful treatment method for stainless steel pickling waste liquid and waste water. The waste liquid is divided into high-concentration waste liquid and low-concentration waste liquid according to the acid concentration and the salt concentration to be treated respectively. Sequentially recovering gypsum, chromic hydroxide, nickel sulfide, ferrous hydroxide and manganese-rich slag from the low-concentration waste liquid through gradient precipitation; and neutralizing free acid from the high-concentration waste liquid by using ferrous hydroxide generated in a low-concentration section, cooling and crystallizing to recover ferrous sulfate, deeply removing nickel by using nickel sulfide generated in the low-concentration section, and precipitating to recover chromium hydroxide. In the whole process, generation of ferric iron is strictly controlled, and high-value productization recovery of free acid and all metals is achieved. The method has the advantages of low medicament consumption, high metal recovery rate, high product value, no secondary pollution and the like.

The invention relates to the technical field of glass ceramics, in particular to a silicon dioxide-containing glass ceramic wafer substrate and a preparation method thereof. The preparation method comprises the following steps: weighing aluminum oxide, hydroxyethyl urea, chromium dioxide, lithium oxide, magnesium oxide, titanium dioxide, a clarifying agent, a toughening agent and silicon dioxide; preparing an aqueous solution from hydroxyethyl urea, and putting the powder, a clarifying agent, a toughening agent and the aqueous solution into a ball milling tank to obtain slurry; carrying out vacuum defoaming, tape casting, drying, glue removal heat treatment, glass melting, rolling and annealing treatment to obtain a glass plate; and polishing, ultrasonically cleaning and drying the glass plate to obtain the wafer substrate. According to the preparation method, hydroxyethyl urea and chromium dioxide are combined under a specific controlled heat treatment system, so that the functions of a conventional dispersing agent are exceeded, a unique toughening phase existing in a grain boundary is generated through in-situ reaction, uniform formation of a superfine nanocrystalline structure is realized synergistically, and thus the fracture toughness and the surface flatness of the material are synchronously and remarkably improved.

This invention provides a high-entropy alloy nano-coating high-temperature oxidation-resistant modification preparation process, belonging to the field of coating modification technology. The high-entropy alloy nano-coating high-temperature oxidation-resistant modification preparation process specifically includes the following steps: S1. Target material selection and preparation; S2. Alloy substrate treatment; S3. Low-temperature nanocrystalline coating deposition; S4. Coating densification treatment; S5. Low-temperature recovery annealing; S6. Pre-oxidation treatment. Through the synergistic process of low-temperature preparation of the alloy nano-coating, densification annealing, and pre-oxidation, the high-temperature strength and phase stability of the coating are improved by utilizing the lattice distortion effect. A thermodynamically stable protective oxide film of aluminum oxide and chromium oxide is generated in situ on the surface, solving the problems of traditional chromium-based coatings such as few main components, poor oxidation resistance, and short lifespan. This significantly improves the service reliability and safety of nuclear reactor structural materials under high-temperature irradiation environments.

A core-shell structure chromium oxide positive electrode and its preparation method, belonging to the technical field of lithium ion batteries. The material is: the chemical formula of the core-shell structure chromium oxide positive electrode is M x Cr 8‑x O 21 ‑@LLZAO, including doped M x Cr 8‑x O 21 The core is a garnet electrolyte and the LLZAO coating is a shell, wherein M is one or more metal elements such as Zn, Mg, Ca, etc., and 0≤x≤1. 3+ Metal elements with similar ionic radius replace Cr8O 21 Cr with the lowest valence state in cathode materials 3+ , does not destroy Cr8O 21 structure and improve its discharge capacity, while introducing LLZAO garnet electrolyte coating layer, on the one hand, it improves the Li + The core-shell structure modification strategy enables the chromium oxide cathode material to possess high discharge capacity, excellent rate capability, and excellent cycling stability.

The application provides an aluminum material protection water-based paint and a preparation method thereof, and belongs to the technical field of paints. A monomer A is prepared by condensation of maleic acid through an ionic liquid, and copolymerization of hexafluorobutyl acrylate hydroxyethyl ester and butyl acrylate to obtain a polymer; a solution is prepared by stirring and mixing phosphoric acid, chromium trioxide and aluminum dihydrogen phosphate; a suspension is prepared by mixing water and magnesium oxide; the suspension is added dropwise into the solution to react, magnesium powder and the polymer are added, a dispersing agent and a leveling agent are added, and the mixture is uniformly mixed to obtain the aluminum material protection water-based paint. The aluminum material protection water-based paint prepared by the application has good corrosion resistance, good adhesion, good mechanical properties and hardness, good antibacterial, flame-retardant and high-temperature resistance, improved leveling and film-forming properties of the paint, reduced coating film defects, and a wide application prospect.

The invention discloses a chromium-containing wastewater treatment and recovery treatment line and a recovery treatment method thereof. The ion exchange system is used for carrying out ion exchange adsorption on the hexavalent wastewater; the alkali washing system is used for outputting alkali liquor to the ion exchange system; the washing system is used for outputting washing water to the ion exchange system; the pickling system is used for outputting acid liquor to the ion exchange system; the chromium recovery treatment branch line is used for receiving the hexavalent wastewater of the ion exchange system, mixing the hexavalent wastewater with sulfur powder and alkali liquor to prepare chromium hydroxide, then carrying out filter pressing on the chromium hydroxide, outputting a chromium hydroxide filter cake to the recovery calcination treatment line, and outputting a press filtrate to the press filtrate recovery branch line; the press filtrate recovery branch line is used for recovering sodium thiosulfate from the press filtrate; and the recycling and calcining treatment line is used for calcining the chromium hydroxide filter cake into Cr2O3. According to the scheme, the purposes of micro discharge and even zero discharge of the chromium-containing wastewater are achieved, and the problem that a large amount of chromium-containing hazardous waste sludge is generated by depending on a chemical reduction-precipitation method in traditional chromium-containing wastewater treatment is solved.

The invention discloses a method for comprehensively utilizing vanadium and chromium resources, which comprises the following steps: mixing chromium hydroxide with sodium hydroxide, and introducing oxygen for liquid-phase oxidation to obtain an oxidation solution; adding calcium oxide into the oxidation liquid, stirring and mixing, and performing solid-liquid separation after reaction to obtain calcium vanadate solid and vanadium-free alkali liquid; adding a decalcifying agent into the vanadium-free alkali liquor, and carrying out solid-liquid separation to obtain calcium carbonate and refined sodium chromate alkali liquor; reacting calcium vanadate with roasting slurry containing aluminum, silicon and carbonate to form calcium aluminosilicate precipitate and desiliconized high-vanadium alkali liquor; continuously neutralizing the desiliconized high-vanadium alkali liquor and the carbonization solution to obtain an aluminum-vanadium high-valued product and a neutral solution; the neutral liquid is carbonized, and obtained sodium bicarbonate and carbonized liquid can be returned to a system for recycling. The method for comprehensively utilizing the vanadium and chromium resources has the advantages of being simple in process, environmentally friendly, efficient, easy to control in operation, easy to obtain raw materials, low in production cost and the like.

An object is to provide a copper-chromium oxide spinel having excellent dispersibility in a resin composition and excellent adhesion to plating, and a resin composition and a resin molded article containing the copper-chromium oxide spinel. Specifically, provided is a copper-chromium oxide spinel with a particle size distribution spread SPAN = (D90 - D10) / D50 of 2 or less where, in volume-converted particle size distribution obtained by a laser diffraction and scattering method, particle sizes with a cumulative frequency from a smaller particle size side of 10%, 50%, and 90% are D10, D50, and D90, respectively.