56 results about "Chromium trioxide" patented technology

The invention discloses a preparation method and application of a carbon dioxide hydrogenation catalyst, and belongs to the field of hydrogenation catalysis. The vanadium slag is used as a raw material, a leaching solution containing silicon, chromium and vanadium is obtained through sodium salt roasting, an aluminum source is added to remove the silicon element, meanwhile, an ordered mesoporous carbon material is added, and silicon and aluminum elements are converted into an ordered mesoporous composite oxide which is used as a hydrogenation catalyst carrier; an indium salt, a cerium salt and a nickel salt are dissolved in ethanol and mixed with the carrier for isopyknic impregnation to obtain the hydrogenation catalyst; and carrying out chromium and vanadium separation on the silicon-removed leaching solution to obtain chromium sesquioxide and the all-vanadium redox flow battery electrolyte. The catalyst has a regular pore structure, ordered mesopores provide a confinement effect, dispersion and anchoring of active components are facilitated, and the activity of the catalyst is remarkably improved.

The application relates to the field of fireproof bricks, and discloses a baking-free fireproof brick and a preparation method thereof. The baking-free fireproof brick comprises iron tailings, cement, fly ash, a functional additive, fine aggregate, quartz sand, a chromium aluminum phosphate binder, a water reducing agent and water. The functional additive is prepared by using aluminum chloride hexahydrate and alkaline silica sol as raw materials, ammonium molybdate tetrahydrate as a catalyst, growing mullite whiskers on the surface of silicon carbide fibers through vacuum impregnation and heat treatment, modifying the prepared composite silicon carbide fibers through 3-(methacryloxy) propyl trimethoxysilane, and then copolymerizing the modified composite silicon carbide fibers with acrylic acid and 4-hydroxybutyl vinyl ether. The chromium aluminum phosphate binder is prepared by using aluminum hydroxide, phosphoric acid and chromium trioxide as raw materials and calcium hydroxide as a curing agent. The baking-free fireproof brick prepared through the synergistic effect of the components has high compressive strength and bending strength, small water absorption and good baking-free fireproof and heat insulation performance.

The present disclosure relates to the synthesis of Vitamin K2 bearing varying prenyl side chains. The synthesis comprises the reaction of phenyl sulfone of tert-butyl dimethyl silyl (TBDMS) protected mono prenyl menadiol with prenyl halides bearing varying prenyl units in the presence of the phase transfer catalyst followed by reductive desulphonation to yield TBDMS ether of Vitamin K2. The TBDMS ether is then oxidized in the presence of chromium trioxide and periodic acid to yield the corresponding Vitamin K2.

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 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 magnesium oxide-containing high-performance composite crucible for smelting an aluminum-lithium alloy and a preparation method of the magnesium oxide-containing high-performance composite crucible, and belongs to the technical field of refractory materials. The preparation method comprises the following steps: mixing aluminum oxide, calcium aluminate, boehmite, magnesium oxide, chromic oxide, calcium fluoride, modified zirconium powder, aluminum oxide and a 5wt% aluminum dihydrogen phosphate solution to obtain a mixed material, and sealing and standing the mixed material to obtain a first mixed material; adding the first mixture into a mold, and carrying out static pressure treatment to obtain a blank; and carrying out gradient sintering on the green body to obtain the magnesium oxide-containing high-performance composite crucible. According to the prepared high-performance composite crucible containing magnesium oxide, the synergistic effect of the modified zirconium powder and various functional oxides is taken as a core, and a unique process is combined, so that the corrosion resistance is improved, and the problem of material deterioration caused by high activity of lithium element is solved.

The invention discloses a high-performance Q345 composite board and a preparation method thereof.The high-performance Q345 composite board comprises a Q345R steel substrate and an embedded coating embedded in the surface of the Q345R steel substrate, the embedded coating comprises a spherical material and a Q345R steel substrate material, and the spherical material comprises, by weight, 98.91%-99.68% of a sharp crystal structure, 0.32%-0.86% of chromic oxide and 0-0.23% of nano zinc oxide. The Q345 composite board disclosed by the invention has good high-temperature strength, hydrogen embrittlement resistance and low-temperature toughness.

The invention discloses a ferrochrome liquid decarburization method based on partial roasting and step-by-step vacuum, and belongs to the technical field of ferroalloy smelting. During operation, only part of ferrochrome raw materials and powder need to be ground into powder and roasted into the endogenous oxidizing agent mainly comprising chromic oxide; then, in a vacuum induction furnace, the blocky ferrochrome and part of the oxidizing agent are molten to form a liquid molten pool, the oxidizing agent reacts with carbon in the melt through the process of combining step-by-step stepped vacuumizing and adding of the remaining oxidizing agent in batches, generated CO is rapidly pumped away by a vacuum system, and therefore deep decarburization is achieved. The method effectively solves the technical bottlenecks that a traditional oxygen blowing method cannot produce micro-carbon ferrochrome, and a vacuum solid-state method is tedious in raw material treatment and too long in decarburization period.

The invention discloses a light conversion material, an eye-protection screen protection film and a preparation method of the eye-protection screen protection film, and relates to the technical field of nano luminescent materials. The inorganic metal oxide or the inorganic non-metal oxide and the quantum dots are connected through a cross-linking material, and the inorganic metal oxide or the inorganic non-metal oxide is selected from nano silicon oxide, nano aluminum oxide, nano zinc oxide, nano zirconium oxide, nano calcium oxide, nano sodium oxide, nano manganese heptoxide or nano chromium trioxide; the particle size of the inorganic metal oxide or the inorganic non-metal oxide is 2-100 nm; the cross-linking material is selected from a silane coupling agent or a bifunctional ligand. The light conversion material and the eye protection screen protection film provided by the invention can prolong the service life of the nano luminescent material and maintain the stability of the light conversion efficiency of the light conversion material after long-term use.

The present application relates to a kind of gray glass composition and car window glass.The above-mentioned gray glass composition includes base component and coloring component, and the mass percentage of coloring component in gray glass composition is as follows: total iron Fe2O3 1.3%~2.5%, titanium dioxide TiO2 100ppm~800ppm, chromium trioxide Cr2O3 100ppm~500ppm, cobalt oxide CoO 100ppm~400ppm, selenium Se 10ppm~50ppm and tin oxide SnO2 10ppm~50ppm.The above-mentioned gray glass composition has the comprehensive performance of low visible light transmittance, low infrared transmittance, low ultraviolet transmittance, low solar direct transmittance, and also has the neutral gray tone that satisfies visual comfort, also has great economic advantage.

This invention provides a phosphate-based adhesive and its preparation method, belonging to the field of inorganic adhesives. The invention involves mixing a phosphoric acid solution with an aluminum source for an acid-base neutralization reaction to obtain a neutralized product; mixing the neutralized product with a trivalent metal halide for a metathesis reaction to obtain the phosphate-based adhesive; and providing a curing agent to obtain the phosphate-based adhesive. This invention incorporates heteroions into the aluminum phosphate adhesive system in the form of trivalent metal halides, eliminating the need for a reduction reaction and allowing direct use of the trivalent metal. The preparation method is simple, efficient, and easily scalable for industrial production. Furthermore, this invention limits the trivalent metal halide to one or more of chromium halides, iron halides, scandium halides, iridium halides, lanthanum halides, ruthenium halides, osmium halides, gallium halides, and molybdenum halides, expanding the range of heteroions and eliminating the need for highly toxic chromium trioxide, thus improving the safety of the preparation method.

This invention provides a refractory ceramic matrix material for smelting furnace linings and its preparation method, belonging to the technical field of ceramic refractory materials. The material includes coated modified fused magnesia aggregate, ceramic sand aggregate, surface-coated magnesia fine powder, γ-phase alumina micropowder, aluminum dihydrogen phosphate solution, alkaline silica sol, pre-reacted spinel precursor, and zirconium boride micropowder. The coated modified fused magnesia aggregate is prepared by mixing fused magnesia, silicon carbide composite powder, chromium trioxide powder, and phenolic resin powder, followed by sintering. Silicon carbide powder and magnesia powder are mixed, and a silicon nitride layer is deposited on the particle surface to obtain silicon carbide composite powder. The surface-coated magnesia fine powder is magnesia fine powder with alumina coated on the particle surface. The pre-reacted spinel precursor is prepared by preparing a mixed salt solution of magnesium nitrate hexahydrate and aluminum nitrate nonahydrate with deionized water, reacting, aging, and heat-treating. The ceramic sand aggregate is made of zirconium oxide. The allocation and use of each layer achieves a balanced improvement in performance.

This invention discloses a ceramic clay composition, ceramics, and their applications, relating to the field of ceramic technology. The ceramics of this invention are obtained by sequentially processing the ceramic clay composition through a process of material conditioning, sieving, casting, air drying, oven drying, and sintering. The introduction of specific proportions of ceramic waste A and B, modified particles with a gallium-coated cuprous oxide core and an alumina shell, and high-entropy oxide solid solutions generated from the reaction of hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium trioxide, and carbon powder, as well as chromium heptacarbonide, into the ceramic clay composition gives the ceramics prepared from the ceramic waste excellent fracture toughness, flexural strength, wear resistance, high-temperature resistance, and self-healing ability. Therefore, this invention has broad application prospects.

The invention is applicable to the field of preparation of rare earth ceramic pigments, and provides a preparation method of a rare earth ceramic pigment for building wall surfaces, which comprises the following steps: S1, weighing industrial neodymium oxide and aluminum oxide in equal proportion, adding water, mixing and grinding to obtain slurry A; s2, weighing yttrium oxide and aluminum hydroxide in equal proportion, adding water and chromium sesquioxide, and mixing and grinding to obtain slurry B; s3, mixing the slurry A obtained in the step S1 and the slurry B obtained in the step S2 to obtain slurry C; and S4, the slurry C is poured into a drying cylinder to be dried, a stirring mechanism is arranged in the drying cylinder to stir and heat the slurry C, and a spiral conveying mechanism in the drying cylinder drives the slurry C to be vertically conveyed. The problems that in a traditional drying process, due to the fact that the conveying speed is not matched with the heating uniformity, the drying efficiency is low, and materials are heated unevenly are solved.

The application discloses a method for separating vanadium and chromium elements from vanadium slag, which comprises the following steps: (1) roasting the vanadium slag with sodium carbonate, mixing and roasting the vanadium slag and the sodium carbonate at a certain temperature to convert vanadium and chromium elements in different valence states in the vanadium slag into the highest valence state; (2) low-temperature leaching, leaching the roasting product obtained in the first step with calcium salt and water at low temperature to obtain a calcium chromate crude liquid and a calcium vanadate leaching residue; (3) acid leaching and vanadium precipitation, separating residual chromium in the calcium vanadate leaching residue to obtain a vanadium-containing filter cake; (4) preparing vanadium pentoxide, adding water to the filter cake obtained in the third step, adding NaOH and (NH4)2SO4 to adjust the pH, and then performing water bath heating to obtain polyvanadic acid ammonium precipitate, which is dried and calcined to obtain V2O5 powder; and (5) preparing chromium trioxide, adjusting the pH of the chromium solution obtained in the second step, adding Na2SO3, reducing Cr 6+ to Cr 3+ , combining Cr 3+ with OH ‑ to form Cr(OH)3 precipitate, filtering, and calcining to obtain Cr2O3.

The application relates to the field of acetonitrile preparation, and aims to solve the problems of complicated acetonitrile impurity removal process and energy consumption, and provides a production method of a catalyst for acetonitrile preparation, which comprises the following steps: S100, 25-45 parts of pseudo-boehmite, 10-15 parts of activated carbon, 5-7 parts of chromium trioxide and 2-8 parts of P123 are mixed, then aging is carried out at 30-55 DEG C for 3-8 h, granulation is carried out to obtain a preform, and the particle size of the preform is 50-80 nm; S200, the preform is sintered at 500-550 DEG C for 2-4 h and sintered at 1100-1200 DEG C for 6-8 h to obtain a carrier; S300, 100-150 parts of the carrier, 1-3 parts of a noble metal precursor, 12-18 parts of chitosan and 600-800 parts of deionized water are mixed to obtain a mixed solution, the mixed solution is heated to reflux at 100-130 DEG C for 5-8 h under stirring, and then evaporative drying is carried out at 115-135 DEG C for 0.5-2 h to obtain the catalyst. The catalyst provided by the application can effectively inhibit the occurrence of a side reaction, reduce the ammonia gas consumption, and also can utilize the hydrophilic property of the catalyst to make the removal of an impurity layer, such as a carbon deposition layer, on the surface of the catalyst more simple during catalyst regeneration.

The application relates to a preparation method of a chromium dioxide nanowire array, and belongs to the technical field of inorganic nonmetal material preparation. The steps comprise the following: filling a chromium trioxide aqueous solution into nanopores of a porous alumina template by a vacuum impregnation method; drying the chromium trioxide aqueous solution in the nanopores of the template by a vacuum drying method; placing the dried template into an autoclave, sealing the autoclave after high-pressure pure oxygen with a pressure of 10-15 Mpa is filled into the autoclave; and heating the autoclave to 390-400 DEG C for 30 minutes, so that the chromium dioxide nanowire array is obtained. The preparation process is simple and easy to operate, and long chromium dioxide nanowire arrays can be prepared in porous alumina templates with various pore diameters.

The application relates to the technical field of acid etching agents, and discloses a hydrofluoric acid acid etching agent and a preparation method thereof, wherein the hydrofluoric acid acid etching agent comprises the following components in parts by weight: 70-75 parts of hydrofluoric acid, 40-45 parts of carrageenan, 25-30 parts of a humectant, 35-40 parts of chromium trioxide and 125-130 parts of water. Through the technical scheme, the problems of easy oxidation, complex raw materials, complicated preparation process and low stability of the acid etching agent in the prior art are solved.

The invention discloses a method for preparing a sodium sulfate solution and chromic oxide of different grades from chromium-containing sodium hydrogen sulfate, which comprises the following steps: calcining the chromium-containing sodium hydrogen sulfate at high temperature to obtain a solid product and a gas product; putting the solid product into a pulping tank, adding water, pulping and dissolving until the solid product is completely dispersed, preparing a feed liquid, and carrying out filter pressing to obtain a primary filter-pressed filter cake and an acidic solution; adding alkali into the acidic solution for neutralization, preserving heat and curing, and then carrying out filter pressing to obtain a secondary filter-pressed filter cake and a slightly acidic solution; washing and filter-pressing the primary filter-pressed filter cake, and calcining to obtain low-grade chromium sesquioxide; and washing the secondary filter-pressed filter cake, carrying out filter pressing, and calcining to obtain the high-grade chromium sesquioxide. The invention provides the method for efficiently recycling the by-product chromium-containing sodium hydrogen sulfate in the production process of chromic anhydride, the problem of poison of wastes is solved, the process is simple and easy to operate, environmental protection benefits and economic benefits are considered, and the method is suitable for industrial production.

The application provides a method for co-extracting vanadium and chromium from high-chromium vanadium slag and application thereof. The method comprises the following steps: roasting high-chromium vanadium slag and calcium salt to obtain roasted clinker, leaching the roasted clinker with a leaching agent to obtain a leaching solution, cooling the leaching solution to obtain sodium orthovanadate and a crystallization mother liquor; adding calcium oxide to the crystallization mother liquor to obtain a chromium-containing solution, performing first reduction on the chromium-containing solution to obtain chromium hydroxide, and performing first calcination on the chromium hydroxide to obtain chromium trioxide; mixing the sodium orthovanadate, water and carbon dioxide to obtain sodium metavanadate, sequentially performing transformation and second reduction on the sodium metavanadate, and performing second calcination to obtain a reduction clinker; mixing the reduction clinker, washing water and sodium bicarbonate mother liquor to obtain a sodium-containing solution and primary vanadium trioxide, and washing the primary vanadium trioxide to obtain vanadium trioxide. The application realizes high-value conversion of high-chromium vanadium slag, and simultaneously considers simplicity and economy, and no high ammonia nitrogen, high salt water and ammonia-containing waste gas are generated.

The application provides a metallographic structure display method of a gold-based alloy, and the display method comprises the following steps: taking the gold-based alloy as an anode, electrolytic immersion etching the gold-based alloy in an electrolyte composed of hydrochloric acid, nitric acid and anhydrous ethanol, then cleaning the surface of the obtained gold-based alloy to obtain the gold-based alloy after electrolytic immersion etching; soaking the gold-based alloy after electrolytic immersion etching in ammonia water, then cleaning the surface of the obtained gold-based alloy, and obtaining the gold-based alloy after preliminary treatment after the surface is dried; immersing the gold-based alloy after preliminary treatment in a corrosion liquid composed of a saturated aqueous solution of chromium trioxide, hydrochloric acid and distilled water, then cleaning the surface of the obtained gold-based alloy, and completing the display of the metallographic structure of the gold-based alloy after the surface is dried, which greatly facilitates the observation of the metallographic structure of the gold-based alloy and is beneficial to obtaining the gold-based alloy product meeting the performance requirements.

The invention provides a mesoporous high-entropy chromium-nickel-based metal oxide material and a preparation method thereof, and belongs to the technical field of electrode materials. The preparation method comprises the following steps: ball-milling and mixing chromium trioxide and nickel oxide serving as main raw materials and a proper amount of metal oxide active agent, and then drying in vacuum; heat preservation heat treatment; and washing with water, washing with alcohol, drying, and finally screening to obtain the mesoporous high-entropy chromium-nickel-based metal oxide material. The mesoporous high-entropy chromium-nickel-based metal oxide material is prepared by the method. The chromium-nickel-based metal oxide material can be obtained through one-time heat preservation heat treatment, and the working procedure is simple; the prepared chromium-nickel-based metal oxide material belongs to a high-entropy material, is beneficial to improvement of water resistance and heat resistance by doping cerium, gadolinium, rhodium, magnesium, aluminum and other metal elements, has small particle size and mesoporous structure and large specific surface area, and can greatly improve the diffusion coefficient of a lithium ion body phase, thereby obtaining excellent power rate performance.

The application discloses a preparation method of 4N high-purity chromium, and comprises the following steps: step one, adding metal chromium into concentrated sulfuric acid mixed with water for leaching; step two, adopting a Mohr salt method; step three, obtaining a chromium (III) solution through extraction; step four, performing alkaline precipitation on the chromium (III) solution, and obtaining chromium hydroxide through filtration; step five, performing roasting on the chromium hydroxide, and obtaining chromium trioxide; step six, mixing the chromium trioxide with aluminum particles and a heating agent, and sequentially performing vacuum aluminothermic reduction and vacuum suspension smelting to obtain 4N chromium. The preparation method shortens the preparation period under the premise of ensuring the iron removal effect by adopting the process of the Mohr salt method combined with extraction of iron, and effectively reduces the impurity content of gas, iron and the like by adopting the process of vacuum aluminothermic reduction combined with vacuum suspension smelting, so that 4N chromium is obtained, and the method is suitable for the technical field of high-purity metal chromium preparation.

The preparation method is innovated according to the pyrolytic reaction characteristics of chromium trioxide, such as a heat absorption phenomenon and an oxygen evolution phenomenon in a pyrolytic process, which bring serious negative effects on the temperature field uniformity and heat balance of a reaction site and further affect the reaction process and phase uniformity of a product; the invention particularly relates to a preparation method and application of a porous composite positive electrode material suitable for a lithium primary battery. And the metal oxide with high heat conductivity coefficient is used for promoting the temperature field uniformity of the reaction and providing a reaction interface of the pyrolytic reaction, so that the phase uniformity of the target product and the consistency of batch performance are improved. Besides, thermal oxygen desorption is a favorable condition for pore forming, the reaction condition and the phase conversion process of the reaction are controlled through a two-step roasting method, and the porous characteristic of the positive electrode material is adjusted, so that the power characteristic and the capacity exerting efficiency of the positive electrode material are further improved, and an effective material modification method and a control method for the batch stability of the material are provided.

The invention discloses a method for separating vanadium and chromium ions in vanadium slag water leaching liquid, and belongs to the technical field of metallurgical chemical engineering, the method comprises the following steps: by taking the water leaching liquid obtained after sodium salt roasting of vanadium slag as raw material liquid, removing silicon, adjusting pH, adding a reducing agent to selectively reduce hexavalent chromium into trivalent chromium, and then adsorbing chromium in the solution by using cation exchange resin, thereby obtaining the vanadium and chromium ions in the vanadium slag water leaching liquid. Vanadium in the solution is subjected to vanadium precipitation to obtain vanadium pentoxide, then chromium on the resin is desorbed with an acid solution, the pH of the desorption solution is adjusted to form chromium precipitate, and chromium trioxide is obtained after roasting. According to the method, through collaborative innovation of selective reduction, strong acid cation exchange directional adsorption and an organic solvent-free process, the problems of incomplete separation of vanadium and chromium, low recovery rate and high cost in a traditional method are solved, efficient recovery of high-purity vanadium and chromium products is realized, and the method has both environmental protection property and economical efficiency.

This invention discloses a layered chromium-based cathode material for sodium-ion batteries and its preparation method, wherein the cathode material has the general formula NaCr. 1‑x M x O2, wherein M is Ti, V, Mn, Fe, Co, Ni, Mg, Zn, Ir or Cu, and 0.01≤x<0.1; the cathode material is granular with a particle size of 1-10μm, has a trigonal crystal structure, and exhibits no phase transition characteristics; the preparation process includes mixing sodium salt, chromium trioxide and metal oxide, pressing them into sheets, and then calcining them at 700-1000℃ for 8-12h in an inert atmosphere to obtain a layered chromium-based cathode material for sodium-ion batteries; this invention, by controlling the element ratio and high-temperature sintering reaction conditions, allows the precursors to diffuse into each other at high temperatures to form a continuous solid-state layered structure, thus preparing a sodium-containing trigonal layered oxide, which exhibits no phase transition characteristics during charging and discharging over a wide voltage range, has small volume changes during charging and discharging, and combines excellent electrochemical structural stability with air stability, significantly improving battery cycle life.

This invention provides a high-entropy perovskite-type high-temperature negative temperature coefficient thermistor ceramic, its preparation method, and its application, belonging to the field of perovskite semiconductor materials. This series of high-temperature negative temperature coefficient thermistors involves mixing lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, and chromium trioxide with oxides of lanthanum oxide (La), followed by wet three-dimensional vibration ball milling, powder calcination, cold isostatic pressing, and high-temperature sintering to obtain a perovskite structure (La). 0.2 Nd 0.2 Sm 0.2 Eu 0.2 A 0.2 )CrO3 thermistor material, where A is one of Pr, Tb, Dy, Ho, Er, Yb, Lu, and Y. The electrical performance parameters of the series of materials prepared in the examples were determined as follows: B 25℃ / 1500℃ =1625K~1742K, ρ 1500℃ =7.48×10 2 Ω·cm~7.75×10 2 The material exhibits excellent negative temperature coefficient characteristics within the temperature range of 25℃ to 1500℃ and demonstrates high-temperature aging stability. The high-entropy perovskite-type high-temperature negative temperature coefficient thermistor ceramic of this application has an upper limit of applicable temperature up to 1500℃, high resistance-temperature linear correlation, and good consistency, making it suitable for manufacturing high-temperature thermistor components.

This invention discloses a microcrystalline glass, its preparation method, a cover glass, and an electronic device, belonging to the field of new materials. The composition of the microcrystalline glass is as follows (by mass percentage): SiO₂ 60-80%, Al₂O₃ 1-10%, Li₂O 10-18%, ZrO₂ 3-12%, Na₂O 0-5%, CaO 0-4%, P₂O₅ 1-5%, K₂O 0-3%, Cr₂O₃ 0-10%, Fe₂O₃ 0-10%, where Cr₂O₃ and Fe₂O₃ are not both 0 and 1.9wt%≤Cr₂O₃+Fe₂O₃≤10wt%, the crystalline phase contains a crystal phase that produces a gold-like effect. The crystal phase that produces the gold-like effect is chromium trioxide crystal, or iron oxide crystal, or chromite spinel, or chromium trioxide crystal and chromite spinel.

The application relates to the field of electronic materials, and particularly discloses a low-gradient zinc oxide varistor disc and a preparation method thereof; the low-gradient zinc oxide varistor disc comprises the following raw materials in parts by weight: 88-96 parts of zinc oxide, 1.5-3 parts of diantimony trioxide, 2-5 parts of bismuth trioxide, 0.2-1.8 parts of nickel oxide, 0.1-0.9 parts of cobalt trioxide, 0.1-0.4 parts of manganese oxide, 0.02-0.07 parts of chromium trioxide, 0.15-0.18 parts of lithium acetate, 1.2-1.8 parts of a dispersing agent, 1.8-2.5 parts of a binding agent, 0.12-0.15 parts of aluminum nitrate and 0.001-0.003 parts of silver nitrate; under the synergistic action of the components, the use ratio of the components is adjusted, the potential gradient of the varistor disc is reduced, the large-current resistance of the varistor disc is improved, and the change of the electrical performance after impact is reduced.