212 results about "Chromium oxide" patented technology

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.

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 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.

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 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 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.

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.

The invention discloses a resistor disc for a lightning arrester and a preparation method of the resistor disc. The resistor disc is prepared from the following components in parts by weight: 80-95 parts of modified zinc oxide, 3-6 parts of bismuth oxide, 1-4 parts of antimony oxide, 1-4 parts of cobalt oxide, 0.6-1.2 parts of nickel oxide, 0.6-1.2 parts of manganese oxide, 0.4-1.0 part of chromium oxide, 0.2-0.6 part of aluminum oxide and 1-4 parts of lead-free glass powder. Through two-step functional modification of the modified zinc oxide, the microstructure and macroscopic performance of the material are remarkably improved, so that the resistor disc has excellent nonlinear coefficient, low leakage current and high energy absorption capability, and the overall technical scheme not only improves the protection performance and service life of the lightning arrester, but also realizes lead-free environmental protection, energy conservation and consumption reduction, and has wide application prospects. And reliable guarantee is provided for safe and stable operation of a power system.

The invention discloses a method for stabilizing treatment of chromium-containing sludge and recovery of magnetic ferrochrome oxide, which adopts a simple solvothermal process, uses ethylene glycol as a reducing solvent, prevents Cr (III) from being oxidized into Cr (VI) in the solvothermal process, and converts iron-chromium hydroxide in the treated chromium-containing sludge into magnetic iron-chromium oxide, so that the magnetic ferrochrome oxide is recovered. The residual calcium-containing phase in the original chromium-containing sludge can be removed through an acid dissolution method, and finally the magnetic iron-chromium oxide with the calcium content lower than 2% is obtained. After treatment, the chromium content in the ethylene glycol solvent is lower than 0.2 mg / L, the next batch of sludge treatment can be carried out, and meanwhile, the chromium content in the acidic calcium ion leachate is lower than 0.9 mg / L. The method is simple in process, low in requirement on industrial equipment and low in required energy consumption, and meanwhile, the product obtained through treatment can show certain application potential in the fields of environmental protection, high-end manufacturing and the like.

The invention relates to the technical field of infrared optical materials, and particularly discloses an N-type chromium-doped high-resistance infrared silicon single crystal and a preparation method thereof. The N-type chromium-doped high-resistance infrared silicon single crystal is singly doped, the doping concentration of chromium oxide is 40-160ppm, and in the preparation process, specific constant-temperature heat treatment is carried out in a cooling stage. The concentration of free carriers in the silicon single crystal is remarkably reduced by singly doping chromium oxide and utilizing the deep energy level compensation effect of chromium element, the conduction type of the single crystal is N type, the resistivity is stably increased to above 1120ohm.cm, the average infrared transmittance of the wave band of 2-6 microns is greater than 53%, the stress birefringence is less than 3nm / cm, the process window is wide, and the operation is simple and convenient. The method is particularly suitable for preparing the silicon single crystal of a large-size and high-performance infrared optical system.

This invention discloses a chromium oxide-based coating, its preparation method, and its application. The preparation method of the chromium oxide-based coating of this invention includes the following steps: 1) dispersing ceramic particles and / or metal particles, chromium oxide particles, and a binder in water, wherein the particle size of the ceramic and metal particles is smaller than that of the chromium oxide particles, followed by spray drying to obtain composite particles; 2) thermally spraying the composite particles onto the surface of a substrate to obtain the chromium oxide-based coating. The chromium oxide-based coating of this invention possesses both high hardness and excellent toughness, exhibiting superior resistance to friction and wear, and can be used as a wear-resistant coating for the surface of metal parts, making it suitable for large-scale industrial applications.

A method for conversion of a composition containing HCFO-1233zd(Z) and HCFC-244fa to form HCFO-1233zd(E) by reacting a mixture including HCFO-1233zd(Z) and HCFC-244fa in a vapor phase in the presence of a catalyst to simultaneously isomerize HCFO-1233zd(Z) to form HCFO-1233zd(E) and dehydrohalogenate HCFC-244fa to form HCFO-1233zd(E). The catalyst may be a chromium-based catalyst such as chromium trifluoride, chromium oxyfluoride, or chromium oxide, for example.

The invention discloses a hot cathode for a vacuum device and a preparation method and application of the hot cathode. The structure of the hot cathode comprises a cathode substrate and an emission active material combined on the cathode substrate; wherein the cathode substrate is of a porous structure, and the cathode substrate is made of a mixture of chromic oxide and tungsten; and the emission active material is scandium-containing barium aluminate. According to the scheme, the problem that the requirement of a current high-power vacuum electronic device for a low-working-temperature and high-emission-current-density electron source cannot be met is well solved.

The invention belongs to the technical field of hydrogen energy resources, and particularly relates to an oxide composite coating as well as a preparation method and application thereof. The oxide composite coating provided by the invention comprises a chromium layer, a chromium / chromium oxide composite layer, a chromium oxide layer, a chromium oxide / aluminum oxide composite layer, an aluminum oxide layer, an aluminum oxide / erbium oxide composite layer and an erbium oxide layer which are sequentially stacked, the mass percentage content of chromium in the chromium / chromium oxide composite layer is reduced in a gradient manner; the mass percentage content of chromium oxide in the chromium oxide / aluminum oxide composite layer is reduced in a gradient manner; the mass percentage content of aluminum oxide in the aluminum oxide / erbium oxide composite layer is reduced in a gradient manner. A composite transition layer with gradient composition change is introduced into the interface of the substrate / oxide layer and the interface of the oxide layer / oxide layer, so that the obvious interface is eliminated, and the interlayer bonding force is greatly improved. Chromium oxide, aluminum oxide and erbium oxide are all excellent hydrogen barrier materials, the multilayer structure and the interface thereof can effectively prolong the permeation path of hydrogen, and the hydrogen permeation barrier coefficient is improved.

The application provides a 650MPa-grade ultra-supercritical high-temperature steel welding electrode and a coating and deposited metal, and belongs to the field of welding materials.The raw material of the coating comprises, in weight parts, 39-43 parts of magnesia, 30-35 parts of fluorite, 3-5 parts of dolomite, 5-10 parts of ferrosilicon, 2-5 parts of sodium titanate, 10-15 parts of metallic chromium powder, 0.1-0.4 parts of chromium oxide green, 0.1-0.3 parts of aluminum-magnesium alloy and 1.5-2.5 parts of sodium alginate.Through the research on the composition of the coating, the sodium titanate and the aluminum-magnesium alloy are added to stabilize the electric arc, the electric arc has stability and concentration when high-current welding is performed, the weld pool temperature is moderate, the fluidity of the molten iron is moderate, the electric arc blowing force is stable and concentrated, and the welding operation performance is good.

The invention discloses a hydrogenation catalyst which is a supported catalyst, the catalyst is in a particle shape, the particles are porous metal fluoride embedded with palladium element, the porous metal fluoride is selected from one or more of aluminum fluoride, chromium fluoride, magnesium fluoride, barium fluoride, calcium fluoride, aluminum fluoride oxide and chromium fluoride oxide, and the palladium element is one or more of aluminum fluoride, chromium fluoride, magnesium fluoride, barium fluoride, calcium fluoride, aluminum fluoride oxide and chromium fluoride oxide. The invention also provides a preparation method of the catalyst. According to the catalyst prepared by the method, the synthesis yield and conversion rate are high in the process of synthesizing HFC-236ea from C3F6 and synthesizing HFC-245eb from HFO-1225ye, and the product purity and yield are excellent. According to the catalyst used in the invention, aluminum oxyfluoride is used as a carrier of metal palladium, Pd particles and a carrier interface are tightly combined, and a falling sign does not appear, so that the Pd component is excellent in dispersity, and the reaction rate and the raw material conversion rate are favorably improved.

The invention relates to a rare earth doped high-temperature thermal shock resistant and corrosion resistant coating for plain carbon steel and a preparation method thereof. The coating comprises the following raw materials in percentage by weight: 5-30% of quartz sand, 2-15% of a boron-containing raw material, 1-5% of zinc oxide, 20-40% of a barium-containing raw material, 1-8% of calcium oxide, 0.5-3% of a molybdenum-containing raw material, 1-8% of bentonite, 10-40% of chromic oxide, 5-25% of cobaltous oxide and 2-8% of a rare earth raw material. The rare earth raw material comprises yttrium oxide. The coating is a glass-ceramic composite protective coating and can effectively protect a plain carbon steel substrate, the high-temperature thermal shock resistance and corrosion resistance of the plain carbon steel substrate are remarkably improved, the service life of steel is prolonged, and the comprehensive cost is greatly reduced.

This invention discloses a method for co-preparing nickel-chromium oxide pellets using laterite nickel ore and stainless steel slag, and its application, relating to the fields of metallurgical solid waste resource utilization and mineral processing technology. The method includes: raw material pretreatment: drying, crushing, and grinding laterite nickel ore and stainless steel slag to obtain laterite nickel ore powder and stainless steel slag powder with a particle size of -0.074 mm or more (more than 60%) and a D50 of 0.06 mm to 0.07 mm; pelletizing: mixing laterite nickel ore powder and stainless steel slag powder at a mass ratio of (75~85):20, and then forming pellets to obtain green pellets; oxidative roasting: the green pellets undergo preheating, roasting, and homogenization treatment to obtain nickel-chromium oxide pellets; wherein the roasting temperature is 1265℃~1285℃. The application is to use the nickel-chromium oxide pellets as a charge in a hydrogen-based vertical shaft furnace-electric furnace for stainless steel smelting. This invention solves the problems of stainless steel slag storage and comprehensive utilization of laterite nickel ore. By utilizing the complementary properties of the two materials, high-strength, high-metallurgical-performance nickel-chromium oxide pellets are obtained.

This invention relates to the field of electrochemical polishing of cobalt-based alloys, specifically to an environmentally friendly electrochemical polishing solution and polishing method for a cobalt-chromium-tungsten-nickel alloy. The cobalt-based alloy has the following chemical element mass percentages: Cr: 15.0%–25.0%; W: 10.0%–20.0%; Ni: 0.0%–15.0%; the balance being Co and unavoidable impurities such as O, N, and H. The environmentally friendly polishing solution has the following chemical composition and molar percentages: ChCl: 0.5–2 mol / L; ethylene glycol: 0.7–1.0 L; ethanol: 0–0.3 L; glacial acetic acid: 0.1–0.3 L; and a small amount of citric acid as an additive. The electrochemical polishing uses the alloy as the anode and a U-shaped titanium plate as the cathode, with a voltage of 40–60 V and a current density of 0.5–2 A / cm². 2 The polishing temperature is room temperature. The advantage of this invention is that it uses an environmentally friendly electrolyte, which can polish the surface of cobalt-chromium-tungsten-nickel alloy, avoiding the pollution of traditional chromium oxide system and acidic electrolyte system, reducing the need for repeated cleaning processes, and improving the precision control of materials.

The invention relates to a method for producing low-iron low-silicon high-quality chromium oxide green based on an electromagnetic rotary kiln, which comprises the following steps: continuously or batch-wise feeding raw materials into the electromagnetic rotary kiln, controlling the temperature in the kiln body to be 400-1100 DEG C by adjusting the current and frequency of a coil in sections, and dividing the treatment process of the materials in the kiln into a preheating section, a high-temperature reaction section, a heat preservation section and a cooling section; and staying the materials in the kiln for 3 hours, heating and calcining through heat radiation and heat conduction to generate chromium oxide green, and crushing to obtain a low-iron low-silicon high-purity chromium oxide green product. In the final product, the content of Cr2O3 can reach 99.5% or above, the content of Fe2O3 is smaller than or equal to 0.01%, the content of SiO2 is smaller than or equal to 0.1%, and the content of S is smaller than or equal to 0.003%, all indexes meet high-end application requirements, the process is accurate in control, energy-saving and environment-friendly, the structure of the rotary furnace is simplified, and the maintenance cost is low.

The present application relates to a kind of phenol gas sensor and its preparation method and application, sensor includes counter electrode (1), reference electrode (2), sensitive electrode (3), YSZ solid electrolyte layer (4) and heating sheet (5);The lower surface of the YSZ solid electrolyte layer (4) is attached heating sheet (5), the upper surface is spaced apart and provided with counter electrode (1), reference electrode (2) and sensitive electrode (3), the material of the sensitive electrode (3) is chromium oxide.Compared with prior art, the present application provides a kind of portable electrochemical sensor and its preparation method, can realize the high selectivity detection of phenol gas.

This utility model relates to the field of EVA sheet technology and discloses a wear-resistant EVA sheet for automotive applications. It includes an EVA sheet body, with a first wear-resistant layer fixedly disposed on the outer side of the EVA sheet body. A second wear-resistant layer is fixedly disposed on the side of the EVA sheet body away from the first wear-resistant layer. The first wear-resistant layer is a chromium oxide coating, applied uniformly to the outer surface of the EVA sheet body using arc spraying, with a spray thickness of 0.6–0.8 cm. The second wear-resistant layer is also a chromium oxide coating, applied uniformly to the outer surface of the EVA sheet body using arc spraying, with a spray thickness of 0.6–0.8 cm. This wear-resistant EVA sheet for automotive applications features chromium oxide coatings in both the first and second wear-resistant layers, which exhibit good coating toughness, chemical stability at high temperatures, corrosion resistance, abrasive wear resistance, and anti-wetting properties, thus improving the wear resistance of the EVA sheet body. The epoxy coatings in the first and second corrosion-resistant layers have good adhesion and chemical resistance.