1880 results about "Cerium" patented technology

The invention relates to the technical field of smashing, and discloses a cerium oxide airflow smashing device and a production technology.The cerium oxide airflow smashing device comprises a base, four supporting legs arranged at equal angles are arranged on the base, a first tank is connected to the supporting legs, and an air injection mechanism used for spraying high-pressure airflow and driving materials to collide with one another to be smashed is installed in the first tank; a feeding pipeline positioned above the air injection mechanism is mounted on the first tank body; the inner wall of the first tank body is provided with four cooling assemblies which are arranged at equal angles, the upper port of the first tank body is connected with a second tank body through a flange, the second tank body is provided with a grading mechanism and a discharging pipeline corresponding to the grading mechanism, and the upper port of the second tank body is provided with a top cover; according to the device, efficient production is achieved through multi-dimensional innovation, a double-layer S-shaped cooling flow channel dissipates heat quickly, and high-temperature agglomeration of materials is avoided so as to guarantee stable physicochemical properties; and the four groups of opposed nozzles form a vortex field, so that the particle size refining rate of the material is more than 90%, and the energy consumption is reduced by 35%.

The invention belongs to the technical field of adsorbent preparation, and relates to a preparation method of a series of M-TCBB metal organic framework materials and application of the M-TCBB metal organic framework materials to adsorption of sulfur dioxide and ammonia gas. The preparation method comprises the following steps: dispersing [9, 9 '-dicarbazole]-3, 3', 6, 6 '-tetracarboxylic acid (H4TCBB) serving as an organic ligand and any one or more of yttrium salt, zirconium salt, hafnium salt, cerium salt and thorium salt in a solution according to a certain mass ratio, and carrying out solvothermal reaction at 100-120 DEG C; and after the reaction is finished, centrifuging to take a precipitate, washing and drying to obtain a series of M-TCBB metal organic framework materials. The series of M-TCBB metal organic framework materials prepared by the invention have relatively good adsorption acting force on sulfur dioxide and ammonia gas, and are high in adsorption cycle stability; under a humid condition, capture of sulfur dioxide and ammonia gas shows a humidity enhancement characteristic, namely, water vapor promotes enhancement of the adsorption capacity of sulfur dioxide and ammonia gas.

The invention discloses a neodymium-iron-boron magnet with double main phases and light rare earth diffusion based on asymmetric cerium distribution and a preparation method, and relates to the technical field of neodymium-iron-boron magnets. The method comprises the steps that a diffusion matrix is prepared through a double-main-phase technology, in the double-main-phase technology, the components of a main-phase alloy and an auxiliary-phase alloy are RaCebFe100-a-b-c-dMcBd, R is PrNd alloy or Nd metal, M is at least one of Cu, Al, Zr, Co and Ga, the content of Ce in the main-phase alloy is larger than that of Ce in the auxiliary-phase alloy, then the upper surface and the lower surface of the diffusion matrix are coated with a diffusion source solution, and the diffusion matrix is obtained through heat treatment. Carrying out heat treatment and aging treatment to obtain a neodymium-iron-boron magnet; the diffusion source solution is formed by mixing a diffusion source and a solvent, and the diffusion source is (PrmNdn) aAlbCucZrdCoeMgf. The neodymium-iron-boron magnet obtained through the method has high residual magnetism and high coercive force at the same time, the diffusion efficiency of the diffusion source is high, and the rare earth utilization rate is increased.

The present invention discloses a medium-high performance neodymium iron boron and a preparation method thereof. Through the master-slave phase double alloy process, the master phase alloy is cerium iron boron with a low total rare earth content, and the slave phase is a neodymium iron boron alloy with a high total rare earth content, avoiding the entry of light rare earths in the master phase into the grain boundaries, while the surplus rare earths in the slave phase enter the grain boundaries and are recombined into rare earth-rich phases. The prepared magnet is processed into a thin magnetic sheet, and a low-melting-point HReM alloy is magnetron sputtered, realizing low-temperature grain boundary diffusion. This alloy improves the grain boundary wettability and also improves the fluidity of the rare earth-rich phase, enabling the cerium-containing neodymium iron boron master and slave phase grains to be quickly isolated during grain boundary diffusion. The low-temperature diffusion avoids the replacement of the diffused heavy rare earths by praseodymium, neodymium, and cerium elements, inhibits the exchange coupling between cerium iron boron grains, and makes the heavy rare earths free in the grain boundaries or interact with the rare earth-rich phase to form a core-shell structure on the surface layer of the master phase grains, enabling the rare earth-rich phase to be continuously and uniformly distributed, effectively enhancing the effectiveness of the grain boundary diffusion of heavy rare earth elements in improving the intrinsic coercivity of the cerium-containing magnet.

The invention discloses a high-oxygen-storage zirconium solid solution material and a preparation method, and belongs to the technical field of rare earth catalytic materials, and the method comprises the following steps: precursor preparation, ultrasonic dispersion, double-gradient precipitation, ultrasonic aging, solid-liquid separation, three-section roasting and furnace cooling. Through the synergistic effect of double-gradient precipitation and ultrasonic aging, coarse grains and non-uniform particle size distribution are avoided, and the material is not prone to abnormal growth of the grains and structural collapse in long-term high-temperature service. Meanwhile, according to the gradient roasting process, through step-by-step regulation and control of crystal densification and crystal lattice reconstruction, separation of a fluorite phase and a pyrochlore phase easily occurring in traditional low-temperature single-section roasting is reduced, a stable crystal phase structure is maintained, it is ensured that the material can still keep sufficient active surface and pore channel structures under the working conditions of high temperature and thermal shock alternation, and the performance of the material is improved. The oxygen storage capacity and the long-term durability of the catalyst carrier are obviously improved.

The invention belongs to the technical field of stainless steel surface treatment, and particularly relates to a stainless steel passivation solution and a preparation method thereof. The water-based cutting fluid is prepared from the following raw materials: cerium salt, copper sulfate, citric acid, sodium dihydrogen phosphate, ammonium molybdate, sodium tungstate, aminated-silane modified SiO2 nanoparticles, polyethylene glycol, L-ascorbic acid, polyaspartic acid, an anti-settling agent, a surfactant and the balance of deionized water. According to the invention, a three-dimensional network skeleton is constructed by using aminated-epoxy group silane modified SiO2 nanoparticles, so that the problem of weak interface bonding force of a traditional passivation layer is solved; according to the formula, the proportion of biodegradable components such as citric acid and polyaspartic acid is extremely high, cerate adopts a low-toxicity rare earth compound, molybdenum / tungsten elements are fixed in a stable oxide form, the dosage of EDTA is remarkably reduced through a compounding technology, residual ions are adsorbed in combination with a three-dimensional network, and the balance of environment friendliness and long-acting corrosion resistance is achieved.

The present invention relates to the technical field of tungsten alloy materials, and in particular to a tungsten alloy wire, and a preparation method therefor and a use thereof. The tungsten alloy is composed of the following elements in percentage by mass: 0.45-0.9 wt% of L, 0.05-0.2 wt% of oxygen, and the balance being tungsten and inevitable impurities, wherein L is one or more of lanthanum, cerium, praseodymium, neodymium, gadolinium, and samarium, the wire has a wire diameter of 20-60 μm, in the wire, L or compounds of L exist in the axial direction of the wire in a linear shape, and the average width D of L or the compounds of L in the radial direction is less than or equal to 5 nm. The element L is controlled to be doped between the tungsten base materials in a linear shape, and the average width D of L in the radial direction to be less than or equal to 5 nm, so that cracks and wire breakage caused by second-phase particles in the subsequent pressure machining process are greatly reduced, thereby guaranteeing the mechanical strength of the tungsten alloy wire, and thus the wire has a tensile strength of 5000 MPa or above under a wire diameter of 20-60 μm, and the machining performance of the tungsten alloy wire is enhanced.

The invention relates to the technical field of metal materials, and discloses a light high-strength zinc alloy and a preparation method and application thereof.The zinc alloy takes aluminum and magnesium as main alloy elements, scandium-yttrium pre-alloying components, cerium-lanthanum composite rare earth and a nano TiB2 particle reinforced phase are introduced, and grain refinement and interface strengthening are achieved through the synergistic effect of multiple components; the preparation method comprises the key processes of pre-alloy smelting, dynamic magnetic field assisted die casting, gradient aging treatment and the like, and the defects of melt oxidation and solidification are effectively controlled. The zinc alloy has low density, high specific strength, corrosion resistance and excellent surface treatment adaptability, is suitable for manufacturing of precise metal fasteners such as belt buckles, belt buckles and shoe buckles, can remarkably improve the anti-fatigue performance and appearance quality of products, meanwhile, reduces processing energy consumption and material loss, and meets the market requirements of light-weight and high-end hardware fittings.

The invention provides a cerium oxide photo-thermal synergistic catalytic material loaded with a metal promoter as well as a preparation method and application of the cerium oxide photo-thermal synergistic catalytic material. The cerium oxide photo-thermal synergistic catalytic material loaded with the metal promoter comprises a cerium oxide nanocrystal and the metal promoter loaded on the surface of the cerium oxide nanocrystal, the exposed crystal face of the cerium oxide nanocrystal comprises a {111} crystal face, and the area of the {111} crystal face accounts for more than 50% of the total area of the outer surface of the crystal face; the mass fraction of the metal cocatalyst is 0.1-2wt% of the mass of the cerium oxide. The catalytic material provided by the invention takes cerium oxide with a {111} crystal face as an exposed special crystal face as a carrier, photons can be captured and charges can be separated more efficiently, and phonons further promote deep trap state charge release. Meanwhile, the metal additive is added and cooperates with cerium oxide with exposed special crystal faces for catalysis, so that the catalytic effect is remarkably improved, and efficient catalytic combustion of methane is achieved under the mild condition.

The invention provides a cerium oxide-loaded mesoporous carbon sphere material and a preparation method and application thereof, and belongs to the technical field of cerium oxide composite material preparation, and the preparation method comprises the following steps: carrying out a hydrothermal reaction on cerium salt under the action of an alkaline mesoporous carbon sphere aqueous solution to obtain a mixed solution; the mass fraction of the mesoporous carbon spheres in the mixed solution is 1-4 wt%, and the concentration of the cerium salt is 0.04-0.06 mol / L; and carrying out centrifugal washing on the obtained mixed solution, and carrying out vacuum drying to obtain the cerium oxide loaded mesoporous carbon sphere material. The mesoporous carbon sphere has a large specific surface area and a uniform pore structure, the pore structure of the mesoporous carbon sphere is very close to the diameter of the short rod type CeO, and the short rod type CeO can be embedded into the pore of the mesoporous carbon sphere due to the size matching, so that tight physical contact is formed; meanwhile, hydroxyl groups on the surfaces of the carbon spheres and oxygen vacancies on the surfaces of the CeO particles can form stable covalent bonds, so that the bonding strength of the cerium oxide-loaded mesoporous carbon spheres is improved, and the service life of the cerium oxide-loaded mesoporous carbon spheres is prolonged.

The invention discloses a synthesis method of a hydrazine dicarboxylate modified cerium dioxide abrasive, and belongs to the technical field of precise polishing materials. The method comprises the following steps: taking cerous nitrate as a raw material, and preparing a cerous carbonate precursor through an ammonium carbonate precipitation reaction; and grinding and calcining the obtained precursor and hydrazine dicarboxylate to obtain the CeO2 grinding material with the surface rich in oxygen vacancies. And Ce < 4 + > can be partially reduced into Ce < 3 + > by reducing fragments generated by decomposition of the hydrazine dicarboxylate in the calcining process, so that an oxygen vacancy structure is formed through induction, and the chemical activity and the reaction rate of the abrasive are improved. The obtained grinding material shows excellent performance in chemical mechanical polishing (CMP) of K9 glass, the material removal rate (MRR) is increased by about 3.6 times compared with that of unmodified CeO2, the surface roughness (Ra) is reduced to about 0.16 nm or below, and grinding material particles are good in dispersity and less in agglomeration. The used hydrazine dicarboxylate is stable, low in toxicity and mild in reaction, and the particle size can be prevented from excessively growing while the high oxygen vacancy concentration is kept.

The invention discloses a blue-and-white glaze and a preparation method and application thereof, and belongs to the technical field of inorganic non-metallic materials (ceramics), the blue-and-white glaze comprises quartz, feldspar, limestone, plant ash and other basic raw materials, zinc oxide, aluminum oxide, lanthanum oxide, cerium oxide and other rare earth elements, and a modified organic additive is introduced. Compared with the prior art, the blue-and-white glaze shows excellent stability in the drying and firing process, the phenomena of cracking and glaze stripping are effectively reduced, the friction coefficient after firing is low, the breaking strength and the breaking modulus are high, the glossiness and transparency of a glaze surface are remarkably improved, and the blue-and-white glaze has important application value.

The invention provides a low-cost high-specific-surface-area cerium-aluminum composite oxide, a preparation method and application thereof, and relates to the technical field of catalysts, the preparation method comprises the following steps: step S1, adding 10-40% of cerium salt, 50-90% of aluminum salt and 0-10% of lanthanum source or zirconium source into deionized water, stirring and mixing, filtering, and washing to be neutral to obtain a cerium-containing solution; step S2, impregnating an alumina carrier in the cerium-containing solution prepared in the step S1, and standing to enable the cerium-containing solution to be impregnated on the alumina carrier, so as to obtain impregnated slurry; and S3, drying the dipping slurry, and then roasting in an inert atmosphere to obtain the cerium-aluminum composite oxide. The stable cerium-aluminum composite material is formed by doping one of lanthanum and zirconium with different masses into aluminum oxide or cerium oxide, the problem that the adsorption capacity of a traditional ammonia trapping method is limited is effectively solved, and the adsorption capacity of the material to ammonia is remarkably improved.

The invention relates to the technical field of copper alloys, in particular to a high-conductivity wear-resistant copper alloy and a preparation method and application thereof. A high-conductivity wear-resistant copper alloy comprises, by mass, 3-6% of nickel, 2-5% of tin, 1-3% of zinc, 0.1-0.5% of a rare earth element, 0.8-1.2% of a carbon nanotube-copper intermediate alloy and the balance copper, the rare earth element is one of cerium and lanthanum, the conductivity of the high-conductivity wear-resistant copper alloy is larger than or equal to 94% IACS, and the Vickers hardness of the high-conductivity wear-resistant copper alloy is larger than or equal to 120 HV. By regulating and controlling the mass ratio of nickel (Ni) to tin (Sn), adding the rare earth element and the carbon nanotube-copper intermediate alloy and accurately controlling the preparation process, the conductivity, wear resistance and mechanical property of the copper alloy material are remarkably improved, and the copper alloy material has wide application prospects in the fields of power transmission, high-speed transportation, ocean engineering and the like.

The invention relates to the technical field of metal material hot working, and discloses a hot-rolled coiled plate production process which comprises the following steps: preparing a reaction type protective agent, the high-temperature-resistant coating is prepared from the following raw materials in parts by weight: 20 to 40 parts of tetraethoxysilane, 5 to 15 parts of triethyl phosphate, 1 to 5 parts of triethyl borate, 0.5 to 2.0 parts of cerous nitrate (III) hexahydrate, 0.1 to 1.0 part of lithium acetate and 0.01 to 0.05 part of vanadyl acetylacetonate (IV). Coating the surface of a hot-rolled plate blank with the protective agent; the coated plate blank is heated in a heating furnace, so that the protective agent forms a molten-state protective layer in situ; carrying out hot rolling on the plate blank with the molten protective layer; and cooling and coiling the hot-rolled steel strip. In the whole heating and hot rolling process, the molten protective layer isolates the contact between the steel and the oxidizing atmosphere, so that the generation of oxide scales is fundamentally inhibited, the production process is simplified, and the metal yield is increased.

The invention discloses a coating with in-situ plugging and active protection functions as well as a preparation method and application thereof, and belongs to the technical field of metal material surface treatment. An innovative electrolyte design scheme is provided, the commercial 5083 aluminum alloy is subjected to micro-arc oxidation in a phosphate system containing specific cerium salt and a complexing agent, film layer growth and in-situ chemical blocking of micropores are completed in one step, the process is simple, and the obtained coating has excellent blocking firmness and corrosion resistance, has an active protection function and is suitable for large-scale industrial production. And a new solution is provided for improving the durability of the 5083 aluminum alloy in a harsh marine environment.

The invention relates to the technical field of explosion suppression, in particular to a composite powder explosion suppressant and a design method and a preparation method thereof. The composite powder explosion suppressant is prepared from the following components in parts by mass: 20 to 25 parts of aluminum oxide, 10 to 20 parts of magnesium oxide, 20 to 30 parts of silicon dioxide, 1 to 3 parts of cerium oxide, 10 to 15 parts of potassium bicarbonate, 10 to 15 parts of sodium bicarbonate, 3 to 8 parts of gas-phase hydrophobic white carbon black and 2 to 6 parts of talcum powder. The composite powder explosion suppressant disclosed by the invention is high in explosion suppression efficiency; the metal oxide component screened through quantum chemistry calculation has good explosion suppression performance, and all the components in the composite powder explosion suppressant have a synergistic effect, so that hydrogen explosion can be effectively inhibited.

The invention belongs to the technical field of neodymium iron boron rare earth permanent magnets, and relates to a cerium-containing neodymium iron boron magnet with high coercivity and high stability and a preparation method thereof. According to the preparation method, the cerium-containing copper auxiliary alloy and the neodymium iron boron magnetic powder are ingeniously combined, the whole preparation process is optimized, and remarkable technical progress and economic benefits are achieved. Firstly, in the aspect of magnetic performance, Ce in a specific proportion is added into the cerium-containing copper auxiliary alloy, the cerium-containing copper auxiliary alloy is used, the coercive force of a magnet is effectively improved, high residual magnetism is kept to a certain degree, and introduction of Cu is beneficial to refining of grains and improvement of a grain boundary phase structure; therefore, the reverse magnetization resistance in the magnet is enhanced, and the magnet can maintain stable performance in a wider temperature range.

The invention relates to the technical field of chemical catalysts, in particular to a cerium-based solid solution loaded iron-based oxygen vacancy enhanced low-temperature ammonia synthesis catalyst. The heterovalent ions are doped in CeO2 crystal lattices to introduce strain and defects, so that the oxygen vacancy formation energy and concentration are greatly improved. Experiments show that the oxygen vacancy concentration (delta) of the Ce0. 8Zr0. 2O2-delta carrier disclosed by the invention can reach 0.12, which is 3-5 times that of pure CeO2. Under the conditions of 250 DEG C and 5 MPa, the ammonia synthesis rate reaches 120 [mu] mol / g / h, which is more than 20 times that of a traditional molten iron catalyst; under the conditions of 350 DEG C and 10 MPa, the ammonia synthesis rate exceeds 1000 [mu] mol / g / h and is close to the level of a noble metal ruthenium-based catalyst. As the working temperature is reduced by 100-150 DEG C, the reaction heat consumption is reduced by more than 30%, and the overall energy consumption is reduced by 25-40%.

The invention discloses a preparation method of a rare earth element doped nickel-based selenide nano-material and application of the rare earth element doped nickel-based selenide nano-material in electro-catalysis water full-hydrolysis reaction. According to the method, nickel salt, cerium salt, selenium dioxide and potassium chloride are prepared into electrolyte, and the electrolyte is subjected to electro-deposition on a foamed nickel substrate to obtain Ce-doped Ni0.85Se nanoparticles growing on foamed nickel. The crystal structure and electron distribution of Ni0.85Se are optimized by doping trace rare earth element cerium, so that the HER and OER performances of the Ni0.85Se are greatly improved. The prepared catalyst is self-supporting closely-packed nanoparticles, the formed amorphous structure is easy to expose more active sites, the catalyst has good electrocatalytic hydrogen evolution and oxygen evolution performance under alkaline conditions, the overpotential in electrocatalysis of nickel-based selenide is greatly reduced, and the electrocatalytic performance of nickel-based selenide is improved. And excellent electro-catalytic activity is shown in electro-catalytic water full hydrolysis. And the self-supporting electrode is not easy to fall off due to generation of bubbles in the reaction process, so that the working stability of the catalyst is improved.

The method comprises the following steps: weighing an oxide precursor of metal indium, an oxide precursor of metal M, an ammonium salt and a lithium salt according to a chemical formula of indium-based halide, fully mixing, and calcining in an inert atmosphere to obtain the indium-based halide solid electrolyte. Forming an indium-based halide solid electrolyte through a solid-phase reaction; wherein M is selected from at least one of magnesium, calcium, strontium, barium, aluminum, gallium, indium, bismuth, scandium, yttrium, zinc, germanium, tin, lanthanum, cerium, samarium, gadolinium, holmium, erbium and ytterbium. The method can greatly simplify the synthesis process, reduce the raw material cost and realize industrial batch preparation.

The preparation method of the rare earth antibacterial glaze comprises the following steps: mixing 30-48 parts by mass of quartz sand, 20-35 parts by mass of borax, 25-35 parts by mass of feldspar powder and 10-25 parts by mass of zinc oxide into a ball mill for ball milling, sieving the ball-milled material, and drying to obtain powder A; mixing 0.5-3 parts of lanthanum oxide, 0.5-2 parts of cerium oxide and 100 parts of powder A into a ball mill for ball milling, and sieving and drying the ball-milled material to obtain powder B; melting the powder B at 1350-1400 DEG C to obtain a glaze melt, taking out the glaze melt, tabletting, and cooling to obtain a glaze frit; and carrying out ball milling on the glaze frit until the particle size is less than 20 microns, slowly heating to 650-700 DEG C, and carrying out heat preservation for 25-30 minutes to obtain the rare earth antibacterial glaze. The ceramic prepared from the rare earth antibacterial glaze has broad-spectrum antibacterial performance, inhibits the breeding of microorganisms such as bacteria and fungi, and reduces the infection risk.

The invention discloses a preparation method of monodisperse nano cerium oxide, and relates to the technical field of rare earth materials. The preparation method of the nano cerium oxide comprises the following steps: S1, adding hydrogen peroxide and a surfactant into a cerium salt solution, and uniformly stirring and mixing to obtain a pre-solution; s2, the pre-solution is adjusted to be in an alkaline environment through an alkaline solution, stirring is conducted for 0.5-1.5 h at the temperature of 60-90 DEG C, slurry is obtained, then suction filtration, washing, drying and calcination are conducted, and cerium oxide powder is obtained. The prepared nano cerium oxide particles are small in particle size, narrow in particle size distribution range and good in dispersity.

A particulate oxide composition comprising cerium oxide, trivalent dopant, and optional additional metal oxide, other than cerium oxide and trivalent dopant, is beneficial to aid in the removal of biological contaminants, such as bacteria, viruses, fungi, protozoa (e.g., amoebae), yeast and algae. This particulate oxide composition contains more cerium oxide than trivalent dopant and has a unique depth profile in which the average trivalent dopant to Ce ratio at about 0 nm to about 3.5 nm from the surface of the particulate composition is greater than the trivalent dopant to Ce ratio at about 15 nm from the surface of the particulate composition. These trivalent doped cerium oxide compositions can be used to remove these biological contaminants from fluids, including air and water, and from solid surfaces. Also described are methods of using compositions containing these trivalent doped cerium oxide compositions to remove biological contaminants.

The invention relates to the field of material science and mechanical engineering, in particular to a high-strength aluminum-magnesium-silicon material bolt for a new energy automobile and a preparation method of the high-strength aluminum-magnesium-silicon material bolt. The bolt is made of an aluminum-magnesium-silicon alloy, and the alloy contains magnesium, silicon, manganese, iron, chromium, titanium, scandium, rare earth elements and the balance of aluminum. By optimizing the proportion of rare earth elements (yttrium, lanthanum and cerium) and scandium, grains are effectively refined, the tensile strength, the yield strength and the ductility are improved, and meanwhile the corrosion resistance and the fatigue resistance are enhanced. The preparation method comprises the steps that vacuum melting is combined with the ultrasonic-assisted technology, alloy elements are evenly distributed, and then the material structure is optimized through solution treatment at the temperature of 540 DEG C for 1.5 h and aging treatment at the temperature of 160 DEG C for 8 h. And the surface of the bolt is subjected to anodic oxidation and coated with a composite coating containing silicon dioxide nanoparticles, so that the wear resistance and the corrosion resistance are improved. Through verification, the bolt has the excellent performance that the tensile strength is larger than or equal to 490 MPa, the yield strength is larger than or equal to 440 MPa, the ductility is larger than or equal to 8.5%, and the salt spray test time is larger than or equal to 1500 hours, and the fastening requirement of the new energy automobile under the complex working condition is met.

The invention relates to the technical field of metal material manufacturing, and discloses a manufacturing process of a super-strong wear-resistant tire protection chain, which comprises the following steps of: forming a chain link blank by adopting high-silicon high-manganese bainite steel through hot rolling and hot die forging; the core of the method is an integrated heat treatment step, specifically, surface functionalization co-permeation of copper and cerium elements is synchronously carried out in the austenitizing stage, then bainite isothermal quenching is carried out, and a composite structure of bainite and stable retained austenite is obtained in a matrix; the process further comprises the steps that a special high-toughness welding wire is adopted for welding, and local tempering treatment is conducted on a welding seam; by means of the scheme, the chain link is endowed with excellent obdurability and fatigue resistance through the phase transformation induced plasticity effect of the base body, the abrasion resistance is remarkably improved through the surface functionalization co-cementation layer, and the reliability of a joint area is ensured through accurate welding and postweld treatment. The technical problems that wear resistance and toughness of a traditional protection chain are difficult to consider at the same time, and a welding joint is prone to failure are systematically solved.

The invention belongs to the technical field of powder metallurgy, and particularly relates to a high-toughness hard alloy and a preparation method and application thereof.The preparation method comprises the steps that tungsten powder is subjected to high-energy ball milling, and then treated tungsten powder is obtained; the preparation method comprises the following steps: dissolving water-soluble lanthanum salt, cerium salt and chromium salt, and performing spray drying to obtain La-Ce-Cr composite powder; the treated tungsten powder, titanium dioxide powder, cobalt powder, La-Ce-Cr composite powder and carbon powder are mixed, and mixed powder is obtained; sintering the mixed powder to obtain alloy powder; the tungsten carbide and the alloy powder are flexibly mixed, and a mixture is obtained; and pressing and sintering the mixture to obtain the high-toughness hard alloy. The high-toughness hard alloy is a plate-shaped crystal hard alloy and is uniform in organization structure, the hardness HV10 is larger than or equal to 1620, and the fracture toughness KiC is larger than or equal to 24 MPa.m < 1 / 2 >.

The present invention relates to an ammonia decomposition catalyst and a manufacturing method thereof, and more particularly to an ammonia decomposition catalyst containing alumina (Al2O3), cerium (Ce), lanthanum (La), ruthenium (Ru) and potassium (K).

A sensor comprising one or more metal oxides as sensor material is used to detect pathogen-derived VOCs, such as those released from an infected wound. The metal oxides can comprise one or more metal elements selected from aluminum, antimony, bismuth, boron, cerium, chromium, cobalt, copper, gold, indium, iridium, iron, lanthanum, lead, manganese, molybdenum, nickel, niobium, osmium, palladium, platinum, rhodium, ruthenium, selenium, silicon, silver, tantalum, tellurium, terbium, tin, titanium, tungsten, vanadium, ytterbium, yttrium, zinc, and zirconium. The sensor device can have one or more sensors that detect and record various VOCs indicative of the presence of pathogens, which are associated with mortality and / or infection.

The invention relates to the technical field of surface protective coatings, in particular to a preparation method of a diffusion coating based on rare earth oxide modification, which comprises the steps of matrix pretreatment, permeation agent preparation and coating preparation. The permeation agent is composed of an aluminum supply agent, a filling agent, an activating agent and a permeation accelerating agent, wherein nano cerium oxide serves as the permeation accelerating agent and can remarkably improve the coating performance. By optimizing process parameters, the aluminizing temperature is reduced to 630 DEG C, and the time is shortened to be within 5 hours. The oxidation resistance, the hot corrosion resistance and the matrix bonding strength of the coating can be remarkably improved, and the coating is suitable for TiAl intermetallic compounds and other high-temperature alloy materials and has wide application prospects in the fields of aerospace and the like.