878 results about "Bismuth" patented technology

The invention discloses a high-bismuth slag and precious lead co-processing and efficient recycling method, and belongs to the technical field of non-ferrous metallurgy. High-bismuth slag and precious lead are mixed to obtain impurity-removed precious lead through impurity removal processes such as plug-blow antimony removal, liquation copper removal and tellurium removal by adding agents, and the impurity-removed precious lead is subjected to an oxidation refining process to obtain gold-silver alloy to recover precious metal. Bismuth and lead are similar, silver can be infinitely dissolved in a molten state, and the silver trapping agent has good silver trapping capacity. The high-bismuth slag and the precious lead are mixed to greatly reduce the temperature of a system, volatilization and unknown loss of metal such as Ag are reduced, energy consumption is remarkably reduced, the production cost is reduced, the recovery rate of metal such as bismuth, antimony and silver is increased, and the production efficiency is improved. The obtained molten slag is used for smelting high-bismuth slag, the obtained soot is used for smelting crude antimony, and efficient cyclic utilization of rare and precious metal resources is achieved.

The invention provides application of a silver-bismuth tungstate catalyst in preparation of methanol from light-driven CO2, and belongs to the technical field of CO2 conversion and reduction. Bismuth tungstate nanosheets, silver salt and water are mixed, the size of silver particles is controlled by adjusting the pH value, the silver-bismuth tungstate catalyst is obtained, and the size of the silver particles is 20-50 nm; silver is evenly distributed on the surface of bismuth tungstate, the obtained silver-bismuth tungstate catalyst is large in specific surface area and high in light response capacity, the silver-bismuth tungstate catalyst can generate a large number of high-energy hot electrons during illumination, in-situ photo-thermal conversion is achieved, no external heat source is needed for heat supply, the photo-thermal effect is enhanced, CO2 conversion is promoted, and the methanol yield is increased.

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 invention provides a lead-bismuth reactor nuclear sampler coating and a preparation method thereof.The preparation method comprises the steps that S3, according to the thickness of a CrAl coating, the bias voltage and target current of multi-arc ion plating equipment are adjusted, the bonding strength of the coating and a base body is optimized, and the target adhesive force reaches the scratch test critical load or above; s4, according to the bonding strength, the nitrogen flow and the air pressure are adjusted, a compact CrAl coating microstructure with the porosity lower than a porosity threshold value is generated, and the quality of the microstructure is detected and verified through a scanning electron microscope; s7, according to the thickness consistency, a screw rod or a pin shaft is selected as a base body part, a CrAl coating is deposited on the surface of the screw rod or the pin shaft to be matched with the sleeve cap, and the gap between the sleeve cap and the shaft part is controlled to be within a gap threshold value; and S10, according to hardness and wear resistance test results, the deposition time and bias voltage are adjusted, the performance of the CrAl coating and the performance of the TiN coating are optimized, and the requirements for long-term corrosion resistance and wear resistance in the lead-bismuth alloy environment are met. According to the invention, excellent performances of long-term corrosion resistance and wear resistance in a high-temperature lead-bismuth environment are realized, and the service life of parts is remarkably prolonged.

The invention provides a preparation method of a plate-shaped glassy carbon electrode, which comprises the following steps: curing a resin raw material into a plate-shaped resin block, carbonizing in an inert atmosphere, and respectively introducing a nitrogen source and a boron source for doping operation to obtain a co-doped plate-shaped resin block precursor; placing the co-doped plate-shaped resin block between two porous graphite plates, and carrying out high-temperature treatment to obtain a glassy carbon matrix; and immersing the glassy carbon substrate into the adhesion layer solution to form an adhesion layer, transferring the adhesion layer into a deposition solution which comprises a bismuth-containing solution and a gold-containing solution, forming bismuth-gold nano-dots on the adhesion layer, and washing and drying the bismuth-gold nano-dots to obtain the plate-shaped glassy carbon electrode. Through directional arrangement of crystal orientations, the tantalum carbide coating achieves higher electrical conductivity and thermal conductivity. And the sensitivity and the service life of the plate-shaped glassy carbon electrode are obviously improved and prolonged.

The invention belongs to the field of chemical engineering, and relates to a preparation method of a high-chroma bismuth vanadate pigment for a coating, which comprises the following steps: mixing a titanium-based ion sieve with an acidic vanadium leachate, filtering after the reaction is completed to obtain a first filtrate, adding mercaptoacetic acid into the first filtrate, and filtering after the reaction is completed to obtain a second filtrate; preparing a bismuth salt solution containing yttrium ions and zirconium ions, mixing the bismuth salt solution with the second filtrate, adjusting the pH value to be in linear gradient change from acidity to neutrality, heating to a first temperature at a set heating rate, aging, centrifuging and drying to obtain a precursor; and calcining the precursor at a second temperature to obtain the bismuth vanadate pigment. According to the method, the acid vanadium leaching solution is used as a raw material, and the bismuth vanadate pigment with high chromaticity and chemical stability is obtained while the production cost is reduced through an innovative ion sieve purification technology and lattice stabilization doping, so that the method has obvious economic benefits.

The invention relates to the technical field of welding materials, and particularly discloses a high-temperature-resistant flux-cored wire containing rare earth elements and a preparation method of the high-temperature-resistant flux-cored wire. The high-temperature-resistant flux-cored wire containing the rare earth elements comprises a welding wire skin and a flux core. The flux core comprises the following raw materials of dehydrated rutile, dehydrated potassium feldspar, zircon sand, metal chromium powder, metal nickel powder, electrolytic manganese, ferrotitanium, ferro-aluminum, potassium cryolite, potassium titanate, sodium titanate, fine iron powder, yttrium-based iron alloy powder, atomized ferrosilicon, nitrided ferrochrome, bismuth oxide, auxiliaries and the balance reduced iron powder. The auxiliary agent is a mixture of a zirconium-iron alloy, a titanium-iron alloy and an aluminum-magnesium alloy. A specific alloy auxiliary is introduced into the flux core to protect stable transition of rare earth yttrium, yttrium and multiple components synergistically optimize the weld joint performance, 253MA heat-resistant steel is matched, slag and electric arc regulation and control components and a reasonable process are matched, and the welding quality of the welding wire is improved.

The invention discloses a preparation method of a high-hydrophobicity liquid lead bismuth alloy nitride coating capable of increasing a high-temperature contact angle, which comprises the following steps of: pretreating a substrate, depositing a FeCrAl coating on the surface of the substrate by adopting magnetron sputtering, and nitriding the FeCrAl coating to obtain a nitride coating; the invention further discloses the high-hydrophobicity liquid lead bismuth alloy nitride coating for improving the high-temperature contact angle. According to the preparation method, the FeCrAl coating is nitrided, so that the surface strength and corrosion resistance of the FeCrAl coating are improved, the formed FeCrAl nitride layer with a compact structure has high lyophobicity on the liquid lead bismuth alloy, the material surface is in a non-wetting state all the time, the liquid lead bismuth alloy can be effectively prevented from permeating into an alloy matrix, and the service life of the material is prolonged. The material is suitable for being used as a cladding material of a lead-cooled fast neutron reactor.

The present application relates to a kind of methods and applications of growing bismuth-doped rare-earth iron garnet BRIG crystal by guided mode pulling-top seed crystal method.For solving the problems of large internal stress, many defects, difficult to prepare thick film of single crystal in the current liquid phase epitaxy method of growing BRIG crystal;And the problems of long growth cycle, difficult to obtain seed crystal in top seed crystal method, the present application combines the fast growth of guided mode pulling crystal and the high-quality single crystal growth of top seed crystal method, and invents guided mode pulling-top seed crystal method to realize the fast growth of high-quality BRIG single crystal.First, the large-size doped rare-earth iron garnet crystal with high lattice matching and similar composition is quickly grown by guided mode pulling method, which is cut into centimeter-level seed crystal, and high-quality BRIG bulk single crystal is quickly grown by TSSG method.The crystal grown by this method has the advantages of small internal stress, less cracking, good uniformity, fast crystal growth, etc., and has obvious advantages in high-performance magneto-optical isolator.

The invention relates to a method for preparing high-purity bismuth by removing impurity lead in refined bismuth through oxidation slagging, and belongs to the technical field of non-ferrous metals. Melting and oxidizing: melting a lead-containing refined bismuth raw material at 300-400 DEG C, adding bismuth oxide into the molten bismuth, and fully stirring to enable the bismuth oxide and lead to generate oxidation reaction to generate lead oxide; slagging reaction: adding boric anhydride (B2O3) into the melt, and enabling the boric anhydride (B2O3) to react with the generated lead oxide to generate lead borate slag; slag salvaging and lead removal: stirring for 30-60 minutes at the temperature of 300-400 DEG C in a heat preservation manner, so that the slagging reaction is fully carried out, generated lead borate slag with lower density floats to the surface of a melt, and a lead-containing slag phase is removed in a mechanical or manual slag salvaging manner; and after the slag salvaging process is finished, cooling the bismuth melt under a protective atmosphere until the bismuth melt is solidified to obtain a lead-removed high-purity bismuth product. According to the method, bismuth oxide and boric anhydride are introduced, metal lead is converted into lead borate slag easy to float, efficient and deep separation of lead and bismuth melt is achieved through the density difference, and the lead content can be reduced to 1 ppm or below.

The invention relates to a separation method suitable for At-211 produced by a linear accelerator, which comprises the following steps: performing gradient pressing on bismuth powder and a pore forming agent, and sintering on a porous silicon carbide substrate to form a gradient pore bismuth-silicon carbide composite target material; bombarding the gradient pore bismuth-silicon carbide composite target material through a high-energy particle beam generated by a linear accelerator, and carrying out nuclear reaction on bismuth atoms in the target material to generate At-211; the bombarded target material is pretreated through argon plasma; distilling the pretreated target material under pulse carrier gas to realize volatilization separation of At-211, wherein the carrier gas comprises inert gas, reducing gas and organic acid steam; the distilled gas is subjected to gradient condensation through the micro-channel condenser; and adding an extracting agent into the micro-channel condenser, and dissolving the At-211 in the extracting agent to obtain an At-211 solution. The high-flux separation method of At-211 suitable for linear accelerator production, provided by the invention, is stable, efficient and rapid.

The invention belongs to the field of oil and gas exploitation, geothermal exploitation and deep ground engineering, and discloses an oil and gas shaft crack plugging pressure repair material and method based on microwave heating bismuth-based alloy, the material comprises 74%-86% of bismuth-based alloy powder, 10%-15% of Fe3O4-SiO2 core-shell magnetic particles, 3%-8% of a microwave sensitizer and 1%-3% of a wetting agent. The repairing material is conveyed to the position, where shaft crack plugging repairing needs to be conducted, in the oil and gas shaft, then the repairing material is melted in a microwave heating mode, then the melted alloy is filled in shaft crack plugging, and then a rotating gradient magnetic field is used for repairing the oil and gas shaft crack. And the liquid alloy is driven to directionally migrate to a target crack area along the magnetic line, and after alloy liquid is cooled and solidified, pressure repairing of the oil and gas shaft crack plugging target position is achieved. Precise positioning, efficient filling, phase change control and complete recovery of the repairing material can be achieved in the extremely deep environment, and therefore the high-quality repairing requirement for oil and gas shaft crack plugging pressure repairing achieved through efficient liquefaction of plugging metal can be met.

The invention discloses a copper-based catalyst for catalyzing partial hydrogenation of nitrocyclohexane to prepare cyclohexanone-oxime as well as a preparation method and application of the copper-based catalyst. The catalyst comprises a main active component and an auxiliary active component, the main active component is copper, the auxiliary active component is selected from one or more of titanium, vanadium, chromium, molybdenum, zirconium, cadmium, indium, tin, antimony, niobium, silver, iron, zinc, magnesium, aluminum, bismuth, manganese, lanthanum, gold or lead, the total molar ratio of the copper to the auxiliary active component is (100-1): 1, and the catalyst is prepared by adopting a coprecipitation method or a supported impregnation-coprecipitation method. And the process is simple and green. Under mild conditions, the catalyst can realize the conversion rate gt of nitrocyclohexane; the selectivity of cyclohexanone-oxime is greater than or equal to 99%, and the method is obviously superior to the existing non-noble metal system, and is low in cost, good in stability and suitable for industrial production of green synthesis of caprolactam.

The invention relates to a lead-free and halogen-free soldering paste and a preparation process thereof, and belongs to the technical field of soldering paste production, through the combination of nano-silver-loaded carbon nanotubes, organically coated solder alloy powder and soldering flux, the surface tension of the lead-free and halogen-free soldering paste can be reduced by carbon nanotube surface carboxyl in the nano-silver-loaded carbon nanotubes, so that the lead-free and halogen-free soldering paste is obtained. Nano-silver and tin form an Ag3Sn strengthening phase which synergistically promotes wetting and spreading of the solder on a substrate, meanwhile, the carbon nanotubes loaded with the nano-silver are uniformly dispersed in the soldering paste to play a dispersion strengthening role, and the brittleness caused by bismuth segregation is effectively inhibited in cooperation with the grain refinement effect of copper and indium in the solder alloy powder; and the organic coating layer hydrogenated rosin-terpene resin and the soldering flux alcohol ether solvent form a slight dissolution-fusion effect, so that the welding flux alloy powder is prevented from being oxidized, an organic acid active agent can be released to remove a substrate oxidation film, the metallurgical bonding quality of a welding interface is further guaranteed, and the defects of pseudo soldering, cavities and the like are reduced.

The invention provides a method for preferentially extracting gold and silver from lead anode slime, and relates to the technical field of precious metal recovery, firstly, silver, antimony and other valuable metals in the lead anode slime are leached into a solution through catalytic oxidation leaching in the presence of a protective agent, and gold is enriched in residues; then, silver is selectively precipitated from the leachate, and silver precipitation residues and a valuable metal solution are obtained; and finally, valuable metals in the solution are recovered by adding a neutralizer and a precipitator, the obtained leaching mother liquor can be returned for leaching after being supplemented with hydrochloric acid, and the valuable metal precipitates are used for recovering antimony and bismuth. The method changes the traditional lead anode slime treatment thinking of first impurity removal and second refining, has the characteristics of high gold and silver direct recovery rate (greater than 99.5%), high reaction speed (total consumed time is less than 1 h), low cost and no generation of waste residue and wastewater, and is expected to solve the problems of long gold and silver recovery process, low direct recovery rate, capital overstock and difficult treatment of arsenic and antimony-containing smoke in the existing lead anode slime treatment method. The method has remarkable economic and environmental benefits and a good application prospect.

The application discloses a lead-based composite material and a preparation method thereof, a lead-acid battery composite current collector and a lead-acid battery, wherein the lead-based composite material comprises: a substrate; a conductive MXene layer arranged on the surface or part of the surface of the substrate; a metal modification layer arranged on the surface of the conductive MXene layer, wherein the metal type of the metal modification layer is selected from one or more of copper, nickel, silver, gold, platinum, magnesium, zinc, tin, chromium, antimony and bismuth; and a lead-based layer arranged on the surface of the metal modification layer. By jointly using the metal modification layer and the conductive MXene layer, the problem of poor composite bonding force between different substrate surfaces and the lead-based layer can be solved.

The invention discloses a preparation method of ultra-smooth low-expansion ceramic glaze for in-situ generation of cordierite, bismuth oxide and antimony oxide are introduced into a high-potassium low-sodium system to form a K-Mg-Sb-Bi multi-element eutectic system, so that the low thermal expansion property and the smooth property of the glaze are realized; in-situ precipitation of cordierite microcrystals in a glaze glass phase is more successfully guided, so that a ceramic glaze surface with excellent comprehensive performance is obtained.

The invention discloses an antimony electrolyte impurity removal adsorbent as well as a preparation method and application thereof, and relates to the technical field of antimony electrolyte purification. The adsorbent is specially used for solving the problem that lead and bismuth ions similar to antimony in potential in the antimony electrolyte are difficult to deeply remove. The preparation method comprises the following steps: mixing sulfuric acid, deionized water, antimony oxide powder and hydrogen peroxide according to a specific mass ratio (1: (0.8-1.5): (0.5-1.5)), and controlling the liquid-solid ratio to be 8-15 mL / g to form a synthetic initial solution; then reacting for 0.5-4 hours under the condition of stirring at the temperature of 60-90 DEG C and the speed of 200-600 r / min; and finally, carrying out solid-liquid separation and drying at 55-110 DEG C for 1-12 hours. When the adsorbent is applied, the adsorbent is added into electrolyte according to the proportion of 500-5000 times of the total mass of lead and bismuth, reaction is performed for 1-6 hours under the conditions of 30-90 DEG C and 200-550 r / min, and deep purification can be realized after standing, settling and separating. The method is short in technological process, mild in condition, easy to operate, environmentally friendly and high in lead and bismuth removal rate, purified liquid can return to an electrolysis system, the saturated adsorbent can be regenerated and reused, and good economic benefits and application prospects are achieved.

The invention provides high-stability double-layer core-shell coated pure copper silver-substituted conductive paste and a preparation method thereof, and belongs to the technical field of electronic special materials. The copper-resistant coating comprises the following components in percentage by mass: 82%-90% of antioxidant copper powder with a double-layer core-shell structure, 3%-6% of bismuth-boron-zinc lead-free low-melting-point glass powder, 3%-7% of a modified epoxy resin compound organic carrier, 2%-5% of a gradient volatilization compound solvent and 0.5%-2% of a special compound additive for copper. Through the double-layer core-shell copper powder design of inner-layer nano-silver passivation and outer-layer organic composite coating and in cooperation with a liquid-phase synergistic anti-oxidation system, the volume resistivity after slurry curing is smaller than or equal to 3.5 * 10 <-5 > omega.cm, the resistivity change rate after 1000-hour damp-heat aging at 85 DEG C / 85% RH is smaller than or equal to 10%, the normal-temperature storage period without opening a tank is larger than or equal to 6 months, direct curing can be conducted in the conventional air atmosphere of 120-160 DEG C, and the high-temperature-resistant copper paste can be applied to the field of high-temperature storage. The silver paste is completely compatible with production and application production lines of existing silver paste, equipment transformation is not needed, the comprehensive cost is reduced by more than 80% compared with pure silver paste, and the silver paste can be widely applied to the fields of PCBs, membrane switches, flexible electronics, photovoltaic back electrodes, LED packaging and the like.

The invention relates to the technical field of commercial spaceflight, in particular to a self-repairing liquid metal heat pipe for commercial spaceflight, which comprises a polyether-ether-ketone composite pipe, gallium bismuth zinc liquid gold, a micro-nano repairing film, a main hot runner, a pressure detector, a standby hot runner and an emergency plugging valve, and the main hot runner is an axial through channel in the polyether-ether-ketone composite pipe, and the standby hot runners are annularly and circumferentially arrayed along the inner wall of the main hot runner. Compared with heat conduction in the prior art, medium leakage is stopped through cooperative plugging in a damaged scene, so that the heat conduction efficiency is improved, and the service life of the heat exchanger is prolonged. And meanwhile, the detector is in signal linkage with the plugging valve, a heat transfer loop is rapidly switched in the case of serious damage, the continuous and stable thermal control function is achieved, and therefore the on-orbit operation life of a spacecraft is further prolonged.

The invention belongs to the technical field of non-ferrous smelting, and particularly relates to a method for leaching copper from silver separation furnace slag and application. The method for leaching the copper from the silver separation slag comprises the following steps: (1) mixing and slurrying the silver separation slag and water, then adding concentrated sulfuric acid to carry out a leaching reaction, controlling the final pH value to be 1-4.5, and introducing hydrogen peroxide during the leaching reaction to obtain a leaching solution and leaching slag; (2) mixing the leached residues with concentrated sulfuric acid, curing, leaching, and filtering to obtain cured liquid and cured residues; the cured liquid is subjected to countercurrent circulation back to the step (1) to replace water and concentrated sulfuric acid. Most of copper is leached from the silver separation furnace slag through first-stage concentrated sulfuric acid oxidation leaching, so that the copper is separated from metals such as lead, bismuth, antimony and silver; and meanwhile, a second-stage curing reaction is introduced, the structure in the leaching slag is destroyed by concentrated sulfuric acid, copper and oxides thereof in a complex structure are released, the copper content in the cured slag is smaller than 0.1%, the copper leaching rate reaches 99% or above, and deep recovery of copper in the silver separation slag is achieved.

The invention relates to the technical field of sintered permanent magnets for motors, in particular to a high-density anisotropic manganese-bismuth sintered permanent magnet for a motor and a preparation method of the high-density anisotropic manganese-bismuth sintered permanent magnet. By combining vacuum rapid hardening for preparing uniform sheets, two-stage long-time heat treatment for optimizing the LTP-MnBi phase content, magnetic field orientation and isostatic pressing forming and a key two-stage low-temperature sintering process, high densification and grain orientation of the magnet are successfully realized under the condition far lower than the LTP-MnBi phase decomposition temperature. The technical problem that high densification of a block magnet is difficult to realize on the premise of avoiding LTP-MnBi phase decomposition in the prior art is solved, so that the manganese-bismuth sintered permanent magnet with high density, high coercive force and good anisotropy is prepared, and a foundation is laid for application of the manganese-bismuth sintered permanent magnet in a high-temperature motor.

The invention belongs to the technical field of all-vanadium redox flow battery electrodes, and particularly relates to a bismuth metal modified electrode, a preparation method, application and an all-vanadium redox flow battery. The preparation method comprises the following steps: dissolving a bismuth source in an organic solvent to prepare an impregnation liquid; soaking the polyacrylonitrile-based graphite felt in the impregnation liquid, taking out the polyacrylonitrile-based graphite felt, and drying the polyacrylonitrile-based graphite felt to obtain a bismuth-source-impregnated polyacrylonitrile-based graphite felt; and performing Joule thermal pulse discharge heating on the polyacrylonitrile-based graphite felt impregnated with the bismuth source, washing and drying to obtain the bismuth metal modified electrode. The voltage of Joule thermal pulse discharge heating is 24-36 V, and the current is 56-83 A. According to the preparation method, joule thermal equipment is adopted for pulse calcination, bismuth metal particles are generated on the surface of the polyacrylonitrile-based graphite felt in situ, and the problem that the metal particles are prone to agglomeration is solved. Meanwhile, when the bismuth source is bismuth nitrate, nitrogen doping is synchronously realized while active sites of bismuth metal particles are introduced, so that the hydrophilicity and the reaction activity of the polyacrylonitrile-based graphite felt electrode are improved.

The application is suitable for the field of nuclear reactor technology and discloses a filtering device and filtering method for a lead-bismuth cooled pool type reactor, which comprises a fixing assembly, a branch pipeline and a filtering assembly; the fixing assembly is arranged on the side of the main channel, and the fixing assembly comprises the branch pipeline in which the filtering assembly is detachably installed; the branch pipeline is connected with the side of the main channel through the fixing assembly to form the branch pipeline, and the filtering assembly is used for filtering and purifying in the branch pipeline without providing filtering power by itself; the filtering device as a whole can be arranged in the pool type reactor to ensure the integrity of the boundary of the reactor body; the filtering assembly has a simple structure and is convenient to install and replace, and can be operated in the reactor for a long time, so that the filtering device has a long service life and the replacement period of the filtering device is reduced.

The invention discloses a multi-band high-stability ferrite magnetic material composite formula and a preparation process, and relates to the technical field of magnetic materials. The ferrite magnetic material composite formula comprises 38-42 parts of ferric oxide powder, 37-41 parts of ferroferric oxide powder, 6-12 parts of graphene nanosheets, 5-7 parts of hydroxypropyl methyl cellulose, 6-9 parts of lanthanum oxide, 4-6 parts of scandium oxide, 1-3 parts of nano titanium dioxide, 4-6 parts of bismuth magnesium boron, 9-13 parts of ferric sulfate, 3-5 parts of manganese sulfate, 4-6 parts of zinc sulfate, 2-4 parts of copper sulfate and 2-3 parts of samarium sulfate. By utilizing a physical vapor deposition gradient doping process, the problems that an existing ferrite magnetic material is single in electromagnetic performance, cannot stably and efficiently work in a multi-frequency-band complex electromagnetic environment and cannot meet the requirements of the fields of communication, radar, electronic countermeasure and the like for wide-frequency-band and high-performance magnetic materials can be solved.

This invention belongs to the field of nanomaterial preparation technology and discloses a highly stable bismuth-based core-shell heterojunction nanomaterial (Bi@Bi2X3) and its preparation method. The method uses a non-aqueous composite electrolyte as a medium to construct an electrochemical system to achieve simultaneous exfoliation and in-situ coating of the material. Powdered Bi@Bi2X3 nanomaterials are precisely synthesized through separation and washing, chemical reduction enhancement, and freeze-drying processes. The process described in this invention is not only simplified and has mild reaction conditions, but also possesses excellent large-scale preparation capabilities. More importantly, the resulting heterojunction material, through its unique core-shell structure design, effectively overcomes the easy oxidation defect of traditional bismuth-based materials, exhibiting excellent air stability.

The application discloses alloy solder and a preparation method thereof, and relates to the technical field of welding. The alloy solder prepared by the application is a tin-based alloy solder, which comprises tin, silver, copper, nickel, cerium, nitrogen-doped cerium oxide, bismuth and erbium. The melting point of bismuth is relatively low, which can reduce the eutectic temperature of the alloy, so that the alloy solder can be used for low-temperature welding. However, the wettability of the solder is reduced. Therefore, a small amount of cerium is added at the same time when the bismuth is added. Under the synergistic effect of the cerium, the bismuth and the erbium, the wettability is improved, and the alloy solder is refined. A small amount of nitrogen-doped cerium oxide is further added, which can inhibit the growth of alloy eutectic compounds in the alloy solder in the non-homogeneous nucleation center, so that the cerium, the bismuth and the erbium in the solder can play the maximum role. In addition, the solder is rapidly cooled during the cooling and solidification of the solder, so that the size of each dendrite in the alloy is reduced. When the high-melting-point nitrogen-doped cerium oxide is uniformly dispersed in the solder, the crystal phase structure of the multi-component alloy solder is uniform, and the crystal grains are more refined.

The invention discloses a preparation method and application of a heterojunction catalyst based on a two-dimensional zinc porphyrin metal organic framework, and belongs to the field of photochemical energy conversion and photocatalytic degradation. The invention aims to solve the technical problems of high-quality preparation of the artificial photosynthetic photocatalytic composite material and how to effectively improve the photochemical energy conversion efficiency. The method comprises the following steps: 1, dissolving bismuth nitrate pentahydrate, sodium tungstate dihydrate and sodium dodecyl dimethyl benzene sulfonate in deionized water, fully stirring, and transferring the solution to a reaction kettle for hydrothermal reaction; cooling to room temperature, washing and drying to obtain bismuth tungstate solid powder; 2, adding bismuth tungstate and meso-tetra (4-carboxyl phenyl) porphin into a mixed solution of N, N-dimethylformamide and ethanol, carrying out ultrasonic treatment, and fully stirring to obtain a solution A; dissolving zinc nitrate hexahydrate, pyrazine and polyvinylpyrrolidone in a mixed solution of N, N-dimethylformamide and ethanol, and fully stirring to obtain a solution B; after the solution is fully dissolved, dropwise adding the solution B into the solution A under ultrasonic and stirring conditions, and then putting the beaker into an oil bath pan for heating; and cooling to room temperature, washing, and storing in an ethanol solution to obtain the Zn-MOF / Bi2WO6 heterojunction composite material.

The invention discloses high-endurance-strength high-silicon martensite heat-resistant steel for a lead-bismuth reactor and a preparation method of the high-endurance-strength high-silicon martensite heat-resistant steel, and belongs to the technical field of corrosion-resistant and heat- The heat-resistant steel comprises C, Si, Cr, Ni, Mo, W, Mn, V, Nb and N, the Mo equivalent is 0.8-1.2, the CNB is smaller than 14, and the balance is Fe and inevitable impurities. The formation of a compact SiO2 protective film is promoted by increasing the content of Si, and meanwhile, Mo and W are adopted for synergistic solution strengthening and are matched with N, V and Nb to form a dispersed MX precipitated phase. The heat-resistant steel is prepared through the processes of smelting, homogenizing, forging, hot rolling, normalizing and tempering, and a full-martensite structure can be obtained. And the obtained material has good liquid lead and bismuth corrosion resistance, room-temperature and high-temperature mechanical properties and relatively high high-temperature endurance strength, and is suitable for structural materials serving in high-temperature liquid lead and bismuth environments such as a lead-cooled fast reactor and the like.

The invention relates to the technical field of electrodes for vanadium batteries, in particular to a preparation method of a catalytically active electrode for a vanadium battery, the catalytically active electrode and application of the catalytically active electrode. The preparation method comprises the following steps: loading a bismuth oxide water-phase dispersion liquid as a precursor on the surface of a graphite felt electrode substrate, placing the graphite felt electrode in an inert atmosphere to carry out a carbon thermal reduction reaction, and carrying out a solid-phase reaction on bismuth oxide and the graphite felt carbon substrate in the inert atmosphere to generate a strongly combined catalytic active site in situ. By pertinently controlling the concentration of the bismuth oxide water-phase dispersion liquid and the temperature of the carbon thermal reduction reaction, active components in the prepared catalytic active electrode for the vanadium battery are uniformly and firmly combined on the surface of a matrix, and high uniformity and high stability are shown. And meanwhile, a loading-first and one-step carbon thermal reduction method is adopted, so that large-scale production can be realized, the electrochemical activity of the product is effectively improved, the uniformity and consistency of the performance can be realized, and the multi-dimensional strict requirements of commercial production on the electrode performance and the manufacturing efficiency are effectively met.