386 results about "Oxygen atmosphere" patented technology

The invention relates to the technical field of electro-catalysis oxygen evolution, and particularly discloses a nickel-molybdenum foam composite oxygen evolution electro-catalysis material with high-valence nickel induced by molybdate radicals and a preparation method of the nickel-molybdenum foam composite oxygen evolution electro-catalysis material aiming at the problem that an existing oxygen evolution electro-catalysis material is insufficient in comprehensive performance or poor in performance stability. Soaking in a NaCl aqueous solution, and taking out; s2, mixing the nickel-molybdenum alloy foam with a K3 [Fe (CN) 6] aqueous solution, heating, and carrying out a hydrothermal reaction; and S3, finally, the nickel-molybdenum alloy foam is placed in the air or oxygen atmosphere and heated to 350-450 DEG C, heat preservation treatment is conducted for 2 h, and the nickel-molybdenum foam composite oxygen evolution electro-catalysis material is obtained. Molybdate anions are adopted as a sustainable induction source to be coupled with a NixOy / Fe3O4 heterogeneous interface, integrated construction is achieved on a nickel-molybdenum foam framework, and the nickel-molybdenum foam composite material has the advantages of being low in overpotential, high in stability, high in activity, high in binding force and long-term in durability and meanwhile being simple in process, easy to amplify on a large scale and the like.

The invention relates to a method for recycling polyethylene plastic through catalytic oxidation cracking, and belongs to the technical field of plastic recycling. The method comprises the following steps: mixing a Co / Al2O3 catalyst, polyethylene plastic and water, and carrying out a catalytic reaction in an oxygen-containing atmosphere at a set temperature, so that the polyethylene plastic is converted into binary acid, thereby obtaining a reaction solution. The low-price Co / Al2O3 catalyst is applied to catalytic oxidation cracking of the polyethylene plastic, the polyethylene plastic is converted into the binary acid, the yield of the binary acid is stabilized at 70% or above and reaches 115% at most, and the Co / Al2O3 catalyst is low in price and low in cost. The low-cost and low-energy-consumption improvement of the yield of the binary acid converted from the polyethylene plastic through catalytic oxidation cracking is fully realized, and a new way is provided for the high-value conversion of the polyethylene plastic.

The invention provides sintering flue gas denitration activated carbon and a preparation method thereof.The preparation method comprises the steps that coal-based activated carbon raw material powder and an aqueous solution of a nitrogen-containing compound and a phosphorus-containing compound are evenly mixed, impregnated and dried, and a nitrogen-phosphorus co-doped precursor is obtained; blending the catalytic components to obtain raw material strips; primarily forming pores, and activating for the first time in a water vapor atmosphere; carrying out secondary loading and pore regulation, and carrying out secondary activation to obtain a secondary carbon body; and carrying out heat treatment on the secondary carbon body in an oxygen-containing atmosphere to convert the loaded metal precursor into a metal oxide. According to the invention, through a cascade catalytic network constructed by nitrogen and phosphorus doping and titanium, tungsten and vanadium oxides and an optimized pore channel formed by step-by-step activation of water vapor and carbon dioxide, the denitration efficiency of the catalyst breaks through 80% and is far higher than that of common activated carbon. The sintering flue gas denitration system has high activity and high stability, can greatly reduce the series number of denitration towers, obviously reduces the system resistance and operation energy consumption, and provides an efficient scheme for solving the problems of low sintering flue gas denitration efficiency and high cost.

The invention belongs to the technical field of preparation of soft magnetic composite materials, and particularly relates to an insulation coating method and application of a soft magnetic powder material. The insulating coating method comprises the following steps: (1) uniformly mixing low-melting-point metal or alloy powder with silica sol, a silane coupling agent and a thermocuring resin glue solution to obtain coating slurry; and (2) uniformly mixing soft magnetic powder with the coating slurry obtained in the step (1), firstly performing hot-pressing curing molding at the temperature of 60-100 DEG C under a vacuum condition, and then performing hot-pressing sintering treatment at the temperature higher than the melting point temperature of low-melting-point metal or alloy powder and under an oxygen-containing atmosphere condition to obtain the insulated and coated soft magnetic powder material. According to the insulating coating method, the advantages of an organic material insulating coating method and an inorganic material insulating coating method are combined, the defects of the organic material insulating coating method and the inorganic material insulating coating method are overcome, and the stability and the insulating coating effect of the insulating coating layer are remarkably improved.

The invention discloses a non-noble metal ORR catalyst and a preparation method thereof, and belongs to the technical field of electro-catalysis. The method comprises the following steps: (1) adding 5, 10, 15, 20-tetra (4-cyanophenyl) porphyrin and nickel salt into an organic solvent, and synthesizing a supramolecular crystal precursor UPC-S7 through solvothermal reaction; (2) carbonizing the supramolecular crystal precursor UPC-S7 in an inert atmosphere to obtain a Ni-coated NC material; (3) oxidizing the Ni-coated NC material in an oxygen-containing atmosphere to obtain a Ni / NiO-coated NC material; and (4) sequentially soaking and etching the Ni / NiO-coated NC material by using a nitric acid solution and an ammonia water solution, and then washing and drying to obtain the non-noble metal ORR catalyst. The prepared catalyst does not contain precious metal such as platinum, the raw material cost is remarkably reduced on the basis of ensuring the ORR activity and stability of the catalyst, and a new scheme is provided for solving the cost bottleneck of a fuel cell.

The invention provides a method for co-processing multi-source copper-based waste through copper concentrate, and relates to the field of metal smelting. The copper concentrate and the copper-based waste are subjected to first mixing, and a mixture is obtained; under the oxygen-containing atmosphere, the mixture is smelted, and matte and smelting slag are obtained; the matte and the silicon-based slag former are subjected to first blowing to obtain first blowing slag; carrying out second mixing on the first converting slag and a reducing agent, and carrying out second converting to obtain crude copper; the copper concentrates comprise copper sulfide concentrates and copper oxide concentrates. Copper concentrate matte smelting and copper-based waste pyrogenic smelting are combined together, the problems that the copper-based waste smelting scale is small, and furnace burning is caused by overburning are solved, and the problem that a slag former is additionally added in copper concentrate matte smelting is solved. Through collaborative smelting, valuable metals such as copper, gold and silver enter matte, iron, aluminum and silicon in the copper-based waste enter smelting slag, and a silicon-based slag former and a reducing agent are added when the matte is blown, so that the slagging function is realized, and the valuable metals in the waste are recovered.

The invention relates to the technical field of sodium ion battery negative electrode materials, in particular to a method for preparing hard carbon from medium-temperature coal tar-based pitch, which comprises the following steps: (S1) hydrogenating the medium-temperature coal tar-based pitch and a hydrogen donor solvent at high temperature and high pressure to obtain hydrogenated pitch; (S2) mixing the hydrogenated asphalt with a Lewis acid catalyst, and oxidizing in an oxygen-containing atmosphere to obtain first oxidized asphalt; (S3) uniformly mixing the first oxidized asphalt and a modifier, and carrying out secondary oxidation crosslinking to obtain second oxidized asphalt; and (S4) uniformly mixing the second oxidized asphalt and a pore-forming agent, and carrying out heat treatment in an inert atmosphere to obtain the product hard carbon material. The hard carbon material prepared by the method disclosed by the invention is benefited from a specific preparation process, shows relatively high specific capacity and first coulombic efficiency, and also has excellent rate capability. The preparation method is simple, low in cost and easy for large-scale production, and lays a foundation for large-scale production of the sodium-ion battery negative electrode material.

The invention provides high-purity superfine titanium diboride and a preparation method thereof, and relates to the field of titanium diboride preparation. The method comprises the following steps: mixing boron oxide, titanium hydride, a carbon source, nano rare earth oxide and an organic solvent, and drying to obtain a mixture; in a vacuum environment, performing first roasting on the mixture to obtain a first roasted material; and in an oxygen-containing atmosphere, carrying out second roasting on the first roasting material to obtain the high-purity superfine titanium diboride. In the first roasting process, boron oxide, titanium hydride and a carbon source are completely melted and fully contacted, then further, the carbon source forms a carbon skeleton, the contact area between the melted boron oxide and titanium hydride and the carbon skeleton is further enlarged, liquid-liquid mixing and the increase of the contact area can reduce the reaction kinetic conditions, the reaction temperature is greatly reduced, and the reaction time is greatly shortened. The particle size of the generated titanium diboride is reduced, and the molten boron oxide and titanium hydride react on the porous carbon skeleton in a liquid-liquid form to generate the high-purity superfine titanium diboride.

The invention belongs to the technical field of third-generation semiconductor material defect control. According to the method for eliminating the silicon carbide small stacking fault based on high-temperature oxidation, a silicon carbide substrate is scanned and represented in a photoluminescence mode, and the target small stacking fault is accurately recognized and positioned; cleaning the substrate to remove surface impurities, performing high-temperature oxidation treatment in a dry oxygen atmosphere, and growing an oxide layer under control; constructing a composite interface stress field at an interface by utilizing thermal expansion coefficient mismatch and reaction molar volume expansion between the oxide layer and the substrate, and driving target stacking fault atom arrangement to generate directional reconstruction, so that the target stacking fault atom arrangement is converted into a matrix standard sequence; and finally, nitric oxide auxiliary annealing is carried out, and the reconstructed lattice configuration is solidified by utilizing a nitrogen passivation effect. The method is simple in process and high in compatibility, small stacking fault can be efficiently and stably eliminated, the silicon carbide substrate crystal quality is remarkably improved, and a guarantee is provided for preparation of a high-reliability power device.

The invention provides a volume photocuring three-dimensional printing method and device based on oxygen permeation interface dynamic oxygen inhibition control, and relates to the technical field of photocuring additive manufacturing. The volume photocuring three-dimensional printing method comprises the following steps that a resin cavity is prepared, the closed container is formed by compounding an oxygen permeable membrane and a transparent rigid material; establishing an oxygen inhibition layer: maintaining air or oxygen-containing atmosphere outside the closed container, so that oxygen continuously permeates into a resin boundary area through the oxygen permeation membrane to form the stable oxygen inhibition layer; volume light field projection: projecting a projection image generated by a computed tomography algorithm into the resin volume by adopting a calculation axial photoetching type multi-angle projection mode to realize multi-angle rotary projection exposure; edge curing is delayed through the boundary oxygen inhibition layer, the problem that the boundary light dosage of traditional volume printing is not uniform is solved, the final forming volume is enlarged by 1.5-3 times compared with the prior art, and the size bottleneck of volume light curing printing is effectively solved.

The invention belongs to the technical field of battery materials, and particularly relates to an asphalt-based hard carbon precursor, a hard carbon material and a preparation method and application of the asphalt-based hard carbon precursor and the hard carbon material. According to the method, protonic acid or lewis acid of a specific type and dosage is used as a catalyst to be mixed with the asphalt powder, and the reaction is carried out in an oxygen-containing atmosphere at a proper temperature, so that the synergistic promotion of oxidation and cross-linking is realized, the cross-linking activation energy of oxygen-containing functional groups is remarkably reduced, oxygen-containing active sites generated by asphalt oxidation are quickly and fully utilized, and the service life of the asphalt is prolonged. Therefore, the precursor with high oxygen content, stable cross-linked structure and good thermal stability is obtained. After the precursor is carbonized, the pitch-based hard carbon material with excellent electrochemical performance can be prepared, and the pitch-based hard carbon material is suitable for being used as a battery negative electrode material.

The present invention relates to the technical field of waste catalyst treatment, and discloses a waste hydrogenation catalyst treatment method, a hydrogenation catalyst, and a heavy oil and / or residual oil hydrotreatment method, the method comprises: (1) in an oxygen-containing atmosphere, carrying out carbon burning treatment on the waste hydrogenation catalyst; (2) leaching part of metal in the catalyst obtained in the step (1) by adopting an acid solution to obtain a leaching solution and a leaching residual catalyst; wherein compared with the waste hydrogenation catalyst, the leaching rate of vanadium in the leaching residual catalyst in terms of oxide is 62-94%; (3) carrying out extraction treatment on the leaching solution to obtain an extraction solution containing V < 4 + > and a raffinate; and (4) dipping the leaching residual catalyst obtained in the step (2) by adopting the raffinate, and then carrying out high-temperature activation treatment at 600-800 DEG C. The hydrogenation catalyst obtained by the treatment method is applied to the hydrotreating process of heavy oil and / or residual oil, and has relatively good demetallization performance and relatively high desulfurization activity stability.

The invention discloses a vertical sintering method for improving EuBCO high-temperature superconducting target material component uniformity, and belongs to the field of superconducting target material preparation. The cylindrical EuBCO target blank is vertically fixed to the center of an alumina crucible, the axis of the cylindrical EuBCO target blank is made to be perpendicular to the bottom face of the crucible, and sintering is conducted in the oxygen atmosphere at the temperature of 900-950 DEG C. Traditional surface contact is replaced by point / line contact, the contact area is reduced by more than or equal to 80%, and the gas diffusion retardation effect of the contact surface is eliminated; meanwhile, oxygen permeation and CO2 diffusion are enhanced through the exposed side faces, and generation of impure phases such as BaCO3 and BaCuO2 is inhibited. The XRD contact ratio of the two end faces of the sintered target material is larger than 99%, and the problem of composition segregation caused by traditional horizontal sintering is solved. The method does not need a crucible coating or an isolating layer, and is low in cost and free of secondary pollution.

The invention relates to the technical field of hard carbon material manufacturing, in particular to a method for preparing a hard carbon negative electrode material from medium and low temperature coal tar based pitch, which comprises the following steps: (S1) uniformly mixing the medium and low temperature coal tar based pitch and a cross-linking modifier, and carrying out heat treatment to obtain cross-linked modified pitch; the cross-linking modifier is a compound of a copolymer and a compound A; (S2) mixing the cross-linked modified asphalt with sulfur-containing polyaldehyde, and oxidizing in an oxygen-containing atmosphere to obtain first oxidized asphalt; (S3) uniformly mixing the first oxidized asphalt and a modifier, and carrying out secondary oxidation crosslinking to obtain second oxidized asphalt; and (S4) uniformly mixing the second oxidized asphalt and a pore-forming agent, and carrying out heat treatment in an inert atmosphere to obtain the product hard carbon material. The hard carbon material prepared by the invention has excellent electrochemical performance, is suitable for a negative electrode material of a sodium-ion battery, and remarkably improves the first effect and cycling stability.

The invention discloses a method for preparing YAG transparent ceramic by two-step sintering, which comprises the following steps: 1) weighing yttrium oxide powder and aluminum oxide powder according to a stoichiometric ratio, mixing, and carrying out solid-phase reaction to synthesize YAG powder; 2) performing dry grinding and wet grinding on the obtained YAG powder to obtain mixed slurry; 3) drying the obtained mixed slurry to obtain powder, and performing compression molding and cold isostatic pressing to obtain a ceramic biscuit; and 4) pre-sintering the obtained ceramic biscuit in an oxygen-containing atmosphere, embedding the pre-sintered ceramic with oxide particles, and carrying out hot isostatic pressing sintering to prepare the YAG transparent ceramic. On the basis of obtaining the YAG transparent ceramic with high optical quality, a microstructure with a fine grain size can be obtained, and good mechanical properties are considered; the preparation method is simple, the equipment cost and energy consumption are low, the traditional annealing step can be omitted, and a new thought can be provided for preparation of the high-performance YAG transparent ceramic.

The invention provides a method for removing phosphorus from a cobalt sulfate solution. The method comprises the following steps: providing a cobaltous sulfate solution to be treated; the method comprises the following steps: mixing a to-be-treated cobaltous sulfate solution, a composite polymer soluble ferric salt and a coagulant aid, carrying out precipitation reaction, and separating to obtain phosphorus-containing slag and cobaltous sulfate primary purified liquid; a deep phosphorus removal adsorbent is adopted to adsorb trace phosphorus in the cobalt sulfate primary purification liquid, then trace iron in the cobalt sulfate primary purification liquid generates precipitates in an oxygen-containing atmosphere, and after separation, a cobalt sulfate secondary purification liquid is obtained. According to the method, firstly, the synergistic effect of the composite polymer soluble ferric salt and the coagulant aid is adopted, and primary efficient removal of phosphorus is achieved; then, a deep phosphorus removal adsorbent is used for directionally adsorbing trace phosphorus in the cobalt sulfate primary purification liquid, so that deep removal of phosphorus is further realized; and finally, the residual trace iron is precipitated and separated in the oxygen-containing atmosphere, so that the purity of the secondary purified cobalt sulfate liquid is further guaranteed.

The invention provides a process method for producing ferrotitanium powder by reducing ilmenite, which comprises the following steps of: uniformly mixing ilmenite concentrate with a biomass-coal mixed reducing agent, a nanoscale additive and the like, reducing in a rotary kiln under a temperature-controlled and oxygen-controlled atmosphere, quenching and cooling a product by water, and performing multi-stage ore grinding magnetic separation to obtain metal iron particles and a titanium-rich material; and preparing the two into a ferrotitanium powder product. The process integrates innovative units of raw material homogenization pretreatment, biomass-coal mixed reducing agent dynamic proportioning, LIBS + Raman spectrum on-line monitoring closed-loop control, nano CaO-Na2O composite catalyst buffer addition, finished product multistage magnetic separation reforming and the like. The product composition fluctuation is obviously reduced, the TiO2 content fluctuation is controlled within + / -0.4%, the FeO content fluctuation is controlled within + / -0.5%, the metallization ratio is improved to 90% or above, the heat efficiency is improved by about 20%, and the energy consumption per unit yield is reduced by about 15%. The ilmenite is directly, efficiently and cleanly utilized, a high-quality titanium-rich raw material can be provided for production of titanium dioxide, titanium sponge and the like, meanwhile, the byproduct high-grade iron powder is used for steelmaking, and the comprehensive utilization benefit of resources is remarkable.

This invention discloses a method for preparing high rare-earth-doped low-loss boron-containing glass optical fibers. The steps are as follows: weigh glass raw materials containing rare-earth oxides and boron oxide, mix them uniformly, and place them in a high-temperature furnace. First, heat the mixture under a high-purity nitrogen atmosphere, then switch to a high-purity oxygen atmosphere or a high-purity air atmosphere for continued heating. The resulting glass melt is cooled and annealed to obtain a large glass block. The glass is then processed into a preform and placed in an optical fiber drawing furnace for fiber drawing under a high-purity oxygen atmosphere, thus achieving the preparation of high rare-earth-doped low-loss glass optical fibers. This invention eliminates the additional glass matrix absorption in the near-infrared region caused by boron in boron-containing glass optical fibers and also transforms the transition metal impurity ions from a low valence state with broad absorption in the near-infrared region to a high valence state with narrow low absorption in the near-infrared region. Both of these aspects significantly reduce the matrix absorption of boron-containing glass optical fibers, providing possibilities for the application of high rare-earth-doped low-loss glass optical fibers.

This invention belongs to the field of semiconductor optoelectronic device manufacturing technology and discloses a multi-stage annealing process for ITO thin films, including the following steps: Step 1: Under high vacuum protection, the furnace temperature is raised from room temperature to a first temperature T1 and held for a first time; Step 2: The furnace temperature is raised to a higher second temperature T2 and held for a second time, without the need for oxygen introduction during the second holding stage; Step 3: While maintaining the second temperature T2, a third holding stage is performed, and oxygen is introduced during the third holding stage; Step 4: A controllable cooling process is performed, which includes at least a slow cooling stage under the oxygen atmosphere and a rapid cooling stage under an inert gas or extremely low oxygen concentration atmosphere. This invention achieves precise staged control of the ITO thin film crystallization process, oxygen vacancy filling, and interfacial reactions by precisely controlling the oxygen partial pressure and cooling rate at different temperature stages.

The application discloses a treatment method for reducing carbon content of REBCO powder, and relates to the technical field of superconducting material preparation. The treatment method is that the REBCO powder is placed in an ozone-containing atmosphere for heat treatment. The core principle of the treatment method is that the strong oxidizing property of ozone and active oxygen atoms generated by the decomposition of ozone are used to directly oxidize carbon impurities in the REBCO powder into CO2 gas at a lower temperature, and meanwhile, the superconducting phase is avoided from being damaged. It is verified by a carbon analyzer that the carbon reduction efficiency of the powder after ozone heat treatment is several times higher than that of the powder after traditional oxygen atmosphere treatment.

The invention belongs to the field of sewage treatment, and particularly relates to a tencel production wastewater treatment process. Comprising the following steps: etching a carbon nanotube to obtain a porous carbon nanotube; carrying out amino functional modification on the porous carbon nanotube to obtain a modified carbon nanotube; loading cobaltosic oxide on the modified carbon nanotube, and then forming a nickel-cobalt composite oxide on the outer wall of the modified activated carbon by adopting nickel salt to obtain the catalyst, the method comprises the following steps: adding a catalyst into wastewater, heating a system to 70-90 DEG C, then stopping heating, and carrying out an illumination reaction in an oxygen-containing atmosphere; according to the process, through the synergistic effect of light, heat and oxygen, the reaction activity of active sites on the surface of the catalyst is enhanced, the reaction time is shortened, meanwhile, the interaction between amino and reactants is enhanced, and desorption and degradation of pollutants are accelerated.

The invention provides a photocatalytic method for degrading polystyrene into benzoic acid, which comprises the following steps: dissolving polystyrene in a mixed solvent containing acetonitrile and chlorobenzene, adding a catalyst FPQL-OMe and iron trifluoromethanesulfonate, and reacting under the conditions of oxygen atmosphere and illumination to generate benzoic acid, wherein the FPQL-OMe and the iron trifluoromethanesulfonate are synergistically used as a photocatalyst. The invention provides a method for photocatalytic degradation of polystyrene, which is mild in condition, rapid, efficient and high in selectivity, and particularly provides a photocatalytic method for degrading and converting polystyrene into benzoic acid at a relatively high yield.

The invention discloses a sintering method of a stainless steel fiber felt. The method specifically comprises the following steps: S1, stacking at least one stainless steel fiber to form a stainless steel fiber felt blank with a gradient composite structure; s2, the stainless steel fiber felt blank is placed in an oxygen-containing atmosphere to be subjected to pre-oxidation treatment, and a stainless steel fiber felt blank loaded with a Cr2O3 / Fe2O3 composite oxide layer is obtained; and S3, the stainless steel fiber felt blank loaded with the Cr2O3 / Fe2O3 composite oxide layer is subjected to reduction sintering treatment, and the stainless steel fiber felt is obtained. The stainless steel metal fiber felt is sintered through an oxidation-reduction two-step method, the tensile strength and elongation of the stainless steel metal fiber felt can be improved, and the industrial problems that the low-temperature sintering binding force of superfine fibers (the diameter is smaller than 2 micrometers) is poor, the high-temperature sintering neck is abnormally large, and an effective binding interface is difficult to form can be solved.

The invention provides a precursor containing primary particles distributed in the radial direction and a preparation method and application thereof.The preparation method comprises the steps that a mixed metal source solution, a complexing agent solution and a precipitator solution are subjected to a first coprecipitation reaction, and a core is obtained; in oxygen-free protective gas, increasing the flow of the mixed metal source solution, the complexing agent solution and the precipitator solution, and carrying out second coprecipitation reaction to obtain a core coated with a compact layer; in an oxygen-containing atmosphere, introducing the mixed metal source solution, the complexing agent solution, the precipitator solution and the doped metal source solution, and carrying out a third co-precipitation reaction to obtain a precursor; the pH and complexing agent concentration of the third co-precipitation reaction are smaller than those of the second co-precipitation reaction and are smaller than those of the first co-precipitation reaction. According to the preparation method, the precursor comprises the primary particles distributed along the radial direction by regulating and controlling the conditions of the coprecipitation reaction at each stage, so that the performances such as circulation and rate of the positive electrode material are improved.

The application belongs to the technical field of soft magnetic composite material preparation, and particularly relates to an insulation coating method for soft magnetic powder material and application. The insulation coating method comprises the following steps: (1) uniformly mixing low-melting-point metal or alloy powder, silica sol, silane coupling agent and hot curing resin glue solution to obtain coating slurry; (2) uniformly mixing soft magnetic powder and the coating slurry of step (1), and then performing hot-pressing curing forming at a temperature of 60-100 DEG C and under vacuum condition, and then performing hot-pressing sintering treatment under a temperature higher than the melting point of the low-melting-point metal or alloy powder and under an oxygen-containing atmosphere condition to obtain the insulation-coated soft magnetic powder material. The insulation coating method of the application combines the advantages of the organic material insulation coating method and the inorganic material insulation coating method, overcomes the respective defects, and significantly improves the stability and insulation coating effect of the insulation coating layer.

The invention discloses a preparation method of high-purity Nb2O5, belongs to the field of preparation of Nb2O5, and solves the problem of low purity of Nb2O5 prepared by the existing method. The preparation method comprises the steps that a metal niobium ingot with the purity larger than or equal to 99.999% is adopted, and vacuum drying is conducted after surface peeling, dilute nitric acid ultrasonic cleaning and high-purity water flushing are conducted; the pretreated niobium ingot is subjected to a hydrogenation reaction in a pure hydrogen atmosphere, niobium hydride is generated and then crushed, and niobium hydride powder is obtained; carrying out dehydrogenation treatment on the niobium hydride powder under a high vacuum condition; dissolving the metal niobium powder with electronic-grade hydrofluoric acid, and filtering to obtain fluorine niobic acid filtrate; performing multi-stage counter-current extraction and reverse extraction on the fluobiobic acid filtrate by adopting an extracting agent to obtain fluobiobic acid reverse extraction liquid; introducing high-purity ammonia gas into the fluobiobic acid strip liquor, and precipitating to generate niobium hydroxide; ageing, filtering and washing with high-purity water for multiple times to obtain a niobium hydroxide filter cake; and calcining the niobium hydroxide filter cake in a high-purity oxygen atmosphere in stages to obtain niobium pentoxide. The niobium pentoxide prepared by the method disclosed by the invention is high in purity.

The invention relates to a non-toxic luminescence-based colorimetric sensor and methods of using the sensor in food contact and similar applications. The luminescence-based sensor can be used to assess oxygen concentration, particularly in controlled oxygen atmospheres such as food packaging.

The application belongs to the technical field of carbonyl sulfur hydrolysis catalysts, and discloses a high-efficiency sulfur-resistant catalyst for carbonyl sulfur hydrolysis, a preparation method and application thereof.The preparation method comprises the following steps: (1) preparing a porous ceramic carrier containing alumina, titanium dioxide and zirconium dioxide; (2) in-situ growing a metal organic framework material containing lanthanum, bismuth and cerium on the surface of the porous ceramic carrier by using a solvothermal method; (3) performing a calcination treatment on the porous ceramic carrier loaded with the metal organic framework material in an oxygen-containing atmosphere to obtain a catalyst precursor; and (4) performing a reducing gas plasma bombardment treatment on the catalyst precursor to obtain the high-efficiency sulfur-resistant catalyst.The high-efficiency sulfur-resistant catalyst has high-efficiency low-temperature activity, excellent sulfur resistance and long service life.

The application discloses a molybdenum monatomic anchored gamma-Fe2O3 photoelectric cathode catalyst, a preparation method of an electrode thereof and application of the catalyst to photoelectrocatalytic degradation of pollutants in water bodies. The molybdenum monatomic anchored gamma-Fe2O3 photoelectric cathode catalyst comprises a gamma-Fe2O3 carrier and molybdenum atoms anchored on the surface of the gamma-Fe2O3 carrier in the form of monatomic atoms, wherein the molybdenum atoms are anchored by replacing part of iron sites in the gamma-Fe2O3 crystal lattice. The preparation method comprises the following steps: mixing and impregnating a molybdenum precursor solution with gamma-Fe2O3, and evaporating dry; and performing twice calcination on the obtained solid to obtain the molybdenum monatomic anchored gamma-Fe2O3 photoelectric cathode catalyst; in the twice calcination, the first time calcination is performed at 250-350 DEG C in an oxygen-containing atmosphere, and the second time calcination is performed at 450-550 DEG C in an inert atmosphere.

The application relates to the technical field of quartz crystal purification, and particularly discloses a method for eliminating radioactive elements in quartz crystals, which comprises the following steps: adding quartz sand into a composite cleaning solution, stirring and cleaning, then performing solid-liquid separation and water washing to obtain pretreated quartz sand; performing heat treatment on the pretreated quartz sand in an oxygen-containing atmosphere at 850-1000 DEG C for 2-4 hours to obtain heat-treated quartz sand; rapidly cooling the heat-treated quartz sand in cooling water at 10-30 DEG C for 15-30 seconds, then crushing and screening to obtain crushed quartz sand; adding the crushed quartz sand into a selective acid cleaning solution under stirring to perform an acid cleaning reaction, then performing solid-liquid separation, washing and drying after the reaction to obtain low-radioactivity quartz sand. The composite cleaning solution and the selective acid cleaning solution are used in cooperation to efficiently remove radioactive elements such as uranium and thorium in the quartz crystals, and the physical and chemical properties of the quartz crystals can meet the requirements of high-end semiconductor and optical applications.