83 results about "Sodium titanate" patented technology

The invention relates to a sodium ion battery, and belongs to sodium ion batteries. The battery cell of the sodium-ion battery comprises a positive plate, a negative plate and an electrolyte, the active material of the positive plate is carbon-coated aluminum-doped sodium ferric sulfate; the chemical formula of the aluminum-doped sodium ferric sulfate is Na < 2 + 2y > Fe < 2-x-y > Al < x > (SO4) 3, x is more than or equal to 0.01 and less than or equal to 0.05, and y is more than or equal to 0.1 and less than or equal to The particle size of the carbon-coated aluminum-doped sodium ferric sulfate ranges from 50 nm to 100 nm; the weight ratio of a carbon coating layer in the carbon-coated aluminum-doped sodium ferric sulfate is 1%-5%; the active material of the negative plate is carbon-coated sodium titanate; the specific surface area of the carbon-coated sodium titanate is 20 m < 2 > / g to 25 m < 2 > / g; the weight ratio of a carbon coating layer in the carbon-coated sodium titanate is 0.5%-3%. Volume expansion is jointly inhibited through structural stability of positive and negative electrode materials, and the cycle life is prolonged.

The invention provides a preparation method of a metal-doped sodium titanate negative electrode material, which comprises the following steps: S1, preparation of a hydrolysis solution: dissolving titanyl sulfate and metal A sulfate in water to serve as the hydrolysis solution, the molar ratio of A to Ti being (0.01-0.5): 1; s2, preheating a base solution, namely adding a proper amount of deionized water into a reaction kettle, and preheating to 80-110 DEG C; s3, hydrolysis: in a stirring state, adding a hydrolysis solution into the reaction kettle at a constant speed, and keeping the temperature of a system in the reaction kettle constant; s4, preparing metatitanic acid: cooling the hydrolyzed slurry to room temperature, washing with water, and drying to obtain metal-doped metatitanic acid; and S5, preparing sodium titanate: uniformly mixing a sodium source and the metal-doped metatitanic acid according to the molar ratio of sodium to titanium of 2: 3, calcining in an argon atmosphere, and naturally cooling to obtain the metal-doped sodium titanate. The metal-doped sodium titanate prepared by the method is low in cost, simple and feasible in process and excellent in product performance.

The invention provides an ultra-low carbon duplex stainless steel all-position welding flux-cored wire and a welding method thereof.The outer skin of the flux-cored wire is a stainless steel strip, the flux-cored wire is filled with powder, and the powder comprises, by mass, 18-25% of natural rutile, 20-30% of stainless steel powder, 20-30% of stainless steel powder, 20-30% of stainless steel powder and the balance stainless steel powder. 3-5% of sodium titanate; 5-10% of quartz sand; 0.5 to 4 percent of zircon sand; 1-3% of sodium fluoride; 15 to 25 percent of ferromolybdenum; 3-6% of nitrided ferrochrome; 2-4% of electrolytic manganese; 5-8% of nickel powder; 27 to 32 percent of metal chromium; 0.5-2% of magnesium powder; 0.5 to 1.5 percent of bismuth oxide; and 1-4% of silicon iron. The flux-cored wire is used for all-position welding of third-generation duplex stainless steel, welding spatter is small, and weld joint forming is good; the carbon content of a weld joint is extremely low, and through component and welding process control, weld joint metal has strength, plasticity, toughness and corrosion resistance equivalent to those of base metal. And the double requirements of high strength and toughness and high corrosion resistance in the manufacturing fields of submarine pipeline laying, shipbuilding, marine gas field exploitation and the like are ensured.

The invention discloses sodium titanate with a layered crystal structure, a preparation method of the sodium titanate and application of the sodium titanate in a water-based magnesium ion battery, and belongs to the technical field of water-based magnesium ion batteries. According to the invention, the sodium titanate with a layered crystal structure is used as the negative electrode material of the aqueous magnesium ion battery, and due to excellent chemical and structural stability, the sodium titanate can realize reversible Mg < 2 + > intercalation / deintercalation in an aqueous magnesium electrolyte. According to the invention, Na2Ti2O5 and Na2Ti3O7 materials are synthesized by a hydrothermal method and a high-temperature annealing process. In a magnesium chloride electrolyte, the two sodium titanate materials both show extremely low charge and discharge potentials (Na2Ti2O5,-1.3 to-0.6 V vs.SCE; sCE (-1.5 to-1 V vs.SCE) and relatively good cycling stability are achieved. In addition, the charge-discharge specific capacity of the Na2Ti2O5 half cell under the current density of 2A / g is up to 213mAh / g, and the high specific capacity of 150mAh / g is still kept under the high current density of 10A / g. The sodium titanate is an ideal aqueous magnesium battery negative electrode material, has the advantages of low cost and environmental friendliness, and has a great application prospect in the field of aqueous magnesium ion energy storage.

The invention discloses a micro-arc oxidation surface modified biomedical titanium alloy with good friction corrosion resistance and a preparation method of the micro-arc oxidation surface modified biomedical titanium alloy. The micro-arc oxidation surface modified biomedical titanium alloy comprises a titanium alloy base material and a micro-arc oxidation coating located on the surface of the titanium alloy base material. The micro-arc oxidation coating comprises a compact layer and a sparse layer which are sequentially connected with the titanium alloy base material. EDS element analysis shows that the micro-arc oxidation coating contains a sodium element, an oxygen element, an aluminum element, a phosphorus element, a potassium element, a titanium element and a niobium element. The preparation method comprises the following steps: preparing a micro-arc oxidation electrolyte, wherein the micro-arc oxidation electrolyte comprises sodium titanate, potassium hydroxide, sodium hexametaphosphate and niobium particles; the titanium alloy base material serves as an anode, a stainless steel sheet serves as a cathode, the micro-arc oxidation electrolyte is loaded into an electrolytic cell, then a micro-arc oxidation electrolytic reaction is conducted, and the micro-arc oxidation coating is generated on the surface of the titanium alloy base material.

The invention discloses an orthopedic implant with antibacterial and osteogenesis-promoting characteristics and a preparation method thereof, and belongs to the technical field of medical materials.The preparation method comprises the steps that a titanium stent subjected to acid treatment is placed in a NaOH solution, and a sodium titanate coating is formed on the surface of the titanium stent after alkali heat treatment; after annealing, immersing into a mixed solution of EDTA-CaNa2 and NaH2PO42H2O, and after heating reaction, forming a hydroxyapatite coating on the surface of the sodium titanate coating; immersing the hydroxyapatite coating into a mixed solution of glucolactone and sodium alginate, controlling the pH value of the mixed solution to be 5, and forming a porous hydrogel coating on the surface of the hydroxyapatite coating after reaction; and soaking the loaded medicine to obtain the orthopedic implant. A multi-layer structure of the sodium titanate coating, the hydroxyapatite coating and the porous hydrogel coating is sequentially formed on the titanium alloy stent, and finally, the medicine is loaded, so that the titanium alloy stent has various characteristics of resisting bacteria, promoting osteogenesis and the like.

A Na2Ti7O15 doped Na2Ti3O7 sodium titanate electrode material, and a preparation method therefor and a use thereof. The electrode material has a porous block structure formed by stacking nanorods. The electrode material is synthesized by a simple solid-phase method, and is obtained by carrying out ball milling on precursors sodium carbonate and anatase-phase titanium dioxide in proportion, and then carrying out microwave sintering in air; the addition of Na2Ti7O15 increases the exposure of (100) sodium storage crystal face and decreases the exposure of (003) crystal face of Na2Ti3O7 sodium titanate; and Na2Ti7O15 has four TiO6 octahedrons in one structural unit, and has more sodium storage sites and wider sodium-ion diffusion channels, thereby improving the specific capacity and rate performance of the material. Upper and lower layers of TiO6 octahedrons in Na2Ti7O15 are connected to each other, such that the structure is more stable in a sodium-ion intercalation / deintercalation process, thereby improving the long cycle stability of the material.

The application relates to a sodium ion battery negative electrode material and a preparation method and application thereof, and belongs to the technical field of sodium ion batteries. The sodium ion battery negative electrode material comprises sodium titanate and a composite coating layer coated on the surface of the sodium titanate, and the composite coating layer comprises titanium carbide and carbon; the mass ratio of the sodium titanate, the titanium carbide and the carbon is (70-90):(5-15):(2-10). Through the compounding of the sodium titanate and the composite coating layer (titanium carbide and carbon), the conductivity is significantly improved, the 10C capacity retention rate is increased from 30% to 70%, and the coulomb efficiency is increased from 65% to 95%.

The present invention provides a preparation method of a structure-modified sodium ion battery positive electrode material, comprising the following steps: S1, mixing a sodium source, an iron source, a phosphorus source, a first carbon source, a structure modifier, and deionized water, adding the mixture to a high-gravity reactor rotating at 25,000 to 35,000 rpm, reacting at a temperature of 80 to 100° C. for 1 to 2 h, drying, and then calcining at 400 to 650° C. for 8 to 12 h in an inert gas atmosphere to obtain a precursor, wherein the structure modifier is at least one of sodium vanadate, sodium titanate, sodium manganate, sodium cobaltate, sodium chromate, metatitanic acid, magnesium oxide, copper oxide, zinc oxide, and yttrium oxide; S2, mixing the precursor, a second carbon source, and a chelate solution, adjusting the pH to 2.5 to 4.0, grinding the mixture at a temperature of 60 to 90° C. until the D50 is less than 0.95 μm, spray drying, and calcining at 400 to 650° C. for 8 to 12 h in an inert gas atmosphere. h obtain the structure-modified sodium ion battery positive electrode material.

This invention discloses a type of sodium titanate with a layered crystal structure, its preparation method, and its application in aqueous magnesium-ion batteries, belonging to the field of aqueous magnesium-ion battery technology. This invention uses sodium titanate with a layered crystal structure as the negative electrode material in aqueous magnesium-ion batteries. Due to its excellent chemical and structural stability, sodium titanate can achieve reversible magnesium deposition in aqueous magnesium electrolytes. 2+ Intercalation / extraction. This invention synthesizes Na via a hydrothermal method and a high-temperature annealing process. 2 Ti 2 O 5 And Na 2 Ti 3 O 7 Materials. In magnesium chloride electrolyte, both sodium titanate materials exhibit extremely low charge / discharge potentials (Na). 2 Ti 2 O 5 -1.3 to -0.6V vs. SCE; Na 2 Ti 3 O 7 (-1.5 to -1V vs. SCE) and good cycle stability. Furthermore, Na... 2 Ti 2 O 5 The half-cell exhibits a charge-discharge specific capacity of up to 213 mAh / g at a current density of 2 A / g, and maintains a high specific capacity of 150 mAh / g even at a high current density of 10 A / g. The sodium titanate of this invention is an ideal anode material for aqueous magnesium batteries, possessing both low cost and environmental friendliness, and shows great promise for application in the field of aqueous magnesium-ion energy storage.

The invention discloses a method for implementing atomic-scale regulation and control on platinum sites on TiO2 nanotubes and applying the platinum sites to light-driven methane dry reforming, provides a preparation method of a light-driven methane dry reforming catalytic material, and relates to implementation of atomic-scale precise regulation and control on the platinum sites on the TiO2 nanotubes. Therefore, two greenhouse gases, namely CO2 and CH4, are converted into synthesis gases (H2 and CO) under relatively mild conditions, and raw materials are provided for Fischer-Tropsch synthesis or preparation of chemicals with higher value. The preparation method comprises the following steps: by taking tubular sodium titanate obtained by alkalizing anatase as a substrate and tetraammineplatinum dichloride as a platinum source, carrying out ion exchange on positively charged platinum ammonia ions and substrate sodium ions by virtue of an electrostatic adsorption method, so that the platinum ammonia ions are embedded into the substrate; by controlling the calcination temperature and duration under different atmospheres, sodium titanate is promoted to be converted into TiO2, redundant ligands are effectively removed, and meanwhile precise regulation and control from Pt single atoms to Pt sub-nanocluster sites are achieved. The electronic metal-carrier interaction between the Pt site and the carrier induces local charge rearrangement, promotes directional adsorption and activation of CO2 and CH4 molecules at active sites, and shows excellent methane dry reforming activity and stability under xenon lamp simulated illumination and focused natural sunlight.

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

The invention relates to the technical field of titanium slag separation, in particular to a method for separating perovskite and preparing a battery material based on blast furnace titanium slag. According to the method, the silicate mineral phase in the blast furnace titanium slag is reconstructed so that the silicate mineral phase can be completely dissolved by acid, meanwhile, low-valence titanium in the silicate mineral phase is oxidized into high-valence titanium, the high-valence titanium is enriched in the perovskite phase, and then separation and purification of CaTiO3 in the titanium slag are achieved; furthermore, sodium titanate hydrate and calcium titanate hydrate with porous network structures are loaded on the surface of the separated and purified CaTiO3, so that the bonding strength of the CaTiO3 and the polyethylene diaphragm can be enhanced, and the thermal stability of the solid electrolyte interface layer of the lithium battery prepared on the basis of the high titanium slag is further improved. In a word, the invention not only provides a new method for separating and purifying the blast furnace titanium slag, promotes high-value utilization of the blast furnace titanium slag, but also provides a new thought and method for preparing the solid electrolyte interface layer of the lithium battery, and has a wide application prospect.

The present invention provides a preparation method and application of an antibacterial coating on a titanium surface, belonging to the technical field of metal surface treatment. The preparation method includes: pickling the surface of a titanium material to obtain a pickled titanium material; alkalizing the pickled titanium material in an alkaline solution to form a sodium titanate layer and obtain an alkalized titanium material; vertically placing the alkalized titanium material in a reaction solution containing an iron source and a sulfur source for a hydrothermal reaction to obtain a titanium material with an FeS2 coating; wherein, the iron source in the reaction solution includes any one of ferric chloride, ferrous gluconate, ferrous sulfate, and ferric nitrate, and the sulfur source includes any one of tetraethylthiuram disulfide, thiourea, and thioacetamide. This method prepares a dense-structured FeS2 coating with good bonding force to the pure titanium substrate on the surface of pure titanium by using the vertical solvothermal method, which can improve the antibacterial performance of the pure titanium material and further enhance the biocompatibility of the medical pure titanium material.

The present invention provides a preparation method and application of a lithium iron titanate / carbon quantum dot composite material, belonging to the field of electrochemical energy storage technology. The preparation method comprises the following steps: uniformly mixing anatase and sodium hydroxide, ultrasonically treating, and hydrothermally activating the mixture; repeatedly centrifuging and adding deionized water to the activated product, sodium titanate, until the supernatant is neutral, and drying to obtain an acid-washed product; grinding, sieving, and calcining the acid-washed product to obtain bronze-phase TiO2(B); using citric acid as a chelating agent, dissolving CH3COOLi·2H2O, FeCl2·4H2O, TiO2(B), and carbon quantum dots in anhydrous ethanol, stirring in a water bath to obtain a gel, vacuum drying and sieving, and calcining under an inert atmosphere to obtain a pre-calcined material; and sequentially ball milling and sieving the pre-calcined material, followed by final calcination under an inert atmosphere to obtain a Li2FeTiO4 / carbon quantum dot composite material. The present invention combines carbon quantum dots with lithium iron titanate to form a lithium-ion battery positive electrode composite material with enhanced electrochemical performance. The preparation process is simple, low-cost, and suitable for large-scale commercial production.

The present invention discloses a ruthenium-loaded titanate nanowire catalyst, a preparation method thereof and an application thereof, belonging to the technical field of ruthenium-loaded catalysts. The preparation method of the ruthenium-loaded titanate nanowire catalyst comprises Step 1: dispersing nano-titanium dioxide in a solvent to obtain a first mixture; reacting the first mixture obtained in Step 1 under a certain pressure, and obtaining titanate nanowires after the reaction ends; dispersing the titanate nanowires obtained in Step 2 in a solvent to obtain a second mixture; adding an aqueous solution of ruthenium chloride to the second mixture obtained in Step 3, and stirring to obtain a third mixture; adding an aqueous solution of sodium borohydride to the third mixture obtained in Step 4, and stirring to obtain a fourth mixture, and obtaining a first precursor, namely the ruthenium-loaded titanate nanowire catalyst, after post-treatment. The catalyst prepared by the present invention shows excellent catalytic stability for the hydrocracking reaction of polyolefins, can be extended to the hydrocracking of commercial waste plastics, and the catalyst can be recovered and reused after the reaction ends.

The invention relates to a preparation method and application of chromium-doped sodium titanate with high cycle stability, the chromium-doped sodium titanate is formed by solid-phase sintering of Na2CO3, nano TiO2 and Cr2O3, and optimized Cr-Na2Ti3O7 has excellent cycle stability; the preparation method comprises the following steps: taking a certain amount of Na2CO3, nano TiO2 and Cr2O3 in a corresponding proportion, adding a small amount of isopropanol, and carrying out ball milling in a ball milling instrument for 5-8 hours; completely drying in a drying box, and putting the dried product into a tubular furnace; in a closed atmosphere of high-purity argon, carrying out solid-phase sintering for 10-12 hours by adopting a step-by-step calcination method, and naturally cooling to room temperature; when the material is used as a negative electrode of a sodium ion battery, the coordination environment of sodium ions can be changed, an interlayer Ti-O bond is optimized so as to optimize an interlayer structure, the irreversible capacity generated by Na2Ti3O7 in the charge-discharge cycle process is obviously reduced, and the cycle stability and the rate performance of the battery are improved; the preparation method has important significance for developing a high-performance negative electrode material of the sodium-ion battery and improving the performance of the sodium-ion battery.

The application discloses an aluminum alloy micro-arc oxidation plating solution and a preparation method and application thereof. The aluminum alloy micro-arc oxidation plating solution comprises water, potassium hydroxide and the following preparation raw materials: sodium hexametaphosphate 8-15 g / L; sodium silicate 10-18 g / L; sodium metavanadate 10-15 g / L; sodium molybdate 10-18 g / L; ethylene glycol 1-5 g / L; beta-glycerophosphoric acid sodium 2-5 g / L; sodium hexafluorotitanate 3-6 g / L; boric acid 1-3 g / L; and alkaline aluminum oxide sol, wherein the content of the aluminum oxide is 0.1-0.3 g / L; and the pH of the micro-arc oxidation plating solution is 9-12. The plating solution is suitable for surface treatment of aluminum alloy, can significantly improve the hardness, wear resistance and corrosion resistance of the material, and makes the surface more smooth and flat. The application further provides the preparation method and application of the aluminum alloy micro-arc oxidation plating solution.

The invention discloses a modified titanium implant as well as a preparation method and application thereof. The modified titanium implant sequentially comprises a titanium matrix, a tetragonal phase barium titanate layer and an iron-tannic acid network structure layer from inside to outside. The modified titanium implant is obtained by taking sodium titanate as a seed layer, preparing tetragonal-phase barium titanate on the surface of a titanium substrate and then loading an iron-tannic acid network structure on the surface of the tetragonal-phase barium titanate. A barium titanate structure and an iron-tannic acid network are combined for the first time, the possibility of multifunctional triggering is given to the surface of the modified titanium implant, and the iron-tannic acid network not only can improve the biocompatibility of the surface of the modified titanium implant, but also can enhance the light absorption capacity of the material; even in the future research, an antibacterial mode triggered by multiple exogenous sources can be considered.

This invention discloses a Na2Ti7O 15 Na₂Ti₃O₇ sodium titanate electrode material, its preparation method, and its application. This electrode material is a porous, blocky structure composed of stacked nanorods. It is synthesized by a simple solid-state method, where sodium carbonate precursor and anatase titanium dioxide are ball-milled in a specific ratio and then microwave-sintered in air. 15 The addition of [a specific ingredient] increases the exposure of the (100) sodium storage crystal face in Na2Ti3O7 sodium titanate, while decreasing the exposure of the (003) crystal face; Na2Ti7O 15 The presence of four TiO6 octahedrons within a single structural unit increases the number of sodium storage sites and widens the sodium ion diffusion channels, thereby improving the material's specific capacity and rate performance. (Na2Ti7O) 15 The two layers of TiO6 octahedrons are interconnected, making the structure more stable during sodium ion insertion / extraction, thereby increasing the long-term cycling stability of the material.

The invention provides a preparation method and application of a titanium surface antibacterial coating, and belongs to the technical field of metal surface treatment.The preparation method comprises the steps that the surface of a titanium material is subjected to acid pickling, and an acid-pickled titanium material is obtained; the acid-washed titanium material is placed in alkali liquor to be alkalized, a sodium titanate layer is formed, and an alkalized titanium material is obtained; vertically placing the alkalized titanium material in a reaction solution containing an iron source and a sulfur source, and carrying out a hydrothermal reaction to obtain a titanium material containing a FeS2 coating; wherein the iron source in the reaction solution comprises any one of ferric chloride, ferrous gluconate, ferrous sulfate and ferric nitrate, and the sulfur source comprises any one of tetraethylthiuram disulfide, thiourea and thioacetamide. According to the method, a FeS2 coating which is compact in structure and good in bonding force with a pure titanium substrate is prepared on the pure titanium surface through a vertical solvothermal method, the antibacterial performance of the pure titanium material can be improved, and then the biocompatibility of the medical pure titanium material is improved.

The invention relates to a gradient piezoelectric buffer layer, a preparation method and a solid-state battery. The gradient piezoelectric buffer layer comprises a sodium bismuth titanate nanoparticle coating layer, a lithium phosphate ion conduction layer and a PVDF-ZnO composite electrolyte layer which are arranged in a stacked mode. The preparation raw materials of the sodium bismuth titanate nanoparticle coating layer comprise a sodium source, a bismuth source, a titanium source, a mineralizer and a ternary positive electrode material. According to the invention, a three-layer structure of piezoelectric buffer layer-ion conduction layer-piezoelectric composite electrolyte is constructed, the volume change of the electrode is dynamically compensated by using the inverse piezoelectric effect of the piezoelectric material, and stress regulation and ion transmission are synchronously realized. Compared with a traditional passive buffering strategy, the method has the advantages that the interface impedance can be reduced, the cycling stability is remarkably improved, and technical support is provided for industrialization of high-energy-density (greater than or equal to 400Wh / kg) solid-state batteries.

The application relates to a sodium titanate nanofiber / reduced graphene oxide composite electrode material and a preparation method and application thereof. The composite electrode material has a two-dimensional sheet structure, the particle size is 1-6 mu m, the thickness is 10-20 nm, is composed of a few-layer reduced graphene oxide and sodium titanate nanofibers with a diameter of 5-10 nm loaded on the reduced graphene oxide, and is prepared by taking the few-layer reduced graphene oxide as a template, uniformly loading titanium dioxide particles, and then carrying out hydrothermal treatment in an alkali solution. Compared with the prior art, the synthesis method is simple in process, easy to scale up, and high in controllability. As a negative electrode of a sodium ion battery or a positive electrode of a sodium battery, the sodium titanate nanofiber / reduced graphene oxide composite electrode material has the advantages of high initial coulomb efficiency, low working voltage, high capacity, excellent rate characteristics and cycle stability, and has a broad market application prospect.

The application belongs to the field of sodium ion batteries, and discloses a modified preparation method of a sodium titanate manganese phosphate positive electrode material of a sodium ion battery, which comprises the following steps: S1, weighing a metal ion chelating agent to prepare a solution I; S2, weighing a manganese source, a titanium source and a sodium source, and dissolving them in the solution I to obtain a solution II; S3, dissolving a Li, Mg or Ca source material in the solution II to obtain a solution III; weighing a phosphate to prepare a solution IV; S4, dropping the solution IV into the solution III drop by drop; and S5, stirring under an oil bath condition, and then drying and calcining, so that the modified sodium titanate manganese phosphate positive electrode material is obtained. According to the application, the low-orbital energy level elements Li, Mg or Ca are introduced into the sodium titanate manganese phosphate Na3MnTi(PO4)3 positive electrode material, and the preparation method is controlled, so that the modified sodium titanate manganese phosphate positive electrode material is obtained, the electronic configuration of Li(Mg, Ca)-O-Mn is constructed, the inhibition of the anti-site defect is realized, and the improvement of the electrochemical performance is facilitated.

This invention belongs to the field of metallurgical solid waste resource utilization technology, specifically disclosing an iron-based additive, its preparation method, and its application. The preparation method includes: mixing red mud, sodium salt, and a reducing agent; subjecting the mixture to reduction roasting to obtain reduced clinker; grinding and separating the reduced clinker by magnetic separation to obtain iron concentrate, thus obtaining the iron-based additive. This invention uses red mud, sodium salt, and a reducing agent stored in alumina plants as raw materials. The sodium salt significantly lowers the reduction temperature of iron ore, and by controlling the temperature and the amount of reducing agent added, the hematite is partially or completely reduced. The resulting iron-based additive is returned to the Bayer process leaching, which can significantly improve the alumina leaching rate. Simultaneously, the titanium minerals in the obtained titanium-containing tailings exist in a specific phase or in the form of amorphous sodium titanate, exhibiting higher reactivity. This invention realizes the recycling and value-added utilization of solid wastes such as red mud, and has good application prospects.

The present application relates to the technical field of welding material, and discloses a kind of ultra-low carbon bainite high-strength steel matched flux-cored wire for high-speed train bogie and welding method.The flux-cored wire of the present application includes outer skin and flux filled in the outer skin, and the flux includes the following components by mass fraction: sodium fluoride 23-28%, CaCO3 8-15%, sodium titanate 12-15%, natural rutile 5-10%, potassium feldspar 4-7%, electrolytic manganese 6-10%, ferrosilicon 4-6%, nickel powder 6-9%, copper powder 0.5-0.8%, molybdenum iron 2.5-4%, niobium iron 0.2-0.3%, titanium iron 1.2-1.8%, and iron powder 8.6-13.1%.The flux-cored wire of the present application is used for welding of the steel in the manufacture of high-speed train bogie frame, and the weld metal has excellent strength, toughness and corrosion resistance, the weld is fine and has low risk of fatigue cracking, and meets the high standard requirements in the manufacture and service of high-speed train bogie.

According to the preparation method of the efficient and stable photo-thermal catalytic methane dry reforming catalyst provided by the invention, CO2 and CH4 can be efficiently and stably converted into synthesis gas (CO + H2) under relatively mild photo-thermal conditions by constructing a bifunctional NiRu bimetal active site. Specifically, perovskite is used as a precursor, a sodium titanate nanotube precursor is prepared through an alkaline hydrothermal method, and then the TiO2 nanotube carrier (TNT) is synthesized through acidification and calcination. Then, nickel chloride is used as a nickel source, and Ni particles are loaded to the surface of TNT through a wet impregnation method; on the basis, ammonium hexachlororuthenate is used as a ruthenium source, Ru < 4 + > is spontaneously reduced by Ni particles through an electric position exchange method, and a Ru site is loaded near a Ni site, so that the construction of a bimetallic site is realized. In the photo-thermal catalytic methane dry reforming reaction, Ni and Ru sites are respectively responsible for activating CH4 and CO2. According to the design, the advantages of low cost and high activity of Ni and high stability of Ru are taken into consideration, a remarkable synergistic effect is generated, the catalytic activity of the catalyst exceeds the simple addition of the activity of a corresponding single-metal catalyst, so that efficient activation of non-polar reactants is realized, and finally efficient and stable catalytic performance is achieved.

The invention relates to a doped sodium trititanate composite material as well as a preparation method and application thereof, and belongs to the technical field of sodium ion batteries. The doped sodium trititanate composite material comprises: a matrix composed of sodium titanate, aluminum doped in the surface region of the sodium titanate and magnesium doped in the bulk phase region of the sodium titanate; the chemical formula of the matrix is Na < 2-2x > Mg < x > Ti < 3-0.75 y > Al < y > O < 7 >, x is more than or equal to 0.01 and less than or equal to 0.05, and y is more than or equal to 0.002 and less The carbon conductive layer is formed by amorphous carbon and coats the surface of the substrate; and the electrolyte layer is composed of Na3PS4 and coats the surface of the carbon conductive layer. From the perspective of material thermodynamics, phase change is effectively inhibited by Al / Mg doping; in the aspect of interface chemistry, Na3PS4 is adopted to stabilize a solid electrolyte interface; and meanwhile, the preparation process is optimized from the aspect of process compatibility, so that the preparation of the doped sodium trititanate composite material with excellent performance is realized.

The invention discloses a method for in-situ construction of a wide-range wavelength visible / ultraviolet titanium dioxide-sodium titanate and titanium dioxide-tungsten trioxide dual heterostructure on the surface of titanium, and relates to a method for constructing the dual heterostructure. The invention aims to solve the problems that the existing TiO2 photocatalyst is poor in organic dye sewage degradation capability and cannot be recycled. The method comprises the following steps: 1, micro-arc oxidation treatment; 2, microwave hydrothermal treatment; 3, ion deposition exchange treatment; and 4, decrystallization and crystallization treatment. The method is used for in-situ construction of a wide-range wavelength visible / ultraviolet titanium dioxide-sodium titanate and titanium dioxide-tungsten trioxide dual heterostructure on the surface of titanium.

The present invention relates to a high temperature resistant and low damage well killing fluid, comprising the following raw materials in parts by mass: 100-150 parts of water, 20-60 parts of composite salt, 1.6-2.5 parts of modified guar gum, 1-1.7 parts of plant alkyl polysaccharide, 2-3 parts of functional polymer, 0.02-0.04 parts of sodium fluorotitanate; the modified guar gum is obtained by reacting hydroxypropyl guar gum and polyethylene glycol diglycidyl ether; the composite salt is a compound of inorganic salt and organic salt; the inorganic salt does not include halogen salt. The well killing fluid of the present invention has a simple formula, uses a composite system of modified guar gum, plant alkyl polysaccharide and composite salt, is environmentally friendly and non-toxic, has good plugging performance, low filtration loss, avoids leakage damage to the reservoir, has high viscosity, adjustable density, can withstand 180°C high temperature aging, is biodegradable, has little pollution to the core, is a non-destructive or low-loss solid-free well killing fluid, and can be widely used in various oil wells.