589 results about "Acid etching" patented technology

The invention discloses a porous titanium-based implant with a photo-thermal surface and a preparation method and application of the porous titanium-based implant, and belongs to the technical field of biomedical materials. The preparation method comprises the steps that a porous titanium substrate is prepared through 3D printing, then flowing acid etching treatment and anodic oxidation treatment are conducted in sequence, then the porous titanium substrate is placed in photo-thermal coating dispersion liquid for reaction, cleaning and drying are conducted, and the porous titanium-based implant with the photo-thermal surface is obtained. The photo-thermal coating dispersion liquid is obtained by dispersing MXene-ZnO composite particles in a dopamine hydrochloride solution. The porous titanium-based implant provided by the invention can be rapidly heated to a proper temperature under the irradiation of near-infrared light, and has good antibacterial, anti-tumor and osteogenesis promoting properties and biocompatibility.

The invention belongs to the technical field of biomedical engineering, and particularly relates to a preparation method and application of a titanium dental implant surface coating, and the preparation method comprises the following steps: S1, pretreatment of a titanium dental implant matrix: sequentially carrying out grinding and polishing, ultrasonic cleaning and acid etching treatment; s2, preparation of a coating precursor solution: adding nano-hydroxyapatite powder, chitosan, gelatin and titanium dioxide nanoparticles into deionized water, stirring to form a suspension, then adding a silver nitrate solution, and continuously stirring to form the coating precursor solution; s3, coating a coating: coating the surface of the pretreated titanium dental implant matrix with the coating precursor solution by adopting an electrophoretic deposition method; and S4, drying and sintering: drying and sintering the coated titanium dental implant. According to the preparation method of the titanium dental implant surface coating, provided by the invention, the bonding strength between the coating and the titanium dental implant matrix can be improved.

The invention discloses an oil-water well acidification continuous construction electric control system based on multi-parameter monitoring, and relates to the technical field related to acidification control in oil-gas field development, and the system comprises a multi-source data fusion monitoring module which integrates wellhead pressure, temperature, flow, pH value, H2S concentration and acid liquid conductivity, and an underground microwave imaging sensor carries out multi-physical quantity collection; a multi-objective optimization controller is designed, and the acid etching depth, the crack flow conductivity and the construction cost are balanced; the self-adaptive construction control module is based on a variable-frequency and variable-speed acid pump system controlled by a fuzzy sliding mode and is used for realizing stepless regulation of displacement; an intelligent shunting system is arranged, and acid liquor distribution is dynamically adjusted according to the suction volume of each layer section. According to the variable-frequency acid pump system based on fuzzy sliding mode control, stepless adjustment of the displacement is achieved; the intelligent flow distribution system dynamically prepares liquid according to the suction volume of each layer section; and through a three-stage safety interlocking mechanism, power can be cut off and emergency acid discharge can be started within 0.5 second when the temperature rise is greater than or the pressure suddenly changes, so that the well control risk is reduced.

The invention relates to the technical field of lithium ion battery negative electrode materials, and discloses a preparation method and application of a high-efficiency silicon-carbon composite graphite material, and the preparation method comprises the following steps: S1, carrying out porosity and size regulation and control on silicon particles: carrying out ball milling on industrial-grade silicon powder to obtain nano silicon particles, and carrying out acid etching to form a porous structure; s2, functional surface treatment and interface optimization: introducing functional molecules to the surfaces of the silicon particles and coating a layer of ultrathin SiO2 protective film; and S3, carbon coating and flexible protection layer construction: performing pyrolysis on the porous silicon particles by using a carbon source to form a uniform carbon coating layer which is applied to a lithium ion battery negative electrode material, and the lithium ion battery is used for an electric vehicle, a power grid energy storage system and portable electronic equipment. Through the collaborative design of the flexible protection layer, the double-layer carbon coating and the gradient coating, the technical bottlenecks of the silicon-based negative electrode material in the aspects of long cycle stability, high rate performance and interface chemical stability are systematically solved.

The invention relates to a preparation method of a local ITO interconnected perovskite-TOPCon laminated cell, which comprises the following steps: taking an n-type monocrystalline silicon wafer as a substrate, cleaning and texturing, diffusing boron on the back to form a P + emitter, oxidizing at high temperature, and treating the surface through acid etching and alkali polishing; sequentially preparing a tunneling oxide layer and a phosphorus-doped polycrystalline silicon layer on the front surface, annealing and crystallizing, depositing an aluminum oxide film and a multi-layer silicon nitride film on the back surface after cleaning, and depositing a single-layer silicon nitride film on the front surface; preparing a back metal electrode, etching according to a designed pattern to remove a local silicon nitride film on the front surface, sequentially preparing an ITO interconnection layer, a hole transport layer, a perovskite layer, a passivation layer, an electron transport layer and an ITO transparent conductive layer on the front surface, and finally preparing a front metal electrode and solidifying to form a contact electrode. According to the invention, the problems of back corrosion risk, effective area loss and tedious process in the existing method are solved, full-size manufacturing is realized, the cell performance is improved, and industrialization is easier.

The invention provides unequal-thickness ultrathin glass and a preparation method thereof. The preparation method comprises the following steps: (1) pasting a mask on the surface of UTG glass to obtain film-pasted glass; (2) firstly punching a row of laser holes at the center line of the bending area of the film-coated glass by using laser, recording the laser holes as a first row of laser holes, and then coating the bending area with fluoride as a coating material; then laser drilling is symmetrically conducted on the left side and the right side of the first row of laser holes in the direction from the center line of the bending area to the two sides, coating treatment is repeated once every time symmetric laser drilling is completed till the bending area is full of the laser holes, and the coated glass is obtained; (3) carrying out indirect acid etching on the bending area on the front surface of the coated glass by adopting hydrochloric acid to form an arc-shaped thinned surface so as to obtain roughly etched glass; and (4) carrying out polishing treatment on the rough etching glass to obtain the unequal-thickness ultra-thin glass. The method provided by the invention can significantly improve the flexibility and bending characteristics of the unequal-thickness ultrathin glass.

The invention belongs to the technical field of electrochemistry, and provides a monatomic iridium-based alloy cluster catalyst and a preparation method and electrocatalysis application thereof, and the preparation method comprises the following steps: low-pressure gas-phase capillary filling: mixing an iridium organic metal precursor, a dopant metal organic precursor, a microporous carrier material and a solvent, and drying to obtain mixed powder, the mixed powder is placed in an ampoule bottle with a certain vacuum degree and sealed, then the ampoule bottle is placed in a rotary drying oven for high-temperature heat treatment, and powder a is obtained; temperature-controlled acid etching: mixing the powder a and an acid solution for reaction in the environment of protective gas to obtain black powder; the black powder is placed in H2 / Ar mixed gas for programmed heat treatment, and the monatomic iridium-based alloy cluster catalyst is obtained. The monatomic iridium-based alloy cluster catalyst prepared by the method provided by the invention shows mass activity and catalytic durability which are obviously superior to those of commercial platinum carbon in alkaline hydroxide catalysis, and has a practical application prospect.

The invention discloses a compatible molybdenum-aluminum mixed acid etching solution which comprises the following components in percentage by mass: 4%-7% of nitric acid, 55%-65% of phosphoric acid, 17%-28% of acetic acid, 0.5%-3% of an oxidizing additive, 0.05%-5% of a metal corrosion inhibitor and 10%-20% of deionized water, and the oxidizing additive is ceric nitrate and at least one selected from sodium nitrate, potassium nitrate and ammonium nitrate; the etching liquid does not contain other organic components except for organic carboxylic acid and organic carboxylate. According to the compatible molybdenum-aluminum mixed acid etching solution, on the basis that ceric nitrate is introduced, the content of nitric acid is reduced, the nitrate ion concentration is increased by adding nitrate, the overall oxidation performance of an etching solution system is improved, the etching rate ratio of different metals is adjusted, CD-Bias is reduced, the etching dip angles of a molybdenum single layer and a molybdenum-aluminum laminated layer are controlled to be kept at 20-50 degrees, and the problem of aluminum thorns is solved. The invention further discloses a molybdenum-aluminum etching method based on the compatible molybdenum-aluminum mixed acid etching solution.

The invention belongs to the technical field of catalytic materials, particularly relates to an electrocatalytic anode oxygen evolution reaction catalyst based on an anion exchange membrane electrolytic cell, and particularly relates to a high-entropy oxide electrocatalyst and a preparation method thereof. The high-entropy oxide electrocatalyst is composed of five metal elements of Ni, Co, Fe, Mn and Al, is loaded on a foamed nickel substrate, has a nanosheet structure, is rich in oxygen vacancies on the surface, has excellent electrochemical catalysis performance and stability, and is suitable for electrocatalysis of an electrolytic water anode side in an alkaline environment. According to the preparation method of the high-entropy oxide electrocatalyst, foamed nickel is used as a substrate, salts of five metals of Ni, Co, Fe, Mn and Al which are equal in mole are subjected to hydrothermal synthesis to form a precursor, and then the high-entropy oxide electrocatalyst is prepared through self-etching, annealing oxidation and acid etching, and the high-entropy oxide electrocatalyst is easy and convenient to operate, good in repeatability, controllable in cost, excellent in performance and suitable for large-scale production.

The invention relates to the technical field of lithium battery negative electrode materials, and discloses a preparation method of a lithium battery silicon-carbon composite negative electrode material with high cycle stability, and the preparation method comprises the following steps: carrying out magnesiothermic reduction and acid etching on micron silicon powder and magnesium powder to prepare porous silicon particles; growing carbon nanotubes on the surfaces of the porous silicon particles and in pore channels in situ to construct a three-dimensional conductive network; styrene butadiene rubber and glucose are adopted as a composite carbon source to coat the product, and a composite carbon layer is formed through drying and gradient carbonization; and finally grinding and sieving the carbonized product. According to the preparation method disclosed by the invention, pores are constructed in micron silicon, and the micron silicon is externally coated with the composite carbon layer with flexibility and rigidity, so that the volume expansion of silicon is effectively buffered; the in-situ grown carbon nanotube network provides a stable electron conduction path; the micron-sized substrate reduces the specific surface area of the material and improves the first coulombic efficiency. Therefore, the prepared negative electrode material has high cycling stability and excellent rate capability.

The invention discloses a carbon microsphere-silicon negative electrode material and a preparation method thereof, mesocarbon microbeads are prepared by adding a nano template agent, porous mesocarbon microbead green pellets are obtained through acid etching, and nano-silicon-loaded mesocarbon microbeads are obtained through hydrothermal reaction reduction deposition of organic silicon in pore channels generated through etching, so that the carbon microsphere-silicon negative electrode material is obtained. And coating the outermost layer with a layer of amorphous carbon, and carbonizing to obtain the carbon microsphere-silicon negative electrode material. The mesocarbon microbeads prepared by taking the nano template agent as an additive have the advantages that the particle size distribution is concentrated, the particle size is moderate, a large amount of nano template agent exists inside and on the surface, and rich nano-scale pore channels are obtained after acid etching; in the hydrothermal process, organic silicon is deposited in situ on the outer surfaces of the mesocarbon microbeads and in pore channels to form uniform coating layers, the organic silicon and the mesocarbon microbeads are combined more tightly, the nanometer silicon loaded mesocarbon microbeads are obtained through magnesiothermic reduction, and the advantages of good conductivity, good rate capability and stable cycle performance are achieved.

The invention belongs to the technical field of electrode materials, and relates to coffee residue heat treatment doping-based super capacitor carbon and a preparation method and application thereof, coffee residue is used as a raw material, and after hydrothermal carbonization, staged gradient activation and ultrasonic-acid etching coupling treatment, the super capacitor carbon with a rich pore structure is prepared. According to the process, through precise matching of intrinsic characteristics of coffee grounds and process parameters, a hierarchical porous structure is constructed and is matched with an electron transport network formed by self-doping, so that the technical bottleneck that a traditional biomass carbon material is poor in electrical conductivity and difficult to achieve both ion diffusion efficiency is broken through; the super-capacitor carbon with extremely high specific surface area, excellent electricity storage performance and high energy density is finally obtained; a supercapacitor electrode prepared from the supercapacitor carbon has good charge-discharge performance, large specific capacitance, high energy density and good cycle efficiency; moreover, efficient recycling of the coffee grounds can be achieved, the environment-friendly requirement is met, the process is simple, cost is low, and application and popularization are easy.

The invention belongs to the technical field of lithium ion battery materials, and relates to a preparation method and application of an yttrium-doped porous silicon material, and the preparation method comprises the following steps: S1, preparing a silicon-yttrium alloy precursor; s2, mixing the silicon-yttrium alloy precursor with magnesium powder, and performing heat treatment; s3, nitridation reaction; and S4, carrying out acid etching. According to the YSi2 fine grain reinforced porous silicon-based material provided by the invention, a fine grain strengthening mechanism caused by grain boundary segregation in a structural material is introduced into a silicon negative electrode material, so that the intrinsic strength of the silicon material is improved, pulverization and crack propagation of the material are inhibited, and excellent cycle performance and outstanding rate capability are obtained; the invention provides a novel fine grain reinforced silicon negative electrode model, provides theoretical and experimental guidance for research and development of high-strength and high-specific-energy battery materials, solves the problems of low intrinsic strength, large volume expansion and poor conductivity of the silicon negative electrode material, and has the advantages of simple preparation process, short period, low energy consumption and no carbon, and can be produced on a large scale.

The invention provides a Ziegler-Natta catalyst silicon-magnesium composite carrier and a preparation method thereof, a continuous phase silicon solution is prepared by using a double template agent, the continuous phase silicon solution is mixed with a cross-linking agent and an initiator to obtain a dispersed phase, the dispersed phase is subjected to two-phase speed regulation mixing through a micro-fluidic chip to finally obtain double emulsion droplets, and then operations such as curing, template agent removal and acid etching are performed to obtain the Ziegler-Natta catalyst silicon-magnesium composite carrier. The preparation method comprises the following steps: preparing a spherical silicon dioxide carrier with more excellent performance, then carrying out magnesium source loading and post-treatment, and finally preparing the Ziegler-Natta catalyst silicon-magnesium composite carrier with monodispersity, hierarchical porous structure (micropore-mesopore-macropore), high loading rate and high mechanical strength, and is suitable for industrial-scale polypropylene catalyst production. The prepared catalyst carrier is more perfect in morphology and more uniform in particle size.

The invention relates to the related field of alkaline water electrolysis hydrogen production, in particular to a cobalt manganese oxide catalyst-nonporous anion exchange membrane composite system stable in high-temperature alkaline environment, which comprises a cobalt manganese oxide nanosheet and a quaternized polyarylene ether nitrile nonporous membrane, the metal molar ratio of Co to Mn of the cobalt manganese oxide is 1: 1-3: 1, and the metal molar ratio of the cobalt manganese oxide nanosheet to the quaternized polyarylene ether nitrile nonporous membrane is 1: 1-3: 1. After acid etching, the oxygen vacancy concentration is 0.2-0.5 mmol / g, and the specific surface area is 120-180m < 2 > / g; the quaternization degree of the non-porous membrane is 70-90%, the conductivity at 80 DEG C is greater than or equal to 100mS / cm, and the swelling rate in 10MKOH is 1t; 5%. According to oxygen vacancies (0.2-0.5 mmol / g) and high specific surface area (120-180 m < 2 > / g) formed after cobalt manganese oxide in the composite system is subjected to acid etching, the number of catalytic active sites is remarkably increased, an electronic structure (for example, the ratio of Co < 3 + > is increased) is optimized, the OER overpotential is as low as 210-230 mV under 10 mA / cm < 2 >, the Tafel slope is smaller than or equal to 38 mV / dec, and the charge transfer resistance is smaller than or equal to 20 omega, which are far superior to those of an unetched catalyst and a traditional system; and the water electrolysis oxygen evolution reaction rate is accelerated.

The invention provides a double-dosage-form copper acid etching solution as well as a preparation method and application thereof. The double-dosage-form copper acid etching solution comprises an agent A and an agent B, the agent A comprises the following components in parts by weight: 15-20 parts of an oxidizing agent, 4-7 parts of an organic acid chelating agent, 0.1-0.5 part of inorganic acid, 0.5-2 parts of alkali, 1-2 parts of a surfactant and 0.01-0.1 part of a metal corrosion inhibitor; the agent B is prepared from the following components in parts by weight: 25 to 30 parts of organic acid chelating agent, 0.2 to 0.5 part of inorganic acid, 15 to 20 parts of alkali, 1 to 2 parts of surfactant and 0.1 to 0.3 part of metal corrosion inhibitor. The double-agent copper acid etching solution provided by the invention can be compatible with etching of Cu / Mo and Cu / MTD film layers, can be compatible with etching of film layers with different thicknesses, and is long in service life, low in CD Bias, free of chamfer cracks, good in residue, small in taper variation and short in etching time.

The invention discloses a macrostructure acid etching device and a hot acid etching method, the acid etching device comprises an acid etching tank, the top of the acid etching tank is annularly provided with a water seal tank, and water can be injected or discharged into the water seal tank; the cover plate is rotationally connected with the acid etching tank and is used for sealing the acid etching tank; the acid etching liquid storage device is communicated with the acid etching tank, and the acid etching liquid storage device is used for supplying acid etching liquid into the acid etching tank; and the waste liquid tank is communicated with the acid etching tank. According to the invention, the condensation device, the spraying device and the water seal structure are matched for use, so that acid mist in the acid etching tank can be treated, and zero acid mist emission is realized.

The invention discloses a regulation and control method for a tantalum coating phase based on low-temperature magnetron sputtering and application of the regulation and control method, and belongs to the field of coating preparation. The regulation and control method comprises the following steps: (1) pretreatment: carrying out high-energy bombardment on a matrix material; (2) regulating and controlling the phase of the tantalum coating as a beta phase: depositing an elemental tantalum coating on the surface of the pretreated matrix material; and (3) regulating and controlling the phase of the tantalum coating to be an alpha phase: firstly depositing a base coat on the surface of the pretreated matrix material, and then depositing the elemental tantalum coating. Through the low-temperature magnetron sputtering technology, controllable deposition of the beta phase / alpha phase of the tantalum coating at the temperature of 100 DEG C or below is achieved, the beta phase is obtained without a bottoming layer, the alpha phase is obtained through pure titanium or titanium-tantalum mixed bottoming layer, the alpha phase crystallinity is improved through low-energy interface regulation and control, the titanium-tantalum mixed layer can coordinate the thermal expansion difference, the high binding force of the coating is kept, and therefore the titanium-tantalum composite coating has the good application prospect. The method is suitable for sand blasting and acid etching of the titanium alloy dental implant, low-temperature process compatibility and clinical performance are both considered, and the problems of phase regulation and bonding strength are solved.

The invention discloses a method for leaching waste lithium battery positive electrode powder by using intestinal flora in a neutral environment, and belongs to the technical field of resource recycling, the method comprises the following steps: step 1, a pretreatment link, the pretreatment link comprises the following process links, and each link has no sequence: (1) preparation of battery powder, (2) acquisition of intestinal flora, and (3) preparation of a culture medium; 2, domesticating the flora; and 3, valuable metal in the waste battery powder is leached out. According to the method, the intestinal flora is applied to the biological leaching of the waste LIBs positive electrode powder, so that the dependence of traditional strong acidophilic bacteria on an extremely low pH condition is broken through, and the environmental harm is greatly reduced; according to the method, inorganic acid does not need to be added, the pH value of a reaction system is stabilized within the nearly neutral range of 7.8-8.2, equipment loss caused by acid etching is reduced, reagent consumption for subsequent metal recovery and neutralization treatment is reduced, and remarkable economic benefits and environmental benefits are achieved.

The invention discloses a sialic acid mild brushing acid composition and application thereof, and relates to the technical field of cosmetics. The sialic acid mild brushing acid composition comprises sialic acid and a solvent, the mass concentration of the sialic acid is 2%-15%, and the solvent is selected from at least one of 1, 3-propylene glycol, butanediol, dipropylene glycol and water. The sialic acid is creatively used as one of the mild brushing acid components, can soften old and waste cutin mildly and promote cutin exfoliation and permeation and absorption of the sialic acid, so that the sialic acid can fully play a skin protection role, has an excellent mild cutin exfoliation effect and has the effects of improving hyperpigmentation and coarse pores; and a dynamic balance skin care strategy of breaking while standing and breaking while standing can be realized. The prepared cosmetics have better moisture retention and safety, repair barriers through moisture retention, improve pigmentation through oxidation resistance, stimulate collagen to remodel a supporting structure to improve coarse pores, and finally consolidate the health state of the skin through immunoregulation.

The invention provides a method for preparing electronic-grade copper oxide by using circuit board acidic etching waste liquid, and belongs to the field of copper resource recovery. The method comprises the following steps: sequentially carrying out impurity removal, concentration crystallization, salt-alkali reaction and cleaning on the circuit board acidic etching waste liquid, and collecting to obtain a copper hydroxide crude product; dissolving and recrystallizing to obtain a copper hydroxide refined product; a carbonized ammonia water solution is added to react with the copper hydroxide refined product, and ammonia cupric carbonate is obtained after adsorption and purification; adding a surfactant and a zinc salt additive, and stirring; drying to obtain modified basic cupric carbonate; carrying out selective etching on the modified basic cupric carbonate by adopting dilute acid to obtain basic cupric carbonate particles; and calcining the basic cupric carbonate particles at 300-500 DEG C to obtain the copper oxide powder with the honeycomb structure. According to the method, on the basis of the basic step of recovering copper resources from the circuit board acidic etching waste liquid, the treatment steps of purification, grain refinement, porous etching and the like are added, so that the purity and the activity performance of a final copper oxide product are improved, and the electronic-grade copper oxide is prepared.

The invention discloses an internally-reinforced impact-resistant mica plate which comprises mica plate sheet units arranged in a stacked mode, and a polyphenylene sulfide fiber membrane is arranged between every two adjacent mica plate sheet units. Each mica sheet unit comprises an inner-layer core plate, the inner-layer core plate is a mica sheet, and a reinforced fiber mesh surface and a reinforced mica layer are formed on the upper surface and the lower surface of the inner-layer core plate after surface acid etching; the reinforced mica layer is obtained by forming mica slurry in which inorganic filler and reinforced fibers are uniformly dispersed through hot-pressing curing treatment; and after the reinforced fiber mesh surface is treated by the coupling agent, the resin material which is the same as that in the mica slurry is used for pre-impregnation treatment in advance. According to the composite mica plate, the overall performance and stability of the mica plate are improved, the mechanical strength and impact resistance of the mica plate are remarkably improved, and a more reliable and efficient insulating material is provided for the fields of electrical equipment, aerospace, automobile manufacturing and the like.

A method of treating a surface of a dental implant to impart roughness to the surface is disclosed. The dental implant surface treatment method according to the present invention may comprise: a first surface treatment step for forming regular-pattern grooves in all or a part of the implant surface by means of a laser; and a second surface treatment step of imparting roughness to the grooves and the peripheries of the grooves by acid etching, the first surface treatment step including: a first laser treatment step of processing a plurality of first grooves that are continuous in a first direction and spaced apart in a second direction; and a second laser processing step of processing a plurality of second grooves that are continuous in the second direction and spaced apart in the first direction so as to form a depression at each intersection of the first grooves and the second grooves.

The invention discloses a long-acting stable filling agent for phosphorite mining and a preparation method and application thereof, the long-acting stable filling agent takes cement, slag powder, phosphogypsum and fly ash as matrix components, and is supplemented with additives such as a nano modified liquid, a retarder and an early strength agent. The 3d compressive strength reaches 4.6-5.5 MPa, the 28d compressive strength reaches 13.5-15.5 MPa, the 90d strength retention rate in a simulated acid environment is larger than or equal to 84%, the volume shrinkage rate is smaller than or equal to 0.5%, and the early strength and the excellent long-term acid-resistant stability are both high. Through a synergistic effect of a nano-micron composite structure, pores are filled with nano particles and secondary hydration is promoted, basalt fibers are bridged to resist cracking, and nano montmorillonite blocks acid etching, so that unification of high early strength and long-acting acid resistance is realized. The material is simple and convenient in preparation process, can be efficiently used for mining and filling of phosphorite mountains, and meets the requirements of rapid support and long-term acid medium erosion resistance.

This invention discloses a TiC-Ti3C2T x The preparation method of MXene composite material includes: acid etching of Ti3AlC2 ceramic powder, washing of etching products, centrifugation, and ultrasonic layering to obtain single-layer and few-layer Ti3C2T. x Colloidal solution, then freeze-dried to obtain monolayer and few-layer Ti3C2T x Powder; TiC powder, dried Ti3C2T x TiC-Ti3C2T was prepared by high-shear emulsification and mixing of powder and polytetrafluoroethylene dissolved in anhydrous ethanol, followed by rotary evaporation, drying, and spark plasma sintering. x MXene composite material. This invention solves the problem of reinforcement dispersion in TiC ceramic matrix and addresses the issue of Ti3C2T under high-temperature sintering conditions. x The MXene phase transformation and oxidation problems are addressed, and the TiC matrix is ​​strengthened and toughened by inducing matrix grain refinement, crack deflection, crack bridging, and lamellar pull-out, thereby improving bending strength and fracture toughness.

The invention discloses a titanium dioxide nanorod / dissimilar metal MOFs heterojunction material and a preparation method and application thereof, and belongs to the technical field of photoelectrochemistry seawater hydrogen production. Soluble nickel salt, soluble cadmium salt or soluble cobalt salt and ammonium molybdate are adopted as metal sources, spherical dissimilar metal MOFs grow on the surface of a TiO2 nanorod in situ, and the TiO2 nanorod / dissimilar metal MOFs heterojunction material is prepared. According to the present invention, the oxygen deficiency-regulated dissimilar metal MOFs material (i.e., the titanium dioxide nanorod / dissimilar metal MOFs heterojunction material) is obtained through subsequent acid etching and annealing treatment, the material is subjected to in-situ reconstruction during the OER process to spontaneously form the active hydroxide (NiOOH) of anion protection (MoO4 < 2->), and the excellent stability is represented; only small Faraday efficiency loss (1.2-2.3%) occurs in a high chloride ion environment (3.5 wt%-7wt% of NaCl), and an extensible path is provided for industrial-scale solar hydrogen production by using seawater.

The application discloses a kind of MXene modified polyimide nanofiber composite membranes and its preparation method and application, the method is prepared by acid etching method MXene nanosheet and polyamide acid molecular chain form strong hydrogen bond and coordination effect, significantly enhance interface binding force.MXene effectively transmits load, inhibits crack propagation, substantially improves the tensile strength and toughness of composite membrane, while extending the diffusion path of particulate matter, combined with the electrostatic adsorption effect produced by MXene itself conductivity, significantly improve the interception efficiency of PM0.3~PM2.5 fine particulate matter.The thermal imidization process ensures that PI matrix is completely converted into high-temperature-resistant structure, giving the material the ability to operate stably at high temperature for a long time.The composite membrane realizes four breakthroughs of high strength, high efficiency, low resistance and high dust capacity, providing a new solution for high-performance air filtration under harsh working conditions.

The invention belongs to the technical field of metallurgy and material engineering, and particularly relates to a method for stably and clearly displaying a macrostructure of a cast-rolled aluminum blank based on effective acid etching time. According to the method, the effective acid etching time in the detection of the grain sizes of the macrostructures of different cast-rolled aluminum billet samples under the condition that the acid liquor is repeatedly used is obtained, and the acid etching degree of the cast-rolled aluminum billet can be judged by using the effective acid etching time as a certain acid liquor formula and a certain acid liquor temperature to improve a reliable criterion, so that fixed parameters for stably and clearly displaying the macrostructures of the cast-rolled aluminum billet are obtained. The method has the meanings of improving the repeated use effect of the acid liquor, enhancing the macrostructure image acquisition effect, improving the comparison reliability of the grain size rating result, detecting and manufacturing the automatic intelligence level and the like.

The invention belongs to the technical field of electrocatalytic materials and electrolytic hydrogen production, and particularly relates to a composite electrocatalyst and a preparation method and application thereof. According to the preparation method of the Ni single active center composite electrocatalyst based on the high-rubidium high-silicon lithium ore base as the carrier, uniform loading and efficient activation of the Ni single active center on the ore carrier are achieved through the steps of pretreatment, acid etching activation, lithiation regulation and control, Ni active solution preparation, solvothermal loading, roasting shaping and the like on the high-rubidium high-silicon lithium ore. When the catalyst is applied to urea electrolytic hydrogen production, the catalyst has the advantages of low initial potential, low overpotential and high stability.