37results about How to "Reduce interfacial energy" patented technology

The invention belongs to the technical field of phase-change materials, and particularly relates to a long-term stable supercooling solar phase-change heat storage material capable of controlling electric trigger heat emission and a preparation method of the long-term stable supercooling solar phase-change heat storage material. The phase change heat storage material is composed of hydrogel serving as a framework material, hydrated salt fixed in a hydrogel framework through physical and chemical connection, a stably dispersed photo-thermal agent and an electrode embedded in the material. According to the invention, the spontaneous fluctuating effect of hydrated salt is obviously inhibited to reach a critical dimension and trigger crystallization, the long-term stable supercooled state of the material in a wide temperature range is realized, and by adjusting the proportion of the components, not only is the phase separation of the material effectively prevented, but also the photo-thermal conversion efficiency of the material can be obviously improved.

The present invention discloses a method for repairing concrete cracks at low temperature, its application and a concrete crack repairing agent, which belongs to the technical field of on-site processing of building materials and repair of existing buildings. In the method for repairing concrete cracks at low temperature of this scheme, a repairing agent with a low-temperature early strength agent of a string-stool-type structure component is used. The low-temperature early strength agent of the string-stool-type structure component is obtained by first subjecting the string-stool-type structure main chain obtained by ring-opening polymerization to an alkali-catalyzed reaction to obtain an incompletely condensed string-stool-type structure, and then reacting with the monomers to substitution-catalysis-copolymerization and substitution-ATRP reaction. This scheme can reduce the viscosity of the repair material by adding a low-temperature early strength agent of a string-stool-type structure component to the repair material, improve its early strength, fast hardening and adaptability, and is particularly suitable for repairing concrete cracks in a low-temperature environment. The repair material has simple components and good compatibility with concrete at the crack, and can effectively solve the problems of poor adaptability, high viscosity and low strength of the repair material, and has broad prospects for promotion and application.

The invention discloses a lithium iron manganese phosphate positive electrode material, a preparation method thereof and application of the lithium iron manganese phosphate positive electrode material in a solid-state battery, and relates to the technical field of lithium iron manganese phosphate positive electrode materials. According to the preparation method disclosed by the invention, graphene oxide is grafted by adopting polyethylene glycol, a chain transfer agent 2-methyl-2-[(dodecylthio-carbonyl) sulfur] propionic acid is linked on the graphene oxide, and then N-isopropylacrylamide is polymerized on the graphene oxide through azodiisobutyronitrile; the N-isopropylacrylamide simultaneously contains a hydrophobic group isopropyl group and a hydrophilic group acylamino group, so that the graphene oxide is converted into amphiphilic graphene oxide; hydrophilic groups or lipophilic groups on the material are directionally arranged in a solution, so that the interface energy of the material can be reduced, the dispersity of the material is improved, and the material plays an important role in regulating and controlling the size and morphology of particles, on one hand, side chains of the material are adsorbed on the surface of the material in a crystal nucleus growth process, and crystal nucleus orientation can be induced; on the other hand, through a space formed by layer-by-layer assembly between graphene, a crystal nucleus grows in the assembly space.

The invention discloses a silicide connection layer forming method and a semiconductor device, and the method comprises the steps: providing a semiconductor structure which is made of silicon; forming a protective layer on the semiconductor structure and forming a metal layer on the protective layer; performing an annealing process so that metal particles in the metal layer pass through the protective layer and react with silicon in the semiconductor structure to form an intermediate layer; removing the remaining part of the metal layer under the condition that the protective layer protects the intermediate layer; the annealing process is performed again so that the intermediate layer continues to react with the silicon in the semiconductor structure to form a silicide connection layer, and the protection layer is removed. In the process of removing the residual part of the metal layer, the middle layer is not damaged due to the protection of the protection layer, and the performance of the semiconductor device is improved.

The invention discloses a method for preparing a self-flowing high-efficiency fast-dissolving drag-reducing fracturing fluid system. The following components in weight percentage are added into a reactor in sequence: 45% to 50% of the water-soluble high molecular polymer solution obtained in step one, 27% to 29% of the fluorine-containing monomer modifier solution obtained in step two, 11% to 12% of the polymer nanocomposite material obtained in step four, 2% to 3% of a dispersant, 1.8% to 1.9% of an inorganic salt, 1.2% to 1.3% of a cross-linking agent, and the balance is water. The invention discloses a method for preparing a self-flowing high-efficiency fast-dissolving drag-reducing fracturing fluid system. By adding a modifier into a nano material, a polymer film can be directly formed on the surface of the nano material by chemical bonding, thereby changing the surface properties thereof, so that the stability and shear resistance of the fracturing fluid are maintained at high temperatures.

The invention relates to an oiling agent for chemical fiber spinning and a preparation method and application of the oiling agent. The oiling agent comprises novel oligomeric potassium alkyl sulfate, a nonionic surfactant, an emulsifier, solvent oil and water. The emulsion formed by dissolving the novel oligomeric alkyl sulfate potassium salt oil agent in water has excellent stability, and does not have obvious phase separation phenomena such as sinking and floating after standing at room temperature for 56h. When the oiling agent for chemical fiber spinning disclosed by the invention is applied to the field of chemical fiber production, chemical fibers can be endowed with excellent antistatic property and smoothness, so that the spinnability of the chemical fibers is better; and the oiling agent belongs to a green phosphorus-free formula, so that the spinnability index of chemical fibers is guaranteed, and the pollution of discharged water to the environment is reduced.

The invention provides a nano-composite anti-seepage coating for goaf sealing and a preparation method and application thereof. The impermeable coating comprises the following components in percentage by mass: 10 to 30 percent of nano silica sol subjected to surface organic modification, 15 to 35 percent of styrene-butadiene latex subjected to pH buffer stabilization, 0.5 to 10 percent of functional nano material subjected to surface activation treatment, 20 to 60 percent of superfine sand and the balance of short fiber, inorganic powder filler and auxiliaries. The method comprises raw material pretreatment; step-by-step gradient blending is performed; and functions are compounded. According to the application, the nano-composite anti-seepage coating is applied to surrounding rock reinforcement, crack plugging or anti-seepage sealing engineering of a coal mine goaf. The slurry has the advantages of being high in deep infiltration capacity, excellent in surface film forming and internal compatibility and stable in performance, an internal infiltration reinforcing layer and a surface sealing layer can be formed at the same time after construction, and an integrated double-layer anti-seepage network is formed.

The invention belongs to the technical field of nano materials, and particularly relates to a water dispersible ceramide product as well as a preparation method and a preparation system thereof, and the water dispersible ceramide product is prepared by mixing a ceramide phase, a water phase and an additive phase. The invention also provides a preparation method of the water-dispersible ceramide product. According to the preparation method, the water-dispersible nano ceramide is continuously produced through continuous flow; meanwhile, adding phase feeding nodes are arranged, adding phases are increased or decreased at any time according to production requirements, and produced products are adjusted in real time; the process is simple in preparation process, does not need high pressure, is flexible in production, and can modulate products according to production tasks at any time.

The application relates to the technical field of materials for generators, and provides a preparation method of an elastic material for a wind turbine generator set slip ring support, which comprises the following steps: after amino-terminated polydimethylsiloxane is dissolved in an organic solvent, diisocyanate is slowly added dropwise, a disulfide bond chain extender is added after reaction, and the temperature is increased to continue the reaction, so that amino-terminated polydimethylsiloxane elastomers containing dynamic disulfide bonds are obtained; after the elastomers prepared above are dissolved in an organic solvent, 4,4'-diamino diphenyl disulfide and trimellitic anhydride are added, and PDMS prepolymers are obtained after reaction; after polyimide monomers are dissolved in an organic solvent, the monomers are added into the PDMS prepolymers prepared above in batches, and then the temperature is increased in stages to react for a period of time, and the temperature is cooled to room temperature, so that the elastic material is obtained; the elastic material can still maintain sufficient toughness and anti-vibration capacity in a low-temperature environment, the risk of breakage is reduced, and the operation reliability of the wind turbine generator set in a severe cold region is improved.

The invention relates to the technical field of cells, in particular to a solar cell and a preparation method thereof, and the preparation method comprises the following steps: adding a hole transport material and a first perovskite material into a solvent to prepare a mixed solution; coating a substrate with the mixed solution, and performing annealing treatment to obtain a composite hole transport layer; coating the composite hole transport layer with a perovskite precursor solution, and performing annealing treatment to obtain a perovskite layer; the perovskite precursor solution comprises a second perovskite material, and the second perovskite material is the same as the first perovskite material. According to the preparation method of the solar cell provided by the invention, the perovskite seed crystal with the same components as the perovskite layer is pre-buried in the composite hole transport layer, and the perovskite seed crystal is used as a nucleation site to induce the perovskite layer to crystallize from bottom to top, so that the generation of bottom holes is inhibited.

The invention discloses a WS2 / W composite material, a preparation method thereof and application of the WS2 / W composite material in a sodium-sulfur battery. The preparation method comprises the following steps: uniformly stirring isopropanol and acetone to obtain a mixed solution A; weighing tungsten hexachloride, adding the tungsten hexachloride into the mixed solution A, and uniformly stirring to obtain a mixed solution B; transferring into a reaction kettle, sealing and putting into a drying oven for reaction; after the reaction is finished, carrying out suction filtration and washing on a product by using industrial alcohol, and drying in a vacuum oven to obtain W18O49 powder; the method comprises the following steps: weighing W18O49 powder and sublimed sulfur, respectively and correspondingly placing the W18O49 powder and sublimed sulfur in a first porcelain boat and a second porcelain boat, then placing the second porcelain boat in the first porcelain boat, placing the second porcelain boat in a tubular furnace, introducing argon into a furnace chamber of the tubular furnace, after the pressure of the furnace chamber is increased to 0.2-0.3 MPa, keeping the airtightness of the system, heating to 1100-1300 DEG C at the rate of 20 DEG C / min, keeping the pressure at 0.2-0.3 MPa in the heating process, and keeping the temperature for 2-3 hours; and after the temperature reaches 1100-1300 DEG C, continuously preserving heat for 2 hours, introducing argon, cooling to room temperature, and collecting to obtain WS2 / W powder. The problems of poor conductivity of the sulfur positive electrode, polysulfide shuttle effect and slow reaction kinetics are solved.

The invention provides a heat treatment method for a directionally solidified high-carbon nickel-based composite material, and belongs to the technical field of heat treatment of nickel-based composite materials. The high-carbon nickel-based composite material is a carbide and gamma'phase complex-phase reinforced high-temperature structural material, a coarse primary gamma 'phase in a structure is dissolved by controlling parameters of solution treatment, conditions are created for uniform precipitation of a secondary gamma' phase, meanwhile, the carbide at a grain boundary is converted, and the M6C carbide is precipitated at the grain boundary; the morphology and size of a secondary gamma'phase and carbide are regulated and controlled through aging treatment, so that the gamma 'phase has high interface stability, the strengthening effect of the gamma' phase is improved, and meanwhile, M23C6 carbide separated out in the aging treatment process is distributed in a fine and discrete point shape; and secondary gamma'phase and carbide separated out after heat treatment can hinder dislocation motion, inhibit grain boundary slippage and greatly improve the mechanical property of the nickel-based composite material.

The invention relates to an aluminum alloy soldering lug and a preparation method and application thereof, and belongs to the technical field of welding. The aluminum alloy soldering lug disclosed by the invention is prepared from the following elements in percentage by mass: 3.0 percent to 4.5 percent of Si, 2.0 percent to 3.5 percent of Fe, 0.8 percent to 1.2 percent of Mg, 0.10 percent to 0.25 percent of Zr, 0.05 percent to 0.15 percent of Sc, 0.02 percent to 0.08 percent of Er, 0.05 percent to 0.12 percent of Ti, 0.005 percent to 0.02 percent of B and the balance of Al and other inevitable impurities. The mass ratio of (Zr + Sc) / Fe is 0.08 to 0.15; the mass ratio of Mg to Si is 0.25 to 0.35; the mass ratio of (Fe + Si) to (Zr + Sc + Er) is 20-25; the problems that laser welding aluminum alloy is thick in weld joint structure and uneven in performance, and a dissimilar material welding interface is embrittled are fundamentally solved.

The invention discloses a preparation method of a reforming hydrogen dechlorinating agent, which comprises the following steps: (1) drying petroleum coke, mixing with alkaline earth metal peroxide, and pretreating; (2) mixing the mixture pretreated in the step (1) with alkali, performing high-temperature treatment under an inert atmosphere condition, washing and drying; and (3) carrying out oxidation modification, washing and drying on the dried product obtained in the step (2) to obtain the dechlorinating agent. By adopting the dechlorinating agent disclosed by the invention, the content of chloride in reformed hydrogen can be reduced to 0.5 mg / L or below, and the dechlorinating agent has relatively high breakthrough chlorine capacity.

The invention discloses a high-strength and high-plasticity rare earth magnesium alloy deformed material and a preparation method thereof, and the high-strength and high-plasticity rare earth magnesium alloy deformed material comprises the following components in percentage by mass: 5.0%-6.5% of Gd, 1.5%-2.4% of Y, 1.0%-2.2% of Zn, 0.3%-0.45% of Zr, 5.0%-7.0% of Er and the balance of Mg. The method for preparing the high-strength and high-plasticity magnesium alloy deformation material comprises the steps of alloy smelting, solution treatment, multidirectional free forging and aging treatment, and finally, the yield strength of the high-strength and high-plasticity rare earth magnesium alloy ranges from 398 MPa to 402 MPa, the tensile strength ranges from 441 MPa to 453 MPa, and the ductility ranges from 15.8% to 17.2%. According to the method, part of Gd elements in the Mg-Gd series alloy with the high Gd content are replaced with Er elements, and the elongation of the Mg-Gd series alloy is greatly improved on the basis that the strength of the Mg-Gd series alloy is basically kept unchanged through solid solution strengthening of Er, aging precipitation promotion and c / a value reduction.

The invention relates to the technical field of rubber modification, in particular to a fluororubber-ethylene propylene diene monomer compatilizer and application. Silica (DMSN) with a dendritic mesoporous structure is synthesized and can be physically located at a two-phase interface, the effects of anchoring and reinforcing the phase interface are achieved, the size of a phase region is prevented from being too large, and therefore the compatibility is preliminarily improved. PFTS is further used for carrying out surface grafting modification on DMSN, PFTS is grafted to the surface of silicon dioxide through Si-O-Si, the compatibility of a perfluoro long chain at the other end and an FKM phase is good, and the interface bonding force between the filler and a rubber matrix is remarkably enhanced. The finally obtained composite material not only has the inherent high temperature resistance, oil resistance and chemical resistance of FKM, but also improves the low temperature resistance due to the introduction of EPDM, and greatly enhances the mechanical strength and toughness due to the enhancement of PFTS-DMSN.

The application discloses a kind of photovoltaic welding band and preparation method thereof, belong to photovoltaic material technical field.The method includes: in-situ chemical reduction preparation silver coating five silver nanometer reinforcing agent, silver nanoparticle uniform load forms core-shell structure;Ultrasonic-assisted smelting Sn-Bi-Ag-Cu quaternary solder master alloy;Copper band microetching forms Ra0.35-0.55 μm porous structure;Silane bridging hot-dip plating, control solder layer thickness 18-22 μm, staged cooling.Compared with prior art, the welding band tensile strength of the application is improved, the solder joint shear force is improved, the wet heat aging retention rate is in high position, the interface hole rate is reduced, the reliability and welding performance are significantly improved, and is suitable for high-efficiency photovoltaic module.

The invention discloses a functional electrolyte, the electrolyte comprises a zinc salt and a solvent, and the solvent comprises water and D-galactose (D-Gal). The molar concentration of the D-Gal in the solution is 0 to 0.5 M. The mixed electrolyte is formed by adding a proper amount of D-Gal, the pH of a negative electrode interface is stabilized, the stability of a zinc negative electrode is effectively improved, the coulombic efficiency of the battery is high, and the cost is low. Under the conditions of 1.0 mA cm <-2 > and 1.0 mAh cm <-2 >, the cycle life of the ZnZn symmetric battery can reach 2600 hours. Even under the high current density of 10mA cm <-2 >, stable operation can be carried out for 900 hours. When the ZnZVO battery is paired with a ZVO cathode, the capacity retention ratio is stabilized at 62.78% after 1500 times of circulation under the condition of 1.0 A g <-1 >.

The present application relates to a lightweight piston and a preparation method, comprising the following steps: S1 vacuum smelting: an aluminum-based alloy is placed in a vacuum induction smelting furnace, a vacuum degree is less than or equal to 10 ‑2 Pa, a smelting temperature is 730-770 DEG C, and a smelting time is 30-60 minutes; the present application uniformly disperses nanocrystals and modified graphene in a melt through process scale, pulse ultrasonic and ultrasonic-electromagnetic synergistic treatment, avoids the agglomeration problem of traditional external particles, reduces the interface energy of the seed and the aluminum matrix at the atomic scale through the doping of carbon and boron, provides dispersion strengthening and heterogeneous nucleation at the nanometer scale through titanium diboride and titanium carbide seeds, provides interface optimization and high-temperature pinning through a molybdenum tungsten shell layer, provides self-lubrication and heat conduction channels at the submicron scale through modified graphene, provides skeleton reinforcement at the micron scale through a three-dimensional network structure, and provides plasticity through a refined aluminum matrix.

The application discloses an aluminum-magnesium-silicon alloy matrix carbon nanotube reinforced composite and a hot extrusion preparation method thereof, and belongs to the field of metal matrix composite manufacturing. The method aims to solve the problems of reinforcement phase agglomeration, interface reaction to generate brittle Al4C3 phase and unstable forming quality. The steps include: acidizing and ultrasonic dispersion pretreatment of multi-walled carbon nanotubes; mixing the dispersion liquid with aluminum-magnesium-silicon alloy powder and performing high-energy ball milling to form a core-shell structure composite powder; cold pressing to form a preform; hot extrusion forming under the conditions of a temperature of 400 to 500 DEG C, an extrusion ratio of 10:1 to 25:1, a speed of 1 to 10 mm / s and online quenching, followed by solid solution aging heat treatment. The application realizes uniform dispersion distribution of carbon nanotubes through chemical and physical cooperative pretreatment and mechanical ball milling, effectively inhibits the generation of interface brittle Al4C3 phase by using a low-temperature large deformation process, and significantly improves the interface bonding quality and matrix density. The prepared composite has a hardness of 150 HV or more, and excellent mechanical properties and wear resistance.

The invention discloses a water-based acrylic emulsified asphalt anticorrosive paint, a preparation method of the anticorrosive paint and a preparation method of a water-based acrylic emulsion, and belongs to the technical field of anticorrosive paints.The water-based acrylic emulsified asphalt anticorrosive paint comprises anionic emulsified asphalt, the water-based acrylic emulsion and the like. The anionic emulsifier is used in the water-based acrylic emulsion, so that the hydrophilic group of the anionic emulsifier can interact with the carboxyl of the acrylic monomer, for example, hydrogen bonds or ion pairs are formed, and the interaction is beneficial to better adsorption of the anionic emulsifier on the surface of the acrylic monomer; the waterborne acrylic emulsion and the anionic emulsified asphalt with extremely weak polarity have very good compatibility, and the interface energy between the anionic emulsified asphalt and the waterborne acrylic emulsion can be effectively reduced, so that the acrylic anticorrosive coating has good corrosion resistance when being stored for a long time, and the corrosion resistance of the coating is improved. And the acrylic emulsion and the emulsified asphalt are not layered.

The invention belongs to the field of protective coatings, and particularly discloses a thermal barrier coating surface modification method which comprises the following steps: sequentially forming an alloy layer and an aluminum layer on the surface of a thermal barrier coating to obtain a thermal barrier coating containing a modified coating; the thermal barrier coating containing the modified coating is subjected to heat treatment; the alloy layer contains aluminum and rare earth elements. According to the surface modification method of the thermal barrier coating, rare earth elements are introduced into the alloy layer, so that the in-situ reaction activity of the alloy layer and the surface of the thermal barrier coating is improved, a large number of Al3Zr intermediates with fine and uniform crystal grains are generated in the alloy layer, the interface energy caused by the in-situ reaction is reduced, complete coating is formed on the surface of the thermal barrier coating, and the surface of the thermal barrier coating is improved. And the CMAS corrosion resistance of the coating is obviously improved. In addition, surface modification is simple and easy to operate, and the method is suitable for large-scale popularization and application.

The invention provides a preparation method of cubic microcrystalline copper powder, the cubic microcrystalline copper powder and application of the cubic microcrystalline copper powder, and particularly relates to the technical field of functional powder preparation. The preparation method comprises the following steps: adding a first copper salt solution into a reducing agent solution at a speed of 2-5L / min to carry out a first reduction reaction so as to obtain a mixed solution; and continuously adding a second copper salt solution into the mixed solution according to the speed of 0.2-1L / min to carry out a second reduction reaction, and finally carrying out solid-liquid separation, washing and drying to obtain the cubic microcrystalline copper powder, wherein the reducing agent solution comprises a reducing agent, a template agent and water. The preparation method provided by the invention is simple in process, a distribution process of the copper salt solution is adopted, the growth trend of particles is effectively controlled, and the cubic microcrystalline copper powder with good dispersity and uniform particle size distribution is obtained.

The invention relates to a casting method for refining an alloy phase in a hypereutectic aluminum alloy, and relates to the technical field of cast aluminum alloys, and the casting method comprises the following steps: preparing the hypereutectic aluminum alloy which comprises the following components in percentage by mass: 18.5-19% of silicon, 4.6-5.2% of copper, 0.35-0.45% of magnesium, 4.24-4.28% of nickel, 0.01-0.05% of phosphorus and the balance of aluminum and inevitable impurities; smelting is conducted according to the nominal components, and molten aluminum alloy liquid is obtained; a grain refiner is added into the molten aluminum alloy liquid, heating and stirring are conducted, ultrasonic treatment is conducted, and the treated aluminum alloy liquid is obtained; a refining agent and a refining solution are added into the treated aluminum alloy liquid, cooling is carried out, stirring and ultrasonic treatment are carried out while adding is carried out, argon is introduced to remove impurities, and the refined aluminum alloy liquid is obtained; and scooping out oxide skin on the surface of the refined alloy liquid, and pouring to obtain the hypereutectic aluminum alloy. The hypereutectic aluminum alloy has the effect of refining the alloy phase in the hypereutectic aluminum alloy, and the mechanical property and the thermal property of the hypereutectic aluminum alloy can be effectively improved.

The application belongs to the technical field of polymer materials, and particularly relates to a high-strength and high-toughness polyamide composite material and a preparation method thereof. The composite material comprises the following components in parts by weight: 80-100 parts of long-chain semi-aromatic polyamide, 20-30 parts of oxidized carbon fiber, 10-20 parts of toughening agent, 5-10 parts of ethylene-acrylic acid ionomer, 1-3 parts of pentaerythritol-based polyol, and 1-6 parts of processing aid. The application adds a certain amount of ethylene-acrylic acid ionomer and pentaerythritol-based polyol in a long-chain semi-aromatic polyamide-oxidized carbon fiber reinforced system. During the melt blending process, the two modifiers of ethylene-acrylic acid ionomer and pentaerythritol-based polyol form an active layer rich in polar functional groups on the surface of the oxidized carbon fiber, improve the interfacial interaction between the polyamide and the filler, and solve the problem that the strength and toughness of the polyamide composite material in the prior art are difficult to be considered simultaneously.

This application discloses a dispersant for lithium-ion battery negative electrode slurry and its application. The dispersant comprises water and an active ingredient, with the mass ratio of the active ingredient to water being 1:(0.7-6). The active ingredient comprises a first component, a second component, and a third component, with the mass ratio of the first, second, and third components being (0.1-4):(0.1-3):(0.1-4). The first component is polystyrene sulfonic acid or lithium polystyrene sulfonate; the second component is a comb-type copolymer polycarboxylic acid or a comb-type copolymer lithium carboxylic acid; and the third component is an acrylic acid-maleic anhydride copolymer or an acrylic acid-maleic anhydride copolymer lithium salt. The dispersant for lithium-ion battery negative electrode slurry provided in this application can solve the problem of difficult dispersion of carbon black and graphite in slurry.

The application relates to high-sphericity nano tetragonal barium titanate for MLCCs and a preparation method thereof. The technical scheme is as follows: a titanium source, a dissolving agent and potassium perchlorate are mixed to obtain mixed material A; the mixed material A is heated twice under air condition, is preserved, is naturally cooled to obtain a reaction product; the reaction product is washed with distilled water I, is separated, is dried to obtain titanium dioxide powder; the titanium dioxide powder and barium oxide are mixed to obtain mixed material B; the mixed material B, ethylene glycol, pure water and an anionic surfactant are mixed to obtain a mixed solution; the mixed solution is moved to a polytetrafluoroethylene reaction kettle, is placed in a microwave heating furnace, is heated, is preserved, is naturally cooled and is filtered; the filtered product is washed with distilled water II, is separated, is dried to obtain high-sphericity nano tetragonal barium titanate for MLCCs. The product prepared by the application has high purity, high sphericity, small particle size, good dispersity and high tetragonality.

The invention belongs to the technical field of high polymer materials, and particularly relates to a polyurethane emulsion as well as a preparation method and application thereof. The polyurethane emulsion is prepared from the following raw materials in parts by weight: 35 to 50 parts of polyisocyanate, 50 to 70 parts of polyol, 3 to 5 parts of a chain extender, 1 to 2 parts of a neutralizing agent, 200 to 300 parts of water, 10 to 20 parts of an organic solvent, 0.01 to 0.05 part of a catalyst and 3 to 5 parts of functionalized aluminum oxide nanoparticles. According to the invention, the modified aluminum oxide nanoparticles are used as a functional additive of the waterborne polyurethane emulsion, so that the storage stability of the waterborne polyurethane emulsion can be remarkably improved, and the drying process of the waterborne polyurethane emulsion can be accelerated through the temperature response characteristic of the modified aluminum oxide nanoparticles, so that the polyurethane emulsion shows more excellent performance in application; the problem that the drying rate of the waterborne polyurethane emulsion is reduced due to the fact that the storage stability of the waterborne polyurethane emulsion is improved by enhancing the hydrophilicity of polyurethane in the prior art is successfully solved.

The invention discloses a probe card substrate preparation method, which comprises: S1, placing spinel powder and calcium titanate powder in a high-energy ball mill, carrying out ball milling, and drying to obtain mixed powder; s2, pressing the mixed powder into a green body with a required shape, and sintering to form a composite green ceramic chip; s3, grinding, polishing and punching the composite green ceramic chip; and S4, coating photoresist on the punched composite green ceramic chip, and carrying out hot drying, exposure, development and cleaning to obtain the probe card substrate. By compounding spinel and calcium titanate, similar symmetry is achieved, atoms and ions at an interface can easily obtain a stable arrangement mode with the lowest energy, the stability of the composite interface is improved, the stability of a dielectric constant is kept, and dielectric loss is reduced; therefore, the prepared probe card substrate has high resistance to interference of electromagnetic waves, so that the prepared probe card substrate has excellent low dielectric loss and anti-electromagnetic interference capability.

The application belongs to the technical field of high-temperature-resistant aluminum alloy, and discloses a high-temperature-resistant aluminum alloy, a preparation method and application thereof. The high-temperature-resistant aluminum alloy contains Mg with a weight ratio of 0.03% to 0.08%, Sc with a weight ratio of 0.15% to 0.25%, Zr with a weight ratio of 0.10% to 0.20%, 8% to 9% of composite rare earth Ce+La, Fe and Cu as impurities with a content of less than 0.01%, and the rest is Al. The high-temperature-resistant aluminum alloy contains a main strengthening system of Al3(Sc,Zr) nano composite phase and Ce-La multi-element rare earth phase, a simplified component system, only a small amount of Mg, Sc, Zr and composite rare earth, strictly limited Fe, Cu and elements with a content of less than 0.01%, excellent high-temperature-resistant performance and excellent toughness.