100results about How to "Shape is easy to control" patented technology

The invention provides a preparation method and an application method of a gasified slag-based carbon-zeolite composite material, and belongs to the technical field of carbon-zeolite composite materials. The preparation method comprises the following steps: taking gasified slag as a raw material, mixing the gasified slag with alkali, a silicon source substance, a surfactant and water, and sequentially carrying out aging treatment and hydrothermal reaction to obtain the gasified slag-based carbon-zeolite composite material. The gasified slag-based carbon-zeolite composite functional material is prepared from the gasified slag, the process is simple, the preparation cost is low, meanwhile, high-added-value utilization of the gasified slag is achieved, the purpose of treating waste with waste is achieved, and economic benefits and environmental protection benefits are achieved. The gasified slag-based carbon-zeolite composite functional material prepared by the invention has a good removal effect on low-concentration ammonia nitrogen and organic matter wastewater, has regeneration performance, and still has good ammonia nitrogen adsorption and organic pollutant degradation performance after regeneration.

The invention relates to the technical field of catalysts for gas purification, in particular to a hierarchical pore metal-based catalytic adsorbent as well as a preparation method and application thereof. The invention discloses an integrated preparation method combining a sol-gel method and a template method, which comprises the following steps of: adding a template agent before forming gel, adding a proper amount of ammonia water in an aging process, accurately controlling other reaction conditions and a raw material ratio, and controlling a spatial confinement effect of the template method and a chemical reaction in a sol-gel process to obtain a sol-gel composite material. The morphology and size of the catalytic adsorbent can be accurately regulated and controlled, the hierarchical pore metal-based catalytic adsorbent with a microporous structure as a main material and mesopores and macropores as coexistence is finally prepared, the hierarchical pore structure provides rich adsorption sites and catalytic activity centers, and the hierarchical pore metal-based catalytic adsorbent has high adsorption capacity, high selectivity, good catalytic activity, good stability and easy regeneration.

The invention relates to a preparation method of an irradiation-resistant and accident-resistant SiC / SiC nuclear fuel cladding. The preparation method comprises the following steps: (1) alternately carrying out the following step (A) and step (B) from step (A) to step (A) to obtain a tubular SiC fiber preform with at least two PyC interface layers and at least one SiC nanowire interface layer: (A) depositing the PyC interface layers on the surface of the tubular SiC fiber preform through a chemical vapor deposition process; (B) loading a catalyst on the PyC interface layer through vacuum impregnation, and generating a SiC nanowire interface layer on the surface of the PyC interface layer in situ through a chemical vapor deposition process; (2) carrying out densification treatment on the tubular SiC fiber preform by adopting a chemical vapor infiltration process; and (3) depositing a SiC coating on the surface of the tubular SiC fiber preform by adopting a chemical vapor deposition process to obtain the SiC / SiC nuclear fuel cladding tube.

The invention discloses a preparation method and application of a CuBi2O4 film electrode, and belongs to the field of film materials. The preparation method of the CuBi2O4 film electrode comprises the following steps: mixing an aqueous solution of 0.05 mol / L-0. 2 mol / L copper acetate and an aqueous solution of 0.05 mol / L-0. 2 mol / L sodium acetate to obtain an electrolyte I, and obtaining a Cu2O film on FTO (Fluorine-doped Tin Oxide) by adopting an electrodeposition method; adding a coordination agent, KOH and fused salt KNO3 into a 0.05 mol / L-0. 3 mol / L bismuth nitrate solution or adding water to dilute to obtain a solution II; and pulling and dipping the obtained Cu2O film in the solution II, carrying out annealing treatment, washing with deionized water, and drying to obtain the CuBi2O4 film electrode. According to the preparation method disclosed by the invention, Cu2O with uniform surface and good compactness is obtained by regulating and controlling the concentration ratio of cupric acetate to sodium acetate, and the high-quality CuBi2O4 film electrode is prepared by optimizing the concentrations of the coordination agent, the mineralizing agent and the fused salt on the basis.

The utility model relates to a multi-beam laser interference photoetching system which comprises a high-power laser, five high-reflectivity mirrors, two semi-reflecting and semi-transmitting mirrors, three groups of 1 / 2 wave plates and polaroids, thirteen lens supports and a sample table, the high-power laser emits a beam of light, the beam of light is divided into three coherent light beams by the five high-reflectivity mirrors and the two semi-reflecting and semi-transmitting mirrors, and the three coherent light beams are connected with the sample table. The relative positions of the five high-reflectivity mirrors and the two semi-reflecting and semi-transmitting mirrors have a certain corresponding relation with the incident angle and the space angle of the three coherent light beams, the light intensity energy density and the polarization state of the coherent light beams are changed by adjusting the angles of the three groups of 1 / 2 wave plates and the polaroids, and the light intensity energy density and the polarization state of the coherent light beams are changed through the incident angle, the space angle and the polarization state. The period and the morphology of the patterned micro-nano structure are changed, and the characteristic size of the patterned micro-nano structure is changed by changing the light intensity energy density and the polarization state, so that the process is simplified, and the control capability of the patterned micro-nano structure is improved.

The invention relates to a preparation method and application of a hollow nanorod array oxygen evolution electrode, and belongs to the field of hydrogen production by alkaline electrolysis of water. The self-supporting nickel-iron double-metal hydroxide nanosheet coated cobalt hydroxide hollow nanorod array oxygen evolution electrode is obtained through a continuous electro-deposition method; foamed nickel is used as a substrate, and catalytic active components loaded on the substrate are cobalt hydroxide and ferro-nickel double-metal hydroxide; a hollow nanorod structure vertically grows on the surface of the foamed nickel substrate, and the hollow nanorod structure comprises a hollow nanorod-shaped cobalt hydroxide layer located in the hollow nanorod structure and a plurality of layers of nickel-iron double-metal hydroxide nanosheets wrapping the surface of the hollow nanorod-shaped cobalt hydroxide layer; the diameter of the hollow nanorod is 0.2-1 micron, and the length of the hollow nanorod is 2-3 The electrode provided by the invention has unique morphology and good oxygen evolution catalytic activity.

The invention discloses a heat transfer rate control method and device for a graphene liquid drop printing three-dimensional prefabricated body, the heat transfer rate control method is realized by adopting a graphene liquid drop printing three-dimensional prefabricated body device, and the device comprises a printing substrate, a metal enclosing wall, a liftable freezing substrate and a temperature controller, the heat transfer rate control method comprises the steps that the process of printing a three-dimensional prefabricated body is divided into three stages including a low layer, a middle layer and a high layer in sequence according to the number of printing layers, the number of the layers is set to be n1, n2 and n3, and in the layer-by-layer printing process, the temperature of a liftable freezing base plate, the temperature of a metal enclosure and the height of the liftable freezing base plate in each stage are controlled, the control of the ice crystal growth heat transfer rate in the process of printing the three-dimensional preform is realized, and the stability of the ice crystal growth rate is ensured, so that the three-dimensional connected graphene material with uniform axial microstructure and excellent performance is prepared.

The utility model provides a testing device for a train brake pad friction block texture structure, belongs to the technical field of brake pad friction blocks, and aims to solve the stick-slip vibration phenomenon occurring when a high-speed train is braked. In the prior art, a large number of tests and debugging are needed and wide popularization is difficult to realize when the stick-slip vibration is inhibited by integrally changing the property of a friction block or installing a viscoelastic damper and the like. In the utility model, different textures are designed on the surface of the brake pad friction block; the surface texture design based on the friction blocks is adopted to restrain the stick-slip vibration phenomenon of the train braking system, the method is a method for actively restraining the stick-slip vibration from the source, the structure of the braking system does not need to be modified or increased or decreased, and therefore the operation and maintenance cost of a train is not increased, and popularization is easier to achieve.

The invention belongs to the technical field of nano material preparation, and particularly discloses a preparation method of a manganese-cobalt-doped cerium dioxide nanorod, which comprises the following specific steps: 1) dissolving cerium salt, manganese salt and cobalt salt in distilled water to obtain a solution A; 2) dissolving an alkaline precipitator in distilled water to obtain a solution B; 3) dropwise adding the solution A into the solution B under sufficient stirring, and then transferring the mixed solution into a hydrothermal synthesis kettle for sealing; and 4) after the reaction is finished, cooling, washing and drying, and then roasting at high temperature in an air atmosphere to obtain the manganese-cobalt doped cerium dioxide nanorod material. The preparation method comprises the following steps: preparing a precursor of a manganese-cobalt-cerium composite oxide through a one-step hydrothermal synthesis method by modulating the types of a cerium salt, a manganese salt, a cobalt salt and an alkaline precipitator, and then washing, drying and roasting to obtain the manganese-cobalt-doped cerium dioxide nanorod with a regular morphology and a cubic fluorite structure. The method disclosed by the invention is simple in preparation condition, high in operation safety, green and environment-friendly, and convenient for industrial production.

The invention discloses a waste lithium battery electrode recycling and regenerating method which comprises the following steps: (1) crushing a waste lithium battery electrode and carrying out acid leaching with sulfuric acid, hydrochloric acid or phosphoric acid to obtain an acid leaching solution; (2) adding 1.2-2.0 equivalent weight of iron powder into the pickle liquor according to the molar weight of copper ions in the pickle liquor under the protection of inert gas, reacting for not less than 30 minutes, adjusting the pH value to 1.5-2.0 by using ammonia water, and filtering to obtain a first impurity-removed solution; (3) adding not less than 0.05% of an antioxidant into the first impurity-removed solution by mass, adjusting the pH value to 2.6-3.5 by using ammonia water, and filtering to obtain a second impurity-removed solution; and (4) adding a manganese-containing composition into the second impurity-removed solution, and heating to 90-100 DEG C, so that ferrous ions are separated out in the form of lithium manganese iron phosphate double salt, and the precipitate is the regenerated electrode material. Impurities in the electrode are removed and recycled in a non-oxidation mode, the technological process is shortened, high-temperature and high-pressure conditions are not needed, and the preparation process is milder.

The invention relates to a method for forming an ordered intermetallic compound on the surface of a shape-controllable core-shell structure and application, and the method comprises the following steps: depositing an alloy component on the surface of a palladium seed through a seed mediation method to obtain platinum-based core-shell nanoparticles, loading the platinum-based core-shell nanoparticles on a carrier, and then carrying out negative-pressure short-time heat treatment at 350-450 DEG C to obtain shape-maintained core-shell particles with ordered surfaces; the metal components in the alloy are selected from at least one of Fe, Co or Cu and Pt. Compared with the prior art, the method has the advantages that the metal components form the ordered phase on the surfaces of the particles through surface component evolution in a mild heat treatment mode under the low-temperature condition under the condition that the original special morphology and structure of the particles are not sacrificed, the morphology loss of the nanoparticles under high-temperature heat treatment can be effectively avoided, and the performance of the nanoparticles is improved. The particle size is increased due to agglomeration and Ostwald ripening. Meanwhile, compared with original particles, the obtained Pt-based core-shell particles with controllable morphology and ordered surfaces have enhanced activity and stability.

The invention discloses a method for preparing neodymium iron boron magnetic powder by a chemical method, which comprises the following steps of: 1, mixing iron salt, an organic ligand and a solvent for coordination reaction to obtain an iron-based metal organic framework material; 2, dipping the iron-based metal organic framework material in the rare earth-fused salt mixed solution, and drying to obtain a dipping precursor; step 3, carrying out calcination and reduction reaction on the impregnated precursor to obtain a rare earth-iron precursor; and 4, mixing the rare earth-iron precursor with a reducing agent, and carrying out a reduction diffusion reaction. According to the method, an iron-based metal organic framework material is used as an iron source and a template, a dipping process is combined, a highly uniform and dispersed dipping precursor is obtained, the refined spherical neodymium iron boron magnetic powder is obtained through calcination, hydrogen reduction and a reduction diffusion reaction, and the magnetic powder is controllable in component and high in magnetic conductivity. The method is suitable for preparing the neodymium-iron-boron magnet with excellent magnetic performance and adjusting the composition and grain boundary distribution of the neodymium-iron-boron magnet.

The invention discloses a preparation method of a platinum-based lanthanum cobaltate catalyst for NO oxidation, and belongs to the field of catalytic chemistry and environmental chemistry. The preparation method comprises the following steps: loading PtMn bimetallic nanoparticles on a lanthanum cobaltate carrier, and treating by a hydrothermal technology to obtain a PtMn / LaCoO3-air and steam catalyst and a PtMn / LaCoO3-nitrogen and steam catalyst. The preparation method comprises the following steps: simultaneously reducing platinum acetylacetonate and dimanganese decacarbonyl by adopting an oil phase reduction method to form PtMn bimetallic nanoparticles, and loading the PtMn nanoparticles on the lanthanum cobaltate carrier by adopting an impregnation method. The loaded catalyst is placed in a tubular furnace and roasted for 8 h at the temperature of 650 DEG C in the atmosphere of H2O-containing air or nitrogen, the catalyst is formed, and the obtained catalyst contains richer active oxygen species, shows good catalytic activity on NO oxidation under the low-temperature condition and has good application prospects in the field of motor vehicle tail gas pollution control.

The invention provides composite silver soldering paste and a preparation method and application thereof.The preparation method comprises the following steps that silver nitrate and PVP are dissolved in an ethylene glycol solution, and stirring is conducted for 20-45 min through a constant-temperature magnetic stirrer at the temperature of 45-75 DEG C; adding a certain amount of HCl into the mixed solution, magnetically stirring for 15-30 minutes, and cooling to room temperature; putting the mixture into a reaction kettle, and performing vacuum constant-temperature heating for 150-200min at 100-190 DEG C; and after washing with deionized water and absolute ethyl alcohol, carrying out ultrasonic treatment to obtain the composite silver soldering paste. According to the multi-scale composite silver soldering paste, an ethylene glycol reduction method is adopted, silver ions in a solution are reduced into silver atoms, submicron or micron particles are secondarily grown on the basis of nano-silver particles, and the multi-scale composite silver soldering paste is prepared and has better electrical and mechanical properties; the multi-scale silver particles are easy to generate, the reaction conditions are easy to control, the preparation method is simple, safe and environmentally friendly, the needed raw material types are few, the number of devices is small, few organic matter is added, and the nano-silver particles controllable in morphology and size are easy to obtain.

The invention belongs to the technical field of electrochemical sensor functional materials. The invention particularly relates to a preparation method of a nitrogen-doped three-dimensional porous carbon-loaded petal-shaped molybdenum disulfide composite material, an obtained product and application. The nitrogen-doped three-dimensional porous carbon-loaded petal-shaped molybdenum disulfide composite material provided by the invention is a porous material and comprises the elements of C, N, S and Mo. The nitrogen-doped three-dimensional porous carbon has a multilevel porous three-dimensional network structure, Mo and S elements are loaded on the surface and inside the nitrogen-doped three-dimensional porous carbon, and the nitrogen-doped three-dimensional porous carbon mainly exists in the form of a MoS2 compound and is of a petal-shaped structure. Wherein strong metal-carrier interaction exists between the nitrogen-doped three-dimensional porous carbon and the MoS2. The nitrogen-doped three-dimensional porous carbon provided by the invention has a large specific surface area and excellent conductivity, so that the conductivity of the prepared composite material is improved, and the stacking problem of MoS2 is avoided. The generation of the petal-shaped MoS2 nanosheets is beneficial to shortening of a transfer route and promotion of rapid transmission and diffusion of electron ions. The strong metal-carrier interaction between the nitrogen-doped three-dimensional porous carbon and MoS2 can provide charge transfer, enhance the electro-catalytic performance, and facilitate electro-catalysis and distinguishing of electroactive biological micromolecules dopamine and uric acid.

The application belongs to the technical field of optical materials, and particularly discloses a synthesis method of core-shell quantum dots based on surface activation, which comprises the following steps: S1, preparing a quantum dot core; S2, degassing reaction is carried out on zinc precursor, octadecene and oleylamine in proportion, then the quantum dot core obtained in S1 is injected, a metal alkyl compound is added, and the temperature is increased to 230-250 DEG C; S3, the shell precursor is injected for 3-4 times, the temperature is increased at the same time, the inner shell is grown, zinc stearate and TOP-S are injected again, the ZnS shell is grown, and the InP core-shell quantum dots with regular morphology are obtained. The synthesis method of core-shell quantum dots based on surface activation is adopted, the quantum dots with controllable morphology and size distribution are obtained, the method is suitable for industrial production, and has wide applicability.

This invention discloses a samarium-lanthanum co-doped calcium oxyborate yttrium nonlinear optical crystal material, its preparation method, and its applications. The samarium-lanthanum co-doped calcium oxyborate yttrium nonlinear optical crystal material belongs to the monoclinic crystal system, has a space group of Cm, and a chemical formula of Sm. 0.3 La 0.1 :Y 0.6 Ca4O(BO3)3 has a second harmonic response intensity of 0.89 × KDP, and exhibits transmittance exceeding 80% in the 500–1000 nm and 1600–2400 nm wavelength ranges. It also has a strong absorption peak in the 1000–1600 nm wavelength range. Therefore, the samarium-lanthanum co-doped calcium oxyborate yttrium nonlinear optical crystal can be considered as a nonlinear optical crystal material with broad application prospects in the field of optics.

The utility model discloses plastic material production equipment, relates to the technical field of positive and negative electrode material preparation equipment, and aims to solve the problem of structural regulation and control of the conventional positive and negative electrode material preparation. Comprising a box body and a cylinder body, the box body is communicated with the cylinder body through an adapter, and heating assemblies for heating the interiors of the box body and the cylinder body are arranged on the box body and the cylinder body; a feeding port communicated with the interior of the box body is formed in the box body, a conveying belt is further arranged in the box body, the conveying belt is driven by a conveying motor, a roller column is further arranged in the box body, the roller column is of a composite structure, and the roller column is arranged above the conveying belt and rolls materials on the conveying belt. The two ends of the cylinder body are rotationally connected with the adapter and the discharging port respectively, the cylinder body is driven by the driving mechanism, the discharging port is formed in the supporting seat, and an inner wall threaded groove is formed in the inner wall of the cylinder body. And meanwhile, the productivity is also improved.

The invention belongs to the technical field of synthesis and preparation of aluminum nitride, and discloses a controllable and extensible preparation method of a one-dimensional aluminum nitride nanowire / nanotube, which comprises the following steps: (1) uniformly mixing a solid aluminum source and a solid nitrogen source, transferring the mixture into a rotatable crucible, transferring the crucible into a tubular furnace, sealing the tubular furnace, and carrying out heat preservation for 2-3 hours; vacuumizing and then introducing protective gas; (2) under the condition that protective gas is continuously introduced, the tubular furnace is heated to a preset target temperature for a nitridation reaction, and the nitridation reaction is carried out under the condition that a crucible rotates at a constant rotating speed; and after the reaction is finished, cooling the tubular furnace and stopping the rotation of the crucible to obtain a one-dimensional aluminum nitride nanowire or nanotube product. According to the method, the solid aluminum source and the solid nitrogen source are used as raw materials, and the crucible rotation is introduced during the nitridation reaction to carry out dynamic enabling improvement, so that the single-crystal aluminum nitride nanowire or nanotube with high purity and uniform morphology can be efficiently synthesized.

This invention discloses high-entropy rare-earth silicate ceramic nanopowders, their preparation methods, and applications. The preparation method of the high-entropy rare-earth silicate ceramic nanopowders of this invention includes the following steps: 1) dissolving rare-earth oxide powder in an acid solution to prepare a rare-earth salt solution, then adding urea and silica powder and performing a gelation reaction to obtain a gel; 2) igniting the gel for combustion synthesis, grinding, and obtaining a precursor powder; 3) calcining the precursor powder to obtain the high-entropy rare-earth silicate ceramic nanopowders. The high-entropy rare-earth silicate ceramic nanopowders of this invention possess excellent characteristics such as fine particle size, uniform elemental distribution, large component space, and absence of impurities. Furthermore, its preparation method has advantages such as fast synthesis speed, simple equipment, simple and controllable process, and low industrialization cost, making it suitable for application in hot-end components of aerospace engines and possessing very broad application prospects.

This invention provides a method for forming interdigitated electrodes, wherein the interdigitated electrodes are metal stacks. The method includes: providing a piezoelectric substrate; forming a metal material stack and a composite mask material layer on the piezoelectric substrate; the metal material stack includes a first metal material layer and a second metal material layer; the composite mask material layer includes a first mask material layer and a second mask material layer made of different materials; patterning the composite mask material layer to obtain a composite mask layer; the composite mask layer includes a first mask layer corresponding to the first mask material layer and a second mask layer corresponding to the second mask material layer; etching the first metal material layer using the composite mask layer as a mask to obtain a first metal layer, simultaneously consuming the first mask layer; and etching the second metal material layer using the second mask layer as a mask to obtain a second metal layer. This invention solves the problem that the interdigitated electrode material needs to be coated with a thick photoresist, and the unexpected reduction in photoresist thickness during the etching process makes it difficult to control the morphology of the interdigitated electrodes.

The invention relates to the technical field of solid oxide fuel cells, in particular to a solid oxide fuel cell electrolyte with a rotary honeycomb structure as well as preparation and application of the solid oxide fuel cell electrolyte. The solid oxide fuel cell electrolyte with the rotary honeycomb structure is obtained by rotating the solid oxide fuel cell electrolyte with the honeycomb structure along x, y and z three-direction center points as original points; wherein the rotation angle ranges from 15 degrees to 90 degrees. According to the invention, the specific surface area is increased by rotating the honeycomb structure, and the volume is not changed because the sum of three normal stresses is zero during rotation, so that the surface area-volume ratio of the electrolyte of the battery is effectively improved, and the active area of reaction with reaction gas is increased; the production cost is reduced, the development of the mobile portable application field is promoted, and the defects in the prior art are overcome.

The application discloses high-entropy rare earth silicate ceramic nano powder and a preparation method and application thereof. The preparation method of the high-entropy rare earth silicate ceramic nano powder comprises the following steps: 1) dissolving rare earth oxide powder in an acid solution to prepare a rare earth salt solution; 2) mixing the rare earth salt solution and a sodium silicate solution, adding ammonia water to perform chemical co-precipitation, then performing standing and aging, and then taking the precipitate to perform drying to obtain a precursor powder; and 3) placing the precursor powder under the condition that the temperature is 1100 DEG C to 1200 DEG C to perform calcination. The high-entropy rare earth silicate ceramic nano powder has excellent characteristics such as small particle size, uniform element distribution, large component space and no impurity phase, and the preparation method has the advantages of low synthesis temperature, simple equipment, simple and controllable process, low industrialization cost and the like, is suitable for being used on a hot end part of an aerospace engine and has a very wide application prospect.

The invention relates to a VOx nanoring for a lithium ion battery negative electrode material, a preparation method of the VOx nanoring, the lithium battery negative electrode material and a lithium battery. The preparation method comprises the following steps: S100, preparing raw materials: preparing sodium orthovanadate and thioacetamide; s200, mixing the raw materials to obtain a mixed solution; s300, carrying out heating reaction to generate turbid liquid with a stable nanometer annular structure; and S400, cooling and separating, namely taking out the turbid liquid in the high-pressure kettle, cooling to room temperature, separating by a centrifugal machine, cleaning and drying to obtain the dry nanoring capable of being used for the lithium battery negative electrode material. The preparation method disclosed by the invention is convenient, simple, good in repeatability, high in yield and capable of realizing large-scale production and industrialization. The prepared nanoring structure can be kept stable for a long time, the size and morphology of the nanoring are controllable, and the morphology can be regulated and controlled through the reaction time, the reaction temperature, the reactant ratio and the like.

The present invention discloses a method for preparing a double-network nanocellulose microgel-based porous material, the method comprising the following steps: (1) preparing a double-network nanocellulose microgel using carboxyl nanocellulose, aldehyde nanocellulose and an EDC / NHS mixed solution; (2) preparing a Pickering emulsion gel; and (3) freeze-drying the Pickering emulsion gel to obtain a nanocellulose microgel-based porous material. The method of the present invention has simple process and strong operability. The prepared nanocellulose microgel-based porous material has the characteristics of multi-level pore structure, controllable pore size distribution and pore morphology, and has excellent interface stability and mechanical properties, good biocompatibility, and has broad application prospects in multiple fields such as filtration adsorption, energy storage and sound absorption, energy dissipation buffering, chemical sensors, and controlled release of drugs.

The invention discloses an ultrathin porous nickel hydroxide nanosheet supercapacitor electrode material and a preparation method and application thereof, and belongs to the technical field of capacitor electrode materials. According to the material, an amorphous alloy serves as a core layer to play a self-supporting role, nano-porous nickel layers on the two sides provide a nickel source for in-situ growth of nickel hydroxide, and mutually-crossed ultrathin porous nickel hydroxide on the outermost layer serves as an active substance and vertically grows on the surface of the nano-porous nickel in situ; the diameter of the ultrathin porous nickel hydroxide is 0.5-2 mu m, the thickness of the ultrathin porous nickel hydroxide is 2-10 nm, and the size of holes in the nanosheet is 5-8 nm. The preparation method of the material has the advantages that the operation is simple, the cost is low, high temperature and use of nickel salt are not needed, the repeatability is good, and Ni (OH) 2 grows on nano porous nickel in situ and is a self-current-collector electrode material.

The application provides a self-supporting Ni-Fe-Mn oxygen evolution electrocatalyst and a preparation method thereof, and belongs to the technical field of catalytic material preparation. The Ni, Fe and Mn metal raw materials are repeatedly smelted, and after smelting, suction casting is carried out to obtain a cast plate. The cast plate is subjected to homogenization treatment, and then is cut and polished. Finally, etching is carried out in a nitric acid solution to obtain the self-supporting Ni-Fe-Mn oxygen evolution electrocatalyst. The self-supporting electrocatalyst is prepared by the method of arc smelting, heat treatment and chemical etching, and has the advantages of simple preparation process, easy industrialization, adjustable size, excellent stability and excellent OER performance.

The invention provides an aerogel-porous carbon sphere composite material as well as a preparation method and application thereof. The composite material comprises porous carbon spheres, sodium polyacrylate aerogel and polyvinyl alcohol aerogel, adjacent porous carbon spheres are connected through the sodium polyacrylate aerogel and the polyvinyl alcohol aerogel, pores are formed between the adjacent porous carbon spheres, the porous carbon spheres mainly comprise garden balsam seed carbon spheres, semen cuscutae carbon spheres, fried mustard seed carbon spheres and semen lepidii carbon spheres, the sodium polyacrylate aerogel is mainly prepared from p-benzene dicarboxylate and sodium polyacrylate as raw materials, and the polyvinyl alcohol aerogel is mainly prepared from metal salt and polyvinyl alcohol as raw materials. The specific surface area of the composite material is 200-500 m < 2 > / g, the pore volume is 0.08-0.185 cm < 3 > / g, the average pore size is 7-10.5 nm, and the composite material has high physical adsorption and chemical adsorption performance on environment smoke components such as nicotine and 3-vinylpyridine and can be used as an adsorption material of nicotine and 3-vinylpyridine.

This invention belongs to the field of environmental protection and resource recycling technology, specifically relating to a method for preparing high-purity basic magnesium carbonate from low-grade magnesite. The method includes the following steps: S1, crushing the low-grade magnesite and mixing it with an acid solution for acid leaching to obtain an acid leaching solution; S2, removing impurities from the acid leaching solution to obtain a refined solution; S3, absorbing the carbon dioxide gas released during the acid leaching step using an absorbent to obtain a carbon dioxide-loaded solution; S4, mixing the refined solution and the carbon dioxide-loaded solution for precipitation to obtain basic magnesium carbonate product and a protonated absorbent solution; S5, recovering the acid and regenerating the absorbent solution from the protonated absorbent solution using a bipolar membrane electrodialysis device. This invention utilizes the CO2-loaded solution as a precipitant to react with the Mg in the refined solution. 2+ The reaction produces basic magnesium carbonate. The reaction conditions are mild, and the crystal morphology and particle size are easy to control, thus obtaining a high-value-added product that meets market demands.

The invention discloses a lanthanum ion doped oxygen calcium yttrium borate nonlinear optical crystal material and a preparation method thereof, the lanthanum ion doped oxygen calcium yttrium borate nonlinear optical crystal material belongs to a monoclinic system, the space group is Cm, the chemical formula is La0.1: Y0. 9Ca4O (BO3) 3, the frequency multiplication coefficient is 2 * KDP, the ultraviolet cut-off edge is less than 200 nm, and no absorption peak with the intensity greater than or equal to 0.2 cm <-1 > exists in the range of 200-2500 nm. Therefore, the lanthanum ion doped yttrium calcium oxide borate crystal can be used as a nonlinear optical material with a wide application prospect in the field of optical parameter chirped pulse amplification.