56results about How to "Uniform shape" patented technology

The invention discloses high-purity oxamide with concentrated particle size and spherical morphology, a preparation method of the high-purity oxamide and application of the high-purity oxamide in preparation of a slow-release fertilizer, and belongs to the technical field of oxamide synthesis and application. The method comprises the following steps: mixing an ammonia-alcohol solution and an alcohol ester solution, conveying the mixed solution into a series tubular reactor for reaction, and then conveying the mixed solution into a parallel tubular reactor for reaction after pressure stabilization and flow equalization to obtain a reaction solution containing oxamide; performing flash evaporation on the reaction liquid to obtain flash evaporation liquid and flash evaporation gas, and performing solid-liquid separation on the flash evaporation liquid to obtain solid oxamide and filtrate; and drying the solid oxamide to obtain the oxamide. The method realizes high conversion rate and high purity, and the product has ultrafine particle size distribution. The purity of the prepared oxamide is greater than or equal to 99%, the D50 particle size is concentrated to 50 + / -15 microns, the spherical morphology is uniform, the release is stable, and the oxamide has a very good effect in preparation of long-acting slow-release fertilizers and combustion inhibitors and research on the nitrogen utilization rate.

The invention discloses a formula and a preparation method of a glutinous rice sausage. The preparation method comprises the following steps: stir-frying glutinous rice and salted meat; the stir-fried glutinous rice comprises glutinous rice, fried lard oil, minced garlic, trehalose, refined salt and monosodium glutamate; the salted meat comprises pork, chopped salted fat dices, water, white granulated sugar, refined salt, monosodium glutamate, sodium tripolyphosphate, sodium pyrophosphate and auxiliary materials; the preparation of the stir-fried glutinous rice comprises hot frying and cold frying. The flavor of the glutinous rice sausages is remarkably improved, the glutinous rice in the sausages absorbs grease of the stuffing, particles are full, the taste is fragrant, sweet, soft and glutinous, and the overall flavor is richer and more harmonious.

The utility model discloses a manual bread cutting machine, which relates to the technical field of manual bread making equipment and comprises a mounting base and a mounting handle rotatably connected in the mounting base, and the mounting handle is rotatably connected with two mutually symmetrical transmission plates; according to the bread cutting device, the multiple cutting knife frames are distributed in the length direction of the mounting frame in a linear array mode, bread can be cut into multiple parts through one-time operation, and compared with a traditional mode that the bread is broken through fingers or a common bread cutting tool is used, the cutting efficiency is improved, the batch cutting requirement is met, and manpower and time cost is reduced. And on the other hand, the cutting knife frames distributed in an array mode guarantee the consistency of the cutting effect, the cut bread is uniform in shape and size, and follow-up dish making and presenting are facilitated. The design solves the problem that a common bread cutting tool is difficult to ensure the consistency and stability of the cutting effect, and avoids the influence on the dish quality due to different shapes and sizes of bread.

The application discloses a novel proton battery positive electrode material and a preparation method thereof. Iron source solution and phosphorus source solution are respectively prepared through an organic solution, and then the two solutions are mixed to perform a solvothermal reaction. After that, the product obtained in the reaction is washed and dried to obtain the novel proton battery positive electrode material. The material can be used to prepare a proton battery positive electrode sheet. The novel proton battery positive electrode material prepared by the application is a nanoparticle, the main component of which is iron phosphate. The particle morphology is uniform, and the specific surface area is large. The size of the particle is 50.0-200.0 nm. The proton battery prepared by using the novel proton battery positive electrode material has good electrochemical performance. The preparation method provided by the application is simple in process, raw materials are easy to obtain, and is suitable for large-scale industrial production.

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.

The invention belongs to the technical field of advanced powder material preparation, and particularly relates to a micron-sized metal powder preparation system which comprises a raw material system, a gas supply system and an atomization tower. The atomizing tower comprises an atomizing chamber, a liquid drop collector is arranged at the bottom end of the atomizing chamber, and a reaction kettle is arranged below the liquid drop collector; a micro-mixer and an atomizing device are arranged in the atomizing chamber, the micro-mixer comprises a sol generating unit and a liquid drop generating unit, an inlet of the sol generating unit is connected with a raw material system, an outlet of the sol generating unit is connected with an inlet of the liquid drop generating unit, and an outlet of the liquid drop generating unit is connected with an outlet of the atomizing device. An outlet of the liquid drop generation unit is connected with an inlet of the atomization device, the liquid drop generation unit is further provided with a first gas inlet, and the first gas inlet is connected with a gas supply system. The preparation system provided by the invention realizes accurate control of powder components, morphology and size, and has the advantages of low cost, uniform size, continuous production and the like.

A kind of metal pipe fitting electromagnetic forming device and method based on laser heating, with positioning system including positioner, first guide rail, first numerical control moving platform, for accurately positioning metal pipe fitting and mold coordinates;Conveying system includes second guide rail, numerical control moving platform, motor, for realizing the rotation and movement of metal pipe fitting;Heating system includes laser heating device, temperature detector;Electromagnetic forming system includes spiral tube coil, mold, capacitor, DC power supply and control switch;Its characterized in that, motor, fixture, metal pipe fitting, mold, spiral tube coil are horizontally distributed on the same axis, metal pipe fitting can be rotated with the help of motor, and can be moved in the gap between spiral tube coil and mold with the aid of conveying system.The present application can realize uniform heating when metal pipe fitting electromagnetic warm forming, greatly improve heating efficiency, reduce heat affected zone, and improve the position accuracy of metal pipe fitting local microstructure electromagnetic forming.

The present application relates to a kind of preparation method and application of metal phthalocyanine-graphite phase carbon nitride / graphene ternary composite material, it solves the problem of poor dispersibility, easy aggregation and poor conductivity of metal phthalocyanine material as electrocatalyst.Existing Preparation method steps include: metal phthalocyanine, graphite phase carbon nitride are added to sulfuric acid, after heating stirring, solution A is prepared by cooling;Solution B is prepared by stirring after adding sodium nitrite to solution A under ice bath;Graphene oxide is ultrasonically dispersed in distilled water to prepare solution C;Solution B is added dropwise to solution C and stirred, then ascorbic acid is added and stirred, the product is centrifuged, washed and dried to prepare metal phthalocyanine-graphite phase carbon nitride / graphene ternary composite material.The ternary composite material prepared by the method is a two-dimensional sheet structure, has high dispersibility, large specific surface area, good conductivity and structural stability;The product of the present application can be used for electrocatalytic reduction of carbon dioxide.

The invention relates to amino acid modified red-mud-based magnesium-iron-aluminum hydrotalcite and a preparation method and application thereof.The preparation method comprises the following steps that red mud and inorganic acid are mixed and heated and leached under the stirring condition, an obtained leaching product is subjected to solid-liquid separation, and upper-layer acid leaching liquid containing iron and aluminum and residues are obtained; mixing the obtained upper-layer acid leaching solution with amino acid to obtain a mixed solution; adding magnesium salt into the obtained mixed solution, and carrying out coprecipitation reaction to obtain turbid liquid; and centrifuging, washing and drying the obtained turbid liquid to obtain the amino acid modified red mud-based magnesium-iron-aluminum hydrotalcite. Iron and aluminum elements in the red mud are directly extracted, the cost is reduced, and meanwhile the performance and the additional value of the hydrotalcite product prepared from the red mud are remarkably improved; amino acid molecules are introduced, the crystallinity, the specific surface area and the adsorption capacity of the magnesium-iron-aluminum hydrotalcite are improved, a co-precipitation reaction is adopted, the reaction temperature is low, the reaction time is short, and the prepared amino acid modified red-mud-based magnesium-iron-aluminum hydrotalcite can be used for treating phosphorus-containing wastewater.

This invention discloses a continuous crystallization apparatus and preparation method for ultrafine ammonium perchlorate. The apparatus consists of a mixing unit, an ultrasonic enhancement unit, a gas-liquid Taylor flow control unit, and a post-processing unit. The preparation method combines solution reaction crystallization, ultrasonic-enhanced mixing, and gas-liquid Taylor flow microscale control. It utilizes the confined space within the Taylor flow liquid section to control crystal growth, providing a uniform and stable growth environment for crystal growth. This effectively avoids the problem of wide crystal particle size distribution caused by uneven supersaturation and wide residence time distribution in traditional stirred crystallizers. It achieves continuous and controllable crystallization of ultrafine ammonium perchlorate, overcomes the defects of wide particle size distribution in traditional methods, and can prepare ultrafine ammonium perchlorate crystals with narrow particle size distribution and small average particle size. It has the advantages of simple and efficient process and high product quality.

The utility model discloses a novel flowmeter device which comprises an upper shell and a lower shell which are assembled with each other, rotors are rotationally installed in the upper shell and the lower shell, a liquid outlet pipe and a liquid inlet pipe are arranged at the outer end of the upper shell and the outer end of the lower shell respectively, a plurality of blades are distributed on the outer sides of the rotors at equal intervals, and columns are arranged on the blades. Each blade is provided with a cylinder, so that the shape of each blade is kept uniform, the weight of each blade is balanced, and the dynamic balance effect is improved. The pressing block and the sinking groove are arranged in a long and short manner, so that the problem of reverse installation can be avoided; and the assembling groove and the aligning block are uniquely positioned and matched, so that the problem of reverse assembly is further avoided. The two ends of the rotor are modified into flat-corner cone blocks, and top sharp corners of the cone blocks are removed, so that the injection molding rate is increased, and damage caused by collision is avoided.

The utility model provides a continuous rolling and forming tea leaf processing device, which relates to the technical field of tea leaf processing and comprises a working barrel, a discharging screen drum is coaxially connected in the working barrel, a rolling assembly is connected in the discharging screen drum and comprises a temperature controller and a plurality of layers of rolling disc groups, protrusions and grooves are formed in the outer circle of the multi-layer rolling disc set. The tea rolling device solves the problems that in the prior art, the tea rolling forming effect is not stable, and the application range is limited.

This invention discloses a laser welding device for the rim and spokes of thin-walled wheel hubs, relating to the field of wheel hub manufacturing technology. It includes a welding unit and a welding positioner. The welding unit comprises a welding robot and a oscillating laser welding head, the oscillating laser welding head being fixedly connected to the end effector of the welding robot's arm. The welding positioner includes a base, a tilting seat, a tilting drive device, a hollow turntable, and a rotation drive device. The tilting drive device drives the tilting seat to tilt, and the rotation drive device drives the hollow turntable to rotate. The hollow turntable has mounting holes for the rim and positioning fixtures for the spokes of the thin-walled wheel hub. This invention uses laser welding to replace traditional gas shielded welding, combining welding torch oscillation and workpiece displacement, effectively avoiding the burn-through problem when welding thin-walled wheel rims. It achieves high-quality, high-precision, and high-efficiency automated welding of the rim and spokes, meeting the urgent need for lightweight manufacturing of agricultural machinery wheel hubs.

The application discloses a preparation method of SiC powder, and comprises the following steps: firstly, mixing silicon powder with a purity of 9N and carbon powder to obtain a precursor; and rapidly heating the sample by taking the Joule heat of the powder sample as a heat source to obtain high-purity SiC powder. The non-equilibrium reaction state generated by the ultrafast heating, cooling rate and short-time holding reduces the reaction energy barrier of the conversion of the silicon powder and the carbon powder into SiC, promotes the generation of high-value high-purity SiC products, and the products can be applied to various fields such as chip semiconductors, wear-resistant ceramics and new energy. The preparation method has the advantages that the SiC prepared by the rapid thermal shock technology has high purity and stable structure, the preparation method is simple, the material cost is greatly reduced, the SiC can be mass-produced, the production efficiency is improved, and the energy consumption is reduced.

This invention relates to the field of copper material preparation technology, specifically a control method for a continuous extrusion apparatus for wide-width hollow copper profiles. Based on the cross-sectional characteristics of the target wide-width hollow copper profile, the method collaboratively sets the rotational speed of the dual extrusion rollers, the feed rate of multiple billets, and the temperatures of the expansion cavity and the forming die. Driven by the dual extrusion rollers, the copper billets undergo plastic deformation within the expansion cavity and achieve lateral convergence to form a metal cavity with a predetermined hydrostatic pressure. By monitoring the weld interface state of the metal cavity and the profile exit shape, real-time feedback signals are obtained. The flow channel contour of the expansion cavity and the sizing zone of the forming die are then collaboratively optimized and controlled to obtain a corresponding set of process control parameters. These parameters are then evaluated and corrected by an offline expert system until the preset requirements are met. This invention fundamentally ensures the complete metallurgical bonding of the internal welds during the continuous extrusion process of wide-width hollow copper profiles, improving the mechanical properties and density of the wide-width hollow copper profiles.

This invention discloses a manual argon arc welding method for sealing welds of containers with metal gaskets, aiming to solve the problems of multiple filler layers, poor welding quality, and slow speed in existing technologies. The method includes butt welding of base materials, attaching a metal gasket to the base material, with a bottom gap of 1-2 mm formed by the butt welding; using tungsten inert gas (TIG) welding to weld the base material and metal gasket together in one pass at both included angles to form the weld seam. During welding, the welding torch current is 180-220 A, the arc length is controlled within 2 mm, the welding speed is 20-22 cm / min, and two weld layers are formed. This invention is suitable for welding butt welds of sealed containers with metal gaskets, achieving the effects of fewer weld layers, high welding quality, and high speed.

This invention discloses a near-infrared fluorescent silicon dot, its preparation method, and its application in antibacterial and tumor treatment. The silicon dot is generated via a one-step hydrothermal method through a high-temperature condensation reaction between the carboxyl group of a 4-carboxyporphyrin dye and the amino group of a silane coupling agent. The silicon dot synthesized in this invention exhibits excellent water dispersibility, high near-infrared fluorescence intensity and pH stability, uniform morphology, good photostability, good biocompatibility, and high reactive oxygen species (ROS) yield. Furthermore, the preparation method is simple and convenient, uses widely available raw materials, and is low-cost, making it suitable for industrial production. Based on these excellent properties, it can be used to prepare fluorescent probes as fluorescent markers for cell and biological imaging. Its excellent singlet oxygen generation performance can be used for photodynamic therapy against bacteria and tumors. In addition, the silicon dot also possesses peroxidase properties, catalyzing the generation of hydroxyl radicals from hydrogen peroxide, thus enabling its use in chemokinetic therapy.

The invention discloses a lead thiophosphate composite nitrogen-doped carbon porous microsphere material as well as a preparation method and application thereof, and belongs to the technical field of electrochemical energy storage materials. The preparation method of the lead thiophosphate composite nitrogen-doped carbon porous microsphere material comprises the following steps: dissolving a lead salt in an organic solvent, dissolving 2-methylimidazole in water, mixing the two solutions, carrying out solvothermal reaction, separating out a product, and reacting with a gas-phase sulfur source and a phosphorus source under the protection of inert gas to obtain the lead thiophosphate composite nitrogen-doped carbon porous microsphere material. The lead thiophosphate composite nitrogen-doped carbon porous microsphere composite material is obtained. According to the invention, a metal organic framework template method and a chemical vapor deposition method are ingeniously combined, and a brand new path for controllably preparing the lead thiophosphate composite nitrogen-doped carbon porous microsphere material is provided. When the prepared lead thiophosphate composite nitrogen-doped carbon porous microsphere material is used as a sodium ion battery negative electrode, a porous microsphere negative electrode formed by compounding lead thiophosphate and nitrogen-doped carbon shows remarkably improved electrochemical performance.

The utility model discloses a single-die BFS device which comprises a main die, a head die and vacuum channels facilitating vacuumizing treatment, a plurality of bottle body forming cavities used for forming bottle bodies are formed in the main die, and a plurality of head die forming cavities and at least two vacuum channels which are independently arranged are formed in the head die. A plurality of vacuumizing holes are formed in the bottle body forming cavity and / or the head mold forming cavity, each vacuumizing hole in the bottle body forming cavity is connected with one vacuum channel, and each vacuumizing hole in the head mold forming cavity is connected with the other vacuum channel. According to the single-mold BFS device disclosed by the utility model, at least more than two vacuum channels which are independent from each other are arranged, so that different areas in the mold can be vacuumized independently, the vacuum degrees required by different areas of an ampoule bottle can reach the standard, and the forming effect is good; the multiple vacuumizing holes are formed to be connected with the vacuum channel for vacuumizing, so that vacuumizing in the same area is more uniform, and the forming consistency is high.

This invention discloses a method for preparing nano-cobalt phosphate and its application, belonging to the field of new energy technology. The preparation method provided by this invention includes the following steps: S1. A cobalt salt solution, a phosphorus source solution, and a pH adjuster are simultaneously introduced into a stirred base liquid; the base liquid is water; the concentration of the cobalt salt solution is 1–3 mol / L; during the simultaneous introduction process, the pH of the resulting mixture is controlled to be 8–10, and the temperature is controlled to be 20–40℃; S2. The solid product obtained in step S1 is calcined. The preparation method provided by this invention can prepare nano-cobalt phosphate with relatively uniform particle size and pure composition at a mild temperature without the use of thickeners or other additives. This invention also provides applications of the above preparation method.

The utility model discloses coating equipment for PVC (polyvinyl chloride) coated fabric production, which relates to the field of textile processing equipment and comprises a supporting bottom plate, a supporting top plate is arranged above the supporting bottom plate, control devices are symmetrically arranged on two sides of the supporting bottom plate, a center mounting frame is arranged at the bottom of the supporting top plate, and a plurality of control devices are symmetrically arranged on the center mounting frame. A plurality of liquid spraying plates are arranged at the bottom of the center mounting frame, and liquid conveying pipelines matched with the liquid spraying plates are arranged at the top of the center mounting frame. Cloth is preheated through the heating frame, and the adhesion effect and stability of follow-up spraying can be guaranteed; the cleaning roller cleans the surface of the cloth at the cloth inlet end, the covering effect of a cloth coating can be ensured, the cloth is preheated through the heating frame, and the adhesion effect and stability of subsequent spraying can be ensured; and the cleaning roller cleans the surface of the cloth at the cloth inlet end, so that the covering effect of a cloth coating can be ensured.

The invention relates to a titanium silicalite molecular sieve, a preparation method thereof and a method for preparing epoxypropane, and the method comprises the following steps: S1, mixing titanium silicalite molecular sieve raw powder, a first main binder, water, an optional first binder and an optional first surfactant, and carrying out first molding to obtain titanium silicalite molecular sieve microspheres; s2, mixing the titanium silicalite molecular sieve microspheres, a second binder, water and an optional second surfactant, and carrying out secondary molding to obtain a titanium silicalite molecular sieve precursor; s3, performing steam aging on the titanium silicalite molecular sieve precursor to obtain a titanium silicalite molecular sieve pre-product; and S4, carrying out roasting treatment on the titanium silicalite molecular sieve pre-product. The titanium silicalite molecular sieve prepared by the method disclosed by the invention has a porous structure and high mechanical strength, is used for propylene epoxidation reaction, and can obtain relatively high raw material conversion rate and target product selectivity.

This invention relates to the field of molecular sieve technology, specifically to a SAPO-34 molecular sieve, its preparation method, and its applications. The preparation method includes: aging, pre-crystallization, and crystallization of a gel containing an aluminum source, tetraethylammonium hydroxide, a silicon source, a phosphorus source, and water; wherein the aging temperature is 40-80℃, and the aging time is 4-12 h; the pre-crystallization temperature is 90-130℃, and the pre-crystallization time is 2-24 h; and the crystallization temperature is 180-210℃, and the crystallization time is 24-50 h. The SAPO-34 molecular sieve prepared by this invention has a nanometer-sized particle size, uniform morphology, clean surface, high regularity, and the preparation operation is simple and environmentally friendly.

This disclosure belongs to the field of cell culture technology, and specifically relates to a serum-free culture medium for MSCs and its preparation method. The culture medium contains a fixed ratio of basic nutrients and six key regulatory factors, namely transferrin, ascorbic acid, human serum albumin, human fibroblast growth factor rhFGF, platelet-derived growth factor PDGF-BB, and transforming growth factor TGF-β1. By optimizing the combination and concentration of these six key regulatory factors, the proliferation rate and activity of MSCs are significantly improved. It also provides four suitable formulations: high proliferation, high activity, balanced, and economical. The culture effect is stable and reproducible, with high safety and a simple process, making it suitable for laboratory research and large-scale clinical-grade MSC culture.

This invention discloses a Bi@Ce-UiO-66-Br catalyst and its photocatalytic reduction of CO. 2 In this application, the catalyst is prepared by a solvothermal method using a ligand-functionalized Ce-based metal-organic framework (Ce-UiO-66-Br), followed by in-situ reduction encapsulation to confine and encapsulate metallic Bi within Ce-UiO-66-Br, forming a core-shell structured photocatalyst. The Ce-UiO-66-Br shell provides spatial confinement and dispersion stability for the metallic Bi, while the Bi core and the Ce-UiO-66-Br shell produce a synergistic catalytic effect, precisely controlling CO2 emissions. 2 The reduction reaction pathway directs the reaction to produce CH4. 4 The catalyst of this invention has a simple and highly controllable preparation process, and the resulting catalyst has a stable structure. It also exhibits photocatalytic CO2 production under simulated sunlight. 2 Reduction of CH 4 The selectivity is nearly 90%, and the photocatalytic stability is excellent; this catalyst can be directly applied to gas / liquid phase photocatalytic CO2 production. 2 The reducing system is CO. 2 Highly selective conversion of CH 4 It provides highly efficient core materials, which have both academic research value and industrial application prospects.

The invention provides a manufacturing method of an MIM capacitor, and is applied to the technical field of semiconductors. According to the method, the bottom metal layer is formed through multiple film forming processes, and the temperature of the substrate is reduced to the preset value in the gaps of the film forming processes, so that the average temperature of the substrate in the forming process is reduced and is ensured to be lower than 270 DEG C, and the growth of metal grains in the bottom metal layer is inhibited. And meanwhile, in the process of forming the bottom metal layer, at least one of the deposition speed, the deposition power and the deposition vacuum degree of the film forming process is reduced to a preset value, so that the growth of metal grains in the bottom metal layer is further inhibited, the controllability and the stability of the deposition process of the bottom metal layer can be improved by reducing the deposition speed of the film forming process; by reducing the deposition vacuum degree of the film forming process, the shape of metal grains in the bottom metal layer can be more uniform, the bottom metal layer obtained through deposition is smoother, and meanwhile controllability is improved.

The application provides a visible light and infrared image registration method based on region similarity, and the method comprises the following steps: rendering a synthetic dataset with a graph with obvious corner features, training a key point detector on the synthetic dataset; performing scaling and grayscale processing on a registration image pair of visible light and infrared, inputting the key point detector to generate corresponding key point coordinates, and performing random homography transformation on the infrared and visible light images with key points to simulate the transformation relationship between the image pair, generating a grid through Delaunay triangulation, and processing the topological relationship of the point set and the triangular mesh generation; inputting the transformed image pair into a descriptor generation network, designing a region-based loss function, and training the registration relationship between the grids. The method effectively solves the problem of inconsistent corner points in cross-modal image matching, realizes high-precision and high-anti-interference-capability image registration, and can be applied to the fields of remote sensing image processing and target tracking.

The application discloses a kind of thin layer nanocomposite membranes and its preparation method and application, belong to membrane separation technical field.The method first polyamino monomer and 2,4,6-triformylphloroglucinol in organic solvent are catalyzed polymerization, and covalent organic polymer nanoparticles are prepared;Subsequently, the nanoparticles are reacted with sodium alginate to obtain hydrophilic modified nanoparticles;Finally, the modified particles are added to the aqueous phase, and the organic phase is interfacially polymerized and heat treated on the substrate to obtain a thin layer nanocomposite membrane.The application constructs a hydrophilic network and a charged nanopore, significantly improves the permeation flux of the membrane, while maintaining a high rejection rate for divalent salt, achieving the synergistic optimization of high flux and high ion selectivity, and can be applied to water treatment, desalination, magnesium-lithium separation and other fields.

The invention discloses a lithium iron phosphate positive electrode material, a preparation method thereof and a battery, and belongs to the technical field of batteries, the preparation method comprises the following steps: mixing an iron source, a lithium source, a phosphorus source, a dopant and a grinding agent, and carrying out dry ball milling to obtain precursor powder; and sintering the precursor powder under the protection of inert gas to obtain the lithium iron phosphate positive electrode material. According to the method, high-purity graphite / acetylene black is used as a grinding agent and a carbon source, a doping agent is added at the same time, a solvent does not need to be used, a ball-milled material does not need to be dried, uniform compounding of a precursor and construction of a conductive network are achieved in one step through the mechanochemical effect, and then the conductive network is obtained through high-temperature sintering. The prepared lithium iron phosphate positive electrode material has excellent electrochemical performance and relatively high compaction density, and still keeps relatively good electrochemical performance in a low-temperature environment, so that a new development direction is provided for production of lithium iron phosphate.

The invention relates to a mobile zoom optical system which comprises a first optical element group, a second optical element group and a third optical element group which are sequentially arranged from an object side to an image side in the optical axis direction, the first optical element group is fixed, and the second optical element group and the third optical element group are movable. The first optical element group comprises a first lens barrel and a first lens, and the second optical element group comprises a second lens barrel, and a second lens, a second spacing element, a third lens and a fourth lens which are assembled in the second lens barrel. And the third optical element group comprises a third lens cone, and a fifth lens, a sixth lens and a seventh lens which are assembled in the third lens cone and have negative focal power. The mobile zoom optical system satisfies the following conditions: 1.60 lt; f < 234 > / dbslt; 2.05, 2.06, 2.07; 3.35 lt, 3.35 lt; r3 / EPb2lt; 5.50); 1.75 lt, 1.75 lt; r4 / EPb2lt; and 4.55.