38results about How to "High sphericity" patented technology

A method for preparing spherical aluminum hydroxide micropowder includes the following steps: A sodium aluminate solution A is prepared by mixing aluminum hydroxide and sodium hydroxide; after heating, a self-made polyvinylpyrrolidone-g-polysiloxane additive is added, and the mixture is continuously heated and stirred to form solution B; sodium bicarbonate is then added and the reaction is continued with stirring; after the reaction is complete, the mixture is filtered while hot to obtain the filtrate, which is solution C; solution C is heated under stirring conditions, and after the reaction is complete, the temperature is lowered at a certain rate to obtain a mixed product; the mixed product is filtered, washed, and dried to obtain spherical aluminum hydroxide. The spherical aluminum hydroxide prepared by this method has a regular morphology and concentrated particle size distribution, with a D50 of approximately 7-10 micrometers. Compared with irregularly shaped aluminum hydroxide of the same particle size, it has better filling performance, effectively improving the problems of poor dispersibility and high viscosity caused by high filling of aluminum hydroxide in polymer materials, and improving the subsequent processing performance of the material.

This invention belongs to the field of electronic packaging and soldering materials technology, and relates to a lead-free solder powder for reflow soldering and its preparation method. This lead-free solder powder is based on a Sn-Ag-Cu alloy system, and achieves melt purification, β-Sn grain refinement, and interface IMC stabilization by adding trace amounts of Ce and Ni elements. Its composition, by mass percentage, is: Ag 2.9%–3.1%, Cu 0.45%–0.55%, Ce 0.01%–0.10%, Ni 0.01%–0.05%, with the balance being Sn and impurities. During preparation, a Ce-Ni master alloy is used to introduce microalloying elements, followed by vacuum melting, inert gas atomization, and surface treatment to obtain spherical solder powder. The resulting solder powder has low oxygen content, good wettability, slow interface IMC growth after reflow, high solder joint strength, and excellent thermal cycling reliability, making it suitable for high-reliability electronic packaging applications.

The application belongs to the technical field of polymer materials, and particularly relates to a nylon powder and a preparation method and application thereof. The nylon powder comprises high-viscosity nylon resin, low-viscosity nylon resin and an additive, wherein the relative viscosity of the high-viscosity nylon resin is 1.75-1.85, the relative viscosity of the low-viscosity nylon resin is 1.55-1.65, the mass ratio of the high-viscosity nylon resin to the low-viscosity nylon resin is 10:1-3, and the additive comprises an antioxidant. The high-viscosity nylon resin and the low-viscosity nylon resin with specific viscosities are compounded and used in proportion, the high-viscosity nylon resin serves as a skeleton of a hydrogen storage bottle inner container and provides mechanical property support, and the low-viscosity nylon resin provides fluidity and ensures few defects in bottle forming. The use of the nylon powder of the application improves the mechanical property of the hydrogen storage bottle inner container and the integrity of the inner container structure, and a stable and defect-free type IV nylon hydrogen storage bottle inner container is prepared.

The invention provides spherical copper oxide water atomization production equipment and a preparation process thereof, and relates to the technical field of copper oxide preparation, firstly, a medium-frequency induction smelting furnace is used for smelting and pre-oxidizing a copper material, and then an atomization tower and a porous rotary damping spray head in the atomization tower are used for carrying out water atomization crushing and oxidation on molten copper; and then a rotational flow dehydrator and an airflow drying tower are used for dehydration and deep oxidation. Copper liquid pollution is prevented through nitrogen whole-process protection and smelting segmented oxidation, the rotating speed of the porous rotary damping spray head is stabilized through wavy concave-convex structure embedment and constant damping design of ball groove bearing balls, and particle aggregation and nozzle deposition are avoided in combination with pulse type intermittent jet flow. The copper oxide powder with high sphericity, uniform granularity and pure surface is obtained, the production efficiency of spherical copper oxide is improved, the service life of a nozzle is prolonged, and energy consumption is reduced.

The invention relates to the technical field of high-activity metal powder, in particular to high-environmental-stability aluminum-lithium alloy powder and a manufacturing method and application thereof.The high-environmental-stability aluminum-lithium alloy powder comprises, by weight, 1.0-10.0 wt.% of Li, 1.0-10.0 wt.% of Al, 1.0-10.0 wt.% of Ti, 1.0-10.0 wt.% of Ti, 1.0-10.0 wt.% of Ti, 1.0- 0.1 to 5.0 wt.% of Zr; 0.01 to 2.0 wt.% of Ti; 0.05 to 3.0 wt.% of RE; wherein RE is a rare earth element and at least comprises Y, Ce, La or a combination thereof, the sum of Zr, Ti and RE does not exceed 8.0 wt.%, and the balance is Al and inevitable impurities. The method has the effect of improving the use stability and the machining consistency of the aluminum-lithium alloy powder.

The application provides a silicon-carbon composite negative electrode material and a preparation method and application thereof, and belongs to the technical field of new energy materials and electrochemistry. Silicon powder and metal oxide are tightly combined through sand milling to build a continuous and stable structure, the volume expansion of the silicon powder and the metal oxide is inhibited, the stress of the silicon powder is released, then the sand-milled composite slurry is mixed with carbon material, and spray drying granulation and carbonization treatment are performed to prepare the negative electrode material. Based on the mutual stability effect, the application can accommodate and relieve the large volume expansion of the silicon material, and the stability of the material is maintained. The prepared composite negative electrode shows extremely low volume expansion (<20%). The metal oxide in the application has the ability to stabilize the SEI film and improve the conductivity. In combination with the addition of the carbon material, the conductivity of the composite material is synergistically improved, and the electrochemical performance is improved. Therefore, the prepared composite material has high sphericity, high tap density and excellent electrochemical performance.

The invention belongs to the technical field of inorganic materials, and particularly relates to a preparation method of high-purity barium carbonate. High-purity barium carbonate is prepared from a barium chloride solution and an ammonium bicarbonate solution through a coprecipitation method, a crystal form control agent is added into the barium chloride solution in advance, and a surfactant is added into the ammonium bicarbonate solution, so that an auxiliary agent is adsorbed to a potential crystal nucleus site in advance, the liquid phase interfacial tension is reduced, and the uniformity of a barium carbonate precipitation reaction is ensured; hyperbranched polycarboxylic acid and tartaric acid are compounded to form a crystal form control agent, polyacrylic acid and citric acid are compounded to form a composite dispersing system, the crystal form control agent, a surfactant and a composite dispersing agent are added, and the pH value in the reaction process is controlled, so that the prepared barium carbonate has higher purity and sphericity and narrower particle size distribution.

This invention provides a spherical TC4 alloy fine powder, its preparation method, and its application, belonging to the field of alloy material preparation technology. The preparation method of the spherical TC4 alloy fine powder includes the following steps: S1: Hydrogenation pre-crack formation, using spherical TC4 coarse powder particles as raw material, heating to 700~1000℃ in a hydrogen atmosphere, and holding at that temperature for 20~90 min; S2: Preparing spherical TC4 titanium alloy powder using radio frequency plasma hydrogen explosion; the hydrogen explosion gas includes hydrogen and inert gas; S3: After ultrasonic separation of the spherical TC4 titanium alloy powder from step S2, the spherical TC4 alloy fine powder is obtained. This achieves an integrated technical route of TC4 powder refinement and hydrogen explosion spheroidization, obtaining MIM powder with high sphericity and high flowability.

The application belongs to the technical field of lithium ion battery ternary precursors, and particularly relates to a high specific surface area high-nickel ternary precursor oxide as well as a preparation method and application thereof. The high specific surface area high-nickel ternary precursor oxide prepared by the method has a larger specific surface area, which can reach 180.19 m 2 / g, a high tap density, and loose and porous particles, and has high overall consistency, and can effectively improve the electrochemical performance of the positive electrode material when the positive electrode material is prepared. By adjusting the temperature and time of the calcination process, the application effectively reduces the moisture and organic impurity content, improves the sphericity of the later forming, effectively adjusts the half-peak of the ternary precursor oxide, and controls the specific surface area. By oxidizing the loose and porous high-nickel ternary precursor hydroxide, the structure of the ternary precursor oxide prepared is more stable, and the advantage is greater in the preparation of the subsequent ternary positive electrode material.

This invention relates to a stabilizer for preparing polycaprolactone and its application. The stabilizer is an asymmetric block copolymer comprising polycaprolactone segments and carbonyl-dependent segments, with an anchor-to-solubility ratio of 0.5 to 5.0, wherein the anchor-to-solubility ratio is the ratio of the number-average molecular weight of the carbonyl-dependent segments to that of the polycaprolactone segments. When the stabilizer of this invention is used to prepare polycaprolactone, polycaprolactone microspheres with controllable particle size range, narrow particle size distribution, and high sphericity can be obtained.

The invention discloses a multi-channel micro-fluidic chip and a preparation method of monodisperse chitosan microspheres in the multi-channel micro-fluidic chip, and belongs to the technical field of chitosan microsphere preparation, the multi-channel micro-fluidic chip comprises an upper layer substrate, a middle layer substrate and a lower layer substrate, and further comprises a continuous phase channel assembly, a disperse phase channel assembly and a microsphere collection assembly, the upper-layer substrate, the middle-layer substrate and the lower-layer substrate are fixedly connected in sequence from top to bottom, the upper-layer substrate is connected with a continuous phase channel assembly, the middle-layer substrate is connected with a dispersed phase channel assembly, the lower-layer substrate is connected with a microsphere collecting assembly, and the continuous phase channel assembly, the dispersed phase channel assembly and the microsphere collecting assembly are connected with one another. Through the mode, the monodisperse chitosan microspheres with uniform size and controllable morphology can be prepared.

The application provides SiC-ZrC-HfC composite powder for thermal spraying and a preparation method thereof, and belongs to the technical field of ultra-high-temperature ceramic powder.The SiC-ZrC-HfC composite powder prepared by the application has the characteristics of high uniformity of three components, narrow grain size distribution and good interface bonding, and the powder has high sphericity and good fluidity, and is suitable for thermal spraying process.The composite powder exhibits excellent ablation resistance and oxidation resistance at high temperatures, can meet the stringent requirements of aerospace field thermal protection components such as hypersonic aircraft, space shuttles and reusable launch vehicles, and simultaneously uses biomass carbon to partially replace graphite, thereby reducing production cost and energy consumption, reducing environmental pollution and having significant industrial application value.

The invention provides a polymer microsphere as well as a preparation method and application thereof. The polymer microspheres contain a first polyester material and a second polyester material, the first polyester material is polyester modified by a hydrophilic substance, and the second polyester material is polyester not modified by the hydrophilic substance; the polymer microsphere has a through pore channel structure, the through pore channel structure forms pores in the surface of the polymer microsphere, and the interior of the polymer microsphere is of a porous honeycomb structure. When the polymer microsphere provided by the invention is used as an organism filling agent, the polymer microsphere has a good adhesion effect on cells, better cell adhesion can be realized, and collagen secretion is improved; meanwhile, the through pore channel structure enables body tissues to grow more uniformly in the microspheres and strengthens the combination of the tissues and the polymer microspheres, so that the polymer microspheres are not easy to displace after being injected and in the later degradation process, and the safety is improved.

The application discloses a silicon nitride-aluminum nitride-based composite ceramic powder and a preparation method thereof. The preparation method of the composite ceramic powder comprises the following steps: preparing aluminum borate precursors and / or borate composite precursors by using a solid-phase reaction method; placing the prepared aluminum borate precursors and / or borate composite precursors in a high-temperature furnace; and performing a high-temperature nitriding reaction under a nitrogen or ammonia atmosphere to prepare binary or multi-element aluminum nitride-aluminum oxide composite powder. Then, the binary or multi-element aluminum nitride-aluminum oxide composite powder is combined with high-thermal-conductivity and high-strength silicon nitride-based spherical powder by airflow compounding to prepare the silicon nitride-aluminum nitride-based composite ceramic powder. The borate precursor solid-phase synthesis, one-step in-situ nitriding and airflow compounding process can be used to prepare the silicon nitride-aluminum nitride-based composite ceramic powder which can be applied to 6-35KV medium and high-voltage electric heating tubes. The process is free of carbon source and organic additive addition in the whole process, and complex processes such as hydrothermal treatment and spray granulation are abandoned, and the comprehensive production cost is reduced by 60%.

The material for a ceramic ball according to an embodiment of the present invention has a spherical surface section and a band-shaped section that is formed in the shape of a band. The material for a ceramic ball is characterized by having a roundness C in the range of more than 0% but not more than 2.5%, where C represents a roundness as observed from the height direction of the band-shaped section. When the material for a ceramic ball is subjected to a grinding process, the durability of the sharpening stone can be improved. In addition, at least one of aluminum oxide, silicon nitride, boron nitride, and zirconium oxide is applicable as the ceramic.

The present application relates to the technical field of preparation of tritium breeder, in particular to a method for batch preparation of Li2TiO3 tritium breeding microspheres and rich phase structure by centrifugal granulation, comprising the following steps: S1, Li2TiO3 ceramic powder is pretreated by spray granulation, then sprayed with a solution of xanthan gum for granulation, and sieved to obtain a green body; S2, the green body is added into a centrifugal granulator, and a second binder solution is sprayed at the same time, so that Li2TiO3 microsphere seeds with a preset diameter are generated by centrifugal granulation; S3, then the second binder solution is sprayed while lithium-containing ceramic powder is added for granulation and bonding; S4, the process of S3 is repeated until ceramic microsphere green bodies with the required diameter are obtained; S5, then deionized water is sprayed in the granulator and continues to roll for 3-8 min; S6, the ceramic microspheres obtained in S5 are dried at constant temperature and humidity, degummed, and sintered. The method can realize batch preparation of high-lithium-content tritium breeding microspheres with single-phase structure or multi-phase structure.

The invention discloses a preparation method of antioxidant nano-copper particles based on an intermediate metastable state, which comprises the following two steps: firstly, reacting copper salt with a first reducing agent and a pH regulator for 10-40 minutes in a first organic solvent of 70-130 DEG C to obtain copper-based intermediate particles of 20-25 nm; and then dispersing the intermediate in deionized water, adding a second reducing agent, a pH regulator and a coating agent, reacting at 70-130 DEG C for 20-60 minutes, so that the coating agent and copper atoms are deposited and synchronously bonded in situ under an alkaline condition to form a continuous coating layer with the thickness of 4-10nm, and finally obtaining the antioxidant nano-copper particles with the particle size of 30-40nm and high sphericity through epitaxial growth control. According to the preparation method, nucleation and growth processes are accurately regulated and controlled under mild conditions, and the nano-copper particles which are uniform in particle size, high in sphericity degree and long-acting in oxidation resistance are directly prepared.

The application relates to a device for preparing metal powder based on inductive coupling thermal plasma torch, and belongs to the technical field of metal powder preparation. The device comprises a feeder, a powder feeding gun, a plasma generating device, a spheroidizing chamber and a quenching chamber. The feeder sends metal raw powder carried by inert gas into the plasma generating device through the powder feeding gun. After being heated to form metal liquid drops, the metal liquid drops enter the spheroidizing chamber to become spherical liquid drops, and then enter the quenching chamber to be cooled into spherical powder. The upper end of the quenching chamber is connected with the spheroidizing chamber, the side wall is provided with upper, middle and lower quenching channels from top to bottom, and the three quenching channels are all composed of a plurality of inclined channels which are circumferentially distributed around an axis. The first, second and third cooling gases are respectively introduced into the three quenching channels to form rotational gas flows which are perpendicular to the axis, and the inert gas content in the three cooling gases increases gradually. The application can realize better cooling effect and improve the quality of the formed powder.

This invention discloses a high-purity ultrafine spherical silica powder, its production method, and its application, belonging to the technical field of high-value mineral material preparation and high-value utilization of industrial solid waste. The preparation method includes: flotation and acid washing of silica mud to obtain purified silica powder; air jet milling and air jet classification of the purified silica powder to obtain ultrafine silica powder; and feeding the ultrafine silica powder into a plasma reactor in the presence of an oxygen-containing flow, causing simultaneous oxidation and spheroidization to obtain high-purity ultrafine spherical silica powder. The oxygen volume concentration in the oxygen-containing flow is 25-60%; the ratio of the input power of the plasma reactor to the powder feeding rate of the ultrafine silica powder is 15 kWh / kg-50 kWh / kg. Based on the material characteristics of silica mud, this method achieves high-value utilization of silica mud through the synergistic regulation of pretreatment purification, precise particle size control, and energy-coupled spheroidization throughout the entire process, while possessing advantages such as low energy consumption, uniform product particle size, high purity, and good sphericity.

The present application relates to sintered Nd-Fe-B magnet preparation technical field, more specifically, the present application relates to a kind of recycled sintered Nd-Fe-B magnet, it is characterized in that;The recycled sintered Nd-Fe-B magnet is prepared by composite magnetic powder by magnetic field forming, sintering and aging, the composite magnetic powder is obtained by mixing the recycled magnetic powder and conventional neodymium iron boron double alloy powder according to mass ratio 20%-40%:60%-80%;Wherein, the recycled magnetic powder is derived from waste sintered Nd-Fe-B magnetic block, is prepared by gas atomization powder processing process, particle size D50 is 3.0 μm-4.5 μm, oxygen content≤300ppm;The present application aims at realizing the resource recycling of waste magnetic block, while ensuring that magnet has low heavy rare earth dependence, high magnetic performance and high stability.The magnet is prepared by mixing the recycled magnetic powder and conventional neodymium iron boron double alloy powder according to specific proportion, recycled magnetic powder is obtained by waste magnetic block by gas atomization powder processing, and conventional neodymium iron boron double alloy powder is designed by multi-element component optimization.

The application discloses a kind of nano-composite ceramic particles modified aluminum alloy powder for 3D printing and preparation method thereof, belong to metal additive manufacturing material technical field.The powder is composed of 7XXX series aluminum alloy powder matrix and TiC and TiB2 nanoparticles attached to its surface.TiC nanoparticle addition amount is 0.3%~1% of total mass, TiB2 is 0.1%~1%, total addition amount is controlled at 0.4%~1%.Two kinds of nanoparticles are uniformly coated on the surface of aluminum alloy powder by low-energy ball milling process, and the "TiB2-Al3Ti-Al" efficient heterogeneous nucleation path is constructed.The application realizes grain ultra-fining and completely crack-free forming under very low ceramic content, while avoiding the plasticity decline and surface treatment performance degradation caused by excessive ceramic phase.The obtained powder has excellent comprehensive performance, and is suitable for the manufacturing of high-strength, high-surface quality components.

The application provides an amorphous nanocrystalline soft magnetic alloy powder and a preparation method and a magnetic powder core thereof, and relates to the technical field of soft magnetic materials. The preparation method of the amorphous nanocrystalline soft magnetic alloy powder adopts high-energy electric pulse technology to realize instantaneous rapid heating and explosion of the amorphous alloy material, and realizes accurate control of the powder particle size by accurately controlling energy input parameters and interval parameters, thereby preparing high-sphericity soft magnetic powder with a median particle size of 0.5-5 mu m, significantly improving the uniformity and dispersity of the powder, and solving the problem of low particle size control accuracy in the prior art. Moreover, the preparation method has a simple process flow and low energy consumption, avoids impurities and defects introduced in the traditional multi-step process, and improves the purity and performance of the material. The prepared amorphous nanocrystalline soft magnetic alloy powder has the characteristics of small particle size, high sphericity, high saturation magnetization, low coercivity and high yield, and is particularly suitable for the field of high-frequency magnetic elements and precision electronic devices.

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 application discloses a kind of core-shell structure fast charging long cycle artificial graphite, its preparation method, negative electrode material and purposes, including, petroleum coke or acicular coke aggregate D50 8~20 μm, non-biomass hard carbon raw material powder D50 1~10 μm and pitch are mixed according to the mass ratio hard carbon: pitch = 1:9~5:5, aggregate: composite coating agent = 95:5~85:15, pre-mixing S1 is carried out at 100~200 DEG C, 160~220 DEG C melt kneading granulation S2, carbonization S3 is carried out at 600~1000 DEG C, and graphitization S4 is carried out at 2800~3200 DEG C, and core-shell structure artificial graphite is prepared by one-step method.The shell layer is composed of uniformly dispersed graphitized hard carbon and soft carbon, and is densely coated outside the artificial graphite core.The first reversible specific capacity of the product is greater than or equal to 350 mAh / g, the first coulombic efficiency is greater than or equal to 93%, and the capacity retention rate at 5.0C / 0.2C is greater than or equal to 84%, with excellent fast charging performance and cycle stability, simple process and low cost.

The application discloses a laser selective melting forming method in the technical field of additive manufacturing, and uses D406A ultra-high strength steel with low Mn content as a raw material, adopts a plasma rotating electrode atomization method to prepare metal powder, and then forms through a laser selective melting technology, so that D406A ultra-high strength steel printed parts with strength and impact performance equivalent to forged parts can be obtained through performance heat treatment. The D406A ultra-high strength steel formed through the laser selective melting has the advantages that the printed parts and the substrate can be separated through wire cutting without annealing, performance heat treatment can be directly carried out, and hot isostatic pressing treatment is not needed to reduce defects such as pores, so that the post-processing process is simplified, the production cycle is shortened, and the production cost is reduced.

This application relates to the field of ceramic powder processing, specifically disclosing a method for preparing spherical aluminum nitride powder, comprising the following steps: S1, dissolving a water-soluble organic carbon source in water by stirring to obtain a mixed solution; then adding alumina, mixing and stirring evenly, with the mass ratio of the water-soluble organic carbon source to alumina being 1:1-2, to obtain a reaction precursor; S2, subjecting the reaction precursor to spray drying and dry pressing to obtain a block; S3, subjecting the block to degreasing, carbonization, and nitriding reduction treatments to obtain a semi-finished product; S4, subjecting the semi-finished product to decarbonization, cooling, and pulverization to obtain the finished aluminum nitride powder; which has the advantages of high sphericity, high purity, and good thermal conductivity.

The application relates to the technical field of sodium ion battery negative electrode materials, and discloses resin-based hard carbon microspheres for sodium ion batteries and a preparation method thereof, which comprises the following steps: mixing styrene, a crosslinking agent and a catalyst to prepare an oil phase, dispersing the oil phase in a polyvinyl alcohol aqueous solution, and preparing resin microspheres through micro-suspension polymerization; and then performing air atmosphere pre-oxidation and inert atmosphere carbonization treatment to obtain a target product. Through regulation and control of a micro-suspension polymerization formula and a step-by-step heat treatment process, a dense spherical structure with rich closed pores and a suitable interlayer spacing is constructed, and the technical problems of low tap density and easy melting collapse of pyrolysis of traditional resin-based hard carbon are effectively solved. The obtained hard carbon microspheres have uniform particle size distribution, extremely high tap density and excellent powder fluidity, simultaneously exhibit high reversible specific capacity, high initial efficiency and excellent rate cycle stability, and are suitable for large-scale commercial application.

The invention discloses silk fibroin microspheres as well as a preparation method and application thereof, and the preparation method comprises the following steps: (1) dissolving silk fibroin in a water-phase solvent to obtain a dispersed phase; dispersing an emulsifier and fibroin binding peptide in an oil phase solvent to obtain a continuous phase; and adding the dispersed phase into the continuous phase, and stirring to obtain an emulsion. (2) slowly dropwise adding a chain segment inducer into the obtained emulsion to ensure that the concentration of the chain segment inducer in the system is slowly and uniformly increased, and stirring to obtain a metastable-state emulsion; and (3) annealing the obtained metastable-state emulsion at-10 DEG C to-2 DEG C, and unfreezing to obtain the silk fibroin microspheres. According to the method, the microspheres are formed only on the basis of physical induction of silk fibroin crystallization, no chemical cross-linking agent is added, and the biological safety is good. By balling in a solid-phase emulsion mold, the silk fibroin microspheres with the particle size of 20-100 microns, complete structure, high sphericity and freely controllable surface appearance and performance can be obtained, and clinical application is facilitated.

The application provides a preparation method of a zinc-doped lithium nickel cobalt manganese oxide positive electrode material, and the preparation method comprises the following steps: S1, mixing a nickel source, a cobalt source, a manganese source and a zinc source to obtain a mixed salt solution; S2, in an inert atmosphere, mixing the mixed salt solution and a precipitant solution by simultaneously dropping, continuously dropping the precipitant solution to adjust the pH value of the mixed solution to 10-11, performing a co-precipitation reaction, and obtaining a precursor slurry; S3, adjusting the pH value of the precursor slurry in step S2 to 7-8, performing solid-liquid separation, and drying the precipitate to obtain a precursor; and S4, mixing the precursor in step S3 with a lithium source, and sintering to obtain the zinc-doped lithium nickel cobalt manganese oxide positive electrode material. The method provided by the application can reduce the surface residual alkali content of the positive electrode material, and excellent cycle stability is obtained.

The application provides a kind of nanometer spherical cerium dioxide and its preparation method and application.The preparation method comprises the following steps: adding dispersant in cerium ion precursor slurry with pH of 0.1-4.0 to obtain a mixed solution, and then performing hydrothermal reaction on the mixed solution, and finally obtaining the spherical cerium dioxide by calcination.The spherical nanometer cerium dioxide prepared by the application has high sphericity, good dispersibility between particles, uniform and concentrated particle size distribution, and the size can be controlled between 30-500nm.