64results about How to "Precise control of particle size" patented technology

The invention relates to an accurate aerial spraying control system and method for an aircraft.The accurate aerial spraying control system for the aircraft comprises a controller, a droplet particle size control unit, an airborne weather measurement unit and an airborne altitude measurement unit.The controller is connected with the droplet particle size control unit, the airborne weather measurement unit and the airborne altitude measurement unit.The airborne weather measurement unit is used for acquiring information of the environment where the aircraft is located.The airborne altitude measurement unit is used for acquiring information of the altitude of the aircraft relative to ground.The controller is used for calculating a target value of the particle size of sprayed droplets according to the information of the environment and the information of the altitude and sending a control instruction to the droplet particle size control unit according to the target value.The droplet particle size control unit is used for adjusting the particle size of droplets according to the control instruction.By means of the accurate aerial spraying control system and method for the aircraft, accurate control over a droplet depositing area is achieved, and the particle size of droplets can be accurately regulated and controlled according to environmental requirements, so that the ground depositing effect of droplets is optimized, influences of attitude changes of the aircraft on spraying are overcome, and the aerial spraying effect is improved.

The disclosed preparation method for nano-polymer microemulsion in ink-jet printing comprises: using soft monomer butyl acrylate as main polymonomer for well film-forming flexible; adding comonomer with cross-linkging group to form three-dimensional space network structure and fix the color particle hard on textile fabric to prevent film tacky and endow the fabric with well resistance ability; adding polymerisable surfactant to let the polymer microemulsion have super stability even with much soft monomer and average size less than 100nm hard to agglomeration. This invention can obtain the product with small size and narrow distribution.

The invention provides a method of preparing molybdenum disulfide microspheres through sulfurizing and reducing a soluble molybdenum source in a reversed-phase microemulsion system. The method includes a) a step of preparing a reversed-phase microemulsion A through adopting polyethylene glycol octylphenol ether (Triton X-100), n-hexanol, cyclohexane and an aqueous solution of the soluble molybdenum source as a surfactant, a cosurfactant, an oil phase and a water base respectively, b) a step of adding an aqueous solution containing a sulfur source and a reductant into the reversed-phase microemulsion A to obtain a reversed-phase microemulsion B, and c) a step of transferring the reversed-phase microemulsion B to a hydrothermal reactor, performing crystallization thermal treatment at a certain temperature for a certain period of time, separating, washing, and drying the reaction product to obtain the molybdenum disulfide microspheres. The method is simple and mild in reaction conditions. Through characterization by a scanning electron microscope and a transmission electron microscope, the molybdenum disulfide microspheres have the characteristics of being solid or hollow, smooth or wrinkled in surface, and the like.

The invention discloses a crystal seed growth method for preparing gold nano-particles, relates to a crystal seed growth method for preparing gold nano-particles and aims at solving the technical problems of the traditional crystal seed growth method for preparing large-particle size gold nano-particles that raw materials have toxicity, impurities are introduced into a reducing agent, and the prepared gold nano-particles are poor in monodispersity and inhomogenous in morphology. The crystal seed growth method comprises the following steps: 1, preparing a gold seed; and 2, preparing the gold nano-particles by virtue of the crystal seed growth method. The crystal seed growth method has the advantages that 1, the prepared gold nano-particles are uniform in particle size and morphology and is spherical, the particle size of the gold nano-particles can be accurately controlled by changing a ratio of HAuCl4 and the gold seed, the standard dispersity error of the prepared gold nano-particles is smaller than 10 percent, and the particle aspect ratio is smaller than 1.1; and 2, as rapid reaction is carried out at room temperature, and H2O2 is utilized as a reducing agent, after reaction, the H2O2 can be removed by simple decomposition reaction or boiling, and a new chemical component and impurities are not introduced on the basis of original gold seed.

The invention relates to a preparation method for spherical lithium ferric phosphate used as a lithium ion battery anode material. The preparation method comprises the following steps: respectively dissolving a ferric iron compound and a phosphorus source compound in deionized water to prepare a water phase solution A and a water phase solution B, and adding the solution A and the solution B slowly into organic oil to form a water-in-oil system C; washing and drying the water-in-oil system C after precipitation and centrifugal separation to obtain a spherical ferric phosphate predecessor; mixing the ferric phosphate predecessor, a lithium source compound and a carbon source compound, and calcining the mixture for 1 to 24 hours at 550 to 850 DEG C under the protection of inert gas so as to obtain the spherical lithium ferric phosphate anode material with high bulk density and the tap density of 1.5 to 2.2 g / cm3. The preparation process has simple operation and easy control, and facilitates realization of the large-scale industrialized production. In addition, the prepared spherical lithium ferric phosphate anode material has the high tap density reaching 1.5 to 2.2 g / cm3.

The invention discloses a method for preparing an organic hydrogenation catalyst based on noble metal nanoparticles. The method is as below: first conducting amino modification on a substrate material, and then preparing a noble metal nanoparticles layer on the amino modified substrate material, so as to obtain the organic hydrogenation catalyst based on noble metal nanoparticles. The method can load ultra small noble metal nanoparticles with a variety of particle sizes on a variety of substrate surface, and the particle size can be precisely controlled; and the catalyst shows excellent catalytic activity in organic hydrogenation. The method can prepare novel noble metal nano catalyst based on ultra small size, so as to achieve hydrogenation activity much higher than that of conventional catalyst materials.

The invention discloses a mass production method of a single crystal cobalt-free lithium-rich manganese-based binary material precursor. The method comprises: 1, preparing a solution A from a nickel salt and a manganese salt, and adopting a NaOH solution as a precipitating agent B, ammonia water as a complexing agent C and a sodium sulfite solution as a reducing agent D; 2, preparing a base solution, introducing N2, enabling the pH value of the base solution to 11-13 by using ammonia with the concentration of 3-10 g / L, and stirring at a temperature of 30-60 DEG C under a stirring speed of 200-500 rpm; step 3, adding the solution A, a solution B, a solution C and a solution D into a reaction kettle at the same time, and keeping the pH at 10-12, the concentration of supernatant liquid ammonia at 3-10 g / L, the temperature at 30-60 DEG C and the stirring speed at 200-500 rpm; and 4, stopping feeding after D50 reaches the target particle size, and carrying out centrifugal washing, drying, screening, iron removal and packaging to obtain the single-crystal cobalt-free lithium-rich manganese-based binary material precursor.

The invention belongs to the field of inorganic functional materials, and particularly relates to a preparation method of a manganese dioxide / graphite oxide-based self-driven micromotor. The preparation method comprises the following steps: firstly, preparing a dispersion having a certain concentration and containing sodium lauryl sulfate, nanometer manganese dioxide, graphene oxide and chitosan as an internal phase fluid, using an organic solvent containing a surfactant as an external phase fluid, controlling a certain flow rate to enable the internal phase fluid and the external phase fluidto run through a constructed microfluidic device, forming a monodisperse water / oil emulsion in a collecting pipe, and then collecting and freezing into ice balls by collecting liquid placed in liquidnitrogen, filtering the produced ice balls, and performing freeze drying to obtain the self-driven micromotor. The micromotor can effectively remove pollutants from water through adsorption, and has agood application prospect in the field of environmental protection.

The invention discloses a preparation method of a concave cuboid Pt-Ir alloy nanocrystal catalyst having a high-index crystal surface structure, and belongs to the technical field of preparation of afuel cell catalyst. The Pt-Ir alloy catalyst exists in a green and novel non-aqueous medium, namely a deep-eutectic solvent, and a concave cuboid Pt-Ir alloy nanocrystal with a {hk0} high-index crystal surface-structure surface is prepared by employing an electrochemical cyclic voltammetry method under a condition without any surfactant. The surface of the concave cuboid Pt-Ir alloy nanocrystal catalyst is a high-index crystal surface, the concave cuboid Pt-Ir alloy nanocrystal catalyst is provided with an opening surface structure, a large amount of active sites are provided, the poison capability of an intermediate body resistant to CO and the like is remarkably improved by a dual-functional mechanism of an alloy surface structure, and the concave cuboid Pt-Ir alloy nanocrystal catalysthas excellent electrocatalytic performance on fuel micromolecules such as formic acid, methyl alcohol and ethyl alcohol.

The invention relates to a preparation method of a highly dispersed silicon dioxide microsphere with a controllable particle size. The preparation method comprises the following steps: (1) evenly mixing ethyl ortho-silicate and anhydrous ethanol; (2) dissolving inorganic salts into a mixed solution of ammonia water, anhydrous ethanol, and deionized water, wherein silicon dioxide microspheres with different particle sizes can be obtained according to the species and addition amounts of inorganic salts; and (3) stirring the solution obtained in the step (2) at a high speed, adding the solution obtained in the step (1) into the solution obtained in the step (2), reducing the stirring speed after the solutions are evenly mixed; two hours after reactions, carrying out centrifugal separation, and drying to obtain the silicon dioxide microsphere. The adopted equipment is simple, the operation is convenient, the repeatability is high, and the requirements on external environment are low. The particle size of the microsphere can be precisely controlled, during the preparation process of highly dispersed silicon dioxide microsphere. The reaction time is not changed. The prepared silicon dioxide microsphere has good dispersibility without grafting modification.

A preparation method of a TiO2 / MnS composite photocatalytic coating agent comprises the steps that titanium containing salt, manganese containing salt and thioacetamide are selected as raw materials; concentrated nitric acid is adopted as a hydrolysis buffering agent and drop-added to a titanium salt precursor, namely, the titanium containing salt, until the pH value of the mixture solution is equal to or lower than 2; then water is drop-added so as to hydrolyze titanium salt; TiO2 floccule is obtained after water is drop-added and the mixture is stirred for 0.5-1.5 h; the manganese containing salt is mixed with water, the thioacetamide is taken as a sulfur source, the reaction temperature is controlled in the range from 50 DEG C to 70 DEG C, and MnS floccule is obtained after the mixture is stirred and reacted for 0.5-1.5 h; the TiO2 / MnS composite photocatalytic coating agent is obtained after the TiO2 floccule and the MnS floccule are centrifugalized, cleaned for three time, mixed and stirred for 2-28 hours. The preparation method of the TiO2 / MnS composite photocatalytic coating agent has the advantages that MnS and TiO2 are fully composited, and high dispersion and uniform distribution state are realized.

The invention provides an oil-containing sewage cyclone flotation evaluation device and a method using same. The oil-containing sewage cyclone flotation evaluation device comprises air floatation equipment, gas dissolving equipment, etc. The air floatation equipment comprises a cyclone cylinder, a speed adjusting motor, an inner cylinder, etc. The inner cylinder rotates for making sewage perform cyclone motion and forming a cyclone field which is uniform in the axial direction. The rotation speed of the inner cylinder is adjusted through the speed adjusting motor for realizing cyclone strength change, thereby evaluating effect of the cyclone strength to cyclone flotation de-oiling performance. The gas dissolving equipment comprises a multiphase gas dissolving pump, an expanding tube, etc. Through adjusting the flow and the pressure of the gas dissolving pump, parameters such as bubble diameter and dissolved gas amount are controlled for evaluating effect of a bubble characteristic to the cyclone flotation de-oiling performance. Through detecting oil content change of the sewage at the sampling opening of the air floatation equipment before and after testing, the effect of cyclone strength and bubble characteristic to the cyclone flotation de-oiling performance is evaluated. The oil-containing sewage cyclone flotation evaluation device and the method using same can realize optimization for key parameters of a cyclone flotation process, thereby laying the foundation for optimized design and high-efficiency operation of cyclone evaluation equipment.

The invention relates to an iron-containing catalyst, in particular to a method for preparing carbon coated iron-cementite magnetic nanopaticles. According to the method, by means of a mixed solutionof ferric citrate and potassium bromide, ferric citrate particles which are evenly distributed on the surface of a potassium bromide carrier and serves as an iron metal source are obtained through thefreeze drying technology, and a ferric oxide-potassium bromide catalyst precursor is obtained through calcining; and then the carbon coated iron-cementite magnetic nanopaticle products with a carbonlayer as an outer layer and iron and cementite forming a core are prepared through a chemical vapor deposition method. The defects that in the prior art, the prepared carbon coated iron nanoparticlesare low in purity, poor in particle dispersity and particle size controllability, low in particle crystallization degree, poor in stability and not good in overall performance are overcome.

The invention provides an expansion screen pipe which comprises an inner layer pipe, a middle layer pipe and an outer layer pipe, wherein the inner layer pipe, the middle layer pipe and the outer layer pipe are fixed and mounted in a sleeved mode in sequence from inside to outside. Multiple kerfs are distributed in the pipe wall of the inner layer pipe, the middle layer pipe is formed by coiling filaments spirally, and multiple holes are also distributed in the pipe wall of the outer layer pipe. The expansion screen pipe has the advantages that the granulometric class of filtered gravel can be controlled accurately, an oil drainage area is enlarged through expansion hole enlargement, oil flow resistance is reduced at the same time, and crude oil produced by a single well daily can be improved by 30-50 percent.

The invention discloses a preparation method for a nanometer composite metal oxide. The preparation method comprises the following steps: with a nanometer metal oxide, which is one of the main metal components of the composite metal oxide, as a nanometer template, evenly dispersing the nanometer template in aqueous solutions of water-soluble salts of other metal components in the composite metal oxide so as to obtain mixed dispersion liquid, wherein the main metal component refers to a metal component with a molar content accounting for more than 30% of the molar content of all metal components; drying the mixed dispersion liquid through spray drying or vacuum freeze drying so as to obtain a powder mixture; and subjecting the powder mixture to heat treatment to allow oxides formed by the decomposition of the water-soluble salts to be compounded with the nanometer metal oxide so as to form the nanometer composite metal oxide. The preparation method of the invention significantly reducescost and operation difficulties, avoids the large-scale use of organic compounds, and prevents the problems of impure composition and difficultly-controllable microstructure caused by nonuniform mixing and the introduction of ball milling impurities.

The invention discloses a spiral-flow sectional tube type liquid stirring device. A rectifying tube is arranged in an accommodating groove; and a plurality of turbulent flow layers and a rectifying and mixing layer are arranged on the sides of the rectifying tube. After flowing through the turbulent flow layers and the rectifying and mixing layer, fluid can be stirred to form a particulate structure. When the stirring device is used for materials with relatively high viscosity, such as heavy oil, rubber and the like, particles can be relatively uniformly distributed under the condition of not adding an expensive interface active agent (an emulsifier), so that the material cost is saved and the problems of environmental pollution and acid corroded pipelines probably cause by the interface active agent are solved. Particularly, the proportion of the aperture size to the total area on the turbulent flow layers and the rectifying and mixing layer can be calculated to precisely control refining grain diameter. The device has the advantage of improving quality and contributing to automatic mass production.

The invention discloses a method for preparing graphene material at high temperature and high pressure and belongs to the technical field of carbon material, and the method is used for solving the problems of the prior art and achieving preparation of graphene. The method comprises the following steps; pre-pressing a solid organism with carbon so as to obtain a block raw material; putting the block raw material into a mold chamber, and performing heat preservation and pressure maintaining for more than 10 minutes, wherein the heating rate is 5 DEG C per minute; further releasing the pressure, cooling, demolding and treating to obtain the graphene material. The value of the pressure P in the step of performing heat preservation and pressure maintaining ranges from 400MPa to 20000MPa, and the temperature T ranges from 900 DEG C to 1600 DEG C. By virtue of high temperature and high pressure, the particle size, thickness and surface opening slit size of spherical, bar-shaped and flake graphene are precisely controlled; the defects of the spherical, bar-shaped and flake graphene are precisely controlled; the method is environmental-friendly as no acid, alkali or toxic and harmful reagents are used; multiple graphene materials prepared by using the method are good in repeatability and applicable to industrial production.

The invention discloses vanillin microcapsule droplets and a preparing method thereof. The vanillin microcapsule droplets are prepared through the following steps that 1, vanillin is taken and dissolved in solvent to prepare a core material solution serving as fluid L1; 2, chitosan is taken and dissolved in a glacial acetic acid water solution, and the pH value is adjusted to 6.5-6.8 to prepare a wall material solution serving as fluid L2; 3, L1 and L2 pass through a microfluidic device to prepare the vanillin microcapsule droplets. By adopting the microfluidic technology, the laminar flow characteristics of the fluid in microchannels are used, the particle size of the vanillin microcapsule droplets can be controlled by fixing core material L1 flow speed and adjusting wall material L2 flow speed, the vanillin microcapsule droplets are arrayed in the channels in order, and the vanillin microcapsule droplets with the particle size uniform and controllable are obtained.

The invention provides a method for regulating and controlling the particle size of silicon dioxide microspheres. The method comprises the following steps that an ammonium chloride aqueous solution and a tetraethoxysilane ethanol solution with different concentrations are mixed, the pH value of the solution is regulated and controlled through triethylene tetramine, at the normal-temperature and normal-pressure conditions, a submicron-order and micron-sized silicon dioxide sphere precursor with adjustable particle size is successfully synthesized, an obtained drying sample is placed in a mufflefurnace, calcining is carried out for 2-6 hours at the temperature of 500-800 DEG C, and cooling is carried out to reach the room temperature so as to obtain silicon dioxide with different sphericaldiameters. The regulation and control method has the advantages that a required device is simple, the operation is simple and easy, the efficiency is high, and accurate control over the size of the product can be realized; and the particle size of the silicon dioxide microspheres prepared through the method ranges from 200 nm to 2 microns, the synthetic path is simple, the cost is low, the application is wide, and the like.

A method for preparing concave cubic platinum-rare earth alloy nanocrystals based on a eutectic solvent is disclosed, and belongs to the technical field of fuel cell catalyst preparation. The eutecticsolvent which is novel, green and non-aqueous is adopted as a medium to prepare the concave cubic platinum-rare earth alloy nanocrystals with a surface of a {hk0} high-index crystal face structure byelectrochemical cyclic voltammetry without the need of any surfactant. The high-index crystal face has an open type surface structure so that a high number of active sites can be provided and catalyst performance can be significantly improved through a double-function mechanism of an alloyed surface electron structure, and therefore, the nanocrystals have excellent electrocatalytic performance for fuel molecules such as formic acid, methanol and ethanol, and have broad application prospects in the field of fuel cells, the field of electrosynthesis, and the like.

The invention relates to an oil soluble nanometer scintillation crystal and a preparation method thereof.LaCl3 and RECl3 lanthanide compounds are heated under the inert gas shielding and dissolved into an oleic acid and octadecene mixed solution, a NH4F methanol solution is added dropwisely at uniform speed on the stirring condition, a reaction is performed for 10-120 min at the temperature of 260-320 DEG C after methyl alcohol is removed, the oil soluble nanometer scintillation crystal with the average grain size being 4-10 nanometers is obtained, RE is the lanthanide Tb or lanthanides Tb and Ce, the oil soluble nanometer scintillation crystal of different fluorescence emission strengths is obtained by changing the varieties and / or ratio of the LaCl3 and the RECle lanthanide compounds, and the obtained oil soluble nanometer scintillation crystal has the advantages of being high in fluorescence intensity and good in fluorescence stability under X-ray irradiation excitation, and can be widely applied to the fields of biological medicine, material science and the like.

The invention relates to a copper-based catalyst for preparing ethanol by electrocatalytic reduction of carbon dioxide, and a preparation method and application thereof. The catalyst is a supported bimetallic copper-based catalyst; and the carrier is a carbon material or a metal material, and the active substance is a gold-copper heterojunction. According to the preparation method, the carbon material or the metal material is used as the carrier, sodium citrate and PDDA are used as stabilizers, the binary metal copper-based catalyst is prepared through an electrostatic self-assembly method, and the obtained catalyst has a gold-copper binary heterojunction. According to the invention, the binary catalyst with different contact structures can be prepared by regulating and controlling the surface coating of the metal particles only by regulating and changing the variety and the dosage of the stabilizer, and the catalyst shows very high selectivity on preparation of ethanol by electrocatalytic reduction of carbon dioxide.

The invention provides a method for preparing hollow carbon nanospheres through a non-template method and application of the hollow carbon nanospheres. The method includes the steps that with polymeric vesicles being precursors, calcination is performed under protection of inert gas, and the hollow carbon nanospheres are obtained; the polymeric vesicles are formed by polymers P (PMDA-alt-ODA) in a self-assembly mode. No templates are needed according to the preparing method, the preparing process is simple, the preparing period is short, and the method is environmentally friendly; the particle size of the prepared hollow carbon nanospheres is 110-820 nm; because the polymers P (PMDA-alt-ODA) contain a large number of benzene rings, the hollow carbon nanospheres are provided with graphite-like ordered structures, the carbonation rate reaches 50%, and the hollow carbon nanospheres have very good conductive capacity and electricity storage capacity and can be used as active electrode materials of conductive materials, electricity storage materials or supercapacitors.

The invention discloses a method for preparing a transition nanometer oxide with a uniform grain size by a coprecipitation method. The method comprises the steps of selecting a soluble metal salt as a raw material; dissolving in a water-organic mixed solvent phase; adding a composite ligand, and then adding a precipitator to carry out coprecipitation reaction; simultaneously controlling the pH value within a range of 7-9 at any time; filtering to obtain a sediment product. Various reaction conditions and ligand variety and quantity are synergistic, so as to achieve the technical effects of uniform growth, uniform particle size, controllable morphology and high crystallinity of particles by using the composite ligand and accurately controlling a plurality of reaction parameters. The obtained oxide nanoparticles have narrower particle size distribution and higher crystallinity, and are applicable to the fields such as biomedicine detection and the like.

The invention relates to blue fluorescent powder and a preparation method thereof, wherein the chemical general formula of the fluorescent powder is A1-xEuxBySi2O2N2+y, A is any one or two of Sr, Ca and Ba, B is any one or two of Al, Ga, In, Y and La, x is greater than or equal to 0.01 and less than 0.1, and y is greater than 0 and less than 0.1. The invention further discloses a preparation method of the fluorescent powder. According to the invention, a small amount of Al, Ga, In, Y and La elements are added into BaSi2O2N2 structure fluorescent powder, so that the wavelength of the fluorescent powder can be adjusted, the stability of a crystal structure and the nucleation consistency are improved, the brightness of the fluorescent powder is improved, and the damp-heat resistance of the fluorescent powder is improved; and according to the preparation method, a specific raw material treatment process and a sintering mode are applied, so that the uniformity and controllability of product particles are improved, meanwhile, the requirements on using equipment are reduced, and the production efficiency is improved.

The invention discloses a preparation method and a preparation mechanism of embryo microspheres and a preparation method and a preparation device of microspheres. The preparation method comprises thefollowing steps of: conveying a microsphere generation liquid to a porous film positioned in a receiving liquid through a liquid conveying member to form the embryo microspheres; flowing the embryonicmicrospheres falling off the porous film along a channel filled with the receiving liquid to harden the embryo microspheres to form the microspheres; and collecting the microspheres. The flow rate ofthe liquid output by the liquid conveying member is controllable, and the amount of the microsphere generation liquid output per unit time can be directly controlled, so that the particle size and uniformity of the generated microspheres can be better regulated and controlled. In addition, since bubbles are prevented from being mixed into the embryo microspheres, the problem that the microspherescannot be finally formed for the reason that the surface tension distribution of the embryo microspheres changes can be avoided, and the product yield of the microspheres is improved.

The invention discloses a method for preparing coated Al2O3 / Al composite powder through a hydrothermal method. The method specifically includes the steps that aluminum powder is added into a beaker firstly, distilled water is added into the beaker, and the mass ratio of the aluminum powder to the distilled water is 1:1-1:5; stirring is conducted, and slurry is formed; an aluminum nitrate solution with the concentration being0.01 mol / L to 1 mol / L and an ammonia water solution are dripped into the aluminum powder slurry at the same time, the pH of the slurry is kept between 7 to 11, stirring is conducted for 0.5 h to 3 h continuously, the slurry in the beaker is poured into a reaction kettle, the reaction kettle is put into an oven, the temperature of the oven is increased to 100 DEG C to 300 DEG C, and heat insulation is conducted for 1-200 hours; the obtained slurry is cleaned three times with distilled water and then cleaned one time with absolute ethyl alcohol; and the coated Al2O3 / Al composite powder can be prepared after drying. The method has the beneficial effects of being easy and convenient to operate, easy to control, low in energy consumption and the like.

The invention discloses a method for preparing an organic hydrogenation catalyst based on noble metal nanoparticles. The method is as below: first conducting amino modification on a substrate material, and then preparing a noble metal nanoparticles layer on the amino modified substrate material, so as to obtain the organic hydrogenation catalyst based on noble metal nanoparticles. The method can load ultra small noble metal nanoparticles with a variety of particle sizes on a variety of substrate surface, and the particle size can be precisely controlled; and the catalyst shows excellent catalytic activity in organic hydrogenation. The method can prepare novel noble metal nano catalyst based on ultra small size, so as to achieve hydrogenation activity much higher than that of conventional catalyst materials.

The invention discloses a method for preparing graphene material at high temperature and high pressure and belongs to the technical field of carbon material, and the method is used for solving the problems of the prior art and achieving preparation of graphene. The method comprises the following steps; pre-pressing a solid organism with carbon so as to obtain a block raw material; putting the block raw material into a mold chamber, and performing heat preservation and pressure maintaining for more than 10 minutes, wherein the heating rate is 5 DEG C per minute; further releasing the pressure, cooling, demolding and treating to obtain the graphene material. The value of the pressure P in the step of performing heat preservation and pressure maintaining ranges from 400MPa to 20000MPa, and the temperature T ranges from 900 DEG C to 1600 DEG C. By virtue of high temperature and high pressure, the particle size, thickness and surface opening slit size of spherical, bar-shaped and flake graphene are precisely controlled; the defects of the spherical, bar-shaped and flake graphene are precisely controlled; the method is environmental-friendly as no acid, alkali or toxic and harmful reagents are used; multiple graphene materials prepared by using the method are good in repeatability and applicable to industrial production.