99results about How to "Uniform scale" patented technology

The invention discovers and proposes a characteristic that interior species of phenolic resin are nonuniform in distribution in a polymerization process, and discloses a method for preparing a hollow carbon sphere by utilizing the characteristic of phenolic resin. The method comprises: (1) putting phenol into water or a solvent, adjusting the pH, then adding aldehyde and stirring at a certain temperature for a period of time; (2) adding a corrosive agent in a reaction system, stirring at a certain temperature, and selectively removing a part with a relatively low polymerization degree inside a polymer by utilizing a solubility difference of interior species for different solvents, to obtain an intermediate product, that is, a hollow sphere of phenolic resin polymer; and (3) calcining the intermediate product that is obtained in step (2) in an inertia or reducing atmosphere, naturally cooling to room temperature, and thus completing preparation of the hollow carbon sphere. The method is simple and practicable, and the prepared hollow carbon sphere is uniform in shape and controllable in dimension. Moreover, by utilizing a characteristic that the phenolic resin can be in-situ polymerized on surfaces of different nanometer particles, on one hand, a multi-layer hollow structure can be prepared in a multi-cladding and layer-by-layer corrosion manner, and on the other hand, the different nanometer particles can also be packaged in a cavity in an in-situ mode, so as to prepare a nuclear shell or egg yolk-nuclear structure. The prepared hollow carbon sphere has a potential application value in aspects of silicon-carbon negative electrode material, Li-S battery, supercapacitor, heavy metal ion adsorption, and the like.

An apparatus and method for simulating the behavior of the drive system and the mechanism of machine tool or production-line machine by use of mathematical models of the drives and the mechanisms of the driven mechanical elements of the machine are disclosed. Preferably actual values for regulated and unregulated axes are calculated at the same time using NC- and PLC-models, respectively by an auxiliary computer using desired values provided by a digital controller. The actual values are then supplied to a mechanism model, preferably a geometric kinematic model, which produces a state signal that is fed back to the digital controller, preferably in real time. The result is an efficient, easy and cost-effective simulation that closely approximates reality and can be provided in real-time.

In a method of demodulating and decoding an encoded interleaved signal, a received encoded interleaved signal is demodulated, thereby producing soft-decision demodulated output words. Thereafter, the soft-decision demodulated output words are de-interleaved and scaled, thereby producing de-interleaved and scaled words. The scaling is performed for a plurality of successively demodulated output words at a time, thereby applying a scale factor that is substantially constant over the entire span of an interleaving frame. The de-interleaved and scaled words are word-length-reduced words. Finally, the de-interleaved and scaled words are decoded.

In a method of demodulating and decoding an encoded interleaved signal, a received encoded interleaved signal is demodulated, thereby producing soft-decision demodulated output words. Thereafter, the soft-decision demodulated output words are de-interleaved and scaled, thereby producing de-interleaved and scaled words. The scaling is performed for a plurality of successively demodulated output words at a time, thereby applying a scale factor that is substantially constant over the entire span of an interleaving frame. The de-interleaved and scaled words are word-length-reduced words. Finally, the de-interleaved and scaled words are decoded.

The invention discloses a preparation method for hollow carbon nanospheres, comprising: 1) placing a phenol in water, adjusting the pH value, adding an aldehyde, and stirring the solution at a certain temperature for a period of time; 2) adding an etchant to the reaction system and performing stirring at a certain temperature to obtain an intermediate product through selective removal of parts with low polymeric properties in the polymer by using the solubility difference between internal substances for different solvents; 3) calcining, in an inert or a reducing atmosphere, the intermediate product obtained in Step 2), and cooling the substance, thereby completing preparation of the hollow carbon nanospheres. In addition, by using the property that the phenolic resin is capable of in-situ polymerization on different nanoparticle surface, on one hand, a multi-layer hollow structure can be made through multiple times of coating and layer-by-layer corrosion; and on the other hand, different nanoparticles can be in-situ packaged in a cavity, thereby making a core-shell or yolk-core structure.

The invention provides a three-dimension mesh model copyright verification method, which comprises the following steps that S1, light holographical encryption copyright watermark information is generated; S2, a three-dimension mesh model is preprocessed; S3, a model geometrical characteristic matrix is built in a cylindrical coordinate system; S4, the geometrical characteristic matrix is subjected to QR decomposition to embed copyright watermark information; S5, the three-dimension mesh model embedded with the copyright watermark information is issued on public information platforms such as Internet; S6, the obtained three-dimension mesh model to be detected is subjected to pre-processing for carrying out QR decomposition on the geometrical characteristic matrix to extract a copyright encryption information grey-scale map, a copyright two-value watermark image is obtained through Fourier inversion and filtering by a two-order Butterworth high pass filter, and the copyright ownership of the three-dimension mesh model can be judged through human eye identification. The method belongs to an air space blind watermark algorithm, higher robustness is realized, and the obvious problems that the existing three-dimension mesh model copyright verification method can be easily cracked and copied, and the copyright anti-fake certification cannot be conveniently or effectively carried out are solved.

The invention relates to a quick and efficient non-template agent hydro-thermal synthesizing method. The system can synthesize an alpha-molybdenum trioxide nanometer rod and a high-density echinoid molybdenum oxide based nanometer materials. Molybdenum peroxide acid prepared from molybdenum trioxide and aqueous hydrogen peroxide solution is used as a precursor, is produced into scattered alpha-molybdenum trioxide nanometer rod by hydro-thermal synthesis at a temperature of between 80 and 180 DEG C, and is produced into the peroxide modified molybdenum oxide hydrate by hydro-thermal synthesis at a temperature of between 65 and 75 DEG C. The hydrate is a multiscale structure; a nanometer thin slice, a micron prism and a nanometer rod-shaped structure unit are divergently assembled into a micron-size high-density echinoid structure. The hydrate is roasted to obtain high-density echinoid alpha-molybdenum trioxide. Modulation of the synthesizing condition can realize fine adjustment for appearance of the nanometer rod, the micron-size echinoid structure and the structure unit thereof. The method uses raw materials with low cost, has the advantages of simple technical process, controllable conditions and the like, and can promote research and application of the molybdenum oxide in the fields of sensors, field transmission, electrode materials and so on.

The invention relates to an Au@SiO2 mesoporous composite nanomaterial and a preparation method thereof. Tetraethoxysilane is adopted as a silicon source, cetyl trimethyl ammonium bromide (CTAB) is adopted as a structure-directing agent, ethyl acetate (EA) is adopted as a co-template, water and ethyl alcohol are adopted as a cosolvent, CTAB and other residual organic matter are removed through acetone, 3-aminopropyl triethoxy silane (APTES) is modified to obtain SiO2, then a water solution of SiO2 of HAuCl4 is reduced through sodium borohydride (NaBH4), and then the nanomaterial with Au@SiO2 mesoporous composite nanoparticles is obtained, wherein the nanomaterial is uniform in appearance, and parallel open-framework structures and radial open-framework structures coexist. It can be seen from a TEM picture that the prepared Au@SiO2 mesoporous composite nanomaterial is provided with the parallel open-framework structures and the radial open-framework structures, the grain size of the SiO2 nanoparticles is about 150 nm, and Au nanoparticles are uniform in size and even in distribution. The Au@SiO2 mesoporous composite nanomaterial prepared through the method has potential application prospects in the fields of catalyzing, biomedicine and the like.

The invention discloses a preparing method of nanometer cobalt oxide, which comprises the following steps: (1) dissolving bivalent soluble salt in the water or alcohol or composite solvent of water and alcohol; obtaining the solution with bivalent cobalt ion; (2) adding certain quantity of ammonia in the bivalent cobalt ion solution; blending evenly; refluxing and heating in the reactor; or transmitting into autoclave to do close heat; (3) separating sediment; washing; drying; obtaining nanometer material of black cobalt oxide with different size or shape; realizing controllable equipment of nanometer cobalt oxide within certain scale.

The invention discloses a method for manufacturing carbon microspheres by using waste macromolecules as raw materials. The method is characterized by comprising the following steps of: sealing 75 to 300g / L of waste polyester, polypropylene or polyethylene and 300 to 600g / L of dry ice into a stainless steel autoclave based on the volume of the autoclave, heating the mixture to between 500 and 650 DEG C, preserving the heat for 180 minutes, and then cooling the mixture to room temperature to obtain micro-scale carbon spheres; annealing the prepared micro-scale carbon spheres for 1 hour under the vacuum condition of 1,500 DEG C to further obtain laminated carbon microspheres; and performing oxidation treatment of a Hummers method on the laminated carbon microspheres for 24 to 72 hours to obtain ellipsoidal laminated graphite carbon oxide microspheres. The method can improve the yield of solid carbon and greatly reduce the formation of carbon dioxide, and is suitable for industrialized production; and the obtained product has wide application prospect in the fields of adsorption and desorption, lithium ion batteries, catalyst carriers and the like.

The invention discloses a preparation method of a hydroxyl magnesium silicate nanotube. The hydroxyl magnesium silicate powder with a nanotube form can be prepared by the technical scheme provided by the invention. The hydroxyl magnesium silicate with a nanotube structure is added to a lubricating agent, so that the friction wear property in mechanical movement can be greatly improved by a rolling friction form, the surface hardness, the fineness and the wear-resisting property of the metal are improved, and the service life of mechanical equipment is prolonged.

An apparatus and method for simulating the behavior of the drive system and the mechanism of machine tool or production-line machine by use of mathematical models of the drives and the mechanisms of the driven mechanical elements of the machine are disclosed. Preferably actual values for regulated and unregulated axes are calculated at the same time using NC- and PLC-models, respectively by an auxiliary computer using desired values provided by a digital controller. The actual values are then supplied to a mechanism model, preferably a geometric kinematic model, which produces a state signal that is fed back to the digital controller, preferably in real time. The result is an efficient, easy and cost-effective simulation that closely approximates reality and can be provided in real-time.

The invention discloses a method for preparing a metal-oxide compound nano catalyst by molecular layer deposition. The method comprises the following steps: placing a sample loaded with a metal A precursor into a reaction cavity of molecular layer deposition equipment; feeding a precursor of B, multivariate isocyanate and polyamine into the cavity in sequence to generate layer-by-layer monomolecular layer reaction, and covering a compound of the precursor of A by a B-containing organic-inorganic compound membrane; growing layer by layer, changing the cycle number to adjust the thickness of a B-polyurea hybrid membrane; and removing an organic part of the compound by thermal treatment, reducing to realize high-dispersion mixing of the metal A and nano particles of an oxide B, and forming an interface with a large number of metals A and oxides B. The obtained metal-oxide interface controllable material is higher in performance in catalytic hydrogenation, catalytic oxidation and the like. The method is easy to operate, and the interface site can be adjusted according to the deposition cycle number.

The invention relates to a production device of graphene. The device is characterized in that the device comprises a reaction kettle (1) and a motor (2), the motor is mounted at the top of the reaction kettle (1), the output end of the motor (2) is connected to a shearing machine (3), the top of the reaction kettle (1) is provided with a feeding port (4), a pressure gage (5) and a temperature meter (6), the inner wall of the reaction kettle (1) is provided with shearing slots (7), a material discharging port (8) is disposed in the middle and lower part of the reaction kettle (1), and a jacket (9) is disposed outside the reaction kettle (1) and is provided with a hot-medium inlet and an outlet. When the device is used for graphene production, the yield is high, the cost is low and the prepared graphene is high in quality.

The invention discloses a graphite phased carbon nitride (g-C3N4) nano-ring material and its preparation method, and belongs to the technical field of nanometer material preparation. The g-C3N4 nano-ring material is a ring structure, wherein the diameter of an outer ring is 20-1000 nm, the height of the outer ring is 20-200 nm, and the diameter of an internal circular hole is 10-800 nm. The preparation method includes steps of using melamine as a precursor and silicon dioxide nanosphere as a template; making the heated and sublimated precursor enter a high-temperature zone under the blowing of carrier gas to perform the heat polycondensation reaction; self-assembling a heat polycondensation product on the surface of the silicon dioxide nanosphere to form a g-C3N4 nano-ring; after cooling, removing the template by etching reagent, and drying the product to acquire the g-C3N4 nano-ring material. Compared with volume phase g-C3N4 formed by the heat polycondensation method, the g-C3N4 has higher specific surface area, more excellent photo-induced electron-cavity separating ability and better conductivity; thus the g-C3N4 can be used for photocatalysis hydrogen production, photocatalysis carbon dioxide reduction, and photocatalysis degraded organic matters, and other domains, and also can be used as carrier loaded catalyst or drug; therefore, the g-C3N4 nano-ring material has wide application prospect in energy source, environment and medicine domains.

The invention relates to a device and method for preparing nanometer oxide nesa by ultrasound rapid deposition method, which comprises an atomization case, a heat reaction chamber and line pipes, wherein the heat reaction chamber is provided with a glass substrate on the bottom, the SnO2 : F solution is atomized by means of supersonic spray method, the nano level particles are sprayed homogeneously onto the glass substrate through an atomization nozzle.

A preparation method for a copper-zinc-tin-sulfur nano powder material belongs to the technical field of inorganic chemical materials. The preparation method comprises the following steps of: selecting alkanolamine or polyalcohol as solvent and dissolving a compound containing Cu, Zn and Sn with the mol ratio of Cu to Zn to Sn being 2:1:1 into the solvent; then dissolving a simple substance S of which the molar weight is two times that of Cu into another alkanolamine or polyalcohol solvent; and mixing two liquid systems, stirring under the protection of inert gas, heating to 200-280DEG C, carrying out reflowing reaction for 4-10 hours and cooling to room temperature and taking black powder on a lower layer for centrifugal separating, washing and drying to obtain copper-zinc-tin-sulfur compound nano powder. The preparation method disclosed by the invention can be used for preparing the copper-zinc-tin-sulfur compound nano powder material with the advantages of nanoscale, uniformity in size, favorable dispersity and high phase purity and has the characteristics of high efficiency, high yield, low cost, favorable repeatability, simpleness in operation and easiness in control. The copper-zinc-tin-sulfur compound nano powder material prepared by the preparation method disclosed by the invention can be used for preparing slurry of a solar battery absorbing layer.

The invention discloses a method for inducing the wettability changes of a super-hydrophobic film through a solvent. The method comprises the steps that a film is subjected to hydrophobization treatment to obtain the super-hydrophobic film; a water drop is dropwise added on the super-hydrophobic film, and the solvent for inducing the wettability changes of the prepared super-hydrophobic film is dropwise added over or at one side the water drop; after the solvent is naturally volatilized, the water drop is in a hydrophilic or hydrophobic state, and then the wettability of the super-hydrophobic film changes, wherein one of volatile organic solvents such as dichloromethane, dichloroethane, n-hexane and tetrahydrofuran is adopted as the solvent for inducing the wettability changes of the prepared super-hydrophobic film. The method that the wettability changes is induced by the solvent can be applied to liquid drop driving and has the important significance on the aspect of regulating the contact mode of liquid and electrodes in electro-deposition.

The present invention discloses a production method for ferric phosphate nanometer powder with a characteristic of controllable particle size. In the prior art, battery grade ferric phosphate production processes commonly have disadvantages of large size, impure phase, complex process, high production cost and the like, and especially the phase carries a certain proportion of crystal water so as to directly cause instable phase, instable performances and the like of the lithium iron phosphate powder synthesized at the late stage. The synthesis process comprises: preparing a phosphate organic / pure water mixing base solution in a certain pH range, adding a plurality of additives, adding an iron salt solution at a constant temperature in a stepwise manner, adjusting the pH value of the solution during the adding process with a dropwise manner, carrying out constant temperature stirring for a certain time, carrying out suction filtration, washing and drying on the obtained product, and finally carrying out annealing for a certain time at a temperature of 300-600 DEG C to obtain the ferric phosphate nanometer powder. The ferric phosphate nanometer powder produced by the method has characteristics of controllable particle size, controllable components, simple process, low cost, high powder activity, easy production enlargement and high market competitiveness.

The invention provides a preparation method of novel and green mono-dispersive silicon dioxide nanospheres. The preparation method comprises the following steps: preparing a O / W water / ethanol / dichloromethane microemulsion with a surfactant; fully dissolving TEOS under action of ultrasonic treatment and stirring in spherical oil kernels of the O / W water / ethanol / dichloromethane microemulsion with the surfactant; then under catalysis of ammonia water, carrying out hydrolytic polycondensation on TEOS; after reaction, carrying out centrifugal separation; and washing a solid component with a polar solvent for many times to obtain the mono-dispersive silicon dioxide nanospheres, and distilling the residual liquid component to collect ethanol and dichloromethane. According to the method, the operation is simple, the cost is low, an environment-friendly effect is achieved, the system can be used repeatedly, and the efficiency is high. The prepared SiO2 nanospheres are uniform in dimension, andhave universality and scaled production value. The preparation method is simple in step, convenient to operate and high in practicality.

The invention discloses a preparation method of KNbO3 nano solid solution with adjustable optical band gap. The preparation method is as follows: adding citric acid monohydrate into deionized water for completely dissolving, then adding basic nickel carbonate, heating and stirring to form a transparent solution A; adding niobium oxalates into the deionized water for completely dissolving to form a solution B; slowly adding dropwise the solution B into the solution A, fully stirring, successively dissolving anhydrous potassium carbonate and barium carbonate into a mixed solution of the solution A and the solution B for full reaction and stirring to form a transparent solution C; finally adding ethylene glycol, and fully stirring to form a solution D; heating the D solution for evaporation and promotion of citric acid and ethylene glycol esterification, drying to form a dark yellow solid precursor; grinding the precursor, and calcining in air atmosphere to eventually obtain the nano solid solution with the chemical formula of [KNbO3] 1-x [BaNi1 / 2Nb1 / 2O3-Delta] x. The product exhibits better photocatalytic effect in visible region.

The invention relates to a Co-modified metal organic framework-derived ZrO2 / C electromagnetic wave absorbing material, and a preparation method and an application thereof. The electromagnetic wave absorbing material is of a three-dimensional network structure formed by interweaving one-dimensional fibers. The fiber is composed of a carbonaceous matrix, ZrO2 and Co nanoparticles. The Co nanoparticles are embedded in the surface of the carbonaceous matrix uniformly distributed by ZrO2. The method comprises the steps that 1, a cobalt source, a zirconium source, an anhydrous acetic acid organic ligand and DMF are processed into a solvothermal solution, the organic ligand containing a carbon source, an MOF precursor is obtained after solvothermal reaction, the MOF precursor is washed and dried,then the MOF precursor is treated with the cobalt source, and cobalt source composite MOF is obtained; and (2) the compounded MOF precursor is placed in a protective atmosphere to convert cobalt ionsin a cobalt source into elemental cobalt, a zirconium source into ZrO2 and an organic ligand into a carbon matrix, thereby obtaining the catalyst. According to the preparation method disclosed by theinvention, ZrO2, Co and C are effectively subjected to nanoscale compounding, so that the prepared material has excellent performance.

The invention relates to a high-modulus organic-inorganic hybridized polyimide film and preparation and application thereof, in particular to the technical field of organic-inorganic hybridizing polymer materials. In particular, a polymer film in which 0.1 to 60 percent of inorganic nanometer particles are dispersed has high modulus, low shrinkage and superior physical-chemical performance, and particularly has tensile modulus which is larger than 5Gpa. Designed solvent type nanoparticle dispersion liquid can be added into a polymer composition efficiently and conveniently, and inorganic nanometer particles are uniform in size, and are stable in dispersion; the high-modulus organic-inorganic hybridized polyimide film is an organic-inorganic hybridized polymer material which has the advantages of high modulus, low shrinkage, superior chemical performance and superior electric performance.

The invention provides a preparation method of a Cu-In-Ga-Se-S nano powder material, belonging to the technical field of inorganic chemical materials. The preparation method comprises the following steps: based on alkanolamine with a boiling point large than or equal to 180 DEG C as a solvent, dissolving Cu, In and Ga compounds into the alkanolamine in a mole ratio of Cu: (In+Ga) of 1: (1-1.5); then dissolving Se and S in the alkanolamine, wherein the sum of molar weights of Se and S is twice as heavy as molar weight of Cu; and subsequently, mixing two solutions, stirring under the protective condition of inert gas, heating to 200-280 DEG C for refluxing, maintaining the reaction for 4-10 hours and then stopping heating and stirring, cooling to room temperature, centrifuging, washing and drying the black powder on the lower layer, so as to obtain the Cu-In-Ga-Se-S nano powder material. By using the preparation method in the invention, the Cu-In-Ga-Se-S nano powder material which is in a nano grade and has uniform scale, good dispersibility and high phase purity can be prepared, the whole preparation process is high in efficiency and low in cost, and operation is simple and is easy to control. The Cu-In-Ga-Se-S nano powder material prepared by the method in the invention can be used in a solar battery as an absorption layer material.

The invention discloses urchin-like graphene and a preparation method thereof, and relates to the field of graphene material preparation. The method includes the steps that a nickel salt and a reducing agent react under the alkaline condition, and an urchin-like three-dimensional nickel substrate is formed through self-assembly; graphene is deposited on the urchin-like three-dimensional nickel substrate with the chemical vapor deposition technology; acid is added to remove the nickel substrate, and then the urchin-like three-dimensional graphene is obtained. The urchin-like three-dimensional graphene has a good dispersing type, and the problems of stacking, porosity, unstable structure and the like are effectively prevented. The preparation process is simple, the condition is mild, the rawmaterial source is wide, and the urchin-like graphene is suitable for mass production and has broad application prospects.

The invention discloses equipment and a method for preparing microcapsules by liquid-liquid electronic micro-jet atomization. The equipment is provided with a finished product microcapsule reaction collector, wherein a working liquid box, a metal capillary, solidifying liquid and a base electrode are arranged in the inner cavity of the collector; a charging electrode is arranged on the bottom surface in the working liquid box. The method is characterized in that preparation liquid is ejected in an electrostatic atomized drop-shaped mode from the metal capillary under the actions of a high-voltage electric field and uniform pressure, and target droplets with small particle diameters are formed in the solidifying liquid and are solidified into capsules, wherein the particle diameters of the formed microcapsules are uniform in distribution and are high in monodispersity; when the target droplets of a lower layer are formed, the working liquid box, the charging electrode and the metal capillary are integrally moved upward, the preparation liquid forms another layer of droplets in the solidifying liquid, and finally a plurality of layers of droplets which are distributed uniformly are formed. The preparation liquid is atomized and dispersed in the solidifying liquid, so that the drift of the atomized droplets in a falling process can be overcome effectively; the atomized droplets can be prevented from being polluted by other media.

The invention provides a composite powder particle of a submerged arc surfacing high boron alloy and an application method thereof, 6-14 meshes of composite powder particle made by the steps of powdercomponent dry mixing, soaking mixed powder in pure water to be mixed and wetted, rotary bonding granulation, low temperature sintering, sieving and the like is prefabricated in a weld bead, and a solid welding wire is used as an arc carrier for submerged arc surfacing, so that the composite powder melt and the solid welding wire droplet are fused into an integrated surfacing weld pool. Under theaction of arc heat, most of the boron carbide and metal chromium components contained in the composite powder particle are subjected to in-situ metallurgical reaction to form a primary M2B hypereutectic high boron alloy with a large length-width ratio and a microhardness average reaching 1622 HV. The high boron alloy prepared by the composite powder particle has excellent abrasion resistance and high toughness, and can be used for submerged arc surfacing welding wear-resistant alloy layers of parts under a low stress abrasive wear condition, and can protect the open arc welding directly.

The invention belongs to the technical field of an electronic device which relates to a side wall electrode of a big length-diameter ratio electrodes and a preparation method thereof. The length directions of the big length-diameter ratio electrodes are mutually parallel and are parallel to a base piece; if the layer number of the electrodes is larger than two, the layers are stacked and arrayed, solid insulation materials are filled between every two layers of big length-diameter ratio electrodes, the big length-diameter ratio electrodes are different parts which are mutually electric insulated in a length direction, a gap exists between every two parts, and gaseous or liquid insulating materials are filled in the gap. The method comprises the following steps: an electrode material film is deposited on the surface of the base piece, and an big length-diameter ratio electrode array is formed by using a graph transferring method; if the side wall electrode is a single-layer electrode, a graph which contains the electrode gap is directly formed; if the side wall electrode is a multilayer electrode, the solid insulation materials are deposited on the surface of the electrode material, a stacking structure of multilayer big length-diameter ratio electrodes is prepared, and the electrode gap is formed again. The invention has a higher electric field reinforcing coefficient, and the polarization characteristics of other electric fields can be optimized in a more controllable mode.

The invention provides a novel green single-dispersed silica nanoparticle preparation method. The method includes: preparing an O / W-type water / ethanol / dichloromethane surfactant-free microemulsion; completely dissolving tetraethoxysilane (TEOS) in a spherical 'oil core' of the O / W-type water / ethanol / dichloromethane surfactant-free microemulsion prepared in the first step under the action of ultrasound and agitation, subjecting the TEOS to hydrolytic polycondensation and performing centrifugal separation after reaction; washing solid components with a polar solvent for multiple times to obtain single-dispersed SiO2 nanoparticles, and distilling remaining liquid components to collect ethanol and dichloromethane. The method is simple in operation, low in cost, environment friendly, reusable in system and high in efficiency; the prepared SiO2 nanoparticles are uniform in size, and universality and scale productive values are achieved; the method is simple in step, convenient in operation and high in practicability.