230results about How to "Uniform shape and size" patented technology

The invention provides an II-II-VI alloy quantum dot, as well as a preparation method and application thereof. The preparation method comprises the steps of S1, reacting a precursor containing secondII group elements and a precursor containing first VI group elements to form an II-VI semiconductor nanocluster; S2, mixing the II-VI semiconductor nanocluster and the precursor containing the first II group elements, and obtaining a first system containing the II-II-VI alloy quantum dot through cation exchange and in-situ growth. The II-VI nanocluster formed at the beginning of nucleating is located at a nanocrystalline nucleation and growth intermediate state and is small in size, the precursor containing the first II group elements is added for carrying out cation exchange, first II group element atoms easily enter the innermost of the II-VI nanocluster so as to form an II-II-VI nanocluster similar to an alloy, and during the continuous growth process, the first II group element atoms are gradually outwards diffused to the whole particle so as to obtain the narrow half-width alloy quantum dot.

The invention provides an inorganic metal halide perovskite nanosheet preparation method. Cesium lead halide CsPbX3 perovskite nanosheets are prepared by means of a high-temperature thermal injection method. According to the high-temperature thermal injection method for synthesis, a metal halide precursor in an oil system is in reaction under inertial gas shielding to produce metal halide perovskite nanosheets, and the size of the perovskite nanosheets is controlled by change of reaction temperature and time. The synthesized nanosheets have the advantages of shape uniformity, high light emitting efficiency, high stability, simplicity in synthesis and high development value.

The invention belongs to the technical field of molecular sieves and particularly relates to a cubic or sheet-shaped nano SAPO-34 molecular sieve and application thereof in conversion, separation and absorption of all kinds of hydrocarbons. The dimension range of the molecular sieve is within 20-300nm and is rapidly prepared by using tetraethyl ammonium hydroxide as template agent, mixing the tetraethyl ammonium hydroxide with an aluminum source, a silicon source and a phosphorus source and adding specific solvent to control gel concentration through the traditional hydrothermal or microwave heating method. The nano-scale SAPO-34 molecular sieve synthesized by adopting the method has the characteristics that the cost of raw materials for gel is low, the production speed of the molecular sieve is rapid, the preparation time of crystallized start materials is short, the reaction energy consumption is low, the yield of the molecular sieve is high, the catalytic application life is long and the catalytic effect of the molecular sieve in catalytic reaction can be obviously improved.

The invention relates to a rare earth doped lithium yttrium fluoride nanometer material and a preparation method and application thereof. A modified high-temperature coprecipitation method is adopted to synthesize the rare earth doped lithium yttrium fluoride nanometer material with upper conversion/lower transfer luminescence, at the same time, epitaxial growth is conducted on the basis of a core, a mono-layer core-shell structure nanometer material which is uniformly covered can be obtained, and a lithium yttrium fluoride based multi-layer core-shell nanometer material is further prepared. The three prepared and obtained materials are good in monodispersity, uniform in particle size and excellent in luminescent property, after acid pickling treatment, water-soluble nanometer particles can be used for biological detection and biological imaging.

The invention relates to a synthesizing method of inorganic perovskite nanosheets. The method includes: adding the precursor solution of cesium into the precursor solution of lead halide, performing ultrasonic treatment for 10-30 minutes to obtain a mixed solution, transferring the mixed solution into a reaction kettle, performing reaction under 60-150 DEG C for 30-420 minutes, and naturally cooling to obtain reactants; performing centrifugal processing and washing to obtain the inorganic perovskite CsPbX3 nanosheets. The method has the advantages that the method is simple to operate and does not need harsh experiment conditions, and the prepared nanosheets are uniform in size, high in controllability and high in yield, and the quantum efficiency of the nanosheets reaches up to 48%.

The invention discloses a preparation method of an alpha phase cobaltous hydroxide nanosheet for an oxygen evolution reaction. A cobalt source compound and an alkaline reagent are dissolved into hydrophilic solutions, reflux condensation under microwave heating is carried out after even mixing, natural cooling to the room temperature is carried out, separation is carried out after centrifugal washing, and the alpha phase cobaltous hydroxide nanosheet is obtained after vacuum drying. According to a preparation method, the microwave heating reflux condensation manner is adopted, the preparation method is simple, easy to operate, low in cost and environment-friendly, no special equipment is needed in the overall reaction process, industrial production is facilitated, and finally the obtained product is higher in quality. The alpha phase cobaltous hydroxide nanosheet prepared through the method can have the beneficial effects of being high in material electrical conductivity, many in active site, high in electrocatalytic activity and the like. The material prepared through the method is an ideal oxygen evolution reaction catalytic material with wide commercialization application prospect.

The invention discloses a method for synthetizing high-stability metal halide perovskite/lead sulfide heterostructure nanocrystals. The method comprises the following steps: firstly mixing lead halide with reactive solvent oleic acid, organic amine with long alkyl chains and octadecene in the presence of an inert gas so as to completely dissolve lead halide; then heating a mixed solution to 160-200 DEG C, rapidly injecting a caesium precursor, and reacting to generate CsPbX3; cooling to room temperature, then sequentially injecting a sulphur precursor and a lead precursor, and stirring for reaction, thereby finally obtaining the CsPbX3/PbS heterostructure nanocrystals. The synthetized CsPbX3/PbS heterostructure nanocrystals are uniform in appearance; the synthesis method is simple; due to epitaxial growth of lead sulfide, the perovskite performance stability is improved, and the CsPbX3/PbS heterostructure nanocrystals are enhanced in light-emitting efficiency and are beneficial to later-stage photoelectric device assembly.

The invention relates to a method for preparing multi-shape controllable nano nikel-cobalt spinel oxide. The method includes the steps that nickel nitrate and cobalt nitrate are dissolved in anhydrous ethanol according to the cobalt-nickel atom ratio to form a solution A; oleylamine is dispersed in an ethanol solution to form a solution B, and the solution B and the solution A are mixed to obtain a mixed solution; the mixed solution is fully and evenly stirred and moved into a dynamic reaction kettle, H2 is replaced in a sealed mode, pressure intensity of H2 is adjusted to 6-15 bar after replacement, and a steel cylinder air outlet valve is closed; the stirring speed of the dynamic reaction kettle is adjusted to 400 r/min, temperature is set to be 150 DEG C, and reaction is carried out for 10 h; a product is cleaned through ethanol and other nonpolar solvents respectively, centrifugal separation is carried out, and a sediment precursor is obtained through drying at the temperature of 60 DEG C; the temperature of the obtained sediment precursor rises in an air atmosphere at the speed of 10 DEG C/min, and the sediment precursor is heated to 200-400 DEG C and kept warm. According to the method, procedures are few, materials are easy to get and low in price, the procedures are safe, nikel-cobalt spinel oxide of different shapes can be obtained by changing a small condition in the procedures, and accordingly preparing of the controllable nano nikel-cobalt spinel oxide is achieved.

The invention provides an undifferentiated anti-aging amplification culture medium for human umbilical cord/adipose tissue-derived stem cells. The problem in the prior art that a serum-free medium used for culturing mesenchymal stem cells is easy to differentiate and easily causes aging and apoptosis of adult stem cells is solved. The undifferentiated anti-aging amplification culture medium for human umbilical cord/adipose tissue-derived stem cells comprises cell factors, vitamins and chemical small molecules, and the culture system comprises multiple chemical small molecules and biomacromolecules and has the effects of improving physiological metabolism and proliferation and growth potential of cells, resisting oxidative stress response, scavenging free radicals, preventing DNA mutation, protecting mitochondria, reducing molecular wastes in the cells and activating longevity genes and telomerase.

The invention discloses a method for preparing silver nanowires. The silver nanowires are prepared controllably by the self-assembly characteristic of micelle of amphiphilic hyperbranched polymer. The method comprises the following specific steps of dissolving or dispersing the amphiphilic hyperbranched polymer in polyhydric alcohol; adding halogenous inorganic salt or sulfurated inorganic salt in the mixture; adding silver salt in the mixture after the halogenous inorganic salt or sulfurated inorganic salt is dissolved in the mixture completely; placing obtained mixed solution in a sealed reaction kettle; performing constant-temperature reaction at a certain temperature in a range of 120-240 DEG C; naturally cooling down a reaction product to obtain raw products of silver nanowires; and washing the raw products by using organic solvent and centrifugally separating the raw products to obtain the silver nanowires. A one-kettle solvothermal method is used, the amphiphilic hyperbranched polymer is used for preparation of the silver nanowires, and the silver nanowires with uniform sizes and morphologies can be obtained. The steps of the method are simple and are easy to operate; the controllability and the reproducibility are high; and the silver nanowires are easily produced in batches.

The invention belongs to an inorganic mesoporous material area, in particular to a preparation method of a controllable silica hollow sphere material in a certain diameter range. The anionic surfactant sodium dodecyl sulfonate (SDS) controls the synthesis of spherical wall, which is provided with mesoporous channels and narrow distribution of diameter. The invention uses block copolymer and sodium dodecyl sulfonate as mixing template; with the addition of silicon source, the sol is formed after mixing; under the acid condition, through the agitating and aging treatment, after hydrothermal process, filtering and drying, the template is calcined to obtain silica hollow sphere with the mesoporous channel. Through changing the content of SDS, the synthesis of different size of silica hollow spheres with the mesoporous channel can be controlled. The invention has a simple process and a low cost; the mesoporous shell thickness and the pore diameter of the prepared silica hollow sphere with the mesoporous channel can be controlled in a large range; the invention is beneficial to the internal and external transmission of guest molecules; the invention also improves the reserves of guest molecules, which realizes the controlled release effectively.

The invention relates to a micron/nanoscale BiOCl film material and a preparation method thereof. The film material comprises a substrate. A layer of bismuth metal film is deposited on the substrate; a layer of BiOCl film consisting of two-dimensional BiOCl nano sheets is formed by using the bismuth metal film as a raw material. The thickness of the BiOCl film is between 30nm and 2 mu m. The preparation method for the micron/nanoscale BiOCl film material comprises the following steps: depositing a layer of bismuth metal film on the substrate by adopting physical vapor deposition; soaking in solution containing H2O2 and Cl- by a wet method, adjusting the volume percentage of H2O2 to 1 to 99 percent and the concentration of Cl- to between 0.01 and 2 mol/L to ensure that the pH value of the mixed solution is in a range from 0.5 to 7, keeping the temperature of a reaction system between 20 and 80 DEG C, and soaking for 1 to 60 minutes; and obtaining the micron/nanoscale BiOCl film material with different features after washing. The preparation method for the micron/nanoscale BiOCl film material has the advantages of simple and controllable process, uniform dimension and feature of the product, short production cycle, low cost and suitability for large-scale industrial production. The BiOCl film material has wide application prospects in photocatalysis, optoelectronic thin-film devices, nanocoatings, pearl pigments, and other fields.

The invention discloses a preparation method of monodispersed selenium doped nano hydroxyapatite. The method is as below: adding soluble calcium salt, soluble phosphate salt and selenite in a mixed system of polyethylene glycol, ethanol and oleic acid; and conducting one-step hydrothermal reaction to obtain selenium-doped nano hydroxyapatite with good dispersion. By controlling the amount of selenate radical, nanorods and nano needles selenium-doped hydroxyapatite can be prepared. The hydroxyapatite nanorod or nanoneedle prepared by the invention can be used for repairing material, coating material and plastic filling material for patient bone defect, and has good application prospect.

The invention relates to a carbon cloth load Ni(S0.41Se0.59)2 nanosheet array and a preparing method thereof, and belongs to the technical field of inorganic nanomaterial preparing. A carbon cloth load Ni(OH)2 nanosheet array serves as a front driving body to be simultaneously vulcanized-selenized to prepare the carbon cloth load Ni(S0.41Se0.59)2 nanosheet array. The preparing method comprises the specific steps that firstly, nickel nitrate, ammonium fluoride and urea are used as reactants, the carbon cloth load Ni(OH)2 nanosheet array which serves as the front driving body is prepared through a hydrothermal method, further, sulfur powder and selenium powder mixture with the mass ratio of 1:3 is used to simultaneously vulcanizing and selenizing the front driving body under the protection of nitrogen to prepare the carbon cloth load Ni(S0.41Se0.59)2 nanosheet array.

The invention relates to a method for synthesizing caesium-lead-halide Cs4PbX6 nanocrystals. The method comprises adding a precursor solution of caesium into a precursor solution of lead halide at theroom temperature, carrying out ultrasonic mixing to obtain a uniform mixed solution, transferring the mixed solution C into a reactor, carrying out a reaction process at 80-150 DEG C for 30-200min, carrying out natural cooling to obtain a reaction product, carrying out centrifugation, and washing and drying the products to obtain final product Cs4PbX6 nanocrystals. The method is easy to operate and is free of harsh operating conditions. The Cs4PbX6 nanocrystals have the characteristics of strong controllability, uniform morphology, high purity and high yield.

The invention discloses a preparation method of an oxygen evolution reaction catalyst material iron-nickel hydrotalcite structure nanosheet. The method comprises the steps of dissolving an iron source compound and a nickel source compound into a hydrophilic solution; adding an organic sodium salt and an alkaline reagent and further stirring to form a clear solution; and carrying out reflux condensation under microwave heating, naturally cooling the solution to a room temperature, carrying out centrifugal washing and then carrying out separating and vacuum drying to obtain the iron-nickel hydrotalcite structure nanosheet. By adopting the method of reflux condensation under microwave heating, the preparation method is simple, easy to operate, low in cost and friendly to environment; special equipment is not needed in the overall reaction process; industrial production is facilitated; and the finally obtained product is relatively high in quality. According to the iron-nickel hydrotalcite structure nanosheet prepared by the method, the advantages that the material conductivity is high, active sites are multiple and the electrocatalytic activity is high can be simultaneously achieved. The prepared material is an ideal oxygen evolution reaction catalytic material with a wide commercial application prospect.

The invention relates to a photosensitizer nanoparticle as well as a preparation method and application thereof. The photosensitizer nanoparticle comprises components of photosensitizer molecules and regulation and control molecules for conducting regulation and control on the composition structure of the photosensitizer; the preparation of the photosensitizer nanoparticle is realized through self-composition of the photosensitizer molecules and the regulation and control molecules. The photosensitizer nanoparticle has the advantages that the size is controllable, the distribution is uniform, and the medicine loading capacity are high; the preparation method is simple and quick, and does not need to use any toxic solvent or additive; the photosensitizer nanoparticle can be applied to preparation of medicines for tumor positioning image formation and photodynamic therapy, has the characteristics of being high in biocompatibility and high in tumor tissue gathering, and has excellent application prospects when being used as the anti-tumor and photodynamic therapy medicine.

The invention discloses three-dimensional flower-shaped bismuth ferrite powder and a preparation method thereof. The preparation method comprises the following steps: taking Bi(nO3)3.5H2O and Fe(NO3)3.9H2O as starting materials, preparing blocky bismuth ferrite powder by adopting a hydrothermal method, then mixing the bismuth ferrite powder, a corrosive solvent, a reducing agent and a complex agent under the protective atmosphere, and obtaining three-dimensional porous bismuth ferrite flower balls by adopting a one-step corrosion method. According to the invention, a thick flaky Bi2Fe4O9 powder raw material is prepared by adopting the hydrothermal method, grains are uniform in size and shape and are better in dispersibility, a corrosion technology is adopted, preparation technological operation is simple, and the period is short; and the prepared flower-shaped bismuth ferrite has the diameter being about 1-2mu m, sizes are uniform, a specific surface area is relatively large due to a porous structure, and performances of all the aspects are respectively improved.

The invention relates to a cake forming method of high-purity alumina powder, belongs to the technical field of chemical machining forming methods, and in particular to an alumina cake forming method. The cake forming method comprises the steps of preforming, vacuum sealing, isostatic cool pressing, high-temperature sintering and the like. According to the invention, a mould made of a PP or tetra fluorine material is adopted, pollution caused by high-purity alumina by the traditional steel mould is avoided, a preformed cake obtained by through low-pressure pressing can ensure that the cake in the later-stage isostatic cool pressing does not easily deform like the original organic mould due to a certain strength, thus the cake with uniform material and enough density is obtained. The cake subjected to the isostatic cool pressing has unchangeable purity after being sintered, and has uniform shape and size and density of commonly reaching 3.0-3.7g/cm<3>. The loading quantity during producing and loading of a downstream manufacturer of sapphire can be effectively increased.

The invention relates to a preparation method and application of a magnetic covalent organic framework material. The preparation method comprises the following steps: (a) preparing ferroferric oxide Fe3O4 magnetic nanoparticles by using solvothermal method and carrying out surface activation; and (b) coating the surfaces of the Fe3O4 magnetic nanoparticles with a TpBD covalent organic framework toobtain a Fe3O4@TpBD composite material, and applying the Fe3O4@TpBD composite material to enrichment detection of food hazard factors. The beneficial effects of the invention are that: the magnetic covalent organic framework material is successfully prepared, the synthesis method is simple, and the nano composite material is uniform in morphology and size, has a large specific surface area and aporous structure, and can be applied to enrichment detection of various food hazard factors such as food packaging material processing aids, sulfonamides and veterinary drugs, biotoxins and endocrinedisruptors.

The invention provides a hollow carbon sphere and a preparation method thereof. The preparation method comprises the following steps: 1) styrene compounds are subject to polymerization reaction in silica sphere dispersion in which an initiator and a stabilizer are dissolved to obtain silica spheres coated by a polystyrene layer; 2) the silica spheres coated by the polystyrene layer are subject tosulfonation reaction to obtain silica spheres coated by a sulfonated polystyrene layer; 3) the silica spheres coated by the sulfonated polystyrene layer are sintered to obtain silica spheres coated by a carbon layer; and 4) the silica spheres coated by the carbon layer react with alkali or acid, thus obtaining the hollow carbon spheres. The preparation method provided by the invention has the advantages that the used template spheres are cheap and can be obtained easily, the preparation process is simple, and industrial production can be realized easily.

The invention discloses a preparation method of a high-performance carbon-silicon composite hollow nano-sphere negative material. The method comprises the following steps: taking phenols, aldehydes and orthosilicate organic substances as raw material, preparing through a microwave method to obtain phenolic resin and silicon dioxide composite under the effect of the alkali catalyst and the surfactant; and then obtaining the silicon-carbon composite hollow nano-sphere through high-temperature carbonization and thermal reduction treatment. The preparation method disclosed by the invention is simple in process, convenient for operation, easy in raw material obtaining, low in cost and in favor of industrial production, the prepared material size and morphology are uniform, and the rich mesoporous structure is provided, the ion transmission distance is shortened, the ion diffusion rate of the material is improved, and the conductivity of the material is improved, so that the material has stable cycling and rate performance, and the preparation method has potential application prospect on the negative electrode aspect of the lithium ion battery.

The invention provides a preparation method of a CsPb2Br5 inorganic perovskite nanosheet, and belongs to the technical field of preparation of inorganic nano-materials. According to the invention, a precursor solution is dropwise added on a substrate, and then is sealed and stood in a glass pot with an anti-solvent so as to obtain the CsPb2Br5 inorganic perovskite nanosheet. The CsPb2Br5 inorganicperovskite nanosheet provided by the invention has uniform morphology dimension and good crystallization property; and the preparation of an oversized nanosheet with dimension of 120 mu m and thickness of 125 nm is realized. Meanwhile, the preparation method provided by the invention has the advantages of simple technology, low cost, easily available raw material, mild reaction condition, and canbe performed under normal temperature and normal pressure, and is conducive to realization of the industrial production of large-area perovskite nanosheets.

The invention provides a multi-component precious metal loaded type nano catalyst in which cobalt oxide is loaded to an oxide carrier, a preparation method and application thereof. The preparation method is characterized in that a coprecipitation method is carried out; precious metal crystal seeds are loaded on an alkaline cobalt carbonate nanoparticle precursor in an ethylene glycol system; the reacted product is centrifugally dried to obtain precious metal loaded type cobalt oxide nanoparticles. According to the preparation method, the precious metal loaded cobalt oxide with a heterostructure is synthesized, so that the essence and composition of active sites of the precious metal loaded type cobalt oxide nano catalyst are influenced; the prepared materials are loaded on the oxide carrier through a liquid-phase mixing method, so that the dispersing degree of the precious metal loaded type cobalt oxide can be improved, and moreover, the problem of high cost caused by previous metal can be reduced. The preparation method of such material is simple and easy to operate, consistent in shape, high in stability, and low in cost, and shows high methane low-temperature oxidizing activity while being applied to methane combustion reaction, and has a certain industrial application prospect.