653results about How to "Good crystal form" patented technology

The invention concerns arrays of solid-forms of substances, such as compounds and rapid-screening methods therefor to identify solid-forms, particularly of pharmaceuticals, with enhanced properties. Such properties include improved bioavailability, solubility, stability, delivery, and processing and manufacturing characteristics. The invention relates to a practical and cost-effective method to rapidly screen hundreds to thousands of samples in parallel. The invention further provides methods for determining the conditions and / or ranges of conditions required to produce crystals with desired compositions, particle sizes, habits, or polymorphic forms. In a further aspect, the invention provides high-throughput methods to identify sets of conditions and / or combinations of components compatible with particular solid-forms, for example, conditions and / or components that are compatible with advantageous polymorphs of a particular pharmaceutical.

The invention concerns arrays of solid-forms of substances, such as compounds and rapid-screening methods therefor to identify solid-forms, particularly of pharmaceuticals, with enhanced properties. Such properties include improved bioavailability, solubility, stability, delivery, and processing and manufacturing characteristics. The invention relates to a practical and cost-effective method to rapidly screen hundreds to thousands of samples in parallel. The invention further provides methods for determining the conditions and / or ranges of conditions required to produce crystals with desired compositions, particle sizes, habits, or polymorphic forms. In a further aspect, the invention provides high-throughput methods to identify sets of conditions and / or combinations of components compatible with particular solid-forms, for example, conditions and / or components that are compatible with advantageous polymorphs of a particular pharmaceutical.

The invention discloses a method for enriching and recovering rare earth from phosphorite, which drives a large quantity of rare earth elements to be enriched into a phosphate system and be separated and recovered by inhibiting loss of the rare earth in phosphogypsum through optimizing the technological conditions and adding a calcium sulphate crystal seed and / or an active additive on the premise of not changing the wet-method phosphate process. Compared with the prior art, the method controls proper technological conditions and particularly adds the calcium sulphate crystal seed and / or the active additive, can improve the crystalline morphology of the phosphogypsum, reduce the eutectic effect and the adsorption effect of phosphate rare earth and calcium sulphate, reduce enrichment of the phosphate rare earth and the calcium sulphate to the phosphogypsum, make the enrichment ratio of the rare earth in phosphate reach more than 80 percent, and be favorable for recovering the rare earth from the phosphate. Moreover, the method can meet the requirements of wet-method phosphate production, has simple technique and high content of rare earth in the phosphate, and can adopt proper technology to recover rare earth from the phosphate and realize effective combination of rare earth recovery technology and phosphorization technology.

The present invention relates to the technical field of chemical raw material preparation, and particularly to a method for preparing calcium sulfate dihydrate crystal whisker from phosphorus gypsum. The method comprises the following steps: preparing calcium sulfate dihydrate without impurities, preparing a crystal whisker, washing, and drying to obtain the calcium sulfate dihydrate crystal whisker. By preheating hydrochloric acid and matching the hydrochloric acid with phosphorus gypsum at a certain ratio at a constant temperature, the reaction can proceed and the materials is not wasted, the impurities contained in the phosphorus gypsum can be properly removed maximatily, the impact rate of impurities on the generation of calcium sulfate dihydrate crystal whisker is decreased, the content of calcium sulfate component is increased, the production rate of calcium sulfate dihydrate crystal whisker is improved and the production costs of calcium sulfate dihydrate crystal whisker prepared by comprehensively utilizing phosphorus gypsum are reduced.

Adsorbed gaseous species and elements in a carbon (C) powder and a graphite crucible are reduced by way of a vacuum and an elevated temperature sufficient to cause reduction. A wall and at least one end of an interior of the crucible is lined with C powder purified in the above manner. An Si+C mixture is formed with C powder purified in the above manner and Si powder or granules. The lined crucible is charged with the Si+C mixture. Adsorbed gaseous species and elements are reduced from the Si+C mixture and the crucible by way of a vacuum and an elevated temperature that is sufficient to cause reduction but which does not exceed the melting point of Si. Thereafter, by way of a vacuum and an elevated temperature, the Si+C mixture is caused to react and form polycrystalline SiC.

The invention discloses a 3D nitrogen-doped graphene / molybdenum disulfide compound and a preparation method thereof. A 3D nitrogen-doped graphene / molybdenum disulfide composite material (3D G-N / MoS2) is formed via synthesis under the alkaline condition in a homogeneous precipitation method by taking CaC2O4 as a pore forming agent and using a bifunctional reagent thioacetamide to provide a nitrogen source and a sulfur source. CaC2O4 in laminations is removed by ultrasonic dissolution under the acidic condition to form the 3D porous nitrogen-doped graphene / molybdenum disulfide composite material. The preparation method is simple and environment-friendly, MoS2 nano-sheets are uniformly distributed in the surface of graphene, the contact area with graphene is larger, the catalysis performance is high, and the method can be widely applied in the fields including electrocatalysis, photocatalysis and hydrogen evolution catalysis.

The invention discloses a method for preparing a nanotube doped with titanium dioxide by a two-step presynthesis method. Firstly, a sol-gel method or a hydrolysis method and other methods are adopted to synthesize nano particles doped with the titanium dioxide for target elements; secondly, the nano particles are made into the nanotube doped titanium dioxide by the hydrolysis method. The method has simple and feasible process, wide and application range for the doped elements; moreover, the nanotube prepared by the method has thin tube wall, small tube diameter, large surface area, response to visible light, and wide application prospect in aspects such as photocatalysis, photosensing, photoelectric conversion and so on.

The invention provides a sol-solvent thermal method for synthesizing a nanocrystalline oxide powder. The method comprises the following: (1) a step of preparation of inorganic salt mother liquids, during which the inorganic salt taken as a material is dissolved in an organic liquid medium or water to prepare a mother liquid of the inorganic salt with definite concentration; (2) a step of preparation of a precipitation reactant liquid, during which alkali is dissolved in an organic liquid medium or water, proper quantity of surfactants are added to prepare the precipitation reactant liquid with definite concentration; (3) a step of preparation of sols, during which, at a certain temperature, while stirring, the prepared reactant liquid is slowly added in the prepared mother liquid of the inorganic salt, the reactant liquid and the mother liquid of the inorganic salt are kept reacting for a period of time after adding the reactant liquids in the mother liquid of the inorganic salt, and the transparent sols are obtained; and (4) a step of solvent thermal reaction of the sols, during which the prepared sols are put in a reaction kettle and reacted for a period of time under a certain temperature and pressure, the products obtained are subjected to filtering, washing and drying, and the nanocrystalline oxide powder is obtained.

The invention provides a method for preparing taurine through solid isethionic acid sodium salt. The method includes the following steps that continuous concentration and crystallization are conducted on addition liquid prepared by enabling sodium hydrogen sulfite to react with ethylene oxide, dissolution is conducted through the solid isethionic acid sodium salt obtained in a centrifugal mode, ammonia is fed, sodium taurate is obtained through a high-temperature high-pressure synthetic reaction, finally, sulfuric acid neutralization and extraction are conducted on, solid taurine is obtained, sodium taurate is regenerated by applying mother liquor to the synthetic reaction indiscriminately, and zero emission of taurine mother liquid is achieved. According to the method, concentration and crystallization are conducted on the addition liquid, water-soluble impurities in the addition liquid are removed, and the overall quality of the addition liquid is improved, so that the impurities generated in the synthesis reaction are reduced effectively, the quality, the crystal form and the yield of products can be improved remarkably, meanwhile, indiscriminate application of all of the mother liquor is achieved, and the problem that in a traditional process, the environment is polluted due to the fact that extracted taurine mother liquor cannot be well utilized and is discharged is well solved.

The invention relates to a desulfurization process of flue gas or waste gas by using an external regenerative cycle magnesium sulfate method. The flue gas or the waste gas containing sulfur dioxide is continuously introduced into an absorbing tower, the sulfur dioxide in the flue gas or the waste gas is absorbed by circularly spraying magnesium sulfite absorbing liquid, the magnesium sulfite in the absorbing liquid is transformed into magnesium bisulfite, the sulfur dioxide in the flue gas or the waste gas is removed, the absorbing liquid at the bottom of the absorbing tower is partially or fully shunted to enter in a regeneration system outside the tower and reacts with magnesium oxide slurry for regeneration, the obtained regenerative liquid is filtered, the magnesium sulfite solid is recovered, the filtrate is returned backed to the absorbing tower for cycle absorption and the sulfur dioxide in the flue gas or the waste gas is continuously removed. Due to the adoption of the regeneration process of the absorbing liquid, the pH value of the regeneration reaction end point and the transformation ratio of the agent are increased, the temperature of the absorbing liquid is reduced, the absorbing liquid has the characteristics of high pH value (7.2-8.5), low temperature (38-48 DEG C) and high absorbing capacity and the absorbent activity of the absorbing liquid is effectively improved.

The invention discloses a W-containing high-nickel ternary positive electrode material. The high-nickel ternary positive electrode material comprises spherical morphology secondary particles and monocrystalline morphology particles at the same time, the monocrystalline morphology particles basically do not contain W element, and the spherical morphology secondary particles are doped with W element; the preparation method comprises the following steps: mixing a nickel salt, a cobalt salt and a manganese salt according to a molar ratio, and adding ammonia water and a sodium hydroxide solution for coprecipitation to prepare a precursor A; mixing a nickel salt, a cobalt salt, a manganese salt and a tungsten salt, and preparing a precursor B containing a tungsten element through co-precipitation of ammonia water and a sodium hydroxide solution; and mixing the precursor A, the precursor B, a lithium source and a compound containing a doped element M, and carrying out high-temperature sintering in an aerobic atmosphere to obtain the high-nickel ternary positive electrode material simultaneously containing spherical secondary particles and single-crystal particles. The secondary sphericalparticles in a product can increase the capacity, and meanwhile, a crystal structure cannot generate obvious phase change during lithium ion deintercalation in the cycle process, so that the cycle performance is favorably improved.

The present invention relates to technological process of producing fine aluminum hydroxide powder as fire retardant stuffing, and is especially technological process of producing fine aluminum hydroxide powder with high crystallization degree. The gel seed prepared with sodium aluminate solution through CO2 introducing carbon process and with sodium aluminate solution through aluminum sulfate neutralization process is converted via a special process into fine pure alpha-aluminum hydroxide powder without beta-aluminum hydroxide. The fine pure alpha-aluminum hydroxide powder is coated, modified and stoved to obtain submicron level pure alpha-aluminum hydroxide powder. Or, the completely converted fine powder slurry is added into sodium aluminate solution directly or after being concentrated and further decomposed to obtain fine aluminum hydroxide powder with excellent fire retarding performance.

The invention discloses a method for separating and extracting sterol from wool fat. The method comprises the following step of: (1), carrying out saponification reaction on the wool fat in an alkali-alcohol solution; (2), carrying out saponification double decomposition on calcium chloride and the product obtained in the last step to obtain a calcium soap and wool alcohol; (3), filtering the obtained filtrate in vacuum, extracting under refluxing filter residue by utilizing low-level fatty alcohol, collecting filtrate and adding fatty acid to the filtrate to remove the residual calcium ion; (4), acidifying and bleaching filter cake to obtain the wool acid; and (5), carrying out recrystallization to obtain a refined product. The steps are carried out, so that the purity of obtained cholesterol is higher than 93% and the yield is more than 78%. The method disclosed by the invention has the advantages that the obtained product is high in purity and yield, excellent in color and crystal form and free of peculiar smell, the process flow is simple and easy to operate, and the solvent and the chromatography media in the process flow can be recycled without generating wastes, so that the process cost is low and the industrial production can be realized.

The invention discloses a preparation method for magnesium-aluminium hydrotalcite and the method comprises the following steps: (1) preparing an aluminium chloride aqueous solution with the concentration of 0.24-0.3g / ml, adding magnesium oxide to the aluminium chloride aqueous solution according to the mole ratio of Mg: Al being 2-3:1, heating and stirring at the constant temperature of 40-80 DEG C for 2-4 hours, and obtaining a mixed solution; (2) adjusting the pH value of the mixed solution obtained in step (1) to be 9-10, and keeping on the reaction at 40-80 DEG C for 2-4 hours; (3) crystallizing the seriflux obtained after the reaction in step (2) at a constant temperature of 60-80 DEG C for 12-24 hours; (4) filtering the reaction solution obtained after the crystallization in step (3), washing, drying and grinding to obtain the magnesium-aluminium hydrotalcite. According to the method of the invention, the raw materials used is low cost and easy to get, and the atom conversion rate high, and industrialization cost can be reduced.

The invention relates to a preparation method for a petal-shaped molybdenum disulfide hollow mesoporous carbon sphere by in-situ growth, and belongs to the technical field of nanometer material production. The preparation method comprises the steps of mixing ethanol, deionized water, ammonia water, tetraethyl orthosilicate, resorcinol and formaldehyde for reaction; drying a solid phase and performing calcination in argon; etching the solid phase with a sodium hydroxide solution to obtain the solid phase, and drying the solid phase to obtain the hollow mesoporous carbon nanometer sphere; mixingsodium molybdate dihydrate, thiourea and the hollow mesoporous carbon nanometer sphere for hydrothermal reaction, performing centrifugal washing after hydrothermal reaction, drying the solid phase, and performing high-temperature calcination under protection of argon atmosphere to obtain the petal-shaped molybdenum disulfide hollow mesoporous carbon sphere by in-situ growth. The preparation method has the advantages that the raw material is low in cost, the process is environmental-friendly, high yield is achieved, and the prepared petal-shaped molybdenum disulfide hollow mesoporous carbon sphere by in-situ growth can be used as a lithium ion battery electrode material, a photocatalytic material or an electrocatalytic material.

The invention discloses nano zero-valent iron prepared by using iron and steel acid-cleaning wastewater and a preparation method and application thereof. The preparation method comprises the following steps: filtering acid-cleaning wastewater without removing iron ions in the iron and steel industry; regulating pH value of filtrate; successively adding ethanol solution and polyvinylpyrrolidone; adding sodium borohydride, absolute ethanol and water to prepare into sodium borohydride solution; stirring under protection of inert gas for reaction; and carrying solid-liquid separation, collecting, washing and drying solid to obtain the nano zero-valent iron. In the invention, addition of polyvinylpyrrolidone is equivalent to the mass of total iron ions in a reaction system; and the mole number of sodium borohydride is as at least three times as that of the iron ions in the total reaction system. The method can effectively convert the iron ions in the acid-cleaning wastewater in the iron and steel industry into the nano zero-valent irons, and the conversion rate reaches up to over 99%; sizes of the nano zero-valent iron particles prepared by the method are between 50-80 nm; and the nano zero-valent iron particles are spherical particles, and have good crystal forms and strong capability of degrading polybrominated diphenyl ethers.

The invention discloses a hydrothermal synthesis method for sodium niobate powder, which comprises the following steps: putting niobium pentaoxide and sodium hydroxide in a molar ratio of 0.05-10 into an autoclave, and adding deionized water into the autoclave according to a filling rate between 50 and 90 percent to adjust the concentration of the sodium hydroxide to between 0.1 and 15 mol / L; sealing the autoclave, putting the autoclave into a pit furnace or an oven, raising the temperature to between 120 and 240 DEG C in a temperature rise rate of 1 to 5 DEG C per minute, preserving heat for 4 to 72 hours, and then cooling along with the furnace; and taking out and opening the autoclave, pouring an obtained product into a beaker, repeatedly filtering and washing with deionized water until the washed solution is neutral, putting obtained powder into an oven, and baking at a temperature of between 40 and 100 DEG C for 6 to 24 hours. The method is simple, saves energy, reduces emission, has low cost, and is suitable for mass production; and the prepared sodium niobate powder has high purity, good fluidity, narrow particle size distribution, low degree of particle agglomeration, and perfect crystal growth.

The invention discloses a preparation method of nano iron oxide yellow or nano iron oxide red. The preparation method comprises the following steps: (a) adding a polymerization inhibitor in a ferrite solution with iron ion concentration of 0.05mol / L-1.2mol / L, and dropwise adding a precipitator until the pH value is 3.5-5.0 so as to form a reaction system; (b) continuously reacting for 90-120 minutes to obtain a product after dropwise adding an oxidant in the reaction system; (c) filtering the product obtained from the step (b), washing and drying the obtained filter cake so as to obtain the nano iron oxide yellow; and (d) firing the nano iron oxide yellow obtained from the step (c), cooling the fired nano iron oxide yellow to obtain the nano iron oxide red. By using the method, the particle size of the product can be effectively controlled between 20-100 nanometers, and the nano iron oxide yellow and nano iron oxide red are obtained by subsequent processing; and the method has the characteristics of simple process, small pollution, low energy consumption and short period.

The invention relates to a preparation method of crystal L-arginine alpha-ketoglutarate, comprising the following steps: preparing water solution of L-arginine, and slowly adding alpha-ketoglutaric acid into the water solution, wherein the mol ratio of L-arginine and alpha-ketoglutaric acid is 1:1 or 2:1; reducing pressure and concentrating the alpha-ketoglutaric acid at 50-80 DEG C after complete dissolution, removing water accounting for 20-60 percent of the total volume and cooling to 20-30 DEG C; slowly adding an organic hydrophilic solvent or a mixed solvent of a polar hydrophilic solvent and a non-polar hydrophilic solvent; and carrying out temperature reduction, crystallization, filtering, washing and vacuum drying to obtain the crystal L-arginine alpha-ketoglutarate. Compared with the prior art, the invention has the advantages of reasonable process, simple steps, easy operation, good crystal form of the obtained product, difficult caking, convenient transportation and use, high purity (more than or equal to 98 percent) and high yield (80-86 percent) of the product, and the like, and is suitable for industrialization production.

The invention discloses a preparation method of improved di-lysine-aspirin, comprising the following steps: adding a DL-lysine aqueous solution with the mass percentage concentration being 25-30 percent to an alcobolic solution of aspirin at the temperature of 15-25 DEG C; enabling the mass ratio of DL-lysine to aspirin to be 1:(1.3-1):1.5; mixing and crystallizing for 5-15 minutes; then adding precipitation alcohol with the mass being 3-4 times of aspirin; reducing the temperature within 10 DEG C, and mixing and culturing crystal for 0.5-1.5 hours; filtering and then obtaining crystal; and washing the crystal by an amount of absolute ethyl alcohol for 1-2 times. The invention enables the acid value of a product to be reduced below 6.0 by changing the mixture ratio of reactants, enables the crystal fluidity of the product to be enhanced by changing the flow acceleration of materials and enables the appearance and free oxybenzoic acid of the product to be improved by reducing the temperature of the whole system, thereby reducing the acrimony and the sensitization of medicines and improving the quality of aspirin.

The invention discloses a method of synthesis octahedral manganese molecular sieve by ultrasound, which is that: under the reaction temperature of 40 - 100 DEG C, acidic liquid of potassium permanganate and manganese sulfate are mixed in molar ratio within 0.5 to 1.5, the mixture is sent into an ultrasonic water bath to react for a certain time; the obtained material is filtrated, washed and dried, and the octahedral manganese molecular sieve (OMS-2) is finally made. The produced material can be used for electrode materials, adsorption of heavy metal ion in sewage and catalysis and oxidation of organic compounds such as phenol, methanol, formaldehyde and cyclohexane, low-temperature catalysis and oxidation of CO. In addition, the method is simple and easy to apply and can quickly synthesize OMS-2 material.

The invention belongs to the field of inorganic chemistry, and particularly relates to an efficient zinc phosphate micro-nano anticorrosion agent preparation method, wherein the product is applied in the field of metal heavy corrosion. According to the present invention, a cycle ultrasonic cavitation effect and a high-temperature high-pressure water bath thermal effect are adopted to perform synchronous and synergetic regulation to prepare the efficient zinc phosphate micro-nano anticorrosion agent, wherein the synchronous and synergetic effect of the two effects is adopted so as to make the product system be well dispersed, ensure the uniformity of crystal nucleation and effectively solve the difficult problem of difficult synchronous regulation on the particle size and the crystallization degree of the nanometer crystal, and a microwave heating mode is adopted to dry the product so as to reduce the agglomeration; the prepared micro-nano zinc phosphate product has advantages of high purity, complete crystallinity, narrow particle size distribution, good dispersion and the like, wherein the effective corrosion protection time of the zinc phosphate micro-nano anticorrosion agent is up to 1056 h and is far superior to the effective corrosion protection time of the commercially available zinc phosphate anticorrosion material; and the method has characteristics of simple process and low cost, and is suitable for large-scale production.

The invention discloses an MOF-5 nondestructive modified carbon fiber reinforced resin-based wet friction material and a preparation method thereof. The preparation method comprises the following steps: firstly, treating carbon fibers to remove a surface sizing agent other pollutants, then treating the carbon fibers by nitric acid at a certain temperature to obtain functionalized carbon fibers forproviding active sites for subsequent growth, dissolving the carbon fibers, zinc nitrate hexahydrate and terephthalic acid in an N,N-dimethylformamide solution, carrying out uniform magnetic stirring, then carrying out a hydrothermal reaction to modify the carbon fibers to obtain MOF-5 modified carbon fibers, finally, mixing the modified carbon fibers with aramid fibers, paper fibers and resin toprepare friction material body paper, and carrying out hot-pressing curing process to obtain the MOF-5 modified carbon fiber reinforced resin-based wet friction material. According to the invention,loss caused by a conventional treatment process on carbon fibers can be avoided, and strength of the fibers is not damaged while surface activity of the fibers is improved.

The invention belongs to the field of preparation of inorganic metal compounds, and particularly relates to a method for preparing rutile-type titanium dioxide. The method for preparing rutile-type titanium dioxide comprises the following steps: 1) adding sulfuric acid into titanium slag to obtain an acid hydrolysate; 2) leaching the acid hydrolysate obtained in the step 1) with dilute sulfuric acid; 3) filtering the titanium solution obtained in the step 2), adding ammonia water into the obtained filtrate, and adding a reducer to obtain a titanium solution in which the TiO2 concentration is 100-130 g / L; 4) hydrolyzing the titanium solution obtained in the step 3), and filtering to obtain a titanium dioxide hydrate solid and a hydrolysis mother solution; and 5) calcining the titanium dioxide hydrate obtained in the step 4) to obtain the rutile-type titanium dioxide. The invention provides a clean production method for producing rutile-type titanium dioxide from low-grade titanium slag, and provides an effective way for comprehensively utilizing titanium resources and preparing titanium dioxide (titanium white).

The invention belongs to the field of porous materials, and discloses a hierarchical pore HKUST-1 material, a preparation method and an appliance. The method for preparing the hierarchical pore HKUST-1 material comprises steps: trimesic acids and benzoic acids are dissolved in a mixed solution of three kinds of solvents of water, ethyl alcohol and dimethyl formamide (DMF), are uniformly stirred and mixed, and then are added with Cu(NO3)2.3H2O to uniformly stir and mix, thereby obtaining a mixed solution. The mixed solution is put into a stainless steel high pressure reaction kettle, has a hydro-thermal synthesis reaction in 100-120 DEG C, and reaction products are separated, washed and dried to obtain the hierarchical pore HKUST-1 material. The hierarchical pore HKUST-1 material uses benzoic acids as structure-directing agents, does not need other auxiliary reagents, has rich microporous, mesoporous and macroporous, and has excellent application prospect in bulky molecular catalysis, adsorption and separation and the like.

The invention discloses a preparation method of calcium phosphate nanopowder with a controllable length-to-diameter ratio and calcium-to-phosphorus ratio. The method comprises the step: carrying out areaction by mixing phosphate or phosphoric acid with a calcium salt to prepare the calcium phosphate nanopowder, wherein the one-dimensional size of a calcium phosphate nanoparticle can be regulatedto be 50nm-5mu m and the length-to-diameter ratio can be regulated to be 2-50 by adding a pH regulator into a reactant, components and proportions of the calcium phosphate nanopowder serving as a product can be regulated by controlling the feeding ratio of the phosphate or phosphoric acid to the calcium salt to be 1.5-1.67, and the calcium phosphate nanopowder is beta-tricalcium phosphate and / or hydroxyapatite. According to the method disclosed by the invention, the length-to-diameter ratio of the product is regulated by controlling the proportion of weak bases and relatively strong bases in the pH regulator; the calcium-to-phosphorus ratio of the product is controlled by changing the feeding ratio of a calcium source to a phosphorus source; a supergravity technology is combined to enhancea micromixing effect, so that the calcium phosphate nanopowder is prepared; and the preparation method is low in production cost, simple in operation, good in repeatability, better in application performance and wider in application range.

A preparing method of hexagonal piece barium ferrite nanometer magnetic powder includes: the predecessor body composed with the mixture of powdered BaCO3 and FeO(OH) powder the fineness of which belongs to nanometer is burnt for hexagonal piece barium ferrite nanometer magnetic powder. The optimal fineness of powered BaCO3 is nanometer and optimal nanometer FeO(OH) powder is the spindly FeO(OH) powder. The invention is suitable for application of perpendicular magnetic recording medium of high density and microwave absorber. The invention has the outstanding advantages as follows: well energy conservation effect for low calcinations heat and short calcinations time; high purity and good crystal model; simple process, low level demand for production facility, that is suitable for mass production in industry.

The invention discloses a method for preparing metal nickel nano wires, which comprises the following steps: firstly, dissolving a metal nickel salt and polyvinylpyrrolidone into ethylene glycol according to the mass ratio of 1:0.5-1:20; secondly, adding hydrazine hydrate and 5-15 ml ethanol according to the fact that the mol ratio of the hydrazine hydrate to the metal nickel salt is 0.3-1.9:1; and thirdly, performing heating reaction for 3 to 48 hours until black deposit is generated in a solution, washing and drying the black deposit, and obtaining the black powder metal nickel nano wires, wherein the metal nickel salt is any one of nickel acetate, nickel sulfate, nickel chlorite and nickel nitrate, and the molar concentration of the metal nickel salt in the ethylene glycol is between 0.001 and 0.1 mol / L. The prepared metal nickel nano wires are continuous and compact and have good crystal formation and higher slenderness ratio.

The invention provides a method for prolonging the service life of a CdS nano photocatalyst. The method is characterized by depositing a layer of 1-10 A as protective layer (TiO2, ZnO, Al2O3, AZO, and the like) on the surface of a CdS nano particle synthesized hydrothermally by virtue of an atomic layer deposition technique. On the premise of guaranteeing relatively a high catalytic efficiency, light corrosion occurrence is effectively reduced, and therefore the service life CdS nano photocatalyst is prolonged from 1 hour to over 18 hour. The preparation method effectively reduces the harm to the light CdS nano particle and prolongs the catalyst life of the CdS nano particle.

The invention relates to a preparation method of a carbon-coated tungsten sulfide hollow nanosphere with a shell layer with a sandwich structure, and belongs to the technical field of production of anano material. The preparation method comprises the steps of: mixing alcohol, deionized water, ammonium hydroxide, ethyl orthosilicate, resorcinol and formaldehyde to perform a reaction, obtaining a solid phase to dry, and after calcining in argon, etching by aqueous solution of sodium hydroxide to obtain a hollow mesoporous carbon nanosphere; and after dissolving tungsten chloride and thiourea solid in the deionized water, adding the hollow mesoporous carbon nanosphere, after carrying out ultrasonic dispersion, performing a hydrothermal reaction, and after obtaining a solid phase to dry, calcining in the argon so as to obtain the carbon-coated tungsten sulfide hollow nanosphere of which the shell layer has the sandwich structure. The preparation method disclosed by the invention has the characteristics of cheap process raw material, simple and environmental-friendly process, high yield and excellent performance; the prepared carbon-coated tungsten sulfide hollow nanosphere of which the shell layer has the sandwich structure can be applied as a lithium ion battery electrode material, a photocatalysis material or an electro-catalysis material.