39results about How to "Uniform crystal size" patented technology

The present invention describes methods for preparing high quality nanoparticles, i.e., metal oxide based nanoparticles of uniform size and monodispersity. The nanoparticles advantageously comprise organic alkyl chain capping groups and are stable in air and in nonpolar solvents. The methods of the invention provide a simple and reproducible procedure for forming transition metal oxide nanocrystals, with yields over 80%. The highly crystalline and monodisperse nanocrystals are obtained directly without further size selection; particle size can be easily and fractionally increased by the methods. The resulting nanoparticles can exhibit magnetic and/or optical properties. These properties result from the methods used to prepare them. Also advantageously, the nanoparticles of this invention are well suited for use in a variety of industrial applications, including cosmetic and pharmaceutical formulations and compositions.

The invention belongs to the technical field of graphene material synthesis and preparation and more particularly relates to a preparation method of a wafer level graphene micro-nano monocrystal array. The method comprises the steps of performing chemical vapor deposition on the surface of polycrystal copper foil in a mixed atmosphere containing methane and oxygen for growth to form the graphene micro-nano monocrystal array, wherein methane serves as a carbon source for graphene growth; the copper foil serves as a catalytical substrate for the graphene growth; and the oxygen serves as etchinggas in a formation process of the graphene monocrystal array. According to the method, a graphene array structure is directly prepared by a simple one-step chemical vapor deposition method; the disadvantage of complicated steps of complicated micro-nano machining, etching and the like required by a graphene film in a subsequent application is overcome; quick and low-cost preparation of a large area micro-nano graphene monocrystal is achieved; and the application in large-scale device preparation is facilitated.

The embodiments described herein include one embodiment that provides a method for controlling sugar crystallization. The method includes, during a crystallization process, determining supersaturation of a sugar slurry of syrup and regulating influx of syrup into the sugar slurry to promote sugar crystallization in a closed-loop manner based upon the determined supersaturation.

The invention relates to a preparation method of an anti-wear tungsten carbide alloy material, and belongs to the technical field of metal metallurgy. The preparation method comprises the following steps of firstly, taking expanded graphite as a template, mixing the expanded graphite with an ammonium tungstate solution and starch, heating and evaporating to crystallize and separate out tungsten inthe form of ammonium paratungstate, and controlling uniform crystal granularity by virtue of polyhydroxy steric hindrance of the starch so as to enable thermally reduced tungsten to be uniformly attached to the surface of the expanded graphite; then generating a tungsten carbide layer on the surface of the expanded graphite, and therefore, obtaining tungsten carbide powder with a graphite interlayer structure; and finally, blending and sintering the tungsten carbide powder and other metal powder, and preparing the wear-resistant tungsten carbide alloy material finally. Due to the fact that the tungsten carbide interlayer structure can slide along the metal powder interlayer and directionally move in the friction direction in the friction state, therefore, consumption of internal energy ofhard alloy material is reduced, abrasion of the hard alloy material is reduced, damage to a hard alloy structure due to repeated volume change can be avoided through the interlayer structure, and theabrasion resistance is further improved.

The invention relates to the technical field of pharmaceutical preparations, and particularly discloses a preparation method of a tedizolid phosphate freeze-dried preparation for injection. The preparation method of the tedizolid phosphate freeze-dried preparation for injection comprises the following steps: a, adding tedizolid phosphate and a freeze-drying protective additive into water for injection to obtain tedizolid phosphate liquid medicine; b, sequentially cooling the liquid medicine to -8 to -10 DEG C and -40 to -50 DEG C, and keeping for a specific time; heating the liquid medicine to -15 DEG C to -10 DEG C, and cooling the liquid medicine to -40 DEG C to -50 DEG C, and keeping the temperature for a certain period to obtain a freeze-dried product; c, under the vacuum condition, heating the freeze-dried product to -30 to -10 DEG C and 40 to 50 DEG C, and keeping the temperature for a certain period, so as to obtain the tedizolid phosphate freeze-dried preparation for injection. The preparation method is simple to operate, the time cost for preparing the tedizolid phosphate freeze-dried preparation for injection is remarkably reduced, and the high-quality tedizolid phosphate freeze-dried preparation for injection, which is low in impurity and moisture content, can be obtained.

The invention discloses an oxytetracycline hydrochloride preparation method which comprises the following steps: 1, adding oxytetracycline and calcium chloride into methanol, uniformly stirring, and filtering to obtain filtrate, wherein oxytetracycline hydrochloride comprise the following raw materials: 1500-2100 L of methanol, 350-500 Kg of oxytetracycline and 35-50 Kg of calcium chloride; 2, controlling the temperature of the filtrate to 20-26 DEG C, adding a hydrochloric acid-methanol solution to obtain a mixed solution, and performing intermittent stirring on the mixed solution to separateout oxytetracycline hydrochloride, wherein the hydrochloric acid-methanol solution contains 26 Kg of hydrogen chloride; and 3, performing centrifugal separation on the mixed solution after the oxytetracycline hydrochloride is separated out, and drying, thereby obtaining the oxytetracycline hydrochloride. The oxytetracycline hydrochloride preparation method disclosed by the invention has the advantages that the mass yield of the oxytetracycline hydrochloride is stabilized at 96% or higher, and the content of impurities such as dehydrated mycin, alpha-apo-oxytetracycline, and beta-apo-oxytetracycline in the product is low.

The disclosure relates to a thin film forming device and a thin film forming method using the same capable of improving the film quality of a silicon thin film by dividing a reaction space in a process chamber of the thin film forming device and thereby forming the silicon thin film on a substrate in a first space and treating a surface of the silicon thin film, formed in the first space, in a second space by using plasma. By the thin film forming device and the thin film forming method using the same according to the disclosure, with a trend that a pattern is complicated and the depth of the pattern increases, impurities in a thin film may be more efficiently removed, a uniform thin film may be formed on a pattern, and the grain size of the crystals of a silicon thin film may be made uniform.

The invention discloses a cobalt-nickel bi-metal hydroxyl phosphite rod-like crystal array film and a preparation method of the cobalt-nickel bi-metal hydroxyl phosphite rod-like crystal array film. The preparation method comprises the following steps: dissolving nickel nitrate hexahydrate, cobalt nitrate hexahydrate and sodium hypophosphite in deionized water, and adding N, N-dimethylacetamide; soaking the pre-cleaned activated carbon fibers into the prepared solution, and carrying out sealed reaction in a reaction kettle at 140-160 DEG C for 10-20 hours; and after the reaction kettle is naturally cooled to normal temperature, taking out the activated carbon fiber, repeatedly cleaning with absolute ethyl alcohol and deionized water, and drying at 60 DEG C for 8 hours to obtain a compact and uniform M11 (HPO3) 8 (OH) 6 (M = Ni + Co) rod-like crystal array film on the surface of the activated carbon fiber. The rod-like crystal array film obtained by the invention is simple and safe in preparation method, and the array crystal is uniform and compact, has stable and uniform surface performance, and can be applied to the fields of novel energy storage, catalysis and sensing.

The invention relates to the technical field of photocatalytic materials, and particularly discloses a preparation method of Bi4NbO8Cl. The preparation method of the Bi4NbO8Cl comprises the followingsteps: carrying out a hydrothermal reaction on bismuth nitrate pentahydrate and potassium chloride under alkaline conditions, and calcining a hydrothermal reaction product, niobium pentoxide, potassium chloride and sodium chloride to obtain the Bi4NbO8Cl. The preparation method of Bi4NbO8Cl disclosed by the invention is simple to operate, low in preparation cost and low in energy consumption, andthe obtained Bi4NbO8Cl is good in crystal form structure and relatively high in photocatalytic activity.

The invention discloses a method for synthesizing a Nu-6(1) molecular sieve. The method comprises the following steps that 1, a mother solution is prepared, wherein a template agent and ethyl alcohol are mixed to obtain a solution A, a silicon source, an alkali source and water are mixed to obtain a solution B, an aluminum source, water and acid with a pH value regulating effect are mixed to obtain a solution C, the solution B is dropwise added into the solution A, the solution C is dropwise added into the mixed solution of the solution A and the solution B, aging is conducted, and seed crystals are added to obtain the mother solution; 2, the mother solution obtained in the step 1 is dried and ground into powder; 3, the powder and water are mixed, and the Nu-6(1) molecular sieve is synthesized through crystallization. According to the technical scheme, the content of the water and the template agent in the raw materials is greatly decreased, so that raw material cost and environmental pollution are greatly reduced, and the green chemistry requirement is met.