101results about How to "Controllable particle size distribution" patented technology

The invention relates to a preparation method of spherical metal powder. The preparation method comprises the steps of heating a metal bar to melt in a heating device, so as to obtain melted liquid, and breaking the melted liquid into small droplets by using plasma as droplet breakage power, so that the small droplets are cooled and solidified and are collected so as to obtain the spherical metal powder. According to the spherical metal powder prepared by adopting the preparation method, almost no satellite particle exists, the oxygen content is less than 1200 ppm, and the occupancy of the powder below 53 mum reaches 90% according to weight percent; the spherical metal powder has the advantages of high degree of sphericity, narrow particle size distribution, low impurity content, good flowability, low oxygen content, no satellite particle, simple process, reliable technique, easiness in control over product particle size, high production efficiency and low inert gas consumption and is suitable for mass production, and the particle size distribution satisfies the 3D printing requirements.

The invention discloses a wild antheraea pernyi silk fibroin microsphere and a preparation method of the microsphere. The preparation method comprises the steps of degumming and dissolving tussah silk; subjecting the above processed tussah silk to dialysis treatment to obtain a solution of the wild antheraea pernyi silk fibroin; adjusting the concentration of the solution to 10-100mg / ml; adding in a citric acid solution or an acetic acid buffer solution at the temperature of 10-60 DEG C to adjust the pH value to 3-6; subjecting the resulting solution to ultrasonic oscillation and stirring treatment to obtain a suspension of the wild antheraea pernyi silk fibroin microsphere; centrifugalizing, freezing and drying the suspension to obtain the biodegradable wild antheraea pernyi silk fibroin microsphere, the diameter of which is 0.1-10mu m. The preparation method of the invention prepares the wild antheraea pernyi silk fibroin microsphere by means of in-situ self-assembly generation and is simple in process procedures; the prepared microsphere is uniform in size distribution, keeps the RGD sequence of the wild antheraea pernyi silk fibroin, promotes the cell recognition of the microsphere, improves the targeting property and bioavailability of drugs, can function as a carrier with bioactive substance to carry an enzyme drug, a nucleic acid drug, a polypeptide drug, a protein drug and the like, and can be applied to diagnosing and treating diseases and the like.

The invention discloses high-strength hollow glass beads, comprising the chemical components: 71-76.5% of SiO2, 1.5-2% of Al2O3, 4.5-5% of B2O3, 2.5-3% of Li2O, 0.2-0.5% of SO3, 5.5-6% of Na2O, 2.3-3.5% of BaO, 4.5-6% of CaO4 and 2.5-3% of P2O5, wherein the density is 0.4-0.8g / cm<3>, the compressive strength is 30-130MPa, the particle size is smaller than or equal to 80mum, the floatage rate is greater than or equal to 90%, and the softening temperature is greater than or equal to 700 DEG C. The preparation method comprises the following steps: preparing BaO-Al2O3-SiO2-Li2O-SO3-CaO-P2O5-Na2O-B2O3 gel by adopting a sol-gel method for hydrolyzing a polyhydric alcohol salt; preparing silica nano powder by using an alkoxide hydrolysis-precipitation method; quickly dewatering and drying to synthesize spherical precursor powder after stirring, mixing and homogenizing in an atomization manner; carrying out vitrification sintering. The high-strength hollow glass beads are applicable to high-temperature and high-pressure fields with special requirements, such as underwater solid buoyancy materials and deep well cementing cement in oil drilling.

The invention relates to a chemical mechanical polishing abrasive particle CeO2 and a method for preparing the same, belonging to the rare earth powder material chemical preparation technical field. The invention is to prepare the CMP abrasive particle by utilization of cerous inorganic salt solution and homogeneous precipitation agent. The method comprises the following steps that: the cerous inorganic salt and the precipitation agent are prepared into solution with certain proportion; the solution is uniformly mixed through ultrasonic vibration; deposits are generated after the solution is heated to a certain temperature; serum is kept stand, aged, filtered and calcined, and then the CeO2 abrasive particle is prepared. The method also accelerates the nucleation rate through addition of surface active agent so as to reduce the reaction temperature, and simultaneously the nodulizing degree of the abrasive particle obtained is also good. The method prepares the CMP abrasive particle, wherein, the CMP abrasive particle belongs to the single-phase cubic crystal system; the space group is O<5>H-FM3M; the dispersibility is good; the grain fineness distribution is uniform; the shape is similar to a sphere; and the specific surface area BET is more than 0 and less than 50m<2> / g.

A preparation method of high-quality gamma-TiAl spherical powder comprises the following steps that (1) a gamma-TiAl alloy bar is smelted according to ingredient compounding of a gamma-TiAl base alloy; (2) the smelted gamma-TiAl alloy bar is subjected to forging so as to remove internal defects, and stress relief annealing is performed; (3) annealed gamma-TiAl alloy bar is subjected to finish turning processing to obtain a high-precision alloy bar; (4) the gamma-TiAl alloy bar is loaded to a reaction chamber, and the reaction chamber is vacuumized and filled with inert gas; (5) the end part of the high-precision alloy bar is heated by PREP powder making equipment, atomized drops are thrown away from the end part of the alloy bar, the drops are cooled rapidly into spherical particles in the inert gas environment, and the spherical particles fall into a collector; (6) prepared gamma-TiAl alloy powder is screened and packaged in the inert gas protection environment; (7) the gamma-TiAl alloy powder prepared with the method has the advantages that the degree of sphericity is high, the oxygen increase is low, no mixing exists, and the particle distribution is controllable.

The invention discloses a method to prepare high-temperature high-surface area aluminum oxide and aluminous compound oxide. It uses surface-active agent, assistant surface-active agent, non-water soluble organic solvent, water, inorganic salt and basic material as raw materials to manufacture two reversed-phase microemulsions, then mixing the two microemulsions to react and produce sol, and then filtering, drying, baking, etc, to obtain high-thermal stability aluminum oxide and aluminous compound oxide. When they are baked at 1000 deg.C for 10h, their specific surface area are both kept at 50 sq m / g above, for an example, when the modified aluminum oxide is baked at 1100 deg.C for 10h, its specific surface area is 185.2 sq m / g. Their particle sizes are uniformly distributed and can be controlled. The raw materials are cheap and easy to obtain.

A process for preparing the cobalt oxide used for the positive electrode of Li ion battery includes such steps as reaction of cobalt chloride (or nitrate) solution on ammonium bicarbonate solution to obtain cobalt carbonate, calcining at 500-1000 deg.C to obtani Co3O4, pulverizing and classifying.

The invention relates to a method for preparing thermosetting amino resin microspheres. The invention aims to provide the method which can prepare amino resin microspheres with wide range of grain size and higher water resistance. The technical scheme I adopted by the invention is that the method for preparing the thermosetting amino resin microspheres comprises the following steps of: (A), adding an amino compound and an aldehyde compound into an aqueous solution of silica sol with an alkaline catalyst to obtain a prepolymer of water soluble amino resin, wherein the weight ratio of the amino compound to the aqueous solution of silica sol is 100: 0.5-100; (B), adding an acidic curing agent into the prepolymer of the water soluble amino resin to obtain amino resin microspheres; and (C), aging the microspheres, filtering, drying and grinding the microspheres to obtain a finished product. The amino compound may be one or more of tripolycyanamide, urea, thiourea, cyanuric acid and phenylated tripolycyanamide, and the aldehyde compound may be one or more of formaldehyde, paraformaldehyde, acetaldehyde, benzaldehyde and furfuraldehyde.

The invention discloses a preparation method and application of cross-linked hyaluronic acid gel microspheres. The preparation method comprises the steps that a hyaluronic acid alkaline solution withthe concentration being 5-30% g / ml is prepared, inorganic dispersants are added into organic phase cyclohexane under stirring, full stirring is conducted, and thus the inorganic dispersants are uniformly dispersed. By adopting the technical scheme, the preparation method is simple, products are controllable in particle size, intact in form, low in impurity content, high in purity and highly transparent, and meanwhile, the degradation period can also be controlled within the range of 30-300 days. In the preparation method and the application of the cross-linked hyaluronic acid gel microspheres,the cross-linked hyaluronic acid gel microspheres prepared through the preparation method can be used for producing medical or prevention products and used for injection, tissue repair and tissue strength in animals and especially in humans; and because of the extremely-low impurity content, the products have good biocompatibility and degradability, and clinical safety is ensured.

The invention discloses a preparation method for an asphalt hard carbon negative electrode material for a lithium ion battery, wherein the preparation method comprises the following steps: 1) making commercial sulfonated asphalt and deionized water into an asphalt solution, and filtering out undissolved asphalt particles, to obtain a clarified water-soluble asphalt solution; 2) adding a graphite micro-powder to the asphalt solution obtained in the step 1); 3) carrying out spray granulation of the graphite asphalt solution obtained in the step 2), to obtain asphalt hard carbon microspheres with the particle size of 1-51[mu]m; and 4) heating the asphalt hard carbon microspheres obtained in the step 3) up, and drying to obtain the asphalt hard carbon negative electrode material for the lithium ion battery. The used raw materials are cheap in price and wide in sources; no any organic solvent requires to be added in the whole production process; the asphalt hard carbon particle size distribution can be controlled; the preparation process easily realizes industrialized production. The prepared asphalt hard carbon negative electrode material has excellent lithium intercalation and removal capacities, and is suitable for power lithium ion batteries.