99results about How to "Small particle size distribution range" patented technology

The invention relates to a surface-modified nano silicon dioxide and a preparation method thereof, particularly a method for preparing lipophilic nano silicon dioxide by in-situ modification by a sol-gel process, belonging to the field of functional nano materials. The invention adopts a sol-gel process to prepare the nano silicon dioxide under the common catalytic action of acid and alkali, and performs in-situ modification on the nano silicon dioxide by using a silane coupling agent, so that the nano silicon dioxide becomes lipophilic instead of hydrophilic. The wetting property and dispersity of the modified nano silicon dioxide in the polymer are improved.

The invention discloses a nanometer metal powder continuous producing device, comprising a vacuum measuring aerating system, a plasma/sensitive heating evaporating powder preparing system, a particle controlling system, a nanometer metal powder cyclone grading collecting system, a nanometer powder catching collecting system, a gas cooling circulating system, a water cooling circulating system, an electric controlling detecting system, a metal nanometer powder inactivating system and a powder vacuum packing storing system. The invention has high vacuum and three-gun structure, uses plasma constant-weight packing storing device, and plasma/electromagnetic sensitive evaporation or the like to realize continuous production of nanometer metal powder, change gas component and flux or the like.

The invention relates to a method for preparing a load type high-dispersion multi-component precious metal nanoparticle catalyst. The method comprises the steps of 1) under inert atmosphere, uniformly stirring a solvent and a surface active agent, then adding a precious metal precursor solution, rising the temperature, reacting for a certain period of time, cooling to the room temperature, adding normal hexane, and performing extraction layering; 2) uniformly mixing the obtained upper layer nanoparticle solution with a carrier, and stirring or performing ultrasonic treatment; and 3) centrifugating, washing and drying or baking the mixed solution to obtain the catalyst. For the precious metal catalyst, even under a relatively high carrying amount, relatively good precious metal nanoparticle dispersion degree can be still guaranteed; the particle sizes of the particles are uniformly distributed; the precious metal carrying amount is controlled easily and accurately; the particle sizes and the components of multi-component particles can be controlled; and the catalysis application range is wide. The process is simple; the preparation cost is low; the applicability is high; and load-type high-dispersion precious metal and the multi-component precious metal nanoparticle catalyst can be prepared in a large scale.

The invention relates to a method for preparing a high-dispersion precious metal and alloy nanoparticles thereof, which comprises: 1) uniformly stirring glycol and specific surfactant in a certain proportion in an inert atmosphere to prepare milky emulsion; 2) adding solution of precursor of the precious metal into the mixed solution, heating the resulting solution to a given temperature, keeping the temperature for a certain time period with stirring, cooling to room temperature, adding nonpolar solution and extracting; and 3) performing the rotary evaporation of upper solution to remove solvent, washing with ethanol or mixed solution of ethanol and normal hexane, centrifuging and obtaining the high-dispersion precious metal and the alloy nanoparticles thereof. The nanoparticles prepared by the method have uniform particle size and high monodispersity, and can be separated easily; the alloy is controllable in particle size and composition; the process is simple; the preparation cost is low; the solvent system is cheap; and the method is widely applicable and can realize large-scale preparation easily.

The invention discloses a pharmaceutical composition, in particular a pharmaceutical composition prepared by adopting a prescription medicine originated from a traditional Chinese medicine pill and an ultrafine grinding technology, and a preparation method thereof. The preparation method induces an auxiliary material ultrafine grinding technology, thereby enabling mineral medicines to have smaller granularity and greatly increased specific areas, ensuring that medicinal materials from animals and plants have over 90 percent of cell shell-broken rate after being ground in an ultrafine way, active ingredients in the cells can be better exposed to be in a release condition, and the dissolution rate and the bioavailability of the active ingredients are greatly enhanced, maintaining the compound grinding homogenization and fully embodying the traditional Chinese medicine features. The preparation has the advantages that the dissolution rate of the active ingredients is high, the dissolution time is short, the absorption and the utilization are full, the curative effect is good, the production cycle is short, the production cost is low, and the like, thereby having wide market prospect and further satisfying and guaranteeing the requirements of people on medicines.

The invention discloses a redox-sensitive core-crosslinked Pulullan nano particle having dual-targeting property and a preparation method thereof, preparation of a drug carrying nano particle with the compound as a carrier, and in-vitro releasing researching of the drug carrying nano particle. The method includes the steps of: 1) performing esterification reaction to lipoic acid and Pulullan to convert the water-soluble Pulullan into a hydrophobic polymer, which is beneficial to preparation of nano particles and entrapment of a hydrophobic medicine; 2) conjugating the polymer with folic acid to form a folic acid-Pulullan-lipoic acid conjugate, and performing crosslinking to inner cores of the nano particles in DTT in catalytic quantity to prepare stable and reversible folic acid-Pulullan-lipoic acid (FA-Pull-LA) nano particles having dual-targeting property. The drug carrying nano particle is prepared with paclitaxel as a model medicine in a dialysis manner, wherein stability and reduction sensitivity of the drug carrying nano particle are inspected through an in-vitro releasing test. A result proves that the dialysis method for preparing the FA-Pull-LA nano particles is simple and has good repeatability, is easy to achieve expanded production and has high drug carrying rate. The nano particle is stable in vitro and can quickly release the drug in an intracellular reductive environment.

Disclosed is a self-ignited preparation method of spherical nanometer Yttrium europium silicate fluorescent powder, which comprises using tetraethoxysilane, ethanol, deionized water, nitric acid, yttrium oxide, europium oxide, glycine as raw material to prepare transparent glue, evaporating water content in the gel at 500-700 deg C, calcining 2-3 hours at 1100-1500 deg. C, thus obtaining polycrystalline nano sub-micron yttrium-europium silicate fluorescent powder.

The present invention discloses a high-purity activated heavy calcium carbonate. The preparation steps comprise: carrying out mechanical crushing on calcite, and conveying into a grinder to grind to obtain calcium carbonate coarse powder; adding water to the grinded coarse powder, conveying into the grinder, and grinding by using a wet grinding process to obtain a calcium carbonate semi-finished product, wherein a mass ratio of the grinded coarse powder to the water is 2:1-1.5; adding a stearic acid and calcium stearate mixture as a modifying agent to the calcium carbonate semi-finished product, carrying out a modifying treatment, and carrying out a drying treatment; and finally conveying the modified calcium carbonate into a strong magnetic stripe powder screening box to screen to obtain the finished product high-purity activated heavy calcium carbonate. According to the present invention, the physical grinding is used to obtain the heavy calcium carbonate, the heavy calcium carbonate prepared by using the wet grinding has characteristics of high dispersity and small particle size distribution, the performance is excellent especially after the second wet grinding, and the calcium carbonate powder screened through the strong magnetic stripe powder screening box has characteristics of high purity and white chrominance.

The invention discloses Mo2FeB2-based thermal spraying alloy powder which can be used for improving the performance of components and parts and prolonging the service life of the components and parts. The Mo2FeB2-based thermal spraying alloy powder is prepared from the following raw materials in percentage by weight: 14.64-36.5% of FeB, 21.3-47.5% of Mo, 1.3-4.7% of Ni, 2.4-8.1% of Cr, 0-5% of W and 8.82%-49.66% of carbonyl iron. The invention also discloses a preparation method of the Mo2FeB2-based thermal spraying alloy powder. The thermal spraying alloy powder prepared by the method has high purity, narrow distribution range of powder size, high spheroidization rate and good flowability and is suitable for a thermal spraying technology of a wear resistance anti-corrosion coating.

The invention relates to a purification method of acetyl pullulan polysaccharide folate conjugate and a preparation method of nanometer particles thereof. Folate, acetyl pullulan polysaccharide solution, 4-dimethylaminopyridine (DMAP) and a carbodiimide dehydrating agent are mixed for reaction for 5 to 7 days at the temperature of 25 to 28 DEG C, excessive absolute ethyl alcohol is dropwise added into filter liquor for sedimentation, and centrifugation is carried out, the sediment is collected, is dialyzed for 24 to 48 hours by sodium carbonate buffer solution and is dialyzed for 24 to 48 hours in deionized water, and a material is obtained through freezing-drying or vacuum drying. The material is dissolved in dimethyl sulfoxide (DMSO) or other organic solvents, and a dialysis method is adopted for preparing the nanometer particles. The invention has less steps, simple operation and good repeatability and dose not need other stabilizing agents and emulsifiers, and the nanometer particles are in ball shapes, have uniform grain sizes, low absolute potential, and good stability, and do not have significant toxicity for single mainline to mice.

The invention relates to a low-expansion-rate nano-level water absorption microsphere and a preparation method thereof. The prepration method comprises the following steps: preparing a water-phase mixed liquid: uniformly mixing acrylamide, acrylic acid, a cationic monomer, a crosslinking agent and water, and then adding an alkaline substance, thus obtaining the water-phase mixed liquid; preparingan oil-phase mixed liquid: uniformly mixing an oil solvent, a hydrophobic monomer and an emulsifier, thus obtaining an oil-phase mixed liquid; performing polymerization: homogenizing the oil-phase mixed liquid, then feeding nitrogen to remove oxygen, adding an initiator to initiate the polymerization, and controlling temperature of a system to not exceed 70 DEG C through refrigeration equipment; performing post-treatment: after the polymerization reaction is ended, adding nonylphenol polyoxyethylene ether into the reacted mixed liquid, thus obtaining the low-expansion-rate nano-level water absorption microsphere. The microsphere obtained by the method is small in particle size distribution range, low in expansion rate within 30 to 100 nm; the expansion is started within 1 to 2 hours; the low-expansion-rate nano-level water absorption microsphere is particularly applicable to blocking of a special compact bottom layer block.

The invention relates to nano sensitized materials for an organochlorine pesticide, which is characterized in that titanium salts and nickel salts which are used as raw materials undergo steps of dissolution, deposition, aging, filtering, washing, drying, grinding and calcining, etc., forming Tio2 nano powder dressed by Nio, wherein the ratio between Ti atoms and Ni atoms, the grain size of which is less than 50nm, is 100:15 to 25. A sensor of the organochlorine pesticide made of sensitized materials of the invention has the advantages of good selectivity and flexibility and being capable of detecting the content of the organochlorine pesticide in different agricultural products.

The invention relates to the technical field of microcapsules and discloses semen myristicae essential oil microcapsules as well as a preparation method and application thereof. The semen myristicae essential oil microcapsules provided by the invention comprise starch octenyl succinate, inulin and semen myristicae essential oil. The semen myristicae essential oil microcapsules are prepared by selecting the unconventional inulin as one of wall materials and matching with the starch octenyl succinate, so that the microcapsules have good thermal stability and relatively high encapsulation efficiency and essential oil retention ratio; furthermore, a specific boiling drying-process technology is matched so that the flowability of a product can be further improved; the product has a smaller grain diameter and a centralized grain diameter distribution range; the utilization rate of the product is improved.

The invention relates to a method for freezing and vacuum-drying micro-nanopowder slurry. The method for freezing and vacuum-drying the micro-nanopowder slurry comprises the steps of primary cooling, wherein the slurry is placed in a cavity and is cooled; secondary cooling, wherein the cavity is vacuumized to enable the slurry to be cooled again; low temperature and constant temperature maintaining, wherein the slurry is maintained at a low temperature; primary warming, wherein the slurry is warmed stage by stage; secondary warming, wherein the slurry is warmed stage by stage again; high temperature and constant temperature maintaining, wherein the slurry is maintained at a high temperature; material taking, wherein micro-nanopowder is taken out of the cavity. According to the method for freezing and vacuum-drying the micro-nanopowder slurry, the phenomenon of agglomeration of dried micro-nanopowder can be avoided, and compared with a learning method, the particle size distribution range of the dried powder is narrowed.

The invention belongs to the field of antioxygen, in particular to an emulsion antioxygen and a preparation method thereof. The emulsion antioxygen is emulsified and compounded by the following raw material reagents at the proportion: main antioxygen, auxiliary antioxygen, emulsifying agent, dispersing agent and defoaming agent. The emulsion antioxygen has better oxidation resistance than other similar antioxygens and can achieve the optimal oxidation resistance effect, and the total solid content of the emulsion antioxygen is more than 52%. The emulsion antioxygen has the advantages of good oxidation resistance effect, big activity, low volatility, high durability, no pollution and the like and is especially suitable for protecting tint and pollution-free color polymer thereof. The emulsion antioxygen can be favorably dispersed in ABS (Acrylonitrile Butadiene StyreneAcrylonitrile Butadiene Styre) rubber latex, is ideal antioxygen used preparing ABS by emulsion polymerization and has excellent dispersibility. According to the emulsion antioxygen, the heating oxygen aging time of the ABS resin can be prolonged in the ABS production, the oxidation inducing temperature of the ABS resin is improved, the phenomenon that the ABS resin becomes yellows in the production and processing process thereof can be prevented, the strength of a product can be improved, and the oxidation resistance problem for preparing ABS by emulsion polymerization can be solved.

The invention provides a supersonic jet milling system, which relates to the technical field of powder material milling. A main body comprises an air compressor, an air storage tank, an air freeze dryer, a supersonic jet mill, a cyclone separator, a dust remover and a draught fan, wherein the right end of the air compressor is connected with the air storage tank; the right end of the air storage tank is connected with the air freeze dryer; the right end of the air freeze dryer is connected with the supersonic jet mill; the right end of the supersonic jet mill is connected with the cyclone separator; the right end of the cyclone separator is connected with the dust remover; and the right end of the dust remover is connected with the draught fan. The supersonic jet milling system is reasonable in structural design, has the advantages of low noise and no vibration and is suitable for a dry type ultrafine milling process; since the impact velocity is high, particles 1-10 micrometers in size are very easy to obtain, and coarse particles in a product can be continuously and circularly milled, so the product with uniform particles and a small particle size distribution range can be obtained.

The invention discloses a polydithiothreitol based drug-loading nano system and a preparation method and application thereof. A disulfide-bond-containing novel polymer namely polydithiothreitol controllable in composition and structure is prepared, and a nano carrier for targeted delivery of antitumor drugs is successfully created. Different antitumor drugs are grafted to hydroxide radicals of polydithiothreitol to form nanoparticle solution with particle size uniformity and stability through a nanoparticle preparation process such as a single-emulsion method and a nano precipitation method. The novel polymer namely polydithiothreitol is stable in property after drug grafting and high in biocompatibility and degradability and has GSH fast reduction responsiveness, targeted delivery efficiency of the nano carrier is improved, positioning controlled release of drugs in tumor cells is realized, bioavailability of hydrophobic drugs is improved, and a promising application prospect and a wide development space in the field of medicines are realized.

A table-type airflow crushing device for laboratories relates to the technical field of powder material crushing. A main body of the table-type airflow crushing device comprises an air compressor, an air storage tank, a precise filter, an air freezing dryer, a degerming filter, a fluidized bed airflow crusher, a cyclone separator, a deduster and a draught fan which are sequentially connected in closed mode through pipelines, and the fluidized bed airflow crusher, the cyclone separator and the deduster are fixed on the same worktable. The table-type airflow crushing device for laboratories is reasonable in structural design, has the advantages of being low in noise and free of vibration, is widely applied to ultrafine crushing of dry powder materials of medicines, chemical engineering, metallurgy and the like to prepare samples in the laboratories, can obtain products with uniform particles and small particle size distribution range, is good in sealing performance and free of dust, and does not cause unnecessary sample loss.

The invention relates to a paint for pattern-printed tableware and an implementation method thereof. The paint comprises the following components in percentage by mass: 10-35% of siloxane, 5-20% of filler, 1-10% of pigment, 1-5% of non-adhesive assistant, 1-5% of catalyst and the balance of water-soluble silica sol. The paint is simple to use, and has the advantages of low cost and favorable decorative effect; and the pattern can be customized to satisfy the market demands.

The invention discloses a high-sphericity stainless steel powder for additive manufacturing, and a preparation method thereof. The preparation method comprises the preparation steps of screening, spheroidizing, cleaning and drying. The preparation method provided by the invention is simple, high in production efficiency, high in finished product quality, suitable for mass production, and capable of meeting the demand of additive manufacturing; and meanwhile, the prepared stainless steel powder is excellent in performance, compact in powder structure, and stable in performance, so that the stainless steel powder for additive manufacturing can be applied to a worse working condition.