72results about How to "Narrow particle distribution" patented technology

A catalyst for the polymerization or copdymerization of olefin is composed of Ti-contained solid component A, organoaluminium compound B and organosilicon compound C. Said A is prepared through dissolving magnesium halide in the mixture of organic epoxy compound, organophosphorus compound and inertial diluent, adding educing agent and magnesium halide or its derivatives to educe out Mg/Ti contained deposit, and carrying a surface modifier, a titanium halide or derivative and an electronic doner. It can be used for the polymerization of propene or copolymerization of propene-ethene.

A catalyst for polymerization or copolymerization of ethylene is prepared through dissolving magnesium halide in organic epoxy compound, organic phosphorus compound or inertial diluent, adding alkane educing aid, porous inertial carrier and halide of Ti, and educing. It is possible to add alcohol compound and/or electron donor. Its advantages are high activity and copolymerizing performance, and high sensitivity to hydrogen regulation.

This invention provides a catalyst for ethylene polymerization or copolymerization and its synthesis. The catalyst comprises magnesium halide/inorganic matter composite carrier prepared by spray drying. This invention also provides the method for preparing the magnesium halide/inorganic matter composite carrier and the method for synthesizing the catalyst by using the composite carrier. The obtained catalyst has such advantages as high catalytic activity, no breakage of catalyst particles, and narrow particle size distribution. The polymer has such advantages as good particle morphology, little fine powder and high packing density.

The invention discloses a three-dimensional micro-nano material composed of nano CoFe2O4 and a preparation method thereof. The three-dimensional micro-nano material is of a double-hexagon flower dumbbell type opposite-connected structure and is obtained by the following steps: 1) adding tervalent iron salt and divalent cobalt salt in polyol, stirring to obtain transparent liquid, heating for reacting, and then cooling to room temperature and collecting precipitates; 2) centrifugally washing the precipitates with ethanol, and drying so as to obtain a yellow green cobalt ferrite precursor; and 3) firing the precursor so as to obtain the CoFe2O4 micro-nano structure with the double-hexagon flower dumbbell type opposite-connected structure. According to the invention, the process is simple and practicable, the distribution range of the obtain material particle is narrow, and the micro-nano material has the advantages of single dispersibility, single product phase and good reaction repeatability; and the synthesized material simultaneously has characteristics and advantages of a micro-nano structure and a nano structure.

A dry toner contains fine particles having average sphericity of 0.93 to 0.99, a content of the fine particles having a particle diameter of 2 μm or less in the dry toner is 20% by number or less. A method for manufacturing a dry toner includes a process for dispersing in an aqueous medium containing water and a water-soluble organic solvent, a toner composition contained in an organic solvent by using fine solid dispersing agent; and a process for contracting volume of the dispersed toner composition. Further, the image forming apparatus having a photoconductor; a charger for charging the photoconductor; a light irradiator for irradiating the electrophotographic photoconductor to form a latent electrostatic image; a developer for developing the latent electrostatic image to form a developed image; and a transfer for transferring the developed image to a recording material, and the developer contains the dry toner abovementioned.

The invention relates to penniform large-grain cerium-based composite oxide powder with high specific surface area and a preparation method thereof. The preparation method comprises the following steps of: dripping a mixed solution of cerium-based salt and non-cerium-based salt (one or more of nitrates or sulfates of samarium, gadolinium, neodymium, yttrium, zirconium, lanthanum, barium, calcium and strontium) to a precipitant solution at 30-60 DEG C under stirring; keeping the pH of a reaction solution at 8-12, wherein the mole ratio of metal ions to a precipitant is 1: (2-6); carrying out aging reaction on the reaction solution at 60-80 DEG C for 6-20 hours to obtain precipitates; filtering and washing till filter liquor is neutral; drying the precipitates at 60-120 DEG C for 6-20 hours, and then calcining at 400-1100 DEG C for 4-20 hours to prepare the penniform large-grain cerium-based composite oxide powder. The products are grains which have good dispersity and uniform size; the grains are irregularly connected together through a large quantity of nano-plates and form penniform shapes; the average grain diameter of the grains is 1-20 micrometers; the specific surface area of the grains is 70-90 m<2>/g; and the thicknesses of the nano-plates are 20-100 nanometers.

The invention relates to a kind of ethylene polymerization or co-polymerization method. The method contains the steps as follows: in ring-canal form reactor and condition of catalyst, procee polymerization reaction with ethylene and more than a C3-C8 alpha-alkene slurry, and the catalyst mentioned above contains the reaction product of titanium catalyst constituent and organic aluminium compound. Ethylene and alpha-alkene combined polymer manufactured by the method has low density, and needs little quantity of comonomer. So it can make the residual comonomer in polymer quantity decline badly, which already had flash vaporization and renovation with diluent in ring-canal polymerization reaction industrial art, and can improve the quality of end combined polymer. At the same time, the polymer also has high bulk density, and low fine powder content in resin.

The invention discloses a preparation method of a sapphire polishing solution. The preparation method is characterized by comprising the following steps: (1) uniformly dispersing alpha-Al2O3 nano-crystals which have average particle size in the range of 100-300nm and are taken as crystal seeds in an aluminum salt water solution as a precursor solution; (2) preparing the precursor solution into spherical powder containing the crystal seeds of the alpha-Al2O3 nano-crystals as a precursor by virtue of a spray drying process; (3) sintering the precursor by controlling the temperature range within 900-1200 DEG C to obtain alpha-Al2O3 powder; (4) dispersing the alpha-Al2O3 powder into water, and adjusting the pH value and size of secondary particles to obtain the sapphire polishing solution. According to the preparation method disclosed by the invention, the obtained sapphire polishing solution has the advantages of small average particle size, narrow particle size distribution, good water dispersibility, wide and adjustable range of process parameters and capability of greatly improving the efficiency and the precision of sapphire polishing.

The invention relates to a method for smashing glutinous rice, in particular to application of the smashing-screening coupling technology in the water-grinding glutinous rice flour production technology. The method for producing water-grinding glutinous rice flour comprises the steps that ash and impurities in rice are removed through a pretreatment process; coarse grinding is conducted on the soaked glutinous rice through a grinder and primary screening is conducted by a vibrating screen classifier; glutinous rice husks in glutinous rice milk are removed and 50-80-mesh milk is obtained; refined grinding is conducted through an ultra-fine grinder, secondary screening is conducted through the vibrating screen classifier, and ground glutinous rice milk particles are all over 100 meshes; the glutinous rice milk is dehydrated and dried and the finished product is obtained. The screening process is adopted for twice through the grinding technology and the method has the advantages that the technology is simple, cost is low, the prepared water-grinding glutinous rice flour is high in purity, low in impurity contents of fat, ash and the like, small in number of spots, high in whiteness and fineness and long in expiration date the mean grain size is in narrow distribution, the energy consumption is low, the production capacity is large and the like.

An Fe/Mn catalyst for Fischer-Tropsch synthesis is prepared from Fe, Mn, Ni, alkali-earth metal, alkali metal and carrier proportionally through continuous coposition and spray drying. Its advantages are large specific surface area, high transform rate and high selectivity to hydrocarbon.

The invention discloses a method for extracting and separating shikimic acid from fructus anisi stellati. The method particularly comprises the following steps of 1 pretreatment, wherein an extract obtained by extracting the fructus anisi stellati is added to pure water with the weight equal to that of the extract, the materials are put into a high-speed dispersing and emulsifying machine to be treated, and a high-speed dispersed and emulsified mixture is obtained; 2 column chromatography, wherein the high-speed dispersed and emulsified mixture obtained in the first step passes through an anion resin column to enable the shikimic acid to be exchanged and adsorbed, elution is conducted with a sodium hydroxide solution, and eluent is obtained; 3 desalination, wherein the eluent obtained in the second step passes through a cationic resin column for desalination, and sodium salt is removed; 4 crystallization, wherein the desalinated eluent is concentrated and then added into acetone to enable the shikimic acid to be precipitated and crystallized, and then recrystallization is conducted with acetone.

The invention discloses a hollowed wampee sauce and a preparation method thereof. The method comprises the following steps: 1) selecting a raw material and treating; 2) performing high-speed dispersion emulsifying treatment: crushing hollowed wampee fruit obtained from step 1) with a beater, then adding pure water of the same weight, putting in a high-speed dispersion emulsifier to give a high-speed dispersion emulsion; 3) performing pressurized extraction: putting the emulsion treated in step 2) in a high pressure tank, pressurizing to 4kg/cm<2>, so that the pressure is uniform, and maintaining for 10-15min, then restoring to normal pressure in 1-3s, and obtaining a pulp extract mixture; 4) pickling: adding salt into the pulp extract mixture obtained from step 3) to be sealed in a container 3-4 months, 5) adding ingredients for pickling: taking out the pickled material obtained from step 4), adding the ingredients and mixing well, then adding to the sealed container to be pickled for 1-2 months; 6) subpackaging and sterilizing to obtain a finished product.

The invention discloses a preparation method of a water-in-oil type nanometer emulsion. The preparation method comprises the following steps: preparing and generating a water-in-oil type emulsion by utilizing T-type and Y-type furcated combination channels; in a dispersion phase containing an oil or water component, diluting the water-in-oil type emulsion through adding a nonionic polymer surfactant, simultaneously stirring for more than 5 minutes at a certain stirring speed and dropwise adding a certain volume of water at the same stirring speed; controlling the temperature of the water-in-oil type emulsion to be 5-60 DEG C under the action of stirring and keeping the temperature for 3-6 minutes; adding a solution containing an aqueous solution and a hydrophilic surfactant component in the water-in-oil type emulsion, wherein the volume ratio of an oil phase to a water phase is not less than 7:3, and the ratio of the total mass of the surfactant to the mass of the water phase is 0.3-1.0; then enabling the temperature of the whole system to reach a room temperature under stirring so as to prepare the stable water-in-oil type nanometer emulsion. A low-energy emulsification method coupling the component and the temperature overcomes the defect of limited applicability of a conventional low-energy emulsification method and has the advantages of being wider in applicability, low in energy consumption and low in cost.

The invention provides a preparing process of double-perovskite Y2MnCoO6 dielectric ceramic, relates to a ceramic preparing process and aims at solving the defects existing in the traditional preparing process of Y2MnCoO6 dielectric ceramic that the process is heavy and complicated, the finished product is poor in condition and the like. The invention provides a sol-gel method, comprising the steps of: mixing and dissolving ingredients, adding corresponding catalyst or complexing agent, drying, pyrolyzing, grinding, prefiring, and firing to prepare Y2MnCoO6 dielectric ceramic. The obtained Y2MnCoO6 dielectric ceramic can be widely applied to the field of ceramic things.

The invention discloses a high-activity carbon-supported platinum catalyst for low-platinum-loading proton exchange membrane fuel cell and a preparation method thereof. The method comprises the following steps: (1) purifying carbon powder; (2) preparing carbon ink, namely mixing carbon powder, isopropanol, deionized water and zirconium oxide balls, and performing ball milling to obtain the carbonink; (3) preparing an ultrathin carbon powder layer, namely dripping carbon ink into a flat-bottom vessel filled with deionized water, uniformly spreading the carbon particles on the water surface, and performing drying to form the ultrathin carbon powder layer; and (4) preparing the high-activity carbon-supported platinum catalyst, namely preparing the high-activity carbon-supported platinum catalyst by taking the ultrathin carbon powder layer as a substrate and sputtering platinum through magnetron sputtering. The Pt average particle size of the prepared high-activity carbon-supported platinum catalyst is 3 nm, distribution is uniform, the particle size range is 2.5-3.5 nm, and the size distribution range is narrow. The carbon-supported platinum catalyst can be applied to a cathode catalyst layer of a proton exchange membrane fuel cell, and compared with commercial Pt/C, the power density of the cell is greatly improved.

The invention provides a process and a device for preparing nano-powder by utilizing ultrasonic static electricity. The process and the device combine the advantages of ultrasonic atomization and static atomization and skillfully overcome the disadvantages of the two. The process mainly comprises the following steps that: raw material is heated to be in a liquid state through a heating furnace, degassed through a degassing device and then conveyed to an atomizer through a pipeline; the raw material in the atomizer is first precharged via a precharging device and then is guided into a nozzle of a piezoelectric-type ultrasonic atomization system through a flow-guiding pipe in order to be atomized; the obtained material is accelerated through a primary acceleration-ring group, enters an inductive charging ring, and is charged and atomized again; the atomized raw material is accelerated through a secondary acceleration-ring group, joined and mixed through a Y-shaped pipe; mixed compounded fog drops are irradiated with an alpha ray source to remove surface charge; the charge-removed fog drops pass through a flow-guiding device (a resistance-wire heating pipe is arranged in the flow-guiding device to perform corresponding thermal decomposition on the fog drops needing thermal decomposition), enter a condenser, are condensed into solid powder; and the solid power leaves the atomizer and then enters a collection device in order to be collected. Therefore, the nano-powder with product stability, high performance, narrow particle distribution, uniform particle distribution, good monodispersity, little agglomeration, high purity and good sphericity can be prepared by utilizing equipment which is simple, low in cost, free from pollution, easy to control and suitable for large-scale continuous industrial production.