15 results about "Particle-size distribution" patented technology

The invention provides a copolymerized nylon powder material used for selective laser sintering, and a preparation method thereof. The method comprises the following steps: carrying out a copolymerization reaction on a short-chain nylon raw material and a long-carbon chain nylon raw material by using a copolymerization reaction principle to obtain copolymerized nylon resin, carrying out cryogenic crushing, drying and screening on the copolymerized nylon resin, and adding a flow aid and an antioxidant to obtain the copolymerized nylon powder material used for selective laser sintering. The preparation method has the advantages of simple process and easiness in control, and copolymerized nylon powder particles have a narrow particle size distribution, can be well used in secondary molding, and is suitable for being used in the field of manufacturing of additional materials.

The invention discloses an acetic acid styracin nanometer capsule and a preparation method thereof. The acetic acid styracin nanometer capsule is prepared from gelatin/gum arabic as a wall material, acetic acid styracin as a core material, tween 20 as an emulsifying agent, and glutamine aminopherase as a curing agent by using a composite coacervation method, and in the process of the preparation, the quantity of the gelatin, the gum arabic, the acetic acid styracin, the tween 20 and the glutamine aminopherase are computed in a mass ratio of 1:1:1-2:1-2:0.25. The acetic acid styracin nanometer capsule has favorable storage stability and heat stability, and can durably and effectively control the release of the core material, wherein the average particle diameter is 168.48nm-211.67nm, and the particle size distribution coefficient is 0.132-0.154. The acetic acid styracin nanometer capsule can be used in the fields of spice, essence, foods, cosmetics, detergents, and the like.

The invention discloses a method for preparing silicon nitride powder with saw dust, comprising the steps of: taking saw dust and silica sol as raw materials; sufficiently using the characteristics such as the porosity, the easy impregnating and the high-temperature carbonizing of the saw dust, and the easy grinding of the produced saw dust; drawing inorganic substance into the saw dust by means of sol-gel; filling the gel which takes silicon dioxide as main component into gaps of woods, so that the raw materials are evenly mixed; carbonizing, carbon thermally reducing and nitriding silica sol-impregnated saw dust in a high-temperature controllable atmosphere furnace to prepare Si3N4 ceramics powder. The method is characterized of obtaining the Si3N4 ceramics powder with higher purity, high alpha phase content and small grain diameter, and marrow granularity distribution range; preparing the high-quality Si3N4 ceramics powder with a technology with lower cost; reasonably and sufficiently utilizing the saw dust; and recycling waste material. The method is experimentally tested to have good performance for synthesizing the silicon nitride powder, and be an effective and feasible way.

The invention relates to a method of preparing artificial rutile with a ferric salt solution leaching method and belongs to the technical field of chemical metallurgy. The method of preparing high-grade artificial rutile by taking sand titanium concentrates as a raw material is simple in process and equipment, convenient to operate and low in production cost and overcomes the defects of higher energy consumption and difficulty in treating waste liquid. The method comprises the following steps: titanium concentrate strong reduction, ferric salt solution leaching, solid-liquid separation, solid substance washing and drying and filtrate purification. The method of preparing the artificial rutile with the ferric salt solution leaching method enables titanium oxides to form a more stable porous solid solution structure by controlling atmosphere and adopting high-temperature strong reduction, accelerates the leaching reaction speed of iron and prevents titanium-containing particles from pulverizing at the same time; and the obtained artificial rutile as a product is better in particle size distribution and proper in particle size and is an ideal raw material for producing titanium tetrachloride by fluidizing chlorination.

The invention relates to a composite microsphere with a radial fibrous mesoporous shell layer/hollow nuclear layer structure and a preparation method of the composite microsphere. The composite microsphere is provided with a cavity, a nuclear layer and a mesoporous shell layer, wherein the mesoporous shell layer is provided with radial fibrous mesoporous channels. The composite microsphere is highin sphericity and surface regularity, uniform in particle size distribution and high in monodispersity and strength. The preparation method of the composite microsphere is simple and feasible and facilitates industrialization; preparation of the radial fibrous mesoporous shell layer and removal of an organic template can be completed by means of a one-step method. The composite microsphere has the advantages of high light scattering efficiency, large specific surface area, low density, high porosity and the like, can be widely applied in light diffusion materials and used as a light diffusionagent for heavy haze and can also be adopted in the fields of fillers of coatings, cosmetics, catalysts and water treatment.

The invention provides an efficient preparation method of ultra-precision cutting abrasive sand. The method comprises the following steps: roughly crushing iron-aluminum type garnet crude ore; sequentially processing by scrubbing and sieving through a rotary screen, washing with water through a screw sand washer, and overflowing to deslime; carrying out gravity concentration through a spiral chute to obtain fine-graded garnet with purity reaching 60 to 70%; washing with water again through the screw sand washer; drying to obtain dried and fine-graded garnet sand with water content less than 0.2%; removing dust through a cyclone separator; magnetically separating; removing dust again to obtain fine garnet sand with purity more than 97%; then screening by grades through an ultrasonic sound sieve to obtain cutting garnet sand, wherein the particle size distribution of the cutting garnet sand is that the cutting garnet sand with particle size ranging from 0.045 to 0.053mm is less than 8% in content, and the cutting garnet sand with particle size ranging from 0.053 to 0.1mm is more than 92% in content. The method is simple and high in operability, and the prepared garnet-based cutting abrasive sand is uniform in particle size, high in mobility, and high in cleanness.

The invention discloses a preparation method of nano-magnesium hydroxide. The preparation method comprises the following steps: carrying out ultrasonic dispersion on ammonia water and a sodium hydroxide solution so as to obtain a mixed alkali solution, and adding the mixed alkali solution into a reactor; putting the reactor in an ultrasonic field, dropwise adding a polyethylene glycol 6000 water solution into the reactor in a constant speed, and further carrying out ultrasonic dispersion for 0.5-1 hour; dropwise adding a magnesium chloride water solution into the reactor in a constant speed; after the dropwise adding of the magnesium chloride water solution, further carrying out ultrasonic dispersion for 0.5 hour; adding turbid liquid obtained in the reaction into a hydrothermal reaction kettle for treatment, so as to obtain Mg(OH)2 precipitates; and carrying out suction filtration, washing, drying and grinding on the precipitates, so as to obtain nano-Mg(OH)2. Nano-magnesium hydroxide is prepared by virtue of an ultrasonic-hydrothermal coupling method, and reaction conditions are easily controlled, so that the problems that nano-Mg(OH)2 particles easily form colloid in a solution and are unlikely to be filtered are solved; and the particle size of the prepared nano-Mg(OH)2 particles is small, the particle size distribution is uniform, the crystallization degree is high, the technical flow of the preparation method is simplified, the energy consumption is reduced, and the production cost is saved.

The invention discloses a device and a method for improving particle size distribution of byproduct crystalline salt of chemical strong brine, which are used for circularly heating, crystallizing, separating, drying and the like the chemical strong brine by arranging a circulating heater, a multi-effect evaporation system, a cyclone, a centrifugal machine, a drying bed and the like so as to obtainthe byproduct crystalline salt. By means of the device and method, the proportion of large-particle-size salt in the byproduct industrial salt can be increased, the proportion of powder salt is remarkably reduced by 20-30%, and particle size distribution is more uniform.

The present invention makes it possible to ascertain the particle size distribution of inserted material each time material has been inserted. The particle size distribution monitoring device according to the present invention comprises an information acquisition device for, at least once each time material has been inserted, acquiring information for identifying the particle size distribution of the inserted material and an information processing device for processing the information. The information processing device comprises a particle size distribution identification unit for identifying a particle size distribution each time material has been inserted on the basis of the information acquired by the information acquisition unit at least once each time material has been inserted and a particle size distribution display unit for visualizing the particle size distributions that have been identified by the particle size distribution identification unit each time material has been inserted, associating the visualized particle size distributions for each time material has been inserted with each time material has been inserted, and displaying the same on a screen.

The invention provides a divided type dental polymeric core build-up material including a first paste (A) and a second paste (B), in which each of the pastes is a paste obtained by mixing at least a (meth)acrylate monomer, a filler having a particle size distribution within a range of 0.1 through 40 μm and an average particle diameter of 0.7 through 10 μm, and a fine particle filler having an average particle diameter of primary particles of 0.001 through 0.050 μm, and having a viscosity at 25° C. of 280 through 470 P, and in which one of the pastes includes an oxidant and the other includes a reductant and at least one of the pastes includes a photopolymerization catalyst. The divided type dental polymeric core build-up material of this invention has high operability in core build-up and forms a polymerically cured substance with a good mechanical property.

The present invention provides a zirconium oxide powder, a method for producing.the same, and a material for thermal spraying. The material for thermal spraying comprises a zirconium oxide powder comprising polyhedral particles each having not less than 6 faces, wherein the zirconium oxide powder has D50 of not less than 5 μm and less than 15 μm and a D90/D10 of less than 3. D10, D50 and D90 correspond to the point where the cumulative mass from the small-particle-diameter side reaches 10%, 50%, and 90% in the cumulative particle size distribution.

The invention discloses a hydrophilic hollow silicon sphere as well as a preparation method and application thereof. The hydrophilic hollow silicon sphere is prepared by modifying the surface of a silicon-oxygen structured double-bond silicon sphere, which is formed by performing catalytic reaction on vinyltriethoxysilane and is used as a core, with glutathione, and etching a sphere center with hydrofluoric acid. Drug encapsulation and in-vitro simulated releasing experimental results show that compared with a hollow silicon sphere of a contrast group, the hollow silicon sphere prepared with the preparation method disclosed by the invention has a significant difference in drug loading and in-vitro releasing of camptothecin, so that the hydrophilic hollow silicon sphere prepared with the preparation method is relatively high in loading capacity and relatively good in controlled release effect. The hydrophilic hollow silicon sphere is simple in design; no reaction conditions such as high temperature and high pressure are needed; the particle size distribution of the silicon sphere is uniform; feasibility is provided for industrial production of the hydrophilic hollow silicon sphere; a new way is provided for researches on drug slow release carriers; the hydrophilic hollow silicon sphere has good social and economical benefits.

The invention provides an electrode, a secondary battery, a battery pack, and a vehicle. The electrode is provided with a current collector and an active material-containing layer that is formed on the current collector and contains active material particles. The active material particles include first active material particles including a core particle including a monoclinic niobium-titanium composite oxide and a carbon material layer covering at least a part of a surface of the core particle, and second active material particles including a monoclinic niobium-titanium composite oxide. A particle size distribution diagram obtained by a laser diffraction scattering method for active material particles has a first region corresponding to a particle diameter of a size less than a median particle diameter d50 and a second region corresponding to a particle diameter of a size greater than or equal to the median particle diameter d50. The first particle group contained in the first region contains first active material particles, and the second particle group contained in the second region contains second active material particles. The carbon coating rate of the first particle group ishigher than the carbon coating rate of the second particle group.