16results about How to "Good sphericity" patented technology

The invention belongs to the technical field of ceramic tube preparation, and particularly relates to a pressureless sintered silicon carbide grinding medium and a preparation method thereof. The invention relates to a preparation method of a pressureless sintered silicon carbide grinding medium, which comprises the following specific steps: proportioning: preparing basic materials of the silicon carbide grinding medium according to the weight ratio: 98-99 wt% of submicron silicon carbide and 1-2 wt% of boron carbide; ball-milling and mixing; performing spray granulation; intensely stirring, mixing and granulating; drying the biscuit; dewaxing the biscuit; and sintering at high temperature to finish preparation. The preparation method is simple in technological process, use of large forming equipment such as a dry press and a cold isostatic press is avoided, the production input cost is greatly reduced, and the prepared pressureless sintered silicon carbide grinding medium is good in sphere sphericity degree, high in density, high in strength, high in toughness, ultrahigh in wear resistance, long in service life, resistant to high temperature and good in chemical stability.

This invention relates to the field of refractory materials technology, and more particularly to a cementless magnesia castable and its application method. The castable consists of aggregate, matrix material, and a water-reducing agent; the aggregate is 60-80 parts of magnesia particles; the matrix material is: fine magnesia powder, active α-Al₂O₃ micro powder, sintered corundum powder, silica micro powder, and aluminum-based metal microcapsules. The application method of the cementless magnesia castable is as follows: the water-reducing agent and matrix material are mixed evenly to obtain a premixed matrix material; the aggregate and premixed matrix material are stirred evenly, water is added and wet-mixed to obtain a slurry; the evenly mixed slurry is poured into a mold, vibrated to form the slurry, and then cured. This cementless magnesia castable exhibits certain initial strength, excellent high-temperature performance, excellent resistance to slag erosion and thermal shock, and a long service life, making it widely applicable in tundishes and ladles.

This invention relates to the field of nanomaterials technology, specifically to a method for preparing silica using continuous flow. The method involves mixing an organic base, a surfactant, and water to obtain solution A; mixing a silicon source and an organic solvent to obtain solution B; reacting solutions A and B through a continuous flow apparatus, separating the solid product, and calcining it to obtain silica; wherein the flow rates of solutions A and B are 5-10 mL / min, and the reaction temperature is 20-45℃. In this method, silica is prepared using a continuous flow process, and the prepared silica has a nanosphere morphology with a specific surface area of ​​200-800 m². 2 / g, with a pore size distribution of 2-50 nm and a particle size distribution deviation (PDI) of less than 2%.

This invention provides a method for preparing iron-based amorphous powder, the iron-based amorphous powder, and its applications. The preparation method includes: weighing iron, silicon, ferroboron master alloy, carbon, erbium, and chromium in a predetermined proportion and adding them to a melting furnace to obtain a molten liquid; holding the molten liquid at a constant temperature and allowing it to stand to obtain an amorphous powder liquid; and subjecting the amorphous powder liquid to water-air combined atomization to obtain spherical amorphous powder. This invention solves the problem in the prior art where the amorphous powder has an irregular shape and sharp edges, which easily leads to the accumulation of losses and affects the performance and stability of the magnetic core.

The invention relates to the technical field of inorganic non-metallic materials, in particular to a method for producing electric melting zirconium oxide solid spheres by using a titration method. The method comprises the following steps: uniformly mixing zirconium oxide powder and a stabilizer to form a mixed raw material; and preparing a consumable electrode by adopting the mixed raw material, then melting the end part of the consumable electrode into zirconium oxide melt, and dripping to form the electric melting zirconium oxide solid ball. The method comprises the following steps: melting the end part of a consumable electrode to form a zirconium oxide solution, gathering the zirconium oxide solution into liquid drops with a certain size under the action of surface tension, and naturally dropping from the tail end of the electrode under the action of gravity to prepare the electric melting zirconium oxide solid sphere. The preparation method is short in technological process, and the prepared product is good in sphericity degree, high in density and uniform in chemical component.

The invention belongs to the technical field of drug crystallization, and provides metformin hydrochloride and fenofibrate double-drug-loading particles and a preparation method thereof.The preparation method comprises the following steps that polysaccharide, a solvent I and metformin hydrochloride are mixed and heated, and a homogeneous solution is obtained; mixing the homogeneous solution, fenofibrate and triglyceride to obtain a suspension; a cross-linking agent, a solvent II and the suspension are mixed and placed in a crystallizer to be subjected to a crystallization reaction, and a crystallization solution is obtained; and carrying out solid-liquid separation on the crystallization liquid, washing, and drying to obtain the double-drug-loading particles. The obtained particles are in a solid state and have good stability compared with a micelle drug loading system, meanwhile, the operation unit is simplified by adopting an in-situ crystallization means in the carrier, operation such as mixing, grinding and spray drying is not needed, needed equipment is simple, operation is easy and convenient, and good technical economy and high application value are achieved.

The present application relates to the technical field of preparation of tritium breeder, in particular to a method for batch preparation of Li2TiO3 tritium breeding microspheres and rich phase structure by centrifugal granulation, comprising the following steps: S1, Li2TiO3 ceramic powder is pretreated by spray granulation, then sprayed with a solution of xanthan gum for granulation, and sieved to obtain a green body; S2, the green body is added into a centrifugal granulator, and a second binder solution is sprayed at the same time, so that Li2TiO3 microsphere seeds with a preset diameter are generated by centrifugal granulation; S3, then the second binder solution is sprayed while lithium-containing ceramic powder is added for granulation and bonding; S4, the process of S3 is repeated until ceramic microsphere green bodies with the required diameter are obtained; S5, then deionized water is sprayed in the granulator and continues to roll for 3-8 min; S6, the ceramic microspheres obtained in S5 are dried at constant temperature and humidity, degummed, and sintered. The method can realize batch preparation of high-lithium-content tritium breeding microspheres with single-phase structure or multi-phase structure.

The invention discloses a preparation method of antioxidant nano-copper particles based on an intermediate metastable state, which comprises the following two steps: firstly, reacting copper salt with a first reducing agent and a pH regulator for 10-40 minutes in a first organic solvent of 70-130 DEG C to obtain copper-based intermediate particles of 20-25 nm; and then dispersing the intermediate in deionized water, adding a second reducing agent, a pH regulator and a coating agent, reacting at 70-130 DEG C for 20-60 minutes, so that the coating agent and copper atoms are deposited and synchronously bonded in situ under an alkaline condition to form a continuous coating layer with the thickness of 4-10nm, and finally obtaining the antioxidant nano-copper particles with the particle size of 30-40nm and high sphericity through epitaxial growth control. According to the preparation method, nucleation and growth processes are accurately regulated and controlled under mild conditions, and the nano-copper particles which are uniform in particle size, high in sphericity degree and long-acting in oxidation resistance are directly prepared.

The invention discloses an imrecoxib solid preparation and a preparation method thereof, and belongs to the technical field of pharmaceutical preparations, the solid preparation comprises the following components by mass: 15-25% of imrecoxib, 10-40% of pea maltodextrin, 10-40% of Soluplus, 1-3% of poloxamer, 10-30% of a filler, 10-20% of a disintegrating agent, 0.8-1.2% of a flow aid and 0.8-1.2% of a lubricant. Through synergistic interaction of triple carriers, Soluplus inhibits drug crystallization by means of hydrogen bonds and promotes dispersion; the poloxamer reduces the surface tension and improves the dispersity and the dissolution rate; the pea maltodextrin plays an anti-oxidation role, improves the sphericity, fluidity and stability of the particles, and is low in cost. Aiming at the difficulties that imrecoxib is low in solubility, easy to oxidize and the like, medicine dissolution is remarkably improved, related substances are more stable, and both process robustness and cost control are considered.

This invention belongs to the field of lithium manganese iron phosphate cathode material preparation, and relates to a method for preparing spherical high-density lithium manganese iron phosphate cathode material. This invention utilizes the acid solubility of phosphoric acid to spherically modify the surface of the lithium manganese iron phosphate precursor. The phosphate ester and phosphate diester bonds contained in phosphoric acid can form phosphorus-rich soluble substances with iron, manganese, and other metal elements in the precursor under heating conditions. These substances can dissolve the metal ions on the precursor surface under water bath heating, and then the metal ions are redeposited onto the precursor surface by water bath cooling. Through repeated water bath heating, cooling, and stirring, the crystal planes of the precursor are dissolved and regrown, ultimately forming a spherical precursor.

This invention provides an MC-type carbide-reinforced Nb-based alloy spherical powder, its preparation method, and its application, belonging to the field of metal material preparation technology. The invention involves distributing the MC-type carbide-reinforced Nb-based alloy spherical powder according to its composition, followed by suspension induction melting and casting to obtain a master alloy ingot. The master alloy ingot is then machined to obtain an Nb-based alloy electrode rod. Using the Nb-based alloy electrode rod as raw material, powder is produced by plasma rotating electrode atomization to obtain the MC-type carbide-reinforced Nb-based alloy spherical powder. The MC-type carbide-reinforced Nb-based alloy spherical powder prepared by the method of this invention has uniform composition, controllable particle size with a narrow distribution range, good sphericity, low O and N content, and high purity, making it suitable for additive manufacturing.

This invention discloses a method for preparing high-density, large-particle-size spherical alumina powder, belonging to the field of inorganic non-metallic material preparation technology. The method uses industrial aluminum hydroxide or industrial alumina containing a transition phase as raw material. It involves introducing 1-10% α-alumina seed crystals and 1.0-3.0% composite mineralizer (containing boron and fluorine sources) by mass of the raw materials. After mechanical mixing, the mixture is calcined in air at 1350-1550℃ for 2-8 hours. Finally, the mixture is cooled, dispersed, and sieved to obtain the final product. This invention, through the synergistic effect of seed crystals and composite mineralizer, simultaneously achieves α-phase transformation, densification, grain growth, and morphology control of alumina powder under mild calcination conditions. It successfully prepares alumina powder with an α-phase content ≥96%, true density >3.96 g / cm³, median particle size D50 ≥50 μm, and a regular spherical morphology. This method is simple, low-cost, and the product is suitable for high-filling thermally conductive fillers, showing great promise for industrial application.

This invention discloses a nozzle atomizing device for preparing spherical metal powder, belonging to the field of metal powder technology. The nozzle of this invention features an optimized internal flow channel structure and is made of high-temperature resistant material, which improves the quality and consistency of the metal powder. It includes a molten metal container; a stepped liquid guide tube connected to the outlet of the molten metal container; an inner nozzle with multiple circular holes arranged in a ring below the outlet of the stepped liquid guide tube; and an ultrasonic atomizing device. This invention employs a two-stage device with different structures, an optimized combination of injection angle and a stepped liquid guide tube, achieving a dual, strong atomization effect from the nozzle, which is beneficial for obtaining metal powder with good sphericity and high fine powder yield. The gas atomizing nozzle of this invention is suitable for the production of metal powder, especially in the field of additive manufacturing.

The application discloses an X-MCM-41 mesoporous molecular sieve microsphere adsorbent and a forming method and application thereof, and aims at the forming problem of X-MCM-41 molecular sieve powder in the application of sanitary napkins, urine pads and other products, and provides a technology for preparing 40-60 mesh microsphere adsorbents by atomizing and blowing forming with attapulgite and sesbania gum as a composite binder. The technology comprises the following steps: preparing X-MCM-41 mesoporous molecular sieve powder, preparing atomizable slurry by mixing X-MCM-41 mesoporous molecular sieve powder, attapulgite, sesbania powder and water; obtaining green microspheres by controlling atomization parameters; and obtaining the final product by drying through programmed temperature and constant humidity and roasting under specific conditions. The core contradiction between mechanical strength (toughness, hardness) and mesoporous structure (specific surface area) in the X-MCM-41 forming is solved. The obtained microsphere adsorbent has high strength, low pulverization rate, high specific surface area retention rate, can be directly applied to personal care products, can efficiently adsorb irritating odor molecules such as ammonia, trimethylamine and hydrogen sulfide, and can improve the comfort and safety of products.

The invention relates to hydration heat inhibition particles for concrete and a preparation method thereof. The hydration heat inhibition particles are prepared by wrapping 65-75 wt% of phase change material particles with 25-35 wt% of shell layer composite material powder; the phase-change material particles are composed of 20-40 wt% of a low-temperature phase-change material and 60-80 wt% of a high-temperature phase-change material, the low-temperature phase-change material and the high-temperature phase-change material are subjected to high-temperature melting and uniform mixing, ice water is dripped into the mixture through a dripping nozzle for cooling granulation to prepare the phase-change material particles, then the phase-change material particles are placed in a disc granulator, and the shell composite material is added for granulation. The hydration heat inhibition particle for concrete prepared by the invention is uniform in shell thickness, high in structural stability, high in strength, good in sealing property, excellent in sphericity degree and good in concrete compatibility, and can tolerate 100 times of heat cycles at 20-80 DEG C without cracks; after being doped into concrete, the concrete admixture state can be improved, the temperature gradient in the concrete hydration period is remarkably reduced, and the cracking risk is remarkably reduced.

The invention discloses a synthesis method of porous polylactic acid microspheres, and belongs to the field of biomedical materials. The method comprises the following steps: preparing a first water phase taking a water-soluble polymer as a pore-foaming agent, and dispersing the first water phase in a polylactic acid organic solution to form a water-in-oil-in-water primary emulsion; introducing the primary emulsion into a curing bath containing a poor solvent, so that the organic solvent is extracted, the polylactic acid is cured, and microspheres wrapping pore-foaming agent liquid drops are formed; and finally, washing to remove the pore-foaming agent to form a porous structure. The core of the method is that the internal water-phase liquid drops are used as a sacrificial pore-forming template, and the microspheres are cured by a solvent extraction method. The method is mild in condition, green and environment-friendly, the aperture, porosity, particle size and pore connectivity of the microspheres can be independently and accurately regulated and controlled by adjusting parameters such as emulsification conditions and phase proportion, and the prepared microspheres have the characteristics of open pores and high connectivity and have excellent application prospects in the fields of drug sustained release and tissue engineering.