130results about How to "Uniform grain distribution" patented technology

The invention relates to a method for preparing a flue gas SCR (Selective Catalytic Reduction) denitration catalyst. The method comprises the following steps of: mixing ammonium metavanadate, oxalic acid, manganese salt and water for preparing a mixture solution, adding titanium dioxide powder into the mixture solution, heating in water bath and stirring, and obtaining mixed sol by standing at room temperature; putting the mixed sol into a microwave oven, heating and drying by utilizing microwave radiation; and putting dried solid into a muffle furnace for burning. According to the method disclosed by the invention, a temperature window of the SCR catalyst can be broadened to a low-temperature direction, the problems of low denitration efficiency at low temperature and narrow temperature window of a commercial catalyst are solved; compared with the traditional drying method, the microwave radiation heating and drying method has the advantages that low-temperature SCR denitration activity of the composite catalyst can be increased to a large extend, when the activity temperature is up to 250 DEG C, the denitration efficiency of the catalyst prepared by the traditional drying method is up to 51.9%, and the denitration efficiency of the catalyst can be increased by 31.7 percentage points and can be up to 83.6% by the microwave radiation heating and drying method.

This invention discloses a method for preparing highly (111)-oriented PZT thin film. The method can solve the problems of complex process and low repeatability faced by sol-gel method. The method comprises: preparing PZT sol, depositing PZT thin film, pre-crystallizing PZT thin film, and crystallizing PZT thin film. The method is simple. The obtained PZT thin film has compact and smooth surface, uniform thickness, uniform grain sizes, high residual polarization value (43-60 muC/cm2), low coercive field (60-75 kV/cm), and high saturated polarization value.

The invention provides a method for preparing a high active palladium-carbon catalyst. The method comprises the following steps: palladium chloride is dissolved by hydrochloric acid to be prepared into a solution with certain concentration, then the solution is added into pretreated activated carbon along with an auxiliary agent to ensure that palladium is evenly dispersed on the surface and the subsurface of carbon, and then the high active palladium-carbon catalyst is obtained through the reduction of a reducing agent.

The invention discloses a lithium titanate/porous carbon composite material. The invention further discloses a preparation method of the lithium titanate/porous carbon composite material. The prepapration method comprises the following steps: weighing lithium hydroxide monohydrate, tetrabutyl titanate and porous carbon according to a certain stoichiometric ratio; adding ethanol and de-ionized water and uniformly mixing; transferring a stirred suspension solution into a hydrothermal reaction kettle and reacting at 180 DEG C for 24h to 48h to obtain precursor slurry; drying and crushing the precursor slurry to obtain precursor powder; treating the precursor powder in an inert atmosphere at the temperature of 500 DEG C to 700 DEG C for 5 to 10 hours to obtain the lithium titanate/porous carbon composite material. The composite material prepared by the technical scheme provided by the invention has excellent rate performance and low-temperature property.

The invention relates to a preparation method of a polycrystalline silicon ingot. The method comprises the following steps: (1) a binding agent, a dispersing agent, and silicon particles of which the purity is above 99.9 percent and the diameter is between 1 [mu]m and 5,000 [mu]m, are added into deionized water, a pulp is obtained after uniform mixing, and the mass percentage of the silicon particles in the pulp is not less than 50 percent; (2) in a quartz crucible with a silicon nitride coating on the inner surface, the pulp is applied on the surface of the silicon nitride coating through spray coating, roller coating or brush coating, so as to form a pulp layer with a thickness between 1 mm and 10 mm; the crucible with a silicon coating is obtained after drying; (3) the crucible with the silicon coating is sent into a polycrystalline silicon ingot furnace after being loaded with silicon materials, the silicon materials are heated after vacuum pumping, a silicon material melt is cooled for polycrystalline silicon growth after the silicon materials are completely molten, and the polycrystalline silicon ingot is obtained through annealing cooling after the polycrystalline silicon growth is completed. The polycrystalline silicon ingot obtained through the method can be used for the manufacturing of a solar battery, so that the average battery efficiency of a silicon wafer exceeds 18 percent.

Disclosed is a microwave synthesis method of nickel phosphates cobalt cellular materials. The steps comprise preparing nickel source substance, cobalt source substance, phosphorus source substance, template, mineralizer and water according to oxide molecular ratio, initially dissolving the nickel source and the cobalt source in the water, adding with the phosphorus source when stirring, then adding with the template and the mineralizer and continuing to stir evenly, moving the reaction solution into a microwave synthesis reactor, irradiating for 3-360 minutes step by step under the temperature of 130-180 DEG C, then centrifugal separating, washing and freeze-drying, and thereby the nickel phosphates cobalt CoVSB-1 materials is obtained. The frequency of the microwave is 2450 megahertz, and the power is 400-1000 watt. A microwave is heated by employing the temperature controlling mode. Compared with the conventional hydro-thermal method, the synthesis time of the invention is shorter, the grain size distribution is more uniform, and the reducing of the size of crystal grain is in favor of the increasing of the catalytic performance of the product.

The invention relates to high-performance composite calcium sulfonate based lubricating grease and a preparation method thereof. The composite calcium sulfonate based lubricating grease is prepared from the following raw materials: high-alkali-value calcium sulfonate, base oil, lauric acid, low-molecular alcohol, high-purity water, boric acid, calcium hydroxide, antioxidant and HL-functional agent. The composite calcium sulfonate based lubricating grease provided by the invention has the characteristic of excellent high-temperature resistance, water resistance and extreme pressure wear resistance; and in particularly, the converted calcium carbonate is uniform in crystalline grain distribution, so that the product is very stable in structure, thus solving the problem of the surface hardening of the composite calcium sulfonate-based lubricating grease.

The invention discloses (Hf,Ta,Nb,Ti)B2 high-entropy ceramic powder and a preparing method thereof. The preparing method comprises the steps of 1, weighing HfO2 powder, TiO2 powder, Nb2O5 powder, Ta2O5 powder, B4C powder and C powder as raw materials, then mixing the raw materials, and grinding the raw materials to obtain mixed powder; 2, sintering the mixed powder obtained in step 1, introducinginert gas in the sintering process, conducting cooling after sintering is finished, and finally, obtaining the (Hf,Ta,Nb,Ti)B2 high-entropy ceramic powder. The method has the advantages that the process is simple, the production cost is low, the synthesized powder is fine in crystal grain, uniform in distribution and high in purity, and the oxygen content is lower than 0.53 wt%, all of which endowthe method with the potential of developing large-scale industrial production.

The invention provides a preparation method of low-loss nano crystal soft magnetic alloy. In the method of the invention, when crystallization heat treatment is performed on a strip obtained in a quenching technology, a heat treatment process is divided into four steps: step I, applying a magnetic field for thermal insulation in a copper cluster precipitation temperature zone along a length direction of an alloy strip; step II, performing thermal insulation in an optimum potential heat release temperature zone under a magnetic-field-free condition; step III, applying the magnetic field for thermal insulation in an optimum crystallization and growth temperature zone of alpha-Fe-phase nano crystal grains; and finally, applying the magnetic field for thermal insulation at a temperature less than the copper cluster precipitation temperature along a width direction of the strip. Compared with an existing heat treatment method, the method can reduce the high-frequency loss of the nano crystal soft magnetic alloy and can improve the comprehensive performance of the nano crystal soft magnetic alloy.

The invention discloses a biomass charcoal/iron oxide composite material for a lithium battery negative electrode, and a preparation method thereof in order to solve the problems of large volume expansion ratio and poor cycle performance of a lithium battery negative electrode material iron oxide. The preparation method comprises the following steps: carbonizing leaves, barks, wood chips and/or animal hair to prepare biomass charcoal, compounding the biomass charcoal with iron oxide by a forced hydrothermal process in order to obtain a porous biomass charcoal-coated iron oxide precursor, and performing microwave treatment on the precursor to change the crystallinity of the iron oxide in order to obtain the biomass charcoal/iron oxide composite material. The biomass charcoal/iron oxide composite material prepared in the invention has a low cost, can be directly applied to the electrode materials of lithium ion battery negative electrodes, and has wide practical application values and industrial production prospects.

The invention discloses a production process of a specially-shaped pipe. The production process of the specially-shaped pipe comprises the following steps: selecting a pipe, grinding ends of the pipe, annealing for a first time, pickling with acid for a first time, washing for a first time, phosphatizing for a first time, washing for a second time, saponifying for a first time, cold drawing for a first time, annealing for a second time, pickling with acid for a second time, washing for a third time, phosphatizing for a second time, washing for a fourth time, saponifying for a second time, cold drawing for a second time, straightening and carrying out antirust treatment. The production process of the specially-shaped pipe is characterized by firstly cold drawing a billet pipe in inner and outer circular dies so as to reduce the outer diameter of the wall thickness of the billet pipe, so that the inner and outer surfaces of the billet pipe are more smooth; the quality during cold drawing for the second time is improved; grains in the billet pipe subjected to cold drawing for the first time are unevenly distributed in the presence of stress; through annealing, the grains in the billet pipe are evenly distributed and the stress is removed, so that the breakage of the billet pipe when the billet pipe is subjected to cold drawing for the second time is avoided.

The invention discloses a novel nanometer titanium dioxide self-cleaning fluorine-carbon aluminum single sheet as well as a low-temperature preparation method and application thereof. The surface of the fluorine-carbon aluminum single sheet is coated with a self-cleaning nanometer titanium dioxide film or a nanometer titanium dioxide and silicon dioxide composite film; the film is uniformly distributed on the surface of the fluorine-carbon aluminum single sheet, and thickness of the film is 1-3 micrometers; and after being irradiated by ultraviolet light, the nanometer titanium dioxide film has super-hydrophilic property and photocatalytic property, thus, the self-cleaning effect is realized. The novel nanometer titanium dioxide self-cleaning fluorine-carbon aluminum single sheet related in the invention has the following advantages: (1) the thickness of the titanium dioxide film is uniform, nanometer titanium dioxide crystal particles are uniformly distributed, and the titanium dioxide film has super-hydrophilic property and a better self-cleaning function; (2) the film has photocatalytic property, so that residual organic pollutants on the surface of the film can be decomposed, and the self-cleaning effect is further improved; and (3) the original performances, such as weatherproof performance, chemical corrosion resistance and the like, of the fluorine-carbon aluminum single sheet are retained.

The invention relates to the field of microwave medium ceramic of material science, in particular to Ba(Zn1/3Nb2/3)O3(BZN)-based microwave medium ceramic sintered by low-temperature reaction and a preparation method thereof. The method comprises the following steps of: adding the following additives in percentage by mass into a Ba(Zn1/3Nb2/3)O3(BZN) base material: 0.5 to 1.5 percent of CuO, 0.5 to 1.5 percent of Li2CO3, 0.5 to 1.5 percent of V2O5 and 1.5 to 4.5 percent of ZnO-B2O3; and performing common ball-milling and mixing, drying, screening and compression molding on the mixture, and then obtaining a dense ceramic product by reacting and sintering the mixture, wherein the sintering temperature can be reduced to 950 DEG C. The microwave medium ceramic has good microwave performance, and reduces the energy consumption and the cost.

The invention relates to an isothermal die forging technology for large-size high-strength aluminum alloy parts, and belongs to the technical field of aluminum alloy machining. According to the isothermal die forging technology, large-size aluminum alloy forging cake blanks undergo isothermal die forging formation in one step after being heated and thermally insulated for obtaining forge pieces, the forge pieces are taken out and cooled, and finally finished products are obtained; in the isothermal die forging process, the descending speed of upper dies is 0.1-0.2 mm/s. By selecting raw materials and strictly controlling forging parameters, continuous large deformation is realized on the condition that alloy crystal grains do not grow, and the large-size and high-performance aluminum alloy parts can be prepared with high efficiency and low cost. The isothermal die forging technology has the advantages that the operation is easy, the production efficiency is high, the product quality is high and the practicability is high, thereby being suitable for industrialized use and popularization.

The invention relates to the technical field of lithium ion battery manufacturing, and particularly relates to a method for preparing a molybdenum dioxide coated lithium titanate negative electrode material. The method comprises the following steps: dissolving lithium acetate and polyvinylpyrrolidone in distilled water, adding nano titanium dioxide, and carrying out magnetic stirring for 1 h so as to obtain a slurry; carrying out spray drying on the slurry so as to obtain a lithium titanate precursor; roasting the precursor for 8 h at a temperature of 750 DEG C in an air atmosphere so as to obtain a pure lithium titanate negative electrode material; dissolving ammonium molybdate and a tartaric acid in distilled water, adding the pure lithium titanate negative electrode material, and carrying out magnetic stirring for 1 h; after solvents are dried by distillation at a temperature of 100 DEG C, carrying out vacuum drying on the obtained object for 1 h at a temperature of 80 DEG C, so that a molybdenum dioxide coated lithium titanate precursor is obtained; and roasting the molybdenum dioxide coated lithium titanate precursor for 6 h at a temperature of 600 DEG C in an argon atmosphere, so that a molybdenum dioxide coated lithium titanate negative electrode material is obtained. The method disclosed by the invention is simple and safe in process, and low in cost, and the obtained molybdenum dioxide coated lithium titanate negative electrode material has good electrochemical properties.

The invention provides a nickel oxide and barium titanate nano composite ferroelectric film material and a preparation method and application thereof. A film has the (001) face crystal orientation andcomprises, by volume percentage, 10-30% of nickel oxide and 70-90% of barium titanate. The preparation method comprises the steps of preparing the barium titanate, the nickel oxide and a nickel oxideand barium titanate composite target material through a solid phase deposition method; and then adopting a pulsed laser deposition method, and preparing the nano layered nickel oxide and barium titanate nano composite ferroelectric film, the nano columnar nickel oxide and barium titanate nano composite ferroelectric film and the nano granulated nickel oxide and barium titanate nano composite ferroelectric film by controlling deposition parameters. The nickel oxide and barium titanate nano composite ferroelectric film material and the preparation method and application thereof are simple in process. The obtained nano composite film has the beneficial effects that the microstructure is continuous and adjustable; nanoscale crystalline grains are distributed uniformly; the film thickness canbe controlled precisely; and crystal orientation extends outwards. Ferroelectric performance of the composite film material is effectively improved; dielectric performance is enhanced; the obtained high-performance material can be applied to the fields of ferroelectric storage devices, supercapacitors, crystalline field effect tubes, acoustic surface wave devices and the like; and the applicationscope is wide.

The invention discloses an annealing method of a ceramic rear cover, and belongs to the field of ceramic rear cover machining. The method comprises the following steps: putting the ceramic rear coverinto an annealing furnace, rising the temperature to a 600 to 800 DEG C medium temperature zone, and performing heat preservation for 1 to 2 hours; rising the temperature to a 1000 to 1200 high temperature zone after heat preservation is performed in the medium temperature zone, and performing heat preservation for 3 to 4 hours in the high temperature zone; reducing the temperature to 800 to 900 DEG C after high temperature preservation is performed, and ensuring that the time is controlled to be 1 to 2 hours; naturally cooling the ceramic rear cover to the room temperature, and then discharging the ceramic rear cover, so as to accomplish annealing. The method has the benefits that a gradient temperature rising and reducing technology is adopted; through twice time rise and twice temperature reduction, the ceramic rear cover is kept in the two temperature zones for a certain period of time, then crystal particles inside the ceramic rear cover are grown by stages, interaction force among the crystal particles is fully released, the crystal particles are more uniformly distributed, and an arrangement structure among the crystal particles is more stable, so that stress produced duringfine carving of the ceramic rear cover is effectively reduced, the fact that the deformation of the ceramic rear cover is below 0.08mm after annealing treatment is ensured, and the assembly requirement of mobile phones is met.

The invention discloses a method for preparing a nitrogen-carbon co-coated lithium titanate anode material. The method specifically comprises the following steps: 1) ball-milling lithium carbonate, titanium dioxide and melamino-formaldehyde in acetone for 6 hours, uniformly mixing, transferring into a vacuum drying box at the temperature of 100 DEG C, and drying to obtain a lithium titanate/nitrogen-carbon composite precursor; 2) roasting the lithium titanate/nitrogen-carbon composite precursor in argon at 750 DEG C for 8 hours to obtain the nitrogen-carbon co-coated lithium titanate anode material. The method is simple and safe in process and low in cost, and the prepared nitrogen-carbon co-coated lithium titanate anode material is fine and uniform in granule and relatively good in electrochemical property.