54results about How to "Inhibit aggregate growth" patented technology

The invention relates to a W-Cu composite material with high Cu content and the preparation method of the W-Cu composite material. The W-Cu composite material is characterized in that due to the improvement of raw materials and a technology, the prepared composite material has high Cu content reaching up to more than 70% and has the characteristics of uniform structure and high compactness.

The invention relates to a supported gold-PGM alloy catalyst with stable storage property and a preparation method thereof. An active component is Au, an accessory ingredient is Pd or Pt in PGM, and a carrier is a Al2O3 composite oxide modified by Al2O3 or MIOx and MIIOx, wherein the atomic ratio of Au to PGM is 1.0:1.0-1.0:1.0*10<-2>; the atomic ratio of Au to MI+MII is 1.0:1.0-1.0:10; the atomic ratio of MI to MII is 2.0:1.0-0.2:1.0; the atomic ratio of Au to Al is 1.0:1.0*10<3>-1:0:10; MI is La; and MII is Fe, Co or Ni. The composite oxide carrier is prepared by an impregnation method or a coprecipitation method. After being supported with MIOx and MIIOx, Al2O3 is roasted at a temperature of between 800 and 1,000 DEG C to generate a spinelle or perovskite structure. The catalyst of the invention catalytically oxidizes micro CO (0.1 percent to 1.5 percent) in the air into CO2 at ambient temperature and in ambient humidity, and has the advantages of stable catalysis property, pressure drop meeting the requirements of a gas mask and a mining self-rescuer and low cost.

The invention relates to a hierarchical pore nanometer flower-like structure Ag catalyst of methyl glycolate prepared through oxalic ester hydrogenation. Titanium-doped hierarchical pore nanometer flower-like silica balls are taken as a carrier, and silver is taken as an active ingredient; the weight percentage of the components in the catalyst is as follows: the weight percentage of the active ingredient such as silver is equal to 5 wt% to 20 wt%, the weight percentage of an additive such as TiO2 is equal to 0.5 wt% to 2.5 wt%, and the balance is silicon oxide; the preparation method comprises the following steps: adding a mixed liquor containing a silicon oxide precursor into a template mixed liquor, adding a titanium precursor after uniform stirring, carrying out hydrothermal crystallization, taking a product to carry out centrifugal separation and washing, vacuum drying and calcinations to obtain a hierarchical pore nanometer flower-like titanium silicon compound carrier; and adding a soluble silver precursor solution into the carrier, stirring, aging, and finally carrying out calcinations and reduction on an obtained drying product. The catalyst is of a hierarchical pore nanometer flower-like structure, so that the accessibility of active metal silver can be improved; and besides, the carrier is regulated and controlled by adopting titanium, and the dispersity of silver is improved through mutual effect of silver and titanium, so that the hydrogenation reaction activity of oxalic ester and the selectivity of methyl glycolate are strengthened.

The invention relates to a solid solution catalyst for acetic acid self-heating hydrogen production by reforming. Aiming at the problem that in an acetic acid self-heating reforming reaction of an existing catalyst, by means of oxidizing, sintering, carbon depositing and other factors of the active components of the catalyst, the catalyst is inactivated, the novel catalyst is stable in structure, resistant to sintering, resistant to carbon depositing and oxidization and stable in activity, and the composition by weight of the catalyst is (NiO)a(YO1.5)b(ZrO2)c, wherein a ranges from 0.07 to 0.20, b ranges from 0.02 to 0.35, and c ranges from 0.58 to 0.91. According to the catalyst, zirconium oxide is adopted as a carrier, an aid yttrium oxide is introduced, a polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer is adopted as a template, a mesoporous structure is formed through evaporation self-assembly, and the nickel-based catalyst with the stable ZrxY1-xOy solid solution as the main structure is obtained. The hydrogen productivity, stability and carbon depositing resisting capacity of the acetic acid self-heating reforming process are effectively improved.

The invention discloses a preparation method of a high-strength alumina ceramic substrate, and belongs to the technical field of ceramic substrate preparation. Carbon dioxide is introduced into a sodium aluminate solution, then ultrafine aluminum hydroxide crystal grains can be formed, the ultrafine aluminum hydroxide crystal grains are mixed with a precursor sol, and tape casting is performed toobtain a tape-casted raw material tape with good cohesiveness. Because the thermal expansion coefficient of the sol is high, the bonding toughening effect is played, and thus cracking and deformationof the alumina ceramic substrate during sintering molding are avoided; mullite whiskers can grow after the sol in micro through holes of the alumina ceramic substrate is sintered and then cooled, alumina particles of the alumina ceramic substrate are wound by the whiskers, the whiskers are beneficial for uniform distribution of internal stress, the relative displacement between alumina and the silicate crystal grains is reduced, and the whiskers can inhibit aggregation and growth of the crystal grains and can effectively reduce pores in ceramics, so that the compactness of a sintered body is improved, the crystal grains in the alumina ceramic substrate are distributed uniformly, the crystal grain distribution is compact, the mechanical strength is enhanced, and the application prospect isbroad.

The invention discloses a method for preparing a carbon-loading noble metal catalyst by a solvothermal method. The method comprises the following steps: I, pre-treating activated carbon; II, uniformlydispersing a water soluble noble metal compound and the pre-treated activated carbon in a solvent to obtain mixed slurry; III, putting the mixed slurry in a closed pressure container, and keeping thetemperature for 2-24 hours at 140-240 DEG C; and IV, naturally cooling the insulated closed pressure container to filter a product in the closed pressure container, and washing the filtered intercepted objects with deionized water to obtain the carbon-loading noble metal catalyst. The carbon-loading noble metal catalyst which is high in dispersibility is prepared by means of the solvothermal method. A novel concept is provided for preparing the carbon-loading noble metal catalyst. By taking ethylene glycol and water or formamide and water as a solvent, a series of carbon-loading noble metal catalysts which are high in dispersibility are prepared by means of high-temperature reducibility of ethylene glycol and formamide and the complexing ability with noble metals.

The invention discloses a lithium ion battery ternary cathode material modified by nanometer SnO2 and a preparation method of the lithium ion battery ternary cathode material. The chemical formula of the ternary cathode material is LiaNixCoyMnzO2, wherein a is not less than 0.9 and not greater than 1.2, and (x+y+z) is equal to 1; the particle dimension of the nanometer SiO2 is 5nm-100nm; the mass ratio of the nanometer SnO2 to the ternary cathode material is 0.01-0.08; nanocarbon is selected as a carrier for separately carrying out a particle growth process and a modification process of the nanometer SnO2. The preparation method disclosed by the invention can be used for precisely controlling the content of a modifier, and improving the material repeatability and consistence; moreover, the prepared lithium ion battery ternary cathode material modified by nanometer SnO2 has higher capacity, rate performance and cycle performance.

The invention relates to a regulating method of a nano layered MgFe hydrotalcite grain growth process. The regulating method of the nano layered MgFe hydrotalcite grain growth process comprises the steps as follows: (1) an Mg(NO3)2 solution and a Fe(NO3)3 solution are prepared and uniformly mixed, so that the molar ratio of Mg to Fe in the solution is (1:10)-(10:1); (2) a NaOH precipitant is dropwise added to the prepared solution in step (1), and the solution is continuously stirred, so that the pH of the solution is 8-12; (3) crystallization is performed at 40-220 DEG C for 0.5-6 h, crystallization is continuously performed at 70-120 DEG C for 12-36 h, the addition quantity of organic steric hindrance agents in a hydrothermal synthesis system is 0.1%-20.0% of the total mass of the solution, a solid product is obtained through separation after the reaction, washed and separated, the obtained solid product is dried, and nano layered MgFe hydrotalcite can be obtained. The nano MgFe hydrotalcite with the narrower crystal size distribution range can be prepared.

The invention discloses a copper-iron alloy modifier which is characterized by comprising a modifier A which comprises, in percentage by mass, 15-25wt% of one or more of copper powder, iron powder and yttrium powder, and the balance copper-calcium alloy powder and inevitable impurities; the content of calcium in the copper-calcium alloy powder is 50wt% or above; and the copper-iron alloy modifier further comprises a modifier B which comprises, in percentage by mass: 10-30wt% of Cu, 20-30wt% of one or more of Te, Mg, Ca, Si and La, and the balance of Fe and inevitable impurities. The modifier B and the modifier A can mutually promote the refinement and spheroidization of crystal grains, a copper-iron alloy phase structure with evenly distributed iron phases can be obtained, the copper-iron alloy with Fe smaller than or equal to 90 wt% can be prepared, ultra-fine wires can be conveniently machined, and the problem of iron phase breaking is solved.

The invention belongs to the technical field of the preparation of positive materials for lithium-ion batteries, and specifically provides a method for preparing a lithium-rich positive electrode material 2x / 3Li2MnO3*(1-x)LiMO2 through an adjustable low temperature combustion method, wherein x is greater than 0 and smaller than 1, and M is Ni, Co and Mn. The method comprises the following steps: dissolving an Ni-Co-Mn metal salt into a solvent according to a stoichiometric proportion, adding a certain amount of a reducing agent and a certain amount of an additive, stirring uniformly, dropwiseadding an appropriate amount of ammonia water to adjust PH so as to obtain a solution A; After heating and evaporating the solution A for a certain period of time, putting the solution A in a heatingfurnace so that the heating furnace is combusted at the temperature of 300 to 700 DEG C to obtain powder B, collecting and grinding the B, putting the powder B in a muffle furnace for combustion for 5to 24 h at the high temperature of 700 to 1100 DEG C, and carrying out ball-milling sieving after cooling to obtain the lithium-rich positive electrode material. The preparation method is simple andquick, various elements in the solution can be mixed in a molecular level, the ultrafine nanoscale material can be prepared, the energy consumption is low, the reaction can be adjusted through parameters, the synthesizing cost of the lithium-rich positive electrode material is greatly reduced, and the rate capability and cycle performance of the lithium-rich positive electrode material are also obviously improved.

The invention relates to a W-Cu composite material with high Cu content and the preparation method of the W-Cu composite material. The W-Cu composite material is characterized in that due to the improvement of raw materials and a technology, the prepared composite material has high Cu content reaching up to more than 70% and has the characteristics of uniform structure and high compactness.

The invention relates to a supported gold-PGM alloy catalyst with stable storage property and a preparation method thereof. An active component is Au, an accessory ingredient is Pd or Pt in PGM, and a carrier is a Al2O3 composite oxide modified by Al2O3 or MIOx and MIIOx, wherein the atomic ratio of Au to PGM is 1.0:1.0-1.0:1.0*10-2; the atomic ratio of Au to MI+MII is 1.0:1.0-1.0:10; the atomic ratio of MI to MII is 2.0:1.0-0.2:1.0; the atomic ratio of Au to Al is 1.0:1.0*103-1:0:10; MI is La; and MII is Fe, Co or Ni. The composite oxide carrier is prepared by an impregnation method or a coprecipitation method. After being supported with MIOx and MIIOx, Al2O3 is roasted at a temperature of between 800 and 1,000 DEG C to generate a spinelle or perovskite structure. The catalyst of the invention catalytically oxidizes micro CO (0.1 percent to 1.5 percent) in the air into CO2 at ambient temperature and in ambient humidity, and has the advantages of stable catalysis property, pressure drop meeting the requirements of a gas mask and a mining self-rescuer and low cost.

The invention provides a composite material of in-situ growth of ternary cobalt-nickel-molybdenum oxide on graphene and a two-step synthesis method thereof, and relates to the field of composite materials of graphene and metal oxides, and the composite material uses graphene as a substrate The cobalt oxide nanorods combined with the rod-like structure are grown in situ on the graphene substrate; the nickel-molybdenum oxide nanorods combined with the rod-like structure are grown in situ on the cobalt oxide nanorods. In the composite material provided by the present invention, the extremely thin graphene increases the specific surface area of ​​the material and increases the utilization rate of the active material; the graphene connects the cobalt oxide materials together to make the material conduct as a whole, avoiding the problem caused by the electrical conductivity. The failure of the material caused by weakness; the well-defined structure avoids the agglomeration of the material, forms a three-dimensional loose and porous morphology, further increases the specific surface area of ​​the material, and improves the capacitance of the material.

The invention relates to a loofah complex oil absorb material. The preparation process is free from harmful and toxic pollutant and has the advantages of simple operation and high efficiency. Loofah is combined with grapheme, so as to obtain the complex oil absorb material with large pore structure and good air permeability, and can be reused for many times. The loofah complex oil absorb materialprepared by the invention has high oil absorbing property and reuse effect, and can be applied to marine oil pollution treatment and oil fume exhaust gas purification.

The invention relates to a bicontinuous composite material which has excellent comprehensive properties due to the special interpenetrating network structure. Aiming at the silicon aluminum material having wide application prospects, the invention implements a silicon-aluminum bicontinuous composite material and a powder metallurgy preparation technique thereof. The technique overcomes the defects of overgrowth of silicon, and material nonuniformity and noncompactness in the casting method and liquid phase impregnation method, and prepares the bicontinuous composite material with controllable composition, phase dimensions and microstructure. The invention implements uniform mixing of the two phases silicon and aluminum by selecting reasonable composition and powder size; and the alloy elements of the aluminum alloy are added by an element powder direct mixing method. The billet is completely compacted within a proper temperature range; and silicon atoms are diffused, so that the silicon powder particles are connected with each other and interpenetrate with the aluminum alloy to form the bicontinuous composite material. The silicon content in the composite material is 40-80 vol.%; and the composite material is completely compact and has a uniform structure. The composite material has excellent comprehensive properties, and is applicable to various conventional machining means.