37results about How to "Antioxidant performance is stable" patented technology

The invention relates to a device for heat shaping of thin-walled titanium alloy parts. A first pressing mechanism is fixed at one end of a body, and a second pressing mechanism is fixed at the other end of the body. Two clamping mechanisms are mounted in the middle of the body. Two clamping plates of a lateral ejection mechanism are fixed on two lateral surfaces of the body respectively and located between the first pressing mechanism and the clamping mechanisms. A width inner-supporting mechanism is located between the two clamping plates of the lateral ejection mechanism, one end of the width inner-supporting mechanism is mounted in a to-be-shaped part, and cavity inner-supporting mechanisms are mounted on the upper surface and the lower surface of the width inner-supporting mechanism. One ends of the cavity inner-supporting mechanisms are mounted in the clamping mechanisms, so that a support body with a wedge-shaped inner cavity is formed in the to-be-shaped part. By the device, utilization rate of a heat treatment furnace is increased, and cost of vacuum heat shaping is lowered. Since the to-be-shaped parts are clamped symmetrically, main stresses of a tooling are symmetric in direction and offset each other, stress state of the tooling is improved, and deformation resistance of the tooling is enhanced indirectly.

Provided is a preparation method of SiOC ceramic aerogel. The invention relates to an aerogel material preparation technology, in particular to a preparation method of the SiOC ceramic aerogel. The problem that for an existing method for preparing the SiOC ceramic aerogel, the aperture is difficult to control is solved. The method comprises the steps that hydrogen-containing polymethylsiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane, chloroplatinic acid and acetone are mixed to be uniform and then put into a hydrothermal reaction kettle for reacting, and gel is obtained; the gel is soaked with acetone and ethyl alcohol in sequence, supercritical drying treatment is conducted, the temperature is increased to 700 DEG C to 1,300 DEG C under a nitrogen or argon atmosphere, heat preservation is conducted for 1 h to 3 h, natural cooling is conducted to room temperature, and the SiOC ceramic aerogel is obtained. The SiOC ceramic aerogel has the advantages of being high in specific surface area, narrow in pore diameter distribution, stable in structure and stable in temperature resistance and oxidation resistance and can be applied to the fields of thermal insulation, energy storage and the like.

The invention discloses a preparation method for copper/silver heterojunction nano-particles. The preparation method comprises the following steps of: (1) adding a reducer in copper salt solution with stirring, and reacting for 1-3 hours; performing centrifugal separation and precipitate extraction on the reaction solution after the reaction is concluded, so as to obtain nano-copper samples; (2) dispersing the nano-copper samples obtained in the step (1) in a solvent, so as to obtain nano-copper solution; then adding silver salt solution in the nano-copper solution, heating to 70-180 DEG C and reacting for 1-6 hours, and performing centrifugal separation and precipitate extraction on the reaction solution after the reaction is concluded, so as to obtain the copper/silver heterojunction nano-particles. According to the preparation method disclosed by the invention, the copper/silver heterojunction nano-particles are prepared by performing a replacement reaction on the surface layer of copper, and the reducer is added to disperse nano-copper during the preparation process, thus solving the technical problem that nano-copper powder is difficult to disperse; moreover, the preparation method is simple in process and low in preparation cost.

The invention relates to a high-flame retardation solar energy cell organosilicon pouring sealant and a preparation method thereof. The high-flame retardation solar energy cell organosilicon pouring sealant comprises the following raw materials in parts by weight: 40 parts of methyl phenyl vinyl silicone rubber, 20 parts of room-temperature sulfured phenylene silicone rubber, 20 parts of addition-type heat vulcanized nitrile silicone rubber, 20 parts of phosphate silicone oil, 20 parts of polyoxypropylene glycerol ether silicone oil, 10 parts of mercapto silicone oil, 5 parts of low-molecular hydroxy silicone oil, 5 parts of hydrogen-containing silicone oil with hydrogen containing amount accounting for 0.5% of mass content, 10 parts of an ethene-vinyl acetate copolymer, 10 parts of otcamethylcyclotetrasiloxane-modified acrylic resin, 7 parts of hydrogenated castor oil, 1-3 parts of an adhesion agent, 1-3 parts of a strengthening agent, 0.1-0.4 parts of a catalyst, 1-3 parts of a silicon nitrogen cross-linking agent, 0.5-2.5 parts of an inhibitor, and 1-2 parts of a flame-retardation filling material.

The invention discloses a composite converter magnesia-carbon brick and a preparation method thereof, and belongs to the technical field of steel making. The magnesia-carbon brick comprises an A part,a C part, and a B part positioned between the A part and the C part; one side surface of the B part is serrated and is tightly engaged with one side surface of the A part, and the other side surfaceof the B part is also serrated and is tightly engaged with one side surface of the C part. The part A is used as a working layer, wherein a high-quality fused magnesia raw material is adopted to forma stable internal network structure with a carbonaceous raw material and a bonding agent, so that integral high-temperature resistance of the magnesia-carbon brick is improved; the B part is used as atransition between the working layer and a non-working area, wherein a high-quality fused magnesia raw material and regenerated magnesia carbon bricks are adopted, so that integral high-temperature resistance of the magnesia-carbon brick is ensured; and the C part is used as a non-working area, wherein the whole C part is prepared by regenerated magnesia-carbon bricks are adopted, so that production cost is reduced. The composite converter magnesia-carbon brick is suitable for popularization and use by enterprises.

The invention discloses a CVD SiC/SiO2 gradient antioxidant composite coating and a preparation method thereof. The CVD (Chemical Vapor Deposition) SiC/SiO2 gradient antioxidant composite coating is mainly used for long-time antioxidant protection of graphite, a C/C composite material and an easily oxidized ceramic-based material (such as a C/C-ceramic composite material, C/ceramic composite material, carbide ceramics and the like). The coating is prepared by adopting a chemical vapor deposition (CVD) method and has good controllability and designability. The coating comprises a SiC coating, a SiO2 coating and a SiC and a SiO2 co-deposition coating. The coating is formed by a gradient or is a multilayer composite gradient coating which is formed by multiple gradients; the multilayer composite gradient coating is sequentially SiC/SiC-SiO2/SiO2 coating from inside to outside, or sequentially SiC/SiC-SiO2/SiC-SiO2/SiC-SiO2/SiO2 coating, or sequentially SiC/SiC-SiO2/SiO2/SiO2-SiC/SiC/SiC-SiO2/SiO2......SiC/SiC-SiO2/SiO2, or SiC/SiC- SiO2/SiO2-SiC/SiC-SiO2/....../SiO2-SiC/SiC-SiO2/SiO2, or SiC/SiC-SiO2/SiC-SiO2/SiO2- SiC/SiC-SiO2/......./SiC-SiO2/SiC-SiO2/SiO2, or is only a SiC-SiO2 codepostion coating. The prepared gradient composite coating has good long-time oxidation resistance at the temperature of from a room temperature to 1700 DEG C.

Objects of the present invention are to provide oxidation resistant nickel-coated copper powder for conductive paste capable of forming a conductive wiring part for an electronic circuit, and to provide a method for producing the same. In order to achieve the objects, there is provided nickel-coated copper powder which is characterized in that it comprises nickel-coated copper particles in which a core material is copper particles, a catalyst for plating is fixed to a surface of the copper-particles by reduction reaction and electroless plated nickel is applied to the outermost surface. The reduction reaction is characterized in that hydrazine is used as a reducing agent.

The invention discloses alkyl-substituted disiloxane shown by a chemical formula (I), and a preparation method thereof. The preparation method of the compound comprises the steps that: raw materials are adopted according to a molar ratio of magnesium to bromoalkane to silicon tetrachloride of 3-3.5:3-3.3:1; magnesium is added into a reaction vessel; bromoalkane-tetrahydrofuran or an anhydrous diethyl ether solution and a silicon tetrachloride-ligroin solution are added under the protection of nitrogen gas; the mixture is subjected to a reaction for 2-6h under a temperature of 20-60 DEG C; an ammonium chloride solution or dilute hydrochloric acid is mixed into the mixture for stopping the reaction; an organic phase is separated from an aqueous phase; the aqueous phase is extracted by using an organic solvent, and the organic phases are combined; the mixture is washed by using deionized water, and is dried by using a drying agent; the material is subjected to pump-filtration; the filtrate is subjected to distillation concentration, and is dehydrated for 3-4h under a temperature of 160-260 DEG C; the material is then subjected to silica gel column chromatography, such that the alkyl-substituted disiloxane is obtained. The alkyl-substituted disiloxane provided by the invention has good thermal stability, good oxidation resistance, and high flash point. The compound is suitable to be used in hydraulic oil, diffusion pump oil, and heat conduction oil.

The invention relates to a whitening agent that makes effective use of camu camu seeds, which have conventionally been discarded, and that has high safety and whitening effect useful in cosmetics and the like, as well as skin preparations for external use and cosmetics containing the whitening agent. The whitening agent of the present invention contains camu camu seed extract as an active component, and the skin preparations for external use and cosmetics of the present invention contain the whitening agent.

The invention relates to a tungsten carbide interface layer modified silicon carbide fiber-reinforced silicon carbide composite material and a preparation method thereof. The method comprises the following steps of: (1) depositing a tungsten carbide interface layer and a silicon carbide interface layer on the surface of a silicon carbide fiber prefab in sequence through a chemical vapor depositionmethod, so as to prepare a modified silicon carbide fiber prefab; (2) steeping the modified silicon carbide fiber prefab prepared in the step (1) by using precursor solution of carbon, and carrying out solidification and pyrolysis on the steeped modified silicon carbide fiber prefab in sequence; (3) repeating the step (2) for at least once so as to obtain a porous silicon carbide fiber prefab; and (4) carrying out liquid silicon infiltration reaction on the porous silicon carbide fiber prefab to obtain the tungsten carbide interface layer modified silicon carbide fiber-reinforced silicon carbide composite material. The prepared tungsten carbide interface layer modified silicon carbide fiber-reinforced silicon carbide composite material is excellent in comprehensive properties such as high-temperature oxidation resistance, thermal shock resistance, vapor corrosion resistance and the like.

The invention discloses a natural compound antioxidant for animal feed and a preparation method thereof. The natural compound antioxidant comprises the following raw materials in percentage by weight:1-5% of astaxanthin, 1-10% of a rosemary extract, 5-20% of lipoic acid, 1-7% of vitamin C, 2-6% of citric acid and the balance of a carrier. The antioxidant disclosed by the invention solves the problem of poor antioxidant effect of the existing feed antioxidant, and can prevent or delay oxidative rancidity of fat in the feed, improve the stability of the feed and prolong the storage period afterbeing added into the high-fat feed.

The invention discloses a phosphorus-free corrosion and scale inhibition all-in-one agent for treating circulating cooling water. The agent is prepared from the following components in percentage by mass: 15-20% of polyepoxysuccinic acid (sodium salt), 20-30% of hydrolyzed polymaleic acid, 20-30% of 2-acrylamide-2-methylpropanesulfonic acid, 5-10% of zinc sulfate and the balance of deionized water. Accroding to the invention, the agent is free of organic phosphonates and inorganic phosphates, is a phosphorus-free product, can be completely biodegraded, cannot cause deterioration of natural environment and biological death or secondary pollution of the ecological environment after discharged into the natural environment along with wastewater of a circulating cooling water system, and is quite environmentally friendly. Compared with an existing mainstream phosphorus formula and a formula requiring for separated adding of a phosphorus-free corrosion inhibitor and a scale inhibitor, the agent of the invention has the advantages that the release amount is small, the release is simple and convenient, the scale inhibition rate is 96% or above, and the corrosion inhibition rate is 95% or above, so that the treatment cost of the circulating cooling water is greatly reduced.

The invention relates to aluminum welding powder and a preparation method thereof. The aluminum welding powder comprises the following raw materials of, by weight, 20-35 parts of barite, 2-5 parts ofsilicon dioxide, 4-10 parts of copper oxide, 4-10 parts of vanadium oxide, 2-5 parts of lithium sulfate, 2-6 parts of calcium fluoride, 1-5 parts of sodium nitrate and 50-70 parts of aluminum powder.The aluminum welding powder has stable oxidation resistance, corrosion resistance and adhesiveness and is free of collapse.

The invention relates to the technical field of chemical industry, in particular to an efficient soldering tin protective agent. The efficient soldering tin protective agent is prepared from, by weight, 5-20% of high-viscosity dimethicone, 5-10% of palmitoleic triolein, 5-10% of arachidonic acid, 5-10% of liquid polybutylene, 40-50% of vacuum residue and 0.5-2% of amine antioxidant. The raw materials are mixed and molten into uniform grease at the temperature of 100-140 DEG C. The efficient soldering tin protective agent is stable in performance.