33results about How to "Inhibit excessive oxidation" patented technology

The invention provides a magnesium-based brazing filler metal alloy with low working temperature and favorable welding performance as well as a preparation method thereof. The alloy comprises the following components in percentage by weight: 0.5-1.1 percent of Al, 51-60 percent of Mg, 0.5-3 percent of Sn, 0.001-0.003 percent of Be, 0.001-0.003 percent of Te, 0.1-0.4 percent of La, 2.6-8 percent of Bi, and the balance of Zn. The preparation method of the magnesium-based brazing filler metal alloy comprises the following steps: dispensing all materials according to weight percentage; heating and melting the dispensed materials in an electric stove crucible under the SF6 protective atmosphere, wherein the weight percentage of La in the middle alloy from Mg to La is 15 percent; preserving the temperature for 5-10 minutes when the temperature rises to 680-700 DEG C; and casting in a steel ingot mould which is preheated to 200 DEG C and then cooling to obtain the magnesium-based brazing filler meta alloy.

A processing apparatus is provided in which a laser beam L2 is irradiated onto a processing portion of a workpiece W, and at the same time as the laser irradiation, an assist gas G is injected toward the processing portion from a nozzle 3 arranged concentric to the laser beam L2 so that the processing portion is covered with the assist gas G, thereby processing a piercing hole H on the processing portion. The apparatus includes control means 10 for processing a piercing hole H while moving the nozzle 3 within the range of 5 mm from a processing start point after the irradiation of the laser beam L2 is started.

The invention provides a zinc-magnesium based brazing alloy with low working temperature and good welding performance and a preparation method thereof. The alloy comprises the following components in percentage by weight: 1.2-1.9 Al, 33-37 Mg, 3.1-6 Sn, 0.0031-0.006 Be, 0.025-0.095 Pr, 0.5-2.5 Bi and the balance of Zn. The preparation method comprises the following steps: heating and melting matched material in a N2 mixing protective atmosphere; firstly, putting Al ingots and Sn strips at the bottom of a crucible; then adding pure Be blocks, Mg-Pr intermediate alloy and pure Bi powder; subsequently adding Mg ingots; and finally adding Zn ingots; keeping the temperature for 4-8 minutes when reaching to 700-725 DEG C, and then casting into a steel ingot mold preheated to 200 DEG C, thereby obtaining the zinc-magnesium based brazing alloy, wherein the weight percent of Pr in the Mg-Pr intermediate alloy is 8 percent.

The invention discloses a preparation method of perfluoro-2-methyl-3-pentanone. According to the method, perfluoro-2-methyl-2-amylene is used as a raw material to be subjected to gas-phase reaction with a certain amount of oxidative gas such as oxygen or air in a fixed bed reactor under the catalyst existence condition; the perfluoro-2-methyl-3-pentanone is directly prepared through one-step or two-step gas-phase reaction, wherein the two-step gas-phase reaction mainly includes perfluoro-2-methyl-2-amylene epoxidation reaction and epoxidation compound gas-phase isomerization reaction. By using the technology, the fixed bed reactor process is used for continuously performing the gas-phase reaction; solvents are not needed in the production process; the cost is greatly reduced; the environment pollution problem is solved; the process safety is improved; meanwhile, the problems of separation of solvents from products, recovery treatment of solvents and catalysts and the like are also avoided. Therefore the preparation method has the characteristics that the cost is low, the preparation is convenient, technical parameters of the catalyst reaction process can be easily controlled, the product separation and purification are simple, the preparation method is very suitable for industrial production and the like.

The invention discloses a selenium-doped lithium-rich manganese-based positive electrode material as well as a preparation method and application thereof. In the structure of the selenium-doped lithium-rich manganese-based positive electrode material, selenium in an anionic form is distributed in a lithium-rich manganese-based positive electrode material, the chemical general formula of the positive electrode material is mLi2MnO3-delta Se2 delta/3.(1-m)LiTMO2-deltaSe2delta/3, TM is at least one of Ni, Co and Mn, 0.2 <= m <= 0.8, and the delta is greater than 0 and lower than 2; and the contentof selenium in the positive electrode material is 0-5% in percentage by mass. The positive electrode material has relatively good lattice stability and electrode/electrolyte interface stability, notonly can inhibit lattice oxygen loss in a circulation process, but also can inhibit electrolyte decomposition, relieves the capacity attenuation and the voltage drop of the lithium-rich manganese-based positive electrode material in the circulation process, and effectively overcomes the problems of poor rate capability and the like of existing positive electrode materials. The preparation method is simple and easy to popularize.

The invention relates to a method for preparing formic acid by catalyzing and oxidizing biomass using oxygen in the presence of FeCl3 (or Fe2(SO4)3)-NaVO3-H2SO4 as a catalyst system in an aqueous solution. The method uses FeCl3 (or Fe2(SO4)3)-NaVO3-H2SO4 as the catalyst system, and oxygen as an oxidant to selectively oxidize biomass in the aqueous solution to prepare high-yield formic acid. Compared with the method for preparing formic acid by catalyzing and oxidizing biomass in an NaVO3/H2SO4 system, the method provided by the invention has the advantages that in the FeCl3 (or Fe2(SO4)3)-NaVO3-H2SO4 system, the catalytic performance of the NaVO3-H2SO4 system can be improved by adding a ferric salt, and the synergistic catalysis between the ferric salt and sodium metavanadate occurs to improve the yield of the formic acid.

The invention discloses an anion-cation co-doped high-nickel single-crystal ternary positive electrode material as well as a preparation method and application thereof. The molecular formula of the anion-cation co-doped high-nickel single-crystal ternary positive electrode material is Li1+aNixCoyMnzMaO2-bOb; wherein M is one or more of Mg, Sf, Al, Zr, Nb, Ta, Mo, Ti, Y, W and V; Q is one or more of F, N, P, S and Se; 1 > x > y > = z > 0, x > = 0.5, and x + y + z = 1. The element Q and the element M of the anion and cation co-doped high-nickel single-crystal ternary positive electrode material replace the site of oxygen and the sites of transition metal nickel, cobalt and manganese respectively, so that the capacity fading and the voltage drop of the high-nickel single-crystal ternary positive electrode material in the cycle process can be inhibited, and the cycle stability, the thermal stability and the intrinsic conductivity can be improved; The rate capability is improved, so that the capacity fading and microcracks of the high-nickel ternary positive electrode material in the circulation process can be effectively inhibited.

The invention provides a preparation method of a catalyst for preparing methanol by low-temperature plasma-optical coupling methane and a method for preparing methanol. The method comprises the following steps: adding 0-20mg of a Cu-C catalyst into 1-5mL of water, carrying out uniform ultrasonic dispersion so as to obtain a mixed solution, pouring the mixed solution into a DBD reactor, and carrying out a reaction under normal temperature and normal pressure so as to obtain the methanol wherein the flow rate of CH4 is 5-30mL/min, and the discharge power is 5-50W. According to the method, low-temperature plasma is adopted to catalyze CH4 and H2O to prepare methanol through one-step conversion, H2O which is low in price and easy to obtain is selected as an oxidizing agent, excessive oxidationof CH4 is restrained, H2O can serve as an absorbent, generated CH3OH is transferred into a liquid phase in time, and decomposition of products is effectively restrained. As the plasma can generate high-energy electrons, CH4 can be activated at normal temperature and normal pressure, and harsh reaction conditions are avoided.

The invention relates to a method for inhibiting pyrite oxidation in a biological metallurgy process. According to the method, an inhibitor is added into ores in the biological leaching process, so that the activity of a ferrous oxidation microorganism is inhibited, and therefore excessive oxidation of the pyrite in the ore biological leaching process is inhibited; and the inhibitor comprises an anionic surfactant and an auxiliary agent, wherein the auxiliary agent comprises one or the combination of at least two of the following agents of an enzyme activity inhibitor, a deoxidizing agent anda heterotrophic microbial accelerator; the method has the advantages that excessive dissolution of the pyrite is inhibited, and excessive accumulation of acid iron is controlled from the source; and the leaching rate and the final leaching rate of target metal can be improved, and cost is reduced.

The invention belongs to the technical field of foods, and particularly relates to a preparation method of alkalescent sweet tea wine. Aiming at the current situation that in an existing sweet tea wine market, no preparation method of the alkalescent sweet tea wine exists, the alkalescent sweet tea wine is prepared through the novel preparation method that sweat tea leaves, rice-flavor wine, mineral water, glucose powder and baking soda are used as the raw materials and subjected to extraction, mixing, filling, inspection, encasement and achievement of the finished product. The product reserves natural nutritious components of the sweat tea leaves, the PH value is adjusted to 7.30-7.45 through the baking soda, the alkalescent sweet tea wine is similar to the human body blood and body liquid in alkalescence so that the alkalescent sweet tea wine can be more easily converted and absorbed by the human body, and the alkalescent sweet tea wine has certain restoration and inhibition effects on radiation injury to an organism and free radical generation of the organism; and in addition, the alcohol content is low and is 12-15%VOL, and therefore the alkalescent sweet tea wine can be more easily accepted by extensive consumer groups and is a healthy drink suitable for people of all ages.

The invention discloses a vanadium oxide/TS-1 heterogeneous catalyst obtained by combining vanadyl acetylacetonate and a TS-1 type titanium-silicon molecular sieve. The preparation method comprises the following steps: dissolving vanadyl acetylacetonate in methanol, adding a TS-1 type titanium-silicon molecular sieve, and carrying out stirring, dipping, filtering, freeze-drying, roasting and othersteps to obtain the VOX/TS-1 supported catalyst with the vanadium content of 1-5%. According to the invention, the preparation method is simple, the cost is low, and the yield is 100% in terms of vanadium; and by using the vanadium oxide/TS-1 as a catalyst, the catalytic efficiency can be improved while the excessive oxidation of 2,5-dichlorophenol can be effectively inhibited, the excessive oxidation product can be controlled to be 5% or less, the selectivity of 2,5-dichlorophenol can achieve 95% or more, especially the isomer 2,4-dichlorophenol can be significantly inhibited, the selectivity of 2,4-dichlorophenol is less than 0.1%, and the supported catalyst has advantages of easy recovery and reutilization.

The invention discloses a regulating method of oxidized animal oil. Pork is cut into strips, 4%-7% of table salt and 1%-3% of white sugar are uniformly applied to the strips, the strips are pickled at 1-10 DEG C for 48-72 h and then aired at 15-25 DEG C for 6-9 d, subcutaneous fat is taken as a raw material and oxidized with stirring, a reaction is conducted for 1-4 h, 0.05%-0.3% of an antioxidant is added, the reaction is stopped after uniform mixing, cooling is conducted, and the oxidized animal oil is obtained. The method has the advantages of being mild in oxidation condition, easy in oxidation control and convenient to operate and is suitable for industrial production. The obtained oxidized animal oil has the characteristics of being natural and elegant in color, outstanding in characteristic aroma and full in taste, can be used as a precursor to directly participate in preparation of thermal reaction type pork flavors and has great application value and market prospects.

The invention discloses a water-cooled powder preparation device for reducing noise pollution, comprising a roller in which a feeding hole and a powder outlet are formed; the roller is arranged in a first shell; a gap is formed between the first shell and the roller; the gap is filled with heat conductive silicon grease; a grease injection hole is formed in the upper part of the first shell, and a grease discharging hole is formed in the lower part of the first shell; a cooling water pipe is wound on the surface of the first shell; one end of the cooling water pipe is connected to a water cooling machine, and the other end of the cooling water pipe is connected to a water pump; the water outlet end of the water cooling machine communicates with the water feeding end of the water pump through a pipeline; the water-cooled powder preparation device also comprises a second shell surrounding the outer part of the first shell; glass wool is filled between the second shell and the first shell; the front end of the feeding hole is provided with a packing auger; and the powder outlet is internally provided with an exhaust fan. By using the water-cooled powder preparation device, the problems that relatively high noise is generated while the temperature inside a drum of a lead powder machine is continuously raised in the prior art are solved, and the aims of reducing the noise pollution while cooling the lead powder machine are achieved.

The invention relates to a preparation method of a composite material for inhibiting oxidation corrosion by using potassium oleate modified metal sulfide, and belongs to the technical field of surface passivation. The preparation method comprises the following steps of ball-milling pyrite for 5 minutes, sieving with a 100-mesh sieve, washing with ultrapure water (volume: 1: 5) for five times, refrigerating in a refrigerator at-20 DEG C for 12 hours, drying in a freeze dryer for 48 hours, preparing potassium oleate into 5% (volume ratio) by using ultrapure water, putting 1mL and 0.5 g of pyrite samples into a 50mL beaker, shaking the beaker to uniformly spread the samples at the bottom of the beaker, and drying in a fuming cupboard to obtain the composite material. The composite material can be applied to oxidation of surface-passivated pyrite; under the simulated sunlight condition, pyrite oxidation is inhibited in a hydrochloric acid solution with the pH value of 2, and the inhibition rate can reach 80%.