366results about How to "Low purity requirement" patented technology

A hydraulic process for synthesizing the ultrahigh-molecular polyacrylamide used to treat the sewage in oil field includes polymerizing reaction of the acquous solution of acrylamide to become colloid, granulating, proportionally mixing it with solid alkali, and stirring in stirrer while heatinb by the hot water jacket of stirrer. Its molecular weight can reach 28,000,000.

The invention relates to a process for preparing ZrB2-SiC-ZrC complex phase ceramic materials, which is characterized in that purity of zirconium powder is not less than 98%, silicon powder and boron carbide powder are used as raw materials, batching according to reaction equation (2+x)Zr+(1-x)Si+B4C=2ZrB2+(1-x)SiC+ZrC, 0<=x<=0.5 of generating ZrB2-SiC-ZrC, then, materials containing different components are obtained. The raw materials after being ball ground and dried are sintered with heat pressing between 1500-1700DEG C by adjusting sintering technique parameter and employing self-propagating reaction of the raw materials generated in the process of heating up, thereby obtaining the ZrB2-SiC-ZrC complex phase ceramic materials of different components. Relative density of the materials prepared by the invention is larger than 97%, bending strength is 600-900MPa, fracture toughness property is 4.5-6MPa,m1/2, and hardness is 16-19GPa.

The invention relates to a gadolinium-containing sintered neodymium-iron-boron rare earth permanent magnet alloy and a preparation method thereof. The permanent magnet alloy comprises components in the following formula: Re[alpha]Gd[beta]B[gamma]MxNyFe[100-alpha-beta-gamma-x-y], wherein the weight percentage beta of the gadolinium element is more than 0.50 and less than or equal to 25. Through the method for adding the Gd element into a sintered Nd-Fe-B magnet, a sintered Nd-Fe-B permanent magnet with high coercive force and high temperature resistance is prepared. The coercive force temperature coefficient beta of the prepared magnet is reduced, so the coercive force of the magnet at high temperature is improved and the magnet has the high temperature resistance.

The invention discloses an aircraft oil tank inerting device based on a catalytic oxidation technology. High-pressure gas is imported into the device through an engine or an environmental control system, fuel oil steam and mixture other gas in gaseous phase space of the upper portion of an oil tank or fuel oil steam generated by fuel oil electric heater heating in an oil storage tank are/is pumped by two gas ejectors respectively, mixture flammable gas ejected from the gas ejectors is regulated to appropriate temperature through a regenerator, coolers and a gas electric heater then an oxidizing reaction is generated in a catalytic reactor, the fuel oil steam is converted into carbon dioxide and water steam, inert gas which is departed from the water steam is sent to the gaseous phase space of the upper portion of the oil tank or fuel oil of the lower portion of the oil tank, and an inerting aim is achieved. By adopting the technical scheme, the aircraft oil tank inerting device has the advantages that flowing and the mixture of the gas are completed by the gas ejectors, moving parts such as a draught fan are not needed, meanwhile the requirements of dive lowering and air filling increasing can be met, the structure is simple, and the operation is reliable.

The invention discloses an amorphous alloy and a method for preparing the amorphous alloy. The amorphous alloy has a chemical formula of ZraCubAlcMdNe; M is one or more of Ni, Fe, Co, Mn, Cr, Ti, Hf, Ta, Nb and rare-earth element; N is one or more of Ca, Mg and C; a, b, c, d and e represent the atomic percentage respectively, wherein 40<=a<=70, 15<=b<=35, 5<=c<=15, 5<=d<=15 and 0<=e<=2, and a+b+c+d+e=100. Because the amorphous alloy contains the elements of calcium, magnesium and carbon, the used amount of the noble metal is effectively decreased or eliminated, the content of oxygen, nitrogen and other non-metallic elements in the amorphous alloy is effectively inhibited, the critical dimension and the mechanical properties of the amorphous alloys are improved, and hereby the amorphous alloy is more suitable for industrial production and promotion. In addition, due to the addition of the elements of calcium, magnesium and carbon, the requirement for the purity of the raw materials of the amorphous alloy is lowered, and hereby the production cost is reduced.

The present invention relates to propylene producing catalytically cracking process, and is especially propylene producing process with catalytically cracking aluminum silicophosphate. In fixed bed or fluidized bed reactor and at the conditions of temperature 350-550 deg.c, pressure 0.1-0.3 MPa and space velocity 0.1-300 /hr, dry gas, C4 component and other material are cracked in catalyst containing aluminum silicophosphate molecular sieve SAPO-34. The output hydrocarbon mixture is separated to obtain destination product propylene before the other components are returned to the reactor for circular use. The process of the present invention has low reaction temperature, pressure near normal pressure, simple technological process and high propylene selectivity. The present invention can utilizes dry gas and C4 component effectively.

The invention relates to hafnium boride powder with advantages of high purity, good dispersibility, small grain size and narrow distribution range, and a process for synthesizing the powder. The invention is characterized in that the process adopts hafnium oxide, boron carbide, graphite and amorphous boron as raw materials and is based on carbothermic/borothermic reduction reaction, wherein, in the carbothermic reduction, the mass ratio of HfO 2, B4C and C ranges from (1-5/4):(5/7-6/7):(0-3/2); and in the borothermic reduction, the mass ratio of HfO2 and B is 1:(10/3-4). Through adjusting the proportion of the raw materials, controlling the synthesizing process, adopting relatively cheap HfO2 raw material, the invention can synthesize the HfB2 powder with oxygen content less than 0.2wt% under the conditions that the temperature is 1500-1600 DEG C, an Ar atmosphere is adopted, or the vacuum degree is smaller than 1 Pa. SEM and laser grading analysis show that the distribution range of powder grain diameter is narrow (the polydispersity coefficient is 0.005), and the average grain diameter is around 1Mum. All of the parameters are superior to the ordinary commercial HfB2 powder, the preparation process and the required equipment are simple, the cost is low and the yield is high.

The invention discloses a making technique of recrystallizing carborundum product, which comprises the following steps: blending carborundum powder with certain grain grade with purity over 96% and silicon powder and carbon powder evenly; adding a little of adhesive; moulding according to normal technique; placing green compact in the sintering stove; connecting graphite electrode on two ends; filling the composite powder of carborundum powder and carbon powder around two ends; supplying power for graphite electrode; utilizing the conductivity of mould to realize itself heating sintering; insulating 1-4h after the temperature reaches to 1400-1700 deg. c; heating continuously to 2500 deg. c; insulating 3-10h; cooling the stove to indoor temperature naturally; obtaining the high-purity recrystallizing carborundum product.

A zirconium-based amorphous alloy and a preparation method therefor. The composition of the amorphous alloy is ZraCubAlcMd(Er1-xYx)e, wherein M is at least one selected from Ni, Fe, Co, Mn, Cr, Ti, Hf and Ta, 40≤a≤70, 15≤b≤35, 5≤c≤15, 3≤d≤15, 0.2＜e≤2.5, and 0＜x＜0.5, and the amorphous alloy is obtained by smelting and cooling molding under the protection of an inert gas or a vacuum condition.

The invention discloses trehalose synthase of streptomyces griseochromogenes and a coding gene and application of the trehalose synthase. The trehalose synthase gene is cloned from the streptomyces griseochromogenes. The trehalose synthase can convert maltose to generate trehalose, the proper reaction temperature of the trehalose synthase is 15-35 DEG C and is 20-25 DEG C preferably, and the proper pH (potential of hydrogen) of the trehalose synthase ranges from 6.0 to 8.0 and ranges from 7.0 to 7.5 preferably. The conversion efficiency of the trehalose synthase is high, the maltose is used as a substrate, conversion rate of the maltose is about 80% at the reaction temperature of 25 DEG C, and less than 5% of glucose is generated to be beneficial to increase of the conversion rate of the substrate. The trehalose synthase can be used for converting commercial ultrahigh malt syrup to prepare the trehalose, and a novel method using an enzymic method to produce the trehalose industrially can be provided.

The invention belongs to the field of refrigerant, and provides a method for preparing fluorinated alkene by performing dehydrochlorination on chlorofluorocarbon under the action of a catalyst.According to the invention, the novel catalyst is prepared through an impregnation method, reaction of the catalyst and 2-chloro-l, 1, 2-tetrafluoro propane (HCFC-244bb) with lower purity is performed, and then high-temperature gas phase dehydrochlorination reaction is performed to prepare a fluorinated alkene product 2, 3, 3, 3-tetrafluoro propene. Through the adoption of the novel catalyst, the purity requirement on chlorofluoropropane is reduced, so that HCFC-244bb with the purity of 80 percent can be as a raw material, thereby effectively reducing the operating cost of the process; the halohydrocarbon conversion rate is high, and reach up to 60 percent, and the selectivity of the target fluorinated alkene is greater than 90 percent.

The invention provides a preparation method of isocyanate-based polyimide foam. The preparation method comprises that 1, polybasic aromatic anhydride is heated and dissolved in a polar solvent and undergoes a reaction with fatty alcohol to produce a polybasic aromatic anhydride derivative solution, 2, the polybasic aromatic anhydride derivative solution and a foam stabilizer are blended to form a white material, 3, polybasic aromatic anhydride and isocyanate undergo a reaction to produce a black material, 4, the foaming white material is immediately poured into the foaming black material at a room temperature under normal pressure, and the mixture is uniformly stirred, then is fast poured into a mold and is subjected to free foaming molding to form a foam intermediate and 5, the foam intermediate is heated and cured to form the isocyanate-based polyimide foam. The preparation method inhibits production of an amino group and an isocyanate group in foam material preparation, reduces a polyurea generation amount and improves isocyanate-based polyimide foam heat resistance, heat stability and flame resistance. The preparation method has the advantages of simple processes, excellent product comprehensive properties, and industrial production and wide application feasibility.

The invention discloses a method for preparing nano-TiO2 serving as a cathode material of a lithium ion battery. The method comprises the following steps of: beating precipitates of titanium prepared from metatitanic acid or various titanium sources by using water, adding a coordinating agent into thick liquid according to a molar ratio of the coordinating agent to the titanium of 1.0:1-10:1, regulating the pH value to be between 7 and 14 by using alkali, reacting in a stirring reactor at the temperature of between 20 and 80 DEG C for 10 to 720 minutes, and filtering to obtain solution of the titanium; and adding the alkali into the solution according to a molar ratio of the alkali to the titanium of 1.0:1-50:1, heating the solution to between 80 and 200 DEG C for 10 to 600 minutes, filtering and washing to obtain a precursor of nano-TiO2, and calcining the precursor at the temperature of 120 and 850 DEG C for 0.5 to 20 hours to obtain the nano-TiO2 serving as the cathode material of the lithium ion battery. The method has the characteristics of wide range of raw materials, simple process flow, low energy consumption, low cost, good appearance of product granularity and excellent electrochemical properties.

A method for extracting and purifying L-ergothioneine comprises the following steps: (1) soaking and extracting a mushroom mycelium fermentation liquid by using hot water, so as to obtain a mushroom and L-ergothioneine water solution; (2) performing ultrafiltration of the mushroom and L-ergothioneine water solution by using an ultrafiltration membrane with a molecular weight cut-off of 1kDa to 30kDa, and collecting an ultrafiltration liquid; and (3) performing chromatographic purification of the ultrafiltration permeation liquid, the chromatographic purification conditions being: a chromatographic filler being an HILIC filler, a mobile phase forming acetonitrile-water with a volume ratio of 80: 20 to 88: 12, and a quantity of feed of L-ergothioneine being 0.01g to 0.323 per 100g.

A method of producing modified asphalt is characterized in that in a temperature range of from room temperature to 100 DEG C, organic solvent and/or mixed solvent oil capable of dispersing or dissolving coal liquefied heavy products and matrix asphalt are used for mixing the coal liquefied heavy products with the matrix asphalt prior to separation and recycling of the solvent so as to obtain the modified asphalt, wherein the coal liquefied heavy products added account for 5-50% of total percentage of the modified asphalt. The method has the advantage that the production temperature is low, and the modified asphalt has good performances.

The invention relates to a method and equipment for manufacturing an optical fiber perform rod casing pipe with a complicated refractive index profile, and particularly relates to a method and equipment for manufacturing the optical fiber perform rod casing pipe by combination of modified chemical vapor deposition (MCVD) and outside vapor deposition (OVD). The optical fiber perform rod casing pipe manufactured by using the method and the equipment have a deep refractive index sunken zone or the complicated refractive index profile. The equipment comprises a powder casing pipe manufacturing device and a powder casting pipe vitrification device, wherein the powder casing pipe manufacturing device comprises a rotary chuck I, a rotary chuck II, a blow lamp, a sealing rotary joint I, a pressure adjusting valve I and a pressure gauge l, and the powder casting pipe vitrification device comprises a rotary chuck III, a sealing rotary joint II, a sealing cover plate, a fastening bolt, a sealing ring, a furnace body heating zone, a sealing furnace body, an exhaust gas discharge port, a pressure adjusting valve II and a pressure gauge II.

The invention provides a technique for producing cationic polyacrylamide, and comprises the raw materials by mass percent: 10.0 to 25.0% of acrylamide, 5.0 to 10.0% of acryloxyethyl trimethylammonium chloride, 0.02-0.04% of redox, 0.03-0.015% of azo compound, 0.5 to 5.0 of urea, 0.02 to 0.15% of fatty acid salt, and 65.5-84% of deionized water; the raw materials are put into a reactor and added with the redox to have induced polymerization reaction under nitrogen protection at the room temperature, and then added with the azo compound to have secondary induced polymerization reaction; finally, the products of the invention are obtained after granulation and dryness. The technique is stable, slow in induction, even in reaction, mild and ordered, and easy in the control of operation process; the obtained products are rapid in dissolution rate, little in usage, large in water yield, big and dense in floccules, and not easy in fragmentation. The technique is mainly used for various environment-friendly fields such as sewage disposal, sludge dewatering, etc.

The invention discloses a preparation method of a catalyst for the one-step preparation of p-aminophenol from nitrobenzene. The method comprises the following steps: preprocessing active carbon; loading a platinum salt; loading a vanadate; and reducing a catalyst, wherein the mass percentage contents of platinum and vanadium in the catalyst are 0.5-5% and 0.05-0.2% respectively. The invention also discloses a method for the one-step preparation of p-aminophenol from nitrobenzene through utilizing the catalyst. The addition of a certain amount of metallic vanadium to the Pt/C catalyst reduces the poisoning effect of sulfides in the nitrobenzene raw material to platinum, prolongs the service life of the catalyst and also improves the catalysis activity and selectivity of the catalyst; and the prepared catalyst has stable performances and very good repeatability, can be used for catalyzing the one-step preparation of p-aminophenol from nitrobenzene, reduces the purity requirement of the raw material nitrobenzene and reduces the catalysis cost.