519results about How to "Improve conversion rate" patented technology

The invention discloses a catalyst used for preparing acrylic acid and butyl ester by the dehydration of butyl lactate and a preparation method thereof. The catalyst is a composite catalyst, comprising a main catalyst A and auxiliary catalysts B, C, D and E, wherein, A is calcium sulphate, B is sulphuric acid, C is phosphate, D is alkaline matter and E is promoter. The preparation method comprises the steps as follows: five compositions A, B, C, D and E are sufficiently mixed, baked for 2-10 hours at the temperature of 200-800DEG C and formed for standby. The catalyst has high catalytic activation; under the catalysis of the catalyst, the molar yield reaches 75.1 percent and the molar selectivity of the acrylic acid and butyl ester reaches 71.5 percent. The preparation method has the advantages that the crystal structure of the main catalyst can be improved so as to be beneficial for carrying out the reaction; and the introduction of different auxiliary catalysts and quantities is helpful to improve the conversion ratio of the raw material and the product selectivity and is beneficial for improving the strength of the catalyst.

The invention discloses a synthetic method of a water soluble ultraviolet light absorber BP-9. The method mainly comprises the following process steps: (1) carrying out methylation on the main raw materials of 2, 2', 4, 4'-tetrahydroxyl benzophenone, a transition metal salt catalyst and a mixed solvent which is prepared from dichloroethane and anhydrous ethanol in equal parts by weight to obtain 2, 2'-dihydroxyl-4, 4'-dimethoxyl benzophenone; (2) carrying out sulfonation reaction on the main raw materials of methylate, sulfamic acid and C1-C3 halohydrocarbon to obtain 2, 2'-dihydroxyl-4, 4'-dimethoxyl benzophenone-5, 5'-disulfonic acid; and (3) carrying out neutral reaction on the main raw materials of sulfonated product, inorganic base and ethanol water to finally obtain the BP-9 product. The synthetic method disclosed by the invention is few in reaction step, low in cost, high in product purity and stable in quality, and raw materials are easily available.

The invention discloses a cross-platform content generation and distribution method based on a multi-modal AI, and belongs to the technical field of cross-platform content generation and distribution, and the method comprises the steps: carrying out the content analysis and feature extraction of an original material based on a multi-modal AI model, and generating a structured content label and a semantic vector. By combining a vector matching degree formula of target portrait features and platform features, an adaptation strategy is dynamically generated, it is ensured that content not only conforms to platform rules, but also can accurately reach a target group, the conversion rate and user viscosity are finally improved, visual, text and semantic vectors are aligned through a Transform multi-modal fusion model, a cross-modal joint representation vector is generated, and the user experience is improved. And in combination with an adversarial generative network, differentiated variants of the same theme are generated in batches, and a content diversity score mechanism ensures that generated contents are balanced between creativity and compliance.

The invention discloses high-purity oxamide with concentrated particle size and spherical morphology, a preparation method of the high-purity oxamide and application of the high-purity oxamide in preparation of a slow-release fertilizer, and belongs to the technical field of oxamide synthesis and application. The method comprises the following steps: mixing an ammonia-alcohol solution and an alcohol ester solution, conveying the mixed solution into a series tubular reactor for reaction, and then conveying the mixed solution into a parallel tubular reactor for reaction after pressure stabilization and flow equalization to obtain a reaction solution containing oxamide; performing flash evaporation on the reaction liquid to obtain flash evaporation liquid and flash evaporation gas, and performing solid-liquid separation on the flash evaporation liquid to obtain solid oxamide and filtrate; and drying the solid oxamide to obtain the oxamide. The method realizes high conversion rate and high purity, and the product has ultrafine particle size distribution. The purity of the prepared oxamide is greater than or equal to 99%, the D50 particle size is concentrated to 50 + / -15 microns, the spherical morphology is uniform, the release is stable, and the oxamide has a very good effect in preparation of long-acting slow-release fertilizers and combustion inhibitors and research on the nitrogen utilization rate.

The invention discloses a catechol side group-containing polylysine derivative as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) dissolving catechol acid in an organic phase, firstly adding NHS, stirring and dissolving until the materials are uniformly mixed, then adding EDC.HCl, and stirring and reacting to obtain a catechol-NHS intermediate solution; (2) dissolving polylysine or a salt thereof in a water phase, and adjusting the pH value to 6.0-7.0 by using an alkaline solution to obtain a solution of polylysine or a salt thereof; and (3) adding the intermediate solution obtained in the step (1) into the polylysine or the salt solution thereof obtained in the step (2), and maintaining the pH value of the reaction system at 5.0-6.0 by using an alkaline solution to obtain the catechol side group-containing polylysine derivative. The preparation method is short in reaction time and mild in reaction condition, and the obtained product is high in grafting rate and high in raw material conversion rate and has a good application prospect in the aspects of tissue adhesives and the like.

The invention belongs to the technical field of organic synthesis, and particularly relates to a catalyst-free continuous production method of chlorotert-butane, which comprises the following steps: adding diluted hydrochloric acid as a starting solution into the tower kettle of a reactive distillation tower, and heating the tower kettle to boil until reflux exists at the tower top; the method comprises the following steps: adding tert-butyl alcohol and concentrated hydrochloric acid into a mixing preheater for preheating, then continuously feeding from a feed port of a reactive distillation tower until the tower top temperature is 45-48 DEG C, the side discharge port temperature is 50-52 DEG C and the tower kettle temperature is 96-105 DEG C, and carrying out reflux according to a reflux ratio of (1.5-3): 1; and continuously extracting crude chlorinated tert-butane from a side discharge port of the tower, cooling, neutralizing, drying and filtering to obtain the chlorinated tert-butane. According to the invention, through the integrated design of the mixing preheater and the reactive distillation column, especially by utilizing the reactive distillation technology to continuously remove the product, the chemical equilibrium limitation of the traditional intermittent process is successfully broken, the raw material conversion rate is obviously improved, and meanwhile, the green production targets of flow simplification, energy consumption reduction and three-waste emission reduction are realized.

The invention relates to the technical field of bioengineering, in particular to a penicillin G acylase mutant, polynucleotide, an expression vector and application. The penicillin G acylase mutant is obtained by carrying out site-directed mutagenesis on a wild type penicillin G acylase gene of parent Escherichia coli, and carrying out site-directed mutagenesis on the wild type penicillin G acylase gene to obtain the penicillin G acylase mutant. Phenylalanine (F) at the 24th site of an alpha chain, proline (P) at the 383rd site of a beta chain, threonine (T) at the 384th site of the beta chain, glutamic acid (G) at the 385th site of the beta chain and serine (S) at the 386th site of the beta chain of the penicillin G acylase are introduced and mutated by a whole plasmid PCR (Polymerase Chain Reaction) technology to obtain mutants. When the penicillin G acylase mutant obtained by the invention is used for catalyzing methyl mandelate and 3-(1-methyl-1H-tetrazole-5-yl) thiomethyl-7-aminocephalosporanic acid to synthesize cefamandole, the synthesis activity is improved, and meanwhile, the side reaction rate is greatly reduced.

The invention discloses an esterification reaction lipase screening method based on covalent bond docking, and belongs to the technical field of protein docking simulation. According to the method, parameters of an acylase intermediate are constructed, and then covalent docking and energy screening are performed on the acylase intermediate, so that prediction of lipase reaction activity and substrate selectivity is realized, and the defects that carbonyl carbon cannot be automatically identified, Ser-C covalent bonds cannot be established, double bonds / bond angles cannot be managed, and the reaction efficiency is low in traditional docking are overcome. The problems that in a covalent system, simulation of a nucleophilic attack path lacks a unified distance, angle and dihedral angle constraint system, and automatic and high-throughput screening of multiple lipases and multiple substrates is difficult to achieve are solved.

The invention belongs to the technical field of synthesis of 2, 3-dipicolinic acid, and relates to a catalyst for synthesizing 2, 3-dipicolinic acid as well as a preparation method and application thereof, the catalyst is prepared from a carrier, and active components and auxiliaries loaded on the carrier; the carrier is boron nitride modified aluminum oxide, the active component is palladium-cobalt bimetal, and the auxiliary agent is magnesium; the catalyst comprises the following components in percentage by mass: 0.2 wt%-3wt% of palladium, 0.5 wt%-4wt% of cobalt, 0.05 wt%-0.3 wt% of magnesium, 5wt%-15wt% of boron nitride and the balance of an aluminum oxide carrier. The catalyst is prepared by adopting an ultrasonic-assisted sol-gel method, so that high dispersion and strong interaction of active components are realized. The catalyst shows high catalytic activity, high selectivity and excellent stability in a dichloropyridine carbonylation reaction, carbon monoxide is used as a carbonyl source, the atom economy is high, and the green chemical requirement is met.

The invention discloses a preparation method of an arfamarana key intermediate, which comprises the following steps: carrying out nucleophilic addition reaction on a compound I and 1-[3-chloro-5-(trifluoromethyl) phenyl]-2, 2, 2-trifluoroethanone under the action of an organic solvent A and alkali to obtain a compound II; dissolving the compound II in an organic solvent B, adding concentrated sulfuric acid, carrying out intramolecular dehydration and cyanogen hydrolysis, and after the reaction is finished, cooling to room temperature for crystal growing to obtain a compound III; dissolving the compound III in an organic solvent C, carrying out intramolecular cyclization and ester hydrolysis reaction on the compound III and hydroxylamine hydrochloride under the action of a certain amount of sodium hydroxide aqueous solution, and after the reaction is finished, collecting a water phase and adjusting the pH value of the water phase, so as to obtain the key intermediate of arfampanaga. The reaction in each step has a high conversion rate, the purity of the prepared arfamarin intermediate is high, and powerful support and guarantee are provided for preparation of high-purity arfamarin.

The application discloses a nitrogen-doped carbon-coated three-metal catalyst and a preparation method and application thereof, and belongs to the field of catalyst preparation and application. The method adopts sucrose, melamine and metal salt as low-cost raw materials, and forms an alkaline environment with the assistance of sodium hydroxide. In the environment, melamine is hydrolyzed into cyanuric acid, which is complexed with sucrose metal ions to form a stable supramolecular aggregate precursor containing metal, and then realizes effective encapsulation of the metal in a high-temperature pyrolysis process. The synergistic effect of the three metal elements Co, Ni and Zn significantly improves the performance of the catalyst, so that CoNiZnO@NC-600 not only exhibits high conversion rate (98.4%) and selectivity (99%) in the reaction of hydrogenation conversion of furfural to furfuryl alcohol, but also has excellent cycle stability, thereby providing a new efficient method for the hydrogenation conversion of biomass-derived compounds.

The application provides a method for dynamically regulating alcohol content to enhance the flavor of solid vinegar, comprising the following steps: S1, liquefaction; S2, saccharification; S3, alcohol fermentation; S4, solid-state layered fermentation; and S5, finished product preparation. The vinegar preparation method has the advantages that the fermentation performance is improved, the fermentation period is shortened, the conversion rate of acetic acid is improved, the biomass of bacteria is increased, the growth of acetic acid bacteria is as good as possible, the rate of acetic acid fermentation is improved, the period of acetic acid fermentation is shortened, the flavor of liquid-state fermented vinegar is improved, the irritation of solid-state fermented vinegar is reduced, and the method has a good market application prospect.

The invention relates to the technical field of catalysts, and discloses a catalyst and a preparation method thereof, and a method for preparing 4-methyl-1-pentene through propylene dimerization, the catalyst comprises a carrier, and an active metal component and an auxiliary metal component loaded on the carrier; wherein the carrier comprises potassium carbonate and a binder, the active metal component is selected from sodium and / or potassium, and the auxiliary metal component is selected from at least one of precious metals; wherein on the basis of the mass of the carrier, the content of the active metal component is 1-20wt% and the content of the auxiliary metal component is 0.1-10wt% in terms of metal elements. The catalyst has high catalytic activity and stability in propylene dimerization reaction.

The present invention relates to a copper oxide powder having a specific surface area of at least 25.0 m 2 / g to 70.0 m 2 / g, a crystallite size of not more than 150.0 Angstrom (A), and a chlorine content of less than 200 ppm, and a process for the production of the copper oxide powder.

The present invention relates to an air purification catalyst composition comprising porous manganese oxide, wherein the porous manganese oxide has a pore distribution such that pores having a pore size in the range of 0 nm to 6.0 nm account for at least 75% by volume of the total pores. The invention also relates to an air purification article comprising the air purification catalyst composition, as well as a method for producing the air purification article and a method for purifying an air stream.

The present application relates to a kind of methods for catalytically converting methane to olefins, aromatics and hydrogen in joule heat coupled metal catalytic reactor.The methane feed gas heated by hot joule heat is passed into metal catalytic reactor for catalytic conversion reaction to prepare olefins, aromatics and hydrogen using joule heat as heat source.The conversion rate of methane is 35-85%;The selectivity of olefins is 65-90%;The selectivity of aromatics is 13-40%;Zero carbon deposition.The present application has the characteristics of electric heating conversion efficiency > 90%, long catalyst life, high methane conversion rate and product selectivity, zero carbon deposition, catalyst does not need to be enlarged, small industrialization difficulty, good process repeatability, safe and reliable operation, etc., and has broad industrial application prospect.

The invention relates to a method for preparing high-purity germanium through reduction of hydrogen and germanium tetrachloride, and belongs to the technical field of high-purity metal material preparation. The method comprises the following steps: introducing vaporized germanium tetrachloride and preheated hydrogen from the top of a vertical quartz reaction tube, and mixing; the mixed gas downwards passes through a reaction zone, a concentric quartz ring tube bundle is arranged in the reaction zone, and the reaction zone is divided into an upper high-temperature reaction zone (1000-1150 DEG C), a middle medium-temperature deposition zone (600-850 DEG C) and a lower high-temperature melting zone (940-1000 DEG C) in the gas flow direction; gaseous germanium is condensed in the ring tube bundle in the middle deposition area to form solid germanium, and the solid germanium grows downwards to the lower melting area to be melted into liquid to drop and be collected; and treating the tail gas to recover germanium tetrachloride and hydrogen for recycling. Through the design of the annular tube bundle carrier and the temperature field, the deposition-melting dynamic process is achieved, reaction balance is broken, and the conversion per pass of germanium tetrachloride is increased to 70% or above.

The invention relates to the technical field of propylene dimerization catalysts, and discloses a propylene dimerization catalyst, a preparation method thereof and a method for preparing 4-methyl-1-pentene through propylene dimerization, the preparation method comprises the following steps: (1) mixing alkali carbonate, graphite fluoride, methylcellulose and potassium stearate, and carrying out molding and molding roasting to obtain a carrier; wherein the mass ratio of the alkali carbonate to the graphite fluoride to the methyl cellulose to the potassium stearate is 100: (0.5-5): (0.1-20): (0.1-30); (2) loading an active metal on the carrier; wherein the active metal is selected from sodium and / or potassium. The catalyst prepared by the preparation method has high propylene conversion per pass and high 4M1P selectivity.

The invention relates to a display device and a personalized recommendation reason generation method. The display apparatus includes: a display configured to display a user interface; an audio output device configured to output sound; the controller is configured to display a search result page in response to a multimedia content search operation triggered by a target user; in the process that the target user carries out multimedia content search for the search result page, target multimedia content is selected; a personalized recommendation reason of the target multimedia content is obtained, and the personalized recommendation reason is generated based on the user portrait data of the target user and the media asset data of the target multimedia content; and controlling at least one of the display and the audio output device, and displaying the personalized recommendation reason. By adopting the display equipment, the conversion rate of a multimedia content search function can be improved.

The application discloses a method for preparing adipic acid by coupling hydrogen production through electro-catalytic oxidation of cyclohexanol / cyclohexanone. The H-shaped electrolytic tank is used for catalytic oxidation; the working electrode of the anode chamber and the cathode chamber and the reference electrode jointly form an electro-catalytic reactor; the reaction raw material liquid is a water solution of cyclohexanol / cyclohexanone and electrolyte, and the anode is oxidized into adipic acid and hydrogen is generated in the cathode under a certain working voltage and current density after reaction for a period of time. Compared with the traditional process, the application has the advantages of high efficiency, high selectivity, green, low cost, simple operation and the like, is suitable for industrial implementation, and has a wide application prospect.

The application belongs to the field of biopharmacy and bioconversion, and particularly relates to a lipase mutant and application thereof. The lipase CALB mutant of the application is obtained by adopting single-point mutation or combined mutation on positions 40, 134, 154, 189, 278 and 281 of the amino acid sequence shown in SEQ ID NO. 1. The mutant greatly improves the stereoselectivity in catalyzing the production of (S)-3-cyclohexene-1-methyl formate from racemic 3-cyclohexene-1-methyl formate. Compared with the traditional chemical method for preparing (S)-3-cyclohexene-1-methyl formate, the lipase CALB mutant provided by the application has high stereoselectivity, mild reaction conditions, is friendly to the environment, has reduced requirements on equipment, greatly reduces the production cost, and shows a wide application prospect in industrial application.

The invention provides a preparation method of fluorodinitrile. The preparation method comprises the following steps: reacting trifluoromethanesulfonic anhydride with fluoroalkyl alcohol to obtain fluoroalkyl substituted trifluoromethanesulfonate; then, the fluoroalkyl substituted trifluoromethanesulfonate reacts with malononitrile, and fluorodinitrile is obtained; the reaction raw materials used in the method are easy to obtain and low in price, the target product conversion rate is high, byproducts are few, the purity of the prepared fluorodinitrile is as high as 99%, the yield is higher than 84%, the content of chloride and bromide ions is lower than 5 ppm, and the fluorodinitrile can meet the requirement of serving as an electrolyte additive.

The present application relates to the production field of organic chemical raw material cyclohexene, and discloses a production method of cyclohexene.The method comprises the following steps: carrying out cracking reaction on cyclohexylbenzene and / or dicyclohexylbenzene raw material and a solid acid catalyst to obtain cyclohexene and benzene; and the solid acid catalyst is selected from at least one of amorphous silicon aluminum, molecular sieve and solid supported inorganic acid.The method has the advantages of high raw material conversion rate, high cyclohexene yield and no by-product cyclohexane, etc.

A system and method for separating aluminum trichloride from cold-hydrogenated silicon tetrachloride includes a pressure-reducing tank, a condenser, a first extraction tank, a second extraction tank, a clear liquid filter, and a clear liquid tank. The system is characterized by: a silicon tetrachloride inlet pipe at the top of the pressure-reducing tank; the bottom of the pressure-reducing tank being connected to the first and second extraction tanks via pipes; the bottoms of the first and second extraction tanks being connected to a dryer via pipes; the side walls of the first and second extraction tanks being connected to the clear liquid filter via pipes; the tops of the first and second extraction tanks being connected to the condenser via pipes; the bottom of the condenser having a liquid outlet pipe connected to the top of the clear liquid tank; and the bottom of the clear liquid tank having a silicon tetrachloride recovery pipe; and the clear liquid filter being connected to the liquid outlet pipe via a pipe. This invention improves the clogging situation of the entire cold hydrogenation system, solves the problem of long-term operation of the cold hydrogenation system, and reduces the equipment failure rate.

The application discloses a preparation method of medium and long chain fatty acid triglyceride, and belongs to the technical field of oil deep processing. Firstly, plant oil and medium chain fatty acid triglyceride are used as substrates, a low eutectic solvent is used as a reaction medium, and an ester exchange reaction is carried out under the catalysis of immobilized lipase; after the reaction is completed, centrifugal treatment is carried out, and the low eutectic solvent, the immobilized lipase and the reaction product are recovered respectively; the recovered low eutectic solvent and the immobilized lipase are used for the next batch of reaction, and the recovered upper oil phase is the reaction product. The application uses immobilized lipase to catalyze ester exchange to prepare medium and long chain fatty acid triglyceride in a low eutectic system, the substrate conversion rate and the product generation amount are high, the product separation is easy, further separation and purification are not needed, the low eutectic solvent is green, environment-friendly and reusable, and the method has good ecological, economic benefits and industrialization application prospects.

The application discloses a preparation method of a palladium-iron-based catalyst. A carbon carrier is added into an iron precursor solution, and after impregnation, solid-liquid separation, washing, drying and calcination in an oxygen-containing atmosphere, an iron and carbon mixed carrier is obtained. Then the mixed carrier is impregnated in a palladium precursor solution, and after separation, washing and drying, the palladium-iron-based catalyst is obtained after reduction. The palladium-iron-based catalyst prepared by the method has high dispersion and stable palladium. In the reaction of selective hydrogenation of phenol to cyclohexanone, the conversion rate of phenol and the yield of cyclohexanone are both higher than 95%, and the catalyst has good catalytic stability.

The method for catalytically preparing D-mannose provided in the application can effectively reduce the amount of by-products glucose and fructose, and greatly improve the conversion rate of D-mannose. Specifically, the engineering bacteria expressing isoamylase gene and the engineering bacteria expressing alpha-glucan phosphorylase gene, glucose phosphomutase gene, bifunctional enzyme glucose phosphate isomerase / mannose 6-phosphate isomerase gene and mannose 6-phosphate phosphatase gene are used, starch or starch derivatives are used as substrates, phosphate buffer solution and Mg 2+ A preliminary catalytic system is constructed, and after the reaction is completed, there are unreacted substrates and maltodextrin in the reaction system, the saccharifying enzyme can hydrolyze the unreacted substrates and maltodextrin into glucose, the polyphosphate glucose kinase can convert all the glucose into phosphorylated glucose with the assistance of sodium hexametaphosphate, and then D-mannose is generated, thereby improving the yield and removing the by-products in the system.

This invention belongs to the field of chemical catalyst preparation technology, and discloses a catalyst for the disproportionation of diethylamine to triethylamine. The catalyst includes a support, and MgO, ZnO, and rare earth oxides supported on the support. The content of each component, based on 100% mass, is as follows: support 80-85%, MgO 5-10%, ZnO 5-10%, and rare earth metal oxides 2-5%. When used for the disproportionation of diethylamine to triethylamine, the catalyst exhibits high diethylamine conversion and high selectivity for the triethylamine product. After separation, unreacted diethylamine can be recycled, while monoethylamine is collected separately or recycled back to the diethylamine synthesis unit, significantly reducing overall costs.

The application discloses a fluid kinetic energy capturing device based on a vortex cylinder and a flexible wake slapping plate, wherein the vortex cylinder energy collection system is used for generating vortex-induced vibration response under the action of fluid to collect fluid kinetic energy; the flexible wake slapping energy collection system is arranged at the rear of the vortex cylinder energy collection system in the flow direction; when the vortex cylinder energy collection system cannot be excited out of the resonance lock-in frequency area, the flexible wake slapping energy collection system is used for capturing fluid kinetic energy under the action of the unsteady flow vortex environment shed at the rear of the vortex cylinder energy collection system; when the vortex cylinder energy collection system generates vortex-induced vibration response under the action of fluid, the flexible wake slapping energy collection system is used for assisting in capturing fluid kinetic energy. The energy collection mode of the application is suitable for a wide range of working flow rates, not only improves the working ability out of the resonance lock-in frequency area, but also improves the fluid energy conversion rate in a composite manner, has strong energy collection robustness, high energy conversion rate, is green and environment-friendly, and is suitable for underwater environment.