91results about How to "Increase synthesis rate" patented technology

The invention is a kind of lithium ion cell positive material, which concretely refers to a manufacturing method for a kind of lithium manganic acid material which has an even spinel structure. The invention uses high purity electrolyzation MnO2 or/and chemical MnO2 as materials, the MnO2 with multi-aperture skeleton can be acquired through baking in 500-1000oC, acid processed for 0.5-3 hours in 70-100 oC, the block beforehand mixture; then they are synthesized for 8-30 hours in air under temperature of 700-900 oC, the product can acquired after being cooled and grinded. The material has a large capacity, the electrochemical performance is stable, and the cost is low, especially applicable to the lithium ion cell.

The invention discloses a method for producing glucosamine through fermentation of escherichia coli. After the escherichia coli, bacillus subtilis and staphylococcus are subjected to seed activation,a mixed fermentation agent is prepared, the mixed fermentation agent is inoculated into a fermentation medium containing glucose and a nitrogen source for constant-temperature shaking table culture, the fermentation process is carried out in a constant-speed material supplementing mode, the fermentation pH is controlled to be 6.8-7.0 through ammonia water, thus fermentation liquid containing the glucosamine is obtained, and the glucosamine is obtained after separation and purification. The fermentation activity of the escherichia coli is improved through the mixed fermentation agent, through addition of cysteine and alanine, the production speed of glutamic acid in the fermentation process can be decreased, and the synthesis rate of the glucosamine is increased.

The invention discloses a method for synthesizing and preparing high-quality methyl salicylate. An original concentrated-sulfuric-acid catalyst is replaced with a new catalyst. The new catalyst is prepared from base materials, polysaccharide, sulfide, talcum powder and addition agent, wherein base materials are prepared in the mode that silicon dioxide, kieselguhr and aluminum oxide are stirred and mixed; polysaccharide is one or more of poly-N-acetylglucosamine, galactose and polyfructosan; sulfide is one or two of potassium hydrogen sulfate and copper sulfate; addition agent is one or two of polyving akohol and polysorbitol. The new catalyst is stable in quality, even in concentration, steady in preparing-process operation, low in preparing cost, small in toxicity, good in repeatability, easy to operate and suitable for industrial mass production; meanwhile, the method replaces the traditional methyl salicylate synthesizing and preparing method with concentrated sulfuric acid as the catalyst, and the catalytic effect is obvious; meanwhile, the synthetic speed of the methyl salicylate is increased, and reaction time is shortened.

The invention belongs to the technical field of high-voltage ceramic dielectric capacitor materials, and provides a lead-free high-voltage medium-temperature sintered strontium bismuth titanium-baseddielectric material and a preparation method thereof. The strontium bismuth titanium-based dielectric material is prepared from the following raw materials: SrCO3, TiO2, Bi2O3 and a metal oxide. The strontium bismuth titanium-based dielectric material can meet the requirements of a high-voltage ceramic capacitor and a negative temperature compensation type capacitor on the dielectric property of the material at the same time, and is wider in application range; and medium-temperature sintering can be realized only by adding a common sintering aid without synthesizing cooling glass in advance oradding low-melting-point oxides such as lithium and boron. The preparation method comprises the following steps: firstly, pre-synthesizing a sintered block by adopting a solid-phase synthesis method,then preparing materials for the second time, ball-milling, drying, preparing a sample, and sintering at a medium temperature in an air atmosphere. The preparation method is simple in production andpreparation process and suitable for industrial production.

The invention discloses a fermentation method for producing N-acetylneuraminic acid and relates to the technical field of N-acetylneuraminic acid production. The fermentation method for producing N-acetylneuraminic acid comprises the steps of adding supplementary feed liquid to a fermentation culture medium inoculated with N-acetyl-neuraminic acid bacteria during fermentation, wherein the feed liquid contains glycerin and an additive, the additive is selected from one or more of N-acetylglucosamine and polyphosphoric acid substances. The fermentation method improves the synthesis rate of N-acetylneuraminic acid and meanwhile improves the yield of the N-acetylneuraminic acid by optimizing the composition or use amount of the feed liquid.

The invention discloses a polycarboxylate water reducer composition for self-compaction high-workability concrete. The polycarboxylate water reducer composition is composed of the following components: allyl alcohol polyoxyethylene ether, an unsaturated acid, functional monomers, an oxidizing agent, a reducing agent and a chain transfer agent, wherein the unsaturated acid consists of citric acid,acetic anhydride, acrylic acid and methacrylic acid according to a mass ratio of (1-3):(1-2):(2-3):(5-10), and the functional monomers are nano-diatomaceous earth and sulfonated melamine formaldehyderesin. According to the invention, the water reducer is synthesized by the allyl alcohol polyoxyethylene ether and the unsaturated acid, so that mixing performance of concrete can be improved, meanwhile, steel bars can be prevented from rusting, and the service life of the concrete is prolonged. Mutual reactions between cementing materials can be promoted through the functional monomers, and workability of the concrete is enhanced.

The invention discloses a method for synthesizing ammonia through high-temperature electrolysis by taking low-concentration gas as fuel, which comprises the following steps: preparing a proton conductor solid oxide electrolytic tank consisting of a porous Ni-BZCY cathode, a BZCY electrolyte and a porous LSCF-BZCY anode; preparing a low-concentration gas component as a fuel, and preparing humid air as an anode gas; and introducing fuel into a cathode gas channel of a solid oxide electrolytic tank, introducing humid air into an anode gas channel of the solid oxide electrolytic tank, and carrying out ammonia synthesis reaction on protons and nitrogen in low-concentration gas at 700 DEG C through external voltage. The comprehensive utilization rate of the low-concentration gas can be increased, the product ammonia gas can directly or indirectly reduce carbon emission and hydrogen production energy consumption in the synthesis ammonia industry, carbon circulation in the fossil fuel synthesis ammonia industry can be achieved, and energy conservation and emission reduction of the whole synthesis ammonia system are promoted.

The invention discloses a highly-efficient preparation method for a strong-fluorescence graphene quantum dot. The highly-efficient preparation method comprises the following steps: with pyrene as a reactant precursor and concentrated nitric acid as a nitrating agent, mixing the pyrene with the concentrated nitric acid in proportion, subjecting a mixed solution to water-bath heating to a constant low temperature of 60 to 80 DEG C under a reflux state, and carrying out a nitration reaction so as to obtain an intermediate product namely 1,3,6-trinitropyrene; and dissolving the intermediate product and an alkaline substance namely hydrazine hydrate into a solvent in a certain proportion, carrying out ultrasonic crushing so as to obtain an ultrasonically-crushed suspension, then transferring the suspension to a high-pressure-resistant reaction kettle, carrying out a hydrothermal reaction so as to synthesize a graphene quantum dot solution with high quantum efficiency, and carrying out vacuum filtering, drying and collection so as to obtain a graphene quantum dot powder. The method provided by the invention has the advantages of simple and highly-efficient preparation process, low cost,high quantum efficiency, environmental protection, no generation of harmful wastes and convenience in large-scale production, and facilitates promotion of graphene quantum dot application.

The invention provides a device for facilitating control of a substrate temperature in diamond synthesis equipment. The device comprises a substrate table and a substrate, the top of the substrate table is provided with a plurality of first heat conducting rods, the substrate is supported on the substrate table by the first heat conducting rods, and the cross sections of the first heat conductingrods are of polygonal structures. By arranging a plurality of the first heat conducting rods between the substrate table and the substrate for supporting, a worker can change the thermal conductivitybetween the substrate table and the substrate by changing the number of the first heat conducting rods, thereby achieving reasonable control of the heat dissipation capability of the substrate, sincethe cross sections of the first heat conducting rods are of the polygonal structures, no relative sliding occurs between the substrate table and the substrate, so that the thermal conductivity betweenthe substrate table and the substrate is away stable after the first heat conducting rods are well placed, and the control effect of the heat dissipation capability of the substrate is more reproducible. The device is applied to the field of the diamond synthesis equipment.

The invention provides a super-large plasmid construction kit, a super-large plasmid construction method and application of the super-large plasmid construction kit. The kit comprises a DNA fragment Fn to be assembled and a vector, wherein the vector includes an intermediate vector and/or an assembly vector. The kit further comprises a lambda bacteriophage Red recombination system. By adopting a mode of combining in-vitro assembly and in-vivo assembly, large-fragment DNA and the assembly vector are firstly assembled in vitro by adopting a recombinase system, and then the in-vitro assembly product and the lambda phage Red recombinant system are simultaneously transformed into escherichia coli for in-vivo assembly. The constructed kit combines the advantages of in-vitro assembly and in-vivoassembly, the in-vivo assembly capacity of escherichia coli is enhanced by adopting the lambda phage Red recombination system, the synthesis rate of super-large plasmids is increased, and the synthesis success rate of the super-large plasmids is remarkably increased.