5290 results about "High activity" patented technology

Embodiments described herein relate generally to apparatuses and processes for forming semi-solid electrodes having high active solids loading by removing excess electrolyte. In some embodiments, the semi-solid electrode material can be formed by mixing an active material and, optionally, a conductive material in a liquid electrolyte to form a suspension. In some embodiments, the semi-solid electrode material can be disposed onto a current collector to form an intermediate electrode. In some embodiments, the semi-solid electrode material can have a first composition in which the ratio of electrolyte to active material is between about 10:1 and about 1:1. In some embodiments, a method for converting the semi-solid electrode material from the first composition into the second composition includes removing a portion of the electrolyte from the semi-solid electrode material. In some embodiments, the method includes mechanically compressing the intermediate electrode to remove the portion of electrolyte from the semi-solid electrode material.

The invention relates to a high-activity recombinant XVII type collagen as well as a rapid preparation method and application thereof, and belongs to the technical field of bioengineering. The amino acid sequence of the high-activity recombinant XVII type collagen is as shown in SEQ ID NO. 1, and the nucleotide sequence of the high-activity recombinant XVII type collagen is as shown in SEQ ID NO. 2. The invention also provides a preparation method and application of the recombinant XVII type collagen. The high-activity recombinant XVII type collagen has good biological activity, has good effects of promoting cell adhesion, cell proliferation and cell migration, and can be compounded with other proteins to form raw materials of tissue engineering products, cosmetics, health care products or medicines. The high-activity recombinant XVII type collagen gene is integrated to different positions of a yeast genome through three different vectors, and the copy number of a target gene is increased, so that the expression quantity of the recombinant XVII type collagen is remarkably increased, and the yield of the high-activity recombinant XVII type collagen is effectively increased.

The invention belongs to the technical field of building materials, and discloses a high-activity composite auxiliary cementing material based on carbonated steel slag-carbide slag as well as a preparation method and application of the high-activity composite auxiliary cementing material. The high-activity composite auxiliary cementing material is prepared from the following raw materials in parts by mass: 40 to 55 parts of carbonated steel slag-carbide slag composite micro powder, 30 to 40 parts of high titanium slag, 20 to 25 parts of metakaolin, 3 to 5 parts of ardealite, 3 to 5 parts of calcium carbonate, 3 to 5 parts of calcium carbonate and 3 to 5 parts of calcium carbonate. Wherein the carbonated steel slag-carbide slag composite micro powder is obtained by carrying out carbon sequestration reaction on steel slag and carbide slag in a solution consisting of a carbonization enhancer, an additive and water. On one hand, the CO2 storage amount of the steel slag and the carbide slag is increased, the stability and the activity are improved, on the other hand, the carbonized steel slag-carbide slag and other industrial solid waste are cooperated to achieve a composite superimposed effect, the cement mortar or the concrete can be improved in strength, stability and durability, the comprehensive performance is good, and the cost is low. And the method is green, low-carbon, energy-saving, environment-friendly and wide in popularization and application

The invention relates to the technical field of processing and utilization of microorganisms and mineral resources, in particular to a rare earth extracting agent and application thereof. The rare earth extracting agent provided by the invention comprises silicon-decomposing microorganisms, acid-producing microorganisms or fermentation products thereof which are screened from rare earth mines and rare earth wastes and have good symbiotic effect, high compatibility and high activity, so that the silicon-decomposing and acid-producing efficiency is further improved, and the rare earth element extracting efficiency is high. The rare earth leaching agent provided by the invention is simple and safe in component, and solves the problems of large chemical reagent dosage, high production cost, serious environmental pollution and the like in the rare earth waste chemical leaching process. The method is suitable for popularization.

The invention provides anti-cracking and anti-seepage high-performance concrete, which relates to the technical field of concrete and comprises Portland cement, aggregate, a high-activity mineral admixture, a calcium-magnesium composite expanding agent, nano silicon dioxide particles, a microcapsule-packaged sodium silicate and calcium lactate solution, paraffin / expanded graphite composite phase change microspheres, steel fibers, PVA fibers and nano cellulose. The self-repairing concrete has the characteristics that the anti-cracking performance is comprehensively improved, the anti-seepage grade is broken through, the self-repairing capability is long-acting, the construction adaptability is enhanced, and the like.

The invention provides a carbonyl reductase mutant. The carbonyl reductase mutant is obtained by performing single-point mutation or multi-point combined mutation on the 17th site, the 40th site and the 64th site of an amino acid sequence as shown in SEQ ID NO.1. The invention also provides a coding gene, a recombinant vector containing the coding gene, a co-expression engineering bacterium and an application of the co-expression engineering bacterium. Compared with a wild type enzyme, the carbonyl reductase mutant has high activity and high stereoselectivity, the enzyme activity can reach more than two times that of the wild type enzyme, the catalytic efficiency on a substrate precursor ketone is remarkably improved, the yield of a statin drug intermediate and chiral alcohol synthesized by an enzyme method of the carbonyl reductase mutant is remarkably improved, and the yield of a rosuvastatin intermediate (3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R, 3R) is remarkably improved. The highest yields of the (3R, 5R)-6-chloro-3, 5-dihydroxyhexanoic acid tert-butyl ester and the atorvastatin intermediate (3R, 5R)-6-cyano-3, 5-dihydroxyhexanoic acid tert-butyl ester reach 99% and 97.6% respectively, e.e. Is larger than 99%, and the method has high industrial application value.

The invention relates to a recombinant A type humanized XVII type collagen as well as construction and application thereof, the protein is the humanized XVII type collagen which is composed of an intracellular region, a transmembrane region and an extracellular region, and the amino acid sequence is as shown in SEQ No. 1. The hair follicle repairing agent has the advantages of hair follicle repairing, hair regeneration, good biological activities of cell proliferation, cell adhesion and the like, and can be widely applied to the fields of medicines, medical instruments, biological materials, tissue engineering, cosmetics and the like. The gene sequence of the recombinant A type XVII collagen is 100% identical to the corresponding part of the gene sequence of the recombinant A type XVII collagen, so that the recombinant A type XVII collagen has good hydrophilicity and high activity, and has application potential in the fields of biomedical materials, beauty cosmetics, skin care products and the like.

The present invention relates to a recombinant yeast with high squalene production, a construction method and a use thereof, wherein the recombinant yeast is a saccharomyces cerevisiae that expresses or overexpresses HMGR gene, ADA gene, LEU2 gene, MVA pathway gene and squalene synthase gene ERG9. The present invention integrates acetaldehyde dehydrogenase gene ADA and HMG-CoA reductase gene tHMGR in multiple copies in saccharomyces cerevisiae, integrates the screened high-activity phosphoketolase gene PK and phosphotransacetylase gene PTA, weakens epoxysqualene synthesis, strengthens the mevalonate pathway, overexpresses yeast endogenous squalene synthase gene, etc. to obtain a recombinant yeast with high squalene production, so that the production in the shake flask stage of the production process exceeds 5g / L, and the production in the fed batch fermentation stage exceeds 50g / L, breaking through the current bottleneck of microbial synthesis of squalene production, and is suitable for practical promotion and application.

The present invention belongs to the technical field of cosmetic raw materials, and specifically relates to a kind of oxidized hyaluronic acid-PDRN-peptide nanoemulsion and its preparation method. The nanoemulsion comprises oxidized hyaluronic acid, PDRN and polypeptide, and the nanoemulsion is formed by oxidized hyaluronic acid, PDRN and polypeptide through layer-by-layer self-assembly technology. Specifically: positively charged polypeptide is used to wrap negatively charged PDRN to form positively charged composite particles, or negatively charged PDRN is used to wrap positively charged polypeptide to form electrostatic composite particles, and then, the positively charged composite particles or the electrostatic composite particles are further wrapped with oxidized hyaluronic acid as a packaging material, and finally oxidized hyaluronic acid-PDRN-peptide nanoemulsion is formed. The nanoemulsion of the present invention can improve the stability of polypeptides, improve the problems that polypeptide molecules are difficult to penetrate the skin and have low bioavailability, and effectively improve the transdermal rate and stability of PDRN, give play to the tissue repair function of PDRN, further amplify the anti-inflammatory effects of the two, and improve the bioavailability of active ingredients.

The invention discloses a high-strength and high-toughness aluminum nitride ceramic and a preparation method thereof, and relates to the technical field of ceramics, a sol-gel method is adopted to coat the surface of aluminum nitride with a stable shell layer to form a core-shell structure, meanwhile, the low lattice mismatch rate of a core-shell interface is utilized to reduce thermal resistance, and toughness and thermal conductivity are both considered; according to the external magnetic field tape casting method, the magnetic dipole moment orientation principle is utilized, an external magnetic field is applied in the tape casting stage, the in-plane mechanical property is improved, and the fracture toughness is improved through the magnetism of aluminum nitride whiskers; a reinforcement is introduced to improve the mechanical property and corrosion resistance of the aluminum nitride ceramic material, multi-granularity powder is compounded, large-particle aluminum nitride powder is used as a sintering and heat-conducting framework material, and high activity provided by submicron particles is utilized to promote sintering, so that the sintering temperature of aluminum nitride can be remarkably reduced, and the performance is greatly improved; and the aluminum nitride substrate expands more application fields on a future packaging circuit.

The invention discloses a high-activity and high-thermal-stability MHET hydrolase mutant and application thereof. The invention provides a mutant protein of thermophilic carboxylesterase, which is shown as 1) or 2): 1) the protein shown as 1) is a protein obtained by mutating amino acid residues at the 130th site and the 171th site of wild thermophilic carboxylesterase shown as SEQ ID NO.2 or a sequence corresponding to the SEQ ID NO.2 and keeping other amino acid residues unchanged; (2) the protein is obtained by mutating amino acid residues at the 127th site, the 130th site and the 171th site of wild thermophilic carboxylesterase and keeping other amino acid residues unchanged. Experiments prove that the activity of the modified mutant for catalyzing MHET hydrolysis at the temperature of 50 DEG C is improved by 95 times compared with that of a wild type, and the modified mutant has higher enzyme activity and thermal stability and is the first enzyme capable of efficiently catalyzing MHET hydrolysis at the temperature of 50 DEG C at present.

The invention discloses a preparation method of a metal-based nano-enzyme and application of the metal-based nano-enzyme in treatment of periodontitis, the nano-enzyme combines two metal bases, and the nano-enzyme exerts anti-inflammatory, vascularization and osteogenesis effects through advantage complementation to treat periodontitis. The nano-enzyme for treating periodontitis has excellent anti-oxidation / anti-inflammatory performance, exerts an ROS elimination function in a specific environment, responds to a periodontitis pathology microenvironment to release metal ions, exerts a growth factor-like function of the metal ions and realizes repair of blood vessels and bone tissues. The multifunctional nano material has the advantages of simple process, low cost, high activity and the like, and has a good treatment effect on periodontitis.

The invention relates to the technical field of program control, and discloses a high-activity selenium yeast intelligent production control system based on gradient feeding monitoring. The system comprises a data acquisition module, a control parameter acquisition module, a gradient calculation module, an intelligent control module and a material supplementing control module. The system collects process production data, extracts key control parameters and weights, calculates real-time gradient values of the parameters, forms six-dimensional gradient vectors, generates control gradient indexes in combination with the parameter weights and time sequence attenuation weights, and then forms an addition control decision. And according to the decision and the process state dynamic data, the material supplementing opportunity is identified, an active adding instruction is generated, programmed control and adjustment of the raw materials and the additives are achieved, and the control precision and the production automation level are improved.

The invention belongs to the technical field of calcium hydroxide preparation, and particularly relates to a preparation method of calcium hydroxide with high specific surface area, which comprises the following steps: S1, adding triethanolamine and diethanolisopropanolamine into water, and uniformly mixing to obtain an active agent solution; s2, mixing quick lime with an active agent solution, and carrying out digestion reaction to generate a calcium hydroxide coarse material; and S3, sieving and drying the calcium hydroxide coarse material to obtain the calcium hydroxide with the high specific surface area. The specific surface area of calcium hydroxide can be remarkably increased through the active agent solution, meanwhile, the uniformity and sufficiency of the quick lime digestion reaction are optimized, the calcium hydroxide particle aggregation phenomenon is reduced, and finally the calcium hydroxide product with the high specific surface area and the high activity is prepared.

The invention discloses a peptide with a bone strengthening effect as well as a preparation method and application thereof, and relates to the field of biology. The casein is used as a raw material, the high-activity calcium ion chelating peptide and the directional preparation technology thereof are provided, the technology has the advantages of being high in efficiency, low in cost, easy to operate, good in stability and the like, the high-activity calcium ion chelating peptide can be prepared on a large scale, the utilization value of the casein is improved, and a new way is provided for development of functional natural calcium supplement products.

The invention relates to the technical field of fuel cells, and provides a preparation method of a fuel cell carbon-supported platinum catalyst, the catalyst and application, the preparation method comprises the following steps: S1, adding a platinum precursor solution and a carbon material into a solvent, dispersing, drying and grinding to obtain catalyst powder A; s2, performing primary microwave treatment on the catalyst powder A under inert gas to obtain catalyst powder B; and S3, mixing and grinding the catalyst powder B and the platinum precursor solid, and carrying out secondary microwave treatment under inert gas to obtain the carbon-supported platinum catalyst. The preparation method has the advantages that through two-step microwave treatment, the particle size of the platinum particles inside and outside the pores of the carbon carrier is accurately controlled under the condition that the high activity of the platinum particles is kept, so that the carbon-supported platinum catalyst has the advantages of high performance, high stability and durability, and meanwhile, the performance of the catalyst is not influenced under the low-humidity working condition.

The invention provides a negative electrode material and a preparation method thereof. The negative electrode material comprises an inner core and a coating layer coating the surface of the inner core, the inner core comprises a porous carbon matrix and amorphous nano silicon particles dispersed in the porous carbon matrix; pores in the porous carbon matrix comprise micropores, the pore diameter of the micropores is less than 2nm, and the quantity of the micropores accounts for more than or equal to 80% of the total quantity of the pores. According to the negative electrode material, a silicon-carbon material core is coated with a coating layer, and the number of micropores in a porous carbon matrix is adjusted, so that on one hand, direct contact reaction between high-activity nano silicon and an electrolyte is effectively avoided; and on the other hand, the particle size of the amorphous nano silicon particles in the negative electrode material is relatively small, the dispersity in the porous carbon matrix is relatively good, and the negative electrode material has relatively low expansion rate and relatively high initial coulombic efficiency, rate capability and cycle performance.

The invention discloses a rare-earth metal arylamine group compound as well as preparation method and application thereof. The invention discloses the rare-earth metal arylamine group compound which is characterized in that a general formula of the rare-earth metal arylamine group compound is (2,6-R12PhNH)5LnLi2(THF)2, wherein Ln is a rear-earth metal selected from one of neodymium, samarium, ytterbium or yttrium; R1 is selected from one of hydrogen, methyl or isopropyl. The rare-earth metal arylamine group compound has the advantages that the rare-earth metal arylamine group compound has a definite structure; raw materials used in the preparation method are simple, easily obtained and cheap; the reaction process is simple and easily operated; the rare-earth metal arylamine group compound product is conveniently purified and the yield of the product is high; the rare-earth metal arylamine group compound has a high activity when acting as a single component catalyst to catalyze a hydrogen phosphine reaction of aldehyde or ketone and phosphite ester; the use amount of the catalyst is less; the yield is high; a substrate has wide universality; a new and simple method is provided for synthesis of a-hydroxyphosphonate.

The invention discloses a highly active graphite felt for vanadium battery and a preparation method thereof, and belongs to the technical field of all-vanadium liquid flow battery electrodes. The method comprises the following steps: electrodepositing a layer of polymer on the graphite felt, then hydrothermally loading metal molybdenum, chelating the metal molybdenum with phytic acid, and finally pyrolyzing at high temperature to obtain a graphite felt loaded with an organic skeleton-metal oxide-organic skeleton hierarchical structure. The hierarchical structure is not only conducive to increasing the specific surface area and active sites of the graphite felt, but also can protect the metal catalyst from falling off or being consumed under long-term catalytic reaction and electrolyte flushing.

The invention discloses a streptomyces-derived cytochrome P450 enzyme mutant and an application of the streptomyces-derived cytochrome P450 enzyme mutant in synthesis of ursodesoxycholic acid. The cytochrome P450 enzyme mutant is obtained by carrying out single mutation or multiple mutation on the 181st site, the 192nd site, the 249th site or the 288th site of an amino acid sequence shown in SEQ ID NO.2. The cytochrome P450 enzyme mutant has high activity and regioselectivity, low-cost lithocholic acid is used as a substrate, efficient cytochrome P450 enzyme is used for hydroxylating the 7beta site of the lithocholic acid, ursodesoxycholic acid is synthesized in one step, the industrial production cost is greatly reduced, and the cytochrome P450 enzyme mutant has good application prospects in industrial production of ursodesoxycholic acid.

The invention belongs to the technical field of electrocatalytic oxidation, and particularly relates to an electrocatalytic active anode film capable of efficiently producing active chlorine and a preparation method and application of the electrocatalytic active anode film. Porous foam titanium is used as a base material, a surface oxidation layer is removed through acidification pretreatment, a titanium dioxide nanotube array grows on the base material in situ through two times of anodic oxidation to serve as a middle layer, and the binding force of the catalyst and the substrate is effectively improved; meanwhile, Ti < 4 + > in TiO2 is partially converted into Ti < 3 + > through a cathode reduction method, so that the conductivity of the material can be enhanced; furthermore, a RuO2 catalytic layer capable of reducing the chlorine evolution potential is loaded on the titanium dioxide nanotube array, so that the electrocatalytic activity is improved. The prepared anode film has a porous structure, and when the anode film is applied to a Flow-through system, the yield of active chlorine and the contact oxidation efficiency of pollutants on an interface of the anode film are improved, and the problem of mass transfer limitation is solved. The electrocatalytic active anode film can realize high-efficiency decoloration of printing and dyeing wastewater under the conditions of no addition of chemicals and low energy consumption.

The invention belongs to the technical field of high polymer materials, and particularly relates to a preparation method of active end group polyarylether sulfone. The preparation method of the active end group polyarylether sulfone comprises the following steps: mixing a dihalogenated aromatic sulfone monomer, an alkaline reagent and an aprotic polar solvent, adding an aromatic dihydroxyl monomer in batches for polymerization reaction, and desalting to obtain a polyarylether sulfone system; the temperature of the polymerization reaction is 120 to 240 DEG C; the number of times of adding the aromatic dihydroxyl monomer to carry out the polymerization reaction is more than three; and mixing the polyarylether sulfone system with an end-capping reagent, and carrying out an end-capping reaction to obtain the polyarylether sulfone. According to the preparation method of the polyarylether sulfone provided by the invention, through fine synthesis of step-by-step polymerization, reaction temperature control, effective control of reaction rate and inhibition of hydrolysis rate of raw materials, the obtained polyarylether sulfone is high in purity, proper in active end group content and good in solution color and luster, and has a better toughening effect when being combined with epoxy resin.

The invention discloses a preparation method of a high-activity hierarchical pore boric acid imprinted hydrogel microsphere adsorbent and application of the adsorbent to selective adsorption of a flavonoid compound naringin NRG. According to the invention, dopamine is used for modifying COFs so as to enhance surface functionalization of COFs; preparing a sulfydryl functionalized covalent organic framework microsphere; synthesizing sulfydryl microspheres by utilizing an emulsion interfacial polymerization method; preparing a COFs boron affinity imprinting microsphere adsorbent based on boron affinity interaction; the adsorbent is applied to selective adsorption of NRG in agricultural wastewater. The prepared adsorbent has a remarkable multilayer adsorption effect, and the adsorption capacity is remarkably improved through the boron affinity effect. The multi-stage pore structure of the COFs microspheres provides abundant sites for adsorption, and the mass transfer rate is remarkably improved. In addition, the prepared adsorbent shows remarkable specificity in the aspects of adsorption and separation of NRG, and a promising adsorption material is provided for industrial separation of NRG.

The invention provides a machine learning optimization method and system for a low-temperature high-activity CO2 methanation catalyst, and relates to the technical field of machine learning. The optimization method comprises the following steps: collecting CO2 methanation reaction data, building a machine learning model for hyper-parameter optimization, selecting an optimal model, carrying out interpretable analysis on the optimal model, and screening the catalyst by combining the optimal model with a multi-objective optimization algorithm, so that the machine learning optimization of the CO2 methanation catalyst is realized, and the machine learning can analyze a large amount of data so as to realize the optimization of the CO2 methanation catalyst. The catalyst with high activity and selectivity is rapidly predicted and screened out, and the research and development efficiency is greatly improved; machine learning can reduce experiment times, optimize experiment design, significantly reduce research and development cost, and improve research and development success rate; machine learning can identify and utilize complex chemical and physical data, a catalyst with better performance is designed in a high-precision manner, and the conversion rate and selectivity of converting CO2 into CH4 are improved.

The invention discloses high-stability immobilized candida antarctica lipase B as well as a preparation method and application thereof, and belongs to the technical field of enzyme engineering and biological catalysis. The preparation method comprises the following steps: modifying resin by adopting a silane coupling agent to obtain silanized resin; carrying out aldehyde functional modification on the silanized resin by using dialdehyde cellulose to obtain alkyl-aldehyde modified resin; candida antarctica lipase B is immobilized by using alkyl-aldehyde modified resin, and after the Candida antarctica lipase B is subjected to interfacial activation on the surface of the alkyl-aldehyde modified resin, the Candida antarctica lipase B is covalently bound with aldehyde on the surface of the alkyl-aldehyde modified resin; the prepared immobilized Candida antarctica lipase B has relatively high activity and stability. The method is simple to operate, the prepared immobilized lipase is high in stability, and the method can be used for preparing the high-stability immobilized lipase on a large scale and has the potential of industrial popularization and application.

The invention belongs to the field of enzymatic preparation of structural phospholipids, and particularly relates to a method for preparing phosphatidylserine through interfacial enzyme catalysis. A series of high-activity immobilized phospholipase are prepared by innovatively adopting bifunctional group modified hollow mesoporous silica microspheres as a carrier and adsorbing immobilized phospholipase D. The catalyst has the functions of a catalyst and an emulsifier, and a Pickering emulsion interfacial enzyme catalysis system can be efficiently constructed. In the system, the phosphatidylcholine and the serine are efficiently converted into the phosphatidylserine through a phosphatidyl transfer reaction, the conversion rate of the phosphatidylserine within 20 minutes can reach 85%-95%, and the catalytic efficiency reaches up to 372 mmol / (g.h). In addition, after the catalyst is recycled for 10 times, the conversion rate is still kept at 70.9%, and the catalyst shows excellent stability and reusability. The method has the remarkable advantages of being mild in reaction condition, high in catalytic efficiency, capable of being repeatedly used and the like, and a new technical approach is provided for industrial production of phosphatidylserine.

The invention provides a supported IrOx catalyst as well as a preparation method and application thereof. The supported IrOx catalyst comprises an oxide carrier and an active component supported on the carrier, the active component comprises an Ir elementary substance and amorphous IrOx coated on the surface of the Ir elementary substance; and the crystal structure of the IrOx is long-range disordered and short-range ordered. The preparation method of the supported IrOx catalyst is convenient to implement, high in reproducibility and beneficial to industrial preparation and production, gram-level batch preparation can be achieved under the laboratory condition, and possibility is provided for large-scale preparation of the low-cost, high-activity and high-stability proton exchange membrane water electrolysis hydrogen production anode catalyst.

The invention discloses a preparation method and application of a novel protonated layered iridium oxide H-IrO2 nanosheet, the iridium oxide nanosheet has a typical layered structure, a large number of protons are accommodated between layers of the layered structure, and the surface of the layered structure has the characteristics of rich metal iridium vacancy defects and local disorder. The preparation method comprises the following steps: 1) performing alkaline hydrolysis on iridium metal salt to obtain an amorphous iridium oxide precursor; 2) performing Joule heating treatment to obtain a layered iridium oxide nanosheet structure, and 3) performing acid proton exchange to obtain the protonated layered iridium oxide nanosheet. The novel layered structure shows high activity and excellent stability in catalysis of an acidic electrolyzed water anode oxygen evolution reaction, and due to the unique structure and excellent performance of the novel layered structure, the novel layered structure is expected to replace an existing commercial catalyst and plays a key role in a large-scale water electrolysis process.

The invention discloses a high-activity short-cut nitrification quick-start long-term stable operation process, which relates to the technical field of biological sewage treatment, and comprises the following steps: inoculating sludge, carrying out anaerobic fermentation pretreatment, and removing expanded sludge and sludge foam in combination with quick sludge discharge and manual removal; controlling the number of days of sludge age, reproliferating the sludge, enriching ammonia oxidizing bacteria, and inhibiting and elutriating nitrite oxidizing bacteria; long-term operation is carried out under the condition of no sludge discharge, the abundance and activity of ammonia oxidizing bacteria are maintained, and meanwhile, the abundance of nitrite oxidizing bacteria is controlled; the proliferation of nitrite oxidizing bacteria is controlled by using the predation effect of protozoa and metazoan, and the accumulation rate of nitrite in the reactor is controlled; monitoring the dissolved oxygen, the pH value and the concentrations of ammonia nitrogen, nitrite nitrogen and nitrate nitrogen in the reactor in real time, and regulating and controlling the influent ammonia nitrogen load and the free ammonia concentration; dissolved oxygen distribution is adjusted in an intermittent aeration or microporous aeration mode, and the operation conditions of the short-cut nitrification reactor are optimized. The method is simple to operate, economical and effective.