1174 results about "Active center" patented technology

The invention discloses a novel mercaptan removal catalyst as well as a preparation method and application thereof, the catalyst takes potassium-containing solution modified activated carbon as a carrier and one or a combination of more of CH3COOCs, CH3COOK, Cs2CO3 and Rb2CO3 as an active component, and the mass ratio of the active component substance to the modified activated carbon is 3-5%. The preparation method comprises the following steps: (1) modifying activated carbon by using a potassium-containing solution with the concentration of 15-20%, soaking the activated carbon for 2-4 hours by using the potassium-containing solution, then cleaning the activated carbon by using deionized water until the pH value is weakly alkaline, and drying the activated carbon for later use; (2) carrying out vacuum drying on the modified activated carbon at a certain temperature, and dipping a certain amount of active component-containing solution at 20-60 DEG C for 4-12 hours; and (3) carrying out vacuum drying on the active carbon impregnated with the active component, and roasting under the protection of N2 to obtain the mercaptan removal catalyst. The preparation method is simple, the prepared mercaptan removal catalyst has the characteristics of large specific surface and pore volume and the like, and compared with existing patents, the mercaptan removal catalyst is more favorable for maintaining the active center of the catalyst, maintaining the activity stability of the catalyst and improving the mercaptan removal rate.

The invention is applicable to the technical field of biological detection, provides a fluorescence immunochromatography detection method based on monatomic nano-enzyme enhancement, and particularly relates to two application forms: in the first form, a detection signal enhanced fluorescence immunochromatography detection card and a sample diluent containing a monatomic nano-enzyme are involved; in the second form, the invention relates to a fluorescence immunochromatography detection card with enhanced detection signals, and a sample pad of the detection card is obtained by soaking a sample pad treatment solution containing a monatomic nano-enzyme solution. The two application forms both relate to a monatomic nano-enzyme solution, and the solution is composed of monatomic nano-enzyme, bio-enzyme composite microspheres, a protective agent, a surfactant, a thickening agent and a preservative. The monatomic nano enzyme is composed of an atomic-scale dispersed metal active center and a carrier material. When the method is used for detecting myocardial and inflammatory markers, the limit of quantitation can reach the pg / mL level, the detection linear range can span three orders of magnitude, and the clinical examination use requirements can be met. The kit can be applied to rapid quantitative detection of myocardial and inflammatory markers, has the advantages of high sensitivity, rapidness, convenience and high efficiency, and provides an auxiliary diagnosis basis for early screening of myocardial infarction, heart failure and infection related diseases.

The invention discloses a carbon nitride-based composite material as well as a preparation method and application thereof. The carbon nitride-based composite material comprises a non-metal doped carbon nitride carrier and a noble metal, wherein the noble metal exists in the carrier in an element doping form and / or is loaded on the carrier in an oxide form; the precious metal is one or more of Pt, Pd, Au and Ru, and the nonmetal is one or more of P, S and I. According to the carbon nitride composite material disclosed by the invention, noble metal is utilized to modify carbon nitride, the number of surface active sites is increased, the electron and chemical structures of an active center are adjusted, and meanwhile, generation and migration of photo-generated charges are promoted. Meanwhile, the surface of the carbon nitride composite material is modified by non-metallic elements, so that adsorption and activation of reactant H2O molecules are effectively promoted. The catalyst disclosed by the invention is simple in preparation process, good in repeatability and easy for large-scale production.

The invention belongs to the technical field of polyfluorosiloxane synthesis, and provides a low-by-product polyfluorosiloxane controllable synthesis method which comprises the following steps: carrying out anionic ring opening polymerization on D3F by adopting a binary organic catalytic system, weakening the strong nucleophilicity of an active center based on hydrogen-bond interaction and steric effect, and inhibiting the occurrence of chain back-biting side reaction, so as to obtain the low-by-product polyfluorosiloxane. The polyfluorosiloxane with low content of by-product DnF (n is greater than or equal to 4), controllable structure and narrow molecular weight distribution is prepared. The polyfluorosiloxane with low byproduct content is catalyzed by the binary organic catalyst, the synthesis method is simple, the operation is convenient, the reaction condition is mild, the catalyst has good stability, large-scale production is easy, and further development of the polyfluorosiloxane in the field of high-end and harsh oil-resistant sealing materials can be promoted.

The invention relates to the technical field of catalysts, in particular to a dehydrogenation catalyst precursor, a dehydrogenation catalyst and a preparation method and application of the dehydrogenation catalyst precursor. According to the dehydrogenation catalyst precursor, a sulfur-modified magnesium-aluminum mixed oxide is used as a carrier, and a Pt metal cluster is used as an active center; wherein the carrier is a mixed-state metal oxide with a layered hydrotalcite structure, a spinel structure and a near-crystalline synergistic structure. A magnesium-aluminum mixed oxide can be prepared by introducing a precursor of alkali metal magnesium into an aluminum oxide precursor, a layered structure or a spinel structure similar to hydrotalcite can be formed by regulating and controlling the calcination temperature, and by combining carrier surface regulation and control modification, the capability of regulating and controlling the interaction between metal and a carrier can be improved, and the performance of the catalyst is improved. Therefore, the active center of the cluster is maintained, and the acid-base property of the surface of the carrier is effectively modulated, so that carbon deposit is reduced, and the activity and stability of the catalyst are improved.

The invention discloses a method for preparing furfuryl amine by reductive amination of biomass-based furfural, which comprises the following steps: adding furfural, a catalyst, ammonia water and a solvent into a closed reaction kettle in proportion, replacing air in the reaction kettle with high-purity hydrogen, and reacting in an oil bath pan for a period of time to obtain a target product furfuryl amine, the nano-catalyst provided by the invention is a nitrogen-doped porous hollow carbon sphere loaded nano bimetallic catalyst, takes noble metal and non-noble metal as a metal active center together, and has adjustability of macroscopic size and microstructure at the same time; the method has the advantages of simple reaction system, mild conditions, no pollution to the environment, high efficiency, energy conservation, low cost, few byproducts, high yield, high selectivity and the like, the furfural is efficiently converted into furfuryl amine at low temperature and low pressure within a short time, the used heterogeneous catalyst is stable and easy to recover, a new thought and direction are provided for enterprise production and scientific research, and the method is suitable for industrial production. The method has great significance on development and utilization of biomass-based furfural.

The invention discloses preparation and application of a manganese hydroxylate modified zirconium-based metal organic framework, and belongs to the technical field of wastewater treatment. According to the preparation method, firstly, Mn oxide serves as a dopant, naphthalic acid serves as a frame connector, a zirconium-manganese bimetal organic frame is prepared through a hydrothermal method, and hydroxylation treatment is conducted through an alkali solution; mn replaces Zr atoms on a zirconium cluster to form high charge density with Zr, Mn and Zr can jointly participate in an electron transfer process and an active oxygen generation process to form double active centers, and the catalytic activity of a Fenton-like system is enhanced, so that the oxidative adsorption removal rate of As is remarkably improved. Experimental results show that the As removal rate can still reach 95.1% after five cycles, the targets of oxidative adsorption of As and reutilization are achieved, and the application of the zirconium-based metal organic framework in the field of catalytic adsorption of As is expanded.

The invention discloses a supported ozone catalyst for printing and dyeing wastewater treatment and a treatment process, and relates to the technical field of wastewater treatment, the supported ozone catalyst comprises an environmental response type porous medium, an active center and a biological enzyme modification layer; the environment-responsive porous medium is based on poly (N-isopropylacrylamide) grafted and modified mesoporous alumina, the initial aperture of the mesoporous alumina is 10-15nm, the grafting rate of poly (N-isopropylacrylamide) is 12-20%, and an active center is composed of a transition metal active center and quantum dots modified on the transition metal active center. The biological enzyme modified layer is obtained by carrying out deep biological modification on the surface of the catalyst by using laccase with oxidation-reduction activity. According to the invention, an environment-responsive porous medium is constructed by grafting mesoporous alumina with poly (N-isopropylacrylamide), so that the problems that a traditional fixed-aperture catalyst is low in mass transfer efficiency and poor in adaptability to working conditions, and the pollutant release efficiency is difficult to effectively improve under different temperature and pH conditions are solved.

The invention discloses an enzyme immobilization method based on charge directed crosslinking, and belongs to the technical field of enzyme immobilization. The method sequentially comprises the following steps: reacting an enzyme with a modifier containing an anionic group to generate an electronegative modified enzyme; dissolving a protonated amino carrier in an acidic buffer solution to form a first solution, and dispersing a dissociation anion group-containing carrier and a modification enzyme in an alkaline buffer solution to form a second solution; mixing the two solutions, and constructing a gel network immobilized enzyme through electrostatic crosslinking; and finally, strengthening the gel network by using a multivalent metal ion solution. Directional anchoring of the enzyme in the gel is achieved through charge matching, the network stability and the enzyme microenvironment are synchronously optimized in combination with metal ion coordination, use of a covalent cross-linking agent is avoided in the whole process, conformation damage of an enzyme active center is avoided, the activity retention rate, the operation half-life period and the substrate mass transfer efficiency of the immobilized enzyme are remarkably improved, and the immobilized enzyme has good application prospects. The method is suitable for efficient immobilization of industrial enzymes such as beta-glucosidase, and has high biocompatibility and industrial potential.

The invention discloses a preparation method and application of a CoNiNOC diatomic electrocatalyst for an electro-Fenton system. The preparation method of the catalyst comprises the following steps: firstly, preparing an oxygen-doped cobalt monatomic catalyst (CoNOC) through a temperature gradient pyrolysis and pickling process, and then preparing an oxygen-doped diatomic catalyst (CoNiNOC) by introducing a Ni site into a precursor and using a similar process. The loading capacity of metal active sites is improved by introducing Ni sites, and the electronic structure of an active center is further regulated and controlled, so that the 2e-ORR activity is improved by 15%, the H2O2 selectivity reaches 96% or above, and the stability is 100 h or above. The invention also discloses an application of the catalyst as a heterogeneous electro-Fenton catalyst in degradation of antibiotics, and a CoNiNOC cathode not only can efficiently degrade TC, but also has higher degradation efficiency, TOC degradation rate and kinetic rate constant for various organic antibiotics.

The invention belongs to the technical field of environmental catalytic materials and pollutant control, and particularly relates to a Ni-coated NiS < 2 >-coated MoS < x > / NF composite catalyst and a preparation method and application thereof. According to the preparation method of the Ni-coated NiS2-coated MoSx / NF composite catalyst provided by the invention, the Ni-coated NiS2-coated MoSx / NF composite catalyst with a self-supported metal / crystalline / amorphous heterojunction is constructed by virtue of a collaborative strategy of directional self-assembly and internal Ni source and water dispersion, and meanwhile, the activation efficiency of peroxymonosulfate (PMS) can be remarkably improved by combining an Ni-Mo bimetal active center, so that the activation efficiency of the Ni-coated NiS2-coated MoSx / NF composite catalyst is improved. The problems that an existing catalyst is limited in active site and poor in structural stability are solved, the excellent capacity of activating PMS to remove antibiotics is shown, therefore, efficient degradation of antibiotic pollutants is achieved, and the catalyst has wide application prospects in antibiotic wastewater treatment.

The invention relates to the technical field of nano materials and biological medicines, in particular to black phosphorus-loaded monatomic nano enzyme as well as a preparation method and application thereof. According to the monatomic nano-enzyme loaded with the black phosphorus, the monatomic nano-enzyme loaded with the black phosphorus takes a black phosphorus nanosheet as a carrier, and a metal simple substance is anchored on the surface of the carrier; wherein the metal elementary substance comprises any one of iron, cobalt and manganese. A metal active center is anchored on a black phosphorus nano-carrier, the catalytic activity of monatomic nano-enzyme and the photo-thermal conversion performance of a black phosphorus nano-material are effectively combined, the anti-tumor effect is jointly enhanced through chemical kinetic catalysis and photo-thermal, in addition, a loaded black phosphorus degradation product is mainly phosphate and has biological safety, and the application prospect is broad. The toxicity problem of the traditional nano-enzyme can be solved; the wide application is facilitated.

The invention belongs to the technical field of biological medicine, and particularly relates to application of anethomycin in preparation of medicine for inhibiting cysteine protease activity. The invention discovers that anethomycin has the function of inhibiting the activity of virus cysteine protease, especially 3C or 3CL protease, for the first time. Molecular docking proves that anethomycin can effectively bind to the catalytic activity center of Senecavirus (SVA) 3C protease. An in-vitro FRET enzyme activity experiment proves that the inhibition rate of 50 [mu] M of anethomycin on SVA 3C protease reaches up to 88.5%. Cellular level experiments show that the anethomycin can significantly inhibit replication of SVA viruses, shows broad-spectrum antiviral activity on various viruses such as encephalomyocarditis viruses (EMCV), porcine reproductive and respiratory syndrome viruses (PRRSV) and porcine deltacoronaviruses (PDCoV), and is low in cytotoxicity and high in selectivity index (SI).

The invention provides an MXene-derived bimetallic composite material as well as a preparation method and application thereof, and relates to the technical field of catalysts. In the MXene-derived bimetallic composite material provided by the invention, a 3D ordered pore structure provides a channel for organic pollutant molecules and H2O2 to transfer mass to a catalytic active center in the material; tiO2 and the MCuFe-MOF generate photo-induced electrons, a TiO2 / Ti3C2Tx Schottky junction and a MCuFe-MOF / Ti3C2Tx Schottky junction promote separation and transfer of charges, and Fe < 3 + > / Fe < 2 + > circulation is accelerated; the synergistic effect of a redox pair between iron and copper in the MCuFe-MOF is shown as a copper-iron bimetal oxide or a copper-iron bimetal organic framework and the like, interface electron transfer can be accelerated, rapid reduction of Fe < 3 + > and Cu < 2 + > is promoted, the Fenton reaction efficiency is improved, and the photo-Fenton catalytic activity is excellent.

The invention discloses a catalyst for directly producing green aromatic hydrocarbon from biomass synthesis gas, and a preparation method and application thereof, and belongs to the field of aromatic hydrocarbon production. The catalyst for directly producing the green aromatic hydrocarbon from the biomass synthesis gas comprises a zeolite molecular sieve and a transition metal modified Fe-based oxide M1M2-FeOx, the mass ratio of the M1M2-FeOx is 10-80%, and the mass ratio of the zeolite molecular sieve is 20-90%; m1 and M2 are transition metals; in the catalyst, transition metal is utilized to modify iron-based metal, so that various CO2 activation sites are formed, and CO2 adsorption activation is promoted; meanwhile, the iron-based metal active center and the zeolite molecular sieve acid center are matched with each other, so that the catalyst can be used in a reaction system for directly preparing the aromatic hydrocarbon from the biomass synthesis gas, and the catalyst has relatively high conversion rate and aromatic hydrocarbon selectivity in preparation of the aromatic hydrocarbon from the carbon dioxide-containing biomass synthesis gas, and has a good industrial application prospect.

The invention belongs to the technical field of organic synthesis and carbene catalysts, and particularly relates to a bridged double-center carbene catalyst ligand as well as a preparation method and application thereof. The structure of the bridged double-center carbene catalyst ligand is as shown in a formula I: # imgabs0 #, in the formula I, R1, R3, R4, R5, R6, R7, R8, R9 and R10 are respectively and independently selected from any one of H, i-Pr, CH3, Cl, F and NC; n is equal to 1-9; n is selected from any one of Cl and Br. Compared with a carbene catalyst ligand used in the past, the bridged double-center carbene catalyst ligand provided by the invention has double active centers, so that the double-center carbene catalyst ligand can be used for preparing the double-active-center carbene catalyst ligand, and the double-active-center carbene catalyst ligand can be used for preparing the double-active-center carbene catalyst ligand; and by carrying out ligand exchange with a carbene catalyst precursor with a single active center, the active center can be aggregated, so that the high-activity carbene catalyst with double centers is obtained, and higher reaction activity and atom economy are achieved.

The invention relates to the technical field of super-hydrophobic materials, and particularly discloses a super-hydrophobic coating spraying liquid, a preparation and construction method thereof and a super-hydrophobic coating. The super-hydrophobic coating spraying liquid provided by the invention is prepared from the following components: nano SiO2 which is modified by a silane coupling agent containing amino / alkoxy and a silane coupling agent containing long fluorine chain / long-chain alkane step by step, microcapsules which are sequentially modified by the silane coupling agent containing amino / alkoxy and a dispersing agent for the second time, and a solvent which is added into the microcapsules, and a thermosetting resin. The nano SiO2 and the microcapsules which are subjected to multiple modification have good hydrophobicity, and nano metal particles loaded in the microcapsules form an anti-algae active center of the super-hydrophobic coating. And the super-hydrophobic coating prepared by using the super-hydrophobic coating spraying liquid organically combines hydrophobicity and an anti-algae active center together, so that an efficient and long-acting anti-algae effect can be realized, and the problems of short pollution flashover prevention time and poor algae removal performance of the existing super-hydrophobic coating are solved.

The invention discloses a magnesium oxide supported catalyst, a preparation method and application in VOCs (volatile organic compounds) purification, and belongs to the field of volatile organic compound catalytic purification. Magnesium oxide is used as a carrier of the catalyst, and two modified materials are supported, one is a double-active-center material anchoring nickel single atoms and ruthenium clusters in a porous carbon-nitrogen framework, and the other is a double-active-center material anchoring nickel single atoms and ruthenium clusters in a porous carbon-nitrogen framework; and the other one is a defective carbonitride MXene intercalated hydroxyapatite nanosheet, and lanthanum oxide can be added as a cocatalyst. The preparation method comprises the following steps: sequentially loading the two modified materials on the magnesium oxide carrier, and carrying out ultrasonic dispersion, stirring, centrifuging, drying, calcining and the like, so that the active component and the carrier form strong interaction. According to the catalyst, through the synergistic effect of double active centers and the structural advantages of the modified material, the catalytic oxidation efficiency and stability of VOCs are remarkably improved, and the catalyst is suitable for purification treatment of industrial waste gas and volatile organic compounds in indoor air.

The invention discloses a nitrogen atom-doped carbon material loaded superfine metal nano-cluster catalyst as well as preparation and application thereof, and belongs to the field of hydrogen production by electrolysis of water. According to the preparation method, UIO-66 (Ce) with the surface rich in mesoporous and microporous structures is prepared by using a soft template and is used as a precursor, and then the precursor is subjected to carbonization and acid pickling treatment to obtain the three-dimensional nitrogen-doped porous carbon spheres with high specific surface area. The rich hierarchical porous structures on the surface of the carbon material can effectively limit the aggregation of metal active centers in high-temperature reduction and HER reaction processes, and the long-term stability of the catalyst is improved. And due to the extremely high specific surface area, more metal active centers can be loaded, so that the catalytic activity is improved. Experiments show that nitrogen doping can effectively regulate and control the electronic structure of an active center, and the catalytic activity and stability of the catalyst are improved.

The invention relates to the technical field of transition metal catalysts, in particular to a transition metal / alkali metal bimetallic monatomic catalyst for catalyzing acetylene hydrochlorination reaction and a preparation method and application of the transition metal / alkali metal bimetallic monatomic catalyst. After dipping in an alkali metal nitrate solution, the alkali metal is firstly converted into a metal oxide through two-stage calcination, and then the metal oxide is converted into a super-strong alkali metal monatomic material containing a high defect site. And dipping the alkali metal monatomic catalyst in a transition metal salt solution to obtain the transition metal / alkali metal bimetallic monatomic catalyst. Transition metal monatomic serves as a main active center, alkali metal monatomic serves as a super alkali auxiliary, the microenvironment of active sites is greatly improved, the adsorption capacity of the transition metal sites to reactants is enhanced, meanwhile, carbon deposition side reaction can be inhibited, and synergistic catalysis between transition metal and alkali metal monatomic is achieved; the catalyst shows high catalytic activity and stability on acetylene hydrochlorination reaction.

The invention discloses a copper-nickel monatomic catalyst based on an MXene carrier and a preparation method and application thereof, and belongs to the technical field of catalysts.The copper-nickel monatomic catalyst comprises the MXene carrier, a copper-nickel monatomic active component is loaded on the MXene carrier, and the MXene carrier is coated with a nitrogen-doped carbon layer; wherein the content of the copper-nickel monatomic active component is 0.2-1.5 wt%, and the molar ratio of copper to nickel in the copper-nickel monatomic active component is (1: 0.3)-(1: 1.2); and the content of the nitrogen-doped carbon coating layer is 7-10 wt%. The copper-nickel monatomic catalyst does not contain toxic chromium metal, an MXene / copper-nickel monatomic / nitrogen-doped carbon layer ternary composite system is adopted, a few-layer MXene carrier provides rich surface active sites, copper-nickel monatomic active components are anchored through chemical adsorption, a dehydrogenation active center of copper atoms and a cyclization active center of nickel atoms have a synergistic effect, and the catalytic activity of the copper-nickel monatomic catalyst is improved. The oxidation resistance and the stability of the catalyst are remarkably improved through coating of the nitrogen-doped carbon layer, the technical bottlenecks of low activity, short service life and heavy pollution of a traditional catalyst are overcome, and an efficient solution is provided for green synthesis of lactone.

Disclosed herein are a catalyst for polyester depolymerization or cyclic ester synthesis, a preparation method therefor and a use thereof. The catalyst is a long-chain catalyst having a main chain carbon atom number greater than or equal to 8, and containing a terminal ion group and a terminal hydroxyl structure; the catalyst may be used to catalyze polyester hydrolysis, alcoholysis or cyclic depolymerization, so as to recover corresponding monomers or monomers and oligomers, or used to catalyze hydroxy acid or hydroxy acid esters to synthesize cyclic ester monomers or cyclic ester monomers and cyclic oligomers by means of polycondensation and cyclization reactions. The catalyst may reduce the viscosity of a reaction system, and may greatly improve the utilization rate of a catalytic active center, reduce the consumption of the catalyst and improve overall catalytic efficiency, achieving high-efficiency, high-yield and selective depolymerization of polyester homopolymers, copolymers, blends or compounds.

A process method for preparing acrylonitrile through propylene ammoxidation belongs to the field of chemical engineering, and is characterized in that in a corresponding device and a reaction system of the method, propylene, ammonia gas and air (in terms of O2) enter a fluidized bed reactor at 400-450 DEG C and 0.01-0.15 MPa for reaction according to a ratio of 1: (1-1.5): (2-10) at a weight hourly space velocity of 0.04-0.1 h <-1 >; the micro-sphere catalyst with the particle size of 40-60 microns in the dense-phase section and the dilute-phase section has alpha-phase bismuth molybdate, gamma-phase bismuth molybdate and lattice oxygen active centers and meets the chemical formula MoaBibNicWdTleVfPgSixOy, the atomic ratio a in the formula is 21-22, the atomic ratio b in the formula is 1.5-2, the atomic ratio c in the formula is 4-5, the atomic ratio d in the formula is 0.8-1, the atomic ratio e in the formula is 0.09-0.1, the atomic ratio f in the formula is 0.15-0.2, the atomic ratio g in the formula is 0.8-1, the atomic ratio x in the formula is 70-71, and y is the number of oxygen atoms needed by the atomic valence of all elements; a product enters a quench tower and a water absorption tower to be neutralized and cooled, and then passes through a recovery tower, an acetonitrile tower, a decyanation tower, a layering device and a finished product tower to realize separation of a water phase and an organic phase, so that crude acetonitrile, hydrocyanic acid and refined acrylonitrile are further obtained. The process is good in conversion degree and product selectivity, stable and reliable in operation, energy-saving and environment-friendly.

The invention relates to the technical field of organic synthetic chemistry, in particular to a preparation method of ethyl 2-n-butyl acetoacetate, which comprises the following specific steps: S1, preparation of a composite solid base catalyst, S2, synthesis of ethyl 2-n-butyl acetoacetate, S3, post-treatment of a reaction solution, and S4, separation and purification of a product. The preparation method has the following beneficial effects that the magnesium-aluminum composite oxide is used as a carrier, and the composite solid base catalyst loaded with potassium and lanthanum has relatively high catalytic activity and selectivity; the magnesium-aluminum composite oxide carrier has a relatively large specific surface area and rich alkaline sites, so that a good catalytic environment is provided for the reaction; as a main active component, potassium ions can effectively activate alpha-active methylene of ethyl acetoacetate and promote formation of negative ion intermediates; the introduction of lanthanum ions can adjust the electronic structure of the catalyst, enhance the stability of the active center and inhibit the occurrence of side reactions.

The invention discloses a composite hydrogen storage material as well as a preparation method and application thereof, and belongs to the technical field of hydrogen storage materials and preparation thereof. The problems that an existing aluminum hydride composite hydrogen storage system is too much in additive dosage, poor in low-temperature kinetics and the like are solved. According to the invention, the rare earth nitride is used as an additive, the multivalent characteristic of the rare earth element is used as an active center, and the nitrogen element has an attraction effect on negative hydrogen, so that the dissociation and transmission of hydrogen are accelerated; the rare earth element can perform electron transmission with aluminum hydride by taking a nitrogen active site as a bridge, so that a synergistic effect between the rare earth element and the aluminum hydride is realized, the affinity of the rare earth element and a hydrogen element is enhanced through an electron donating effect of the nitrogen element, the dehydrogenation temperature of the aluminum hydride material is reduced, and meanwhile, the dehydrogenation kinetics of a low-temperature region of the aluminum hydride material is also improved. In addition, the preparation process of the composite hydrogen storage material is simple and mature, raw materials are cheap and easy to obtain, and large-scale industrial production is facilitated.

The invention discloses a catalyst for preparing cyclohexanone by cyclohexanol dehydrogenation coupled phenol hydrogenation, the catalyst has a composite metal hydrotalcite structure, the metal components comprise ruthenium, magnesium and aluminum, the metal components are uniformly dispersed in hydrotalcite, and the ruthenium, the magnesium and the aluminum respectively account for 1-5wt%, 10-30wt% and 1-10wt% of the total mass of the catalyst. The acid-base property, the specific surface area and the pore structure of the catalyst are optimized by adjusting the ratio of magnesium to aluminum, so that the dispersion of ruthenium is improved, the interaction between ruthenium and a hydrotalcite carrier is increased, and the synergistic effect of all the element components enables active centers in cyclohexanol dehydrogenation, hydrogen transfer and phenol hydrogenation processes to be efficiently combined together, so that the catalytic activity of the catalyst is improved. Rich alkaline sites are generated in the catalyst, the dehydration side reaction of cyclohexanol can be effectively inhibited, meanwhile, the selectivity of cyclohexanone prepared through phenol hydrogenation is improved, it is ensured that the phenol hydrogenation reaction and the cyclohexanol dehydrogenation reaction can be effectively coupled, and cyclohexanone is efficiently prepared.

The invention relates to the technical field of catalysts, and discloses a heavy aromatics lightening catalyst and a preparation method thereof.The preparation method comprises the steps that deionized water, a nickel source and a molybdenum source are added into a container and stirred, then the solution is poured into the container containing a modified molecular sieve, drying, roasting and cooling are conducted after dipping, and the heavy aromatics lightening catalyst is obtained. A large number of carboxyl groups, imino groups and hydroxyl groups are introduced on the surface of the molecular sieve and are subjected to coordination complexation with nickel and molybdenum, and nickel-molybdenum oxide generated by high-temperature calcination can be uniformly distributed in a molecular sieve matrix, has more nickel-molybdenum catalytic active centers, can effectively catalyze C9 < + > heavy aromatics to generate light aromatics BTX, and can be used for preparing the light aromatics BTX. And the catalyst has good practical application in preparation of light aromatic hydrocarbon BTX by catalyzing heavy aromatic hydrocarbon.

The invention discloses a tryptophan synthetase trp B modified gene and a preparation method of 6-fluoro-L-tryptophan, belongs to the technical field of gene modification and amino acid synthesis, and provides a tryptophan synthetase trp B gene subjected to mutation modification, and the nucleotide sequence of the tryptophan synthetase trp B gene is shown as SEQ ID NO.1. After gene modification, substrate molecules can enter the channel more easily. After gene modification, a channel of an active center of tryptophan synthetase is more beneficial to entering of substrates 6-fluoroindole and L-serine, and the yield of 6-fluoro-L-tryptophan is increased. According to the method, a specific strain containing tryptophan synthetase is adopted, tryptophan synthetase can be efficiently expressed by culturing in an optimized culture medium, so that the 6-fluoro-L-tryptophan synthesized by an enzymic method has relatively high catalytic rate and conversion rate, the molar conversion rate of L-serine reaches 86.5% or above, the reaction conditions of the enzymic method synthesis are mild, the enzyme stereoselectivity is strong, the catalytic efficiency is high, and the method is suitable for industrial production. The method is suitable for industrial production.

The invention provides an angiotensin converting enzyme inhibitory peptide and application thereof. The amino acid sequence of the angiotensin converting enzyme inhibitory peptide is PVKP. The ACE inhibitory activity of the inhibitory peptide PVKP provided by the invention is obviously improved compared with that of the original inhibitory peptide LYPVK, and the IC50 value is reduced from 10.6 mu g / mL to 9.6 mu g / mL; the digestive enzyme stability of the inhibitory peptide PVKP provided by the invention and the digestive enzyme stability of the original inhibitory peptide LYPVK under the same concentration are improved. Molecular simulation docking verifies that the interaction force between the ACE inhibitory peptide PVKP and ACE is enhanced compared with that of an original inhibitory peptide LYPVK, and the interaction force between alkyl groups and the interaction between the alkyl groups and Zn < 2 + > of an ACE active center are increased. The intracellular antihypertensive activity of the ACE inhibitory peptide PVKP is further verified through cell experiments, and compared with the original inhibitory peptide LYPVK, the intracellular NO release content is increased, and the ET-1 content is reduced. The ACE inhibitory peptide PVKP is small in molecular weight and good in water solubility, and application of the ACE inhibitory peptide PVKP in development of products with the blood pressure lowering effect is facilitated.

The invention relates to the technical field of intermetallic compound catalysts, and particularly discloses a preparation method of a hexagonal layered Pt-Bi intermetallic compound nanocrystalline catalyst, which comprises the following steps: weighing octadecene and oleylamine, and mixing to obtain a solution A; platinum acetylacetonate, bismuth acetate, ascorbic acid and hexadecyl trimethyl ammonium bromide are weighed and sequentially poured into the solution A, and a solution B is obtained through mixing and ultrasonic treatment; heating and preserving heat of the solution B, and naturally cooling to room temperature to obtain a turbid liquid C; and measuring cyclohexane and ethanol, sequentially pouring into the turbid liquid C, carrying out ultrasonic treatment at room temperature for 3 minutes, then pouring out supernate, repeating for 2-3 times, collecting a product, and drying to obtain the nanocrystalline catalyst. According to the invention, the electron interaction between bimetallic components is utilized, the electron structure of a catalytic active center is optimized, the interaction between the active structure and reaction active species is enhanced, the evolution kinetics of a plurality of reaction intermediates such as * O and * OOH in the electrocatalytic oxygen reduction reaction can be obviously accelerated, and the kinetics rate of the four-electron oxygen reduction reaction is improved.