3052 results about "Imine" patented technology

The invention relates to the technical field of environmental materials and water treatment, in particular to a graphene amino silica gel composite adsorbent for heavy metal wastewater treatment and a preparation method thereof.The graphene amino silica gel composite adsorbent is prepared from # imgabs0 nanoparticles, an amino-functionalized silicon dioxide coating layer, carboxylated reduced graphene oxide, a polydopamine modification layer and tetraethyl orthosilicate; the coating is prepared from the following raw materials: 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, N-((4-vinyl benzyl) amino) diacetic acid, chitosan, beta-cyclodextrin, hexadecyl trimethyl ammonium bromide, polyethylene glycol, L-ascorbic acid, 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide. The composite adsorbent shows excellent adsorption performance on various heavy metal ions, and the adsorption performance is far higher than that of traditional adsorption materials and existing composite adsorbents.

The invention discloses an environment-friendly slow release fertilizer and a preparation method thereof, and belongs to the technical field of fertilizer mixture preparation. The preparation method comprises the following steps: mixing and stirring a mussel extract-polysaccharide-nitrogen fertilizer complex, an inorganic fertilizer and water according to a weight part ratio of (1-2): (5-7): (15-23), heating to 50-60 DEG C to form a dispersion solution, mixing and stirring the dispersion solution and a calcium salt according to a weight part ratio of 1: (0.005-0.01), cooling to 20-25 DEG C, and reacting for 20-24 hours to obtain a viscous mixture; and drying, dewatering and crushing the viscous mixture to obtain the environment-friendly slow-release fertilizer. According to the environment-friendly slow-release fertilizer, the mussel extract with a good adhesion effect and the carboxymethyl cellulose or the hyaluronic acid with biocompatibility are used as carriers, through the synergistic cooperation of an amide structure, an imine structure and metal coordination, wrapping of a nitrogen fertilizer and an inorganic fertilizer is achieved, and finally the environment-friendly slow-release fertilizer is obtained.

The invention relates to the technical field of automobile tires, and discloses a new energy automobile tire self-repairing sealing material adhered with mute cotton. The preparation method comprises the following steps: adding a modified polyurethane adhesive, C5 petroleum resin and a modified carbon nanotube filler into absolute ethyl alcohol, mixing to obtain a self-repairing liquid, adhering polyurethane cotton to the upper part of the self-repairing liquid, and drying to obtain the new energy automobile tire self-repairing sealing material adhered with the mute cotton. Disulfide bonds, boric acid ester bonds and imine bonds introduced into polyurethane through a chain extension reaction and diselenide bonds introduced into carbon nanotubes all belong to dynamic covalent bonds, so that the self-repairing performance of the material is improved; by introducing a rigid benzene ring and naphthyl aromatic structure, the mechanical property of the self-repairing sealing material is improved; the carbon nano tube can play a role in skeleton supporting in a polyurethane matrix, and the mechanical property of the material is further improved by introducing an adamantane rigid structure into the carbon nano tube.

The invention discloses a temperature / CO2 dual-response zwitterionic hydrogel profile control agent, which is prepared by taking a monomer A, a monomer B and a monomer C as raw materials, adding a cross-linking agent and an initiator, and carrying out polymerization reaction in a water medium. The monomer A is selected from any one of acrylamide, acrylic acid and 1-vinyl-2-pyrrolidone; the monomer B is selected from any one of [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide, 2-methacryloyloxyethyl phosphorylcholine and 3-((2-(methacryloyloxy) ethyl) dimethylamino) propionic acid inner salt; and the monomer C is selected from any one of 2-(dimethylamino) ethyl methacrylate, dimethylamino propyl methacrylamide and polyethyleneimine. The profile control agent has double swelling mechanisms, has outstanding temperature and salt resistance, resists 220000 mg / L of mineralization water, is suitable for high-salt reservoirs, and is good in long-term aging property.

The invention relates to a preparation method of a nanofiltration membrane containing a covalent organic framework (COF) interlayer. The nanofiltration membrane (NF) comprises a base membrane, an interlayer and a separation surface layer. The interlayer is formed by in-situ growth of polyphenol and diamine under the action of an oxidizing agent, and the separation surface layer is formed by an aqueous-phase active monomer and multi-element acyl chloride through an interfacial polymerization reaction. According to the invention, an imino covalent organic framework (TpPa-COF) film interlayer is introduced, and a surface polyamide layer is prepared through interfacial polymerization, so that the hydrophilicity of the film and the ability of removing divalent cations are improved. The invention aims to solve the problem of balance between low flux and high separation effect of an NF membrane in separation of monovalent / divalent cations, maintain ideal water flux while ensuring high separation effect, and solve the problem that a traditional NF membrane separation layer has defects. The two-dimensional TpPa-COF material can effectively control the pore size distribution and hydrophilicity of the surface of the substrate and improve the separation performance of the composite membrane. The preparation method is simple, and the obtained nanofiltration membrane has a wide application prospect.

The invention belongs to the technical field of environmental protection, and provides a preparation method of an imine-modified functionalized mesoporous magnetic silicon dioxide nano material. The method comprises the following steps: synthesizing Fe3O4 magnetic nanoparticles in a Fe < 2 + > / Fe < 3 + > alkaline hydrolysis system through a coprecipitation method; then coating the magnetic nanoparticles with an amorphous silicon dioxide layer by taking TEOS (tetraethoxysilane) as a silicon source by adopting a sol-gel method, so as to prepare magnetic silicon coated nanoparticles; the prepared nano-particles are subjected to secondary silicon coating guided by a cetyl trimethyl ammonium bromide (CTAB) mesoporous template agent, and mesoporous magnetic silicon nano-particles are formed after calcination; and finally, carrying out surface amination modification on the mesoporous magnetic silicon nano-particles by utilizing an amino silane coupling agent, and then carrying out condensation reaction on the mesoporous magnetic silicon nano-particles and various aldehyde derivatives to construct imine bonds, so as to obtain the imine-modified functionalized mesoporous magnetic silicon dioxide nano-material. The imine-modified functionalized mesoporous magnetic silicon dioxide nano-material formed by the invention has the characteristics of efficient adsorption, rapid magnetic recovery and excellent environmental stability, and can effectively remove polystyrene micro-plastics and organic pollutants in a water body.

The invention relates to the technical field of biogenic amine detection, in particular to a dicyanoethylene-based fluorescent material as well as a preparation method and application thereof. After the biogenic amine is in contact with the glass surface fluorescent probe, due to the nucleophilic characteristic of the biogenic amine, the biogenic amine can be subjected to nucleophilic substitution reaction with a probe molecule dicyanovinyl group to generate an imine chemical structure. As the electron-withdrawing capability of dicyanoethylene is stronger than that of imine, the intramolecular charge transfer effect of probe molecules is greatly reduced, so that blue shift of absorption and luminescence properties of the probe molecules is caused, and after the fluorescent probe is loaded on the surface of glass, the fluorescence intensity of the fluorescent probe is improved. The formed dicyanoethylene-based fluorescent material provides a solution for the technical problem that the existing biogenic amine detection mode is inconvenient.

The imine reductase mutant provided by the invention can catalyze asymmetric reductive amination of ethyl 3-formylhexanoate and (S)-2-aminobutanamide to synthesize brivaracetam, two chiral centers of brivaracetam are constructed in one step, and the problems of poor environmental protection property, low atom utilization rate, long route and the like in the existing industrial synthesis route are solved. Wide application prospects are realized.

The invention discloses a copolyimide film with low dielectric constant and low thermal expansion coefficient and a preparation method thereof, and the preparation method comprises the following steps: reacting 0.019-0.021 mol of aromatic dianhydride and 0.017-0.023 mol of diamine unit in 0.45-0.48 mol of solvent, then adding 0.0004 mol of end-capping reagent dissolved in 0.13-0.15 mol of solvent, and reacting to prepare polyamide acid with a main chain containing o-hydroxyl; the diamine unit comprises 10-40 mol% of a monomer with a main chain containing o-hydroxyl and the balance of aromatic diamine; performing film coating and thermal imidization on polyamide acid to prepare a polyimide film; and heating to carry out thermal rearrangement reaction on the o-hydroxyl to obtain the copolyimide film with the main chain containing the oxazole ring. The dielectric constant of the prepared copolyimide film is 2.7-3.0, and the thermal expansion coefficient of the copolyimide film is 19.5-26.5 ppm / K.

The invention relates to a preparation method of a porous polyimide low-dielectric material. The method comprises the following specific steps: preparing a polyamide acid solution with a certain solid content under an ice-water bath condition; after the solution is recovered to normal temperature, adding a certain amount of sodium alginate, and after the solution is homogenized, adding a catalyst and a dehydrating agent for chemical imidization; the method comprises the following steps: coating a substrate medium with a solution after a certain time of reaction, standing in air for a certain time, sequentially and respectively placing the substrate medium in ethanol and a hot water bath for replacement for a certain time, airing at normal temperature, and transferring to a high-temperature oven for gradient cyclization to realize complete imidization. According to the method, conditions are mild and easy to control, and the low-dielectric film material which is flat in appearance and ordered in structure is prepared only through a normal-pressure drying method.

The invention relates to the technical field of organic supramolecular chemical materials, in particular to an octyloxy-modified imine gelator, bi-component gel of the octyloxy-modified imine gelator and a preparation method and application of the octyloxy-modified imine gelator. The gelator is a symmetric o-octyloxy modified p-phenylenedialdehyde-maleonitrile imine gelator, and has an obvious aggregation-induced emission property; the gelator and the cholesteryl half-ester gel can form double-component organic gel without fluorescence emission in an organic solvent; the fluorescence-emission-free double-component gel formed in tert-butyl alcohol is red fluorescence-emission gel when meeting water, and is converted into blue fluorescence-emission gel when meeting NaClO, so that water and NaClO can be rapidly and intuitively detected; the gelator has fluorescence enhancement and blue shift after encountering NaClO in a solution state, has fluorescence'off-on 'detection on NaClO, has fluorescence emission intensity reduced after Hg < 2 + > is added in the solution state, and has fluorescence'on-off' detection performance on Hg < 2 + >.

The invention provides a polyimide multilayer composite membrane material as well as a preparation method and application thereof, and belongs to the technical field of gas separation. According to the method, through collaborative design of a functional support layer, a gradient MOF layer and an ultrathin selection layer structure, the problems of support layer pore seepage, MOF agglomeration, weak interface bonding and the like in an existing composite membrane material are solved. The preparation method comprises the following steps: firstly, carrying out electrostatic spinning on a polyamide acid glue solution, and synchronously introducing dopamine by adopting a chemical imidization method to prepare a functionalized polyimide fiber membrane containing hydroxyl and amino on the surface, so that the mechanical property of a supporting layer and the MOF anchoring capability are remarkably improved; growing MOF layers with different particle sizes on the surface of the fiber membrane by regulating and controlling the concentration gradient of ligand / metal salt and the reaction time, and passivating through a silane coupling agent after each step of growth so as to avoid heterogeneous nucleation and construct a gradient structure; after the MOF gradient layer is subjected to Ar plasma pretreatment to introduce hydroxyl, the ultrathin polyamide selection layer is formed by utilizing interfacial polymerization of fluorine-containing acyl chloride and a macrocyclic amine monomer, and the ultrathin polyamide selection layer is suitable for gas separation work.

The present application relates to the technical field of polyimides and relates to a preparation method for a high-performance polyimide and an application thereof, aiming to solve the problems in the prior art such as numerous side reactions and severe impact on transparency caused by an excessively high imidization reaction temperature during the use of a high-temperature thermal imidization method for the preparation of polyimides. The preparation method comprises: (1) preparing a polyamic acid solution; (2) adding a chemical catalyst and a polyamic acid solution to partially complete an imidization reaction; (3) adding an end group auxiliary agent, performing coating with the solution, heating, and maintaining the heat to complete the imidization reaction; and (4) carrying out high-temperature treatment to obtain a high-performance polyimide. The present application can significantly reduce numerous side reactions present in a traditional imidization reaction, eliminate an adverse effect of high-temperature imidization on the optical performance, greatly improve the mechanical properties, heat resistance, optical performance, etc. of a material, and also achieve both high heat resistance and high transparency.

The invention relates to the technical field of organic material detection, in particular to an imine molecular sensor with a five-detection function, two-component gel as well as a preparation method and application of the imine molecular sensor. The imine molecular sensor has three signal responses of fluorescence on-off, ultraviolet absorption and color change to Fe < 3 + >, Co < 2 + > and Ni < 2 + > in a solution state, and has ultraviolet absorption and fluorescence on-off dual-detection performance to acid and alkali changes; the imine molecular sensor and cholesteryl half ester can form two-component gel through a heating-low-temperature ultrasonic cooling method; after Fe < 3 + >, Co < 2 + >, Ni < 2 + >, NaOH and HCl are respectively added, the orange of the gel becomes milky white, reddish brown, transparent red, milky white and milky white under sunlight, and the fluorescence of the orange of the gel disappears under an ultraviolet lamp, so that the rapid and sensitive detection of Fe < 3 + >, Co < 2 + >, Ni < 2 + >, acid and alkali under two states of the imine molecular solution and the gel is realized. The imine molecular sensor provided by the invention has the advantages of mild synthesis conditions, simple preparation and the like, and creates favorable conditions for popularization and application of the imine molecular sensor.

The invention relates to the technical field of polyurethane acrylate, and particularly discloses dual-curing polyurethane acrylate resin and a preparation method thereof. Wherein the dual-curing polyurethane acrylate resin is prepared from the following raw materials: polyester polyol, polyether polyol, diisocyanate, hydroxyl acrylate, a chain extender, a photoinitiator, cardanol glycidyl ether, a polymerization inhibitor and modified nanoparticles. Wherein the citric acid and the polyethyleneimine are adopted to carry out synergistic modification on the nano particles, the dispersion stability of the nano particles is improved, so that the mechanical property of the resin is improved, the cardanol glycidyl ether and the photoinitiator generate a synergistic effect, and the resin can be quickly shaped through photocuring promoted by the photoinitiator; the cardanol glycidyl ether participates in the subsequent thermocuring reaction, so that the curing effect is improved, and the adhesive force between the film layer and the base material is enhanced.

The invention provides an imine covalent organic polymer and a preparation method thereof, a negative electrode material and a potassium ion battery. The preparation method comprises the following steps: carrying out first mixing on raw materials including a carbonyl-containing first organic compound, an amino-containing second organic compound and a dispersion liquid to obtain a mixed liquid; carrying out in-situ polymerization reaction on the mixed solution to obtain an imine covalent organic polymer; wherein the first organic compound is nitro-substituted or non-substituted pyrene-4, 5, 9, 10-tetraketone; the second organic compound is selected from any one or more of C6-C12 aromatic amine compounds, C6-C12 heteroaromatic amine compounds and amino-substituted C4-C6 cyclic compounds, and the number of amino groups in each molecule of the second organic compound is greater than or equal to 2. The covalent organic polymer obtained by the preparation method can solve the problem that the structure is easily stacked and is easily dissolved in electrolyte to be damaged when the covalent organic polymer is used as a negative electrode material.

The invention belongs to the technical field of nano magnetic beads, and relates to a carboxyl nano magnetic bead and application thereof in DNA capture and DNA release. The invention discloses a preparation method of carboxyl nano magnetic beads, which comprises the following steps: dissolving iminodiacetic acid in a sodium hydroxide solution, stirring in an ice bath, dropwise adding a silane coupling agent, carrying out a first heating reaction, cooling in the ice bath, dropwise adding the silane coupling agent again, carrying out a second heating reaction, and cooling in the ice bath to obtain a carboxyl silane coupling agent; and dispersing the ferroferric oxide / silicon dioxide hydroxyl magnetic compound and a carboxyl silane coupling agent in an organic solvent, and stirring for reaction to obtain the carboxyl nano magnetic beads. The carboxyl nano magnetic bead is a nano-scale magnetic bead, is large in specific surface area, good in suspension property and not easy to settle, and has multiple sites for DNA binding; the method can be used for effectively extracting DNA ladders and cfDNA in nucleic acid capture and nucleic acid release.

The invention relates to the technical field of biochemical engineering, in particular to a method for preparing chiral alpha-trifluoromethyl alcohol by using imine reductase AtRedAm, trifluoromethyl ketone is reduced into corresponding chiral trifluoromethyl alcohol at an excellent conversion rate by using the imine reductase AtRedAm, and enantioselectivity is high. The reaction depends on an NADPH (Nicotinamide Adenine Dinucleotide Phosphate) coenzyme circulation system, 10% dimethyl sulfoxide is used as a reaction cosolvent, the reaction is carried out in a 100mM (pH = 7.5) phosphate buffer solution for 16 hours, the highest molar conversion rate reaches 99%, and the highest optical purity reaches 95%.

The invention provides a preparation method of NMN nano microspheres with high stability, and belongs to the technical field of NMN. The preparation method comprises the steps of NMN pretreatment, primary microsphere preparation, functional microsphere preparation and mixing. The preparation method of the primary microspheres comprises the following steps: adding epsilon-polylysine and glutathione into an ethanol solution, uniformly stirring, adding 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide, and stirring for 28-32 minutes to obtain a mixed solution; adding the pretreated NMN solution into the chitosan solution, then adding the mixed solution, and carrying out heat preservation at 44-50 DEG C for 2.8-3.2 h to obtain primary microspheres; the NMN nano-microsphere prepared by the method disclosed by the invention is good in stability and good in slow release performance.

The invention discloses a kind of preparation method of amino hyperbranched siloxane and its modified polyimide aerogel material.First, alkoxysilane X with amino active functional group, alkoxysilane Y of inactive functional group and water are carried out autocatalytic controlled hydrolysis condensation under sub-stoichiometric ratio, obtain multifunctional group (such as other active groups, alkoxyl group, amino) amino hyperbranched siloxane liquid (HPSi NH2) with controllable amino content, then using HPSi NH2 as cross-linking agent and anhydride-terminated polyamic acid solution reaction to obtain functionalized polyamic acid, which is stirred with tertiary amine and deionized water to obtain functionalized polyamic acid wet gel, which is passed through freeze drying, high temperature imidization treatment to obtain amino hyperbranched siloxane modified polyimide aerogel material. This material has excellent flexibility, resilience, heat resistance and flame retardancy, and can be applied to aerospace, communication, catalysis and filtration fields.

The invention relates to the technical field of water treatment, in particular to a reverse osmosis membrane and a preparation method thereof. The preparation method of the reverse osmosis membrane comprises the following steps: soaking a base membrane in a water phase solution, taking out the base membrane, drying the surface of the base membrane, coating the base membrane with an oil phase solution, carrying out interfacial polymerization reaction, curing, coating with a modifier solution, and drying to obtain the reverse osmosis membrane, the modifying agent comprises 2, 4, 6-tri (4-aminophenyl)-1, 3, 5-triazine-1, 3, 5-tri (4-methyl phenyl) benzene. The successfully grafted COFs can improve the water permeability of the membrane to a certain extent, and also can improve the pollution resistance, acid resistance and oxidation resistance of the membrane, so that the service life of the membrane is prolonged. According to the invention, different effects of the same type of imino COFs introduced to the reverse osmosis membrane are further compared, so that the excellence of the selected imino COFs is highlighted.

The present invention relates to the field of water treatment technology, and more particularly to a kind of reverse osmosis membrane and preparation method thereof.The preparation method of the reverse osmosis membrane includes:Basement membrane is soaked in aqueous phase solution, after taking out surface drying, oil phase solution is coated on basement membrane and carries out interfacial polymerization reaction, after solidification, coating modifier solution, after drying, obtain reverse osmosis membrane;The modifier includes 2,4,6-tris (4-aminophenyl) ‑1,3,5-triazine ‑1,3,5-tris (4-methylphenyl) benzene.The COFs successfully grafted by the present invention can improve the water permeability of membrane to a certain extent, and can also improve the anti-pollution property, acid resistance and oxidation resistance of membrane, and then improve the service life of membrane.The present invention further compares the different effects that the same type of imino COFs are introduced into reverse osmosis membrane, so as to highlight the excellence of the imino COFs selected by the present invention.

The invention provides a nanoparticle capable of releasing EGCG (epigallocatechin gallate) in response to ROS (reactive oxygen species) as well as a preparation method and application of the nanoparticle. The nanoparticles comprise a carrier and EGCG (epigallocatechin gallate) loaded on the carrier; the carrier is Prussian blue nanoparticles of which the surfaces are modified with polyethyleneimine and phenylboronic acid compounds. The preparation method of the nanoparticles is simple and easy to operate, the nanoparticles are good in dispersity, and through research, the nanoparticles have CAT-like, SOD-like and other multi-enzyme activities, can remove. OH, have a high EGCG drug loading rate and release EGCG in the presence of ROS. Besides, the nanoparticles show a good effect of improving myocardial ischemia reperfusion injury in cell level and rat in-vivo experiments, through comparison of EGCG and PB NPs single-drug treatment, synergistic treatment in the composite material achieves an effect of '1 + 1 > 2', and the composite material has good biological safety.

The invention relates to the field of copper-clad plates, and discloses a high-performance flame-retardant low-dielectric-loss copper-clad plate and a preparation method thereof.The copper-clad plate comprises epoxy resin, benzoxazine resin, composite filler, carboxyl-terminated nitrile rubber, an active diluent, a curing agent and the like; the composite filler is prepared by compounding flame-retardant modifier grafted graphene oxide and epoxy silane modified silicon dioxide hollow spheres; according to the flame-retardant modifier, boric acid and pentaerythritol are used for preparing a double-terminal hydroxyl boron-containing intermediate, then dichlorodiphenyl silane and phenylphosphonic dichloride react with hydroxyl groups at the two ends of the intermediate to prepare a flame-retardant intermediate, and amino silane and vanillic aldehyde react with chlorine atoms at the two ends of the intermediate to prepare an aldehyde modified flame-retardant intermediate; the copper-clad plate prepared by the preparation method disclosed by the invention is low in dielectric constant and dielectric loss, high in heat conductivity coefficient and good in flexibility, and also has excellent heat resistance and flame retardance.

The invention discloses a preparation method of a 3-micron ultrathin lithium battery copper foil. The preparation method comprises the following steps: preparing a copper sulfate electrolyte; a wetting agent, a brightening agent and a high resistance agent are added into the copper sulfate electrolyte, the high resistance agent is at least one of thiazolidinethione, polyethyleneimine, 2-mercaptobenzimidazole and ethylene thiourea, and a mixed additive is formed; polishing and grinding a cathode roller by adopting a flying wing wheel, and carrying out electrolytic treatment on the mixed additive through the polished and ground cathode roller to obtain a first-stage copper foil; and the first-stage copper foil is placed in a nitrogen furnace to be subjected to annealing treatment, and the 3-micron ultrathin lithium battery copper foil is obtained. The invention aims to solve the technical problems that in the prior art, edge tearing, foil breaking, warping, dark appearance oxidation and the like are prone to occurring in the production process of the ultrathin copper foil, the tensile strength and the ductility are difficult to consider at the same time, and stable mass production of the 3-micron copper foil is still difficult.

The invention discloses an omariglitazone intermediate as well as a synthesis method and application thereof, and belongs to the technical field of pharmaceutical chemistry synthesis. The invention provides a synthesis method of an omarigliflozin intermediate and application of the intermediate in synthesis of omarigliflozin. The key of the synthesis method provided by the invention lies in the deprotection process of polycyclic indole amide, nitrile groups are not hydrolyzed, indole carboxylic acid is generated with high selectivity, molecular lactamization is avoided in the condensation process with polycyclic imine B, and expensive amidation reagents such as HATU are not needed in the process, so that the synthesis method is simple and easy to implement. And the purpose of preparing omariglitazone with low cost and high yield is achieved. The synthesis method has the advantages of easily available raw materials, mild reaction conditions, small side reaction influence, simplicity and convenience in operation and high yield, improves the yield, is easy to purify, and is suitable for industrial production of omariglitazone.

The invention provides an exosome enrichment method based on a modified cellulose material, which comprises the following steps: carrying out TEMPO oxidation on plant residue cellulose to prepare a cellulose material with a carboxyl structure; the cellulose structure is further refined by adopting mechanical shearing and high-pressure homogenizing means, so that the specific surface area and the dispersion stability are remarkably improved; through polyethyleneimine PEI grafting, a large number of amino functional groups are introduced, the surface electropositivity of the material is enhanced, and efficient adsorption and enrichment of exosomes with negative charges are achieved. The invention also provides the exosome prepared by the method. The modified cellulose material disclosed by the invention is wide in source, simple and convenient to prepare and mild in enrichment process, the separation purity and the enrichment efficiency of the exosome can be remarkably improved, and the modified cellulose material has good biocompatibility and environmental friendliness; compared with existing ultracentrifugation, density gradient centrifugation and immunoaffinity separation methods, the method has the advantages that the operation process is simplified, the equipment dependence and reagent cost are reduced, and the potential of large-scale production and clinical application is achieved.

The invention provides a resin composition, a secondary curing preparation method and application thereof. The resin composition is prepared from the following components in parts by weight: 12 to 48 parts of modified acrylate prepolymer, 2 to 30 parts of polycyclic carbonate, 3 to 30 parts of monomer and 0.1 to 0.5 part of photoinitiator, and the modified acrylate prepolymer contains a multi-element imine group. According to the invention, the modified acrylate prepolymer containing the multi-element imine group is introduced, and the modified acrylate prepolymer, the multi-element cyclic carbonate, the photocuring monomer and the photoinitiator have a synergistic effect, so that the resin composition capable of being photocured and secondarily cured is obtained. The obtained resin composition has a long storage period of validity, and can form a more stable network structure after 3D printing, curing molding and secondary curing, so that the 3D printing resin has higher strength and elasticity after final curing molding.

The invention relates to a particulate composition comprising, or substantially consisting of, urea, an inhibitor, preferably a urease inhibitor and / or a nitrification inhibitor, and an additive, wherein the additive comprises components (i), (ii), and optionally (iii): (i) one or more polyhydric alcohols; preferably one or more carbohydrates, preferably selected from monosaccharides, disaccharides, and oligosaccharides; (ii) a first polymer, preferably an amine-containing polymer; more preferably a polyvinylamine or a polyalkyleneimine; and (ii) optionally, a second polymer, preferably a polar polymer; more preferably a water-soluble polar polymer. The invention further relates to a process for producing the particulate composition, an additive for a particulate composition, and the use of the particulate composition as a fertilizer.

The invention discloses a nitrogen-containing carbon hollow sphere supported cobalt-based catalyst as well as a preparation method and application thereof, and belongs to the technical field of catalyst preparation. According to the preparation method, ammonia water, tetraethyl orthosilicate, polyoxyethylene polyoxypropylene ether triblock copolymer, resorcinol and a formaldehyde solution are fully reacted in a mixed solvent of deionized water and ethanol by virtue of a template method, and the nitrogen-containing carbon hollow spheres are obtained after calcination and etching; then carrying out surface modification on the nitrogen-containing carbon hollow spheres, and uniformly loading cobalt metal by virtue of the structure guiding effect of hexamethyleneimine and sodium citrate dehydrate; the prepared nitrogen-containing carbon hollow sphere supported cobalt-based catalyst has abundant highly-exposed Co-N-C active sites, has wide substrate universality, has good catalytic activity and selectivity for amination reactions with various long-chain fatty aldehydes, fatty ketones, cyclic fatty ketones, aromatic aldehydes and ketones as raw materials, and can realize efficient catalytic amination reactions of carbonyl compounds.