1293 results about "Glutaraldehyde" patented technology

The invention discloses a compound enzyme preparation for improving the absorption and utilization rate of a fertilizer and a preparation method thereof, and belongs to the technical field of enzyme preparations. The compound enzyme preparation is prepared from the following components in parts by weight: 100 parts of purified water, 6 to 8 parts of modified cellulase, 10 to 12 parts of immobilized protease, 10 to 12 parts of phosphatase, 10 to 14 parts of urease, 8 to 10 parts of nitrate reductase, 10 to 12 parts of pectinase, 8 to 10 parts of chitinase, 6 to 8 parts of xylanase, 10 to 12 parts of beta-glucosidase, 10 to 12 parts of superoxide dismutase and 4.5 to 6 parts of a microbial agent, the modified cellulase is obtained by chemically modifying cellulase; the immobilized protease is prepared by the following steps: adsorbing activated and coupled modified polylactic acid and a protease solution, crosslinking with glutaraldehyde, filtering, washing and drying. The compound enzyme preparation improves the fertilizer absorption and utilization rate of plants.

The invention discloses a preparation method of a degradable transparent conductive polymer film, and belongs to the technical field of film preparation. Preparing dispersion liquid I through graphene oxide quantum dots; preparing a dispersion liquid II from polyaniline nanofibers; dissolving pyrrole and toluenesulfonic acid in N, N-dimethylformamide to prepare a reaction solution, adding the dispersion liquid I and the dispersion liquid II, stirring, and adding ferric chloride hexahydrate to obtain a reaction solution; adjusting the pH value of the reaction solution to 1.5, and heating to obtain a polypyrrole solution; preparing cellulose acetate, polyvinyl alcohol and N, N-dimethylformamide to obtain a cellulose acetate solution; mixing the polypyrrole solution and the cellulose acetate solution, adding glutaraldehyde to obtain a mixed solution, and pouring the mixed solution into a mold to prepare a composite wet film; and putting the composite wet film into a hot-pressing forming machine for hot-pressing to generate the polymer film. The conductive polymer film prepared by the invention can be applied to the fields of supercapacitor electrode materials, electromagnetic shielding materials, flexible sensors and the like, and provides a new high-performance material choice for the development of related fields.

The invention discloses a method for preparing lubricating oil microspheres based on a microfluidic technology. The method comprises the following steps: preparing an external phase solution, an intermediate phase solution, an internal phase solution and a collection solution; firstly, the internal phase solution is introduced into the micro-fluidic chip, and after the flow of the internal phase solution is stable, the intermediate phase solution is introduced into the micro-fluidic chip to be sheared with the internal phase solution to form nuclear layer liquid drops. After the core layer liquid drops are generated stably, the external phase solution is introduced into the micro-fluidic chip to be sheared with the core layer liquid drops, so that the external phase solution wraps the outer layer of the core layer to form a shell layer with a core-shell structure, and then the double liquid drops are dropped into a collecting solution containing glutaraldehyde to be crosslinked and cured to form the chitosan lubricating oil microspheres. The chitosan lubricating oil microsphere has the following beneficial effects that the lubricating oil is wrapped in the microsphere through a microfluidic technology, so that the chitosan lubricating oil microsphere is of a core-shell structure, and when the lubricating oil is needed, the lubricating oil in the microsphere is released to improve the friction performance of parts.

The invention provides a super-hydrophobic / super-oleophylic degradable photo-thermal aerogel adsorption material and demulsification performance thereof, and belongs to the technical field of oil-water separation materials, and the super-hydrophobic / super-oleophylic degradable photo-thermal aerogel adsorption material is prepared by the following steps: (1) extracting cellulose from waste cartons and performing ultrasonic dispersion to prepare a cellulose suspension; (2) preparing a chitosan solution; (3) mixing the cellulose suspension and the chitosan solution to obtain a cellulose / chitosan composite solution, adding nano carbon black particles, glutaraldehyde and a methyltrimethoxysilane aqueous solution into the cellulose / chitosan composite solution, and stirring; (4) injecting the mixed solution into a mold, and performing directional freezing on a semiconductor refrigeration platform; and (5) performing freeze drying on the frozen sample, and then putting the frozen sample into a drying oven for cross-linking to obtain the aerogel. The aerogel is obtained by taking cellulose extracted from waste cartons and chitosan as organic frameworks, carrying out chemical crosslinking through glutaraldehyde, introducing nano carbon black particles as photo-thermal components and carrying out hydrophobic modification through methyltrimethoxysilane, and has an excellent pore structure, super-hydrophobicity-super-lipophilicity and excellent mechanical properties; the adsorbent has efficient adsorption capacity on high-viscosity crude oil; and the device can be repeatedly used and is biodegradable, so that the burden on the environment is reduced.

The invention discloses a method for detecting glufosinate-ammonium residues in coffee in dual modes of colorimetry and chemiluminescence, and belongs to the technical field of chemical analysis and detection.The method comprises the steps that Schiff base formed by 4-aminoantipyrine and glutaraldehyde serves as a complexing agent of Cu < 2 + >, and then a copper-doped carbon dot Cu-CDs nano-enzyme is prepared through microwave digestion; according to the present invention, the Cu-CDs nano-enzyme has excellent peroxidase-like activity, can oxidize the colorless 2, 2 '-biazo-bis-3-ethylbenzothiazoline-6-sulfonic acid into the blue-green oxidized ABTS, and can improve the chemiluminescence intensity of the reaction of N-(4-aminobutyl)-N-ethylisoluminol and H2O2 by nearly 100 times when the Cu-CDs nano-enzyme is used as the chemiluminescence catalyst; based on the inhibition effect of glufosinate-ammonium on the activity of Cu-CDs POD, a sensitive and rapid colorimetric and chemiluminescence two-channel GM detection technology is developed, and the method has potential application value in the aspect of coffee safety monitoring.

The invention discloses a low-smoke flame-retardant cable outer layer material, and a preparation method of key components and a high-entropy alloy nano material comprises the following steps: grinding cerous nitrate, ferric nitrate, manganous nitrate, sodium hexahydroxyplatinate and copper nitrate into particles according to a ratio of 2: 1: 1: 1: 1; then adding 10-20 times by mass of a 32% tannic acid solution and 5-8 times by mass of a 10% glutaraldehyde solution, carrying out an oil bath at 65-70 DEG C for a reaction for 4-8 h, then carrying out overnight vacuum freeze drying to obtain mixed powder, placing the mixed powder in a crucible of a muffle furnace, then calcining the mixed powder at 1000-1200 DEG C under the protection of nitrogen flow for 4-10 h, and finally cooling the calcined mixed powder to room temperature. And cooling. The prepared outer layer material for the cable overcomes the defects that a conventional cable easily releases a large amount of toxic smoke during combustion, is poor in flame retardant property and contains halogen to pollute the environment.

The invention discloses nano-porous aerogel based on carboxymethyl chitosan as well as a preparation method and application of the nano-porous aerogel, and belongs to the technical field of biomass-based aerogel. The aerogel is prepared from the following raw materials in parts by weight: 2.5 parts of deionized water, 0.075 part of carboxymethyl chitosan (CMC), 0.0075 to 0.0225 part of carboxylated multi-walled carbon nanotubes (C-CNT), 0.01125 part of glutaraldehyde (GA), 0.01 part of poly (3, 4-ethylenedioxythiophene)-poly (styrene sulfonic acid) (PEDOT: PSS) and 10 parts of dimethyl sulfoxide (DMSO). According to the preparation method, CM C is used as a matrix, C-CNT is used as an internal conductive material and a strength enhancing material, hydrogel is formed under the action of a cross-linking agent GA, and CMC / C-CNT aerogel is prepared through directional freeze drying; cMC / C-CNT is taken as a substrate, then PEDOT: PSS is dip-coated to obtain CMC / C-CNT / PEDOT: PSS, the CMC / C-CNT / PEDOT: PSS is taken as an external conductive substance, the CMC / C-CNT / PEDOT: PSS and internal C-CNT form a double-conductive network, aerogel with excellent conductive performance and mechanical performance is prepared, the prepared aerogel is used for preparing an aerogel sensor, and the prepared sensor has high mechanical performance and high electrical performance.

The invention relates to the technical field of formaldehyde adsorption, in particular to a preparation method of modified activated carbon for removing formaldehyde, which comprises the following steps: S1, performing acidification pretreatment on coconut shell charcoal, and grafting the pretreated coconut shell charcoal with polyethyleneimine to obtain activated carbon loaded with polyethyleneimine; s2, carrying out dipping treatment and cyclohexanol treatment on the activated carbon loaded with polyethyleneimine to obtain functionalized activated carbon; s3, reacting the magnesium-aluminum hydrotalcite with a quaternary ammonium salt solution and a sodium benzenesulfonate solution to obtain modified hydrotalcite; reacting the modified hydrotalcite with a vinyl silane coupling agent to obtain vinyl hydrotalcite; s4, the vinyl hydrotalcite and 4-amino-3-hydrazino-5-sulfydryl-triazole are subjected to a reaction, and secondary modified hydrotalcite is obtained; and S5, dispersing the secondary modified hydrotalcite and the functionalized activated carbon in water, and adding glutaraldehyde to obtain the modified activated carbon. The modified activated carbon prepared by the preparation method disclosed by the invention realizes selective recognition, efficient adsorption and catalytic degradation of formaldehyde.

The invention provides a preparation method of immobilized D-psicose-3-epimerase, which comprises the following steps: firstly aminating inorganic silicon nanoflowers, then activating by using a cross-linking agent glutaraldehyde, finally adding enzyme liquid, reacting in a shaking table for a period of time, and centrifuging and washing the reactant to obtain the product, namely the immobilized D-psicose-3-epimerase. The enzymatic activity and the stability of the immobilized enzyme are obviously improved, the specific enzyme activity of the immobilized enzyme is 446.44-1033.09 U / g protein, the activity of the immobilized enzyme is 163.09% and 181.53% of that of free enzyme after the immobilized enzyme is incubated for 6 h under the condition that the temperature is 30 DEG C or the pH value is 5, 63.18-70.78% of the initial activity is still reserved after the immobilized enzyme is repeatedly used for 10 times, and 46.27-54.38% of the initial activity is still reserved after the immobilized enzyme is stored for 15 days. The immobilized enzyme can catalyze fructose to generate psicose, and a green and efficient preparation technology is provided for production of psicose.

The present invention relates to a kind of silk fibroin hydrogel and preparation method thereof, silkworm raw silk is degummed, sol, dialyzed, filtered, freeze-dried to obtain silk fibroin freeze-dried powder, then redissolved into high concentration silk fibroin solution, filtered and spray-dried into silk fibroin microspheres; silk fibroin microspheres are slowly added to a phosphate buffered saline solution containing γ-polyglutamic acid and glutaraldehyde, stirred and ultrasonically carried out the first cross-linking, then a cross-linking agent solution is added, stirred evenly and ultrasonically, and the second cross-linking is carried out, and the silk fibroin hydrogel is obtained after being rinsed with pure water after being placed for a period of time. In the preparation method of the present invention, a phosphate buffered saline solution containing γ-polyglutamic acid and glutaraldehyde is used as a cross-linking agent and secondary cross-linking is carried out, and the prepared silk fibroin hydrogel silk fibroin has a long retention time, good stability and mechanical strength, and the cross-linking method is simple, and it is suitable for large-scale industrial production.

The invention relates to the technical field of hydrogel, in particular to a preparation method and application of EGCG-mediated hydrogel, a lysozyme solution is heated under the acidic condition to form lysozyme amyloid fibrils LAFs, EGCG is dissolved in a buffer solution and mixed with the LAFs solution obtained in the step 1 in proportion to form an LAFs-EGCG compound, and the EGCG-mediated hydrogel is prepared. The chitosan CS is dissolved in an acetic acid buffer solution, glutaraldehyde is added to serve as a cross-linking agent, the mixture is mixed with the LAFs-EGCG compound obtained in the step 2 and stirred, the composite hydrogel is formed, the concentration of EGCG is 0.2-1.0 wt%, the concentration of LAFs is 5 wt%, the concentration of chitosan is 2 wt%, the pH value of the lysozyme solution in the step 1 is 2.0, the heating temperature is 77 DEG C, the heating time is 10 hours, the concentration of EGCG in the step 2 is 0.4-0.8 wt%, and the pH value of the lysozyme solution in the step 2 is 1.5-2.5. In the step 3, the concentration of glutaraldehyde is 2%, the storage modulus G'of the hydrogel is 325-480 Pa, the hardness is 2176.71 g, and the bacteriostasis rate on staphylococcus aureus and salmonella exceeds 95%.

The invention relates to the technical field of lithium batteries, in particular to a preparation method of an inorganic-organic composite binder for a silicon negative electrode battery. The modified chitosan is obtained by adding chitosan, ammoniated urushiol, an acetic acid solution and vanillin. And mixing the modified chitosan, guar gum, an acetic acid solution and glutaraldehyde to obtain the biomass binder. And adding deionized water to sequentially obtain a biomass binder solution, a boric acid solution, a lithium metasilicate solution and a polyvinyl alcohol solution. And adding the inorganic binder solution and the biomass binder solution into the polyvinyl alcohol solution, and fully stirring to obtain the composite binder. The composite binder prepared by the preparation method disclosed by the invention has good adhesive property and mechanical property, so that the composite binder has a wide application prospect in the technical field of lithium batteries.

The invention provides a modified porous chitosan gel bead, a preparation method thereof and application of the modified porous chitosan gel bead in cobalt-nickel separation, and belongs to the technical field of chitosan preparation. The preparation method comprises the following steps: firstly, modifying chitosan by using polyethylene glycol and glutaraldehyde to obtain a porous chitosan gel bead with a cross-linked structure, and then grafting by using epichlorohydrin, ethylenediamine and 2-chloromethylpyridine hydrochloride to obtain the modified porous chitosan gel bead containing an aminomethylpyridine functional group. The modified porous chitosan gel bead has excellent selective adsorption on nickel ions in a cobalt-nickel solution with the pH value range of 2-5, and nickel-cobalt separation can be achieved. In addition, the modified porous chitosan gel bead also has a good nickel-cobalt separation effect in a salt-containing system. The preparation method of the modified porous chitosan gel bead provided by the invention is simple in process, and the raw material chitosan is wide in source, non-toxic and environment-friendly.

The invention discloses a solar interface evaporator and a preparation method and application thereof. The evaporator comprises a porous cellulose supporting layer and a photo-thermal composite hydrogel layer loaded on the cellulose supporting layer, and the porous cellulose supporting layer and the photo-thermal composite hydrogel layer are combined in a gel in-situ cross-linking mode to form an integrated composite structure. The photo-thermal composite hydrogel layer is composite hydrogel formed by cross-linking polyvinyl alcohol, chitosan quaternary ammonium salt and carbon black. The preparation method comprises the following steps: adding polyvinyl alcohol and chitosan quaternary ammonium salt into a solvent to form a transparent mixed solution, adding the carbon-based photothermal conversion material, and continuously heating and stirring to prepare a hydrogel precursor solution; then adding glutaraldehyde and hydrochloric acid, and carrying out cross-linking reaction to form a hydrogel system; and immersing the cellulose sponge, standing, circularly and alternately freezing and unfreezing, and finally freeze-drying to obtain the product. The evaporator disclosed by the invention integrates highlight absorption, high heat utilization, water transportation, salt resistance and antibiosis, can realize large-scale production, and is suitable for scenes such as seawater desalination, sewage purification and emergency water supply.

The invention relates to the field of drain pipes, and discloses an antibacterial polypropylene noise-reduction drain pipe and a preparation method thereof, the antibacterial polypropylene noise-reduction drain pipe comprises polypropylene, modified glass fiber, an antibacterial additive, a compatilizer and a stabilizer; the modified glass fiber is prepared by performing formylation modification on glass fiber by using 3-aminopropyltriethoxysilane and glutaraldehyde, grafting triethylene tetramine and DOPO into a glass fiber structure, and then grafting a hindered phenol antioxidant; the antibacterial additive is prepared by compounding chitosan Schiff base and modified nano titanium dioxide, the chitosan Schiff base is prepared by utilizing a Schiff base reaction between chitosan and vanillin, and the modified nano titanium dioxide is prepared by utilizing isocyanate propyl triethoxy silane and ethyl glycolate to modify nano titanium dioxide. By adding the modified glass fiber and the antibacterial additive, the pipe is endowed with excellent heat resistance, aging resistance, flame retardance and antibacterial performance.

The invention discloses riboflavin photodynamic antibacterial hydrogel for a diabetes wound dressing as well as preparation and application of the riboflavin photodynamic antibacterial hydrogel, and belongs to the technical field of biomedical materials. The hydrogel is prepared from carbomer 941, rhizoma bletillae polysaccharide and carboxymethyl chitosan through physical and chemical bi-crosslinking, glutaraldehyde and carboxymethyl chitosan are added to form dynamic imine bonds, and the stability and adaptability of the hydrogel are enhanced. Meanwhile, the photosensitizer riboflavin is introduced, so that the hydrogel is endowed with photodynamic sterilization characteristics, efficient antibiosis is realized, and rapid healing of diabetic wounds is promoted. The hydrogel has excellent wound environment adaptability and adhesion performance, and is suitable for complicated wound surfaces of diabetes mellitus. The successful research and development of the invention provide reference for the development of novel photodynamic wound dressings, have wide application prospects, provide better treatment choices for diabetics, and are helpful for accelerating wound healing, reducing infection risks and improving the life quality of patients.

The invention discloses high-specific-surface-area micro-mesoporous biomass porous carbon as well as a preparation method and application thereof. The method comprises the following steps: performing hydrothermal catalytic reaction on tobacco stems in an H2O2 solution to loosen a compact structure and increase oxygen-containing functional groups, fully mixing pretreated tobacco stem hydrothermal carbon and sodium lignin sulfonate in an aqueous solution in a solid-liquid form, adding glutaraldehyde to perform cross-linking reaction, and drying to obtain the tobacco stem hydrothermal carbon / sodium lignin sulfonate composite material. The preparation method comprises the following steps: preparing CaCO3 and tobacco stem into a composite biomass charcoal source with a stable three-dimensional network structure, preparing a composite biomass / CaCO3 precursor through an in-situ coprecipitation method, and finally carrying out high-temperature carbonization to obtain the tobacco stem / lignin composite porous carbon with a micro-mesoporous structure, a high specific surface area and a stable structure. The porous carbon material not only has abundant and mutually communicated hierarchical porous structures and high specific surface area, but also contains abundant active oxygen-containing functional groups, so that the surface characteristics of the porous carbon are improved, more adsorption sites can be provided, and the adsorption performance of the porous carbon material is greatly improved.

The invention relates to the technical field of wastewater treatment, in particular to a multistage composite adsorbent for treating petrochemical wastewater and a preparation method thereof.The preparation method comprises the steps that S1, plant straw powder and 3-aminopropyltriethoxysilane are subjected to a constant-temperature reaction, and aminated plant straw is obtained; s2, carrying out hydrothermal reaction on the aminated plant straw and a cerium nitrate solution to obtain functionalized plant straw; s3, the halloysite nanotubes, glutaraldehyde and the functionalized plant straw are stirred for a reaction, high-temperature carbonization is conducted after the reaction is completed, and composite biochar is obtained; s4, carrying out a reaction on the composite biochar and an amino silane coupling agent to obtain aminated composite biochar; s5, calixarene, toluene diisocynate and the aminated composite biochar are subjected to a reaction, and the multi-stage composite adsorbent is obtained. According to the technical scheme, the comprehensive adsorption capacity and removal efficiency of various organic pollutants in the petrochemical wastewater are improved, and the defect that a traditional adsorbent is poor in selectivity is overcome.

The invention discloses a fruit and vegetable exosome extraction method based on ligand fishing. The fruit and vegetable exosome extraction method comprises the following steps: suspending amino-functionalized Fe3O4 (at) SiO2 nanoparticles in a glutaraldehyde solution, and adding activated agglutinin to obtain Fe3O4 (at) SiO2-agglutinin nanoparticles; adding a glutaraldehyde solution into agarose gel to obtain a size exclusion chromatographic column filler; the method comprises the following steps: dispersing Fe3O4 (at) SiO2-lectin nanoparticles in a PBS buffer solution to obtain a uniform suspension, adding the uniform suspension into a size exclusion chromatographic column filler to obtain a uniform slurry, filling the size exclusion chromatographic column with the uniform slurry, and flushing with the buffer solution to form a magnetic bead stationary phase; and loading fruit and vegetable supernatant into a size exclusion chromatographic column, passing through the magnetic bead stationary phase, cleaning residual impurities combined on the exosome-magnetic bead compound by using a buffer solution, and dissociating the exosome from the magnetic beads by using a competitive eluent of the exosome to obtain the high-purity fruit and vegetable exosome. The problem that an existing exosome extraction method is difficult to meet the requirements of high efficiency, simplicity, high purity and high activity at the same time is solved.

The invention relates to the technical field of degradable materials, and discloses an environment-friendly degradable polylactic acid straw and a preparation process thereof. Comprising the following operation steps: step 1, adding chitosan into a mixed solution, uniformly mixing, adding an aminated lignocellulose-aqueous solution and a glutaraldehyde aqueous solution, uniformly mixing, adjusting the pH value to 6.5-7, reacting at 40-45 DEG C for 2.5-3 hours, washing and drying to obtain modified lignocellulose; step 2: (1) uniformly mixing modified polylactic acid, polyhydroxyalkanoate, modified wood fiber, tributyl citrate and triglyceride, banburying, discharging and crushing to obtain composite master batch; and (2) sequentially carrying out extrusion molding, cooling shaping and cutting on the composite master batch to obtain the degradable polylactic acid straw.

The invention discloses a sixteen-hole multifunctional polyester staple fiber and a preparation method thereof, and relates to the technical field of functional fibers. Sodium alginate is used as a skin layer, polyethylene glycol terephthalate is used as a core layer, functional layering is achieved through skin-core compounding, and the interface bonding force between sodium alginate and polyethylene glycol terephthalate is enhanced through glutaraldehyde; in the melting processing process of polyethylene glycol terephthalate, a chain extender is used for reducing the melting point of the polyethylene glycol terephthalate so as to reduce the pyrolysis risk of sodium alginate, meanwhile, a low-polarity lubricant is used for grafting zirconium carbide so as to balance the lubrication and enhancement functions and realize far infrared and antistatic properties, and then an aniline monomer is initiated to polymerize on the surface of zirconium carbide so as to prepare the far infrared anti-static polyethylene glycol terephthalate composite material. Seaweed-carbon can generate far infrared radiation and negative ions, and zirconium carbide can be used as an electron acceptor to enhance the carrier mobility, so that the far infrared and antistatic properties of the fiber are enhanced.

The invention discloses a moisture-proof and pressure-resistant packaging carton and a preparation method thereof, and relates to the technical field of packaging cartons, the structure of the moisture-proof and pressure-resistant packaging carton is sequentially provided with an outer lining, a corrugated core paperboard and an inner lining from top to bottom, and the outer lining, a corrugated core and the inner lining are bonded through polyvinyl alcohol; soaking the prototype paper in a carboxymethyl cellulose aqueous solution, taking out the prototype paper, soaking the prototype paper in a copper sulfate metal ion solution and an aluminum chloride metal ion solution respectively, and performing hot pressing to obtain lining prototype paper and outer lining prototype paper; the preparation method comprises the following steps: adding polyethyleneimine and methanol into deionized water, uniformly stirring, soaking the outer lining prototype paper into the deionized water, heating to 35-36 DEG C, preserving heat, taking out the outer lining prototype paper, soaking the outer lining prototype paper into the solution A, adding glutaraldehyde, reacting at 25-30 DEG C, taking out the outer lining prototype paper, carrying out vacuum drying for 30-45 minutes, coating the surface of the outer lining prototype paper with the solution B, and carrying out vacuum drying to obtain the outer lining.

The invention relates to the field of biological agents, in particular to a compound probiotic preparation rich in organic selenium and a preparation method of the compound probiotic preparation, and efficient synergistic delivery is achieved through plant micromolecule organic selenium extraction and a multi-layer microemulsion embedding technology. The preparation consists of a core active component, a carrier system and a curcumin compound. The plant micromolecular organic selenium is extracted from cardamine hupingshanesis and high-selenium corn flour through an HLUP technology, and the bioavailability is remarkably improved. A corn protein modified W / O / W microemulsion is adopted as a carrier, an outer layer membrane is stable in an acid environment, and an inner layer accurately releases selenium to small intestines; a protective agent composed of trehalose and glucose inhibits ice crystal damage, and glutaraldehyde crosslinking enhances the mechanical strength of the membrane. Curcumin and selenium synergistically enhance antioxidant and immunomodulatory functions, and promote phagocytic activity of macrophages. The stability and bioavailability bottlenecks of a traditional preparation are broken through, and an innovative scheme is provided for functional food development.

The invention provides a method for preparing lactulose from immobilized beta-galactosidase, and belongs to the technical field of functional sugar preparation.The method comprises the following steps that an immobilized enzyme column is prepared, specifically, macroporous alkalescent styrene anion exchange resin is soaked and washed with an ethanol solution, a NaCl solution, an HCl solution and a NaOH solution in sequence; the pretreated resin and beta-galactosidase liquid are mixed, a buffer solution is added, shaking table adsorption is performed, and standing is performed after adsorption; adding a glutaraldehyde solution for cross-linking, and discarding the supernatant to obtain an immobilized enzyme column; adding a magnesium ion solution into a mixed solution of lactose and fructose, and then performing conversion through an immobilized enzyme column to obtain a lactulose conversion solution; the lactulose conversion liquid is sequentially subjected to decoloration, ion exchange, vacuum concentration and continuous simulated moving bed chromatographic separation to obtain a lactulose solution, by means of the method, the lactulose conversion rate is larger than or equal to 60%, the lactulose yield is larger than or equal to 92%, the preparation process is simple, and the cost is low.

A 3D printed bone defect repair scaffold loaded with extracellular matrix of mesenchymal stem cells is provided, its preparation method includes: dissolving gelatin, sodium alginate and 58S bioglass in water to obtain a solution, stirring the solution evenly to obtain 3D printing slurry, and performing 3D printing; chemically cross-linking the semi-finished scaffold with a calcium chloride solution, followed by soaking in a glutaraldehyde solution to chemically cross-link, and cleaning and freeze-drying to obtain the 3D printed scaffold; sterilizing the 3D printed scaffold; seeding rBMSC suspension on the sterilized 3D printed scaffold at a concentration of at least 106 cells / well, and culturing rBMSC by using a low glucose DMEM with 10% FBS for 2 weeks; and taking out the scaffold to perform a decellularization treatment, and freeze-drying the decellularized 3D printed scaffold to obtain the 3D printed bone defect repair scaffold loaded with extracellular matrix of mesenchymal stem cells.

The invention discloses a chitosan modified attapulgite composite material for sewage treatment as well as a preparation method and application thereof, and relates to the technical field of chitosan modified composite materials and sewage treatment agents. The chitosan modified attapulgite composite material is obtained by loading a glutaraldehyde cross-linked sulfonated chitosan-starch copolymer on the surface of attapulgite. In the preparation process of the glutaraldehyde cross-linked sulfonated chitosan-starch copolymer, sulfonated chitosan is firstly prepared, then the sulfonated chitosan is cross-linked by glutaraldehyde, and then the sulfonated chitosan is cross-linked with hydroxyethyl starch to obtain the glutaraldehyde cross-linked sulfonated chitosan-starch copolymer. The chitosan modified attapulgite composite material for sewage treatment has a good flocculation effect on impurities in sewage, can effectively adsorb heavy metal impurities in the sewage, has excellent low-temperature resistance, can effectively precipitate sediment particles in river sewage, and can be used for treating the sewage. And high sewage treatment efficiency can also be ensured in a low-temperature environment.

The invention relates to the technical field of biology, in particular to a sample preservation solution for vagina micro-ecology detection and a preparation method of the sample preservation solution. The invention relates to a sample preservation solution for vaginal micro-ecology detection. The sample preservation solution comprises the following components in percentage by mass: 0.5-0.9% of paraformaldehyde, 0.08-0.12% of glutaraldehyde, 10-18% of a buffer solution, 0.1-0.4% of inositol, 1-10% of a stabilizer, 0.8-5% of a cell treatment agent and the balance of water, the stabilizing agent is prepared from sodium alginate, tween-20 and beta-cyclodextrin. The invention aims to solve the problems of high false negative and false positive rate or difficulty in interpretation caused by liquid-based cell accumulation, unstable subsequent dyeing and decoloration time and the like of a cell preservation solution in the prior art, so that the sample preservation solution for sample cells can keep the forms of cells, protozoa and the like unchanged, and ensures that gram staining negative and positive properties of bacteria and fungi are not changed. The staining and decoloring are relatively stable, the false negative and false positive rate of sample cell detection is effectively reduced, and the sample cell lesion detection and judgment are more accurate.

The invention provides a microbial slow-release porous composite material for sewage treatment as well as a preparation method and application thereof. The preparation method comprises the following steps: dropwise adding an organic ligand solution into a precursor solution consisting of a nanocellulose solution and a cobalt source solution; mixing the reaction solution with polyvinyl alcohol, injecting the mixture into a mold, and performing directional freezing to obtain an aerogel matrix; carrying out hydrophobic modification on the aerogel matrix to obtain a modified aerogel matrix; mixing the microbial suspension with sodium alginate, and homogenizing at high pressure to obtain a gel precursor emulsion; the preparation method comprises the following steps: dropwise adding a calcium chloride solution to gelatinize to obtain gel particles, and then cross-linking and drying by glutaraldehyde to obtain sustained-release capsule particles; dispersing the sustained-release capsule particles in deionized water to obtain dispersion liquid; and dipping the modified aerogel matrix in the dispersion liquid. An aerogel matrix with a hierarchical porous structure is compounded with a sustained-release capsule with a pH response mechanism, so that physical adsorption, chemical catalysis and biodegradation for sewage treatment are realized.

The invention relates to the technical field of thickening agents, in particular to a thickening agent for fracturing fluid and a preparation method of the thickening agent, the thickening agent comprises a liquid material and a solid material, the mass ratio of the liquid material to the solid material is 1: (2.2-2.4), and the liquid material is composed of deionized water and N-methyl pyrrolidone. According to the preparation method disclosed by the invention, the konjaku flour is added in the preparation of the thickening agent, and after the konjaku flour is subjected to mixing reaction and curing treatment, amino functional groups in konjaku molecules can be subjected to cross-linking reaction with aldehyde groups of glutaraldehyde, so that water molecules are wrapped in a cross-linked network structure, and the internal friction force during fluid flowing is increased; and hydroxyl groups on molecular chains of the konjac glucomannan and aldehyde groups of glutaraldehyde are subjected to a condensation reaction to form covalent bonds, so that a cross-linking effect is achieved, a stable chemical cross-linked network structure is formed among the molecular chains of the konjac glucomannan, and the cross-linking performance of the thickening agent is effectively improved.

The invention relates to the technical field of fertilizers, and discloses a slow-release coated fertilizer and a preparation method thereof. Comprising the following raw materials in parts by weight: 57 to 77.6 parts of urea, 14.25 to 24.25 parts of diammonium phosphate, 0 to 5 parts of calcium superphosphate, 4.75 to 14.55 parts of potassium chloride, 0.03 to 0.2 part of chitosan, 0.0075 to 0.05 part of nano silicon dioxide, 0.001 to 0.015 part of glutaraldehyde, 2.96 to 4.94 parts of deionized water, 0.01 to 0.1 part of bacillus subtilis, 0.05 to 0.2 part of mesoporous silicon dioxide loaded nano selenium and 0.5 to 1 part of potassium fulvate. Chitosan, nano silicon dioxide and glutaraldehyde are matched with one another, and chitosan has pH responsiveness, so that the problems that a coating layer of a traditional slow-release fertilizer is prone to being affected by the environment and broken in advance, nutrients are rapidly released, and the slow-release effect is reduced are solved.