358results about How to "Easy reunion" patented technology

The invention discloses a water-retaining controlled-release fertilizer and a preparation method thereof, and relates to the technical field of controlled-release fertilizers. According to the invention, the attapulgite is modified by a phosphoric acid solution, so that the surface of the attapulgite has acidic groups, and the groups can be adsorbed with positive ions in the fertilizer, so that nutrients are adsorbed and fixed on the surface of the attapulgite, and the speed of releasing the fertilizer nutrients into a soil solution is delayed; meanwhile, the modified attapulgite and some nutritional ingredients in the fertilizer can form indissolvable compounds, so that the nutrients are slowly released along with gradual dissolution of the compounds, and the fertilizer efficiency of the fertilizer is prolonged; when the modified attapulgite encounters water, the entering speed of water can be effectively slowed down, dissolution of nutrients in fertilizer particles is controlled, and then the slow and controlled release effect is achieved; and the modified attapulgite can regulate the pH value of the soil, so that the soil environment is more suitable for plant growth and slow release of fertilizer nutrients.

The invention discloses a preparation method of antibacterial warm-keeping graphene quantum dot cloud velvet, and relates to the technical field of cloud velvet. Single-layer graphene is prepared through a chemical method, then single-layer graphene quantum dots are prepared through an electrochemical reaction, the size reaches the nanometer level, the single-layer structure is sharper, and the sterilization effect can be improved; modification enables the surface to be rich in carboxyl and to be attached to cellulose to improve the agglomeration problem; secondly, breaking intermolecular hydrogen bonds of cellulose macromolecules by utilizing the strong action of ball milling and a polar solvent rich in hydroxyl and combining ultrasonic waves; then, the cellulose is combined with hydroxyl cardanol with a side chain containing a hydroxyl group, and cooperates with graphene quantum dots attached to the cellulose for efficient catalysis to generate active oxygen, so that the sterilization effect is achieved; then the modified nanocellulose is prepared into aerogel, and the aerogel is added into polyester as antibacterial master batch to prepare the cloud velvet, so that the warm keeping effect is improved. The cloud velvet prepared by the invention has antibacterial and warm-keeping effects.

The invention relates to a polymer-based composite solid electrolyte, a preparation method and a sodium solid-state battery, and belongs to the technical field of solid-state batteries. The polymer-based composite solid electrolyte is prepared from the following components in parts by mass: 8 to 12 parts of alkene polymer, 4 to 8 parts of sodium salt and 1 to 8 parts of filler, and the filler is nitrided nano TiO2. The polymer-based composite solid electrolyte can be prepared in a simple and efficient mode, the ionic conductivity is high, the electrochemical stability window is wide, the ionic conductivity reaches 0.3-1.2 mS / cm, and the electrochemical stability window reaches 4.3-5.5 V; and meanwhile, the formation of good SEI can be promoted in the sodium solid-state battery, and the interface stability between the electrolyte and the electrode is improved.

The invention relates to the technical field of carbon nanotube materials, in particular to high-dispersity carbon nanotube slurry and a preparation method thereof. Ammonium chloride, sodium azide, novolac epoxy resin and carbon nanotubes are added for modification treatment, and the modified carbon nanotubes are obtained. Then, a silane coupling agent KH550, an MXene material, a palmitic acid solution, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are added and mixed, and the modified MXene material is obtained. And performing ultrasonic dispersion on polyvinylpyrrolidone, N-methyl pyrrolidone, the modified carbon nanotubes and the modified MXene material to obtain the composite conductive filler. The finished product is obtained by adding the surfactant, the deionized water and the composite conductive filler. The finished product prepared by the method has good conductivity and dispersity, so that the finished product has a wide application prospect in the technical field of carbon nanotube materials.

The invention relates to the technical field of cutter manufacturing, in particular to a high-strength and high-toughness ceramic cutter and a preparation method thereof. The metal ions are loaded on the boron nitride nanosheets, the agglomeration phenomenon of the boron nitride nanosheets can be improved through loading of the metal ions, the interaction force between the boron nitride nanosheets is enhanced, and therefore the mechanical strength of boron nitride is improved. According to the preparation method disclosed by the invention, a complex with adhesion is formed on a boron nitride nanosheet by utilizing the chelation of tannic acid and iron ions, and boron nitride loaded with the iron ions and modified hydrotalcite are adhered together by utilizing the adhesion of the complex. The prepared modified soybean protein has a large number of amino groups, the boron nitride-hydrotalcite compound with the amino groups has better compatibility with a modified soybean protein binder, the dispersity of the boron nitride-hydrotalcite compound in a matrix is improved, and the strength and toughness of the ceramic cutting tool are improved.

The invention discloses a catalyst layer for a fuel cell and a preparation method thereof, the catalyst layer comprises an anode catalyst and a cathode catalyst, the anode catalyst layer comprises a Pt-C catalyst, high dielectric micromolecular alcohol, sulfonated lignin doped conductive polymer nanoparticles, a hydrophilic adhesive, an ionomer solution and deionized water; the cathode catalyst layer comprises a catalyst, an ionomer solution, high-dielectric micromolecular alcohol, polytetrafluoroethylene and deionized water; the technical problems that an existing catalyst layer for a fuel cell is poor in water management effect, and an adopted water management material is poor in conductivity can be solved. The preparation method is simple and convenient, and the preparation difficulty and the operation difficulty of operators are greatly reduced.

The invention discloses an anti-aging asphalt-based material and a preparation method thereof, and belongs to the technical field of asphalt material preparation, and the anti-aging asphalt-based material comprises the following raw materials in parts by mass: 100 parts of matrix asphalt and 2-10 parts of an organized zirconium phosphate modifier. Zirconium phosphate is subjected to intercalation treatment through organic molecules, the interlayer spacing of the zirconium phosphate is enlarged, agglomeration of zirconium phosphate particles can be effectively avoided, the compatibility of the zirconium phosphate particles and asphalt is improved, and the ultraviolet absorption performance of the zirconium phosphate particles can be greatly improved; the ultraviolet aging resistance of the obtained modified asphalt can be further effectively improved.

The present application relates to the field of ABL aluminum-plastic composite sheets, and more specifically, it relates to an ultra-high barrier EVOH aluminum-plated composite sheet and a preparation method thereof. An ultra-high barrier EVOH aluminum-plated composite sheet comprises an outer film, a first adhesive layer, a barrier layer, a second adhesive layer, and an inner film fixedly arranged in sequence; the barrier layer is made of an aluminum-plated EVOH film, the aluminum-plated EVOH film comprises an EVOH film layer and an aluminum layer covering the surface of the EVOH film layer, and the EVOH film layer is prepared from a modified EVOH material, and the modified EVOH material comprises the following components in terms of the mass percentage of the modified EVOH material: 2‑8% muscovite, 1‑5% quartz powder, 1‑5% feldspar powder, 0.1‑0.5% coupling agent, and EVOH supplements the remainder. The composite sheet of the present application has a significant barrier effect on water and oxygen, and has good mechanical properties.

The invention discloses a corrosion-resistant cavitation-erosion-resistant self-repairing marine protective coating suitable for a high-temperature environment and a preparation method thereof, belongs to the technical field of marine protective coatings, and aims to further improve the comprehensive performance of existing self-repairing polyurethane. FA-FGE diol is used as a chain extender, and on the basis of a DA bond, the corrosion-resistant cavitation-erosion-resistant self-repairing marine protective coating suitable for the high-temperature environment and the preparation method of the corrosion-resistant cavitation-erosion-resistant self-repairing marine protective coating are prepared. A hydrogen bond is used as a supplement to adjust the content of a chain extender according to different molar ratios, and is introduced into a PU system to obtain self-repairing performance. The dopamine is used for performing surface modification on the carbon nano tube, so that the binding property and the dispersity of the dopamine modified carbon nano tube and a polyurethane interface are improved, and the overall protection performance of the material is improved. Tests show that the material toughness of the coating can reach 356 MJ / m < 3 >, and the tensile strength can reach 72 MPa. Compared with previous reports, the corrosion resistance and cavitation erosion resistance are remarkably improved, the self-healing rate under infrared light for 90 s is 93%, and the self-healing rate after repeating for 3 times is 81%.

The embodiment of the invention relates to a solid electrolyte coated with an artificial SEI membrane on the surface, a preparation method thereof and a solid-state battery, the solid electrolyte coated with the artificial SEI membrane on the surface comprises a solid electrolyte and the artificial SEI membrane coating the solid electrolyte, the solid electrolyte comprises a sulfide solid electrolyte, the artificial SEI membrane comprises a first coating layer and a second coating layer, the first coating layer is located between the solid electrolyte and the second coating layer, the first coating layer comprises lithium fluoride, and the second coating layer comprises lithium fluoride and lithium carbonate. Therefore, the stability and ionic conductivity of the solid electrolyte coated with the artificial SEI film on the surface can be improved.

The invention discloses a ganoderma lucidum extraction method based on a reusable magnetic enzyme. The ganoderma lucidum extraction method comprises the following steps: S1, preparing a nanoscale amination modified Fe3O4-SiO2 magnetic composite carrier; s2, on the basis of the amination modified Fe3O4-SiO2 magnetic composite carrier, cellulase is added, and a magnetic immobilized enzyme buffer solution is obtained; s3, the ganoderma lucidum sporocarp is put into a magnetic immobilized enzyme buffer solution to be subjected to enzymolysis, extraction and filtration, effective components of ganoderma lucidum are obtained, and magnetic immobilized enzyme is recycled for repeated utilization; according to the method, the magnetic nanoparticles are modified, so that the surfaces of the magnetic nanoparticles have specific active groups, meanwhile, the magnetic response advantage of an inorganic magnetic material is reserved, the nanoscale amination-modified Fe3O4-SiO2 magnetic composite carrier is prepared, enzyme molecules can be directly anchored on the surfaces of the magnetic nanoparticles, and enzyme activity is improved. The immobilized enzyme can be conveniently recycled from a reaction system, so that the cost of an enzyme preparation can be reduced, and the enzyme activity stability can be improved.

The invention provides a preparation method of high-specific-surface-area silver particles for low-temperature sintered silver paste, and belongs to the technical field of conductive materials, and the preparation method comprises the following steps: adding ammonia water into a hydrazine hydrate solution with the molar concentration of 1.60-6.0 mol / L until the pH value of the hydrazine hydrate solution is 10-13; the method comprises the following steps: preparing an alpha-amino acid aqueous solution with the molar concentration of 0.012-0.048 mol / L at the temperature of 35-45 DEG C; the preparation method comprises the following steps: dropwise adding a hydrazine hydrate solution and a silver nitrate solution into an alpha-amino acid solution at the same time within 8-12min, stirring, heating, adding a sodium hydroxide solution to adjust the pH value of a reaction solution to 11-13, continuously stirring, aging, separating, washing and drying to obtain the silver particles with high specific surface area. On the premise of ensuring the conductivity of the high-specific-surface-area silver particles, the particle size and the specific surface area of the silver particles are controllable, the requirement for the stability of the silver powder serving as the conductive filler is met, and the yield is high.

The invention discloses a preparation method of a rod-like selenium nano-carrier, and belongs to the technical field of nano-pesticides. The rod-like selenium nano-carrier is formed by converting chitosan modified amorphous selenium (a-Se) into single crystal ash selenium (t-Se). The amorphous selenium is initially spherical, and after chitosan modification, the spherical amorphous selenium is converted into single crystal ash rod-shaped selenium nanoparticles. The length of the rod-like selenium nano-carrier is 590-610 nm, the diameter of the rod-like selenium nano-carrier is 20-25 nm, the effective average particle size of the rod-like selenium nano-carrier is 90-110 nm, the drug loading rate is 39.28% + / -2%, and the encapsulation efficiency is 64.90% + / -3%. In addition, the invention also provides an application of the rod-like selenium nano-carrier in a nano bactericide material.

The invention relates to the technical field of electrochemical analysis and detection, in particular to a preparation method of a nano composite material containing manganese-zirconium-based MOFs confinement zero-valent iron and a construction method for constructing an electrochemical sensor by using the nano composite material. A preparation method of a nano composite material containing manganese-zirconium-based MOFs confinement zero-valent iron comprises the following steps: dissolving a PCN-222 (Mn) precursor in DMF for ultrasonic treatment, stirring and heating a suspension I after ultrasonic treatment, adding Fe (NO3) 2 and p-aminobenzoic acid, continuously stirring, filtering and drying, then transferring into ethylene glycol, dropwise adding NaBH4 for reaction, filtering, washing, and drying to obtain the nano composite material containing manganese-zirconium-based MOFs confinement zero-valent iron. A third suspension is obtained. And centrifuging the suspension III to obtain a solid II, washing the solid II with an acetone solution, and drying. The prepared manganese-zirconium-based MOFs confinement zero-valent iron nano material can be used for modifying an electrode and constructing an electrochemical sensor, and the constructed electrochemical sensor can effectively detect trace Hg < 2 + > in a water environment, and has high sensitivity and good stability on Hg < 2 + > electrochemical detection.

The invention discloses an ultra-fine grinding thinning grinding wheel and a preparation method thereof.The grinding wheel comprises a grinding wheel base body and tool bit assemblies, a plurality of reserved grooves are formed in the circumferential direction of the grinding wheel base body at equal intervals, and the tool bit assemblies are arranged in the reserved grooves; the tool bit assembly comprises, by volume fraction, 35%-45% of composite abrasive micro powder, 30%-45% of a ceramic bonding agent, 20%-30% of a double-effect pore forming agent, 1%-3% of a filling agent, 1%-2% of a dispersing agent and a temporary bonding agent accounting for 5% of the total weight. Through design optimization of the grinding wheel formula and the preparation method, the better wafer surface quality can be obtained under the ultra-fine grinding and thinning process, and meanwhile, the stability and the long service life of the grinding wheel in the service process are guaranteed; and a composite abrasive material combination and a double-effect pore-forming agent are matched and optimized, so that the optimized superfine abrasive material combination obtains a high-quality grinding and thinning surface, and meanwhile, the stable and long-acting service life is considered.

The invention belongs to the technical field of high polymer materials, and particularly relates to a graphene nano composite material and a preparation method thereof. The graphene nano composite material is prepared from the following components: graphite powder, APTES (Aminopropyltriethoxysilane), polyvinyl alcohol, nano TiO2, polyethylene glycol dihydric alcohol, trimethylolpropane and isocyanate. The specific preparation steps of the graphene nano composite material are as follows: S1: preparation of graphene oxide; s2, introducing an amino silane group into the graphene oxide; s3, grafting polyvinyl alcohol and nano titanium dioxide; s4, carrying out in-situ polymerization grafting on the modified graphene oxide and polyurethane polyol to obtain a graphene nano composite material; according to the preparation method, the dispersity of graphene in a polyurethane matrix is enhanced through APTES functionalization and PVA grafting, and agglomeration is prevented; the APTES and the polyurethane form a covalent bond, so that the interface bonding is enhanced; pVA increases steric hindrance and improves toughness; tiO2 nanoparticles are stably dispersed, so that the impact resistance and the tensile strength are improved.

The invention provides a device and a method for improving transparency of a natural water body by utilizing a microalgae biological membrane, and belongs to the field of water treatment, and the device comprises a water tank, rollers, a microalgae attachment matrix, a water distribution device and a lighting device. The transparency of the natural water body is effectively improved through the microalgae biological membrane. The microalgae biological membrane secretes macromolecular extracellular polymeric substances, can adsorb suspended particulate matters and soluble organic matters in water, and inhibits the reproduction of other planktons through nutrition competition, so that the turbidity is reduced. In addition, the device is designed as up-flow water inlet, so that the contact between the water body and the microalgae biological membrane is enhanced, and the treatment effect is improved. LED lamps and a heating device are adopted to keep a proper growth environment, and meanwhile, a photovoltaic power generation system is arranged, so that green and environment-friendly effects are achieved. The method is simple and easy to implement, low in cost and convenient to manage and maintain, and a novel and effective technical scheme is provided for improving the transparency of the natural water body.

The invention provides a preparation method of modified nano silicon powder wrapped by a polymer, which comprises the following steps: dissolving a polymer PVDF (Polyvinylidene Fluoride) in an organic solvent N-dimethylformamide DMF (Dimethyl Formamide), carrying out ultrasonic treatment, adding Si powder, adding the Si powder in three times, and then carrying out magnetic stirring, so that nano metal powder and a polymer solution are fully mixed; the preparation method comprises the following steps: adding an energetic oxidant AP into a polymer solution containing nano Si powder according to a mass ratio of PVDF / AP of 1: 3, magnetically stirring, and carrying out ultrasonic treatment to obtain a precursor solution PVDF / AP / Si; and relevant parameters are set, and the coated and modified shell-core type nano composite metal powder is prepared through a spray granulation method. According to the invention, the yield of the silicon-based compound can be improved, the energy and combustion performance of the compound are improved, and the cost of coating silicon powder is effectively reduced. In addition, the PVDF, the AP and the silicon powder are wrapped according to the optimal proportion, so that the energy release efficiency of the compound Si-coated PVDF / AP reaches the maximum.

The invention provides a flexible conductive composite material and a preparation method and application thereof, and belongs to the technical field of high polymer materials, and the preparation method comprises the following steps: mixing graphene, carbon nanotubes and a polar organic solvent to obtain a nano carbon material dispersion liquid; mixing raw silicone rubber, a silane coupling agent and the nano carbon material dispersion liquid, and carrying out surface modification treatment to obtain a nano carbon modified raw rubber mixed liquid; and mixing the nanocarbon modified raw rubber mixed solution with a cross-linking agent, and carrying out a cross-linking reaction to obtain the flexible conductive composite material. The prepared flexible conductive composite material has a low seepage threshold value and high mechanical performance, and after the flexible conductive composite material serves as a sensing layer of the flexible piezoresistive sensor, the flexible piezoresistive sensor can have a large measuring range and high sensitivity and repeated loading capacity.

The invention provides a high-entropy hard alloy and a preparation method and application thereof.The preparation method comprises the steps that the particle surface of hard phase powder is coated with a binding phase metal layer, then forming, degreasing and vacuum presintering are conducted, and a presintered body with the relative density not exceeding 90% is obtained; the surface of the pre-sintered body is coated with at least two metal layers, and then the high-entropy hard alloy is obtained through vacuum sintering and hot isostatic pressing infiltration treatment; the at least two metal layers comprise an innermost high-entropy alloy layer and an outermost metal layer. Through the arrangement of the binding phase metal layer, the damage of carbon, nitrogen, boron or silicon in the hard phase powder to the crystal structure of the high-entropy alloy is prevented; and in cooperation with subsequent hot isostatic pressing infiltration treatment, the problem that a binding phase of the high-entropy alloy is prone to agglomeration due to a traditional powder mixing method is solved, and meanwhile the problems that infiltration is not thorough and is limited by the appearance and size of a product are solved.

The invention relates to the technical field of new materials, and discloses a flame-retardant modified halloysite grafted waterborne polyurethane material, three flame-retardant elements N, P and S are introduced to the surface of halloysite, so that the obtained waterborne polyurethane material has excellent flame-retardant property, the surface of a halloysite tube is organically modified, and the flame-retardant property of the halloysite tube is improved. The self-agglomeration of the halloysite nanotubes can be effectively inhibited, and meanwhile, the halloysite enables a polyurethane molecular chain to be grafted on the halloysite in situ through the terminated hydroxyl, so that the dispersity of the halloysite in a polyurethane matrix can be effectively enhanced, a cross-linking center is formed, the compatibility of the polyurethane and the halloysite at a molecular level is achieved, and the self-agglomeration of the halloysite nanotubes can be effectively inhibited. The halloysite is added, so that the microphase separation structure of the composite material is influenced, the mechanical property of polyurethane is improved, the halloysite with high length-diameter ratio can effectively limit the movement of a polyurethane molecular chain, and the thermal stability of the composite material is improved.

The invention relates to bacillus for soil microbial film sand stabilization, a microbial agent containing the bacillus and application of the bacillus. The microbial agent is prepared by screening strains which survive in local aeolian sandy soil and are high in exopolysaccharide yield and optional auxiliary strains and matching with proper culture media and adsorbents. After the microbial agent is applied to soil needing sand stabilization treatment, the bacillus secretes exopolysaccharides, so that bacterial colonies are continuously adhered together to form a stable microbial film, a relatively stable special space structure is formed between the microbial film and soil particles, soil agglomeration is promoted, and a remarkable sand stabilization effect can be achieved. The method can effectively improve the characteristics and moisture characteristics of the aeolian sandy soil, has a good promotion effect on the growth and development of psammophyte, has great application potential and application value in the improvement of the aeolian sandy soil, is simple to operate and low in cost, and can provide a new way for the prevention and treatment of land desertification.

The invention discloses a modified multi-walled carbon nanotube, a flame-retardant PET (Polyethylene Terephthalate) material and a preparation method of the flame-retardant PET material. The preparation method of the modified multi-walled carbon nanotube comprises the following steps: S1, mixing a multi-walled carbon nanotube with mixed acid, carrying out ultrasonic oscillation for 15-25 minutes, refluxing for 1-2 hours, diluting with distilled water, filtering, and washing with water until filtrate is neutral; and S2, mixing the product in the step S1 with the mixed solution, refluxing for 1-2 hours, diluting with distilled water, filtering, washing with water until the filtrate is neutral, and drying the filter cake to obtain the modified multi-walled carbon nanotube. According to the prepared modified multi-walled carbon nanotube, the surface carboxyl grafting rate is greatly increased while the structure is maintained. When the flame retardant is applied to a flame-retardant PET material, the flame retardant property and the mechanical property of the PET material can be remarkably improved.

The invention relates to the technical field of environmental engineering, in particular to a fluorine ion crystallization recovery method based on a PCR (polymerase chain reaction) pellet reactor, which comprises the following steps: (1) measuring and recording the concentration of fluorine ions in wastewater to be treated, and adding a calcium salt agent and a special seed crystal according to the concentration of the fluorine ions in the wastewater to be treated; (2) adding a calcium salt agent and a special seed crystal, uniformly stirring and mixing, and adjusting the pH value of the wastewater to 6.0-7.5; (3) controlling the reaction time to be 10-30 minutes; (4) recycling fluorine-containing pellet crystals after the wastewater treatment is completed; the invention provides a fluorine ion crystallization recovery method based on a PCR (polymerase chain reaction) pellet reactor, which comprises the following steps: adding a calcium-containing composite chemical agent and a seed crystal into fluorine-containing wastewater to induce fluorine element crystallization to form microcrystals, and crystallizing layer by layer to form a fluorite-like layer as time goes on so as to realize recovery and reutilization of fluorine resources.

The invention discloses a molybdenum disulfide nanoflower composite material loaded with copper particles as well as a preparation method and application of the molybdenum disulfide nanoflower composite material. The preparation method of the composite material comprises the following steps: firstly, preparing a molybdenum disulfide material with a three-dimensional flower-shaped structure through a hydrothermal method; ultrasonically dispersing the molybdenum disulfide material in water, mixing with a copper ion solution in a corresponding proportion, performing ultrasonic treatment, transferring into a photoreactor, keeping an anaerobic condition through nitrogen bubbling under illumination and stirring, injecting a reducing solution, performing photodeposition reaction to anchor nano-scale copper particles to the surface of the molybdenum disulfide material, and preparing the molybdenum disulfide material. The molybdenum disulfide nanoflower composite material with the three-dimensional structure and loaded with the copper particles is obtained. The composite material prepared by the invention is good in stability, can be applied to the field of sterilization, has a remarkable sterilization effect on escherichia coli, staphylococcus aureus and pseudomonas aeruginosa, and has a good application prospect, and the catalyst is not easy to lose and can be recycled.

The invention belongs to the technical field of high-voltage electric appliance material preparation, and particularly relates to a zinc oxide resistor disc and a preparation method and application thereof. The preparation method comprises the following steps: (1) pre-sintering zinc oxide powder; (2) mixing the zinc oxide powder obtained in the step (1), an auxiliary agent and a dispersion liquid, and carrying out ball milling to obtain slurry; the particle size D50 of the slurry is 0.8-1.2 [mu] m, and the dispersity is greater than or equal to 95%; (3) performing spray drying and granulation on the slurry to obtain granulation powder; (4) carrying out molding and first sintering on the granulated powder to obtain a resistor disc semi-finished product; the first sintering adopts sectional sintering; and (5) forming an electrode layer on at least one surface of the resistor disc semi-finished product by adopting a vacuum sputtering and / or electrophoretic deposition process, and performing secondary sintering and annealing. The contact resistance of the zinc oxide resistor disc is less than or equal to 5m omega; and after 1000 hours of aging in a 85 DEG C + 85% RH environment, the leakage current increase is less than or equal to 2 [mu] A, and the performance degradation rate is less than or equal to 5%.

The invention relates to a preparation method and application of poly (D-mannose) nano-selenium, explores the potential of the poly (D-mannose) nano-selenium in inhibiting the activity of various common food-borne pathogenic bacteria and the formation of biofilms, and provides scientific basis and technical support for the application of the poly (D-mannose) nano-selenium in the fields of food preservation and food safety. The preparation method comprises the following steps: 1) uniformly mixing a poly D-mannose solution and a sodium selenite solution at a certain speed to form a mixed solution; 2) slowly dropwise adding an ascorbic acid solution into the mixed solution prepared in the step 1) to promote generation of poly D-mannose-selenium nanoparticles; (3) carrying out dialysis treatment, so as to obtain pure poly D-mannose-selenium nanoparticles; the poly D-mannose-selenium nano-particles prepared by the invention have remarkable inhibitory activity on various food-borne pathogenic bacteria, particularly have a remarkable inhibitory effect on formation of biofilms of staphylococcus aureus and bacillus cereus, and are innovations on the preparation method and application of the poly D-mannose nano-selenium.

The invention relates to the technical field of PVC (polyvinyl chloride), and discloses a high-toughness PVC composite material and application thereof in corrugated soft leather. 5-hydroxyisophthalaldehyde, silane coupling agent modified nano silicon dioxide, diethylenetriamine, dimethyl phosphite and the like are used as raw materials, phosphorus-containing benzoxazine-based nano silicon dioxide is prepared through reaction, and the high-toughness PVC composite material is used for preparing corrugated soft leather. And adding the mixture into PVC, and uniformly mixing to obtain the high-toughness PVC composite material. The nano silicon dioxide particles, the rigid benzene ring structure, the six-membered ring structure and the benzoxazine structure are mutually assisted to improve the heat resistance of the PVC composite material. Flame-retardant phosphorus element, nitrogen element and silicon element contained in the PVC composite material are mutually assisted, so that the flame-retardant property of the PVC composite material is jointly improved. Tests prove that the PVC composite material prepared by the invention has relatively good mechanical properties, heat resistance and flame retardance.

The invention relates to a preparation method of a super-hydrophobic composite coating based on magnetically-induced fluorinated graphene, which comprises the following steps: loading magnetic nanoparticles among fluorinated graphene sheets subjected to low-temperature ultrasonic dispersion by adopting a thermal solvent method to obtain a magnetic nanoparticle-fluorinated graphene composite material; coating the surface of a base material with a coating containing the magnetic nanoparticle-fluorinated graphene composite material, and then applying a directional magnetic field with a certain magnetic field intensity on the coating base material, so that the magnetic nanoparticle-fluorinated graphene composite material is directionally moved to the surface of the coating; the surface of the super-hydrophobic composite coating is provided with a microcosmic rough structure, and the super-hydrophobic composite coating has the characteristic of low surface energy. According to the preparation method, the dispersity of the fluorinated graphene in an organic resin matrix is improved, and the preparation process is simple, environmentally friendly, free of pollution and low in cost and can be used for large-scale production; according to the coating prepared by the preparation method, the corrosion resistance of the coating can be enhanced, multiple functions of hydrophobicity, corrosion prevention, antifouling and the like can be integrated, and the requirements of different application scenes are met.

The present application relates to a kind of in situ low-temperature confined carbonization construction carbon dot enrichment coating layer manganese-based positive electrode material and its preparation method, by accurately coordinating the evolution condition of carbon point carbon source in the mixing system environment of coating process, freezing condition and sublimation and carbonization, realize the whole process synergistic control of carbon point carbon source spatial distribution, ice crystal template state, skeleton construction of controlled conversion of carbon point carbon source and harmful residue removal on the surface of manganese-based positive electrode material, successfully constructed the carbon dot enrichment coating layer of size controllable, density adjustable, ion permeability good and interface combination firm on the surface of manganese-based positive electrode material, to realize the synergistic promotion of manganese-based positive electrode material cycle performance, rate performance and interface stability.