459 results about "Composite nanoparticles" patented technology

The invention discloses a flexible PI heat-conducting insulating film pad and a preparation method thereof, and relates to the field of film pads. The preparation method comprises the following steps: preparing Fe3O4 magnetic heat-conducting core and SiO2 insulating shell composite nanoparticles by a sol-gel method, treating and grafting epoxy groups by a silane coupling agent, performing ring-opening addition with one end amino group of amino-terminated polydimethylsiloxane, and reacting the other end amino group with polyethylene glycol diglycidyl ether, so that two flexible long chains are grafted on SiO2. Due to the modified composite nanoparticles and the flexible long-chain structure, the flexibility of the film pad is remarkably improved; thermal vibration of silicon-oxygen bonds and ether bonds promotes heat transfer, a hydrogen bond network is formed with a PI substrate to improve dispersion stability, particles are orderly arranged under the action of a high-frequency magnetic field to construct a three-dimensional heat conduction network, and heat conduction efficiency is enhanced; the SiO2 isolates the inner core from conducting and improves the insulating property of the film pad by virtue of good insulativity and no free charge in the flexible long-chain polymer. The flexible PI heat-conducting insulating film pad prepared by the invention has the effects of flexibility, heat conduction and insulation.

The invention relates to the technical field of food processing, and discloses casein-tea polysaccharide-polyphenol composite nanoparticles and a preparation method of the casein-tea polysaccharide-polyphenol composite nanoparticles, and the preparation method comprises the following steps: mixing large yellow tea polysaccharide with a casein solution to obtain a CS / TPS mixed solution; performing glycosylation modification on casein in the CS / TPS mixed solution by adopting a Maillard reaction to prepare a casein-polysaccharide copolymer solution; the preparation method comprises the following steps: mixing a plurality of catechins, dissolving the catechins in ultrapure water to obtain a mixture stock solution, mixing the mixture stock solution and a casein-polysaccharide copolymer solution according to a volume ratio of 1: 16, stirring for 1 hour for self-assembly, pre-freezing the stirred solution at-80 DEG C, and freeze-drying for 48 hours to obtain CS-TPS-MIX nano-composite powder. According to the invention, a polyphenol delivery system with a dual antioxidant synergistic mechanism is constructed through a Maillard reaction mediated nano-composite technology, and the system is stable in structure, so that the release of polyphenol is more controllable.

The invention discloses a composite lithium supplement agent and a preparation method and application thereof, and belongs to the technical field of lithium ion batteries. The composite lithium supplement agent comprises a porous carbon material and lithium oxalate and lithium carbonate nanoparticles which grow on the surface of porous carbon and in a pore structure in situ. According to the composite lithium supplementing agent provided by the invention, lithium oxalate and lithium carbonate composite nanoparticles uniformly distributed in the porous carbon pore structure are obtained by limiting the growth of lithium oxalate and lithium carbonate through the porous carbon pore structure, so that the decomposition voltage of the composite lithium supplementing agent is greatly reduced, and the total lithium supplementing capacity and the continuous lithium supplementing capacity are improved.

The invention discloses an RGD-click chemical crosslinking siRNA nano-carrier, a preparation method thereof and application of the nano-carrier in preparation of a medicine for treating secondary thyroidism, and belongs to the technical field of medicines.The nano-carrier is RGD-PEG-PLys (N), and the preparation method of the nano-carrier comprises the steps of synthesis of PLys (ss-DBCO), synthesis of RGD-PEG-PLys (N) and the like. According to the application, the nano-carrier is used for preparing siRNA composite nanoparticles; vascular endothelial targeting (RGD), dynamic stability (click crosslinking) and microenvironment responsiveness (disulfide bond) are organically combined for the first time to achieve mutual synergistic interaction, and the effect ceiling of an existing material is broken through; according to the siRNA composite nanoparticle, the silence effect of the PTH gene as long as 70 days can be achieved through single intravenous injection, the PTH inhibition rate is larger than 85%, the siRNA accumulation amount in parathyroid gland tissue is remarkably increased through RGD targeting (8.6 times that of a non-targeting group), the liver and kidney distribution amount is reduced by 60%, and the system toxicity is controllable.

The invention provides a dry powder drag reducer for fracturing fluid and a preparation method of the dry powder drag reducer, and belongs to the technical field of fracturing materials for well drilling, and the preparation method comprises the following steps: dissolving 4-bromobutyryl chloride and N-dodecyl methylamine in acetonitrile, heating and stirring for reaction, adding polyethylene glycol monomethyl ether acrylate and dichloromethane, stirring and purifying in a nitrogen atmosphere to obtain a dry powder drag reducer; a double-tailed hydrophobic monomer is obtained; uniformly mixing the core-shell SiO2 / Fe3O4 composite nanoparticles, an ethanol water solution, KH570 and an ammonia solution, stirring, and purifying to obtain modified SiO2 / Fe3O4; the preparation method comprises the following steps: adding acrylamide, acrylic acid, sodium 2-acrylamido-2-methylpropanesulfonate, a double-tailed hydrophobic monomer and modified SiO2 / Fe3O4 into water, uniformly mixing, adjusting the pH value, introducing nitrogen, mixing and stirring, adding an azo initiator, stirring, cooling, purifying, carrying out vacuum drying, and crushing into powder, thereby obtaining the dry powder drag reducer for the fracturing fluid. The drag reducer has certain heat resistance while achieving good drag reduction performance, and can be better applied to fracturing operation in the well drilling process.

The invention discloses a high-utilization-rate ginseng active ingredient medicinal preparation and a preparation method thereof, and relates to the technical field of medicines. The high-utilization-rate ginseng active ingredient pharmaceutical preparation is prepared from chitosan coated drug-loaded porous silicon dioxide composite nanoparticles and a drug-loaded MIL-101 metal organic framework matrix material, chitosan-coated drug-loading porous silicon dioxide composite nanoparticles are loaded on the surface of a drug-loading MIL-101 metal organic framework base material, and sodium alginate and a chitosan gel material are subjected to cross-linking connection, so that independent coating is formed, the framework base material and the composite nanoparticles are connected into a whole, the encapsulation performance and the drug loading capacity are improved, and the drug-loading capacity of the drug-loading MIL-101 metal organic framework composite nanoparticles is improved. Furthermore, the loading and the loading stability of the ginsenoside are improved, the adverse effects of gastric juice and gastrointestinal peristalsis on the activity of the ginsenoside are effectively reduced, the release and the absorption of the ginsenoside in intestinal tracts are remarkably enhanced, and the bioavailability is relatively high.

The invention discloses a preparation method of a curcumin-loaded Pickering emulsion steady-state carrier and tea protein-chitosan composite nanoparticles used by the curcumin-loaded Pickering emulsion steady-state carrier, and belongs to the technical field of high-valued processing of food functional factors. The preparation method comprises the following steps: firstly, extracting tea protein from a tea leaf processing byproduct tea residue by adopting an alkali extraction and acid precipitation method, and secondly, constructing the tea protein-chitosan composite nanoparticles by adopting a pH induction method. And mixing the oil phase containing curcumin with the water phase, and emulsifying by using a high-speed shearing machine to prepare the Pickering emulsion. The method is simple to operate, the prepared Pickering emulsion stabilized by the tea protein-chitosan composite nanoparticles can improve the bioavailability of curcumin from 10.8% to 32.6%, meanwhile, high-value utilization of the tea protein is achieved, and the method has important significance in promoting development and application of functional food.

The invention discloses an anti-corrosion self-repairing super-amphiphobic coating film and a preparation method thereof, and belongs to the technical field of polymer coating materials. The coating film sequentially comprises a nano particle skeleton layer, a dynamic borate bond layer and a super-amphiphobic functional layer from inside to outside, and the three-layer gradient design synergistically realizes micro / nano structure stability, self-repairing and super-amphiphobic functions. The framework layer takes SiO2-TiO2 composite nanoparticles as a substrate and provides support; the dynamic boric acid ester bond layer forms a dynamic network through polycondensation of an organic boron compound, endows the self-repairing capability and enhances interface bonding; the super-amphiphobic functional layer is formed by grafting a fluorine-containing organosilicon compound and has hydrophobic and oleophobic properties. A multi-layer structure is constructed step by step, the reaction condition is mild, the operation is simple, the cost is low, the method is suitable for large-scale industrial preparation, the coating film has excellent super-amphiphobic performance and interface adhesion performance, the super-amphiphobic performance of the coating film can still be kept stable in long-term use or a complex environment, and the problem that an existing super-amphiphobic material is prone to damage is effectively solved.

The present invention discloses coated hydrophobic polyphenol nanoparticles, preparation method therefor and application thereof. The preparation method for coated hydrophobic polyphenol nanoparticles includes: (1) obtaining a hydrophobic polyphenol nanoparticles suspension; (2) injecting a catechin aqueous solution and a metal salt aqueous solution into the hydrophobic polyphenol nanoparticles suspension to obtain a composite nanoparticles suspension; (3) removing excess catechin and metal ions from the composite nanoparticles suspension to obtain a coated hydrophobic polyphenol nanoparticles suspension. The present invention provides an application of the coated hydrophobic polyphenol nanoparticles in the preparation of pectin gel. The coated hydrophobic polyphenol nanoparticles exhibit significantly enhanced biological activity and long-term stability, developing a pectin gel with long-term stability.

The invention provides a composite nanoparticle with active substance sequential release capability, a multifunctional microneedle patch based on curcumin-loaded ZIF-67 nanoparticles, preparation methods of the composite nanoparticle and the multifunctional microneedle patch and application of the multifunctional microneedle patch, and belongs to the technical field of biology. The composite nano-particles with the active substance sequential release capability are CurZIF-67NPs, the average particle size is 403 + / -7 nm, the microstructure is dodecahedral structure particles with rough textures on the surface, and the composite nano-particles have the effects of slowly releasing bioactive substances, improving the inflammatory microenvironment and regulating and controlling osteogenesis under certain conditions. The composite nano-particle comprises curcumin powder and a ZIF-67 nano-material, the ZIF-67 nano-material can be decomposed to quickly release Co < 2 + >, macrophages are regulated and controlled to be polarized to an M2 type, and excessive immune inflammation reaction is improved; the curcumin powder is slowly released, so that the periodontal ligament stem cells can be regulated and controlled to be differentiated into osteoblasts, and the osteogenic activity is enhanced.

The invention discloses a dual-emission molecular imprinting ratiometric fluorescence sensor, a preparation method thereof and application of the dual-emission molecular imprinting ratiometric fluorescence sensor in aureomycin detection, and belongs to the technical field of chemical sensors. The preparation method of the sensor comprises the following steps: preparing silicon dioxide-quantum dot composite nanoparticles, and preparing a molecularly imprinted polymer by taking salicylamide as a template molecule; and mixing the molecularly imprinted polymer and the silicon dioxide-quantum dot composite nanoparticles in an HEPES buffer solution by adopting a post-mixing strategy to construct the dual-emission molecularly imprinted ratiometric fluorescence sensor. The double-emission molecular imprinting ratiometric fluorescence sensor has the beneficial effects that the double-emission molecular imprinting ratiometric fluorescence sensor provided by the invention is rich in fluorescence color change, rapid, high-sensitivity and visual detection of aureomycin can be realized, the whole detection process is simple, convenient and rapid, and the double-emission molecular imprinting ratiometric fluorescence sensor is suitable for being widely popularized in practical application.

The present disclosure relates to a method for easily preparing niobium-containing titanium-ruthenium composite nanoparticles with excellent stability and electrochemical properties, niobium-containing titanium-ruthenium composite nanoparticles with excellent stability and efficiency, and a chlorine evolution electrode comprising the same.

The embodiment of the invention provides a plastic-coated steel pipe and a plastic coating process thereof, and relates to the technical field of plastic-coated steel pipes. The plastic-coated steel pipe comprises a steel pipe base body, a metal transition layer, an inner anticorrosive coating, a fiber reinforced winding layer and an outer protective coating are sequentially arranged on the outer surface of the steel pipe base body from inside to outside, and the metal transition layer is a nickel-chromium-aluminum-yttrium alloy layer and is formed on the surface of the steel pipe base body through a supersonic plasma spraying process. And the inner anticorrosive coating is formed by a mixture of bisphenol F type epoxy resin and novolac epoxy resin, and is doped with silicon nitride and zirconium oxide composite nanoparticles subjected to surface treatment. By arranging a multi-stage composite structure of the metal transition layer, the high-temperature-resistant anti-corrosion coating, the fiber reinforcement layer and the self-repairing outer layer and arranging the detachable heat insulation sheath, the interface bonding strength, heat resistance, mechanical damage resistance and corrosion resistance of the plastic-coated steel pipe are improved; and the service life of the composite material in high-temperature, strong-corrosion and complex construction environments is effectively prolonged.

The invention relates to the field of nano materials, in particular to a chitosan and recombinant collagen composite nano material as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing chitosan with an acid solution to obtain a chitosan acid solution; mixing the recombinant collagen with a buffer solution to obtain a recombinant collagen buffer solution; dropwise adding the chitosan acid solution into the recombinant collagen buffer solution, so that the chitosan particles and the recombinant collagen particles are self-assembled into composite nanoparticles; the particle size of the composite nanoparticles is smaller than or equal to 300 nm. The chitosan acid solution and the recombinant collagen buffer solution form a stable nanoparticle structure through the self-assembly effect of positive and negative charges, and the problem of toxicity introduced by traditional chemical crosslinking is avoided. The particle size of the composite nanoparticles is less than or equal to 300nm, so that the transdermal efficiency of the collagen is improved; due to the structural characteristics of the nanoparticles, the permeability and the local bioavailability of the medicine are remarkably improved.

The invention discloses a composition containing a polypeptide exosome and application of the composition in preparation of a product with skin repair ability, and particularly relates to the technical field of biology, the composition comprises polypeptide-exosome composite nanoparticles, and a polypeptide containing a GRGDS motif and an umbilical cord Wharton's jelly exosome are covalently crosslinked; the lipid double-layer coating layer comprises phosphatidylcholine, cholesterol and PEG-2000, and the molar ratio of the phosphatidylcholine to the cholesterol to the PEG-2000 is 5: 3: 2; the synergist is prepared from 0.1 to 5 percent of epicatechin gallate and 2 to 8 percent of recombinant collagen III oligopeptide. The nano-liposome is prepared through microfluidic self-assembly and a film hydration-ultrasonic intercalation method, and can be loaded on a degradable microneedle patch, so that targeted slow release of a wound part is realized. Through the synergistic effect of targeted delivery, oxidation resistance and collagen regeneration, the skin repair efficiency is remarkably improved, and the healing time is shortened.

The invention discloses a graphene aerogel modified elastic graphite material and a preparation method thereof, and the graphene aerogel modified elastic graphite material comprises the following components by mass: 50-80 parts of crystalline flake graphite; 8 to 15 parts of graphene aerogel; 3 to 8 parts of aminated modified boron-doped carbon nanotubes; 2 to 6 parts of hydroxyapatite-cerium oxide composite nano particles; 1 to 4 parts of a polyimide-montmorillonite nano composite material; 0.5 to 3 parts of titanate coupling agent modified nano silicon dioxide; 1-3 parts of a dispersant; 2-5 parts of a binder; the amination modified boron-doped carbon nanotubes can enhance the electrical conductivity and interface bonding force of the material, the hydroxyapatite-cerium oxide composite nanoparticles improve the high-temperature stability and mechanical toughness of the material, and the polyimide-montmorillonite nanocomposite improves the corrosion resistance and resilience durability of the material. And the titanate coupling agent modified nano silicon dioxide further optimizes the dispersion uniformity of all the components, and the comprehensive performance of the material is remarkably improved.

The invention discloses a muscle-bone regeneration sustained-release preparation for targeting knee joint cartilage and a preparation process thereof, the preparation is composed of a cartilage targeting peptide modified PLGA-hyaluronic acid composite nanoparticle sustained-release carrier, an active regeneration component, a biocompatible matrix and an anti-inflammatory component, nanoparticles are prepared by a multiple emulsion solvent evaporation method, and targeting peptide is modified; the composite concentrated growth factors, stem cells and traditional Chinese medicine extracts have the functions of targeted enrichment, long-acting slow release, anti-inflammation and cartilage regeneration promotion, and can be used for knee joint cartilage defect repair.

The invention discloses a Pt-based composite nanoparticle catalyst as well as a preparation method and application thereof, the catalyst comprises a V5O12 carrier and Pt nanoparticles loaded on the carrier, and the V5O12 is of a multi-stage layered nanoflower structure; the catalyst is obtained by in-situ generation of Pt nanoparticles on a V5O12 carrier. According to the catalyst disclosed by the invention, the superfine Pt nano-particles are loaded on the metal oxide V5O12, so that the activity and the stability of the catalyst are improved; in addition, the preparation method is simple to operate and low in cost, and large-scale production can be realized.

The invention discloses a drug-loaded protein-phospholipid composite nanoparticle as well as a preparation method and application thereof. The drug-loaded protein-phospholipid composite nanoparticle has a core-shell structure, an inner core comprises silk fibroin and a hydrophilic drug, a shell layer comprises a plurality of phospholipid bimolecular layers which are stacked layer by layer, each phospholipid bimolecular layer comprises soya bean lecithin, a hydrophobic drug is embedded in a hydrophobic region in each phospholipid bimolecular layer, and the hydrophobic drug is embedded in a hydrophobic region in each phospholipid bimolecular layer. Silk fibroin and a hydrophilic drug are embedded in the hydrophilic area, and zein and cholesterol are embedded in the phospholipid bilayer. The drug-loaded protein-phospholipid composite nanoparticle can simultaneously embed a hydrophobic drug and a hydrophilic drug, has the advantages of large drug loading capacity, high bioavailability, good stability, good transdermal permeation effect and the like, has wide application prospects in the fields of transdermal drug delivery preparations and skin care products, and is simple in preparation method, mild in reaction condition and suitable for industrial production. The method is suitable for large-scale industrial production and application.

The invention discloses multi-component inulin hydrogel as well as a preparation method and application thereof, and belongs to the technical field of nano materials and medicines.The multi-component inulin hydrogel is characterized in that a medicine L-alanyl-L-glutamine contributing to intestinal mucosa repair is entrapped in the inulin hydrogel; the multi-component inulin hydrogel has the advantages that the multi-component inulin hydrogel is prepared from the inulin and composite nanoparticles (namely mesoporous polydopamine-gallium composite nanoparticles) composed of an active oxygen scavenger polydopamine and an antibacterial agent gallium ions, the repairing capacity on intestinal barriers is further enhanced, and the prepared multi-component inulin hydrogel can be used for effectively treating inflammatory bowel diseases and non-alcoholic steatohepatitis.

The invention provides an inorganic fiber prepared from industrial solid waste and a preparation method thereof, and belongs to the technical field of inorganic fiber preparation. According to the rare earth doped low-temperature co-melt, a silicon-oxygen network is destroyed and stabilized, the viscosity of solid waste melt is reduced, phase splitting is inhibited, and a uniform melt environment is created; the viscosity of the carbon-coated composite nanoparticles is reduced through in-situ carbon thermal reduction reaction in a synergistic manner, and meanwhile, a reactant gas is utilized to clarify a melt, so that internal defects are removed; the apatite surface modified core-shell nanocrystal is used as a microstructure construction core, a fine and uniform microcrystalline phase is formed in the fiber through induction, and a high-strength basis of the material is constructed; homogenization of the low-temperature co-melt is the premise of subsequent uniform dispersion of additives, core-shell nanocrystals construct a high-strength microcrystalline matrix, carbon-coated particle cores are positioned at a phase interface, the fibers are endowed with high toughness through a physical mechanism, and comprehensive mechanical properties are improved through cooperation of the core-shell nanocrystals, the carbon-coated particle cores and the core-shell nanocrystals.

The invention discloses a zero-blood-permeation Pickering emulsion entrapment system and application thereof.The zero-blood-permeation Pickering emulsion entrapment system is prepared by the steps that spirulina protein isolate and chitosan are dissolved in deionized water respectively, and a spirulina protein isolate solution and a chitosan solution are prepared; the preparation method comprises the following steps: mixing and stirring a spirulina protein isolate solution and a chitosan solution to prepare a spirulina protein isolate-chitosan composite nanoparticle dispersion liquid; and adding an oil phase containing an active matter into the spirulina isolated protein-chitosan composite nanoparticle dispersion liquid, and homogenizing to prepare the stable Pickering emulsion of the spirulina isolated protein-chitosan composite nanoparticles. The penetration enhancing system is used for skin drug delivery, can accurately deliver the drug into the epidermis or corium layer, does not cross the skin barrier to enter blood circulation, and is an optimal drug delivery system for treating diseases in the skin or modifying the skin structure.

The invention provides magnesium manganese carbonate nanoparticles wrapped by cell membrane vesicles as well as a preparation method and application of the magnesium manganese carbonate nanoparticles. The nanoparticles comprise tumor cell-derived membrane vesicles highly expressing PD1; the MgMn nano-particle compound is wrapped in the vesicles; the magnesium manganese carbonate nano-particles (CVs (at) MgMn) wrapped by the cell membrane vesicles provided by the invention integrate numerous advantages of Mg < 2 + > and Mn < 2 + > ions, not only have immune regulation and control and tumor killing effects, but also can realize radiotherapy sensitization, have immune regulation and control and microenvironment remodeling effects on any type of solid tumors, and can be used for preparing a medicine for treating tumor tumors. And the nano-particles are universal multifunctional composite nano-particles.

This invention discloses a protein-polysaccharide ternary nanoparticle loaded with cordycepin, its preparation method, and its applications. The invention employs a layer-by-layer self-assembly method to modify the surface of zein nanoparticles. Since zein has a positive surface charge, the first layer modification uses the anionic polysaccharide sodium alginate for electrostatic bonding, and the second layer modification uses the cationic polysaccharide chitosan, constructing positively charged ternary composite nanoparticles. These nanoparticles have small particle size, high encapsulation efficiency, high drug loading capacity, and a sustained-release effect, significantly reducing cytotoxicity and significantly improving the therapeutic effect on osteoarthritis. This invention develops a novel cordycepin formulation, overcoming the limitations of cordycepin's clinical use.

The invention discloses MnO2 (at) ZIF-67 composite nanoparticles with high oxidase activity as well as a preparation method and application of the MnO2 (at) ZIF-67 composite nanoparticles. The preparation method comprises the following steps: uniformly mixing a potassium permanganate aqueous solution and a cerous nitrate aqueous solution to obtain a mixed solution I; and adding nitric acid into the mixed solution I, carrying out hydrothermal reaction to obtain a substance MnO2, uniformly mixing the obtained MnO2 and a methanol solution of PVP, adding cobalt nitrate hexahydrate and 2-methylimidazole, and standing to obtain the MnO2 ZIF-67 composite nanoparticles. The nano-particles with high enzymatic activity are prepared through a simple hydrothermal synthesis method, have good oxidase mimetic activity, catalyze O2 and TMB to rapidly develop color and become dark blue, and can specifically, sensitively and rapidly detect the total antioxidant capacity of cells, so that the nano-particles have good practical application value.

The invention discloses a multiple emulsion as well as a preparation method and application thereof. The multiple emulsion is composed of an inner water phase, an oil phase and an outer water phase, the inner water phase is composed of a whitening agent and a humectant, the oil phase is composed of vegetable oil, an antioxidant and an emulsifier, and the outer water phase is composed of resveratrol-phosphorylated zein-carboxymethyl chitosan composite nanoparticles, a penetration enhancer and a humectant. The multiple emulsion provided by the invention has good stability, antioxidant activity and moisture retention, can effectively inhibit tyrosinase activity so as to achieve the effect of whitening the skin, is non-irritant to the skin, does not destroy the micro-ecological balance of the skin, is light in skin feeling, can be used in skin care products such as essence milk, face cream, facial masks and the like, and has a very good application prospect. The method is suitable for large-scale industrial production and application.

The invention discloses camel milk protein-polysaccharide composite nanoparticles and a preparation method thereof, and belongs to the technical field of preparation of natural fermentation composite particles. The preparation method comprises the following steps: (1) inoculating phytobacterium plantarum into camel milk for fermentation, centrifuging, and collecting supernatant; and (2) carrying out ultrasonic treatment on the supernatant under an ice-water bath condition, adding absolute ethyl alcohol to precipitate after the ultrasonic treatment is finished, standing, centrifuging, and dialyzing to remove impurities, so as to finally obtain the camel milk protein-polysaccharide composite nanoparticles. According to the preparation method, camel milk is taken as a fermentation substrate, fermentation is carried out by utilizing phytobacterium plantarum LR-1, and the natural polysaccharide-protein nanoparticles (PPNPs) are successfully prepared in combination with ultrasonic treatment. In the fermentation process, the metabolic activity of lactic acid bacteria promotes the combination of protein and polysaccharide, and the particle size, the stability and the oxidation resistance are improved; the ultrasonic treatment further optimizes the particle size and structure, and enhances the oil-water interface adsorption capacity.

The invention relates to the technical field of flame-retardant materials, and particularly discloses a cellulose-based flame-retardant heat-insulating aerogel material and a preparation method thereof. By introducing metal organic frameworks (MOFs) composite nanoparticles and methyltrimethoxysilane, the skeleton structure of the cellulose aerogel is effectively reinforced, and the flame retardant property and mechanical strength of the material are remarkably improved on the premise of not sacrificing the original characteristics of the cellulose aerogel; and accurate regulation and control of the aerogel microstructure are further realized by adopting a directional freezing technology. The aerogel material has a highly-ordered vertically-arranged pore channel structure, and convective heat transfer of gas is reduced, so that the efficiency of heat conduction through gas convection is reduced. Experimental results show that the aerogel prepared by the method not only retains the advantages of light weight and low density of traditional aerogel, but also is improved in flame retardant effect and mechanical property.

This invention provides a dry powder drag-reducing agent for fracturing fluids and its preparation method, belonging to the technical field of fracturing materials for drilling. The method includes the following steps: dissolving 4-bromobutyryl chloride and N-dodecylmethylamine in acetonitrile, heating and stirring to react; adding polyethylene glycol monomethyl ether acrylate and dichloromethane; stirring under a nitrogen atmosphere; purifying to obtain a double-tailed hydrophobic monomer; mixing core-shell Fe3O4 / SiO2 composite nanoparticles, ethanol aqueous solution, KH570, and ammonia solution; stirring; purifying to obtain modified SiO2 / Fe3O4; adding acrylamide, acrylic acid, sodium 2-acrylamido-2-methylpropanesulfonate, the double-tailed hydrophobic monomer, and modified SiO2 / Fe3O4 to water; adjusting the pH value; mixing and stirring with nitrogen gas; adding an azo initiator; stirring; cooling; purifying; vacuum drying; and pulverizing into powder to obtain the dry powder drag-reducing agent for fracturing fluids. This invention achieves good drag-reducing performance while also possessing certain heat resistance, making it better suited for fracturing operations in drilling processes.

The invention provides a xanthophyll nano-particle based on electrostatic self-assembly, which is formed by electrostatic self-assembly and spontaneous aggregation of polyglutamic acid and chitosan oligosaccharide and embedding of xanthophyll at the same time. The mass ratio of the polyglutamic acid to the chitosan oligosaccharide to the xanthophyll is 4: 600: 3; the particle size of the xanthophyll nanoparticles is 180-250 nm, and the encapsulation efficiency of the xanthophyll nanoparticles is 60-90%; the preparation process comprises the following steps: mixing a polyglutamic acid aqueous solution and a xanthophyll anhydrous alcohol solution, and fully mixing and stirring for later use; dropwise adding the mixed solution into the chitosan oligosaccharide aqueous solution, and fully stirring and mixing to obtain a xanthophyll nanoparticle solution; and removing insoluble xanthophyll, and freeze-drying to obtain the xanthophyll composite nanoparticles.