413 results about "Electrostatic attraction" patented technology

The invention discloses a high-temperature-resistant astaxanthin microcapsule and a preparation method and application thereof, and relates to the field of nutritional products, the microcapsule comprises: a, a core material: astaxanthin oil selected from haematococcus pluvialis or krill oil; b, double-layer wall materials: an inner-layer wall material is formed by crosslinking sodium alginate and whey protein through an ionic gel method; the outer-layer wall material is formed by electrostatic adsorption of chitosan and Arabic gum; and c, an antioxidant synergist: a rosemary extract. A double-layer embedding structure is adopted outside astaxanthin oil, sodium alginate on the inner layer is combined with whey protein to form a compact network structure through ionic bonds, chitosan on the outer layer and Arabic gum form a compact composite film on the surface of a primary embedded microsphere through electrostatic attraction, so that the double-layer embedded microcapsule has the advantages that the astaxanthin oil has good stability, and the astaxanthin oil has good stability. The temperature resistance limit of a traditional single-layer microcapsule is broken through, the stability of the astaxanthin in a high-temperature baking environment is remarkably improved, the astaxanthin can stably exist in high-temperature baked food, and the anti-oxidation effect and the like of the astaxanthin are fully exerted.

The invention belongs to the technical field of biological medicines, and particularly relates to hydrogel with photo-thermal multiple antibacterial and hemostatic functions. The multifunctional hydrogel is prepared from epsilon-polylysine (EPL), gallic acid (GA), tannic acid (TA) and ferric trichloride hexahydrate. The polyphenols are obtained through multiple mechanisms such as reaction between the polyphenols and amino groups, metal chelation, pi-pi interaction and electrostatic attraction (as shown in Figure 1). The metal ion and multiple dynamic cross-linking system hydrogel is constructed, the hydrogel with positive charges enriched on the surface can act with blood platelets with negative charges, red blood cell aggregation, blood platelet adhesion and vasoconstriction effects are promoted, and the blood coagulation efficiency is improved. The hydrogel shows excellent antibacterial performance and photo-thermal performance, can prevent infection in the inflammation stage of wound healing, can effectively accelerate wound healing, and has good biological safety.

The invention discloses a self-response odor-removing and sterilizing material, a preparation method thereof and a refrigerator, and belongs to the technical field of refrigerator adsorption materials. Comprising main materials and auxiliary materials, the main body material is composed of an adsorption material and a formaldehyde removal agent; the auxiliary material is composed of a response material and a bactericide; the response material is selected from a covalent organic framework; the bactericide is selected from benzimidazole compounds; the benzimidazole compound shows a deprotonation trend when the pH value is any one value of 2.8-7.1, and is combined with the covalent organic framework through electrostatic attraction; when the pH value is less than 2.8, the benzimidazole compound and the covalent organic framework are protonated at the same time, and the benzimidazole compound is released. The sterilization material is applied to the refrigerator sterilization aspect, and the problems that the sterilization effect is not lasting due to the fact that a common odor-removing sterilization material plays a role to release sterilization substances from the beginning of application, or the sterilization material cannot be actively released, the sterilization effect can be achieved only when bacteria are adsorbed on the surface of the sterilization material, and the bacteria in the air cannot be killed are solved.

The invention discloses a high-adhesion super-hydrophobic protective coating process method and a coating. The high-adhesion super-hydrophobic protective coating process method comprises the following steps: S1, preparing magnetic nano iron oxide particles; s2, performing neodymium modification on the magnetic nano iron oxide particles to obtain ferromagnetic neodymium modified iron oxide; s3, preparing and spraying a neodymium modified iron oxide coating; s4, preparing and coating a negative charge modified polymer microsphere coating; s5, preparing and spraying a positive charge modified polymer microsphere coating; and S6, preparing and spraying a modified nano silicon dioxide super-hydrophobic coating. According to the method, neodymium-modified magnetic nanometer iron oxide serves as a first layer of the surface of a steel substrate and is sprayed and dried in a magnetic field, it is guaranteed that the neodymium-modified magnetic nanometer iron oxide is tightly adsorbed to the steel surface, a magnetic transition layer is formed, and then coatings with different charges are alternately coated through the electrostatic attraction effect; and finally, a high-adhesive-force super-hydrophobic coating is formed on the steel surface in a layer-by-layer self-assembly mode, and the problem that the adhesive force of the super-hydrophobic coating is poor is obviously solved.

The invention provides novel liquid-liquid phase separation microparticles (LLPS MPs) as well as a preparation method and application thereof. The liquid-liquid separation (LLPS) system is micron liquid drops formed by driving under the electrostatic attraction effect of positively charged polyelectrolyte and negatively charged inorganic salt or organic salt in an aqueous solution. Polyoxometallate (POM) is used to stabilize it by electrostatic attraction and precipitate LLPS MPs having a ridge structure. According to the preparation method, [{(B-alpha-PW9O34) Co3 (OH) (H2O) 2 (O3PC (O) (C3H6NH3) PO3)} 2Co] 14-(Co7-POM) with photocatalytic water oxidation activity is selected to deposit micron particles, so that the micron particles have enhanced photocatalytic water oxidation activity, and meanwhile, the micron particles can be recycled through simple and feasible solid-liquid separation.

The invention relates to the technical field of ceramic fillers, in particular to a preparation method of a high-performance ceramic filler, which comprises the following steps: raw material preparation: selecting zirconium oxide powder as a raw material, dividing the raw material into a component A and a component B, the particle size of the zirconium oxide powder of the component A is 4 [mu] m, the particle size of the zirconium oxide powder of the component B is 20 [mu] m, the mass ratio of the component A to the component B is 2: 8, and the mass ratio of the component A to the component B is 2: 8; and corrosion treatment: carrying out corrosion treatment and electrostatic treatment on the component B zirconium oxide powder, and carrying out electrostatic treatment on the component A zirconium oxide powder. In the invention, the zirconium oxide powder of the component A and the component B has opposite charges, and the superfine powder can be uniformly adsorbed on the surface of the fine powder by utilizing electrostatic attraction, that is, the zirconium oxide powder of the two components can be mutually combined to form a zirconium oxide powder raw material with very rich surface pores, so that the specific surface area and the porosity performance of the ceramic filler are improved.

The invention relates to a nickel-free hole sealing agent and a preparation method thereof, and belongs to the technical field of high polymer materials. The nickel-free hole sealing agent comprises the following components in parts by weight: 3-10 parts of cobalt acetate, 1-11 parts of a corrosion-resistant modifier, 1-6 parts of ethylenediamine tetraacetic acid, 3-7 parts of sodium silicate and 5-15 parts of deionized water, an intermediate product containing bis-imidazoline in the corrosion-resistant modifier is tightly adsorbed on the metal surface by virtue of electrostatic attraction and a large pi bond to form a tough protective film, so that a water-phase corrosive medium is effectively isolated, the corrosion speed is remarkably reduced, and meanwhile, the corrosion-resistant modifier has good heat-resistant stability and still has a corrosion inhibition effect in a high-temperature environment; the glycine enables the nickel-free hole sealing agent to better fill tiny holes in the metal surface, so that the surface is flat and smooth, and uniform distribution and permeation of the hole sealing agent are promoted; quaternary ammonium salt destroys cell walls and cell membranes of microorganisms and inhibits growth and reproduction of the microorganisms; the nickel-free hole sealing agent prepared by the invention not only has a good antistatic effect, but also has excellent high-temperature-resistant and antibacterial effects.

The invention belongs to the technical field of water treatment, and particularly relates to an iron-carbon composite material, a preparation method of the iron-carbon composite material and application of the iron-carbon composite material to synchronous removal of perfluoro and polyfluoroalkyl compounds. According to the iron-carbon composite material provided by the invention, the iron metal element is anchored on the carbon carrier material in a nanocluster form, so that the problem of new pollution caused by iron dissolution is avoided, and the iron-carbon composite material is high in adsorption rate, large in adsorption capacity, recyclable and good in long-term stability. According to the invention, the PFAS is captured through hydrophobic interaction and electrostatic attraction by utilizing the coding characteristics, excellent adsorption performance is shown in treatment of various pollutants, rapid, efficient and synchronous removal of the PFAS is realized, and meanwhile, the high utilization rate of the iron-carbon composite material is ensured. As an adsorbent, the iron-carbon composite material provided by the invention is particularly suitable for repairing a perfluorooctanoic acid and / or perfluorooctane sulfonic acid combined polluted water body, the repairing is efficient, the cost is low, the removal condition of pollutants can be accurately judged, and the iron-carbon composite material is suitable for underground water or surface water.

The invention relates to a super-flexible supercapacitor with a multi-layer seamless interlocking interface and a preparation method of the super-flexible supercapacitor. The super-flexible supercapacitor takes a carbon nanotube or a composite film thereof as an electrode; and polyanion gel (polyacrylamide / polyacrylic acid / poly (3-sulfonic acid propyl methyl acrylic acid potassium salt) and polycation gel (polyacrylamide / polyacrylic acid / poly (methacryloyloxyethyl trimethyl ammonium chloride) are used as the double-layer heterogeneous electrolyte. A covalent connection electrode / electrolyte interface is constructed through anchoring interface polymerization, and double-layer gel electrolyte with electrostatic attraction and mutual entanglement is constructed through in-situ polymerization, so that the super-flexible supercapacitor with a multi-layer seamless interlocking interface is realized. Compared with the prior art, the super capacitor has super-strong interface toughness and interface adhesion, can resist mechanical deformation including bending, folding, twisting, winding, extruding, knotting and the like, the capacity retention ratio is greater than 95% after the super capacitor is folded for hundreds of thousands of times, and the capacity retention ratio is greater than 89% after the super capacitor is circularly charged and discharged for hundreds of thousands of times.

The invention discloses a controllable degradation antibacterial filament fiber and a preparation method thereof, a calcium alginate filament fiber is prepared by using a wet spinning technology, and the calcium alginate filament fiber is strongly modified by physical and chemical methods respectively. The chemical modification adopts a cross-linking agent for modification, and the physical modification adopts cellulose nanocrystal (CNC) as a reinforcing material. The tensile breaking strength is improved to 43.25 cN / dtex from 16.35 cN / dtex which is not modified, the tensile breaking strength is improved by 2.6 times, and the degradation period is prolonged to 7 days from 2 days. On the basis, berberine is introduced into the fiber, so that the mechanical enhancement effect can be further achieved by means of the electrostatic attraction effect between materials, the antibacterial performance is obtained, and the antibacterial rate can reach 95.28%.

Disclosed herein is a composition for enhanced ultrasound ablation and methods relating to same. The composition may include a microbubble-microdroplet cluster composition, wherein the microbubble-microdroplet cluster composition may include groups of negatively charged microbubbles and positively charged microdroplets permanently held together by their opposing electrostatic attractive forces to form a single, agglomerated entity.

The invention belongs to the technical field of oil field drilling, and particularly relates to a preparation method of modified sulfonated phenolic resin for drilling fluid, and the modified sulfonated phenolic resin is prepared by chemically bonding a functional monomer simultaneously containing sulfonic acid anions and quaternary ammonium cations in a phenolic resin structure in a free radical polymerization mode. The quaternary ammonium cation group adsorbs negatively-charged clay particles, the adamantyl group can be adsorbed in hydrophobic areas of the clay particles through association, and the sulfonated phenolic resin can be quickly adsorbed on the surface of the clay in a double adsorption mode of hydrogen bonds and electrostatic attraction. Besides, a large number of sulfonic acid anions can form a compact solvation layer after hydration, and a compact coating film can be formed when phenolic resin is quickly adsorbed on the surface of clay, so that the clay is prevented from being in contact with water, the stability of clay particles is realized, a compact mud cake can be formed, and the prepared phenolic resin has good filtrate loss reduction performance.

The invention relates to a eutectic-coated composite solid electrolyte as well as a preparation method and application thereof. The composite solid electrolyte comprises a fluorinated solid electrolyte and an eutectic coating layer coating the surface of the fluorinated solid electrolyte, the preparation method comprises the following steps: immersing a solid electrolyte material into a prepared fluorination treatment solution, and enabling dissociated F <-> in the fluorination treatment solution to be subjected to substitution reaction on unsaturated coordinated metal sites on the surface of the solid electrolyte material to form bonding of F <-> and metal elements, so as to obtain a fluorinated solid electrolyte; the preparation method comprises the following steps: mixing and ball-milling a fluorinated solid electrolyte and an eutectic liquid containing a cyano-Li < + > coordination cluster, and inducing to form an eutectic coating layer under the electrostatic attraction action between Li < + > in the cyano-Li < + > coordination cluster in the eutectic liquid and F <-> exposed on the surface of the fluorinated solid electrolyte, so as to obtain the eutectic-coated composite solid electrolyte, when the composite solid electrolyte is applied to the lithium battery, the electrochemical performance of the lithium battery can be improved.

A preparation method for a micro-vehicle formed by enveloping siRNA-loaded polypeptide dendrimer nanogel with a cell membrane of engineered MSCs, and the use of same. The method comprises: using lentivirus-mediated gene transfection technology for constructing MSCs that highly express CXCR4 and PSGL-1; using cytokinin B for stimulating a cell to generate vesicles, and then performing centrifugation to collect the vesicles; by means of the electrostatic attraction between polypeptide dendrimer nanoparticles and siRNAs, attaching the siRNAs of IL-6 and HIF-1α into the polypeptide dendrimer nanoparticles; and by means of using a membrane extruder, enveloping the siRNA-loaded polypeptide dendrimer nanogel with the cell membrane. The prepared micro-vehicle exhibits a good property of aggregating at inflammatory blood vessel sites and a targeting function for joint cavities with rheumatoid arthritis. In addition, the loaded siRNAs can inhibit the expressions of IL-6 and HIF-1α in the joint cavities and inhibit the cell migration and angiogenesis. The micro-vehicle targeting inflammation sites has the advantages of excellent biocompatibility, ideal siRNA loading ratio, good inflammation targeting function, etc.

The invention relates to the technical field of ore flotation, and discloses a preparation process of a foaming agent. The foaming agent is obtained by mixing fluorine-containing pyridine modified carboxyl betaine, sulfonic group modified polyoxyethylene ether and methyl isobutyl carbinol. Fluorine atoms can enhance the stability of the foaming agent and improve the flotation effect; sulfur atoms and metal ions form a stable chelate, and mineral separation and purification are achieved; pyridyl can generate electrostatic attraction with the surface of the mineral to form a hydrophobic membrane, so that the adhesive force of bubbles and the mineral is improved, and the flotation effect is enhanced; polar groups in the carboxyl betaine are adsorbed on the surfaces of the minerals, and non-polar groups face outwards, so that the surfaces of the minerals are hydrophobic, and a flotation effect is achieved; sulfonic groups can be adsorbed on the surfaces of minerals, so that the original hydrophilic surfaces of the minerals are changed into hydrophobic surfaces, and the floatability of the minerals is improved; the polyoxyethylene ether has good dispersing performance, so that the foaming agent is more uniformly distributed in ore pulp, and minerals can be better captured by bubbles and float upwards.

The utility model discloses a wear-resistant reflective zipper, which relates to the technical field of reflective zippers, and comprises a base cloth, the base cloth comprises a lining body cloth and a reflective part, the lining body cloth and the reflective part are interlaced and woven with each other, the reflective part consists of a plurality of reflective fibers, and the reflective fibers further comprise matrix fibers and bonding layers coated on the outer surfaces of the matrix fibers. The reflective effect is achieved through the high refractive index of the polymer type reflective glass beads, and the tin film layer arranged at the bottom of the polymer type reflective glass beads can further reflect external light and diffused light generated by the polymer type reflective glass beads, so that the reflective effect of the zipper is further improved; the polymer type reflective glass beads are tightly combined with the reflective layer through strong electrostatic attraction force, the reinforcing layer and the wear-resistant layer which are arranged in a matched mode have a good wear-resistant effect, the service life of the reflective zipper can be further prolonged, the falling speed of the polymer type reflective glass beads is greatly delayed, and the service life of the zipper is prolonged. And the reflective zipper can have a good reflective effect for a long time.

A workpiece attraction device is provided that can dechuck (separate) the attracted workpiece in a short time and reliably even when transporting thin workpieces such as paper, cloth, or resin films. A workpiece attraction device includes: an electrostatic attraction body (1) capable of attracting a workpiece (W) to a workpiece attraction surface (1a) by applying a voltage to an attraction electrode (4a, 4b); and a workpiece separation body (5) that is interposed between an attracted workpiece and the electrostatic attraction body, and assists in separating the workpiece from the workpiece attraction surface after application of voltage to the attraction electrode is stopped. In the workpiece attraction device, the workpiece separation body has a plurality of opening portions (6) for applying a workpiece attraction force, generated on the workpiece attraction surface, toward a workpiece, the workpiece separation body is partitioned into the opening portions by a lattice portion (7) so that the opening portions are substantially uniformly present within a plane of the workpiece separation body, and in a plan view from a workpiece side with a workpiece attracted, the attraction electrode of the electrostatic attraction body does not face the lattice portion of the workpiece separation body.

The invention belongs to the technical field of composite materials, and particularly relates to aldehyde aromatic compound crosslinked polyethyleneimine as well as a preparation method and application thereof. Amino groups in polyethyleneimine are combined with different substances, so that the adsorption capacity of the aldehyde aromatic compound crosslinked polyethyleneimine is improved; the polyethyleneimine has high cationic property in water and can neutralize and adsorb anions or chelate noble metal ions, so that the adsorbability of noble metal is improved; amino in a polyethyleneimine structure can be subjected to a cross-linking reaction with an aldehyde aromatic compound, and C = N double bonds are introduced into polyethyleneimine, so that the adsorption performance on noble metal ions is improved. The aldehyde aromatic compound cross-linked polyethyleneimine provided by the invention has a mesoporous structure, gold ions and platinum ions are adsorbed to the surface of a material and the inside of pore channels through various mechanisms such as electrostatic attraction, chelating coordination and oxidation reduction, and the adsorption capacity to metal ions, especially the gold ions and the platinum ions, is improved.

The invention relates to the technical field of protective films, and discloses a mobile phone protective film and a preparation method thereof. Modified graphene oxide is used as a filler, a modified waterborne polyurethane emulsion is used as a film forming substance, a flatting agent and a defoaming agent are used as auxiliary materials, a waterborne polyurethane coating is prepared, the surface of a PET base material is coated with the waterborne polyurethane coating, then drying is conducted, and the mobile phone protection film is obtained. A quaternary ammonium salt group and negative charges on a bacterial cell membrane generate electrostatic attraction, so that the original structure and function of the cell membrane are destroyed, and a bactericidal effect is achieved; silanol groups generated by hydrolysis of silane groups can react with hydroxyl groups and carboxyl groups on the surface of a PET base material, so that the interface bonding force between the coating and the base material is improved; nitrogen atoms in pyrrolidone groups form hydrogen bonds with hydroxyl groups and carboxyl groups on the surface of a base material, so that the bonding strength of the coating and the base material is further improved; the adamantyl group is grafted into the graphene oxide, so that the supporting effect of the graphene oxide on the waterborne polyurethane is enhanced, and the mechanical property of the mobile phone protective film is improved.

The invention relates to a high-performance positively charged composite membrane and a preparation method thereof, in particular to a nanofiltration membrane containing a sulfonated imino covalent organic framework (TpPa-SO3H) interlayer. The nanofiltration membrane adopts a three-layer structure design, and comprises a base membrane layer, a TpPa-SO3H middle interlayer and a positively charged separation surface layer. Wherein the TpPa-SO3H interlayer is formed by in-situ growth of polyphenol and sulfated amine under the action of an oxidizing agent, and the separation surface layer is assembled and constructed through electrostatic attraction and hydrogen-bond interaction between positively charged polyelectrolyte and sulfonic acid groups. The TpPa-SO3H interlayer is introduced to effectively regulate and control the pore size distribution and hydrophilicity of the surface of the substrate, the formed negative electricity interlayer can promote the assembly of a polyelectrolyte positive electricity layer, and the interception performance and the operation stability of the composite membrane on heavy metal cations are remarkably improved. Compared with a traditional nanofiltration membrane, the composite membrane prepared through the method keeps high water flux (larger than or equal to 40 L.m <-2 >. H <-1 >. Bar <-1 >), meanwhile, the rejection rate of heavy metal cations such as Cr < 3 + >, Mn < 2 + > and Co < 2 + > is larger than or equal to 95%, and the composite membrane has excellent long-term operation stability. The preparation method is simple in process and low in cost, and has a wide application prospect in the field of heavy metal wastewater treatment.

The invention discloses a method for efficiently removing perchlorate in wastewater based on quaternary ammonium salt assisted ultrafiltration, which comprises the following steps: adding quaternary ammonium salt with the carbon chain length of C12-C16 into perchlorate wastewater, enabling quaternary ammonium cations and perchlorate to form nanoscale floc through hydrophobic interaction, electrostatic attraction and Van der Waals force, and filtering through an ultrafiltration membrane to obtain the perchlorate. The high-selectivity and high-efficiency removal of the perchlorate in the wastewater is realized. The method is simple and convenient to operate, can be completed only by adding trace quaternary ammonium salt and combining the trace quaternary ammonium salt with a conventional ultrafiltration process, does not need complex equipment or a regeneration process, avoids the problem of secondary pollution caused by an adsorption material, and is remarkably improved in environmental friendliness. Meanwhile, the composite material also has good anti-anion interference capability and low flux attenuation. The method is wide in material source, low in cost, easy and convenient to operate, free of regeneration, low in operation cost and free of secondary waste, has good engineering popularization potential and is particularly suitable for on-site rapid treatment and large-scale application of perchlorate wastewater.

A plasma processing method for processing a wafer located inside a plasma processing apparatus having a lift pin disposed inside a wafer stage, the plasma processing method including setting an electrical resistance value between a direct current power source and the lower portion of the lift pin electrically connected to the direct current power source based on an electrical resistance set value between the electrostatic attraction electrode and the wafer, an electrical resistance set value between the plasma and a ground electrode of the processing chamber, and a withstand voltage set value between the plasma and the processing chamber, and adjusting a voltage value of the lower portion of the lift pin and an average value of the voltage of the electrostatic attraction electrode during the processing of the wafer to match a predicted value of a self-bias voltage of the wafer.

The invention provides a preparation method of dendritic mesoporous silicon bionic nanoparticles loaded with RNA (Ribonucleic Acid) molecules, which comprises the following steps: preparing dendritic mesoporous silicon nanoparticles DMSNs by adopting a double-phase layering method, dissolving a surfactant CTAC and a catalyst TEA in water to serve as a water phase solution, dissolving ethyl silicate TEOS in cyclohexane to serve as an oil phase, slowly dropwise adding the oil phase into the water phase, and reacting for 2-4 hours to obtain the dendritic mesoporous silicon bionic nanoparticles loaded with the RNA molecules. The DMSNs nanoparticles are obtained; amino groups are introduced to the surfaces of DMSNs through gamma-aminopropyltriethoxysilane APTES so as to enhance electrostatic attraction to nucleic acid, and after a surfactant template is removed, the DMSNs are mixed with RNA molecules in ribozyme-free water; meanwhile, a cytoplasmic membrane is harvested by using a hypotonic method, and the dendritic mesoporous silicon bionic nanoparticles loaded with the RNA molecules are prepared through ultrasonic treatment and polycarbonate film extrusion. The method is simple and convenient, and has a wide application prospect in RNA delivery.

The invention belongs to the technical field of biochar immobilized microorganisms, and particularly relates to a preparation method of a biochar-based composite material for efficient immobilization of adaptive microorganisms. The microbial loading capacity is remarkably improved, the chain structure of the attapulgite layer provides a large number of linear adsorption sites, the porous structure of the biochar forms a three-dimensional adsorption space, and the chain structure and the porous structure of the biochar construct a synergistic adsorption mode; when the ammonium ferric citrate is modified, a decomposition product of the ammonium ferric citrate can form new mesopores / micropores in the carrier to enlarge the specific surface area, and the Fe element can be coordinated with an Si-O bond of the attapulgite and a carbon skeleton of the charcoal, so that pore collapse is inhibited, and the cycle stability is improved. And hydroxyl groups on the surface of the attapulgite and oxygen-containing functional groups of the charcoal cooperate with each other, so that electrostatic attraction and hydrogen bond binding force to the microorganisms are enhanced. The microorganism survival microenvironment is optimized, the composite carrier has the ion exchange capacity of the attapulgite and the water and fertilizer retention characteristic of the biochar, and a stable buffer environment and nutrition reserve can be provided for microorganisms.

The invention discloses toothpaste which is pasty and comprises an abrasive, a humectant, a foaming agent, water, a bacteriostatic agent povidone iodine, 0.5 wt%-5 wt% of magnesium carbonate particles and 5 wt%-15 wt% of chitosan.The toothpaste has the advantages that cross-linking points are formed through electrostatic attraction between a positively charged chitosan acid solution and negatively charged povidone iodine and silicon dioxide particles; the preparation method comprises the following steps: preparing chitosan by virtue of a sol-gel method so as to realize gelation of the chitosan, uniformly dispersing silicon dioxide particles, povidone iodine and magnesium carbonate nanoparticles in the chitosan gel to obtain pasty toothpaste with good performance, the pasty toothpaste has relatively good stability, and the gel structure can also be used as a carrier to load and slowly release povidone iodine, so that the antibacterial action time of the povidone iodine is prolonged, and long-acting antibacterial protection is provided. The toothpaste disclosed by the invention has a good cleaning effect and antibacterial performance, is suitable for more user groups, especially crowds with sensitive oral cavities, and has important market requirements and application prospects.

The invention belongs to the technical field of biomedical materials, and particularly relates to a mesoporous silica functional filler and a preparation method thereof, and a composite resin material and a preparation method and application thereof. The mesoporous silica functional filler provided by the invention has remineralization performance and pH response type. Functional modification is carried out on the surface of mesoporous silica, the modified mesoporous silica can load phosphorylated chitosan / amorphous calcium phosphate through electrostatic attraction, and the pH response performance is given to the modified mesoporous silica. The phosphorylated chitosan can simulate the effect of dentin matrix protein 1, can regulate the remineralization process of dentin, and can chelate calcium ions to stabilize amorphous calcium phosphate in the solution to form an amorphous nano precursor. The polyelectrolyte may be replaced with a biomimetic analog to initiate the remineralization process. The size of the mineral precursor and the deposition sequence and layer of the mineral precursor inside and outside the collagenous fiber can be regulated and controlled, and meanwhile nucleation and growth of apatite crystals inside and outside the collagenous fiber can be promoted.

The invention discloses a preparation method of novel stimuli-responsive foam, and belongs to the field of colloid and interface chemistry. The novel foam is jointly stabilized by an ionic surfactant and nanoparticles with the same charge. The stimulation-responsiveness of the foam takes an anion-cation pair as a trigger mechanism. The microstructure of the foam is different from that of common foam and Pickering foam, a low-concentration surfactant is adsorbed on a water / air interface and endows bubbles with surface charges, and nanoparticles are distributed in a water phase to form a thick water film, so that the distance between the bubbles is increased, Van der Waals gravitation between the bubbles is greatly reduced, and therefore, the foam can be used for preparing the water-based foam. And through repulsive interaction of double electric layers between particles, bubbles and bubbles and between particles and bubbles, coalescence of the bubbles is prevented, and stable bubbles are formed. When the anionic surfactant with the same mole as the cationic surfactant is added into the stable foam, the anionic surfactant and the cationic surfactant form ion pairs through electrostatic attraction, so that the cationic surfactant is desorbed from a water / air interface, and the foam disappears.

The invention belongs to the field of fuel cell catalysts, and particularly discloses a PtCo intermetallic compound and a preparation method and application thereof. The preparation method comprises the following steps: slowly dropwise adding a potassium chloroplatinite solution into a solution dispersed with [Co (NH3) 5Cl] Cl2 and carbon powder, carrying out electrostatic attraction to form a bimetallic complex salt crystal, and carrying out high-temperature heat treatment to obtain the PtCo intermetallic compound which can be used as a catalyst in the field of fuel cells ORR. Starting from the source of synthesizing the intermetallic compound, the precisely constructed Pt-Co bimetallic complex salt crystal is loaded on the carbon carrier, and small-size and high-activity Pt1Co1 intermetallic compound nanoparticles can be directly obtained through high-temperature heat treatment; according to the present invention, the ORR catalytic activity is superior to the commercialized Pt / C, the durability is outstanding, and the performance is extremely high in the fuel cell test, such that the advanced synthesis strategy is provided for the preparation of the new generation of the fuel cell ORR catalyst in the future.

The invention discloses a preparation method of a layer-by-layer casting ultrathin asymmetric bipolar membrane, and belongs to the technical field of membrane separation. The invention aims to solve the problems that the total thickness of the traditional bipolar membrane is small, the water decomposition rate is low, and the conversion efficiency of different salts is obviously different. The asymmetric bipolar membrane is prepared by using a layer-by-layer casting method, and the thickness of the anion exchange layer and the cation exchange layer of the membrane is regulated, so that ion leakage is avoided, and the product purity is remarkably improved; the anion-cation exchange layer is prepared from a polymer with charge, and the adhesion capacity of the membrane is greatly improved by virtue of electrostatic attraction through the characteristic of opposite charge of the anion-cation exchange layer, so that the membrane is prevented from swelling in water. According to the invention, the anion and cation exchange membranes are adhered together through electrostatic adsorption force by virtue of the characteristic of opposite charges, the adhesion strength of the membrane is enhanced by virtue of the chemical compatibility of SPPSU and QPPO, the membrane has good mechanical property, and the service time and frequency of the membrane are improved.

The invention discloses a gradient composite light regeneration water treatment flocculant as well as a preparation method and application thereof. The preparation method comprises the following steps: 1, mixing nano chitin fibers, a lignin-polyphenol complex and photocatalytic microspheres obtained by loading Fe3O4 (at) TiO2 nanoparticles on sodium alginate; 2, cross-linking to form a homogeneous colloid; 3, directionally arranging in a magnetic field; and 4, gradient freeze drying. According to the invention, the nano chitin fibers, the lignin-polyphenol complex and the photocatalytic microspheres are crosslinked to form the gradient composite light regeneration water treatment flocculant, and the flocculant has a four-dimensional adsorption mechanism of electrostatic attraction, pi-pi accumulation, coordination complexation and spatial screening; the efficient removal capability on various pollutants such as heavy metal ions, organic pollutants and suspended solids can be realized. In addition, due to the high crystallinity of the nano chitin fibers, a mechanical supporting effect can be achieved on the interior of the flocculating agent, and the magnetic agglomeration phenomenon of magnetic nuclei containing Fe3O4 is prevented.