3069 results about "Salt solution" patented technology

The invention relates to double-layer integrated asymmetric viscous hydrogel as well as a preparation method and application thereof, and belongs to the technical field of hydrogel. The invention relates to a preparation method of double-layer integrated asymmetric viscous hydrogel, which comprises the following steps: adding natural macromolecular polysaccharide and a polymeric monomer into a salt solution, stirring at room temperature, then adding an initiator and a cross-linking agent, stirring and polymerizing to obtain the double-layer integrated asymmetric viscous hydrogel. Through a one-pot method, a salt component is introduced into a hydrogel system, and the hydrogel has a double-layer structure with asymmetric viscosity under the salting-out action; in addition, the hydrogel is doped with a carbon nanotube with the surface modified by polydopamine and silver nanoparticles, so that the mechanical property and the conductivity of the hydrogel are remarkably improved. The preparation method provided by the invention is simple, is suitable for various hydrogel systems, has good universality and is easy to popularize and apply.

The invention belongs to the technical field of lithium batteries, and particularly relates to a lithium-rich manganese-based positive electrode material and a preparation method and application thereof. The preparation method comprises the following steps: mixing a metal salt solution, a precipitator and a complexing agent, and carrying out coprecipitation reaction on an obtained coprecipitation reaction precursor solution to obtain a lithium-rich manganese-based precursor; the metal salt solution comprises a manganese element, a cobalt element and a nickel element; and mixing the lithium-rich manganese-based precursor, a lithium source, an auxiliary agent and a dispersing agent, and calcining to obtain the lithium-rich manganese-based positive electrode material, the auxiliary agent comprises a nitrogen source or a nitrogen source and a carbon source. The first discharge specific capacity, the rate capability and the cycling stability of the lithium-rich manganese-based positive electrode material can be improved, and the problems of capacity fading, discharge voltage drop and dynamic delay in an electrochemical reaction process are solved.

The invention belongs to the technical field of chemical catalysis, and particularly relates to a preparation method of an alkali metal cation modified cobalt-nitrogen-carbon monatomic catalyst and application of the catalyst in electrosynthesis of hydrogen peroxide. The Co-N-C / X catalyst is obtained by taking a cobalt-containing compound as a metal source, mixing the metal source with a nitrogen-containing organic matter and a carbon material, performing rotary evaporation, grinding and high-temperature pyrolysis in an inert atmosphere, performing acid washing with strong acid to construct surface defects, and finally performing stirring adsorption with an alkali metal salt solution, suction filtration and drying. Alkali metal cations are physically adsorbed and anchored on the surface and interface of the Co-N-C catalyst instead of being dissolved in a solution, so that the electronic structure of Co active sites and the adsorption energy of the * OOH intermediate are optimized, and the problem of separation of alkali metal and a product is solved. When the catalyst is used for electro-catalytic oxygen reduction reaction, the H2O2 selectivity reaches up to 98%, the preparation process is simple, the cost is low, large-scale production can be realized, and the problems that the traditional method is high in energy consumption and large in pollution and the existing catalyst is insufficient in selectivity are solved.

The invention discloses a method for preparing calcium hydroxide slurry with high specific surface area and high pore volume, which comprises the following steps: S1, adding an alcohol reagent into water to obtain a solution A; s2, adding an inorganic salt solution into the solution A, and uniformly mixing to obtain a solution B; s3, a reagent X is added into the solution B, ultrasonic mixing is performed to obtain a solution C, and the reagent X is a mixture of phenol or triethanolamine, ethidene diamine and ethylamine; and S4, adding calcium oxide powder into the solution C, continuously stirring, and reacting to obtain calcium hydroxide slurry. The invention provides a method for preparing calcium hydroxide slurry with high specific surface area and high pore volume, the calcium hydroxide slurry prepared by the method can form calcium hydroxide with high specific surface area and high pore volume when in use, and the method aims to solve the problems of low specific surface area and low pore volume of the existing calcium hydroxide. Therefore, the problem of desulfurization performance inactivation caused by blockage of calcium hydroxide (desulfurizer) pores by generated CaSO3 and CaSO4 in the desulfurization process is avoided.

The invention relates to a novel composite bipolar membrane for preparing low-carbon alcohol alkali metal salt and an electrodialysis process of the novel composite bipolar membrane, and belongs to the technical field of membrane separation and electrochemical synthesis. The composite bipolar membrane comprises a cation exchange layer, a middle catalyst layer and an anion exchange layer which are sequentially laminated and compounded, the process comprises the following steps: introducing a salt solution containing alkali metal ions into an anode chamber of a bipolar membrane electrodialysis system, and introducing a low-carbon alcohol solution into a cathode chamber; applying a direct-current electric field to the two sides of the composite bipolar membrane, so that the low-carbon alcohol is dissociated at the membrane interface to generate alkoxy ions and hydrogen ions; the alkoxy ions migrate to an anode chamber to be combined with the alkali metal ions to generate low-carbon alcohol alkali metal salt; the membrane material is high in adaptability, the membrane structure is good in stability, technological parameters are mature, and the system integration degree is high.

A preparation equipment and a process for a nylon salt solution. The preparation equipment includes a suspension preparation device, a first salt formation reactor and a second salt formation reactor. The suspension preparation device includes a feeding unit, a continuous feeding unit, a high-shear pump and a mixing reactor, the high-shear pump and the mixing reactor are cyclically connected with and in communication with each other through two connecting pipelines; the second salt formation reactor includes a second diamine feed pipe, a third diamine feed pipe, a circulation pipeline of the second salt formation reactor and an online near-infrared monitoring equipment located on the circulation pipeline of the second salt formation reactor.

The invention belongs to the technical field of catalysts, and particularly relates to a high-performance palladium-carbon catalyst and a preparation method thereof. The activated carbon is subjected to high-temperature roasting, acid pickling and modification treatment, impurities on the surface of the activated carbon are effectively removed, the specific surface area and the pore structure of the carrier are enlarged, and meanwhile a large number of functional groups are introduced; the activated carbon is modified by adopting an amino compound and a sulfur-containing compound, and amino and sulfydryl are introduced to the surface of the activated carbon, so that the palladium adsorption capacity of the activated carbon is improved; a small amount of citric acid is added into the palladium salt solution, palladium ion precipitation is avoided, large-particle-size palladium particles are formed, and the dispersity of palladium is improved.

The invention provides a preparation method of grain size grading iron phosphate and high compaction type lithium iron phosphate. Removing impurities from the titanium dioxide byproduct ferrous sulfate, and filtering to obtain a purified ferrous sulfate base solution; the method comprises the following steps: reacting phosphoric acid with ammonia water to prepare ammonium phosphate solutions with different reaction pH values and phosphorus molar concentrations, respectively mixing the ammonium phosphate solutions with a certain amount of hydrogen peroxide, and sequentially adding an iron source, a first phosphorus salt solution, a second phosphorus salt solution and a third phosphorus salt solution into a tubular reactor for reaction to obtain iron phosphate slurry; and sequentially converting, filtering, washing, drying and calcining the completely reacted slurry to finally prepare the anhydrous iron phosphate. According to the invention, a mode of controlling solution nucleation and growth is adopted, nucleation and growth rates are controlled by preparing phosphorus salt solutions with different concentrations, size grading of precursor particles is directly realized in a synthesis reaction section, and slurry grading uniformity is further realized through aging crystal transformation. Lithium iron phosphate prepared from the iron phosphate precursor has high compaction density.

The invention provides a compound disinfectant for preventing and treating aquaculture virus diseases and a preparation method thereof. The composite disinfectant is prepared by introducing polyhexamethylene guanidine or a salt thereof, a quaternary ammonium salt compound, metal nanoparticles and an auxiliary agent into a water system as main raw materials, and is prepared by the following steps: adding a quaternary ammonium salt compound solution and a penetrating agent into a polyhexamethylene guanidine or salt solution thereof, and uniformly stirring and mixing to obtain a mixed solution A; slowly dropwise adding the metal nanoparticle dispersion liquid into the mixed solution A, starting ultrasonic treatment at the same time, and uniformly stirring and mixing to obtain a mixed solution B; dropwise adding the pH regulator solution into the mixed solution B, regulating the pH, adding the preservative solution, supplementing water, uniformly mixing, standing and curing to obtain the composite disinfectant. The compound disinfectant aims at achieving synergistic interaction, finally achieves the comprehensive prevention and treatment effects of being efficient, low in toxicity, broad in spectrum and not prone to inducing drug resistance, and particularly achieves efficient and safe prevention and control on fish, shrimp and crab virus diseases so as to meet the urgent requirement for healthy aquaculture.

The invention discloses a method for preparing calcium hydroxide with high specific surface area and high pore volume by a semi-dry method, which comprises the following steps: S1, adding an alcohol reagent into water, and uniformly mixing to obtain a solution A; s2, adding a composite cationic surfactant into the solution A, and dissolving to obtain a solution B; s3, adding an iron salt solution into the solution B, and uniformly mixing to obtain a solution C; s4, adding triethanolamine into the solution C, and performing ultrasonic dissolution to obtain a solution D; and S5, spraying the solution D into calcium oxide powder, continuously stirring, and reacting to prepare calcium hydroxide with high specific surface area and high pore volume. The calcium hydroxide prepared by the method has a high specific surface area and a rich pore structure, is powdery after reaction, and is relatively low in water content.

The invention belongs to the technical field of nano materials, and relates to a carbon thermal reduction driven high-entropy oxide metastable-state material and a preparation method and application thereof.The preparation method comprises the steps that S1, carbon and soluble metal salt are dissolved in a solvent for ultrasonic treatment, and a metal salt solution and a carbon suspension are obtained; s2, adding a metal salt solution into the carbon suspension, adding strong base, and stirring to obtain a coprecipitation polymer; s3, re-dispersing the coprecipitation polymer in the solvent, adding extra ferric salt and urea, mixing and stirring, and freeze-drying the mixed solution to obtain precursor powder; s4, performing staged annealing treatment on the precursor powder under low oxygen partial pressure to obtain a carbon-loaded high-entropy oxide metastable-state material; the prepared high-entropy oxide metastable-state material is of an alloy phase and high-entropy oxide double-phase coupling structure, the polarization loss of electromagnetic waves is enhanced through a heterogeneous interface, and the high-entropy oxide metastable-state material has the advantages of being excellent in impedance matching and wide in electromagnetic wave absorbing bandwidth and can be widely applied to the fields of industrial electronics, medical communication and military stealth.

The invention belongs to the technical field of catalytic materials and hydrocarbon reforming, and particularly relates to a high-entropy catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing a metal salt solution containing lanthanum, chromium, copper, zinc, manganese, nickel, iron and cobalt ions with a chelating agent and a dispersing agent for reaction, carrying out ultrasonic cavitation treatment to obtain sol, adjusting the pH value, gelatinizing under an oil bath heating condition to obtain a colloidal precursor, drying, and calcining in an air atmosphere to obtain a perovskite type high-entropy oxide precursor; and then treating in a reducing atmosphere to obtain the FeZnCuNiCo perovskite type high-entropy alloy catalyst which contains metal components of La, Cr, Ni, Mn, Fe, Zn, Cu and Co and takes a multi-metal alloy active center of Fe-Zn-Cu-Ni-Co as a main component. The high-entropy catalyst can meet the harsh requirements of high temperature, strong carbon deposition driving force and long-period operation in a propane dry reforming reaction, and is suitable for industrial application scenarios of continuous production of high-temperature synthesis gas.

The invention discloses an electric pulse and salt crystallization synergetic coal seam anti-reflection system and method, and the system comprises a salt solution preparation tank which is internally provided with a Na2SO4 saturated solution; one ends of the first high-pressure water injection pump and the second high-pressure water injection pump are respectively communicated with the salt solution preparation tank, and the other ends of the first high-pressure water injection pump and the second high-pressure water injection pump are respectively communicated with the negative electrode drill hole and the positive electrode drill hole through a first pipeline and a second pipeline; the positive electrode end of the electric pulse generating device is connected with a positive electrode, the positive electrode is arranged in the positive electrode drill hole, the negative electrode end of the electric pulse generating device is connected with a negative electrode, the negative electrode is arranged in the negative electrode drill hole, and the electric pulse generating device is configured to generate a large number of microfractures in the coal body by utilizing the electrogenerated shock wave and the Joule heating effect and drive the Na2SO4 saturated solution to diffuse towards the deep parts of the fractures; and the first cooling jet device and the second cooling jet device are respectively communicated with the negative electrode drill hole and the positive electrode drill hole and are configured to respectively inject a low-temperature medium into the negative electrode drill hole and the positive electrode drill hole.

The application provides a reverse water gas shift catalyst, a preparation method and application thereof, and the reverse water gas shift catalyst prepared by the preparation method has excellent catalytic activity and high CO selectivity in a reverse water gas shift reaction. The preparation method comprises the following steps: contacting a precipitating salt solution with a precipitant aqueous solution and performing co-precipitation, and simultaneously controlling the reaction temperature to be 40-80 DEG C and the pH to be 6-8; optionally performing aging after the co-precipitation is completed; filtering the obtained precipitate to obtain a filter cake, washing the filter cake, then drying the filter cake, and calcining the filter cake at 300-500 DEG C to obtain the reverse water gas shift catalyst; wherein the precipitating salt solution is a mixed aqueous solution of a soluble salt of divalent metal ions and a soluble salt of trivalent metal ions, the divalent metal ions are selected from divalent ions of Mg and / or Zn, and the trivalent metal ions are selected from trivalent ions of Al, In and / or Ga.

Flue gas is compressed to high pressures, which raises the partial pressure of carbon dioxide thus facilitating its absorption into physical solvents (e.g., water, salt solutions, methanol). When added onto an existing CO2-producing process, the compression is performed using multiple stages with intercooling. After the high-pressure carbon dioxide dissolves into the physical solvent, it flows through a series of pressure letdowns using turbines that allow the dissolved carbon dioxide to evolve from the solvent. Through a series of multiple compression stages, the evolved gas is compressed for transport, utilization, or storage. The flue gas that has been scrubbed of carbon dioxide flows through a series of expanders with interheating supplied from waste heat, or the heat of compression. The process is enhanced by employing alkalis that chemically react with acid gases, such as carbon dioxide. These same CO2-capture processes can be integrated into processes that produce shaft and / or electrical power.

The invention belongs to the field of chemical engineering, and relates to a preparation method of a high-chroma bismuth vanadate pigment for a coating, which comprises the following steps: mixing a titanium-based ion sieve with an acidic vanadium leachate, filtering after the reaction is completed to obtain a first filtrate, adding mercaptoacetic acid into the first filtrate, and filtering after the reaction is completed to obtain a second filtrate; preparing a bismuth salt solution containing yttrium ions and zirconium ions, mixing the bismuth salt solution with the second filtrate, adjusting the pH value to be in linear gradient change from acidity to neutrality, heating to a first temperature at a set heating rate, aging, centrifuging and drying to obtain a precursor; and calcining the precursor at a second temperature to obtain the bismuth vanadate pigment. According to the method, the acid vanadium leaching solution is used as a raw material, and the bismuth vanadate pigment with high chromaticity and chemical stability is obtained while the production cost is reduced through an innovative ion sieve purification technology and lattice stabilization doping, so that the method has obvious economic benefits.

The invention provides high-performance silver powder suitable for TOPCon battery fine grid silver paste, a preparation method of the high-performance silver powder and the silver paste, and belongs to the technical field of photovoltaic materials. The preparation method comprises the steps that a silver salt solution and a composite reducing agent are mixed, a first-stage hydrothermal reaction is carried out at the first temperature, a second-stage hydrothermal reaction is carried out at the second temperature, and silver powder is obtained after centrifugation, washing and drying; wherein the composite reducing agent is selected from a mixture of two of potassium tartrate, sodium sulfite and ferrous sulfate. According to the method, gradual growth and crystallinity improvement of silver crystal nucleuses are achieved through two-stage heating, particle aggregation or uneven morphology caused by rapid reduction is avoided, in addition, the adopted composite reducing agent combination is remarkably superior to a single reducing agent (such as ascorbic acid), and the morphology and particle size distribution of the silver powder can be more accurately regulated and controlled.

The invention discloses ternary synergistic nano-enzyme hydrogel as well as a preparation method and application thereof, and relates to the technical field of biomedical materials. The preparation method comprises the following steps: dissolving zinc nitrate hexahydrate and ferric nitrate nonahydrate in methanol; dissolving 2-methylimidazole in methanol, adding into a metal salt solution, stirring, and sequentially centrifuging, washing and drying to obtain Fe / ZIF-8 nano-enzyme; the preparation method comprises the following steps: adding methacrylated gelatin and hyaluronic acid into deionized water, stirring, cooling to room temperature, and refrigerating to obtain a GelMA-HA precursor solution; and adding the Fe / ZIF-8 nano-enzyme into the GelMA-HA precursor solution, stirring, injecting into a mold, and carrying out ultraviolet light cross-linking curing to obtain the ternary synergistic nano-enzyme hydrogel. According to the hydrogel disclosed by the invention, active oxygen is efficiently removed and oxygen is produced through Fe / ZIF-8 nano-enzyme, and cartilage repair is promoted in combination with lubrication and slow release functions of gelatin hydrogel, so that a new strategy is provided for treatment of osteoarthritis.

The application discloses a preparation method of a catalyst for liquid-phase refining of crude octanol, and the preparation method comprises the following steps: (1) mixing pretreated fly ash and pseudo-boehmite, adding deionized water and nitric acid, stirring until a colloid is formed, drying the colloid, mixing the dried colloid with kaolin, and obtaining a carrier through kneading, extrusion molding, drying and calcination; (2) taking a nickel salt, a manganese salt and a zinc salt as active components, taking a calcium salt as an auxiliary component, dissolving the active components and the auxiliary component in deionized water to obtain a salt solution, adding n-hexane into the salt solution and stirring uniformly to prepare an impregnation solution, immersing the carrier in the impregnation solution, and obtaining the catalyst through washing, drying and calcination. The catalyst prepared by the method is mainly used in a liquid-phase refining reaction process of crude octanol, and has high activity stability and selectivity.

The application provides a preparation method of an octene aldehyde liquid-phase hydrogenation catalyst, and steps of the method comprise the following: (1) preparing a salt solution containing nickel ions, copper ions and aluminum ions, heating to 40-80 DEG C, adding a basic precipitator to react, and aging after the reaction is completed; (2) uniformly mixing the precipitate obtained after aging in step (1) with silica sol to obtain slurry; (3) washing and filtering the slurry, then adding alkali metal carbonate powder and boron nitride solid, uniformly mixing, and then shaping, drying and calcining to obtain the octene aldehyde liquid-phase hydrogenation catalyst. The preparation method is simple, green, environmentally friendly and easy to industrialize, the conversion rate and selectivity of the obtained octene aldehyde liquid-phase hydrogenation catalyst are high, and the catalyst is stable in performance and durable.

The invention relates to a preparation method of a ceramic-based composite material, in particular to a preparation method of a ceramic-based composite material with a pyrolytic carbon-carbon nanotube interface, which is used for solving the problem that in the aspect of improving the thermal conductivity of an interface layer, metals such as Fe, Co, Ni and the like are widely used as catalysts for growing carbon nanotubes at present, so that the thermal conductivity of the interface layer is improved. Carbon nanotubes obtained through a traditional preparation method are prone to agglomeration and uneven in distribution, the risk of the preparation process is high, the carbon nanotubes are not suitable for large-scale production, although metal particles can be reduced through a chemical plating method, the particle sizes of the metal particles are not controlled, the distribution of the metal particles is uneven, and the requirement of a chemical vapor reduction method for distribution of an earlier-stage metal salt solution is high. And the defect is difficult to realize easily. According to the preparation method of the ceramic-based composite material with the pyrolytic carbon-carbon nanotube interface, the ceramic-based composite material with the pyrolytic carbon-carbon nanotube interface is finally obtained through pretreatment, solution A preparation, metal salt solution in-situ reduction and chemical vapor deposition in sequence.

This invention provides a method for preparing monodisperse nano-calcium carbonate from calcium-containing industrial solid waste. The method comprises the following steps: S1: mixing calcium-containing solid waste and an ammonium salt solution, reacting the mixture, and filtering to obtain a calcium-containing filtrate; S2: mixing the calcium-containing filtrate, CO2 gas, and a crystal form control agent, reacting the mixture, and filtering to obtain nano-calcium carbonate; S3: mixing the nano-calcium carbonate with an aqueous solution containing a surfactant, reacting the mixture, centrifuging, washing, and drying to obtain monodisperse nano-calcium carbonate. This method improves the calcium leaching rate from calcium-containing solid waste, achieves explosive nucleation and rapid growth of calcium carbonate, enhances the reactivity and reaction time between the surfactant and the nano-calcium carbonate particles, and improves the dispersion and surface modification degree of the calcium carbonate nanoparticles.

The invention relates to the technical field of fluorescent hydrogel, in particular to high-strength and high-stability fluorescent hydrogel as well as a preparation method and application thereof, the fluorescent hydrogel is formed by physical crosslinking of a hydrogel matrix, a rare earth fluorescent complex and a stabilizer, the hydrogel matrix is of a double-network structure formed by physical crosslinking of polyvinyl alcohol and carboxymethyl cellulose; the rare earth fluorescent complex is formed by connecting rare earth metal ions and an organic antenna material through coordination; the stabilizer is trisodium citrate. Compared with other fluorescent hydrogel, the fluorescent hydrogel with high strength and high stability provided by the invention has the advantages that the phenomena of fluorescence decay and fluorescence quenching caused by metal ions and saturated salt solution are avoided, and the fluorescence is kept stable in a wide pH range. Because the fluorescence characteristic is not influenced by environmental corrosion factors, the information can be stably displayed for a long time, and the method can be used for information encryption and anti-counterfeiting in an extreme environment.

The present disclosure provides methods for preparing a liposome composition. One of the methods includes the steps of: providing precursor liposomes encapsulating platinum-based precursors; and incubating the precursor liposomes with a salt solution to convert the platinum-based precursors to platinum-based drugs to form the liposome composition. The precursor liposomes are prepared by step of: hydrating the platinum-based drugs to form the platinum-based precursors; and adding the platinum-based precursors to a lipid bilayer vehicle to form the precursor liposomes. The liposome composition prepared by the methods shows improved encapsulation efficiency and enhanced drug loading capacity.

Provided are a wide-temperature-range solid-state electrolyte, a preparation method thereof and use thereof in solid-state lithium metal batteries. The preparation method includes: dissolving a lithium salt and a magnesium salt in a solvent to obtain a mixed salt solution; and mixing the mixed salt solution with an ammonia fluoride solution, subjecting a resulting mixture to reaction, and subjecting a resulting reaction product to centrifugation, washing, and drying in sequence to obtain magnesium-doped lithium fluoride nanoparticles; and mixing the magnesium-doped lithium fluoride nanoparticles, a liquid plasticizer, a polymer monomer and a thermal initiator to obtain a liquid precursor, and subjecting the liquid precursor to curing to obtain the wide-temperature-range solid-state electrolyte, where the polymer monomer is a mixture of ethoxylated trimethylolpropane triacrylate and hexafluorobutyl methacrylate.

The invention provides a method for preparing polyarylester by interfacial polycondensation, which comprises the following steps: dissolving a diphenol monomer in an alkali solution to prepare a bisphenol salt solution, and dissolving an interfacial catalyst in a bisphenol salt water phase to obtain a water phase; dissolving aromatic dicarboxylic acid acyl chloride in a halogenated hydrocarbon solvent to obtain an organic phase; s2, slowly adding the organic phase obtained in the step S1 into the water phase in a stirring state within 10-60 minutes, and continuously reacting for 10-120 minutes in the stirring state; the product is separated out in the form of precipitate, the precipitated precipitate absorbs the halogenated hydrocarbon solvent, so that a liquid phase main body is water, a solid phase is a muddy product containing the halogenated hydrocarbon solvent, and the obtained muddy product is filtered, washed and dried to obtain a powdery product. According to the method disclosed by the invention, the polymer is directly precipitated by controlling the solute concentration and the mixing ratio, so that the efficient in-situ removal of the solvent is realized, the solvent is directly separated from water through simple filtration, and'zero separation, zero crushing and zero distillation 'is realized.

The invention relates to the field of inorganic material preparation, and particularly discloses pseudo-boehmite and a preparation method thereof. A preparation method of pseudo-boehmite comprises the following steps: (1) mixing an aluminum salt solution and an aluminate solution, adding a crystal form regulating agent, and stirring for reaction to obtain a sol system; the crystal form regulating agent is ZnS quantum dots modified by thiohydracrylic acid; (2) adding a pore diameter guiding agent into the sol system, and aging for 6-8 hours; the pore diameter guiding agent is a compound of a polyethylene glycol-polypropylene glycol-polyethylene glycol triblock copolymer and sodium citrate; and (3) carrying out solid-liquid separation on the aged sol system, and washing and drying the obtained solid to obtain the pseudo-boehmite. The proportion of 5-10nm pores of the pseudo-boehmite prepared by the preparation method disclosed by the invention reaches 90% or above, so that the pore distribution requirement of a fine catalytic reaction on the pseudo-boehmite can be met, and the efficient catalytic reaction is favorably realized.

The invention discloses a high-strength microneedle with directional holes for biological analysis sampling and a preparation method of the high-strength microneedle, and belongs to the technical field of microneedles, the method comprises the following steps: filling a silk fibroin solution into a microneedle mold to form a microneedle preform, the microneedle preform comprising a needle body part and a backing part; performing directional freezing on the microneedle preform to enable ice crystals to directionally grow in the direction from the backing part to the needle body part, and demolding to obtain a frozen blank; the frozen blank is placed in an organic solution of a cross-linking agent, soaked at the low temperature lower than 0 DEG C for ice template low-temperature solvent exchange-cross-linking treatment, taken out and cleaned, then soaked in a salt solution for salting-out treatment strengthening, taken out and cleaned and freeze-dried, and the high-strength microneedle with the directional holes is obtained. The microneedle prepared through the method has high strength and excellent puncture performance, and the skin interstitial fluid collection speed and efficiency are greatly improved.

The invention provides a processing method and application of seaweed mud-based biochar. The method comprises the following steps: (1) cleaning and deodorizing treatment: adding water into seaweed mud, stirring, precipitating and separating impurities, adding a sodium hydroxide solution, carrying out alkali washing and swelling, removing impurities and fishy smell, and forming a porous structure; (2) adding an iron salt solution for pretreatment to enable the seaweed mud to adsorb iron ions, filtering after adsorption is completed, and performing ball milling on a filtered product to obtain ball-milled seaweed mud particles; (3) pre-oxidizing in an air atmosphere, raising the temperature to 160-180 DEG C, and keeping the temperature for 2-5 hours; and (4) performing pyrolysis under the protection of nitrogen, heating to 900-1300 DEG C, and keeping the temperature for 8-16 hours to obtain the seaweed mud-based biochar. Through the steps of cleaning, alkali washing, ferric salt adsorption, pre-oxidation, pyrolysis and the like, impurities are effectively removed, the structure of the seaweed mud is improved, the mechanical property and conductivity of the seaweed mud are improved, and the seaweed mud can serve as an adsorption material or a fiber additive.

The invention belongs to the field of flame retardance of high polymer materials, and relates to a preparation method of a metal organic framework polyphosphazene flame retardant and application of the flame retardant in PET flame retardant modification.The preparation method comprises the steps that a metal salt solution and a phytic acid solution are mixed according to the molar ratio of (3-15): 1, the pH is adjusted to 7-8, alcohol is added for a reaction, and phytic acid-based MOFs are obtained; mixing the phytic acid-based MOFs with a 4, 4 '-disubstituted diphenyl compound, triethylamine and alcohol to obtain a second mixed solution; hexachlorocyclotriphosphazene (HCCP) is mixed with the second mixed solution, the molar ratio of the 4, 4 '-disubstituted diphenyl compound to the HCCP is (2-4): 1, the mixture reacts at the temperature of 20-90 DEG C, and the phytic acid group MOFs (at) HCCP is obtained. HCCP is hybridized on the surface of phytic acid-based MOFs, and the flame retardant has excellent flame retardance and environmental protection performance by utilizing the char-forming catalytic capability of the phytic acid-based MOFs and the phosphorus-nitrogen flame retardance characteristic of HCCP.