12 results about "N dimethylformamide" patented technology

The invention discloses lithium-free high-heat-resistance ceramic pug and a preparation method thereof, and relates to the technical field of ceramic materials. When the lithium-free high-heat-resistance ceramic pug is prepared, aluminum oxide reacts with 3-(2, 3-epoxypropoxy) propyltrimethoxysilane to prepare pre-modified aluminum oxide; reacting the pre-modified aluminum oxide with starch to obtain modified aluminum oxide; mixing ethyl acetoacetate, isopropanol, zirconium oxychloride, aluminum sec-butoxide, polyvinylpyrrolidone and N-N dimethylformamide to prepare a spinning solution, performing electrostatic spinning, and then immersing the spinning solution into the yttrium oxide sol to prepare aluminum oxide-zirconium oxide-yttrium oxide composite fibers; stirring and mixing the modified aluminum oxide, talc, aluminum oxide-zirconium oxide-yttrium oxide fibers, hydroxypropyl methyl cellulose, glycerol, oleic acid, polyethylene glycol and water, and performing vacuum pugging to obtain the lithium-free high-heat-resistance ceramic pug. The lithium-free high-heat-resistance ceramic pug prepared by the invention has good thermal shock resistance and bending strength after being sintered.

A high-entropy nano-array for electrocatalytic nitrate reduction coupling waste plastic conversion is prepared by the following method: (1) immerse the nickel foam into a hydrochloric acid solution to remove the surface oxide layer and oil stains, rinse with deionized water / ethanol three times, and dry for subsequent use; (2) solid powders of sodium chloropalladate, platinum acetylacetate, nickel chloride hexahydrate, copper chloride dihydrate, silver trifluoroacetate and tungsten hexacarbonyl are poured into an N-N dimethylformamide solution, ultrasonic is used to dissolve the solid powders, then glacial acetic acid and the treated nickel foam are added to the above solution, and after ultrasonic, heating in an oven is carried out, after the reaction is completed, water and ethanol solution are used for alternate washing, and drying is carried out, and the high-entropy nano-array catalyst is obtained. A preparation method of a high-entropy nano-array for electrocatalytic nitrate reduction coupling waste plastic conversion is provided. The high-entropy nano-array has excellent electrocatalytic activity and stability.

The application discloses a lithium-free high-heat-resistant ceramic mud and a preparation method thereof, and relates to the technical field of ceramic materials. In the preparation of the lithium-free high-heat-resistant ceramic mud, alumina is reacted with 3-(2,3-epoxypropoxy) propyl trimethoxysilane to obtain pre-modified alumina; the pre-modified alumina is reacted with starch to obtain modified alumina; ethyl acetoacetate, isopropyl alcohol, zirconium oxychloride, aluminum sec-butoxide, polyvinylpyrrolidone and N-N dimethylformamide are mixed to form a spinning solution, the spinning solution is electrospun, and then immersed in yttrium oxide sol to obtain alumina-zirconia-yttria composite fibers; the modified alumina, talc, alumina-zirconia-yttria fibers, hydroxypropyl methyl cellulose, glycerol, oleic acid, polyethylene glycol and water are stirred and mixed, and vacuum pugging is carried out to obtain the lithium-free high-heat-resistant ceramic mud. The lithium-free high-heat-resistant ceramic mud prepared by the application has good thermal shock resistance and bending strength after sintering.

The application discloses a kind of methods for synthesizing MOFs / cellulose aerogel composite electrode material and its electrocatalytic oxygen evolution application, belong to electrocatalytic functional material preparation process technical field.It is specifically disclosed a kind of preparation method of Cr-NiFe MOF / cellulose aerogel electrode material, including the following steps, Cr source, Ni source and Fe source are dissolved in deionized water and are added to the solution of N,N dimethylformamide containing terephthalic acid, after stirring uniformly, transfer to Teflon reaction kettle, 160 DEG C is reacted 24h and obtains Cr-NiFe MOF;Subsequently, the obtained Cr-NiFe MOF powder is dispersed in carboxymethyl cellulose solution, a certain amount of acetone is added, after mixing uniformly at 80 DEG C, liquid nitrogen freezing is carried out, then 48h of freeze drying can be obtained Cr-NiFe MOF / cellulose aerogel composite material.This composite electrode material when used as electrocatalytic oxygen evolution material, show superior activity and extremely high stability.Especially, at 10mA·cm-2, show 235mV of low overpotential, tafel slope is 53.7mV·dec-1, stability is more than 210h, is one of the best aerogel composite materials of catalytic performance at present, has good application prospect in catalysis and energy conversion field.

The invention discloses a preparation method and application of Zr-MOF modified magnetic straw biochar filler, and belongs to the technical field of water pollution treatment and ecological remediation, the method comprises the following steps: adding powdery straw into a solution of ferrous ions and ferric ions, stirring and performing ultrasonic treatment, and performing high-temperature pyrolysis on the dried powdery straw to prepare magnetic biochar; zirconium salt, the magnetic straw biochar and terephthalic acid are added into an N, N-dimethylformamide solution, the mixture is stirred and subjected to ultrasonic treatment, then the mixture is put into a polytetrafluoroethylene reaction kettle for a reaction, after the reaction is finished, N, N-dimethylformamide and absolute ethyl alcohol are used for cleaning, and after drying, the Zr-MOF modified magnetic straw biochar filler is obtained. Plant straw is used as a biochar raw material, biochar is modified through Zr-MOF and ferric salt, the porous structure and the specific surface area of the Zr-MOF modified magnetic straw biochar filler can be remarkably improved, the structural stability and the adsorption activity of the filler can be enhanced, refractory organic pollutants in a water body are efficiently removed, and soil pollutants are adsorbed and fixed.

The invention provides an anti-adhesion coating suitable for low-medium-high viscosity liquid as well as a preparation method and application of the anti-adhesion coating. The preparation method comprises the following steps: taking polyvinylidene fluoride (PVDF) as a main component, doping two types of modified SiO2 particles as a filler, taking amine-terminated polyether D230 as a molecular bridging substance, taking a mixed solution of N-N dimethyl formamide (DMF) and N-methyl-2-pyrrolidone (NMP) as a solvent, combining a sol-gel method with a spraying process, and combining a non-solvent induced phase separation (NIPS) strategy to obtain the anti-adhesion coating. According to the preparation method, the viscosity threshold value of a traditional coating capable of repelling liquid is broken through through multi-scale structural design, mutual repulsion between PVDF and modified SiO2 particles which are weak in polarity is converted into stable C-N-F bonding effect through introduction of an active amino-terminated D230 molecular bridge material, the bottleneck that a traditional system structure is unstable is broken through, and the preparation method is suitable for large-scale preparation of PVDF / modified SiO2 / PVDF composite coating. The prepared broad-spectrum anti-adhesion coating has broad-spectrum anti-adhesion range, mechanical stability and chemical durability, and can be widely applied to a plurality of fields, especially the occasions of filling, storage, mixing, conveying and the like related to high-viscosity liquid.

The application discloses a hyperbranched magnetic modified MOFs-based composite material and a preparation method and application thereof, and the preparation steps of the hyperbranched magnetic modified MOFs-based composite material include the following steps: preparing a magnetic Fe3O4 magnetic material or purchasing a commercially available one; preparing a Zn-MOF material by using sodium hydroxide, trimesic acid, N-N dimethylformamide, ethanol and zinc acetate dihydrate; preparing a carboxyl-terminated hyperbranched polymer by using diethanolamine, methanol, methyl acrylate, trimethylolpropane, p-toluene sulfonic acid and maleic anhydride; and reacting the magnetic Fe3O4 with the Zn-MOF and the carboxyl-terminated hyperbranched polymer to obtain the hyperbranched magnetic modified MOFs-based composite material. The hyperbranched magnetic modified MOFs-based composite material prepared by using the application can remove the chroma in water, can realize the effect of low dosage and high removal rate, and has stable recycling regeneration effect and high removal efficiency.

The application belongs to the technical field of polymer materials, and discloses a method for preparing a polyamide nanofiltration membrane based on a non-reactive ionic liquid, which comprises the following steps: preparation of a substrate PES membrane: 16wt% of polyethersulfone PES, 16wt% of polyethylene glycol PEG, and 68wt% of N-N dimethylformamide DMF are weighed and placed in a round-bottom flask, stirred in a water bath, and left to stand at the same temperature to remove air bubbles, then, the casting solution is cast on a glass plate with a steel knife and immersed in ultrapure water to remove residual solvent; preparation of a polyamide PA membrane: interfacial polymerization is performed on the PES membrane by using an aqueous phase solution containing piperazine PIP and 1-butyl-3-methylimidazole chloride and an oil phase solution containing TMC to synthesize a polyamide active layer. The application provides a new perspective for the regulation of monomer diffusion and reaction in the interfacial polymerization process, and has important application potential in the preparation of high-performance polyamide composite membranes.

A graphene-coated V3S4@NC material and a preparation method therefor and the use thereof. The material is composed of V3S4@NC and graphene coated on the surface of V3S4@NC, wherein V3S4@NC is of a core-shell structured nanofiber composite material with a V3S4 core and an NC shell. The method comprises the following steps: step I: adding a sulfur powder, vanadyl acetylacetonate (VO(acac)2), polyacrylonitrile (PAN), and graphene oxide to N-N dimethylformamide (DMF), stirring same for 12 h, followed by ultrasonic oscillation to obtain a mixed solution; step II: filling a syringe with the mixed solution obtained in step I, performing electrostatic spinning at a flow rate of 0.4 mL / h under a voltage of 18 kV, and collecting a product, so as to obtain a precursor; and step III: placing the collected precursor in a protective atmosphere, and annealing same at 800 ºC for 3 h to obtain a graphene-coated V3S4@NC material. The product can enable the reduced transport distance of sodium ions, and improvement of the electrochemical performance thereof.

The application belongs to the technical field of plastic materials, and particularly relates to a prosthesis material for orthopedics and a preparation method thereof. The preparation method comprises the following steps: (1) pretreating carbon fibers to obtain pretreated carbon fibers; (2) modifying the carbon fibers by using KH792 to obtain silane-modified carbon fibers; (3) mixing the silane-modified carbon fibers and N,N dimethylformamide, continuously adding polyethylene glycol diacetate and a condensing agent, heating and reacting, and removing the N,N dimethylformamide by rotary evaporation to obtain modified carbon fibers; and (4) uniformly mixing PEEK powder, the modified carbon fibers and carboxylated carbon nanotubes, and performing mold pressing to obtain the prosthesis material for orthopedics. The prosthesis material for orthopedics prepared by the application is safe to use, has high mechanical properties and good fatigue resistance.

The application discloses a near-infrared fluorescent probe, a preparation method and application thereof, and has the structure shown in compound 1. The fluorescent probe prepared by the preparation method has strong ultraviolet in the near-infrared region; and can rapidly and efficiently detect cysteine in a mixed solution formed by N,N dimethylformamide and water and generate a new absorption peak at 750 nm. The fluorescent probe prepared by the preparation method has strong fluorescence in the near-infrared region; and can rapidly and efficiently detect cysteine in a mixed solution formed by N,N dimethylformamide and water and generate a new absorption peak at 750 nm.

The application discloses a method for detecting rhodamine B by using solvent-induced fluorescence enhancement. The method synthesizes up-conversion nanoparticles NaYF4:20%Yb,2%Er@NaYF4:30%Nd (UCNPs) with small particle size, uniform size and good water solubility by a thermal decomposition method, and the up-conversion nanoparticles can emit 541 nm fluorescence under the excitation of 808 nm light and the fluorescence is absorbed by rhodamine B. A simple, stable, rapid and high-sensitivity method for detecting rhodamine B based on fluorescence enhancement of the up-conversion nanoparticles is established by changing the medium environment of the UCNPs by using a mixed solvent of N,N dimethylformamide and water. The method is simple in operation, high in selectivity and fast in response speed, and is successfully applied to tomato sauce actual samples.