1734 results about "Carbon nitride" patented technology

The invention belongs to the technical field of battery positive electrode materials, and discloses a tellurium and niobium doped and carbon nitride coated positive electrode material and a preparation method thereof, the chemical formula is LiNi < x > Co < y > Mn < 1-x-y-u-v > Te Nb < v > O < 2 > at C < 3 > N < 4 >, x is greater than or equal to 0.5 and less than or equal to 0.98, 0 lt; yt; Yt; 0, 0.5, 0 lt; u < = 0.1, 0lt; v < = 0.1, 1-x-y-u-vgt; 0. A Te / Nb co-doping mode is adopted, and Te and Nb are synergistically modified, so that the crystal structure of the material is stabilized, and good mechanical stability and cycle performance of the material are kept; lithium ions migrated on the surface of the positive electrode material and carbonate on the surface of the material are inhibited from forming lithium carbonate, so that the technical problem of battery gas expansion is solved; the carbon nitride coating provides additional transmission channels and adsorption sites for lithium ions, reduces the interface resistance at the same time, contributes to faster migration of the lithium ions under a low-temperature condition, and improves the first coulombic efficiency, the rate and the cycle performance of the battery at a low temperature.

The invention belongs to the field of sodium ion batteries, and particularly discloses a positive electrode material and a preparation method and application thereof. The positive electrode material is carbon nitride coated fluorine-doped pyrophosphate sodium manganese iron phosphate, the chemical formula of the positive electrode material is NaaFe3-bMnb (PO4-x) 2F4xP2O7 / C3N4, a is larger than or equal to 3.95 and smaller than or equal to 4.1, b is larger than or equal to 0.3 and smaller than or equal to 2.4, and x is larger than or equal to 0.005 and smaller than or equal to 0.05. The sodium ferromanganese pyrophosphate is subjected to fluorine doping and carbon nitride coating, so that the electronic conductivity and the structural stability of the sodium ferromanganese pyrophosphate can be improved, the capacity of the sodium ferromanganese pyrophosphate can be well exerted, and the capacity and the voltage platform of the sodium-ion battery are improved.

The invention provides a low-cost metal modified electrode material, a preparation method and application, solves the problems that a carbon nitride material is difficult to recover and poor in sustainability, and improves the photoelectrocatalysis capability of an active carbon material. Further constructing a packed bed cathode coupled microbial fuel cell system; the treated industrial wastewater is high-salt coking wastewater from Anshan steel, a PEC-MFC system filled with electrogenesis microorganisms is used for realizing wastewater recycling and harmlessness, and energy-saving, high-efficiency and one-step treatment of the industrial wastewater is completed.

The invention provides a lithium manganese iron phosphate material as well as a preparation method and application thereof. The lithium manganese iron phosphate material sequentially comprises a lithium manganese iron phosphate matrix inner core, a first coating layer and a second coating layer from inside to outside, the first coating layer comprises a carbon material, the second coating layer comprises a composite material, and the composite material comprises carbon nitride and a conductive polymer. Through doping and coating of the carbon material in the first coating layer and synergistic cooperation of the conductive polymer and the carbon nitride in the second coating layer, the conductivity of the lithium manganese iron phosphate material is improved, and the cycling stability, the capacity and the rate capability of the lithium manganese iron phosphate material are improved.

The invention relates to the technical field of nano-enzymes, in particular to a Fe monatomic / Pt nano-cluster nano-enzyme as well as a preparation method and application thereof. The invention relates to a preparation method of Fe monatomic / Pt nanocluster nano-enzyme, which comprises the following steps: dispersing graphite phase carbon nitride in water, adding polyphenol and amine, stirring for 10-14 hours, carrying out suction filtration, and drying to obtain a polyphenol amine coated graphite phase carbon nitride precursor; dispersing the graphite-phase carbon nitride precursor in water, adding an iron source and a platinum source, stirring for 10-14 hours, and performing suction filtration, drying, carbonization, acid pickling, centrifugation and drying to obtain the Fe monatomic / Pt nanocluster nanoenzyme. The Fe monatomic / Pt nanocluster nano-enzyme is prepared by the method disclosed by the invention. The invention relates to an application of a Fe monatomic / Pt nanocluster nano-enzyme in pesticide detection. Compared with a single Fe monatomic or Pt nanocluster nano-enzyme, the Fe monatomic / Pt nanocluster nano-enzyme provided by the invention can generate a synergistic effect and has higher catalytic activity.

Methods of filling a feature with large grain tungsten include deposition of a tungsten carbon nitride (WCN) or tungsten nitride (WN) film that lines the feature. The WCN or WN film may be treated. It provides a template for subsequent growth of large grain tungsten. The top of the feature is treated with nitrogen to inhibit nucleation, facilitating bottom-up growth. In some embodiments, single grain tungsten is grown from the bottom up. Methods of at least partially filling a feature with single grain tungsten include treatment of the feature. In some embodiments, single grain tungsten is grown without a liner layer in the feature.

The invention belongs to the technical field of electrochemistry, and particularly relates to a gas diffusion electrode for efficiently producing hydrogen peroxide in situ and a preparation method thereof. The gas diffusion electrode is composed of a carbon paper substrate, a carbon black gas diffusion layer and a carbon nitride modified carbon nanotube catalyst layer. The preparation method of the gas diffusion cathode comprises the following steps: mixing a carbon nanotube, g-C3N4, isopropanol, 60wt% of PTFE emulsion and water to prepare a mixed solution, and loading a compound of the carbon nanotube and g-C3N4 on one side of a carbon paper substrate by adopting an ultrasonic impregnation mode to prepare a catalyst layer; the other side of the carbon paper substrate is impregnated with carbon black and PTFE emulsion to prepare a diffusion layer, and the diffusion layer is uniformly coated, dried and annealed to prepare the gas diffusion cathode. The gas diffusion electrode is used for efficiently producing hydrogen peroxide through in-situ electrocatalysis, the yield of hydrogen peroxide can reach 1050 mg / L after 1.5 h, the current efficiency is 76%, and the energy consumption is 5.56 KWh / Kg.

A method of adsorption includes contacting a nanocomposite with a solution including one or more pollutants. The nanocomposite is a graphite-phase carbon nitride copper oxide and magnesium aluminum oxide (g-C3N4@CuO / MgAl2O4) material and includes a graphite-phase carbon nitride (g-C3N4) in an amount of 5 to 15 percent by weight (wt. %), copper oxide in an amount of 3 to 7 wt. %, and magnesium aluminum oxide (MgAl2O4) in an amount of 80 to 90 wt. % based on a total weight of the g-C3N4@CuO / MgAl2O4 material. The method further includes adsorbing the one or more pollutants on the nanocomposite.

The invention relates to a preparation method of a copper-doped carbon nitride nano composite material and application of the copper-doped carbon nitride nano composite material in electrocatalytic carbon dioxide reduction. The preparation method comprises the following steps: firstly, preparing a carbon nitride precursor, taking salt of metal copper as a source of the metal copper to obtain a copper-doped carbon nitride nano composite material, and applying the copper-doped carbon nitride nano composite material to electrocatalytic reduction of carbon dioxide to obtain ethanol. Results show that in a wide voltage range, the catalytic performance of the catalyst is obviously improved, which is mainly characterized in that lamellar graphite carbon nitride is used as a substrate, existence of pyridine nitrogen is beneficial to activation of carbon dioxide to generate CO *, copper in a monatomic form can promote a C-C coupling process, and then a multi-carbon product ethanol is generated; and the lamellar morphology can utilize catalytic active sites to the greatest extent, so that the catalytic performance is greatly improved.

The invention discloses a photocatalyst antibacterial hydrogel-based fresh-keeping material as well as a preparation method and application thereof, and belongs to the technical field of fresh-keeping materials. The photocatalyst antibacterial hydrogel-based fresh-keeping material is prepared from the following raw materials in parts by mass: 180 to 220 parts of water, 1 to 6 parts of graphite-phase carbon nitride, 10 to 20 parts of polyvinyl alcohol, 1 to 3 parts of carboxymethyl chitosan and 8 to 12 parts of tannic acid. The invention further discloses a preparation method of the photocatalyst antibacterial hydrogel-based fresh-keeping material and application of the photocatalyst antibacterial hydrogel-based fresh-keeping material in fruit fresh keeping. The photocatalyst antibacterial hydrogel-based fresh-keeping material disclosed by the invention solves the problems of potential toxicity, easiness in inactivation, poor fresh-keeping effect and poorer mechanical property of an existing fresh-keeping material, realizes long-time effective fresh keeping of high-moisture fruits, does not involve chemical reaction in the preparation process, is non-toxic, easily available and degradable in raw materials, and has excellent environmental friendliness.

The invention relates to a K / O co-doped and cyano-grafted graphite phase carbon nitride material as well as a preparation method and application thereof. The material comprises three defect types, namely a C-O-C bond formed by a C-N = C bond in an oxygen substituted triazine skeleton, potassium ions existing between layers and cyano groups generated by protonation of amino groups at the edge. According to the material disclosed by the invention, K ions are doped into the g-C3N4 layer to form K-N bridge connection between layers, the material can be used as an electron channel to effectively accelerate electron migration, cyano groups at the edge have relatively strong electron-withdrawing capability and can be used as sites for adsorbing hydrogen ions, and introduced oxygen can be used as active sites for producing H2O2. The three components cooperate with each other to effectively promote transmission of photo-induced electrons and separation of photo-induced electron hole pairs, so that the photocatalytic effect is remarkably improved, and the photocatalyst is an efficient photocatalyst with excellent performance.

The invention relates to the technical field of lead-acid batteries, and discloses a negative electrode additive for a lead-acid battery and a preparation method of the negative electrode additive. The negative electrode additive is a composite material prepared by compounding SnO2, COF and a carbon nitride nanotube, the composite material is SnO2 coated COF coated porous carbon nitride nanotube, and the addition amount of the negative electrode additive is 0.25% of the mass of the negative electrode lead powder of the lead-acid battery; the SnO2 (at) COF (at) porous carbon nitride nanotube is added, so that the sulfation phenomenon of the negative electrode of the lead-acid battery is effectively improved, the high-rate partial charge state of the lead-acid battery is improved, the cycle life of the battery is further prolonged, the hydrogen evolution overpotential of the negative electrode plate is also improved, the precipitation of hydrogen is reduced, and the service life of the battery is prolonged. Furthermore, the water loss of the electrolyte, the increase of the internal pressure of the battery and the impact on the electrode plate can be effectively relieved, and the stability of the electrode plate and the battery is favorably maintained, so that the use performance of the battery is improved.

The invention relates to a high-flame-retardant, high-thermal-conductivity and high-toughening epoxy resin packaging adhesive and a preparation method thereof. A self-developed flame retardant containing nitrogen, phosphorus and sulfur is added into an epoxy resin system, rich carbon residues hinder mass and heat exchange in the combustion process and also hinder combustible gas from being released to a combustion area, free radicals containing phosphorus and sulfur can capture active free radicals (H * and OH *), and the chain reaction of combustion is ended. The surface modifier is used for modifying the layered graphene composite boron nitride micro-powder heat-conducting filler, so that the interface interaction between the filler and the resin matrix is synergistically enhanced, and the compatibility and the heat-conducting effect of the filler and the resin matrix are improved. And the modified toughening agent is added to ensure that the epoxy resin packaging adhesive has good toughness. In addition, through further exploration and innovation, the specific proportion range of the nitrogen-phosphorus-sulfur flame retardant, the modified layered graphene composite carbon nitride micro powder and the flexibilizer is determined. The epoxy resin packaging adhesive prepared by the invention has excellent flame retardance, heat conductivity and toughness.

The invention is suitable for the technical field of flame retardance of high polymer materials, and provides a core-shell structure graphite phase carbon nitride derivative and a preparation method thereof.The derivative is prepared by the steps that a precursor containing phosphorus and boron elements is mixed with melamine, and phosphorus / boron co-doped graphite phase carbon nitride is prepared through a high-temperature thermal polymerization reaction; and then assembling the phytic acid copper on the surface of the graphite-phase carbon nitride in an in-situ growth manner by adopting an aqueous solution self-assembly method to construct a derivative with a core-shell structure. The invention provides the graphite phase carbon nitride derivative with the core-shell structure, which is green, environment-friendly, efficient and flame-retardant and simple and convenient in process, and the preparation method of the graphite phase carbon nitride derivative, and the graphite phase carbon nitride derivative has wide application prospect and industrialization value.

The invention relates to the technical field of composite catalyst materials, in particular to a ferrocobalt bimetal hydroxide / BCN composite material and a preparation method and application thereof.The preparation method comprises the steps that cobalt nitrate and ferric nitrate are used for preparing a metal salt solution, sodium carbonate and sodium hydroxide are used for preparing a precipitant solution, a B-doped carbon nitride BCN material is added into the metal salt solution to form a uniform suspension, and the suspension is dried to obtain the ferrocobalt bimetal hydroxide / BCN composite material; dropwise adding the precipitant solution into the suspension to obtain a precursor solution, performing hydrothermal reaction on the precursor solution, and performing centrifugal impurity removal and drying to construct a heterostructure between layered double hydroxide and BCN in situ to obtain the Co-Fe LDH-coated BCN composite material. Through boron doping and heterostructure construction, the charge separation capacity of graphite carbon nitride is enhanced, the electron migration efficiency is improved through a heterointerface structure, the metal ion release amount and the cycle stability are controlled, and the catalytic performance is remarkably improved.

The invention relates to a preparation method and application of a cobalt-doped porous carbon nitride nanosheet, and the preparation method comprises the following steps: (1) taking a nitrogen source and a cobalt source as raw materials, grinding the nitrogen source and the cobalt source, uniformly mixing, calcining at high temperature, naturally cooling to room temperature, washing the calcined substances of the nitrogen source and the cobalt source, and drying in vacuum to obtain the cobalt-doped carbon nitride nanosheet; and (2) dispersing the cobalt-doped carbon nitride nanosheet obtained in the step (1) in hydrazine hydrate for heating reaction, washing the cobalt-doped carbon nitride nanosheet to be neutral after the heating reaction is finished, and finally performing vacuum drying to obtain the cobalt-doped porous carbon nitride nanosheet. The cobalt-doped porous carbon nitride nanosheet prepared by the method disclosed by the invention is a catalytic material which is high in response capability to visible light, high in yield of hydrogen peroxide prepared by photocatalysis, good in decomposition inhibition performance and capable of being repeatedly used, and is suitable for the field of new energy products.

The invention discloses a carbon nitride nanoflower photocatalyst assembled by nanosheets as well as a preparation method and application thereof, and relates to the technical field of photocatalytic materials. The method comprises the following steps: firstly, obtaining a supramolecular intermediate through a hydrothermal method, and calcining the supramolecular intermediate through a muffle furnace to obtain carbon nitride nanoflowers assembled by nanosheets; the nanosheet-assembled carbon nitride nanoflower has abundant edge active sites and a shorter electron transfer path, and meanwhile, the unique electronic structure of the nanosheet-assembled carbon nitride nanoflower is beneficial to expansion of absorption of visible light, so that the problems of few exposed active sites, low carrier separation rate, low visible light utilization rate and the like of an existing photocatalyst are solved; therefore, the photocatalytic activity is improved. The photocatalyst prepared by the invention can efficiently and stably generate H2O2 in pure water under the condition of visible light.

The invention discloses a carbon nitride-based composite material as well as a preparation method and application thereof. The carbon nitride-based composite material comprises a non-metal doped carbon nitride carrier and a noble metal, wherein the noble metal exists in the carrier in an element doping form and / or is loaded on the carrier in an oxide form; the precious metal is one or more of Pt, Pd, Au and Ru, and the nonmetal is one or more of P, S and I. According to the carbon nitride composite material disclosed by the invention, noble metal is utilized to modify carbon nitride, the number of surface active sites is increased, the electron and chemical structures of an active center are adjusted, and meanwhile, generation and migration of photo-generated charges are promoted. Meanwhile, the surface of the carbon nitride composite material is modified by non-metallic elements, so that adsorption and activation of reactant H2O molecules are effectively promoted. The catalyst disclosed by the invention is simple in preparation process, good in repeatability and easy for large-scale production.

The invention discloses preparation and application of carbon nitride / titanium carbide / amidoxime-based gel, and relates to preparation and application of a carbon nitride composite titanium carbide composite amidoxime-based hydrogel material. The invention provides the preparation method of the amidoxime-based hydrogel which is simple in synthesis, high in adsorption speed and high in efficiency. The design of the hydrogel material with high-speed uranium adsorption and green uranium circulation has important significance for realizing seawater uranium circulation, wherein the adsorption and desorption functions and the design of the mechanism thereof are key. According to the preparation method, the two-dimensional PAO / TiC / CN hydrogel is prepared by compounding PAO nanoparticles with a selective adsorption function and a two-dimensional TiC-CN photocatalyst. The hydrogel has a porous structure and cannot be damaged after being soaked in water for more than six months.

The invention provides a boron-doped carbon nitride-based cobalt monatomic catalyst and a preparation method and application thereof.The boron-doped carbon nitride-based cobalt monatomic catalyst is prepared from a boron-doped carbon nitride material of a lamellar structure, cobalt monatomic and lamellar boron carbon nitride form unique coordination, boron-cobalt lean and rich electron double sites are constructed, persulfate is driven to be subjected to reduction and oxidation reactions at the same time, and the catalyst is prepared. An efficient free radical and non-free radical synergistic system is constructed, and the boron carbon nitride based monatomic catalyst has excellent performance in degradation of carbamazepine and degradation of various organic pollutants.

The invention belongs to the technical field of aqueous zinc ion batteries, and discloses a preparation method and application of an aqueous zinc ion battery negative electrode coating material. The composite material is a silver-loaded carbon nitride composite material, and the composite material is used as a water-based zinc ion battery negative electrode artificial interface layer. A silver-loaded carbon nitride composite nano material is used as a zinc negative electrode interface coating. Silver nano ions can effectively improve electrostatic shielding on the surface of the zinc negative electrode, zinc ions are easier to deposit, and growth of zinc dendrites is inhibited; the material has excellent mechanical strength and chemical stability, so that the corrosion of electrolyte to the negative electrode is effectively inhibited; the protective layer is simple in preparation process, the prepared coating is high in adhesive force, a stable interface layer is easy to form, the half-cell cycle efficiency stability is obviously improved, the half-cell can stably circulate for 1323 circles, and the service life of the water-based zinc ion battery is prolonged.

The invention is suitable for the technical field of photocatalyst preparation, and provides a modified tubular g-C3N4 loaded Ni-CoP photocatalyst and a preparation method thereof. The preparation method comprises the following steps: calcining a carbon nitride precursor in stages to obtain tubular carbon nitride, stirring the tubular carbon nitride with a cobalt and nickel-containing compound and an alkaline compound, washing and drying to obtain a precipitate, calcining, mixing and grinding with a phosphorus-containing compound, calcining again, and modifying the product with polydopamine and polypyrrole to obtain the composite material. The photocatalyst modified by the polydopamine and the polypyrrole and loaded with the Ni-CoP by taking the tubular g-C3N4 as the carrier is obtained. According to the invention, three-in-one synergistic integration of'carrier-modifier-cocatalyst 'is realized, the prepared photocatalyst still keeps tubular morphology and has a larger specific surface area, the requirements of anode oxygen evolution reaction (OER) on rapid charge separation and transmission can be met, meanwhile, the light absorption range is widened, the solar energy utilization rate is increased, and a foundation is laid for efficient OER reaction.

The invention discloses a cobalt-rhodium-doped nitrided activated carbon supported composite catalyst and a preparation method thereof, and application of the catalyst in preparation of aldehyde by catalyzing olefin, especially application of diisobutylene in preparation of isononanal. In the composite catalyst, the content of Rh is 0.2-1.5 wt% in terms of Rh atoms, the content of Co is 0.1-0.8 wt% in terms of Co atoms, the mass ratio of Co to Rh is 10: 1-1: 1, preferably 2: 1, and Co and Rh exist in the form of nanoclusters or monatomic atoms and are connected to a carbon nitride skeleton structure in the form of covalent bonds. According to the composite catalyst, the structure mainly comprises micropores and is provided with a small number of mesopores and macropores, the adsorption capacity of the material is enhanced, meanwhile, the material belongs to a heterogeneous catalytic material, the technical problem that the material is difficult to recycle is solved, cyclic utilization is facilitated, and the use cost is reduced. The catalyst can realize high-efficiency hydroformylation of diisobutylene to prepare isononanal, can be recycled and has an industrial application prospect in the aspect of olefin hydroformylation.

The invention provides a preparation method of a TiO2 / Au-C3N4 heterojunction photoelectrochemical biosensor and an application of the TiO2 / Au-C3N4 heterojunction photoelectrochemical biosensor. Comprising the following steps: step 1, preparing TiO2 / FTO; step 2, preparation of TiO2 / Au-C3N4 (titanium dioxide / Au-C3N4); step 3, preparing a nucleic acid aptamer; and step 4, using the confining liquid mercaptohexanol. The preparation method comprises the following steps: firstly, preparing a TiO2 thin film by an electrophoretic deposition method, and then combining the TiO2 thin film with graphite phase carbon nitride (g-C3N4) doped with high-conductivity noble metal gold nanoparticles (Au NPs) to form a heterojunction; under an illumination condition, Au NPs and photons interact to generate a regional surface plasma resonance phenomenon, and a strong electromagnetic field and high-concentration high-energy carriers are formed on the surface of the nano structure in the process, so that the photocurrent response of the composite material is remarkably enhanced; besides, the introduced Au NPs can also form an Au-S bond with the DNA aptamer containing the-SH group, and more binding sites are provided, so that the capture capability of the aptamer is enhanced.

The invention belongs to the technical field of immunoassay and biosensing detection, and particularly relates to a preparation method and application of an antibiotic electrochemical luminescence sensor based on a double-enhancement strategy. According to the invention, a bifunctional metal organic gel is used as a substrate, a graphite-phase carbon nitride quantum dot is used as a luminous body, and a self-assembly split aptamer walker is combined to construct the electrochemical luminescence sensor for sensitive detection of antibiotics. The sensor has the advantages of extremely high specificity and sensitivity, wide detection range, low detection limit and strong anti-interference performance, and has important scientific significance and application value in detection of antibiotic residues in the environment.

The invention provides a preparation method of a nanofiltration membrane for regulating and controlling interfacial polymerization reaction by utilizing carbon nitride photogenerated charge, and belongs to the technical field of water treatment membranes. The preparation method comprises the following steps: (1) adding carbon nitride film-making sol into an aqueous solution of a polyamine monomer, and carrying out ultrasonic dispersion to obtain a mixed dispersion liquid; (2) preparing an organic phase monomer solution; (3) adding an ultrafiltration support base membrane into the mixed dispersion liquid, infiltrating, then taking out, adding into the organic phase monomer solution, and carrying out interfacial polymerization reaction to obtain a high-permeability membrane containing an ultrathin polyamide separation layer; wherein the infiltration and the interfacial polymerization reaction are carried out under illumination; and (4) carrying out heat treatment on the high-permeability membrane containing the ultrathin polyamide separation layer to obtain the nanofiltration membrane. According to the preparation method disclosed by the invention, the photoelectrochemical characteristics of carbon nitride are utilized, and electrostatic repulsion exists between positive charges on the surface of carbon nitride and piperazine molecules under illumination, so that the interfacial polymerization rate is regulated and controlled, and the high-permeability nanofiltration membrane with an ultrathin polyamide separation layer is further prepared.

The invention belongs to the technical field of ceramic materials, and relates to complex-phase high-entropy ceramic as well as a preparation method and application thereof. The technical problem that in the prior art, high-entropy ceramic cannot synchronously have high hardness and fracture toughness is solved. The invention provides a complex-phase high-entropy ceramic. The complex-phase high-entropy ceramic comprises a carbonitride phase and a single boride phase, the transition metal elements comprise titanium, zirconium, niobium, tantalum and hafnium; in the complex-phase high-entropy ceramic, calculated according to the volume content, 93Vol% is smaller than or equal to the carbonitride phase lt; 100 Vol%, 0 Vol% lt; and the single boride phase is less than or equal to 7Vol%. The complex-phase high-entropy ceramic has the advantages of uniform two-phase distribution, small grain size, high density, high hardness and high fracture toughness. The invention further provides a preparation method of the complex-phase high-entropy ceramic, a liquid-phase precursor method is combined with an in-situ hot pressing sintering method, the process is simple, and the production period is short. Meanwhile, the invention further provides application of the complex-phase high-entropy ceramic in material preparation in the fields of aerospace and mechanical engineering.

The invention discloses a preparation method of a porous few-layer carbon nitride / amidoxime-based seawater uranium extraction composite material with a multilevel structure, and relates to the field of seawater uranium extraction materials. The composite material is a porous few-layer carbon nitride material with high photocatalytic performance obtained by repeatedly calcining melamine at a high temperature; polyacrylonitrile is subjected to amidoxime functionalization, and a polyamidoxime solution is obtained; uniformly dispersing porous few-layer carbon nitride in the polyamidoxime solution, and adding a sacrificial pore-forming agent polyvinylpyrrolidone at the same time to obtain a spinning solution; and finally, preparing the porous few-layer carbon nitride / amidoxime-based seawater uranium extraction composite material with high adsorption performance by utilizing a one-step electrostatic spinning technology. The obtained composite material has excellent uranium adsorption performance and adsorption rate and can be recycled, the preparation method is simple in process and free of pollution to the environment, and the prepared composite material has excellent uranium adsorption performance and adsorption rate, can be recycled and has wide application prospects in the field of uranium extraction from seawater.

The invention relates to the technical field of electrode paste, in particular to electrode paste for a submerged arc furnace and a preparation method of the electrode paste. Comprising three-level grain size distribution anthracite aggregate which is electrically calcined at high temperature and modified by a KH-550 silane coupling agent, a modified silicon carbide whisker and boron-doped graphene-like carbon nitride composite filler, a maleic anhydride-mediated compatible medium-temperature pitch-polyborosiloxane binder and a graphite powder-borax functional additive. A step-by-step mixing and two-stage sintering process is adopted in the preparation process, a covalent bond interface bridging structure is constructed through the coupling agent, the composite dispersing agent regulates and controls the multi-dimensional network distribution of the filler, and the process synergistically improves the compactness and the interface bonding force of the green body. The electrode paste is firm in interface bonding, can form a ceramic protective phase at a high temperature, has excellent conductivity and mechanical strength, and prolongs the service life of the electrode paste for the submerged arc furnace.

The invention relates to a method for preventing and controlling antibiotic and drug-resistant gene transmission in a soil vegetable system based on a charcoal-based composite material. According to the invention, agricultural waste corn straw is used as a precursor, magnetic iron and graphite phase carbon nitride are loaded through a hydrothermal reaction, and then high-temperature calcination is carried out to prepare a FeBC / g-C3N4 (short for FeBC / g-CN) biochar composite material which is used as a soil conditioner. The prepared biochar modifier is applied to polluted farmland soil to be treated, sufficient and uniform mixing is conducted, vegetable seeds are sown, illumination is provided, and a certain water content of the soil is kept, the prepared biochar modifier is simple in preparation method and application method and remarkable in effect, the reduction rate of tetracycline in soil vegetables is increased through use of the biochar modifier, and the soil quality is improved. Meanwhile, transmission of antibiotics and drug-resistant genes in a soil vegetable system is blocked and controlled.