56 results about "Cobalt ferrite" patented technology

The invention discloses a sodium alginate embedded iron-carbon microcapsule material for repairing cadmium and arsenic polluted soil and a preparation method of the sodium alginate embedded iron-carbon microcapsule material, and belongs to the technical field of soil heavy metal pollution repairing materials. The material comprises straw biochar, high-iron steel slag powder, a sulfydryl acetylated chitosan-iron monatomic cluster compound, a boron-doped graphitized carbon coated cobalt ferrite nanosheet, sodium alginate, calcium chloride and sodium carbonate. Wherein the sulfydryl acetylated chitosan is prepared by reacting chitosan with sulfydryl acetic anhydride, dialyzing and drying, and performing solvothermal reaction with ferric nitrate under high pressure. The preparation method comprises the following steps: pyrolyzing and drying the straw biochar, reacting the high-iron steel slag with sulfuric acid, adding the biochar, adjusting the pH value, adding sodium carbonate, mixing to obtain an iron-carbon-based passivation material, mixing with two modified compounds, mixing with a sodium alginate solution, dropwise adding a calcium chloride solution, and stirring and curing. The material can be applied to remediation of cadmium and arsenic polluted soil.

Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. The cobalt ferrite particles are obtained by a method for producing cobalt ferrite particles, including performing a thermal treatment on an aqueous solution containing a divalent iron salt and a divalent cobalt salt stabilized by a complexing agent (ferrite precursor).

The application belongs to the technical field of electromagnetic shielding materials, and relates to MXene / BC@CoFe2O4 electromagnetic shielding aerogel and a preparation method thereof. The electromagnetic shielding aerogel is composed of MXene, bacterial cellulose (BC) and cobalt ferrite (CoFe2O4) grown by a co-precipitation method, contains anisotropic MXene porous structure, and BC@CoFe2O4 forms a three-dimensional magnetic network. Nano-magnetic particles CoFe2O4 are grown on bacterial cellulose by a co-precipitation method; the bacterial cellulose with the nano-magnetic particles CoFe2O4 grown thereon is mixed with a MXene dispersion liquid to occur liquid self-assembly, thereby forming an aerogel precursor; and a directional three-dimensional porous structure is formed by using a liquid nitrogen directional freezing method. The magnetic particles of the MXene / BC@CoFe2O4 electromagnetic shielding aerogel can cause magnetic loss to electromagnetic waves, the MXene with good electrical conductivity causes impedance mismatch with electromagnetic waves, reflects electromagnetic waves, and the bacterial cellulose can enhance the mechanical properties of the aerogel.

The present invention discloses a preparation method and application of a bacterial cellulose-based composite nanogenerator, belonging to the field of nanogenerator and power monitoring technology. Through solution blending technology, graphene oxide and cobalt ferrite are embedded in a bacterial cellulose matrix to prepare a composite material with a stable structure. The electromagnetic properties, triboelectric properties, and mechanical stability of each composite material are systematically evaluated to screen the optimal formulation. The composite material is used to prepare a nanogenerator, and a composite structure including a friction layer and an electromagnetic induction coil is designed. By monitoring the power fluctuations output by the nanogenerator, the real-time state of the transformer's leakage magnetic field is directly reflected. The present invention utilizes the preparation method and application of the bacterial cellulose-based composite nanogenerator to achieve self-powered monitoring of power transformers, improving the accuracy and real-time performance of leakage magnetic field detection.

This application provides a sheet-like spinel cobalt ferrite, its preparation method, and its application, belonging to the field of solid oxide battery technology. In this application, a Co source and an Fe source are dissolved in deionized water, citric acid is added and stirred until homogeneous, then heated in a water bath until the solution becomes a reddish-brown transparent gel. The gel is then dried and ground to obtain a first powder. The first powder is then subjected to two CO2 laser-induced oxidation processes in air at a laser power of x to obtain a second powder. Wherein, 4W < x ≤ 10W. Finally, the second powder is washed and dried to obtain a sheet-like spinel cobalt ferrite. Compared with ordinary spinel cobalt ferrite, using the aforementioned sheet-like spinel cobalt ferrite as a cathode material in SOFC can reduce the polarization impedance of the battery by 0.023 Ωcm. 2 The maximum power density increased by 0.38 W / cm². ‑2 This improves the oxygen reduction activity and stability of SOFCs. Furthermore, using CO2 laser-induced methods simplifies the preparation process, reduces time costs, and increases production efficiency.

This invention relates to the field of hydrogen energy technology, specifically to a photocatalytic water splitting method for hydrogen production. It addresses the problems of harsh reaction conditions, low hydrogen production efficiency, and poor catalyst cycle stability in existing photocatalytic hydrogen production methods. Specifically, it uses water as the reaction medium, adds a catalyst and an electron sacrificial agent, and achieves hydrogen production through water splitting under visible light irradiation. The catalyst is prepared from cobalt ferrite, indium zinc sulfide, and biochar, and the electron sacrificial agent is triethanolamine. This method enhances the separation and transport of photogenerated carriers through the synergistic effect of the catalyst and electron sacrificial agent, resulting in high hydrogen production efficiency, strong stability, simple process, and controllable cost. Furthermore, hydrogen energy, as a zero-carbon energy source, can replace fossil fuels, reducing pollution and carbon emissions at the source, contributing to the dual carbon goals, and providing an efficient solution for large-scale hydrogen production, possessing both industrial application and ecological environmental value.

The invention discloses a preparation method of a charcoal-loaded cobalt ferrite magnetic composite catalytic material, which is specifically implemented according to the following steps: step 1, selecting green tea as a biomass precursor, and carrying out carrier WT pretreatment; step 2, preparing a magnetic composite catalytic material of biochar loaded cobalt ferrite; step 2.1, preparing a suspension; step 2.2, preparing a solid product; step 2.3, preparing a dried precursor; and step 2.4, preparing the magnetic composite catalytic material of the biochar loaded cobalt ferrite. According to the method, the reaction rate is remarkably increased, the problem of magnetic agglomeration of active components is solved, non-free radical dominance is achieved, the anti-interference performance is high, and efficient magnetic recovery and waste utilization are achieved. The invention further discloses the magnetic composite catalytic material of the biochar loaded cobalt ferrite and application of the magnetic composite catalytic material.

The invention discloses an extraction process of chaste tree twig oil in the technical field of plant essential oil extraction. An ethanol aqueous solution is adopted for extraction, ultrasonic treatment and a composite enzymolysis technology are combined, the chaste tree twig cell structure is effectively destroyed, and the grease extraction rate is remarkably increased. And then selectively adsorbing impurities in the extracting solution by using a specially-made cobalt ferrite-deep eutectic solvent-biochar magnetic composite material, and realizing rapid separation through an external magnetic field. And the alkalescent ethanol water solution is adopted for elution, so that the structure stability of the deep eutectic solvent is protected while impurities are effectively desorbed. And finally, carrying out rotary evaporation and column chromatography refining to obtain the high-quality vitex negundo oil. The process integrates various extraction and purification technologies, has the advantages of high extraction efficiency, mild operation conditions, small environmental pollution and the like, and is particularly suitable for efficient extraction and refining of the vitex negundo oil.

This invention relates to the field of lightweight wood-plastic composite materials, specifically to an antistatic lightweight wood-plastic composite material and its preparation method, which addresses the problems of insufficient antistatic properties and high density in existing wood-plastic composite materials. The method involves mixing an antistatic agent with high-density polyethylene, extruding, cooling, crushing, and sieving to obtain an antistatic masterbatch. Modified wood flour, high-density polyethylene, maleic anhydride graft compatibilizer, antioxidant, 2-hydroxy-4-methoxybenzophenone, and γ-aminopropyltriethoxysilane are then mixed, cooled, and the antistatic masterbatch is added for further mixing. The mixture is fed into a twin-screw extruder, and cobalt ferrite-coated hollow glass microspheres are added. After extrusion, cooling, and crushing, the mixture is then subjected to secondary molding in a single-screw extruder, gradient cooling for shaping, and traction cutting to obtain the antistatic lightweight wood-plastic composite material. This material possesses excellent antistatic properties, low density, and lightweight characteristics, along with good flexural strength and impact strength, low water absorption, and excellent water resistance.

The invention discloses a polyaluminum ferric chloride flocculant as well as a preparation method and application thereof, and belongs to the technical field of sewage treatment.The preparation method comprises the steps that cobalt ferrite is loaded on the surface of nano mesoporous silica through a coprecipitation-calcination method, supported silica is obtained, then amination modification and tartaric acid modification are performed by using a silane coupling agent KH550, and the polyaluminum ferric chloride flocculant is obtained. And finally, blending the composite silicon dioxide with an aluminum salt, an iron salt and hydrogen peroxide under an acidic condition, and forming and loading a polyaluminum ferric chloride flocculation layer on the surface through in-situ hydrolytic polymerization and catalytic oxidation synergy to obtain the polyaluminum ferric chloride flocculant. Quadruple synergy of magnetic separation, catalytic oxidation, deep adsorption and enhanced flocculation is realized, and suspended matters, soluble organic matters, phosphorus and chromaticity are efficiently removed.

The invention discloses a core-shell adsorption material for recycling precious metal in acid wastewater and a production process thereof, and relates to the technical field of precious metal adsorption and separation. Polyvinylidene fluoride is used for wrapping a magnetic material cobalt ferrite to prepare a carrier with a core-shell structure, the magnetic material cobalt ferrite is used as a core, a polyvinylidene fluoride film layer is used as a shell layer, then polyethyleneimine is grafted on the surface of polyvinylidene fluoride through a chemical reaction, and the magnetic material cobalt ferrite / polyvinylidene fluoride composite material is obtained. Finally, carboxymethyl chitosan which can adsorb palladium and platinum and is friendly to microorganisms is introduced to polyethyleneimine molecules through a chemical reaction, and efficient adsorption of palladium and platinum in the acid wastewater is achieved through cooperation of polyethyleneimine, carboxymethyl chitosan and microorganisms loaded on the surfaces of the polyethyleneimine, carboxymethyl chitosan and the microorganisms.

The invention relates to a sensitive material based on a nano-foam structure and an electrochemical hydrogen sulfide gas sensor, and a preparation method of the sensitive material based on the nano-foam structure comprises the following steps: S1, weighing Co salt and Fe salt, and dissolving the Co salt and the Fe salt in water to form a mixed solution; s2, adding glucose and urea into the mixed solution, and stirring until the glucose and the urea are dissolved to obtain a clear solution; s3, baking the clarified solution, so that the glucose and the urea are subjected to a Maillard reaction, and gas is released to form a porous nano-foam structure; s4, the porous foam is annealed so that the Co salt and the Fe salt can react, then the porous foam is naturally cooled to the room temperature after annealing, the cobalt ferrite nano-foam sensitive material is obtained, the chemical formula of the cobalt ferrite nano-foam sensitive material is Co2FeO4, and the cobalt ferrite nano-foam sensitive material is used as a sensitive material of an electrochemical H2S gas sensor. According to the embodiment of the invention, high-sensitivity, low-detection-limit, high-selectivity and high-stability detection of H2S can be realized.

The application relates to a cobalt ferrite nanometer magnetic material with high magnetic permeability and low loss and a preparation method thereof, and belongs to the technical field of nanometer magnetic materials. The cobalt ferrite nanometer magnetic material with high magnetic permeability and low loss is mainly prepared from the following components: ferric chloride, cobalt chloride hexahydrate, manganese chloride, zinc sulfate, modified propylene glycol alginate acid ester, lithium chloride, silicon nitride and barium carbonate. The cobalt ferrite nanometer magnetic material prepared by the application has the characteristics of high magnetic permeability and low loss.

Provided are cobalt ferrite particles having a micrometer-order average particle diameter and similar particle diameters. When a cobalt ferrite precursor is treated at a high temperature and a high pressure, an oxidation reaction is caused in the presence of a complexing agent, thereby obtaining intended cobalt ferrite magnetic particles.

The invention discloses cobalt ferrite, a high-permeability iron-silicon magnetic powder core and a preparation method and application of the high-permeability iron-silicon magnetic powder core, and relates to the field of magnetic materials. The preparation method comprises the following steps: mixing and coating cobalt ferrite nanoparticles and phosphorylated magnetic powder, mixing and coating with an insulating coating agent, mixing and coating with a release agent, and carrying out compression molding and heat treatment to obtain the high-permeability iron-silicon magnetic powder core. According to the FeSi-cobalt ferrite magnetic powder core and the preparation method thereof, the FeSi soft magnetic alloy powder is subjected to insulation coating by adopting cobalt ferrite magnetism with high magnetic induction intensity, gaps among the magnetic powder can be effectively filled, the content of a magnetic medium is increased, the magnetic dilution effect is reduced, and the FeSi-cobalt ferrite magnetic powder core has high magnetic conductivity, low loss and excellent comprehensive electromagnetic performance.

The invention provides a method and system for removing high-concentration complex cyanogen in gold extraction wastewater, and relates to the technical field of sewage treatment.The method comprises the steps that the pH of the gold extraction wastewater is adjusted to 8-10, and pretreated wastewater is obtained; adding a cobalt ferrite particle catalyst into the pretreated wastewater, and introducing ozone to obtain oxidized effluent; dividing the oxidized effluent into a solution A and a solution B according to a volume ratio, oxidizing the solution A by using anaerobic ammonium oxidation bacteria under the condition of low dissolved oxygen, and mixing the oxidized solution A with the untreated solution B to obtain a mixed solution; enabling the mixed solution to react with anaerobic ammonium oxidation bacteria through a porous adsorption material, and recovering the cobalt ferrite particle catalyst for recycling. According to the method, the removal rate of the high-concentration complex cyanogen can be effectively increased, thorough mineralization of the complex cyanogen is achieved, and the core problem that the complex cyanogen is difficult to degrade is solved; and the method and the system have relatively high load resistance, are simple and convenient to operate and have good adaptability.

The invention discloses trace cobalt-doped magnetic nanoparticles as well as a preparation method and application thereof, and relates to the technical field of magnetic nano materials. According to the method, the magnetic nanoparticles are cobalt ferrite, the chemical formula of the cobalt ferrite is CoxFe3-xO4, and 0 lt; x < = 0.1; cobalt ions in the cobalt ferrite are doped in octahedral sites on the surface of the crystal lattice. And synchronous regulation and control of dynamic magnetization characteristics are realized by selectively doping cobalt ions to specific sites in crystal lattices. By accurately controlling the doping amount of cobalt, the magnetization intensity (Ms) of the magnetic nanoparticles is remarkably improved, and the relaxation time (tau) is adjusted, so that the MPI signal and MHT curative effect are remarkably improved.

Provided are: a method for producing composite particles in which seed particles and cobalt ferrite particles can be synthesized with relatively low energy, the composite particles having a particle diameter within a specific range, having a circular shape with a predetermined average circularity, and having specific magnetic characteristics; composite particles of seed particles and cobalt ferrite particles manufactured by this manufacturing method have a circular shape having a predetermined average circularity, have specific magnetic properties, and have uniform particle diameters. The provided method for manufacturing composite particles of seed particles and cobalt ferrite particles comprises: a step in which a ferrous salt and a cobalt salt are stabilized by a complexing agent in an aqueous solution to prepare a ferrite precursor; a step in which spherical or substantially spherical seed particles are added to the ferrite precursor; and a step in which the ferrite precursor is additionally heat-treated.

This invention provides cobalt ferrite, its preparation method, and its application, belonging to the field of water treatment technology. The preparation method provided by this invention includes the following steps: (1) mixing cobalt salt, iron salt, and water to obtain a mixed solution; (2) mixing the mixed solution obtained in step (1) with an alkaline solution and carrying out a hydrothermal reaction to obtain cobalt ferrite; the temperature of the hydrothermal reaction is 155–165°C. This invention uses cobalt salt and iron salt as raw materials to prepare cobalt ferrite through a hydrothermal reaction. By controlling the temperature of the hydrothermal reaction, the obtained cobalt ferrite also contains iron(III) oxide (Fe3O4). The interaction between the two results in a faster removal rate of the prepared cobalt ferrite when used for pollutant removal in water, allowing for pollutant degradation in a shorter time. The results of the examples show that when the cobalt ferrite prepared by this invention is used to remove bisphenol A from water, its removal rate reaches nearly 100% within 5 minutes.

The invention discloses a preparation method of carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder, which comprises the following specific steps: weighing ferrite synthetic components, spherical carbonyl iron powder and tetraethoxysilane according to a ratio, the ferrite synthetic components comprise 52-56 mol% of Fe2O3 and the balance of CoO, and the spherical carbonyl iron powder and the tetraethoxysilane are mixed according to a certain ratio to prepare the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder, and the spherical carbonyl iron powder and the tetraethoxysilane are mixed according to a certain ratio to prepare the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder. The carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is finally obtained through the steps of ball milling, stirring, drying, primary sintering, mixing, secondary sintering and the like. The method for preparing the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is simple and convenient in process, safe and low in cost, and after the carbonyl iron powder, cobalt ferrite and silicon dioxide wave-absorbing powder is used for preparing wave-absorbing products, the excellent performance of broadband strong absorption is shown in the frequency band of 2-18 GHz.

The invention discloses a multifunctional electro-catalytic material based on a cobalt ferrite nano array and a preparation method of the multifunctional electro-catalytic material in the field of electro-catalytic materials. The multifunctional electro-catalytic material is prepared from the following raw materials: a CoFe2O4 nano array substrate, ZIF-67 derived Co-N-C nano cubes and nitrogen-doped carbon nanofiber loaded Fe monatomic. The CoFe2O4 nano array substrate grows on the carbon cloth substrate through a hydrothermal method; the ZIF-67 derived Co-N-C nanocube is prepared by the following steps: stirring Co (NO3) 2.6 H2O and 2-methylimidazole in methanol, dipping a substrate, standing, drying, and calcining at 800-810 DEG C in an Ar atmosphere, thereby obtaining the ZIF-67 derived Co-N-C nanocube. According to the material, the activity and stability of OER, ORR and HER are improved through the synergistic effect of the two modified components, and the material is suitable for the field of clean energy conversion.

To provide magnetic particles (cobalt ferrite) having an average particle size of μm order and uniform particle size.SOLUTION: Cobalt ferrite magnetic particles are obtained by heat-treating a cobalt ferrite precursor in the presence of sulfite.SELECTED DRAWING: Figure 1

A transmission line is disclosed which includes a first conductor, a second conductor, a composite disposed between the first conductor and the second conductor, the composite includes non-linear inclusions comprising one or more of non-linear dielectric and non-linear magnetic inclusions mixed in a matrix material, wherein the non-linear dielectric inclusions are selected from the group consisting of barium strontium titanate (BST), barium titanate, strontium titanate, barium zirconate titanate, lead zirconate titanate, lead titanate, lithium niobate, potassium niobate, lead scandium tantalate, strontium barium niobate, and combinations thereof, and the non-linear magnetic inclusions are selected from the group consisting of nickel zinc ferrite (NZF), manganese zinc ferrite, cobalt ferrite, manganese ferrite, zinc ferrite, nickel ferrite, and combinations thereof, wherein the non-linear inclusions by volume are about 25% NZF, about 10% BST / 15% NZF, and about 15% BST / 10% NZF, and wherein the first conductor, the second conductor, and the composite form a capacitor.

The invention belongs to the field of magnetostrictive materials, and mainly relates to a preparation method for improving the magnetic performance of a cobalt ferrite material. The process mainly comprises the following steps: preparing raw material powder, ball-milling and mixing the powder, pre-sintering, performing secondary ball-milling, adding lubricating powder and doping magnetically soft alloy iron cobalt vanadium, performing third-time ball-milling and compression molding, removing plastic from a green body and orienting, sintering, and performing magnetic field annealing. The cobalt ferrite is prepared by doping a certain proportion of soft magnetic alloy iron, cobalt and vanadium and carrying out magnetic field orientation on the soft magnetic alloy iron, cobalt and vanadium, the magnetic conductivity of the cobalt ferrite can be effectively improved, the density of the obtained magnetostrictive material cobalt ferrite is greater than 95%, and the magnetostrictive excitation magnetic field is less than 1100Oe. The magnetostrictive performance of the cobalt ferrite can be effectively improved, and the cobalt ferrite can be better applied to the fields of ultrasonic precision machining, magnetostrictive ultrasonic transducers and the like.

The invention relates to the technical field of analysis and detection, in particular to a molecular imprinting sensor for detecting linoleic acid as well as a preparation method and application of the molecular imprinting sensor. The preparation method of the molecularly imprinted sensor comprises the following steps: firstly, preparing a palladium nanoparticle-graphene oxide / cobalt ferrite composite material solution, then taking 4-vinylpyridine as a functional monomer, taking linoleic acid as a template molecule, carrying out copolymerization with the composite material under the action of a cross-linking agent and an initiator, and eluting the template molecule to prepare a molecularly imprinted polymeric material; and coating the coating on an electrode. The molecular imprinting sensor disclosed by the invention can be used for rapidly and accurately detecting the content of LA in samples such as pork and the like, and high-sensitivity and high-selectivity detection of linoleic acid is realized. The molecular imprinting sensor is simple in preparation method and low in manufacturing cost, and has a wide application prospect in the field of food safety detection.

The application provides a method and system for removing high-concentration complex cyanide in gold extraction wastewater, and relates to the technical field of sewage treatment. The method comprises the following steps: adjusting the pH of the gold extraction wastewater to 8-10 to obtain pretreated wastewater; adding a cobalt ferrite particle catalyst to the pretreated wastewater and introducing ozone to obtain oxidized effluent; dividing the oxidized effluent into solution A and solution B according to the volume ratio, oxidizing solution A under the condition of low dissolved oxygen by using anaerobic ammonia oxidation bacteria, mixing the oxidized solution A with untreated solution B to obtain a mixed solution; and reacting the mixed solution with porous adsorption material and anaerobic ammonia oxidation bacteria, and recycling the cobalt ferrite particle catalyst for circulation. The method used by the application can effectively improve the removal rate of high-concentration complex cyanide, realizes complete mineralization of the complex cyanide, solves the core problem of difficult degradation of the complex cyanide, has strong load resistance, is simple to operate, and has good adaptability.

The invention belongs to the field of biomedical materials, and discloses a magnetoelectric hydrogel microneedle, the magnetoelectric hydrogel microneedle comprises a backing and a microneedle array, the backing comprises hydrogel containing magnetic ionic liquid Fe-IL and thiolated chitosan, and the microneedle array comprises magnetoelectric nanoparticles and hydrogel; the magnetoelectric nano-particles are CB core-shell structure nano-particles of which the surface of magnetic nano cobalt ferrite (CFO) is coated with a piezoelectric responsive barium titanate (BTO) shell layer. The invention further discloses a preparation method of the magnetoelectric hydrogel microneedle and application of the magnetoelectric hydrogel microneedle in preparation of products for treating bone tissue repair. During preparation, CB gradient distribution is regulated and controlled through an external magnetic field, the magnetoelectric response efficiency is enhanced, when the magnetoelectric hydrogel is applied to preparation of products for treating bone tissue repair, the osteogenesis efficiency can be improved, the adaptability of the magnetoelectric hydrogel to the bone tissue can be enhanced, and efficient electrical stimulation repair of the bone tissue is achieved.

The invention provides cobalt ferrite as well as a preparation method and application thereof, and belongs to the technical field of water treatment. The preparation method provided by the invention comprises the following steps: (1) mixing cobalt salt, ferric salt and water to obtain a mixed solution; (2) mixing the mixed solution obtained in the step (1) with alkali liquor, and carrying out hydrothermal reaction to obtain cobalt ferrite; the temperature of the hydrothermal reaction is 155 to 165 DEG C. The cobalt salt and the iron salt are used as raw materials, the cobalt ferrite is prepared through the hydrothermal reaction, the temperature of the hydrothermal reaction is controlled, the obtained cobalt ferrite further contains ferroferric oxide, and the cobalt ferrite and the ferroferric oxide interact with each other, so that the prepared cobalt ferrite has a higher removal rate when being used for removing pollutants in a water body, and degradation of the pollutants can be completed within a shorter time. The result of the embodiment shows that when the prepared cobalt ferrite is used for removing bisphenol A in a water body, the removal rate of the cobalt ferrite reaches nearly 100% within 5 minutes.

The invention discloses an MXene / PEDOT: PSS / CNT (at) CoFe2O4 electromagnetic shielding film and a preparation method thereof. A bottom layer of the film is MXene, a transition layer is MXene / PEDOT: PSS, an absorption mixing layer is an MXene / PEDOT: PSS / CNT (at) CoFe2O4 layer, and the bottom layer, the transition layer and an upper layer are sequentially subjected to suction filtration; the preparation method comprises the following steps: forming a gradient structure from high conductivity to high impedance by regulating and controlling the mass fractions of PEDOT: PSS and magnetic powder CNT coated CoFe2O4 in different layers, and promoting multiple reflection and loss of electromagnetic waves in the film by combining a magnetoelectric synergistic effect and matching interface impedance; magnetic particles of cobalt ferrite CoFe2O4 are loaded on carboxylated carbon nanotubes MWCNT-COOH by adopting a coprecipitation method, so that the absorption performance of the film is enhanced. The film is prepared through layer-by-layer vacuum filtration and hot pressing, and has high electromagnetic shielding effectiveness, strong absorption characteristic, flexibility and mechanical strength.

The present application discloses an electromagnetic rheological copper-aluminum rolling oil and its preparation method and application, which relate to the field of lubricant technology. The electromagnetic rheological copper-aluminum rolling oil comprises titanium dioxide-coated cobalt ferrite, base oil and additives. First, the titanium dioxide-coated cobalt ferrite is prepared, and then added to the base oil, and then a surfactant, an extreme pressure agent and an antioxidant are added to the base oil, and the electromagnetic rheological copper-aluminum rolling oil is prepared after mixing and stirring. The electromagnetic rheological copper-aluminum rolling oil has both good electrorheological properties and magnetorheological properties, and has good suspension stability; it can also adjust its oil film thickness, viscosity and shear stress by changing the parameters of the electromagnetic field, thereby reducing the slippage and scratching problems during the rolling process and achieving the effect of intelligent cleaning; the electromagnetic rheological copper-aluminum rolling oil can be used for the rolling of copper, aluminum and their alloys.