82 results about "Multiwalled carbon" patented technology

The application relates to the technical field of composite materials, and particularly discloses a carbon fiber / epoxy electromagnetic shielding composite material with strong interface bonding and a preparation method thereof, which comprises the following steps: hydrothermal reaction of oxidized carbon fibers O-CF, an organic ligand and an iron source in a solvent, washing and drying of the fibers to obtain MIL-loaded carbon fibers, carbonization treatment to obtain iron-based oxide-loaded carbon fibers dF@CF, vacuum-assisted introduction of epoxy resin into the multilayer carbon fibers dF@CF, and curing to obtain the carbon fiber / epoxy electromagnetic shielding composite material. The organic ligand and trivalent iron ions are used to synthesize a large number of rhombic MILs on the active sites on the surface of the carbon fibers, the MILs are reduced into iron-based oxide nanoparticles after carbonization, the iron-based oxide nanoparticles are closely loaded on the surface of the carbon fibers, the interface bonding performance is improved, the electromagnetic shielding efficiency is increased, and the carbon fiber / epoxy composite material with both the interface and the electromagnetic shielding efficiency is realized.

The invention relates to the technical field of coatings, and discloses a polysilazane-graphene composite electrical equipment insulating and pressure-resistant protective coating and a preparation method thereof. The flame-retardant coating is prepared from the following raw materials in parts by mass: 30 to 50 parts of polysilazane, 3 to 5 parts of telomer, 1 to 3 parts of synergist, 4 to 5 parts of modified silicon dioxide, 4 to 5 parts of modified graphene, 1.5 to 2 parts of multiwalled carbon nanotube, 0.5 to 2 parts of modified zinc oxide, 1 to 2 parts of fluorocarbon surfactant and 130 to 230 parts of tetrahydrofuran. By introducing the telomer, the adhesive force of the coating on a rusty surface is effectively improved, and the properties of high temperature resistance, insulation and pressure resistance, flame retardance, water resistance, ice condensation resistance and the like are enhanced; by introducing the synergist, the modified silicon dioxide, the modified graphene, the multi-walled carbon nanotubes and the modified zinc oxide, the protection capability is further improved. Therefore, the coating disclosed by the invention is excellent in comprehensive protection performance, can meet the long-term operation requirement of power equipment in a complex and severe environment, and is wide in application prospect.

The invention discloses a high-performance silicon-carbon negative electrode material and a preparation method thereof, and relates to the technical field of lithium ion battery materials, the high-performance silicon-carbon negative electrode material comprises a porous carbon material, the surface of the porous carbon material is successively deposited with a carbon nanotube network and nano silicon, the porous carbon material on which the carbon nanotube network and the nano silicon are deposited is also provided with a secondary outer layer carbon shell and an outer layer carbon shell from inside to outside; according to the invention, double optimization of the silicon-carbon negative electrode material is realized through a unique structural design: (1) the volume expansion effect of nano silicon is relieved through cooperation of the carbon nanotube network and the multi-layer carbon shell; and (2) the migration rate of lithium ions is accelerated by the carbon nanotubes and the multi-layer carbon coated structure, and the prepared silicon-carbon negative electrode material has excellent cycling stability and rate capability.

The invention discloses a low-noise and low-rolling-resistance tire tread and a preparation method thereof, and relates to the technical field of tire production, the low-noise and low-rolling-resistance tire tread comprises a supporting layer and multiphase composite tread rubber; the multiphase composite tread rubber comprises a continuous phase matrix, white carbon black with a two-phase structure, functionalized multiwalled carbon nanotubes, a disilane coupling agent, dynamic crosslinking thermoplastic elastomer particles, zinc oxide, stearic acid, an anti-aging agent, an accelerant and sulfur, and good wear resistance and mechanical strength are kept while the rolling resistance and driving noise of a tire are remarkably reduced.

The invention relates to the technical field of rail transit equipment, and particularly discloses a multifunctional inward-bending bow beam for rail transit equipment, which comprises a beam body, connecting end blocks are arranged at the left end and the right end of the beam body, the beam body and the connecting end blocks are integrally formed and are in an inward-bending shape, and the beam body and the connecting end blocks are formed by compounding a plurality of layers of carbon fiber prepregs. A plurality of second penetrating holes are formed in the upper end direction and the lower end direction of the middle portion of the beam body, rectangular holes are formed in the left end direction and the right end direction of the two connecting end blocks, bolt holes are formed in the front ends of the connecting end blocks and communicate with the rectangular holes, a module mounting component is arranged at the middle end of the beam body, and fixing components are arranged at the outer ends of the two connecting end blocks. The module mounting component comprises a connecting sleeve which is in a U shape, and the module mounting component is suitable for a vehicle body structure supporting component of rail transit equipment such as a high-speed train, a light rail and a subway, and has the functions of light weight, high strength, fatigue resistance and dynamic deformation monitoring.

This application discloses an impact buffer structure, which includes an inner support, a buffer layer, and a paint layer. The buffer layer is disposed on the outer surface of the inner support, and the paint layer is disposed on the outer surface of the buffer layer. The buffer layer contains a mesh and multiple layers of carbon fiber balls. This application can improve the buffering capacity of the impact buffer structure and increase its service life.

A device (1) for rapidly transferring thermal energy from a thermal energy source (A) to a destination point (B) at a rate higher than the convection and heat transfer capacity of adjacent means 2 and for capturing said thermal energy point or surface, wherein a thermoelectric conversion means located at the destination point B can convert the thermal energy into electrical energy with zero emissions harmful to the environment and living things. The thermal energy is transferred by a coating 4 composed of a plurality of nanometric layers with atoms forming a regular geometric structure (Figure 1). The present invention also relates to a device for the transfer of thermal energy having multiple layers of carbonaceous material on a planar or non-planar (three-dimensional shape), opaque, transparent or translucent, rigid or semi-rigid substrate of fabric, metallic or non-metallic or flexible material, having flexible but not opaque, transparent or translucent natural or synthetic fibers. The present invention also includes a method for manufacturing a device (10 or 10a) for the rapid transfer of thermal energy. The method comprises at least one deposition step of at least one layer (12, 12a-12b-12c-12d, etc.) of a carbonaceous material having a regular geometric structure on a support substrate (11 or 11a) in an environment (110) of a deposition machine (100), the environment being vacuum-packed under controlled temperature and pressure conditions and isolated from the external environment, the deposition being performed along a direction perpendicular or locally radial to a plane or shape substantially defined by the support substrate (11 or 11a). The present invention also relates to an integrated system for generating electrical energy using said device coupled to a possible generator other than a renewable energy source of thermoelectric generator, photovoltaic and / or thermoelectric-photovoltaic and / or motive power type, all used jointly for the supply of an electrical load.

The invention particularly relates to a polytetrafluoroethylene sealing element material and a manufacturing method thereof. The polytetrafluoroethylene sealing element material comprises the following raw materials in parts by weight: 70-99 parts of modified polytetrafluoroethylene resin, 5-15 parts of glass fibers, 3-10 parts of carbon fibers, 2-10 parts of bronze powder, 0.5-1 part of furan ring-containing thermosetting resin microcapsules, 0.5-2 parts of multiwalled carbon nanotubes, 0-5 parts of a lubricant and 0-3 parts of a functional aid. According to the polytetrafluoroethylene sealing element material disclosed by the invention, the mechanical property, wear resistance and sealing property of a sealing element are remarkably improved by optimizing the types and contents of the filling agent, the lubricating agent and the functional additive, and the sealing element disclosed by the invention is suitable for sealing application in high-temperature, high-pressure and strong-corrosion environments and has a wide market prospect.

The present invention discloses a method for preparing a highly dispersed five-element high-entropy alloy-loaded carbon sponge absorber. First, a high-energy metal hydride (MOF) rich in zinc-based triazole is synthesized as a precursor. A layered porous carbon sponge is then obtained under inert gas and high-temperature heat treatment conditions. Five metal salts are selected and simultaneously reduced with a saturated sodium borohydride aqueous solution and a hydrogen-argon mixture to obtain a high-entropy alloy loaded on a multilayer carbon network structure. This absorber achieves a reflection loss of 35 dB at 2.7 mm and an effective absorption bandwidth of 9.44 to 13.56 GHz, covering the entire X-band.

The present disclosure belongs to the technical field of lithium battery cathode materials, and discloses a preparation method of multiple carbon-coated high-compaction lithium iron manganese phosphate, comprising the following steps: (1) synthesizing a carbon and vanadium co-doped ferromanganese phosphate precursor through a co-precipitation method, sintering, and removing crystal water to obtain an anhydrous ferromanganese phosphate precursor; (2) adding lithium phosphate, a supplemental phosphorus source, an organic carbon source, a dopant and deionized water, and performing ball milling, wet sanding, spray drying and sintering to obtain an intermediate material; and (3) adding deionized water and the organic carbon source, then performing ball milling, sanding, spray drying, sintering and air jet pulverization to obtain multiple carbon-coated high-compaction lithium iron manganese phosphate.

The invention relates to a polypropylene composition as well as a preparation method and application thereof. The polypropylene composition comprises the following components in parts by weight: 58-86 parts of polypropylene, 5-17 parts of conductive carbon black, 3-9 parts of multiwalled carbon nanotubes and 0.5-2 parts of an antioxidant. The surface of the multi-walled carbon nanotube is modified with carboxyl; the mass ratio of the conductive carbon black to the multi-walled carbon nanotubes is (1.5-3): 1. According to the invention, the polypropylene is used as a resin matrix and added into the multi-walled carbon nanotube with the surface modified with carboxyl, and the mass ratio of the conductive carbon black to the multi-walled carbon nanotube is controlled within a specific range, so that the prepared polypropylene composition not only has high electromagnetic shielding effectiveness, but also has high tensile strength retention rate after thermal aging treatment, and the electromagnetic shielding performance of the polypropylene composition is improved. And the thin-wall injection molding requirement can be met.

The utility model discloses a shock-resistant cable protection pipe connector, which relates to the technical field of protection pipe connectors and comprises a connector, two groups of fixing sheets are fixedly connected to the front end and the rear end of the top of the connector, and a shock-resistant component is fixedly connected to the periphery of the connector. According to the shock-resistant cable protection pipe connector, by arranging the Y-shaped reinforcing ribs, the multiple layers of carbon fiber honeycomb pieces and the carbon fiber arched plates, when the shock-resistant cable protection pipe connector is used, firstly, the interior is protected through the steel shell, internal and external deformation caused by impact force is prevented, meanwhile, after the impact force is inwards transmitted into the pressure bearing layer, external pressure and impact are effectively resisted through the Y-shaped reinforcing ribs, and the service life of the cable protection pipe connector is prolonged. Stress is dispersed, after the carbon fiber arched plates in the supporting layers bear pressure, the pressure is downwards and outwards transmitted to the adjacent multi-layer carbon fiber honeycomb pieces and finally enters the retarding layers, the springs buffer and weaken the pressure, finally, the pressure is transmitted to the high-density sponge, additional impact resistance is provided, and the problem that the impact resistance of the device is poor is solved.

An improved method of maturation of an unaged or partially aged distilled spirit, the method comprising: exposing the spirit to at least one catalytic material consisting of a group selected from: iron oxide nanoparticles, alumina-supported Fe(II) complexes, Pd / C, multiwalled carbon nanotubes, carbon xerogels, carbon based solid acid catalysts, SO42- / TiO2 / γ-Al2O3, an element selected from the group consisting of: columns 4-12 transition metals except for Fe, column 13 boron group, Si, and mixtures thereof; wherein throughout the exposing, the spirit is not being distilled, and the exposing is allowed until level of at least one maturation congener in the spirit attains predetermined desired congener level / s in the spirit.

The application relates to a structural health monitoring system and application thereof. A preparation method of a carbon fiber reinforced thermoplastic composite material involved in the system comprises the following steps: providing a plurality of carbon fiber reinforced thermoplastic resin layers; prepositioning a multifunctional sensor unit array between adjacent thermoplastic resin layers, the multifunctional sensor unit array comprising a functional film containing ferroelectric ceramic, an electrode layer, and an insulating protective layer between the functional film and the carbon fiber layer; wherein the functional film comprises ferroelectric ceramic material with dielectric and piezoelectric response characteristics; and performing selective laser solidification on the layer area prepositioned with the multifunctional sensor unit array, so that the layer interface locally melts under the action of laser heating and embeds the multifunctional sensor unit array between adjacent layers; wherein the peak temperature of the laser heating area in the selective laser solidification process is not higher than 200 DEG C.

The utility model discloses an efficient gluing device for carbon fiber prepreg cloth, which belongs to the technical field of carbon fiber prepreg cloth, and adopts the technical scheme that the efficient gluing device comprises a dipping gluing box, a supporting plate is arranged at the top of the dipping gluing box, and clamping mechanisms are arranged on the two sides of the rear side of the top of the dipping gluing box; fixing mechanisms are arranged on the two sides of the rear side of the top of the dipping and gluing box; the clamping mechanism comprises two sliding rods, a plurality of clamping plates, two sliding blocks, a plurality of connecting belts and two springs, the sliding blocks are connected to the surfaces of the sliding rods in a sliding mode, the bottoms of the sliding blocks are fixedly connected with the top of the top clamping plate, the connecting belts are fixedly connected between the rear sides of the adjacent clamping plates, the surfaces of the sliding rods are movably sleeved with the springs, and the springs are fixedly connected with the top of the top clamping plate. The problem that the gluing efficiency of the carbon fiber prepreg cloth is low due to the fact that an existing part of structures for gluing the carbon fiber prepreg cloth are inconvenient to glue multiple layers of carbon fiber prepreg cloth at the same time is solved.

Disclosed is a hybrid composite anode for a lithium ion battery comprising silicon nanoparticles, a multiwalled carbon nanotube (MWCNT) sheet, and a polymeric binder capable of enhancing capacity retention of the hybrid composite anode. Also disclosed is a method of manufacturing an anode for a lithium ion battery, the method comprising the steps of: manufacturing a carbon nanotube (CNT) pad on an anode current collector; dispersing the manufactured CNT pads in a mixture of deionized (DI) water and ethanol using a probe-type ultrasonic generator and a magnetic stirrer; and adding silicon nanoparticles, a multi-walled carbon nanotube (MWCNT) sheet, and a polymeric binder to the mixture, thereby forming a Si-MWCNT nanocomposite (SMC) anode.

The present invention relates to the technical field of functional composite materials, and provides an ultra-light wide-angle wave-absorbing metamaterial based on 2-18 GHz full-frequency absorption of low-price and easily-available carbon-based conductive films and easy to manufacture, and a manufacturing method therefor. The metamaterial comprises a first dielectric substrate, a first carbon-based conductive thin film structure array layer, a second dielectric substrate, a second carbon-based conductive thin film structure array layer, a third dielectric substrate, and a third carbon-based conductive thin film structure array layer which are sequentially stacked from bottom to top. The first, second and third carbon-based conductive thin film structure array layers are all formed by periodically arranging discrete carbon-based conductive thin film patches. According to the present invention, by means of coupling of multilayer carbon-based conductive thin film periodic unit arrays, a wave-absorbing metamaterial having the characteristics of low price, easy formation processing, ultra-lightness, ultra-wideband, stable large incident angle, high absorptivity, and the like is obtained; the metamaterial weighs 0.4-0.5 kg per square meter, which is only 1 / 100 of that of a traditional absorber of the same size. The metamaterial has an absorption rate of 90% or more in a full frequency range of 2-18 GHz.

The invention discloses a reinforcing and toughening ice material composite foundation for polar region engineering, and particularly relates to the technical field of foundations, the reinforcing and toughening ice material composite foundation comprises a first foundation base, a second foundation base is arranged at the top of the first foundation base, and a supporting assembly is arranged between the first foundation base and the second foundation base; the supporting assembly comprises a first base plate arranged in the middle of the second foundation base, a second base plate is arranged in the middle of the first foundation base, and the first base plate and the second base plate are arranged in a stacked mode. The first base plate and the second base plate are formed by stacking the multiple layers of carbon fiber reinforced ice composite plates, and after basalt fibers and nano zirconium oxide are doped for reinforcement, the defects that pure ice is low in strength and poor in toughness are effectively overcome, so that the second foundation base achieves height fine adjustment within a certain range relative to the first foundation base; height change and ice surface settlement caused by ice layer freezing and thawing can be adapted in real time, it is ensured that the upper structure is always in a horizontal stable state, and the problem that a traditional foundation cannot be dynamically adapted to polar region ice surface deformation is solved.

A nanocomposite proximity-pressure sensor (NPPS), configured to measure one or more human biometrics, the NPPS including a carbon nanotube-paper (CPC) electrode, a multiwalled carbon nanotubes (MWCNTs) foam, and an auxetic MWCNTs-embedded frame, wherein the auxetic MWCNTs-embedded frame is positioned around the MWCNTs foam, wherein when the auxetic frame is compressed, it expands and exerts a pressure onto the MWCNTs foam.

The invention discloses a piezoelectric interface modified piezoelectric ion sensor and a preparation method and application thereof, and belongs to the field of flexible piezoelectric ion sensors, multiwalled carbon nanotubes are dispersed in NMP to form a suspension, and vacuum filtration and drying are performed to obtain a multiwalled carbon nanotube film; the BPNA powder is dissolved in a DMF / ethanol solution, and BPNA crystals are obtained through a liquid-liquid diffusion method; dissolving PEO in deionized water to obtain a PEO solution; adding the BPNA crystal into the PEO solution to obtain a PEO / BPNA dispersion liquid; adding ionic liquid into the PEO solution to obtain PEO / IL dispersion liquid; pouring the PEO / BPNA dispersion liquid on a glass plate to obtain a PEO / BPNA layer; a PEO / IL dispersion liquid is poured on the PEO / IL layer to form a PEO / IL middle layer; and pouring a PEO / BPNA layer on the multi-walled carbon nanotube electrode film layer to obtain an electrolyte, and laminating two multi-walled carbon nanotube electrode film layers on two sides of the electrolyte to obtain the assembled sensor.

The invention discloses a stretchable elastic carbon nanofiber membrane material and a preparation method thereof. The preparation method comprises the following steps: respectively dissolving polystyrene and a carbon precursor polymer to prepare a spinning solution, spinning according to a certain combination sequence to obtain a multi-layer carbon precursor nanofiber membrane, and inducing the construction of a micro-buckling structure of the carbon precursor nanofiber membrane by utilizing a thermal shrinkage effect of a polystyrene layer to obtain the multi-layer carbon precursor nanofiber membrane. Polystyrene is dissolved and removed through ethyl acetate, a nanofiber membrane only retaining a pure carbon precursor is obtained, and finally the stretchable elastic carbon nanofiber membrane is obtained through pre-oxidation and carbonization. The elastic carbon nanofiber membrane prepared by the invention has excellent tensile resilience, high conductivity and high specific surface area, and can be applied to the application fields of national defense and military industry, energy environmental protection, aerospace, flexible electronics and the like.

The application discloses a kind of resistance stable stretchable conductive fiber and its continuous preparation method, comprising the following steps: S1, with elastic fiber as baseline, through feeding roller pay-off, after wetting, coating carbon nanotube, solvent bath, drying, through collection roller take-up;The linear velocity of collection roller is greater than the linear velocity of feeding roller;S2, the fiber obtained in the previous step is payed-off by feeding roller, after wetting, coating carbon nanotube, solvent bath, drying, through collection roller take-up;The linear velocity of feeding roller and collection roller is the same as step S1;S3, repeat step S2 to coat multiple layers of carbon nanotube, and obtain resistance stable stretchable conductive carbon fiber.The application uses elastic fiber as baseline, realizes the elongation of elastic fiber to preset multiple by the speed difference of feeding roller and collection roller, and obtains resistance stable stretchable conductive fiber by wetting and coating carbon nanotube multiple times, and the preparation method is simple, low in cost, and continuous production can be realized.

An electrode and a supercapacitor comprising such an electrode are disclosed. The electrode may include a multilayered structure comprising at least one layer made from a mixture of two different types of carbon particles and a binder. At least one of the carbon types is an activated carbon, meaning a carbon having a surface area of between 2000 to 4000 [m2 / g], and the other type of carbon is nanostructured carbon having at least one dimension lower than 100 nm and an average surface area of between 200 to 2500 [m2 / g]. Such an electrode, when assembled in a supercapacitor increases the energy storage capacity of the supercapacitor.

The application discloses a method for preparing gradient multistage multilayer carbon film on the surface of fluoroether rubber by Cr / Ti co-doping, wherein the substrate is washed, dried, and then placed into a magnetron sputtering cavity; Ar gas is introduced to clean the substrate under high vacuum condition; and then modified metal micro-doped carbon film is obtained by adopting cathode arc magnetic filtering technology. The obtained co-doped carbon film obviously improves the friction performance, the hydrogenated amorphous carbon film composition in the film is increased, and meanwhile, the film itself density and hardness are maintained; the cathode arc magnetic filtering technology makes the doping elements uniformly disperse in the film, so that the film performance is improved by a small amount of doping elements; the order degree of the friction interface of the film is obviously improved during the friction process, the film has low friction coefficient and low wear rate, and the tribological performance of the film is improved.

This invention belongs to the field of transmission device technology and discloses a perfectly coupled secure information transmission device based on a multilayer nanofilm structure filled with a dielectric sheet. The device includes an input region, a transmission region, and an output region; the input and output regions are free space; the transmission region consists of a three-layer "sandwich" structure, which is formed by two layers of non-magnetic ENZ dielectric wrapped around a thin dielectric plate. This invention analyzes the effect of the amount of dielectric dopant on the electromagnetic resonant bandwidth of the doped ENZ dielectric when the above structure is equivalent to a lossy EMNZ material. The analysis shows that with the increase of the amount of dopant, the resonant bandwidth of the entire structure is significantly broadened, thereby extending the perfect absorption bandwidth of the above structure. Simultaneously, by using a multilayer Ag / silicon carbide nanofilm structure filled with dopant at a wavelength of 430 nm, an optically perfect absorber based on a lossy EMNZ dielectric with an extended operating bandwidth is designed.

A method for producing an electrically conductive conductor bundle (1) comprising at least one carbon conductor (3), comprising the following steps: a) producing or providing the conductor bundle (1) as an intermediate product comprising at least one carbon conductor (3), the carbon conductor in particular comprising graphite, pyrolytic graphite, graphene, graphyne and / or carbon nanotubes, b) introducing the conductor bundle (1) and one or more intercalation substances (2), in particular one or more metal halides or one or more organic alkali metals, into the gaseous or liquid phase of a reactor volume (5), wherein the intercalation substances are suitable for intercalation into the material of the at least one carbon conductor (3) of the conductor bundle (1), and c) subjecting the conductor bundle (1) to a thermal treatment, wherein the reactor volume (5) is brought to a process temperature in order to induce intercalation (4), wherein atoms or molecules of the intercalation substance (2) are intercalated into the material of the respective carbon conductor (3), in particular accumulated on the carbon structure of the carbon conductor (3), in particular in the regions between the layers of the multilayer carbon structure.

The invention provides a cut-resistant and stab-resistant fabric and a preparation method thereof. The cut-resistant and stab-resistant fabric comprises an outer layer, an interface enhancement layer, a middle layer and an inner layer which are sequentially arranged from outside to inside, the middle layer is prepared from the following raw materials in parts by weight: 20 to 30 parts of EVA (Ethylene-Vinyl Acetate), 15 to 25 parts of TPU (Thermoplastic Polyurethane), 8 to 15 parts of EPDM (Ethylene-Propylene-Diene Monomer), 5 to 12 parts of TPO (Thermoplastic Polyolefin), 6 to 12 parts of ceramic microbeads, 1 to 4 parts of multiwalled carbon nanotubes, 0.3 to 0.8 part of antioxidant, 0.2 to 0.6 part of ultraviolet light absorber and 7 to 14 parts of nano silicon nitride-ethylene propylene diene monomer composite reinforcement. Oxidation and aging of the material can be effectively delayed, and the service life of the middle layer and even the whole fabric is prolonged.

The invention relates to the technical field of chemical material preparation, in particular to a multi-walled carbon nanotube and rubber composite material and a preparation method thereof, and the preparation method comprises the following steps: preparing a multi-walled carbon nanotube aqueous solution; carrying out ultrasonic treatment on the aqueous solution for 5 minutes to obtain a multiwalled carbon nanotube aqueous solution; the preparation method comprises the following steps: immersing an auxiliary agent into a multiwalled carbon nanotube aqueous solution, magnetically stirring at 45 DEG C for 30 minutes, and finally carrying out ultrasonic treatment on the mixed solution for 5 minutes; adding natural rubber into the multi-walled carbon nanotube mixed solution for mixing, and uniformly stirring the mixed solution to obtain a multi-walled carbon nanotube and natural rubber mixed solution; pouring a mixed solution of the multi-walled carbon nanotubes and the natural rubber on a roller, drying moisture in the mixed solution by utilizing high temperature of the roller, and scraping off the dried rubber master batch from the roller; and carrying out mixing and vulcanization treatment on the rubber master batch to obtain the multi-walled carbon nanotube and rubber composite material. The multi-walled carbon nanotube and rubber composite material prepared by the method has relatively high stability, and meanwhile, the abrasion and rolling resistance of the material are reduced.

The invention discloses an early warning system for damage of materials in a high-temperature furnace or a graphitization furnace. The early warning system is suitable for the high-temperature furnace provided with an opposite-penetrating type graphite heater and a multi-layer carbonaceous heat preservation layer. According to the system, the center temperature of a hearth is obtained through an optical pyrometer arranged outside a furnace body, temperature sensors are arranged in heat preservation layers with different thicknesses to obtain the temperature of each heat preservation layer, current transformers or Rogowski current loops are arranged at the head and the tail of a graphite heater, and a low-voltage alternating-current voltmeter is connected to a heating loop; collecting the temperature in the furnace, the temperature of each insulating layer and the current, voltage and power data of a heater; the method comprises the following steps: establishing a heat preservation characteristic reference curve corresponding to furnace temperature and different heat preservation thicknesses in the initial heating stage of equipment, comparing real-time data with the reference curve in the operation process, distinguishing abnormal short circuit and normal aging of a heat preservation material by combining head and tail current distribution and resistance change of a graphite heater, and evaluating equivalent loss of a graphite piece. The system records multi-dimensional data for a long time through the PLC and the upper computer, predicts the residual life of the thermal insulation material and the heater, and realizes online diagnosis and early warning of the state of the material in the furnace.

The application discloses a preparation method and application of a multilayer carbon sphere material. Hollow carbon spheres are obtained by a hard template method, silica is used as a core, and phenolic resin (RF) is used as a shell. The multilayer hollow carbon spheres can be obtained by repeatedly and alternately wrapping the silica and the phenolic resin and then carbonizing and removing the core. By adjusting the particle size of the silica, multilayer carbon spheres with different particle sizes can be obtained. By adjusting the number of layers covered by the phenolic resin, the number of layers of the multilayer hollow carbon spheres can be adjusted. The hollow structure of the hollow carbon spheres reflects and scatters electromagnetic waves, and the interface polarization between the multilayer shells makes the multilayer hollow carbon spheres have excellent absorption effect on electromagnetic waves. The application provides a new preparation method for the multilayer hollow carbon spheres, successfully prepares single-layer, double-layer and three-layer carbon spheres with different particle sizes, the synthesis method is simple, raw material prices are low, and the obtained material has a wide application prospect in stealth technology.