4089 results about "Composite membrane" patented technology

The invention discloses a hydrophobic-hydrophilic Janus water collecting film and an efficient preparation method thereof, and belongs to the field of water collecting materials. An electrostatic spinning process is adopted, and a hydrophobic polymer is accurately deposited on the surface of a hydrophilic substrate in the form of a nanofiber array, so that the Janus composite membrane with an asymmetric wetting gradient structure is successfully constructed. The unique double-sided wettability difference drives the liquid drops to realize directional transmission, and the core mechanism of the liquid drops is derived from capillary force regulation and control caused by interfacial wetting potential energy difference. The Janus membrane shows excellent performance in the aspect of air moisture trapping, the ultra-fast moisture absorption characteristic and the surface regeneration capacity are achieved, and compared with a traditional single-layer hydrophilic membrane, the water collecting efficiency is remarkably improved by 110%. A one-step forming process is adopted for preparation, the diameter of the nanofibers is controllable, complex post-treatment procedures are not needed, and energy consumption required by equipment is low. The high-performance water collecting film has important application value in the fields of atmospheric water taking in arid regions, dehumidification of precise instruments and the like.

The invention relates to the technical field of polymeric membrane materials, and particularly discloses an antistatic polyethylene composite membrane and a preparation method thereof. Comprising the following raw materials in parts by weight: 100 parts of low-density polyethylene, 5-9 parts of high-density polyethylene, 10-20 parts of maleic anhydride grafted polyethylene, 8-15 parts of a polyvinyl alcohol modified material, 3-5 parts of antistatic modified carbon black, 0.5-1 part of an antioxidant and 1-2 parts of a dispersing agent, the polyethylene composite film has excellent dispersibility, can effectively enhance the mechanical properties of the polyethylene composite film through the synergistic effect of physical filling and chemical grafting, forms a layer of conductive network structure, namely a conductive film, on the surface of the material through the combined effect of the polyethylene composite film and the antistatic agent, prevents the generation and accumulation of static electricity, and has good compatibility among the raw materials. And the material has excellent mechanical property and antistatic property.

The invention relates to the technical field of high polymer material preparation, and discloses a bamboo fiber graft modified full-biodegradable composite membrane material preparation process which comprises the following steps: firstly, performing hot mixing and cooling on dried bamboo fiber powder, anhydrous citric acid, choline chloride, activated zinc oxide and pentaerythritol to prepare a bamboo fiber modified premix; then mixing the biodegradable polyester resin with the premix; adding the mixture into an extruder, injecting epoxidized soybean oil into a barrel through a liquid metering device, and performing melt extrusion granulation under a vacuum exhaust condition; and finally carrying out blow molding to form the film. Through in-situ reaction extrusion of multi-component synergism, surface grafting of bamboo fibers, chain extension of a polyester matrix and interface chemical bonding of the bamboo fibers and the polyester matrix are achieved, interface compatibility is effectively improved, degradation of the material in the processing process is inhibited, and the mechanical property and thermal stability of the composite film material are remarkably improved; the process is efficient and environment-friendly, and the cost is controllable.

The invention discloses a nanofiltration membrane for extracting lithium from salt lake brine with a high magnesium-lithium ratio and a preparation method of the nanofiltration membrane, and belongs to the technical field of nanofiltration composite membranes. The preparation method of the nanofiltration membrane comprises the following steps: first-time interfacial polymerization treatment, second-time interfacial polymerization treatment and post-treatment. The nanofiltration membrane with a double-layer lithium ion permeation channel is constructed through coupling of secondary interfacial polymerization and a B15C5 modification process, and stable permeation performance of the membrane is guaranteed while high magnesium ion rejection rate and high magnesium-lithium separation factor are realized through synergistic modification of crown ether and secondary interfacial polymerization. The nanofiltration membrane disclosed by the invention shows excellent performance in a real salt lake brine test, and in practical application, the membrane can effectively treat a complex brine system with a high magnesium-lithium ratio; and in a 24-hour continuous test, long-term stability is also shown, and an efficient, stable and feasible solution is provided for lithium extraction of the salt lake brine with the high magnesium-lithium ratio.

The invention relates to the technical field of composite film preparation, in particular to a multi-layer co-extrusion nano ceramic coating high-barrier medicine packaging composite film and a preparation method thereof.The multi-layer co-extrusion nano ceramic coating high-barrier medicine packaging composite film comprises a base material layer, a gas barrier layer, a bonding transition layer and a nano ceramic functional coating; the base material layer comprises the following components in parts by mass: 80-100 parts of biaxially oriented polypropylene; 20 to 30 parts of metallocene linear low density polyethylene; 5 to 8 parts of nano titanium dioxide; 0.5 to 1 part of beta-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid; and 0.3 to 0.6 part of calcium stearate. Through the multi-layer co-extrusion and gradient curing technology and the five-layer co-extrusion technology, it is ensured that the thickness of a base film is uniform and interlayer bonding is firm, the adhesive force of the coating is enhanced through plasma surface treatment, and activity retention and uniform distribution of functional components are guaranteed through the segmented curing strategy of the nano ceramic coating; compared with a traditional hot-pressing compounding or solvent coating process of the composite film, the energy consumption and the solvent residue risk are greatly reduced, meanwhile, the production efficiency and the product consistency are improved, and large-scale application is provided for medicine packaging.

The invention relates to the technical field of packaging films, and particularly discloses a heat-resistant polyethylene composite packaging film and a preparation method thereof.The polyethylene composite packaging film comprises an inner layer, a middle layer and an outer layer, the inner layer is prepared from, by mass, 100 parts of linear low-density polyethylene, 28-32 parts of polypropylene and 8-10 parts of hydrotalcite modified blending materials, the middle layer comprises the following raw materials in parts by weight: 100 parts of low-density polyethylene, 40-60 parts of linear low-density polyethylene, 3-5 parts of a coupling agent and 0.5-1 part of an antioxidant, the outer layer comprises the following raw materials in parts by weight: 100 parts of modified PA6, 20-30 parts of metallocene polyethylene and 5-8 parts of a compatilizer, functional gradient distribution is realized by adopting layered extrusion of three-layer co-extrusion, and PA6 and polypropylene have a synergistic effect, so that the composite film has excellent heat resistance, and the service life of the composite film is prolonged. The hydrotalcite and the graphene oxide have a synergistic effect, the layered structure effectively obstructs oxygen and water vapor, and the obtained polyethylene composite packaging film is good in barrier property and has excellent mechanical property and heat resistance.

The invention belongs to the technical field of water electrolysis hydrogen production diaphragms, and relates to coating slurry for a composite diaphragm in an alkaline electrolytic cell and a preparation method of the coating slurry. The coating slurry comprises a high-molecular polymer, an inorganic hydrophilic oxide, a polymer electrolyte, a pore-foaming agent and an organic solvent. The high-molecular polymer is polysulfone, and the inorganic hydrophilic oxide is titanium dioxide; and the polymer electrolyte is acacia gum. And the pore-foaming agent is polyvinylpyrrolidone. Titanium dioxide is used as a filler, so that the hydrophilicity of the hydrophobic polysulfone membrane can be improved, and the transfer of hydroxyl ions is facilitated. Hydroxyl, amino and other hydrophilic groups of the acacia gum are migrated to a membrane-water interface, and the groups and a membrane matrix are combined to form a hydrogen bond network, so that the stability and the water adsorption capacity of the membrane are enhanced, and the composite membrane with low surface resistance, smooth surface, compact coating and good mechanical capacity is obtained. The nylon and the acacia gum are adopted, cost is low, and large-scale production is facilitated.

The invention belongs to the technical field of genetic engineering and biological medicine, and particularly discloses a cascade response type nano-particle with a microenvironment remodeling function and a preparation method and application of the cascade response type nano-particle. The nanoparticle provided by the invention adopts a bionic hybrid membrane engineering strategy: an inner core is formed by loading an exosome inhibitor on a nano material, and the surface is covalently coupled with M2 type macrophage specific targeting peptide; the outer layer coats a macrophage membrane and active oxygen response type liposome composite membrane layer through a co-extrusion technology, and is loaded with a TLR agonist. Animal experiments show that after being injected through caudal vein, the nano-particles are enriched at a tumor site in a targeted manner through homing receptors such as membrane surface integrin alpha4beta1 and the like, and outer membrane cracking is triggered in a high-ROS tumor microenvironment, so that space-time controlled release of a TLR agonist and targeted phagocytosis of an exosome inhibitor by macrophages guided by a targeted peptide are realized. The anti-tumor synergistic effect is achieved through multiple regulation and control mechanisms, and an effective treatment strategy is provided for tumor immunotherapy.

The invention belongs to the technical field of side slope structures, and particularly discloses a side slope structure with an automatic stabilizing system, which comprises a side slope body, a sensing layer, a water absorption layer, a drainage layer and a control part. The sensing layer comprises a distributed optical fiber sensor and is used for collecting strain information data and temperature and humidity information data of a soil body. The water absorption layer is of a layered structure and is used for storing excessive water in pores of the soil body. The drainage layer comprises a drainage pipeline and a pump, the drainage pipeline is located at the bottom of the water absorption layer, and the pump is connected with the input end of the drainage pipeline. And the control part is used for receiving the strain information data and the temperature and humidity information data, analyzing and processing the data, and starting the pump to drain water when monitoring that the water content or the pore water pressure exceeds a set threshold value. Through multi-layer cooperative work of the sensing layer, the water absorption layer and the water drainage layer, the integrated slope stabilization scheme of multi-parameter monitoring, composite film water absorption and intelligent water drainage is achieved, and the reliability and efficiency of landslide early warning and prevention are greatly improved.

The invention discloses a partitioned multifunctional metal double-cavity vacuum coating process and system, and belongs to the technical field of material surface treatment. The process comprises the steps of base material pretreatment, double-cavity preparation, vacuum inspection, first cavity bottom layer deposition, vacuum transfer, second cavity functional layer deposition and cooling, the double cavities are provided with corresponding target materials respectively, and parallel operation and vacuum seamless transfer are supported; the system comprises double coating cavities, a vacuum transmission channel, a vacuum acquisition and control module, a coating deposition module, a workpiece bearing module and a process parameter regulation and control module, and each of the double cavities is provided with a multi-target mounting rack and carries a real-time monitoring unit and an intelligent control system. Integrated preparation of the composite film layer and synchronous production of multifunctional workpieces are achieved, operation gaps are eliminated, the compactness and adhesive force of the film layer are improved, parameter deviation and the reject ratio are reduced, and batch production requirements are met.

The invention belongs to the technical field of membrane material preparation and water treatment, and discloses a La-MOF-COOH / AO-PAN composite membrane material and a preparation method and application thereof, and the preparation method of the membrane comprises the following steps: preparing a PAN membrane; preparing an AO-PAN membrane; the preparation method comprises the following steps: preparing La-MOF-COOH; and the preparation of the La-MOF-COOH / AO-PAN film is carried out. The composite membrane material is composed of modified polyacrylonitrile fibers, metal lanthanum and an organic ligand. Amino groups and hydroxyl groups in amidoximated PAN participate in hydrogen bonds and covalent interaction, so that the interfacial compatibility and stability of La-MOF-COOH and AO-PAN are improved, agglomeration of La-MOF-COOH filler is avoided, the structural uniformity, stability and functionality of the La-MOF-COOH / AO-PAN composite membrane are improved, and the composite membrane has a good application prospect.

The invention relates to a composite fiber membrane, an electromagnetic wave sensing and shielding driver and application thereof, and provides a fiber-based composite membrane which has photo-thermal and moisture stimulation deformation and electromagnetic wave sensing and shielding functions. The composite fiber membrane has the advantages of light weight, flexibility, high machinability and the like, and has wide application prospects in the fields of electromagnetic wave shielding, electromagnetic wave sensing, flexible electronic equipment, intelligent wearable equipment, soft robots and the like.

A pervaporation composite membrane belongs to the technical field of membrane separation. The pervaporation composite membrane comprises a porous substrate, a middle membrane layer and a separation membrane layer which are sequentially stacked, the average pore size of the porous substrate is greater than or equal to 250nm; the average pore size and porosity of the middle film layer are smaller than those of the porous substrate, and the middle film layer has the organic matter affinity characteristic; the separation membrane layer has the hydrophobic characteristic and the organic matter selective permeation characteristic. The middle membrane layer is beneficial to improving the problems of seepage holes, difficulty in spreading, uncontrollable thickness of the separation membrane layer and the like in the solid-liquid interface preparation process, ensures the defect-free preparation of the separation membrane layer, and is beneficial to improving the permeability of the pervaporation composite membrane to organic matters.

The invention relates to the technical field of biomedical materials, and discloses an electret electrostatic therapy membrane and a preparation process thereof.The electret electrostatic therapy membrane is prepared from, by mass, 15%-20% of fluorinated polyether ester, 10%-20% of a composite nano-fiber material, 10%-20% of a composite nano-fiber material, 10%-20% of a composite nano-fiber material and the balance water. 1%-2% of carboxymethyl chitosan; 2-5% of nano cerium oxide particles with the particle size of 50-100 nm; 0.5-1.0% of graphene quantum dots, the particle size of which is 5-10 nm; 1%-2% of sodium hyaluronate; the components are prepared into a film through an electrostatic spinning method, electret performance is given to the film through a charge injection process, finally, the film body is attached to a flexible silica gel adhesion layer, and the flexible silica gel adhesion layer is externally coated with a peelable protective film so that the structural integrity can be kept before the flexible silica gel adhesion layer is used. The composite membrane body disclosed by the invention shows excellent adhesion, charge activation capability and thermal response performance in applications of electrostatic therapy, dielectric assisted stimulation and the like, and has good multi-scene adaptability and clinical application potential.

This invention belongs to the field of passive radiative cooling materials, specifically relating to a thermal management film that integrates both radiative cooling and heating functions, and its preparation method. It is characterized by preparing a black PPY modified cotton as the heating surface and a white PMMA / NaH2PO2 composite film as the cooling surface, which are then combined by coating and drying to produce a double-sided thermal management film capable of both heating and cooling. This invention addresses the difficulty people have in regulating their temperature in hot or cold environments. The entire temperature regulation process is environmentally friendly and energy-saving, and the preparation method is simple, making it suitable for large-scale production.

The invention discloses a micro fluid heat dissipation device based on a shell inner wall groove structure and electronic equipment. The heat dissipation device comprises a heat absorption runner module, a heat release runner module and a driving element. The heat absorption flow channel module is of a multi-layer composite film structure. The heat release runner module comprises a sealing film and a groove runner formed in the inner side face of the electronic equipment shell. And the sealing film is fixed on the inner side surface of the shell of the electronic equipment and covers and seals the groove flow channel. The channels formed in the inner side face of the electronic equipment shell serve as heat release runners of the heat dissipation device, the heat dissipation effect of the liquid cooling heat dissipation device of the electronic equipment is improved by means of the good heat conduction performance of the electronic equipment shell and the large contact area between the electronic equipment shell and the external environment, and long-time stable operation of the electronic equipment is guaranteed. The heat absorption flow channel module adopts a multi-layer composite film structure, only one layer of film is arranged between the cooling medium and the heating element, the heat transfer path is short, and the cooling capacity of the heat dissipation device on the heating element is improved.

The invention relates to a mesoporous LLZO / PVDF-HFP composite solid electrolyte membrane as well as a preparation method and application thereof. The electrolyte membrane comprises a polymer matrix PVDF-HFP and a disordered mesoporous LLZO filler dispersed in the polymer matrix PVDF-HFP, and the mass ratio of LLZO to PVDF-HFP is (1: 7)-(7: 1). The composite membrane is prepared through a solvent exchange-freeze drying method, and the process comprises the following steps: dissolving PVDF-HFP in an organic solvent, adding mesoporous LLZO, stirring to form uniform slurry, coating the slurry, and carrying out solvent exchange and freeze drying treatment to obtain the membrane. The obtained electrolyte membrane is stable in structure and excellent in ionic conductivity, can be applied to a lithium metal battery as a solid electrolyte membrane material, and remarkably improves the cycling stability and rate capability of the battery.

The invention discloses a polytetrafluoroethylene ceramic membrane and a preparation method and application thereof, and the preparation method comprises the following steps: (1) adding polytetrafluoroethylene and a binder into water, and carrying out first mixing to obtain polytetrafluoroethylene slurry; adding a carbon nanotube and a dispersing agent into water, and carrying out secondary mixing, so as to obtain a carbon nanotube dispersion liquid; (2) carrying out third mixing on the carbon nanotube dispersion liquid and the polytetrafluoroethylene slurry to obtain a membrane preparation liquid; and (3) coating the surface of a ceramic support with the membrane preparation liquid, drying, and carrying out microwave sintering. The PTFE / ceramic composite membrane is prepared by microwave sintering, so that the sintering time and the production period are obviously shortened, and the production efficiency and the energy utilization rate of the product are obviously improved; the prepared PTFE / ceramic composite membrane is narrow in pore diameter and uniform in pore diameter distribution, has good hydrophobicity and oil-water separation performance, can effectively intercept 30-200nm nanoparticles, and has excellent anti-pollution capacity and stable separation performance for water-in-oil emulsions with different concentrations.

The diamond coated glass structure may include a glass substrate in which the deposited nanocrystal diamond is coated on the glass substrate. A layer of ultra-nanocrystalline diamond may be deposited on the deposited nanocrystalline diamond. The combination of the deposited nanocrystal diamond and ultra-nanocrystal diamond may have a surface roughness of less than 9 nanometers RMS.

The invention discloses a visual analysis-based steel-wood combination template welding seam quality detection method, and relates to the related field of machine vision and image processing, the method comprises the following steps: collecting image data of a steel-wood combination template surface welding seam, the images being divided into two types of welding seam defect-free and welding seam defect-having; in view of the reflection difference of different materials of the steel-wood combined template, preprocessing the collected surface weld seam image of the steel-wood combined template, adjusting the brightness distribution of the image surface, and extracting weld seam features; marking welding seam features, training a welding seam quality detection model, and storing model parameters with the best performance as a pre-training model; in a real production environment, inputting a steel-wood combined template surface welding seam image shot in real time into the pre-training model, carrying out deep analysis on welding seam characteristics, and outputting a detection result; and according to a detection result of the model, evaluating the welding seam quality of the steel-wood combined template, and completing a quality detection report. And the welding seam quality detection precision and efficiency are improved.

The invention is applicable to the technical field of proton exchange membranes, and particularly relates to a perfluorosulfonic acid proton exchange composite membrane which is prepared by the following steps: preparing a perfluorosulfonic acid resin solution: dissolving the perfluorosulfonic acid resin solution in a mixed solvent to form a membrane casting solution; impregnating and filling: impregnating a porous base membrane in the obtained perfluorinated sulfonic acid resin solution, and keeping at 20-80 DEG C for 1-120 minutes; drying and forming: taking out the impregnated film, and drying to form a composite film; and protonation treatment: treating the composite membrane in an acid solution, and washing to be neutral to obtain the perfluorosulfonic acid proton exchange composite membrane. According to the invention, the problems of deformation and damage of the battery in operation are effectively avoided; meanwhile, the high proton conductivity is ensured, so that the ion transmission efficiency is maintained; the introduction of the ePTFE porous skeleton enhances the membrane body and reduces the use amount of the perfluorinated sulfonic acid resin at the same time, the composite membrane is compact in structure and balanced in performance, and the durability and reliability of the fuel cell are greatly improved.

The invention belongs to the technical field of membrane separation, and particularly relates to a composite membrane as well as a preparation method and application thereof. The composite membrane comprises a supporting membrane, and the supporting membrane is provided with holes; the polydopamine film layer is arranged in the supporting film or on the surface of the supporting film; the metal organic framework is arranged on the surface of the polydopamine film layer. The composite membrane provided by the invention has high permeability and excellent oil-water mixture separation performance, anti-pollution performance and stability.

The invention relates to the field of biodegradation, and discloses a full-biodegradable composite film as well as a preparation method and application thereof. The composite film comprises a barrier layer, a protective layer and a bonding layer, the protective layer is arranged on the surface layer of the composite film, and the barrier layer and the protective layer are bonded through the bonding layer; matrix resin B of the bonding layer is selected from degradable resin grafted polar monomers and / or degradable resin grafted monomers containing groups capable of reacting with hydroxyl; the matrix resin C of the barrier layer at least contains polyglycolic acid with multimodal molecular weight distribution. The composite film provided by the invention has excellent barrier property and biodegradability, and also has good interlayer peel strength and heat sealing strength.

The invention discloses a copper surface micro-etching coarsening solution for a fine circuit as well as a preparation method and application of the copper surface micro-etching coarsening solution, and relates to the technical field of printed circuit board manufacturing. The copper surface micro-etching coarsening solution for the fine circuit is prepared from, by mass concentration, 60 g / L to 100 g / L of sulfuric acid, 40 g / L to 60 g / L of hydrogen peroxide, 0.5 g / L to 2 g / L of zinc sulfate, 10 g / L to 30 g / L of copper ions, 0.5 g / L to 1 g / L of pyridine heterocycle-containing Schiff base, 10 g / L to 100 g / L of ethyl alcohol, 1 g / L to 3 g / L of 2-mercaptobenzothiazole, 1 g / L to 5 g / L of methionine and 1 g / L to 5 g / L of polyacrylamide. According to the copper surface micro-etching coarsening solution, the 2-mercaptobenzothiazole and the methionine in the copper surface micro-etching coarsening solution can enable the copper surface to form a honeycomb structure under the low micro-etching amount, the zinc sulfate and the pyridine heterocyclic ring-containing Schiff base can form a composite film layer with copper ions on the surface of the honeycomb structure, and the interlayer binding force is improved.

The invention discloses a composite film based on light-biological synergistic gradient degradation and a preparation method thereof, the composite film sequentially comprises a light response layer, a transition layer and a biological response layer from outside to inside, and the light response layer comprises a polycaprolactone matrix, a tetraphenylporphyrin iron photosensitizer and anatase type TiO2 nanorods; the transition layer is a gradient blend of polylactic acid and modified starch; the biological response layer comprises polyhydroxyalkanoate and bacterial cellulose nanofibers; through the design of the three-layer gradient structure and the construction of the bionic microchannel, the synergistic effect of light degradation, hydrolysis and biodegradation is realized; the composite membrane has excellent mechanical properties and environmental adaptability, the degradation period can be accurately regulated and controlled within 30-180 days, and the soil degradation rate within 60 days reaches 91% or above; the preparation method comprises the processes of electrostatic spinning, gradient co-extrusion and bacterial cellulose in-situ culture. The material can be widely applied to the fields of agricultural mulching films, food packaging and the like, and the problems that a traditional degradable film is poor in mechanical property and uncontrollable in degradation are solved.

The invention relates to the technical field of membrane separation, in particular to a composite forward osmosis membrane based on mussel bionic interface enhancement and a preparation method thereof. The preparation method comprises the following steps: immersing a base material in a dopamine hydrochloride solution for oscillation reaction to obtain a modified base material; the surface of the modified base material is coated with a membrane casting solution in a blade coating mode, then phase inversion is carried out, the residual solvent is removed, then airing is carried out, and the composite forward osmosis membrane based on mussel bionic interface enhancement is obtained. By introducing the mussel bionic polydopamine intermediate layer, the long-standing technical contradictions of poor interfacial compatibility and weak binding force between the hydrophobic substrate and the hydrophilic separation layer are ingeniously solved, and the internal concentration polarization effect is remarkably inhibited. The prepared composite membrane has the advantages of high water flux, low salt reverse flux, stable structure and the like, and has wide application prospects in the fields of water treatment and substance separation.

The invention provides a preparation method of a high-flux stable-selection anti-fouling nanofiltration membrane, which comprises the following steps: carrying out amination modification on a nano material by an activation method to prepare a modified nano material; piperazine, an acid absorbent and the modified nano material are added into deionized water to be mixed, and a water phase solution is prepared; the preparation method comprises the following steps: mixing trimesoyl chloride and normal hexane to prepare an organic phase solution; immersing the polyethersulfone-based membrane into the water phase solution, draining, inversely immersing into the organic phase solution, and carrying out interfacial polymerization reaction to generate a polyamide layer to obtain a composite membrane; and then carrying out post-treatment on the composite membrane to obtain the composite membrane. The membrane has high permeability, high selectivity and strong anti-pollution performance.

The invention discloses a gas sampling mechanical arm for mining area ecological restoration carbon sink evaluation, and relates to the technical field of mining area gas detection equipment. The device comprises a base, a driving arm is mounted at the top of the base, a storage seat is mounted at the top of the base, and a sampling shell is arranged in the storage seat; a storage assembly is arranged in the sampling shell and comprises a fixing plate installed in the sampling shell. Through collaborative design of the storage assembly and the adjusting assembly, the mining area gas sampling efficiency and continuity are remarkably improved, the storage assembly adopts four sets of aluminum foil composite film storage bags and is matched with a disc structure driven by a rotating shaft, multi-period gas samples can be automatically grouped and stored at the same sampling position, and the sampling efficiency is greatly improved. The adjusting assembly drives the disc to rotate through the driving motor, so that the inclined groove and the sealing plug are accurately aligned, rapid switching of the storage bags is achieved under the action of negative pressure, multiple sets of data can be collected through single sampling, and meanwhile energy consumption and time cost of repeated positioning of the mechanical arm are reduced.

The invention provides a multispectral camouflage infrared wavelength selection thin film and a preparation method thereof, and belongs to the technical field of spectral thermal radiation management, and the preparation method comprises the following steps: screening a material with directional emission in a wave band of 8-14 microns as a directional emission layer material according to an optical constant of a thin film material in the wave band of 3-25 microns; a directional emission layer material is combined with a lossless dielectric material and a metal material to construct a cascaded Fabry-Perot resonant cavity structure; according to the arrangement sequence and the optical constant of each layer of film, taking the thickness of each layer of film as an optimization variable, and utilizing an optimization algorithm taking a quality factor function as a judgment basis to carry out iterative calculation to obtain the optimal thickness of each layer of film; and according to the structure of the multi-layer composite film and the optimal thickness of each layer of film, depositing each layer of film material on the substrate by adopting a magnetron sputtering process to prepare the multi-spectral camouflage infrared wavelength selection film. According to the scheme, the optimization efficiency of the film layer is improved, and efficient thermal management is realized while the multispectral camouflage performance is maintained.

The invention provides a micro-nano dual-scale synergistically enhanced MXene-based conductive composite film and a preparation method thereof, belongs to the technical field of multifunctional electromagnetic shielding composite materials, and aims to solve the technical problems that MXene is poor in structural stability and low in binding strength with a base material. The preparation method of the composite membrane comprises the following steps: dropwise adding a pyrrole monomer into an MXene solution to prepare an MXene nanosheet internally doped with PPy, and loading the MXene-PPy nanosheet onto a nanofiber membrane to prepare an MXene-based nanofiber conductive membrane; the MOF microspheres and a hydrophobic agent are mixed to prepare a hydrophobic solution, and the MXene-based nanofiber conductive film is soaked in the hydrophobic solution. The micro-nano dual-scale synergistically enhanced MXene-based conductive composite film prepared by the invention has excellent electromagnetic shielding performance, good hydrophobic property, light weight, softness and foldability, and can be flexibly applied to electromagnetic shielding in various complex environments.