30results about How to "Improve the scattering effect" patented technology

The invention relates to a self-repairing invisible car cover and a preparation method thereof, and relates to the technical field of automobile material processing, and the self-repairing invisible car cover comprises the following components in parts by mass: 20-40 parts of fluorine-containing polyol, 15-30 parts of polyisocyanate, 5-10 parts of a composite chain extender, 10-20 parts of self-repairing microcapsules, 1-3 parts of an initiator and 30-50 parts of a solvent. The preparation method comprises the following steps: preparing a self-repairing coating; coating the surface of the transparent substrate with an adhesive to obtain an adhesive layer, and covering the adhesive layer with a release film to obtain a semi-finished automobile cover; and the self-repairing coating is applied to the face, away from the release film, of the semi-finished automobile cover, heating and curing are conducted, the semi-finished automobile cover with a self-repairing coating is obtained, the self-repairing coating is coated with a protective film, and the self-repairing invisible automobile cover is obtained after curing. The automobile cover has the effect of improving the self-repairing performance of the automobile cover, and the automobile cover has good weather resistance, tensile resistance and puncture resistance.

The invention discloses a lightweight high-strength power cable based on a composite material and application thereof, belongs to the technical field of cable preparation, and aims to solve the technical problem that the lightweight and anti-electromagnetic interference performance of a lightweight cable in the prior art needs to be further improved. The cable comprises a conductor layer, a light shielding layer, a wrapping layer and a composite sheath layer which are sequentially arranged from inside to outside, modified carbon spheres are introduced into a titanium dioxide aerogel structure for filling and loading copper particles, obtained composite aerogel serves as a filling material of the light shielding layer, the modified carbon spheres serve as a cross-linking agent and a filling material of light polyurethane, and the light shielding layer and the composite sheath layer are formed. The composite aerogel and the lightweight polyurethane significantly reduce the density of the cable and significantly improve the lightweight performance of the cable, and through the synergistic cooperation of the copper particles, the titanium dioxide aerogel structure and the hollow carbon spheres, the anti-electromagnetic interference performance of the material is significantly improved.

According to the efficient spraying acid-base washing tower, through the design that the nozzles face upwards, sprayed washing liquid can be diffused and sprayed upwards, the washing liquid sprayed out of the nozzles located on the lower portion collides with the bottom end of a net plate located on the upper portion, and then the washing liquid falls back again after being scattered; at the moment, the scattered and fallen washing liquid and the washing liquid sprayed upwards cover the whole space in a large area, so that the washing liquid diffused in the large area can have more contact area with the ascending waste gas, and the washing effect is improved. Meanwhile, when falling back and scattered washing liquid falls on the water distribution pipeline and the screen plates, the washing liquid is gathered due to blocking of the water distribution pipeline and the screen plates to form large liquid drops, and the liquid drops formed by the upper screen plate fall down through holes in the screen plates and impact the washing liquid which is located below and sprayed upwards in the opposite direction, so that the washing liquid is sprayed upwards. The diffusion condition of the washing liquid is further improved, the gas-liquid contact area is increased, and the washing effect is further improved.

The utility model relates to the technical field of motorcycle lighting lamps, in particular to a multi-light-source transmission type beam concentration lamp which comprises a substrate, light-emitting light sources, a first lens set, a connecting piece and a second lens. The substrate provides installation conditions for the light-emitting source, the first lens group and the connecting piece, the connecting piece is used for connecting the second lens and the substrate, the first lens group is used for collecting light rays emitted by the light-emitting source to the maximum extent, the light rays are evenly distributed in the space, and each lens is optimally designed according to the characteristics of the corresponding light source. The second lens modulates the light in the vertical direction of the lens and does not modulate the light in the horizontal direction, so that the light emitted by each light source can share the second lens, the light beams are overlapped on the second lens to the maximum extent, and the light scattering effect is improved under the condition that the multiple light sources are used at the same time. The transverse size of the second lens is minimized, the compactness and cost reduction of the whole system are facilitated, and the appearance is more harmonious and attractive.

The invention provides an X-ray composite radiation shielding material and a preparation method and application thereof, and belongs to the technical field of radiation protection. The photoelectric effect and the scattering effect of X-rays in the material are remarkably enhanced by using high atomic number elements contained in the metal oxide, so that the transmittance of the X-rays is effectively reduced. Meanwhile, the oxide material has good chemical stability and environmental friendliness, and the toxicity and aging problems caused by a traditional lead-based shielding material can be avoided. The prepared composite radiation shielding material has the advantages of being low in cost, light in weight, easy to process, good in flexibility, non-toxic, environmentally friendly and the like, the shielding efficiency of an X-ray shielding coating reaches up to 70% or above when the X-ray photon energy is 70 kV or below, and the generated secondary reflectance can be reduced by 35-80% compared with lead.

The invention relates to the technical field of metal smelting, and provides an 8-shaped dip pipe and a using method thereof. The 8-shaped dip pipe comprises an ascending pipe and a descending pipe which are communicated with a bottom plate of a vacuum tank; the first partition plate is located between the ascending pipe and the descending pipe, the first partition plate is provided with a first feeding port and a first spraying pipeline, and the first feeding port is communicated with the ascending pipe; the second partition plate is provided with a second feeding hole and a second spraying pipeline; the material mixing channel is located between the first partition plate and the second partition plate, an outlet of the second material spraying pipeline and an outlet of the first material spraying pipeline are both communicated with the material mixing channel, and the material mixing channel is communicated with the downcomer; the first material spraying pipeline and the second material spraying pipeline are both communicated with air supply pipes. By means of the technical scheme, the problem that internal gas is not prone to escaping when liquid flowing circularly is located at the bottom in the vacuum tank is solved.

The application discloses a device for detecting nano-particles by using ultrasonic condensation method, which is characterized by comprising a laser light source (1), a circular tube-shaped ultrasonic transducer (2), a fan (3), a driving circuit (4), an optical lens (5), a photodiode (6) and a detection circuit (7). The device drives nano-particles to condense at a standing wave node position by using an ultrasonic standing wave field, so that the spatial density of the nano-particles is greatly improved, the scattering of the nano-particles to a laser beam is increased, and the detection sensitivity of the nano-particles is remarkably improved.

The invention relates to the technical field of texturing additives for monocrystalline silicon wafers, and discloses a texturing additive for a pyramid textured monocrystalline silicon wafer and a preparation method of the texturing additive. Comprising the following raw materials in parts by mass: 1-1.5 parts of organic sulfonate, 1-2 parts of a polyamine high-molecular compound, 1-2 parts of a high-molecular polymer, 0.5-1 part of a surfactant, 0.2-0.5 part of a composite additive and 90-110 parts of deionized water. The composite additive contains a large number of carboxyl groups, hydroxyl groups and amino groups, the adsorption performance of the texturing additive on the surface of the monocrystalline silicon wafer can be enhanced, then a uniform pyramid structure is formed, the reflectivity is reduced, and the contained modified nano titanium dioxide can form a nano composite film on the surface of the monocrystalline silicon wafer, so that the texturing effect is improved. And the surface roughness and the scattering effect are further improved.

The present invention relates to the technical field of grain drying, and in particular to an agricultural grain circulation drying device, comprising an outer cylinder, a hot air blower is fixedly installed at the bottom of the outer cylinder, a shoveling mechanism and a conveying mechanism, the shoveling mechanism comprising a turntable, the turntable is rotatably connected to the top of the hot air blower, a plurality of shovel-shaped leaves are fixedly connected to the top of the turntable, the shovel-shaped leaves are eccentrically arranged, a plurality of arc plates are fixedly installed on the shovel-shaped leaves, a circular arc groove is arranged on the side of the shovel-shaped leaves away from the shovel blade, and a second nozzle is arranged on the side wall of the shovel-shaped leaves. The present invention gathers grains to a double-layer hollow tube by arranging shovel-shaped leaves, which are conveyed upward by a spiral rod and then fall naturally, thereby realizing continuous grain circulation and effectively avoiding the problem of grain backlog or uneven local drying. The shovel-shaped leaves help to break up the accumulation of grains, and the grains are in contact with the hot air sprayed from the second nozzle, thereby accelerating the transfer of heat and the evaporation of water, and enhancing the drying effect of the grains.

The invention discloses a gallium nitride device and a preparation method thereof, and relates to the technical field of semiconductor devices. The gallium nitride device comprises a sapphire substrate, an AlN nucleating layer, an N-type AlGaN buffer layer, an intrinsic AlGaN active layer, an electron blocking layer and a P-type AlGaN layer which are sequentially stacked from bottom to top, a gradient doping edge stop layer is arranged on the edge of the P-type AlGaN layer, and meanwhile a bottom electrode in ohmic contact with the N-type AlGaN buffer layer and a top electrode in ohmic contact with the P-type AlGaN layer are formed respectively. According to the invention, by optimizing the structural design of the substrate, the nucleating layer, the buffer layer, the active layer, the electron blocking layer, the edge termination layer and the electrode, and combining with the seagull optimization algorithm to accurately regulate and control the preparation process parameters, the comprehensive improvement of the light extraction efficiency, the carrier recombination efficiency, the breakdown voltage and the long-term working stability is realized; and the photoelectric property and the reliability of the gallium nitride device are obviously enhanced.

This invention discloses a mixing device and method for manufacturing PET anti-glare screens. The mixing device includes a mixing device body and a grinding and mixing structure. The mixing device body includes a shell, and a top cover plate is detachably installed on the top of the shell. The grinding and mixing structure includes a multi-level gradient grinding assembly, which includes an upper grinding disc, a middle grinding disc, and a lower grinding disc. This invention integrates the traditional step-by-step process into a continuous process through an integrated grinding and mixing design, greatly shortening the process cycle and improving mixing efficiency. By grinding and mixing the raw materials through the multi-level grinding assembly, the uniformity of nanoparticle dispersion is greatly improved, eliminating microstructural roughness caused by uneven mixing at the source, improving the scattering effect of reflected light, and enhancing the dispersion ability of nano-sized noble metal particles, preventing their agglomeration, resulting in a low coating brightness coefficient and stable polarization ratio.

The invention discloses a substrate for miniature LEDs and a preparation method thereof, and an epitaxial wafer, and relates to the field of semiconductor optoelectronic devices and semiconductor lighting manufacturing. The preparation method of the substrate comprises: providing an initial substrate, coating a negative photoresist, underexposure, and developing to obtain an intermediate, sequentially forming an aluminum oxide film and a silicon oxide film on the surface of the intermediate, and finally removing the negative photoresist to obtain a finished substrate for miniature LEDs; the substrate obtained by the preparation method of the invention can change the light emission angle, increase the external quantum efficiency, and increase the light emission performance of the LED.

This invention belongs to the field of ceramic materials technology and discloses a high-temperature, high-insulation 96 alumina ceramic and its preparation method. The material is made by mixing α-Al₂O₃ powder with a dopant, wherein the dopant is composed of TiO₂ and CaO mixed in a mass ratio of (1-3):(3-1). Its average volume resistivity at room temperature is higher than 10 Ω·cm. 15 The optimal component insulation resistivity can reach 1.75 × 10⁻⁶ Ω·cm at a high temperature of 500°C. 12 The preparation method involves mixing α-Al₂O₃ powder with dopants TiO₂ and CaO according to their doping content; mixing the raw material powder with anhydrous ethanol and then ball-milling; drying and sieving the ball-milled slurry; adding a binder to the obtained powder, sieving it again, granulating it, and pressing it into a green body; firing the green body after debinding to obtain the final ceramic sample. This invention utilizes Ca... 2+ Ti 4+ By doping and modifying the material, 96 alumina ceramics that meet the properties of coulombic electrostatic chucks were prepared. While reducing the sintering temperature, the resistivity was maintained, thus better meeting the practical application requirements.

This invention relates to the field of thermal pipe support technology, and discloses a high-performance, low-thermal-conductivity thermal pipe support and its preparation process. This thermal pipe support, through adjusting the base material ratio and adding functional additives and glass fiber water-absorbing agents, possesses excellent thermal insulation performance and high compressive strength. Magnesium oxide has excellent infrared radiation absorption and scattering capabilities, which can block radiative heat transfer paths at high temperatures, significantly reducing the thermal conductivity. Furthermore, uniform bubbles and magnesium oxide work synergistically to suppress gas thermal convection, thus optimizing thermal insulation performance. The three-dimensional reinforcing structure formed by alkali-free glass fiber within the matrix, combined with the optimization of interfacial bonding performance by fly ash, significantly improves compressive strength. Simultaneously, hyaluronic acid has excellent water absorption properties; it is squeezed out during shrinkage deformation, releasing moisture and effectively reducing plastic shrinkage, thereby improving the strength of foamed cement.

The utility model relates to building template technical field, proposes a kind of building template for concrete building, gradient vibration-suppression hole structure is constructed inside the core layer of damping layer, wherein relatively dense structure, to enhance the reflection and scattering effect of high-frequency vibration, wherein loose structure is conducive to absorption and dissipation low-frequency vibration energy, by controlling the gradient change of pore, realize the efficient suppression of different frequency vibration, set up spiral special-shaped hole in the damping layer, compared with traditional circular hole, can increase the path length and reflection times of vibration wave inside the propagation of damping material, when vibration wave propagates along spiral hole, will constantly occur reflection and refraction, thereby more vibration energy is converted into heat energy and other forms of energy and dissipates, simultaneously the existence of special-shaped hole can also enhance the interaction of damping material and air, further improve damping effect.

This invention discloses a waterproof and UV-resistant outdoor fabric, which is composed of a base fabric and a functional film bonded together with an adhesive. The surface of the base fabric is provided with a waterproof and UV-resistant functional layer. The preparation method of the waterproof and UV-resistant outdoor fabric is as follows: 1) A waterproofing agent layer is applied to the base fabric: ① Prepare a waterproof and UV-resistant finishing solution; ② Immerse the base fabric in the waterproof and UV-resistant finishing solution, performing two dips and two nips; ③ Dry and bake to form a waterproof and UV-resistant functional layer on the surface of the base fabric; 2) The base fabric is bonded to the functional film: ④ Apply an adhesive to the surfaces of the base fabric and the functional film; ⑤ The fabric and film are flatly stacked together and then transferred to a heat press for heat pressing to complete the hot-press lamination, thus obtaining the waterproof and UV-resistant outdoor fabric. The waterproof and UV-resistant outdoor fabric of this invention has good waterproof, UV-resistant, and moisture-permeable functions.

This application relates to a micro-light-emitting structure and a micro-light-emitting device. The micro-light-emitting structure includes: a mesa structure array having a plurality of light-emitting regions spaced apart and a non-light-emitting region surrounding each light-emitting region, and including a first semiconductor layer, a light-emitting layer and a second semiconductor layer, wherein the light-emitting layer and the second semiconductor layer are stacked sequentially on one side of the first semiconductor layer in the plurality of light-emitting regions to form a plurality of mesa structures; and a light scattering structure disposed on the side of the first semiconductor layer near the light-emitting layer in the non-light-emitting region, the light scattering structure being disposed around the mesa structure array in each light-emitting region and configured to scatter the light emitted by the light-emitting layer.

The utility model relates to the technical field of smoke sensor, specifically relates to a power battery smoke sensor, and technical scheme main points include casing, circuit mainboard and top cap, set up the mounting surface on the casing, set up the side window on the opposite side of mounting surface, set up the emission seat, receiving seat, maze structure and bottom window on the casing, the emission seat is used for infrared emission pipe joint, receiving seat is used for infrared receiving pipe joint, based on emission and receiving route, the included angle of emission seat and receiving seat is greater than 90 degrees, the area between emission seat and receiving seat sets up maze structure, bottom window is close to maze structure, and the main circuit board covers the top of maze structure and is set up with the through -hole of position directly opposite bottom window in the middle, the top cap is buckled on the casing and covers circuit mainboard, and the top window of position directly opposite through -hole is set up on the top cap. The utility model discloses through adopt greater than 90 degrees infrared emission receiving route, adopt maze structure, improve the inductive accuracy.

The invention discloses a weather-resistant ethylene-propylene-diene monomer coating which is prepared from the following components in parts by weight: 35 to 40 parts of fluororubber, 10 to 20 parts of polytetrafluoroethylene powder, 20 to 25 parts of organic silicon resin, 80 to 100 parts of polyurethane resin, 3 to 5 parts of nano-silver particles, 15 to 18 parts of mica powder, 1.3 to 2 parts of ultramicro silicon carbide and 10 to 12 parts of modified weather-resistant filler. The invention relates to the technical field of coatings, in particular to an anti-cracking coating. The anti-cracking coating comprises, by weight, 30-35 parts of organic solvent, 0.066-1 part of initiator, 20-22 parts of curing agent, 0.4-1 part of thickening agent, 1.7-2.4 parts of pigment, 0.65-1.2 parts of dispersing agent and 8-10 parts of anti-cracking agent. The uniformly dispersed filler reduces the stress concentration in the coating and improves the flexibility and impact resistance of the coating, so that the coating is not easy to crack and peel under different environmental conditions. And in the aspect of glossiness, the filler is uniformly distributed, so that light reflection is more uniform, the surface gloss of the coating is more attractive and softer, and higher decorative requirements are met.

The invention discloses a multifunctional super fabric for radiation refrigeration and a preparation method thereof.The fabric comprises a fabric layer, a bonding layer and an aerogel layer, and the fabric layer and the aerogel layer are compounded through the bonding layer; the aerogel layer is titanium dioxide aerogel with a three-dimensional pipeline-shaped structure, and a flaky electrostatic spinning fiber membrane containing magnetic core-shell particles is loaded on a framework of the aerogel layer. The multifunctional super fabric for radiation refrigeration has high solar reflectivity (0.90-0.98) and high infrared emissivity (0.90-0.97); the surface temperature lower than the temperature of the base material and the environment can be achieved under the condition of direct solar radiation at noon, and the excellent outdoor radiation refrigeration, flame-retardant and antibacterial capabilities are achieved.

The invention discloses an Mg3Sb2-based semiconductor material for energy conversion and a preparation method thereof, and belongs to the technical field of energy conversion, and the molecular formula of the Mg3Sb2-based semiconductor material is Mg < 3.2 > Bi < 1.3 > Sb < 0.7 >. Mg < 3.2 > Bi < 1.3 > Sb < 0.7 > can generate n-p conduction transformation; when the K is less than 500 K, Mg < 3.2 > Bi < 1.3 > Sb < 0.7 > is an n-type semiconductor; when the voltage is greater than 500 K, Mg < 3.2 > Bi < 1.3 > Sb < 0.7 > is a p-type semiconductor. The preparation method comprises the following steps: uniformly mixing magnesium powder, bismuth powder and antimony powder according to a molar ratio of 3.2: 1.3: 0.7, sealing in a pure argon environment, and carrying out alloying, cold pressing and sintering to obtain the Mg3.2 Bi1. 3Sb0.7. When Bi is doped into the Sb position, the Mg vacancy concentration in the material can be effectively reduced, and the electron concentration can be improved at the same time. The doping not only enables the energy band gap of the material to be narrowed and converted into a narrow-band-gap semiconductor, but also improves the carrier concentration of the material. Under the combined action of the two factors, the electron concentration in the material is remarkably enhanced, and then conversion from an n-type conduction type to a p-type conduction type can be achieved. Therefore, the material has huge application potential in the technical field of energy conversion.

The invention relates to the technical field of materials, and discloses a high-voltage vacuum insulation part material and a preparation method thereof.The high-voltage vacuum insulation part material is prepared by taking PA66 as a matrix and assisting with a modified fiber material and the like through mixing and melt extrusion processes, and hyperbranched polymer molecular chains are modified on the surfaces of mullite fibers, so that the high-voltage vacuum insulation part material is obtained. The prepared modified fiber material can generate hydrogen-bond interaction with a PA66 molecular chain in a melting process, further entangled with the PA66 molecular chain and extend into each area of a PA66 matrix to form an interwoven miniature three-dimensional network structure, so that the mullite fiber can efficiently play a role in transmitting a load, the mechanical property of the PA66 is enhanced, and the service life of the mullite fiber is prolonged. A hyperbranched molecular chain on the surface of the mullite fiber contains a rigid chain link, so that the defect of PA66 serving as a straight-chain molecule is overcome, and the mechanical property of the mullite fiber is further improved.

The invention provides a radiation refrigeration fabric preparation method, which comprises: S1, carrying out hydrophilic treatment on one side surface of a fabric to obtain a fabric layer; s2, Ag-TiO2 at BaSO4 is added into waterborne polyurethane, stirring is conducted for 10-30 min at the speed of 800-1000 r / min, so that the Ag-TiO2 at BaSO4 and the waterborne polyurethane are evenly mixed, the fabric layer subjected to hydrophilic treatment is coated with the mixture, then pre-baking is conducted for 1-3 min at the temperature of 100-110 DEG C, baking is conducted for 2-5 min at the temperature of 130-155 DEG C, and the radiation refrigeration fabric is prepared. According to the radiation refrigeration fabric, the surface of the fabric is coated with Ag-TiO2-coated BaSO4 to achieve the refrigeration purpose, in the Ag-TiO2-coated BaSO4, BaSO4 serves as a hollow core layer, TiO2 serves as a shell layer, nano Ag particles are embedded in TiO2, and the radiation refrigeration function is achieved through the synergistic effect of BaSO4, TiO2 and nano Ag particles.

The invention provides a shading high-barrier composite film capable of replacing aluminizing and a preparation method thereof. The composite film sequentially comprises a base layer, a shading layer, an ultraviolet-proof layer and a protective layer from outside to inside. The base layer is a polyvinyl chloride film layer, the shading layer is prepared by mixing montmorillonite nano clay, a high-molecular polymer and a nanoscale titanium dioxide dispersion liquid, the ultraviolet-proof layer is an ultraviolet light absorber formed by mixing a bio-based material and a benzophenone or triazole compound, and the protective layer is a glycol terephthalate layer. Wherein the bio-based material is prepared from sugarcane extract, anthocyanin and chitosan according to a specific proportion. The preparation method comprises the following steps: preparing the base layer, the shading layer, the ultraviolet-proof layer and the protective layer, and performing hot-pressing compounding to obtain the composite film. In addition, specific parameters of the shading layer coating process, the ultraviolet-proof layer spraying process and the protective layer hot-pressing compounding are also introduced. The composite film has shading and ultraviolet-proof functions, can replace a traditional aluminum laminated film, and has a wide application prospect.

This invention belongs to the technical field of cast aluminum alloys, and discloses a high-strength, low-thermal-conductivity cast rare-earth aluminum alloy suitable for brazing and its preparation method. The rare-earth aluminum alloy is composed of the following components by weight percentage: RE: 9~11%, RE being La and / or Ce; Mn: 0.8~1.2%; Mg: 0.4~1%; impurities: ≤0.20%; balance being Al. This invention also discloses a method for preparing the rare-earth aluminum alloy. The synergistic effect of the elements in the rare-earth aluminum alloy of this invention results in a high eutectic temperature, high tensile strength, and low thermal conductivity, meeting the requirements of hard brazing processes. The method of this invention is simple and low-cost. The aluminum alloy of this invention is suitable for manufacturing components in new energy vehicles, such as refrigerant manifolds and refrigerant storage tanks, which have stringent requirements for low heat dissipation, high strength, and weldability.

The utility model discloses a multi-light-source indirect lighting anti-glare lamp which is characterized in that the multi-light-source indirect lighting anti-glare lamp comprises a main lamp part and an auxiliary lamp part which are movably connected with each other, the main lamp part is provided with a main lamp holder and a first lamp set, and the first lamp set is installed in the main lamp holder and used for emitting focused light; the auxiliary lamp part is provided with an auxiliary lamp holder and a second lamp group; a second opening is formed in one end of the auxiliary lamp holder; an adapter hole is formed in the other end of the auxiliary lamp holder, and the main lamp holder is movably connected to the adapter hole of the auxiliary lamp holder; the second lamp set is fixedly connected to the interior of the auxiliary lamp holder and emits non-focused light from the second opening of the auxiliary lamp holder. In conclusion, high-brightness direct illumination needed by the spotlight can be formed, indirect auxiliary illumination on a dark area can also be formed, and therefore glare is prevented, and eyes are better protected.

This invention discloses a low speckle contrast, high reflectivity aerogel optical material, its preparation method, and its applications. The low speckle contrast, high reflectivity aerogel optical material comprises a transparent aerogel matrix serving as an optical framework; and light-scattering nanoparticles dispersed therein. The aerogel optical material has a first surface and a second surface arranged opposite to each other in the thickness direction. From the first surface to the second surface, the light-scattering nanoparticles exhibit a graded distribution in particle size, with the particle size gradually increasing. This invention utilizes the ultra-low refractive index of the aerogel to suppress Fresnel interface reflection, improve luminous efficiency, and provide a high refractive index difference. Through a "sedimentation-gel synergy" process, a gradient structure with a continuous particle size distribution in the thickness direction is constructed in situ within a single matrix, simultaneously achieving extremely low speckle contrast (<4%) and high light utilization (average visible light reflectivity >90%), while also possessing advantages such as ultra-light weight and good environmental stability.

The present invention discloses an n-type bismuth telluride-based thermoelectric material and a preparation method thereof, and relates to the field of thermoelectric materials. The present invention includes process steps such as component configuration, high-energy ball milling, SPS sintering, etc., and adopts a method of adding a certain specific gravity of a second phase material to a bismuth telluride matrix material. The prepared thermoelectric material is an n-type bismuth telluride-based thermoelectric material of Bi2Te 2.7 Se 0.3 +0.5wt% MgAgSb; the carrier concentration is adjusted by anion alloying and adding the prepared MgAgSb second phase, the grain boundaries are increased, and micro-nano powders of different sizes are obtained through high-energy ball milling combined with SPS sintering process, which effectively enhances the scattering of long and short wavelength phonons and obtains lower thermal conductivity. The prepared thermoelectric materials have good application prospects in the medium and low temperature range.

The present application relates to the technical field of textiles, in particular to an antibacterial fabric based on graphene-polyamide composite fiber and a production process thereof. The present application overcomes the problem of poor antibacterial performance and durability of the antibacterial fabric. In the present application, modified graphene, Ag / ZnO nanoparticles and polyamide masterbatch are melt-extruded to obtain modified polyamide fibers; composite ultraviolet-resistant agent, modified antioxidant, modified moisture-absorbing agent and polyester masterbatch are melt-extruded to obtain modified polyester fibers; finally, the modified polyamide fibers, the modified polyester fibers, cotton fibers and bamboo fibers are mixed, twisted, heat-set and blended to obtain the antibacterial fabric. In the present application, the modified graphene and the Ag / ZnO nanoparticles can synergistically improve the antibacterial performance of the antibacterial fabric; the polyamide masterbatch, the polyester masterbatch and the cotton fibers can jointly improve the mechanical properties of the antibacterial fabric; the composite ultraviolet-resistant agent, the modified antioxidant, the modified moisture-absorbing agent and the bamboo fibers can improve the ultraviolet resistance and moisture-absorbing and air-permeability of the antibacterial fabric.

The invention discloses a high-impedance graphene heat-conducting film and a preparation method thereof, the high-impedance graphene heat-conducting film contains high-temperature-resistant insulating particles, and the melting point of the high-temperature-resistant insulating particles is greater than or equal to 1500 DEG C; and the particle size distribution of the high-temperature-resistant insulating particles meets the condition that D95 is less than or equal to 3 microns. The preparation method comprises the following steps that dry graphene oxide powder and desalted water are mixed to prepare graphene oxide slurry with the carbon-oxygen ratio smaller than 2.9, the graphene oxide slurry and high-temperature-resistant insulating particles are evenly mixed and then coated, and the high-resistance graphene oxide heat conduction film is obtained. The high-impedance graphene oxide heat-conducting film is sequentially subjected to low-temperature heat treatment, medium-temperature heat treatment, high-temperature heat treatment and calendering treatment, and then the high-impedance graphene heat-conducting film is obtained. According to the method, industrial large-scale preparation of the high-impedance graphene heat-conducting film is realized, and application of the graphene heat-conducting film to a heating device is facilitated.