222results about How to "Inhibition" patented technology

The invention discloses a diffractive optical waveguide and a preparation method thereof, and a head-mounted display device, and relates to the technical field of augmented reality, and the preparation method of the diffractive optical waveguide comprises the steps: obtaining a target eye box range adaptive to a target crowd; according to the human eye parameters of each user group in the target group, splitting the target eye box range to obtain sub-eye box ranges adapted to each user group; diffractive optical waveguides adapted to the user groups are prepared based on the sub-eye box ranges, and the area of a coupled-out grating in each diffractive optical waveguide is smaller than the area of a coupled-out grating of an optical waveguide designed for covering the target eye box range. The optical efficiency and uniformity of the diffractive optical waveguide can be ensured, and the diffractive optical waveguide is prevented from generating obvious rainbow lines, so that the use experience of a user is improved.

The invention discloses a preparation method and application of an iron-doped molybdenum disulfide / polymer-based composite solid-state electrolyte, and relates to the technical field of solid-state batteries. After the iron element is doped, defects are introduced into the structure of the modified molybdenum disulfide, phase change is induced, dissociation of the lithium salt is promoted through synergism of the modified molybdenum disulfide and the iron element, and more free lithium ions are released; and meanwhile, the proportion of an amorphous region of the polymer electrolyte is increased, so that the ionic conductivity is improved, and the oxidation resistance is enhanced. In addition, the iron-doped molybdenum disulfide can effectively catalyze decomposition of lithium salt anions, and construction of a uniform and stable solid electrolyte interface (SEI) layer on the surface of the electrode is facilitated. The all-solid-state lithium metal battery assembled based on the modified solid electrolyte shows excellent electrochemical performance.

The present application relates to a kind of staggered jet microchannel heat sink, including cover layer, manifold layer, jet layer and microchannel layer stacked in turn, cover layer is equipped with fluid inlet and fluid outlet, manifold layer is used to shunt the fluid of fluid inlet, jet layer is equipped with array distribution jet orifice and backflow hole, jet orifice and backflow hole staggered distribution, microchannel layer is equipped with heat dissipation groove, heat dissipation groove is equipped with array distribution columnar needle fin, and form needle fin microchannel, the axial direction of columnar needle fin and the jet direction of jet orifice are parallel to each other;Fluid emitted by jet orifice is boiled and carries out transverse flow in needle fin microchannel and absorbs heat, based on the staggered distribution of jet orifice and backflow hole, the transverse flow fluid in needle fin microchannel presents staggered counterflow, and flows to fluid outlet by backflow hole.Compared with prior art, the present application improves the temperature uniformity of heat dissipation object, effectively suppresses the generation of local hot spot and greatly improves heat exchange efficiency.

This invention belongs to the technical field of aluminum powder passivating agents, specifically relating to an aluminum powder passivating agent and its preparation method. The preparation method of the aluminum powder passivating agent includes the following steps: heating a solvent, adding anchoring functional monomers, including styrene-based phosphoric acid, hydroxyethyl methacrylate phosphate, and 2-methacryloyloxyethyl phosphate, stirring until homogeneous, continuing to add mixed monomers, stirring until homogeneous, adding a mixed solution of initiator and solvent dropwise, allowing the reaction to complete, adding solvent to adjust the solid content after the reaction, cooling to room temperature, and obtaining the aluminum powder passivating agent. This invention provides a novel aluminum powder passivating agent and its preparation method. This passivating agent forms a stable protective layer through surface passivation, effectively blocking the contact between aluminum powder and water, inhibiting hydrogen generation, avoiding can bulging, and exhibiting high stability.

This invention belongs to the field of pharmaceutical technology, specifically relating to the application of a small-molecule antioxidant in mitigating vascular damage in type 2 diabetes. To develop an effective solution for addressing vascular damage in diabetic patients, this invention, through research, discovered that Lithospermoside can specifically inhibit XO in the cell membrane anchoring state, effectively reducing ROS production in the thoracic aorta, thereby significantly reducing BUN, E-selectin, MDA, and UACR. Simultaneously, it inhibits the fluorescence intensity of nitrotyrosine staining, thus alleviating vascular endothelial damage in type 2 diabetes with persistent hyperglycemia. It exerts an antioxidant effect to slow down diabetic vascular damage and protect blood vessels, providing an effective material basis and new ideas for the prevention and treatment of vascular damage in type 2 diabetes.

This invention relates to a resin composition for injection molding, comprising a poly(3-hydroxyalkanoate) resin. The poly(3-hydroxyalkanoate) resin comprises at least one copolymer of 3-hydroxybutyrate units and other hydroxyalkanoate units. The average content of 3-hydroxybutyrate units in the poly(3-hydroxyalkanoate) resin is 92 mol% or more and 99 mol% or less. The poly(3-hydroxyalkanoate) resin, obtained by gel permeation chromatography using chloroform solvent, has a polystyrene-converted weight-average molecular weight of 210,000 or more and 380,000 or less, and the proportion of components with a weight molecular weight of 200,000 or less in the weight molecular weight distribution is 35 wt% or more and 60 wt% or less.

Disclosed are a phosphorus-containing compound, a nonaqueous electrolyte, and a lithium ion battery. In the present application, an additive for a lithium ion battery is provided, the phosphorus-containing compound has a structure shown in formula (I), wherein the R1 and R2 groups are as described in the context of the present application, the phosphorus-containing compound is added in a nonaqueous electrolyte, and the internal resistance of the battery can be significantly reduced, particularly the internal resistance when the battery is fast-charged.

The present application belongs to the technical field of oral care, and particularly relates to an oral care composition and a preparation method thereof. The oral care composition comprises, by mass percentage, chitosan oligosaccharide 0.1-0.3%, sea hao polysaccharide 0.08-0.14%, forskolin 0.07-0.12%, corn sprout extract 0.05-0.09%, thickening agent 1-3%, humectant 40-50%, and the balance being water. The oral care composition of the present application can effectively inhibit the activity of glucosyltransferase, inhibit the production of dextran, interfere with the formation process of dental plaque, and reduce the adhesion sites of pathogenic bacteria in the oral cavity. In addition, the composition of the present application can promote the proliferation and repair of oral mucosa epithelial cells, and help repair oral mucosa damage. Furthermore, the use of each component in the composition of the present application can balance the oral microbial flora, while achieving the effect of inhibiting pathogenic bacteria and improving the oral environment.

The application relates to the technical field of tunnel construction, and discloses a combined segment structure, which comprises a UHPC segment and concrete test blocks, a plurality of concrete test blocks are arranged on the outer side surface of the UHPC segment in sequence along the curvature direction of the UHPC segment, the UHPC segment is provided with main reinforcement and stirrups, the main reinforcement is provided with a plurality of strips along the curvature direction of the UHPC segment, a plurality of stirrups are sequentially sleeved on the plurality of main reinforcement and are connected with the main reinforcement through binding, the concrete test blocks are provided with transverse steel bars and longitudinal steel bars, the transverse steel bars extend to the outside of the concrete test blocks and are overlapped with the stirrups, and the longitudinal steel bars extend to the outside of the concrete test blocks and are overlapped with the main reinforcement. Compared with the prior art, the structure design realizes optimal control of material cost by filling the concrete test blocks in the non-key stress area under the premise of hardly sacrificing the core performance of UHPC materials such as strength, durability and stress condition, and effectively eliminates the core economic obstacle in the popularization process of the UHPC shield segment.

This invention discloses a Litsea cubeba extract, its preparation method, and its applications, relating to the field of pharmaceutical compound technology. The Litsea cubeba extract has the structural formula shown in Formula I: (Formula I). ​​This Litsea cubeba extract is isolated from the Litsea cubeba plant. This novel compound can significantly inhibit NO production in an LPS-induced RAW264.7 cell inflammation model; alleviate the immune-inflammatory response in an in vitro 3D skin model of atopic dermatitis; inhibit epidermal thickening and repair skin barrier function; and reduce the inflammatory response by inhibiting the PI3K / Akt signaling pathway. It has clinical application potential in the treatment of atopic dermatitis and can be used to prepare anti-atopic dermatitis drugs, showing promising application prospects.

The application provides a gradient temperature difference processing method for preventing and controlling rancidity and deterioration of rice bran decoction pieces, comprising the following steps: sequentially subjecting newly harvested rice bran to low-temperature rapid cooling, medium-temperature roasting, high-temperature roasting and second ultra-low-temperature rapid cooling after removing impurities by primary screening, so as to prevent and control rancidity and deterioration of rice bran decoction pieces. The application utilizes rapid and strong temperature difference change to prevent and control the reaction after grinding contact oxidation, destroys the autoxidation system of rice bran, effectively prevents and controls the generation of oxidized toxic substances and the breeding and pollution of harmful microorganisms, and ensures the safety and effectiveness of medication.

A compressor drive device includes an inverter device including an inverter circuit that converts direct current into alternating current and a control portion, and a compressor including a motor connected to the inverter circuit and a piston that reciprocates in a cylinder under the action of the motor. The control portion includes a multi-phase PWM signal generation portion that can set a plurality of carrier frequencies for driving the compressor, and a bottom dead center detection portion that detects a bottom dead center of the piston in the compressor. In a case where the carrier frequency is switched from a high frequency to a low frequency during rotation of the compressor, the timing of the switching is made to be the bottom dead center of the compressor. Thus, generation of overcurrent can be well suppressed when the carrier frequency is switched.

The application belongs to the technical field of methanol preparation, and particularly relates to a device and a preparation method for preparing methanol by combining carbon dioxide hydrogenation with chemical chain combustion, which comprises a power generation system, an electrolytic cell, a chemical chain combustion reactor, a pure oxygen supplement combustion chamber and a methanol reaction unit. The power generation system is connected with the electrolytic cell. Oxygen generated by electrolysis of the electrolytic cell is connected with the chemical chain combustion reactor through a first pipeline. Oxygen generated by electrolysis of the electrolytic cell is connected with the pure oxygen supplement combustion chamber through a second pipeline. The chemical chain combustion reactor is connected with a raw material pipeline. The top of the chemical chain combustion reactor is connected with the pure oxygen supplement combustion chamber through a third pipeline. The pure oxygen supplement combustion chamber is connected with the methanol reaction unit through a fourth pipeline. Hydrogen generated by electrolysis of the electrolytic cell is connected with the methanol reaction unit through a fifth pipeline. Reaction products are discharged through a sixth pipeline.

The invention discloses a processing method for a copper-clad ceramic substrate, which relates to the technical field of copper-clad ceramic substrate processing, and comprises the following steps of: taking a pre-treated copper-clad ceramic substrate, introducing nitrogen, and carrying out layered progressive micropore processing on an exposed aluminum oxide ceramic substrate of the pre-treated copper-clad ceramic substrate through picosecond laser to form micropores; each micropore is divided into an inlet layer, a middle layer and an outlet layer from top to bottom; the layer number of the micropores, the thickness of each layer of the micropores and the pulse width are controlled, and a light spot and long-focal-depth lens is adopted; adjusting monopulse energy and frequency parameters of picosecond laser, and punching an inlet layer; adjusting monopulse energy and frequency parameters of picosecond laser, and punching the middle layer; and adjusting monopulse energy and frequency parameters of the picosecond laser, and punching the outlet layer to obtain the copper-clad ceramic substrate. In the middle layer, the monopulse energy is gradually increased, and it is ensured that the material is evenly removed; at the inlet layer and the outlet layer, energy is reduced, and cracks caused by stress generated instantly when the material is punctured are avoided.

The utility model provides a combustion nozzle for mixing various waste gases, and belongs to the field of industrial waste gas emission. And the problem of insufficient combustion caused by non-uniform mixing of various waste gases is solved. The multi-hole nozzle comprises a nozzle shell, a multi-hole outer pipe, a multi-hole inner pipe, a fan blade pipe, a vacuum generator and a combustion air gun. An air inlet is formed in the side wall of the nozzle shell; a porous outer pipe and a porous inner pipe are arranged in the nozzle shell, the porous outer pipe is arranged on the outer side of the porous inner pipe, and the top of the porous outer pipe and the top of the porous inner pipe are both connected with the shell cover plate; a spraying opening is formed in the bottom of the nozzle shell; the nozzle shell is connected with a furnace end through a spraying opening, and a negative pressure chamber and a waste gas mixing chamber are sequentially arranged in the furnace end in the gas circulation direction. An air gun connector is arranged outside the furnace end; a fan blade pipe is arranged on the outer side of the porous inner pipe, and a plurality of inclined partition plates are arranged in the fan blade pipe in the circumferential direction at equal intervals. The waste gas mixing device is mainly used for fully mixing various waste gases.

The application discloses a whitening and freckle-removing composition containing white tomato and chases yellow grass, a preparation method and application thereof, and belongs to the technical field of food, wherein the whitening and freckle-removing composition is composed of white tomato powder and chases yellow grass powder with a weight ratio of 1-3:2-7. The preparation method comprises the following steps: (1) beating, separating, concentrating and drying white tomatoes to obtain white tomato powder; (2) soaking chases yellow grass in acidic water, performing solid-liquid separation, concentrating and drying the obtained clear liquid to obtain chases yellow grass powder; and (3) mixing the white tomato powder and the chases yellow grass powder. The application utilizes the combination of white tomatoes and chases yellow grass, and improves the preparation process of chases yellow grass, so that the two components produce a synergistic effect in inhibiting tyrosinase activity and inhibiting melanin production.

This application relates to a high-nickel cathode material and its preparation method, and a lithium-ion battery. The chemical formula of the high-nickel cathode material is Li. σ Ni a Co b Mn c M1 x M2 y M3 z O 2+α Wherein, 0.80<σ<1.20, a+b+c+x+y+z=1, 0.7<a<1.0, 0<b<0.05, 0<c<0.3, 0<x<0.3, 0<y<0.3, 0<z<0.3, 0<α<0.1, M1, M2, and M3 are each independently including at least one of Al, Co, Zr, Ti, Mg, Y, La, Sr, Ba, W, Mo, Nb, and Si, and M1, M2, and M3 are all different; the high-nickel cathode material includes a high-nickel material matrix and a coating layer. Cu-Kα rays are used to perform XRD measurements on the high-nickel material matrix and the high-nickel cathode material, respectively. The intensity of the (104) diffraction peak appearing in the diffraction angle range of 44-45° is recorded as I. b (High-nickel material matrix) and I c (High-nickel cathode material), the unit of diffraction peak intensity is counts, let the diffraction peak intensity difference P = I c -I b 0 < P < 1000. The high-nickel cathode material provided in this application has better high-temperature cycling performance and a low DC internal resistance growth rate.

This invention proposes an adaptive virtual impedance droop control method, system, device, and medium, relating to the field of droop control. The method includes: calculating the standardized reactive power of each local node and neighboring node based on the equivalent output impedance and reactive power droop coefficient; generating a correction amount for the virtual impedance based on the accelerated consensus algorithm and the standardized reactive power of each local node and neighboring node; adjusting the virtual impedance in the distributed grid topology according to the correction amount of the virtual impedance to obtain the adjusted dynamic virtual impedance; calculating the virtual impedance voltage drop based on the adjusted dynamic virtual impedance; calculating the feedforward compensation voltage reference value; calculating the common compensation amount of the preset virtual leader node and the local compensation amount of each local node and neighboring node to obtain the total voltage compensation command; adjusting the feedforward compensation voltage reference value according to the total voltage compensation command to obtain a voltage stabilization scheme, using the dynamic virtual impedance as the power distribution scheme.

The utility model discloses a multi-purpose car cleaning machine which comprises a rail moving type portal frame, two sets of bucket elevators are arranged and connected to the rail moving type portal frame in a lifting mode, and the top discharging ends of the two sets of bucket elevators are connected with telescopic discharging barrels. The bottom feeding ends of the two groups of bucket elevators are respectively connected with an open carriage cleaning head and an open container cleaning head; the material conveying mechanism is horizontally arranged on the rail moving type portal frame and located between the two sets of bucket elevators, the bottom ends of the two telescopic discharging barrels are connected to the material conveying mechanism, and the discharging end of the material conveying mechanism is connected with a dust cover; the dust removal assembly is fixed on the track moving type portal frame, the dust removal assembly comprises a negative pressure dust remover and a spraying dust suppressor, the negative pressure dust remover is used for removing dust at the discharging end of the material conveying mechanism, the spraying dust suppressor is used for suppressing dust of the cleaning head, and the negative pressure dust remover and the spraying dust suppressor are both fixed on the track moving type portal frame. And the applicability is high.

The application relates to a scale-inhibiting alloy and a preparation method thereof and a scale-inhibiting sheet manufactured from the scale-inhibiting alloy. The scale-inhibiting alloy comprises the following components: 55wt%-70wt% of Cu, 15wt%-30wt% of Zn, 5wt%-15wt% of Ni, 0.5wt%-3wt% of Si, 1wt%-5wt% of P, 0.001wt%-0.05wt% of a modifying element, and the balance of inevitable impurities, wherein the modifying element is one or more of B, Ti and Zr. The scale-inhibiting alloy adds the Si element for strengthening, so as to improve the mechanical properties and corrosion resistance; the Zn element is added as a negative electrode and the P element is added as a positive electrode, the alloying forms alpha phase+beta phase+multi-element brittle compound phase, can well excite the active current, and prevents the generation of water scale. The scale-inhibiting alloy has low production cost, meets the comprehensive requirements of cost, processing performance, corrosion resistance, mechanical properties, health and market acceptance of water treatment products, and has a good application prospect.

The present disclosure relates to an LED lighting device. The LED lighting device includes a luminaire housing forming a mounting surface, a connection plate configured to be electrically connectable to an external power source and fixed to the luminaire housing, and a plurality of LED modules fixed to the luminaire housing in a state of being electrically connected to the connection plate, each of the LED modules including an LED light source. The connection plate and the LED modules are disposed on the same plane with respect to the mounting surface.

The utility model relates to the technical field of wires and cables, in particular to a halogen-free cable with an anti-cracking structure, which comprises a conductor, an insulating layer, a filling layer, an anti-cracking layer and a sheath layer which are sequentially arranged from inside to outside, the anti-cracking layer consists of a corrugated elastomer layer and a reinforcing piece, the corrugated elastomer layer is coated on the outer surface of the insulating layer, and the reinforcing piece is coated on the outer surface of the insulating layer. The wave-shaped elastomer layer provides a telescopic space, absorbs mechanical stress and prevents stress from being concentrated on the sheath layer through periodic distribution of wave crests / wave troughs of an axial wave structure when the cable is bent or subjected to external force, so that generation of cracks is inhibited, and spirally wound fibers / metal wires of the reinforcer are embedded into the wave troughs to form constraint. Excessive deformation of the corrugated elastomer layer is limited, tensile strength is improved, radial cracking expansion is prevented, the sheath layer and the anti-cracking layer are welded, the sheath layer and the corrugated elastomer layer are welded through a co-extrusion process, a traditional interlayer interface is eliminated, interlayer stripping caused by thermal expansion and cold contraction or external force is avoided, and the service life is prolonged.

The application discloses a carbon deposition resistant nickel-based catalyst for a dry reforming reaction of methane and a preparation method of the catalyst, and the preparation method comprises the following steps: step one, mixing lanthanum nitrate hexahydrate, aluminum nitrate nonahydrate and glycine, and adding deionized water, and stirring until a transparent solution is formed; step two, evaporating the transparent solution to form a gel; step three, drying the gel, igniting, and calcining to obtain a fluffy powder; grinding the powder to obtain a modified alumina carrier; step four, loading nickel on the modified alumina carrier by taking nickel nitrate hexahydrate as a precursor, so as to obtain the carbon deposition resistant nickel-based catalyst for the dry reforming reaction of methane.

The present application can provide a laminate and a display device including the same, the laminate having a resin layer containing a light scattering agent on a substrate layer, and suppressing generation of a defective portion in the resin layer. The present application provides a laminate and a display device including the same, the laminate including a substrate layer and a resin layer disposed on at least one surface thereof, the resin layer containing a light scattering agent (A), when a contact angle of the substrate layer with respect to diiodomethane is set as θs (°), and a contact angle of the resin layer with respect to diiodomethane is set as θr (°), the following formula is satisfied: |θs - θr| ≤ 21.

The application provides a strain of Rhodococcus ZJUHULJT1 and application of the strain in prevention and treatment of paratyphaceae root-knot nematodes, and belongs to the technical field of biological prevention and treatment of root-knot nematodes. Rhodococcus The Rhodococcus (sp.) ZJUHULJT1 is preserved in the China Center for Type Culture Collection, and the preservation number is CCTCC NO: M 20251182; the Rhodococcus ZJUHULJT1 can significantly inhibit the infection and reproduction of root-knot nematodes, reduce the number of rice root knots, promote the synthesis of defense-related hormones of rice roots, and improve the disease resistance of rice; through the multiple inhibition of paratyphaceae root-knot nematodes, the Rhodococcus ZJUHULJT1 can be applied to the prevention and treatment of rice root-knot nematodes, has good prevention and treatment effect, and provides a new technical means for the pollution-free reduction of paratyphaceae root-knot nematode diseases.

The present invention aims at achieving labor saving, and achieving low cost of introduction and suppression of the preparation of the moving path, thereby reducing the introduction barrier of the collaborative robot accompanying the movement. The robot system has a robot (10) and a control device (20), the robot (10) has a free dolly (12) and a mechanical arm (11) placed on the free dolly (12), and the control device (20) controls the mechanical arm (11). The control device (20) controls the mechanical arm (11) in order to perform a predetermined task, and controls the mechanical arm (11) in order to move the robot (10) itself.

The application discloses a model prediction control-based temperature control system and method of a plasma incinerator, and the system comprises a model prediction control module, a chromatographic temperature detector and a plasma torch; the model prediction control module is used for constructing a prediction model and obtaining a control output of a plasma incinerator hearth temperature based on the prediction model; the chromatographic temperature detector is used for measuring a temperature value of the plasma incinerator hearth and feeding back the temperature value to the model prediction control module; the model prediction control module is further used for correcting the control output based on the temperature value to obtain a next-time prediction output of the plasma incinerator hearth temperature; and the plasma torch controls the opening degree based on the control output to complete temperature control. The application can guarantee that the hearth temperature of the plasma incinerator is in a stable state during combustion, effectively suppresses the generation of harmful flue gas, realizes energy saving and emission reduction, and has high practicability.

The invention discloses a sex attractant for yellow rice borers as well as a preparation method and application of the sex attractant, and relates to the technical field of agricultural pest monitoring, prevention and control. The sex attractant comprises an active component which is prepared from (Z)-dodecyl-9-ene-1-yl acetate, (E)-dodecyl-9, 11-diene-1-yl acetate and (7E, 9Z)-dodecyl-7, 9-diene-1-yl acetate, and the sex attractant is prepared from an active component which is prepared from the following components of (Z)-dodecyl-9-ene-1-yl acetate, (E)-dodecyl-9, 11-diene-1-yl acetate and (7E, 9Z)- According to the sex attractant disclosed by the invention, aiming at the current sugarcane area dominant population, the three active components have a synergistic effect, so that the trapping activity of the current sugarcane area dominant population is remarkably improved, and the problems that the trapping activity is low and the specificity is poor due to the fact that a control object is not matched with the dominant population in the existing sex attractant product are solved. Field trials show that the trapping quantity of the sex attractant provided by the invention on the yellow rice borers is obviously higher than that of a control group, the sex attractant has extremely high population specificity, and accurate monitoring and efficient trapping and killing of yellow rice borer populations can be realized.

Provided is an electronic device that achieves both stability of electrical contact between terminals and sealing performance. A power supply unit 101 includes a power supply adjustment board 10 and a holder 100 that holds the power supply adjustment board 10, an accommodation member 20 that accommodates the power supply unit 101 inserted from an opening 20a, and a cap member 23 that closes the opening 20a, wherein a positive electrode terminal 42 and a negative electrode terminal 43 are arranged side by side in the accommodation member 20, a positive electrode terminal 14 and a negative electrode terminal 15 are arranged side by side on one end side in the power supply unit 101, a locking mechanism P that locks the power supply unit 101 is provided in the accommodation member 20 such that the positive electrode terminal 14 and the negative electrode terminal 15 of the power supply unit 101 are brought into electrical contact with the positive electrode terminal 42 and the negative electrode terminal 43 of the accommodation member 20, and power supply lines 27 and 29 are disposed to penetrate the cap member in a sealed state and configured for connecting an external power supply to the power supply adjustment board 10.

The invention relates to the technical field of composite films, in particular to a flame-retardant composite film and a preparation method thereof. The composite film is of an ABA type symmetrical three-layer co-extrusion structure, and functional division and synergistic interaction are achieved by concentrating a main flame-retardant function on a core layer (B layer) and distributing hydrolysis resistance and mechanical enhancement functions on a surface layer (A layer). The layer A comprises crystalline polyester, reinforcing master batch and an interface reinforcing agent; the layer B comprises crystalline polyester and composite flame-retardant master batch; the preparation method mainly comprises the following steps: respectively preparing the reinforced master batch and the composite flame-retardant master batch; respectively mixing the raw materials of the layer A and the layer B, drying and melting; co-extruding and casting through a three-layer co-extrusion die head with gradient temperature field control, and quenching a cast sheet; and preheating the cast sheet, and then carrying out synchronous two-way stretching, heat setting and cooling rolling. The film prepared by the invention has excellent halogen-free flame retardance, outstanding damp-heat aging resistance and high mechanical strength, and is suitable for the field with strict requirements on safety and durability.