47results about How to "Short preparation cycle" patented technology

The application relates to a low-eutectic solvent-based gel electrolyte, a preparation method and a zinc-air battery, and belongs to the technical field of metal-air batteries. Choline chloride and 2-methyl-1,3-propanediol are prepared into a deep eutectic solvent, then zinc acetate dihydrate solution, acrylic acid monomer, a crosslinking agent and a photoinitiator are sequentially added, the mixture is uniformly mixed, photopolymerization is carried out, and a low-eutectic solvent-based gel is obtained. The electrolyte is obtained by soaking the gel in a mixed solution of potassium hydroxide and zinc salt. The zinc anode protection capability and the low-temperature adaptability of the gel electrolyte can be improved. The gel electrolyte is assembled into a zinc-air battery together with a zinc electrode and an air electrode, and the cycle life and the operation stability of the battery in a low-temperature environment can be effectively improved.

This invention discloses an antifouling membrane made of lanthanum-loaded carbon nanomaterials suitable for phosphorus recovery in wastewater, its preparation method, and its applications. The invention involves loading lanthanum carbonate octahydrate onto the surface of multi-walled carbon nanotubes (MWCNTs) to form lanthanum-loaded carbon nanomaterials (La@MWCNTs), which are then deposited onto the surface of a polyethersulfone-based membrane using vacuum filtration to form a self-supporting membrane. The prepared lanthanum-loaded carbon nanomaterial antifouling membrane possesses both phosphorus removal and recovery capabilities, exhibiting high efficiency in phosphorus removal from water. This facilitates phosphorus elution and recovery, effectively solving the problems of lanthanum-loaded carbon nanomaterial aggregation and recovery, and effectively avoiding the risk of lanthanum-based adsorbent leakage during phosphorus removal. Furthermore, the lanthanum-loaded carbon nanomaterial antifouling membrane operates within a low-pressure range, exhibiting low energy consumption and effectively mitigating membrane fouling caused by humic acid. It shows promising application prospects in wastewater phosphorus recovery and eutrophication control.

This invention provides a temperature-sensitive, environmentally friendly microcapsule and its preparation method, relating to the field of polymer materials. The microcapsule is composed of chitosan, cellulose derivatives, gelatin, and dopamine. The microcapsule can achieve different cross-linking structures depending on the component ratios, and can controllably release the core substance within a temperature range of 90-150℃. The materials provided by this invention eliminate toxic reagents, and the microcapsules are all environmentally friendly materials, causing no environmental pollution. The microcapsule preparation method is characterized by temperature sensitivity and controllability, being green, environmentally friendly, and pollution-free, with a simple preparation method suitable for large-scale industrial production. Utilizing temperature-sensitive, biodegradable, and comprehensively environmentally friendly materials, it has broad application prospects in catalyst coating, drug coating, and other fields, meeting the needs of multiple sectors.

This invention relates to a copper oxide material, its preparation method, and its application. The preparation method includes: mixing an inorganic base, a dispersant stabilizer, and a copper salt in water to form a raw material solution; carrying out a precipitation reaction; washing and drying the precipitated product to obtain the copper oxide material; the pH value of the raw material solution is 13.10-14; the copper salt includes copper acetate. This invention also provides the copper oxide material obtained by the above preparation method and its application in the electrocatalytic reduction of carbon dioxide. The preparation method is simple and controllable, and the prepared copper oxide material exhibits high electrocatalytic carbon dioxide reduction performance.

The invention belongs to the technical field of piston shoe preparation, and particularly relates to a low-cost preparation method of a copper-steel composite bimetal piston shoe blank for a high-pressure plunger pump. According to the method, the characteristic that the melting point of copper alloy is lower than that of a steel base material is utilized, a steel material is machined into a sliding shoe base blank with a cavity, then a prefabricated copper alloy blank is loaded into an inner cavity of the steel base blank, and a layer of protective borax covers the inner cavity of the steel base blank; heating in an inert atmosphere protection resistance heating furnace or a reducing atmosphere protection resistance heating furnace to melt the copper alloy into a liquid state, preserving heat for a certain time in a high-temperature environment to infiltrate and diffuse the liquid-state copper alloy to the surface of the solid-state steel base, and then discharging and cooling to solidify the copper alloy in the cavity; and finally, a metallurgically bonded copper-steel bimetal composite sliding shoe blank is prepared.

The invention provides a diamond grinding tool based on silicon carbide wafer processing and a preparation method and application, the diamond grinding tool comprises a grinding pellet piece and a grinding disc, the grinding pellet piece is provided with Ni powder, a metal binding agent, a ceramic binding agent, a pore forming agent and a wetting agent, diamond abrasive particles and the metal-ceramic binding agent are adopted as raw materials and are mixed with Ni, a certain amount of pore forming agent is added, and the mixture is stirred to be uniform; the preparation method comprises the following steps: sintering for 20 minutes at high temperature and high pressure in a high-temperature mold, removing pressure after sintering, cooling to 810 DEG C, preserving heat for 10 minutes, then cooling to 550 DEG C, and preserving heat for 10 minutes, so that sintering shrinkage can be effectively prevented; compared with a conventional metal-ceramic bond diamond grinding tool, the multi-nickel metal-ceramic bond diamond grinding tool has the advantages that the material removal rate is increased by 18.3%, the overall level of the grinding process and technology can be improved, the quality of a processed product is improved, the preparation period is short, the product cost can be greatly reduced, and the economic benefit is high.

The application discloses a SnTe-based thermoelectric material and a preparation method thereof, and belongs to the technical field of thermoelectricity. The application adopts high-purity metal elements as raw materials, and the raw materials are mixed according to a stoichiometric ratio, and then a cast ingot is obtained through a melting reaction after vacuum packaging. Subsequently, the cast ingot is subjected to high-temperature annealing treatment. After the cast ingot subjected to the high-temperature annealing treatment is ground into powder, a dense block-shaped SnTe-based thermoelectric material is formed through discharge plasma sintering. The chemical formula of the SnTe-based thermoelectric material is Sn 2.9‑X W X Te 2.9 -(In2Te3) 0.03 -(Cu2Te) 0.18 The application significantly improves the thermoelectric figure of merit of the SnTe-based thermoelectric material and improves the thermoelectric performance of the SnTe-based thermoelectric material by doping tungsten elements in the SnTe matrix and compounding the two metal compounds of In2Te3 and Cu2Te.

The invention discloses a methylamine formamidino perovskite single crystal, a preparation method thereof and an X-ray detector, and belongs to the technical field of perovskite single crystal X-ray detectors. Methyl iodide amine, formamidino hydriodate and lead iodide are used as raw materials, anhydrous acetic acid is used as an additive, growth is carried out in a solvent through a seed crystal method, and the methylamine formamidino perovskite single crystal is obtained. Anhydrous acetic acid and formamidine generate hydrogen-bond interaction, formamidine is pulled to enter crystal lattices, so that phase separation is eliminated, acetate and Pb coordinate to delay formation of a lead-iodine framework, the speed of methylamine and formamidine entering the crystal lattices is balanced, meanwhile, the stability of a methylamine formamidine perovskite precursor solution is improved, stable growth of methylamine formamidine perovskite single crystals is achieved, and the methylamine formamidine perovskite single crystals are obtained. The single crystal has the advantages of high crystallinity, low defect density, large size and favorable X-ray response performance. The methylamine formamidine perovskite single crystal is high in controllability in the growth process, and the preparation method is high in operability, simple and easy to implement, short in preparation period, low in equipment requirement and low in cost.

This application discloses a calcium-based carbon dioxide adsorbent, its preparation method, and its application, relating to the field of adsorbent technology. The preparation method of the calcium-based carbon dioxide adsorbent includes the following steps: obtaining calcium hydroxide, an unsaturated organic compound, magnesium oxide, and aluminum oxide; mixing the calcium hydroxide, unsaturated organic compound, magnesium oxide, and aluminum oxide and adding them to a solvent; heating and stirring to obtain a mixed suspension, wherein the unsaturated organic compound is an organic acid or an organic aldehyde; drying the mixed suspension to obtain a dried powder; subjecting the dried powder to medium-temperature combustion to obtain a calcium-based carbon dioxide adsorbent precursor, wherein the medium-temperature combustion temperature is 400–600°C; and subjecting the calcium-based carbon dioxide adsorbent precursor to a first high-temperature calcination to obtain the calcium-based carbon dioxide adsorbent, wherein the first high-temperature calcination temperature is 700–1000°C. This application solves the technical problem of poor adsorption performance of existing calcium-based carbon dioxide adsorbents.

The invention discloses a preparation method of pure mycelia, the pure mycelia and application. The method comprises the following steps: S1, preparing a mycelia solid culture medium; S2, preparing a mycelia paste culture medium; S3, forming the mycelia paste culture medium and fermenting mycelia; according to the method, a continuous, compact and thickness-controllable pure mycelium layer is formed on the surface of a pasty fluid culture medium in a manner of combining solid culture and pasty fluid culture, and a mycelium biological material with excellent physical properties can be obtained without adopting a bracket or an adhesive material. The preparation method has the advantages of simple steps, no need of a complex sterilization mode, short preparation period, low cost, capability of forming large-area pure mycelia at one time, suitability for large-scale industrial production, mild preparation conditions, greenness and environmental protection. The prepared pure mycelium can be applied to mycelium leather or mycelium meat, does not need an adhesive when being used for the mycelium leather, is excellent in material physical performance, does not need chemical or plant adhesives when being used for the mycelium meat, and is good in taste and high in nutrition.

The invention belongs to the technical field of waste photovoltaic panel recovery, and particularly relates to a method for extracting high-purity silicon and silver from a waste photovoltaic panel, which comprises the following steps: disassembling and separating glass and a backboard assembly attached with a battery piece; performing high-pressure crushing and dry-method sorting: performing ultrahigh-pressure jet crushing on the back plate assembly by adopting an ice-based mixed abrasive material, and then performing three-stage series cyclone separation to obtain a silicon powder primary product and a silver-containing material; refining molten salt and recovering silver: after pickling the silicon powder primary product, placing the silicon powder primary product in a NaOH-KOH low-temperature mixed molten salt for reaction, and separating to obtain high-purity silicon powder; and the reacted fused salt is dissolved and filtered, and high-purity silver powder is precipitated and calcined from filtrate to be recycled. According to the method, the silicon powder and the silver powder are recycled through a recycling three-step method, traditional pure physical separation and chemical separation are abandoned, a more advanced alkali etching method is adopted in the reaction process, and the loss rate of silicon is very low, so that the method is simple in process, good in condition, short in preparation period and suitable for industrial production.

This invention discloses a sample quality control method for a carbon fiber vacuum flow process, comprising: coating a carbon fiber sample onto a mold; fixing a reinforcing inner skeleton onto the carbon fiber sample; installing a positioning insert on the mold, positioning and connecting a mounting plate on the positioning surface of the positioning insert, fixing the mounting plate to the carbon fiber sample or the reinforcing inner skeleton; and drying the carbon fiber sample mounted on the mold. The advantages of this invention are: by adding a reinforcing inner skeleton to the back of the carbon fiber sample, the rigidity of the carbon fiber sample itself can be improved, enhancing its resistance to deformation, while also providing an installation position for the mounting plate; by adding a metal support base to the bottom of the mold to increase the rigidity of a conventional resin mold, deformation of the resin mold body during drying, movement, etc., can be prevented, avoiding deformation of the carbon fiber sample caused by mold deformation, thus ensuring stable mold support for the carbon fiber sample.

The application provides a hollow S-1 encapsulated Ni particle catalyst for catalyzing maleic anhydride hydrogenation to prepare succinic anhydride and a preparation method thereof. The hollow S-1 encapsulated Ni particle catalyst is prepared by using a template agent, a silicon source and water as raw materials to prepare Silicalite-1 molecular sieve (S-1 molecular sieve), hydrothermally modifying the S-1 molecular sieve with an alkali solution to form S-1 molecular sieve with a hollow structure (HoS-1 molecular sieve), loading a Ni source on the HoS-1 molecular sieve carrier through an impregnation method, and then drying, calcining and reducing to obtain the hollow S-1 encapsulated Ni particle catalyst. Compared with the prior art, the hollow S-1 encapsulated Ni particle catalyst for catalyzing maleic anhydride hydrogenation to prepare succinic anhydride has the advantages of short preparation process period, low cost, mild hydrogenation reaction condition, effective prevention of active Ni particle shedding due to the hollow outer wall, and excellent catalytic activity and stability.

The application provides a water-phase high-brightness fluorescent quantum dot and a preparation method thereof. 0.07 -Cu 0.03 In 0.1 Se 0.14 Compared with the prior art, the water-phase high-brightness fluorescent quantum dot has high-brightness fluorescent performance, the fluorescent intensity is more than 800, the absolute value of Zeta potential is greater than or equal to 56 mV, the system stability is good, the water-phase high-brightness fluorescent quantum dot can be mutually soluble with water, the interface with oil is clear, the hydrophilicity is high, and the water-phase high-brightness fluorescent quantum dot can be applied to gene detection, medical diagnosis, biological imaging, targeted drug delivery and the like. The preparation method adopts a solvothermal technology, the preparation method is simple and the preparation period is short, and the water-phase high-brightness fluorescent quantum dot obtained by using the preparation method also has the characteristics of non-toxicity, easy operation, high sensitivity and excellent stability.

The invention discloses aerogel slurry as well as a production method and application thereof. The production method comprises the following steps: firstly, preparing aerogel microsphere particles, silicon microsphere ink particles and polymer slurry step by step, and mixing the aerogel microsphere particles and the silicon microsphere ink particles with the polymer slurry to prepare the aerogel slurry. The prepared aerogel slurry is coated with multiple layers of aerogel slurry in the modes of brush coating, roll coating, spray coating and the like, and the aerogel coating is prepared. The preparation method of the aerogel slurry is scientific and reasonable in process, simple and convenient to operate and short in preparation period, meanwhile, only water is used as a solvent in the preparation process of the aerogel slurry, no organic solvent is used in the whole process, the cost is low, the aerogel slurry is green and safe, and a product is stable in structure, uniform in internal structure, lighter and more environmentally friendly.

The invention discloses a desulfurizing agent for acidizing a sulfur-containing reservoir, which is prepared from the following components in percentage by volume: 20 to 30 percent of compound complex iron reagent, 15 to 20 percent of amine reagent, 5 to 15 percent of activating agent and 35 to 60 percent of solvent water, and the sum of the volume contents of the components is 100 percent. The desulfurizing agent for acidification of the sulfur-containing reservoir solves the problems that in the prior art, the compatibility of a desulfurizing agent and other reagents in the acidification process is poor, and the acting effect is affected. The invention further discloses a preparation method of the desulfurizing agent for acidification of the sulfur-containing reservoir.

This invention relates to the field of vanadium alloy metallurgical technology, and discloses a vanadium alloy slag-blocking device and its preparation method, comprising: uniformly setting tie bars circumferentially on the inner wall of a ring-shaped rigid structure; preparing a binding layer material, mixing it evenly and filling it into the inner side of the rigid structure, and compacting it by vibration with a vibration device to ensure that the binding material completely wraps the tie bars and adheres to the inner side of the rigid structure; after the binding layer is naturally air-dried to remove water, it is baked multiple times to obtain the vanadium alloy slag-blocking device; wherein, by weight, the binding layer comprises 65-85 parts of corundum slag with different particle sizes, 10-15 parts of coagulant, 10-15 parts of cementitious material, and 5-15 parts of water. This invention also provides this device and its application. This invention utilizes solid waste generated from vanadium ferrometallurgy to prepare a slag-blocking device, reducing raw material costs, improving preparation efficiency, achieving environmentally friendly production, and extending the service life of the slag-blocking device, ensuring efficient and stable operation of vanadium ferrometallurgy.

The application discloses a kind of transmission type three-layer composite structure fluorescent ceramic for laser illumination and a preparation method thereof, and the fluorescent ceramic is three-layer composite structure from top to bottom in turn (Re 1‑x Ce x )3Al5O 12 Yellow-green fluorescent layer, transparent high-thermal-conductivity heat-dissipation layer, (A 1‑y Ce y )3(Al 1‑z B z )5O 12 Red fluorescent layer. The preparation method comprises the following steps: placing yellow-green fluorescent ceramic obtained by dry pressing into the bottom of a copper mold, pouring magnesium-aluminum spinel molten liquid into the preheated copper mold, placing red fluorescent ceramic above the molten liquid, and placing the composite structure material obtained after cooling in a muffle furnace for crystallization treatment to obtain the composite structure fluorescent ceramic of yellow-green fluorescent layer / transparent high-thermal-conductivity heat-dissipation layer / red fluorescent layer. The method can realize good connection and combination between different ceramic matrices, and has the advantages of simple process and low cost. The obtained transmission type composite structure fluorescent ceramic can maintain higher luminous intensity at high temperature, and excellent color rendering property can be obtained.

The application relates to a device and a method for preparing a fluorine-based glass optical fiber preform rod cladding hollow tube. In the device, by reducing the air pressure in a closed crucible environment and assisting with a constant rotation rate, dissolved gas in the glass liquid can be effectively removed, and a fluorine-based glass preform rod cladding hollow tube without bubbles, high uniformity and high interface quality can be automatically / semi-automatically prepared. The method has a short preparation period and is expected to be applied to the preparation of a fluorine-based optical fiber preform rod with a high-quality core-cladding structure.

This invention discloses a combined electro-discharge machining (EDM) method for long, narrow slit structures, specifically relating to the field of EDM technology. The steps are as follows: The workpiece is mounted on the EDM electrode wire; the EDM electrode wire moves in the XY plane; the machined workpiece is then aligned with the electrolytic machining wire electrode; the power supply and electrolytic control system are turned on for secondary machining; the electrolytic machining wire electrode moves along a predetermined trajectory in the XY plane; after secondary machining, the power supply is disconnected, the electrolyte circulation system is shut off, the electrolytic machining wire electrode and workpiece are removed, and both are cleaned, thus completing the machining process. This invention solves the problem of existing machining methods struggling to achieve high-quality machining of ultra-thin sheet-like long, narrow slit structures, improving the machining quality and efficiency of such structures.

The application provides a pyridine imine nickel complex as shown in formula (I), wherein R 1 , R 2 , R 3 , R 4 and X are as defined in the description. The nickel complex has the advantages of high catalytic activity, simple preparation method, low cost, stable performance and the like, the prepared polyethylene has a weight average molecular weight Mw of 2.50-9.59 kg·mol ‑1 -1, a narrow molecular weight distribution of 2.01-3.43, high branching degree, adjustable double bond content and great industrial application value.

The invention discloses boron nitride coated high-strength elastic ceramic nanowire aerogel as well as a preparation method and application thereof, and belongs to the technical field of superelastic inorganic material preparation. Comprising the following steps: taking silicon carbide nanowire aerogel or silicon nitride nanowire aerogel as a framework, uniformly coating boron nitride on the surface of the framework by adopting a chemical vapor deposition method, and forming fixed boron nitride nodes between adjacent or contacted silicon carbide or silicon nitride nanowires. The strength of the prepared ceramic nanowire aerogel can reach 787.0 kPa, and the ceramic nanowire aerogel has good recovery capacity under the compression strain of 80% and is expected to be used as materials for high-temperature heat prevention and insulation, high-performance damping, heat sealing and the like in an extreme environment.

The application belongs to the technical field of composite phase change materials, and particularly relates to a preparation method of a corn cob / steel slag binary solid waste composite phase change energy storage material, which comprises the following steps: taking corn cob and steel slag as base matrix raw materials, performing carbonization treatment on the corn cob to construct a porous network cross-linked carbon matrix, performing high-temperature calcination treatment on the steel slag to reconstruct crystals, and mixing and co-sintering to form a binary solid waste framework. A phase change material is loaded into the binary solid waste framework through an immersion adsorption method, and finally the corn cob / steel slag binary solid waste composite phase change energy storage material is obtained. The application realizes resource utilization of solid wastes which are widely sourced and low in cost. The porous structure has adsorption performance and heat conduction performance. The solid waste composite phase change energy storage material prepared by the application has excellent heat storage performance and good stability and is not prone to leakage, and has a wide application prospect.

This invention provides a two-dimensional triangular lattice rare-earth-based titanate polycrystalline material, its preparation method, and its applications. The chemical formula of the rare-earth-based titanate polycrystalline material is Ba6M2Ti4O. 17 The space group is P63 / mmc, where M is one or more of Nd, Gd, and Yb. The novel two-dimensional triangular lattice rare-earth-based titanate polycrystalline material provided by this invention has a compact structure, a simple preparation process, and its frustrated structure of localized electron spins significantly reduces the minimum cooling temperature to the tens of millikons. Furthermore, it exhibits high magnetic ion density and large cooling capacity, making it an excellent magnetic refrigerant.

The invention relates to the technical field of lithium ion batteries, and particularly discloses carbon-coated lithium iron phosphate and a preparation method thereof. Comprising the following steps: taking Prussian blue as a carbon source and an iron source, mixing a lithium source, a phosphorus source, Prussian blue and a dispersing agent in water, and performing ball milling to obtain a precursor; and calcining the precursor in a protective atmosphere to obtain the carbon-coated lithium iron phosphate. Prussian blue is used as an iron source and a carbon source at the same time, secondary sintering or additional carbon source adding is not needed, one-time sintering forming is achieved, the process is simple, and operation is easy. The carbon-coated lithium iron phosphate provided by the invention has excellent rate capability and long cycle performance, and can meet the requirements of high energy and high power output.

The invention discloses a spiro [naphthalene-1, 5 '-pyrrolo [1, 2-a] quinoline]-ketone derivative as well as a synthesis method and application thereof, and relates to the technical field of organic synthesis, and the structural formula of the spiro [naphthalene-1, 5'-pyrrolo [1, 2-a] quinoline]-ketone derivative is shown as the following formula I. The invention synthesizes a novel spiro skeleton compound capable of inhibiting the activity of tumor cells. According to the preparation method of the spiro skeleton compound, the structure of an initial compound is simple, raw materials are easy to obtain, reaction conditions are mild, operation is easy, the preparation period is short, and the yield is high; the spirocyclic skeleton compound has a remarkable inhibition effect on tumor cells, can be used for preparing antitumor drugs, lays a foundation for synthesis and application of the spirocyclic skeleton compound and provides a new thought.

The present disclosure relates to a preparation method of a nano-porous doped bismuth vanadate and a photoactive electrode, and relates to the technical field of doped bismuth vanadate preparation. The method comprises: 1. obtaining a first solution: obtaining a first citric acid solution, adding a bismuth source, a lanthanum source and a molybdenum source to obtain the first solution; the amount of substance of citric acid is N, and the amounts of substance of bismuth element, lanthanum element and molybdenum element are x, y and z respectively, so that N:(x+y+z)=(1.5-4):1; obtaining a second solution: obtaining a second citric acid solution and adding a vanadium source to obtain the second solution; the amount of substance of vanadium element is A, so that x:y:z:A=(6-9):(0.5-2):(0.5-2):10, and x+y+z=A; 2. adding the second solution to the first solution in batches to obtain a third solution; 3. adjusting the pH value of the third solution to 4-8 and drying; calcining the dried product to obtain the nano-porous doped bismuth vanadate.

The application discloses a high-entropy rare earth silicate ceramic powder and a preparation method and application thereof. The preparation method of the high-entropy rare earth silicate ceramic powder comprises the following steps: 1) mixing rare earth oxide powder, SiO2 powder, LiCl and KCl and grinding to obtain a mixed powder; and 2) calcining the mixed powder under the condition that the temperature is 700 DEG C to 900 DEG C, and then performing water washing and drying to obtain the high-entropy rare earth silicate ceramic powder. The high-entropy rare earth silicate ceramic powder has the excellent characteristics of high purity, small particle size, uniform element distribution and large component space, and the preparation method has the advantages of short preparation period, low synthesis temperature, small energy consumption and high efficiency, is suitable for being used on a hot end part of an aerospace engine and has a very wide application prospect.

This invention relates to the field of breathable ring technology, providing a carbon / carbon composite breathable ring, its preparation method, and its applications. The invention involves sequentially impregnating, curing, carbonizing, and graphitizing a carbon fiber breathable ring preform to obtain a graphitized breathable ring blank. The graphitized breathable ring blank is then refined, purified, and heat-treated to obtain the carbon / carbon composite breathable ring. This invention combines impregnation and carbonization processes with high-temperature purification processes to prepare a high-density, high-permeability carbon / carbon composite breathable ring, which better meets the requirements of photovoltaic thermal fields. Furthermore, it exhibits higher thermal mechanical properties, longer service life, and lower energy consumption, reducing production costs and meeting the growing demand for photovoltaic thermal field accessories. Moreover, the breathable ring prepared by this invention has high purity, and the process is simple, convenient, has a short preparation cycle, and low production cost, making it suitable for large-scale industrial production.

The invention discloses an assembly table for manufacturing a railway vehicle bottom door frame assembly. According to the assembling table, the middle supporting assembly, the supporting check block, the first clamp, the supporting block, the two baffles and the multiple second clamps are matched with one another, supporting, positioning and rigid fastening are conducted on all components of the bottom door frame assembly, the assembling precision of the bottom door frame assembly is guaranteed, and the structure is simple.