227results about How to "High bulk density" patented technology

The invention relates to a method for preparing a lithium iron phosphate / carbon composite material of a lithium ion battery, which belongs to the technical field of lithium ion batteries. The method for preparing the lithium iron phosphate / carbon composite material of the lithium ion battery comprises the following steps of: 1) preparing a suspending graphene-dispersed aqueous solution system, namely, crushing graphite to 1 to 5 microns, adding the crushed graphite into distilled water or purified water, adding 0.1 to 5 percent of surfactant, heating with stirring the mixed solution to 180 to 250 DEG C in a sealing way, performing stirring for 2 to 6 hours and reducing the temperature; 2) crushing lithium iron phosphate to the particle size of 1 to 5 microns, adding the crushed lithium iron phosphate into the distilled water or the purified water, adding with stirring 0.01 to 1 percent of coupling agent, performing uniform stirring, adding the graphene-dispersed aqueous solution, and performing stirring and filtration; and 3) vacuum-drying solid powder obtained by the filtration, and calcinating the dried solid powder for 2 to 12 hours to obtain the graphene-coated lithium iron phosphate cathode material. The method has the advantages of simple process, high material performance, high conductivity, high bulk density, high compacted density and the like.

The invention provides a preparation method of an isotropic Ti2AlNb / TiAl-based interpenetrating composite material, and belongs to the technical field of intermetallic compound-based composite materials. The method comprises the following steps: firstly, designing a Ti2AlNb reinforcement framework of various TPMS configurations by utilizing implicit function modeling; then, carrying out anisotropy research on the TPMS configuration by utilizing finite element simulation; secondly, a Ti2AlNb reinforcement framework of a TPMS configuration is prepared through a selective laser melting (SLM) technology; and finally, the TPMS configuration Ti2AlNb / TiAl-based interpenetrating composite material is prepared through vacuum hot pressing sintering of HPS. Therefore, strong anisotropy of a traditional fiber reinforced composite material in mechanical property is avoided, good matching of strength, plasticity and toughness of the composite material is achieved, and a new thought and a new solution are provided for breaking through the application bottleneck of TiAl in spaceflight power system hot end components.

The invention discloses a water-based lithium battery positive electrode adhesive, a preparation method and application. The adhesive is of a single-layer or multi-layer shell core-shell structure formed by polar monomers such as acrylic acid, acrylate monomers, cross-linking monomers, self-emulsifying monomers and water through core-shell emulsion polymerization; by controlling the mass percent of acrylate monomers, polar groups and the like in the core layer structure and the shell layer structure and selecting proper types and dosages of cross-linking monomers and self-emulsifying monomers, the adhesive has proper surface tension, shows excellent adhesion and wettability to the current collector, has high peel strength, and is suitable for the current collector. According to the present invention, the lithium ion battery pole piece has the low glass-transition temperature so as to ensure the high toughness, the high surface density, the excellent electrolyte resistance, the excellent electrical property, the excellent coating property and the like of the pole piece, and the raw materials are all non-fluorine materials so as not to produce hydrogen fluoride and other harmful gases during the lithium battery recovery; water is used as a solvent, recycling is not needed, environment friendliness and low carbon are achieved, the manufacturing process is simplified, and the application range is widened.

The preparation method comprises the following steps: mixing polysaccharide gum with water, carrying out wet ultrafine grinding to obtain an ultrafine polysaccharide gum aqueous solution, and uniformly infiltrating the polysaccharide gum into cellulose or derivatives thereof by adopting high-shear mixing to form micelles; and promoting the micelles to form a honeycomb structure through microwave vacuum drying, and finally spraying ultrapure water atomized by high pressure to the honeycomb micelles and drying to obtain the hydrogel for absorbing grease. The water absorption capacity of the prepared hydrogel reaches 100 times or above, the storage modulus is 1350 Pa or above, grease can be efficiently absorbed, and the hydrogel has wide development prospects in the field of weight-reducing medicine or food.

The invention relates to the technical field of high-temperature alloy powder metallurgy, in particular to a preparation method of a high-strength cellular distribution gamma'phase high-temperature alloy, which comprises the following steps: preparing high-temperature alloy powder; the prepared high-temperature alloy powder is loaded into a first sheath, and the first sheath is vacuumized and sealed; carrying out preheating treatment on the first sheath; the high-temperature alloy powder in the first package sleeve is dispersed; opening the first sheath, and transferring the high-temperature alloy powder from the first sheath into a second sheath through a charging bucket under a vacuum condition; performing hot isostatic pressing treatment on the second sheath filled with the powder to obtain a first workpiece; cooling the first workpiece to obtain a second workpiece; removing a second sheath outside the second workpiece to obtain a blank, and performing heat treatment on the blank to obtain a target alloy; the powder metallurgy technology is utilized, the preparation technology is adjusted, a specially-distributed gamma'phase is formed in the alloy, and therefore the tensile strength and the endurance strength of the alloy are improved.

The invention discloses binder spraying 3D printing equipment and a printing method for low-fluidity powder, and relates to the technical field of 3D printing. The printing method comprises the steps that the powder forming module is controlled to reach an initial position; the powder forming module comprises a powder falling module and a powder spreading module which move synchronously; powder is added into the powder falling module through the powder supplementing module; the powder forming module is moved to the initial powder laying position, and powder is controlled to be scattered on a vibration plate from a powder supplementing bearing plate of the powder falling module; vibration of a vibration plate is controlled, so that the powder is transferred to the front of the powder spreading module and is spread and compacted; laying of single-layer powder is completed; the steps are repeated to complete laying of the bottom powder layer; and laying of the slice layers is completed repeatedly on the bottom powder layer, the ink jetting module is controlled to move along with the powder forming module, a binder is jetted to each slice layer, and a 3D printing product is obtained through curing. A matching scheme of layer-by-layer powder supply, independent powder spreading and independent compaction is adopted, so that high density and high uniformity of a low-fluidity powder printing breadth are ensured.

The invention discloses a preparation method of electrode slurry for an electrostatic chuck, and belongs to the technical field of electrostatic chucks, powder is dispersed in an organic solvent through a ball mill, the powder is aluminum oxide powder and two or more kinds of carbide powder with different particle sizes, the D50 particle size of the aluminum oxide powder is 3-6 [mu] m, and the D50 particle size of the carbide powder is 3-6 [mu] m; powder with different particle sizes can have higher stacking density, few organic solvents are needed in the dispersion process, shrinkage after sintering is small, and cracking and layering of electrode slurry are not prone to being caused; ball-milling and dispersing the powder, drying in a drying oven for 24 hours, grinding by using a mortar, and sieving for later use; and mixing the sieved powder with an organic carrier with the solid content of 60-80%, mixing for 30-60 minutes in a mixing and kneading machine, and then rolling in a three-roller machine to obtain the required electrode slurry. According to the invention, three kinds of particles with different particle sizes are mixed, so that the powder bulk density is greatly improved, the electrode thickness controllability is improved, and the shrinkage ratio after burning is reduced.

The invention belongs to the technical field of CPVC pipe preparation, and provides a high-strength toughened CPVC pipe and a preparation method thereof. Firstly, butadiene and divinyl benzene are copolymerized to form a high-crosslinking structure, rigid support is provided, butyl methacrylate and acrylonitrile are copolymerized, flexibility and polarity are adjusted, interface bonding force is enhanced, and acrylic acid, epoxy acrylate and ethyl methacrylate are copolymerized to optimize compatibility with a matrix; secondly, through copolymerization of monomers such as 2-sulfonic acid ethyl methacrylate, polyethylene glycol methacrylate and dimethylacryloyloxyphosphonic acid, the polarity and flexibility of the compatilizer are adjusted, and the interface bonding strength of the compatilizer to a CPVC matrix and a modified elastomer is improved, so that the mechanical property of the composite material is remarkably improved; finally, nano SiO2 is subjected to surface modification through a silane coupling agent, so that the dispersity of the inorganic filler and the binding force with a matrix are improved, and the rigidity and the thermal stability of the composite material are enhanced.

The invention discloses a multi-scale hybrid particle reinforced aluminum-based composite material, which is prepared from the following raw material powder in percentage by mass: 70 to 98.5 percent of AlSi10Mg atomized powder, 0.5 to 20 percent of micron-sized Al2O3 powder, 0.5 to 20 percent of nano-sized Al2O3 powder and 0.5 to 20 percent of submicron-sized SiC powder, and the sum of the mass percent of the components is 100 percent. The material is an aluminum-based composite material with high strength, high toughness and high hardness. The invention further provides an SLM preparation method of the multi-scale hybrid particle reinforced aluminum-based composite material, through particle content optimization, powder preparation process innovation and SLM process parameter optimization, the high-strength, high-toughness and high-hardness aluminum-based composite material is obtained, and additive manufacturing of the aluminum-based composite material is achieved.

The present application discloses a method for preparing a carbon material for a battery, comprising: filtering and concentrating papermaking black liquor to obtain liquid lignin; polymerization: adding a cross-linking agent to the liquid lignin for cross-linking and curing reaction to obtain a lignin polymer solid; pre-oxidation: pre-oxidizing the lignin polymer solid to obtain a lignin-based resin; pre-carbonization: pre-carbonizing the lignin-based resin in a non-oxidizing gas atmosphere to obtain a carbon material precursor 1; gas phase deashing: gas phase deashing the carbon material precursor 1 in a non-oxidizing gas atmosphere under the action of a halogen compound and / or a halogen element to obtain a carbon material precursor 2; calcination: crushing the carbon material precursor 2 and calcining it in a protective atmosphere to obtain a carbon material for a battery. The method of the present application effectively improves the expansion and foaming phenomenon during lignin carbonization, and the obtained carbon material has low ash content, controllable specific surface area, and excellent electrochemical performance. A lignin-based resin as mentioned above is also disclosed.

The invention discloses a method for preparing titanium-aluminum alloy powder based on a plasma rotating electrode atomization method, and relates to a preparation method of titanium-aluminum alloy powder. The method aims at solving the technical problems that titanium-aluminum alloy powder prepared through an existing method is uneven in particle size, poor in sphericity degree and high in oxygen content, and comprises the steps that firstly, metal raw materials are weighed according to the target titanium-aluminum alloy chemical component proportion, and a uniform cast ingot is obtained through smelting of a vacuum arc smelting furnace; processing the cast ingot into an electrode bar with a smooth surface, mounting the electrode bar on plasma rotating electrode atomization equipment, enabling the electrode bar to rotate at a high speed, melting alloy at the end part of the electrode bar by utilizing a plasma beam generated by a plasma generator, atomizing the alloy into liquid drops under the action of centrifugal force, and cooling and solidifying the liquid drops in a high-purity argon protection atmosphere to form powder; and finally, the powder is collected and screened, finished powder is obtained, the sphericity degree of the powder reaches 95% or above, the oxygen content is lower than 500 ppm, particle size distribution is uniform, and the powder can be used in the fields of aerospace, the automobile industry, energy and the like.

The invention belongs to the field of organic electroluminescence, and discloses an organic electroluminescence material as well as a preparation method and application thereof. The structure of the organic electroluminescent material is as shown in a chemical formula I: # imgabs0 #. According to the organic electroluminescent material compound provided by the invention, an aryl-substituted dibenzofuran group and a triarylamine group are bridged through a naphthylene group to form a mother nucleus main body, the rigid dibenzofuran structure can effectively enhance the structural stability, and the existence of the triarylamine group can improve the hole transport efficiency of the material; furthermore, the naphthylene group is bridged between the two main body structures, so that a more efficient conjugated system can be formed, the electron mobility of the whole material is improved, and the device has high luminous efficiency and long service life, and can maintain lower driving voltage at the same time.

The invention discloses a catalyst, a preparation method and application of the catalyst in preparation of polyethylene and chlorinated polyethylene. The catalyst carrier is synthesized under a low-temperature mild condition, the catalyst has high polymerization activity, strong hydrogen regulation sensitivity and good copolymerization performance, and the ethylene polymer with narrow particle size distribution of polymerization powder, high bulk density and excellent fluidity is obtained.

The invention provides zirconium oxide ceramic slurry and a preparation method thereof, a zirconium oxide ceramic product and a production method thereof. The zirconium oxide ceramic slurry comprises zirconium oxide powder and a resin component, the resin component comprises photosensitive resin, a photoinitiator, a linear polymer and a thermal initiator, and the preparation method comprises the following steps: mixing the photosensitive resin, the photoinitiator and the linear polymer for the first time to obtain a first resin liquid; sequentially carrying out stirring and second ball milling on the second mixed zirconium oxide powder and the first resin liquid to obtain first slurry, then adding a thermal initiator, and carrying out third ball milling to obtain second slurry; the second slurry is subjected to defoaming treatment, and the zirconia ceramic slurry is obtained. The density of the biscuit can be improved, then the sintering resistance of the product in the final sintering process is reduced, and the final sintering density and the mechanical property of the final product are improved.

The invention discloses active magnesium oxide and a preparation method thereof, and relates to the technical field of magnesium oxide preparation. The method comprises the following steps that first magnesium ore is subjected to calcination dissociation, enhanced leaching and carbonization separation, and then calcium carbonate and an active low-calcium magnesium-rich solution are obtained; carrying out calcining dissociation and mechanical fine grinding on the second magnesium ore to obtain a fine material, or directly carrying out mechanical fine grinding on the second magnesium ore to obtain the fine material; the active low-calcium magnesium-rich liquid is pumped into a hydration activation tank, stirring is started, then the fine material is conveyed to the hydration activation tank, the active low-calcium magnesium-rich liquid and the fine material are subjected to a hydration reaction, and composite magnesium salt is formed; and drying and scattering the composite magnesium salt, conveying to a calcining furnace, calcining, cooling and spirally discharging to obtain the active magnesium oxide. The magnesium oxide prepared by the method is moderate in density, rich in active sites and good in dispersity, has excellent adsorption, hydration and ionization properties, has remarkable effect and cost advantages as an alkaline precipitator, and is beneficial to market popularization and application of high-activity magnesium oxide products in the fields of environmental protection and metallurgy.

The invention discloses a lithium ion battery silicon-carbon negative electrode composite powder material and a preparation method and a production device.The preparation method of the lithium ion battery silicon-carbon negative electrode composite powder material comprises the following steps that under the vacuum state, inert gas (nitrogen or argon) is introduced for protection, matrix powder is made to be in a fluidized state and heated, and the matrix powder is cooled to the room temperature to obtain the lithium ion battery silicon-carbon negative electrode composite powder material. Silicon source gas or carbon source gas is introduced, the heating temperature is higher than the cracking temperature of the silicon source gas or the carbon source gas, and after the silicon source gas or the carbon source gas is cracked, the surface of the matrix powder is coated with silicon or carbon; when the matrix powder is carbon powder, the introduced gas is silicon source gas; when the matrix powder is silicon powder, the introduced gas is carbon source gas. The nanoscale silicon-carbon negative electrode composite powder material prepared by the invention has the advantages of regular powder shape, high purity, strong interface bonding force between a surface coating material and basic powder, good coating consistency and low energy consumption.

The invention relates to a high-temperature refractory brick taking low-grade magnesite tailings as aggregate, which is characterized by comprising the following components in percentage by weight: 60-65wt% of low-grade magnesite tailings; 15 to 25 weight percent of bentonite; 5-10 wt% of magnesium oxide; 1-3 wt% of magnesium chloride; 5.5 to 10 wt% of a modifier; and 4-6 wt% of a binding agent. The high-temperature refractory brick blank has the beneficial effects that the low-grade magnesite tailings which are relatively high in SiO2 content and cannot be used for preparing magnesium materials are used as main materials, and a certain amount of bentonite is added to serve as aggregate, so that the high-temperature refractory brick blank is complete in binding phase, small in apparent porosity and about 14-15%, high in load deformation temperature and about 1700-1720 DEG C, and high in strength and toughness; the prepared magnesite tailings have excellent chemical mineral structures, physical properties and thermal shock resistance, so that mineral resources are saved, the problem of discharge of the magnesite tailings after mineral separation is solved, and the magnesite tailings are energy-saving and environment-friendly.

The invention discloses a cable-stayed bridge girder symmetric suspended pouring efficient construction method based on a front fulcrum cable-stayed hanging basket, which adopts a front fulcrum hanging basket symmetric suspended pouring mode for construction, and comprises the following steps: A, mounting a hanging basket; b, mounting a bottom film; c, mounting and tensioning the stay cable; d, mounting reinforcing steel bars and prestressed pipelines; e, end film installation; f, concrete pouring; g, pre-stress construction in the beam body; h, the hanging basket is placed downwards, then walking anchoring is conducted on the hanging basket, and the formwork is lifted and installed; the hanging basket is installed in a hoisting mode after being assembled, and a corresponding assembling place is selected according to the position of a pier; the concrete used during concrete pouring is good in flowability, workability, water-retaining property, cohesiveness and volume weight, and the concrete is uniformly put into a mold and is vibrated and compacted during concrete pouring; during prestress tensioning, multiple times of tensioning circulation are conducted; a deviation rectifying mechanism is arranged on the rear portion of the hanging basket. The problems that an existing hanging basket is prone to deviation due to errors and stability in erection, uneven concrete pouring and prestress loss are solved.

The invention discloses aluminum oxide ceramic granulation powder and a preparation method thereof and high-density aluminum oxide ceramic, and the method comprises the following steps: weighing required raw materials for later use according to the mass percentage: 75% of aluminum oxide raw powder and the balance of pure water; aluminum oxide grinding balls are put into a ball-milling tank, the weighed aluminum oxide raw powder and pure water are put into the ball-milling tank in the sequence of water first and powder second for ball-milling, the ball-milling time is 3 h, and the rotating speed of the ball-milling tank is 35 Hz; sieving a mixture of the grinding balls and the slurry in the ball-milling tank by using a screen to separate the grinding balls and the slurry; pouring the sieved slurry into a stirring kettle for stirring, sequentially adding a dispersing agent, a binder, a plasticizer and a lubricant in stages in the stirring process, and adjusting the pH value of the slurry to obtain aluminum oxide slurry; and carrying out spray granulation on the aluminum oxide slurry by using a spray granulator to obtain the aluminum oxide ceramic granulation powder. The alumina ceramic granulation powder prepared by the invention is relatively high in apparent density and good in fluidity, and the alumina ceramic sintered by the alumina ceramic granulation powder is relatively high in density.

The invention discloses an anti-erosion and anti-permeation yttrium oxide refractory material as well as a preparation method and application thereof. According to the method, a small amount of sintering aid powder is doped into YO powder to reduce the sintering temperature, and meanwhile, the granularity of the powder, cold isostatic pressing parameters and a sintering process are regulated and controlled to prepare the YO refractory material which is high in density and large in grain size and does not generate a second phase. The method disclosed by the invention is suitable for preparing the powder for the Y2O3 crucible and the cold isostatic pressing formed Y2O3 crucible, and the erosion and infiltration resistance of the crucible to the titanium-aluminum alloy melt can be effectively improved.

The invention discloses a cement-free high-chromium castable and a preparation method thereof, chromium oxide frits or chromium-aluminum solid solution particles, chromium oxide fine powder and alumina micro powder are used as main raw materials, zirconium oxide micro powder, magnesium oxide fine powder, silicon oxide micro powder and the like are added, and the cement-free high-chromium castable is prepared through vibration molding. The process is simple, traditional aluminate cement is not used as a binding agent, the porosity of the prepared cement-free high-chromium castable is reduced, the volume density, the compression strength and the breaking strength are improved, and due to the fact that spinel is generated in the use process of the castable and the castable does not contain calcium oxide, the cement-free high-chromium castable has the advantages of being environmentally friendly and low in cost. The thermal shock resistance and the slag corrosion resistance of the high-chromium castable are obviously improved.

The invention discloses a granulation method and system for improving the bulk density of synthesized high-purity quartz sand, and the method comprises the following steps: carrying out spraying treatment on silica sol to form silica sol liquid drops, and meanwhile, carrying out microwave drying on the silica sol liquid drops to uniformly heat the inside and outside of the silica sol liquid drops to obtain preliminarily dried gel particles; and putting the gel particles into drying equipment for drying treatment to obtain a granulated product. The hollow rate of the granulated product can be greatly reduced, so that the stacking density of the synthesized high-purity quartz sand product is improved, a solid particle product with few defects is prepared, the number of bubbles in a downstream product is effectively reduced, and meanwhile, the bubble size in the downstream product can be effectively reduced.

The preparation method comprises the following steps that S1, a silver nitrate solution and a reducing agent solution are added into a compound dispersing agent solution at the same time, stirring reaction is conducted, and a nanometer silver powder suspension is obtained; s2, adding a flocculant solution into the nano silver powder suspension, and stirring for reaction to obtain a reaction solution; and S3, carrying out solid-liquid separation on the reaction liquid to obtain a solid component, and then drying and crushing to obtain the nano silver powder for the low-temperature sintering type water-based polyester-based conductive paste. The mass ratio of the silver nitrate to the reducing agent to the compound dispersing agent to the flocculating agent is (1000-1500): (500-1000): (20-60): (3-8); according to the preparation method, the mixed dispersing agent, the silver nitrate solution, the reducing agent solution and the flocculating agent react to obtain the nano silver powder which is good in dispersity, high in yield, smooth in surface, small in particle size and high in apparent density and tap density, and preparation of the low-temperature sintering type waterborne polyester-based conductive paste is facilitated.

The invention provides a copper-based adsorbent and application thereof in a glove box purification column, and belongs to the technical field of catalysts containing metals or metal oxides. The method comprises the following steps: adding active metal salt into a solvent, mixing and dissolving to obtain a mixed metal salt solution, mixing and dissolving a precipitant and the solvent to obtain a precipitant solution, co-precipitating the mixed metal salt solution and the precipitant solution, and separating, drying and calcining the obtained precipitate to obtain the supported copper-based adsorbent with the size phi of 1.8-6 mm. The copper-based adsorbent provided by the invention has good oxygen removal performance and regeneration capacity, can be continuously produced and is short in reaction time.

The invention belongs to the technical field of medicine refining, and relates to a cepharanthine crystal and a preparation method thereof. Compared with amorphous cepharanthine powder, the crystal provided by the invention is high in stacking density, good in fluidity, high in stability and convenient to store and transport. The cepharanthine crystal form I crystal and the five cepharanthine solvate crystals provided by the invention have better stability, a sample is placed in a dynamic steam adsorption instrument at 40 DEG C, the weight when the mass change is less than 0.01 g within 3 hours is recorded, the hygroscopicity of the cepharanthine crystal form I crystal and the five cepharanthine solvate crystals is far lower than that of amorphous cepharanthine powder, and the stability of the cepharanthine crystal form I crystal and the five cepharanthine solvate crystals is greatly improved. Therefore, compared with amorphous cepharanthine powder, the stability of the cepharanthine crystal provided by the invention is greatly improved.

The invention provides a gamma-cyclodextrin crystal form A and a preparation method thereof, an X-ray powder diffraction pattern of the gamma-cyclodextrin crystal form A has characteristic peaks when a 2 theta value is 9.15 + / -0.2 degrees, 12.04 + / -0.2 degrees and 16.35 + / -0.2 degrees, and the preparation method comprises the following steps: adding a certain amount of gamma-cyclodextrin into a certain amount of water, stirring, and carrying out ultrasonic dispersion to obtain a gamma-cyclodextrin crystal form A; the preparation method comprises the following steps: covering a bottle with a cover, heating in a biochemical incubator, dissolving, filtering a dissolved clear solution into a nuclear magnetic tube, adding a certain amount of hydroxypropyl methyl cellulose, vacuumizing, introducing nitrogen, fastening a rubber plug, heating in the biochemical incubator, setting heating and cooling procedures of the biochemical incubator, crystallizing, separating out white cluster-shaped solids at the bottom of the bottle, and drying, thereby obtaining the white cluster-shaped solid. And separating out a solid to obtain the gamma-cyclodextrin crystal form A. The crystal form A is low in energy, more stable, higher in stacking density and convenient to package, transport and store.

The utility model provides a kind of seed dressing device before peanut sowing, belong to peanut sowing technical field. Including seed dressing jar body, the periphery of seed dressing jar body is fixed with fixed frame, and the upper side of seed dressing jar body is provided with feed inlet, the side of fixed frame is fixed with extension frame, and the inside and outside of extension frame upper side and seed dressing jar body are jointly installed with even sprinkling irrigation mechanism. The utility model is by being provided with even sprinkling irrigation mechanism, personnel can pour peanut seed from feed inlet into seed dressing jar body in advance during operation, then personnel will need to mix seed dressing agent with a variety of raw materials and other liquids etc. in turn from feeding pipe into mixing cylinder, then start first motor to make first driving rod with periphery staggered distribution set of stirring rod to mix the above-mentioned variety of materials, after mixing and stirring are finished, personnel can start conveying pump body, and can be conveyed to sprinkling irrigation ring pipe frame and be sprayed by thus inside ring distribution set of sprinkling irrigation head under the guidance of first pipeline, second pipeline etc. component with seed dressing agent.

The invention relates to the technical field of preparation of a battery positive electrode material, in particular to a method for modifying a battery carbon-sulfur positive electrode material by using defect-free original graphene, which comprises primary coating, secondary coating and post-treatment. According to the method, defect-free original graphene coating modification is carried out on a carbon-sulfur positive electrode material of a liquid / solid lithium-sulfur battery, and ion intercalation lattice induced blocking of sulfur is completed through a nanocarbon secondary coating technology. Compared with the existing sulfur / sulfur-carbon positive electrode material, the specific capacity of the graphene sulfur-carbon positive electrode material prepared by the method disclosed by the invention is greatly increased and is close to a theoretical value, and the electrical conductivity and the heat-conducting property are greatly improved. The weight energy density and the volume density of the liquid / solid lithium-sulfur battery prepared by using the composite material are remarkably increased, the safety, the reliability and the like are far superior to those of the current lithium-sulfur battery of the same type, the operation of a battery management system is very facilitated, and the charge-discharge cycle index and the service life are remarkably improved. The method is simple to operate, convenient to prepare, short in production period and suitable for large-scale production.

This invention relates to the field of catalysts, specifically to a polyethylene catalyst and its preparation method, as well as ultra-high molecular weight polyethylene and its preparation method. The method includes the following steps: (1) under diluent conditions, a magnesium halide precursor, an alcohol compound, and a first internal electron donor undergo a first contact reaction to obtain a first reaction solution; (2) a second internal electron donor is added to the first reaction solution to undergo a second contact reaction to obtain a second reaction solution; (3) a titanium precursor is added to the second reaction solution to undergo a third contact reaction to obtain a third reaction solution; (4) a haloalkane is added to the third reaction solution, followed by a third internal electron donor to undergo a fourth contact reaction. The catalyst prepared by this invention exhibits good catalytic performance.

The invention belongs to the technical field of material science and engineering, and relates to a method for preparing a high-orientation high-reflectivity graphene film through vapor pressure assisted stretching reduction, and the method comprises the following steps: carrying out isotropic stretching and vapor treatment on a graphene oxide film at the same time, namely heating a mixed solution of a hydrogen iodide aqueous solution and ethanol until the mixed solution is vaporized, and carrying out heat preservation at 90-120 DEG C for 6-24 hours, the volume ratio of the hydrogen iodide aqueous solution to the ethanol is 1: (2-5). According to the method, the graphene film is subjected to isotropic tensile stress in the reduction process, so that wrinkles and ripples generated by thermal fluctuation and interlayer spacing change are effectively eliminated, and the flatness of the graphene sheet layer is improved.