208results about How to "Block direct contact" patented technology

The invention discloses a method for preparing transformer insulating heat conduction oil. The transformer insulating heat conduction oil comprises the following components in parts by mass: 50-65 parts of mineral base oil, 10-15 parts of castor oil, 5-10 parts of peanut oil, 0.5-3 parts of oil-soluble nano titanium dioxide, 6-12 parts of glycerol triacetate, 0.1-0.2 part of a surfactant, 0.01-0.02 part of an antioxidant, 0.5-1.5 parts of an antistatic agent and 1-3 parts of modified nano boron nitride granules, wherein the base oil is mineral oil of which the kinematic viscosity is 20-35mm<2>/s at 100 DEG C. The transformer insulating heat conduction oil prepared by using the method is good in oil quality, high in oil ignition point, good in insulating property, good in heat conduction property, capable of preventing transformer oil self from generating static electricity to affect the operation of a transformer, moderate in kinematic viscosity, high in flash point, excellent in ,anti-oxidation and anti-aging stability and good in corrosion resistance.

The invention relates to a carbon-coated nano silicon/graphene/cracked carbon layer composition material, a preparation method thereof, and a lithium ion battery including the composition material. The composite material comprises spherical particles formed by uniformly dispersing carbon-coated nano silicon in graphene sheets, and a cracked carbon layer which coats the surfaces of the spherical particles. The carbon-coated nano silicon comprises nano silicon and carbon coating layer which coats the surface of the nano silicon. The method is simple, has excellent process performance and is environment-friendly. The carbon-coated nano silicon/graphene/cracked carbon layer composition material has stable structure and high compact density, has excellent performance when being used as an anode material of the lithium ion battery, has high anode capacity, excellent rate capability and cyclic performance, is more than 1500 mAh/g in first-time reversible capacity, is more than 90% in first-time coulomb efficiency and is more than 90% in 500-time cyclic capacity retention ratio and has low expansion.

The invention provides a device and method for inner bore type component brush plating. The device comprises a workpiece to be plated, a workpiece clamping sealing device, a plating pen special for inner bore brush plating, and a plating pen rotary actuator. The workpiece to be plated and the clamping sealing device together form a container having an opening at the top; in plating process, the workpiece is the cathode, and the plating pen is the anode. The device and method realize that plating is prepared at the surface of the inner bore of the inner bore type component by using the technology of brush plating, thereby being applied to strengthening for new workpiece and also being applied to batch repair and remanufacturing for damaged pieces.

The invention discloses a lithium metal composite negative electrode with a lithium-philic and lithium-phobic gradient structure, and a preparation method thereof. The lithium metal composite negativeelectrode is of a three-layer structure, wherein the bottom layer is a 3D porous matrix framework, the middle layer is a lithium-philic layer compounded on the 3D porous matrix framework, and the toplayer is a lithium-phobic layer compounded on the surface of the lithium-philic layer. The preparation method comprises the following steps: (1) preparing a 3D porous matrix skeleton, and cleaning; (2) transferring the 3D porous matrix skeleton to a prepared precursor solution; (3) forming a lithium-philic layer on the 3D porous matrix skeleton in situ by adopting a solvothermal method; (4) modifying a lithium-phobic layer on the lithium-philic layer; and (5) finally filling with lithium by adopting an electro-deposition method. According to the invention, the overpotential in the lithium metal nucleation and deposition process can be reduced by utilizing the lithium-philic layer, and the uniform deposition and dissolution of the lithium metal in the continuous cycle process are realizedby utilizing the characteristic that the lithium ion diffusion is promoted by utilizing the lithium-phobic layer, so that the growth of dendritic crystals is effectively avoided, and the cycle life ofthe lithium metal battery is greatly prolonged.

The invention discloses a BN-coated cobalt-free Ni-Mn solid solution Ni-based positive electrode material. The BN-coated cobalt-free Ni-Mn solid solution Ni-based positive electrode material has a structural formula of LiNixMn1-xO2. a BN. In the structural formula, x is greater than or equal to 0.5 and less than 1, a is greater than 0 and is less than or equal to 0.06 and BN is a coating on the surface of the LiNixMn1-xO2 material. The positive electrode material is coated with BN. The coating can effectively prevent direct contact between a positive electrode material and an electrolyte, has strong acid resistance, can inhibit dissolution of material manganese ions in the electrolyte, realizes a stable material structure and improves material cycling performances.

The invention discloses a porous carbon, nano silicon and carbon core shell structure material and a preparation method thereof. The core shell structure material takes a porous carbon material as a substrate; a middle embedding layer consists of nano silicon; and an outer layer is coated with an amorphous carbon housing. The preparation method comprises the steps of performing moderate temperature etching on a pre-etched substrate carbon material in an inert gas atmosphere, performing high temperature activation, performing aftertreatment to obtain the porous carbon material, mixing the porous carbon material and nano silicon in a solvent, performing grinding to obtain a composite material, mixing the composite material and a carbon source in a solvent, performing spray granulation, and then performing heat treatment in an inert gas atmosphere. According to the material and the method, the first coulombic efficiency and the structure stability of the material are effectively improved.A high-stability silicon-carbon composite cathode active material with reversible capacity 400-650mAh/g can be obtained after mixing with a graphite material. In addition, the composite material is low in production cost, and is suitable for industrial production.

The invention discloses a preparation method of a carbon nanotube/thermosetting resin composite material. The preparation method comprises the following steps of: uniformly mixing 100 parts by weight of thermosetting resin and 0.1-2 parts by weight of carbon nanotube to obtain prepolymer; dividing the prepolymer into a plurality of parts; taking one part of prepolymer, precuring at certain temperature and cooling to obtain a precured sheet; taking another part of prepolymer and pouring on the precured sheet, and then precuring; precuring the rest parts of prepolymer in steps in sequence to obtain a precured body; and curing and post-treating to obtain the carbon nanotube/thermosetting resin composite material. Compared with the carbon nanotube/thermosetting resin composite material prepared by one-time forming in the prior art, the composite material provided by the invention has the advantages of higher dielectric constant, lower dielectric loss angle tangent value, simple and practical preparation method, controllable process and suitability for large-scale production.

The invention discloses an aqueous boron nitride coating capable of binding at a low temperature and being used at a high temperature. The coating is prepared from 15-60 wt% of hexagonal boron nitride, 2-15 wt% of a composite high temperature binder, 1 wt% of carboxymethyl cellulose, 0.5 wt% of a thickener, 1 wt% of cobalt aluminate, 0.2 wt% of isooctanol, and the balance is demineralized water. Apreparation method of the coating comprises the following steps: mixing and stirring carboxymethyl cellulose used as a dispersant, the high-temperature binder, the thickener, cobalt aluminate used asa high-temperature pigment and demineralized water at a normal temperature to form a uniform solution, adding the hexagonal boron nitride and isooctanol used as a defoamer to the solution, and performing stirring until a uniform system is formed. The coating adopts an aqueous system, has no harmful substance volatilization during use, is clean and environmentally friendly, has good adhesion, anddoes not crack or spall in order to effectively block direct contact between a metal melt and the surface of a refractory material. Additionally, the coating has excellent stability and suspension capacity, and the stability and the suspension capacity do not change under high dilution.

The invention discloses a shield tunnel segment structure and a connecting structure thereof. The shield tunnel segment structure comprises a segment body and is characterized in that the segment body is mainly composed of a steel plate layer, a concrete layer wrapping the steel plate layer, and steel mesh reinforcements which are located on the two sides of the steel plate layer correspondingly and embedded in the concrete layer; the lateral edges of the segment body are fixedly provided with metal connectors, the outer sides of the metal connectors are provided with grooves for containing water stops, and the water stops are installed inside the grooves; and an outer protecting layer is arranged on the outer side of the segment body, and the outer protecting layer is a polyurea layer combined on the outer side surface of the segment body. The connecting structure is composed of two adjacently arranged shield tunnel segment structures and a connecting part for connecting the two shield tunnel segment structures. A connecting steel plate is composed of a middle arc-shaped section and flat sections on two sides. The shield tunnel segment structure and the connecting structure thereof have the characteristics that thickness is small, strength is high and the connectors are not prone to damage; and the connector deformation control effect is good, the seam waterproof effect is good, durability is high, and repairing is convenient.

The invention aims to provide a montmorillonite loaded calcium hydroxide antacid which uses montmorillonite loaded calcium hydroxide as the antacid on the basis of acid activation of montmorillonite loaded calcium hydroxide, and solves the conventional problem caused by direct contact of active components of the antacid and the gastric mucosa, wherein the montmorillonite has a gastric mucosa protection function simultaneously. The montmorillonite loaded calcium hydroxide antacid is characterized in that the antacid takes medicinal montmorillonite as the raw material, the montmorillonite is taken as a carrier after acid activation, loaded calcium hydroxide serves as an active ingredient, fatty acid is adopted for surface modification, the carrier of the obtained antacid is stable and insoluble, calcium hydroxide serving as the active ingredient can be continuously and firmly loaded on the carrier, the alkaline intensity is weakened, excessive taking of the antacid cannot cause too high gastric pH, and further, the carrier improves the dispersibility of calcium hydroxide serving as the active ingredient and forms a protective barrier, so that mucosa stimulation is avoided.

The invention discloses a novel tunnel segment structure and a stress monitoring device thereof, and relates to the technical field of tunnel laying and tunnel and underground engineering. According to the key points of the technical scheme, the novel tunnel segment structure includes novel lining segments capable of being spliced into unit tubes, sealing gaskets and pressure sensors, wherein thesealing gaskets and the pressure sensors are arranged at the junctions of the segments. The segments are in a cross shape, grooves and convex strips are arranged at the side edges of the segments alternatively and the segments are connected through the grooves and the convex strips in a joggle-joint mode to form a tunnel. The side walls of the segments are covered with rubber asphalt waterproof coating, and vulcanized ethylene-propylene rubber elastic sealing gaskets are arranged at the joints of the segments. The pressure sensors are arranged above the convex strips. Compared with the prior art, the sliding friction between the segments is increased through the cross-shaped segments, the pipeline structure is more stable, and the joggle-joint structure simplifies the construction process;meanwhile, a pressure monitoring device is additionally arranged for monitoring and recording the pressure subjected by the segments in real time for carrying out risk prevention, and further research is facilitated; and in addition, a waterproof system has certain reference value for the problem of water seepage.

The invention relates to a wet etching chemical transfer method for enhancing surface cleanliness of graphene, which is characterized by comprising the following steps: depositing a metal layer on a metal-substrate-graphene combination, coating an organic colloid layer on the upper surface of the metal, putting in an etching solution to obtain an organic colloid-metal layer-graphene-layer combination, transferring onto a target substrate, removing the organic colloid, and putting the metal-graphene combination into the etching solution until the metal layer is removed, thereby obtaining the transferred graphene. Compared with the traditional wet etching chemical transfer method, the method provided by the invention has the following advantages: the metal layer is deposited on the graphene surface before spin coating of the organic colloid to prevent the direct contact between the graphene and organic colloid, thereby effectively avoiding the residue of the organic colloid on the graphene surface after transfer.

The invention discloses a short carbon fiber aluminum based composite material and a preparation method thereof. The preparation method comprises the steps of surface processing, chemical copper plating, mixing, sintering, etc.; the prepared short carbon fiber aluminum based composite material comprises the following components in percentage by mass: 8-10% of copper plating short carbon fibers, and 90-92% of aluminum powder, wherein the length of the copper plating short carbon fibers is 2-3mm, and the diameter is less than 20 microns; the thickness of a copper plating layer is 1 micron; the particle size of the aluminum powder is 20-100 microns; the measurement result shows that the density of the short carbon fiber reinforced aluminum based composite material is 98.5%, the hardness is 92.38Mpa, the tensile strength is 202.05Mpa, and the bending resistance is 376.05Mpa. With the adoption of the method, the technical problem of low dispersity of short carbon fibers in the composite material can be solved; the prepared short carbon fiber aluminum based composite material is outstanding in performances and meets the use demands of special situations.

The invention provides an electrostatic self-assembling preparation method of graphene/silicon electrode material. The preparation method comprises the following steps: performing full-carbon surfaceoxidation on high-quality graphene by using potassium permanganate and like oxidants to obtain a graphene oxide material with oxygen-containing groups uniformly distributed on the surface of graphenelamella; etching oxide on the silicon particle surface by using hydrofluoric acid, performing charge modification on the nano silicon by using hexadecyl trimethyl ammonium bromide, thereby enabling the nano silicon particles to possess positive charge, and the accomplishing the electrostatic self-assembling with the graphene oxide; preparing an independent self-support film by using a vacuum filtration method, reducing through the hydroiodic acid under the room temperature to obtain the composite electrode material. The oxygen-containing groups on the surface of the graphene oxide material areuniformly distributed, and can be uniformly compounded with the nano silicon particles with the positive charge in the electrostatic self-assembling process, the volume effect of the silicon in the circulation process is inhibited, thereby preventing the silicon from directly contacting the electrolyte, the irreversible capacity is reduced, and the rate performance of the silicon-based material is improved.

The invention discloses an acidizing corrosion inhibitor based on a dimer indolizine derivative and a preparation method and application of the acidizing corrosion inhibitor. The acidizing corrosion inhibitor contains the dimer indolizine derivative; and the dimer indolizine derivative is mainly obtained by further intermolecular dimerization of active alpha-cetyl trimethyl ammonium chloride of heterocyclic alkali such as (substituted) quinolone and (substituted) pyridine under alkali acceleration. The acidizing corrosion inhibitor has good corrosion inhibition under the condition that a common corrosion inhibition synergist such as alkynol does not need to be compounded, the use amount is small, and when the acidizing corrosion inhibitor is used independently, requirements of first-levelto third-level standard in an acidizing corrosion inhibitor performance testing method and an evaluation index SY/T 5405-1996 can be met and are even higher.

Embodiments of the invention provide a non-aqueous organic high-voltage electrolyte additive. The chemical structural formula of the additive is shown in a formula (1); and in the formula, i is 0 or 1, j is 0 or 1, and R1 and R2 are independently selected from the group consisting of oxygen, an alkyl group, a halogenated alkyl group, an alkyloxy group and a halogenated aromatic group. In the process of charging and discharging of a high-voltage lithium ion secondary battery, the non-aqueous organic high-voltage electrolyte additive can promote formation of a layer of a compact and stable SEI protection film on the surface of a positive electrode material, inhibit contact between an electrolyte and electrode active materials and reduce oxygenolysis of the electrolyte on the surfaces of electrodes, thereby improving cycle performance and discharge capacity of the lithium ion secondary battery under the condition of high voltage. Embodiments of the invention also provide a non-aqueous organic high-voltage electrolyte containing the non-aqueous organic high-voltage electrolyte additive and a lithium ion secondary battery.

The invention discloses a supported type mercury-free catalyst for chloroethylene production with an acetylene hydrochlorination method. According to the catalyst, activated carbon is taken as a basic carrier, and the carrier is pre-treated with a high-stability triazine organic compound adopting a rigid plane structure, so that the surface and the pore surface of the carrier are covered with a layer of rigid plane substances, powdering of the carrier in the preparation and use processes is reduced, then a main active component of gold and an auxiliary active component are supported on the pre-treated carrier, and a stable metal coordination compound is formed. Reduction of activated carbon to the active component of gold is reduced, and the dispersity of the active component on the pre-treated carrier is improved. In a reaction for preparing chloroethylene, the stability of the catalyst of the carrier pre-treated with the triazine coordination compound is obviously better than that of an untreated carrier catalyst, besides, when the content of gold is smaller than 0.05%, the stability is still very high, and the mercury-free catalyst is low in cost, high in activity and good in stability.