2476 results about "Acetylene" patented technology

The invention relates to the field of lithium battery negative electrode materials, and particularly discloses a silicon-carbon composite negative electrode material for a lithium ion battery and a preparation method of the silicon-carbon composite negative electrode material. The method comprises the following steps: preparing a porous carbon substrate, and depositing silicon nanoparticles in pores and on the surface of the porous carbon substrate by adopting a fluidized bed chemical vapor deposition process and taking silane as a silicon source to obtain a silicon-carbon core material; continuously carrying out carbon coating on the surface of the silicon-carbon core material in the fluidized bed by taking acetylene as a carbon source to form a carbon coating layer; and leading out the obtained material from the fluidized bed, taking acetylene as a carbon source, and carrying out carbon coating on the surface of the primary carbon coating layer again by adopting the rotary furnace to form a secondary carbon coating layer. According to the preparation method, a porous carbon matrix and double-layer functional carbon coating process is adopted, so that the volume expansion of silicon in the circulation process is remarkably inhibited, the interface side reaction is reduced, and the circulation stability of the material is effectively improved.

The invention relates to an extended-range resonant photoacoustic cell for acetylene detection and a detection method thereof, belongs to the technical field of partial discharge in a high-voltage insulating transformer, and provides the extended-range resonant photoacoustic cell for acetylene detection in order to solve the problem that a photoacoustic spectrum detection device is poor in sensitivity. Comprising a first buffer cavity, a second buffer cavity, a laser, four reflectors, a photoelectric detector and a controller which are arranged in a shell, and a resonance gas chamber is arranged between the first buffer cavity and the second buffer cavity so as to communicate the first buffer cavity with the second buffer cavity; the laser is located on one side of the first buffer cavity. The four reflectors are symmetrically arranged in the first buffer cavity and the second buffer cavity in pairs respectively; the photoelectric detector is used for detecting optical signals; the microphone is used for sound signals; the controller is used for processing the optical signal and the acoustic signal to obtain a detection result of the characteristic gas. The four reflectors not only can increase the absorbance, but also can realize continuous monitoring and improve the detection sensitivity.

The invention relates to the technical field of acetylene cracking furnace production monitoring, and particularly discloses a CO laser detection system based on a thermal radiation background, which is used for solving the problem that an existing monitoring system is difficult to accurately distinguish CO and water vapor signals because thermal radiation and water vapor generated by high temperature in an existing ethylene cracking furnace interfere infrared absorption measurement of CO. Comprising a quantum cascade laser, a pyroelectric detector, a data processing unit and a signal analysis module, a reference light intensity adjusting module utilizes temperature, humidity and pressure data obtained by an environment parameter sensing module in real time to adjust the CO absorption coefficient through an environment correction factor, the reference light intensity is dynamically calculated and corrected according to the reference light intensity, and the signal analysis module analyzes the signal. The data processing unit is used for dynamic correction of CO concentration monitoring; a CO signal is effectively extracted under a thermal radiation background through a quantum cascade laser and a light beam modulation technology, environment correction and real-time monitoring are combined, CO concentration abnormity is accurately recognized, early warning is given out, and the monitoring sensitivity and reliability are improved.

The invention relates to a preparation method and application of an organosilicon / MOF-303 mixed matrix membrane, a silicon source precursor is uniformly dissolved in an ethanol solvent, then a mixture of water and hydrochloric acid is added according to a certain proportion, a water bath heating reaction is carried out for a period of time to obtain an organosilicon sol, prepared MOF-303 powder is added into the organosilicon sol according to a certain proportion, and the organosilicon / MOF-303 mixed matrix membrane is obtained. The preparation method comprises the following steps: uniformly mixing the raw materials through ultrasound to obtain a separation layer sol, coating the prepared separation layer sol on a ceramic support body through a hot coating method, and calcining in an air atmosphere for a period of time to obtain the MOF-303 / mixed matrix membrane. An organic silicon substance BTESA with a rigid acetylene bridge structure is preferably selected as a precursor, an MOF-303 material with a high specific surface area is doped into the precursor, the pore channel structure of the membrane is modified, more adsorption sites are provided for water molecules, and the composite membrane material with the optimal separation performance is obtained by optimizing the composite proportion.

The invention discloses a preparation method and application of a conjugated microporous polymer microsphere filler with a hollow structure, silicon dioxide nanospheres are placed in an organic solvent, after uniform ultrasonic dispersion, 1, 3, 5-triacetylene benzene and 2, 6-dibromo-3-aminopyridine are added, after a catalyst is added, a stirring reaction is carried out in a nitrogen atmosphere to obtain yellow powder, and the yellow powder is dried to obtain the conjugated microporous polymer microsphere filler with the hollow structure. Etching with hydrofluoric acid, cleaning the treated product until the filtrate is transparent and colorless, and drying in vacuum to obtain the conjugated microporous polymer microsphere filler with the hollow structure. Nanoscale holes are formed in the hollow-structure conjugated microporous polymer microsphere filler, so that the hollow-structure conjugated microporous polymer microsphere filler has good heat insulation performance and good heat stability at high temperature, and can be used as a heat-resistant performance enhancing filler.

The invention relates to Omarlliptin, in particular to a novel method for preparing Istradafylline, and relates to a preparation method of Istradafylline, in particular to a preparation method of Istradafylline. The method comprises the following steps: carrying out coupling reaction on a compound Ia and TMS acetylene to obtain an intermediate Ib; carrying out bromination reaction on the intermediate Ic under the action of NBS (N-bromosuccinimide) to obtain an intermediate Id; carrying out substitution reaction on the intermediate Id and tert-butyl carbamate under the action of potassium tert-butoxide to obtain an intermediate Ie; reacting the intermediate Ie with paraformaldehyde to obtain an intermediate If; carrying out cycloaddition reaction on the intermediate If and the intermediate Ib to obtain a key intermediate Ig; carrying out asymmetric catalytic hydrogenation reduction on the intermediate Ig to obtain an intermediate Ih; and removing a protecting group from the intermediate Ih in a hydrochloric acid and ethyl acetate system to obtain a final product. The method is short in route, simple and convenient to operate, mild in condition, high in reaction yield, environment-friendly and easy for industrial production, and dangerous and highly toxic products are prevented from being used and hazardous chemicals are supervised. # imgabs0 #

The invention discloses a preheating furnace control method and electronic equipment. The method comprises the steps that an initial flow value, a real-time flow value and a target flow value of a preheating furnace inlet and a real-time outlet temperature and a target outlet temperature of a preheating furnace outlet are obtained; according to the initial flow value, the real-time flow value is adjusted to be larger than or equal to the initial flow value; and according to the target flow value and the target outlet temperature, a preheating furnace control strategy is executed, so that the real-time flow value is larger than or equal to the target flow value, and the real-time outlet temperature is larger than or equal to the target outlet temperature. After the inlet gas flow of the preheating furnace is adjusted to the initial value, the strategy of adjusting the flow and the outlet temperature of the preheating furnace is set at the same time in stages, so that the operation error rate is reduced, and simultaneous heating and quantity increasing of the natural gas preheating furnace of the acetylene device are automatically and flexibly achieved.

The invention discloses a coal gasification slag-based backfill material for replacing flow-state solidified soil, a preparation method and an application, utilizes a synergistic gelling effect among three raw materials, breaks through a material strength forming mechanism of traditional flow-state solidified soil, solves the problems of multiple components and high cost of a flow-state solidified soil material in the prior art, and has the advantages of low raw material cost, low raw material cost, low raw material cost, low raw material cost and the like. And the product popularization is facilitated. The specific scheme is as follows: the coal gasification slag-based backfill material for replacing the fluidized stabilized soil comprises coal gasification slag, carbide slag and titanium gypsum, the ratio of the coal gasification slag to the carbide slag to the titanium gypsum is 6-8: 1.5-3.5: 0.5-1.5, and an alkaline activator is also added; the coal gasification slag is a slag block with a set particle size formed after slag at the bottom of a gasification furnace is cooled, the carbide slag is waste slag which takes calcium oxide as a main component after acetylene gas is obtained by hydrolyzing calcium carbide, and under the action of an exciting agent, the coal gasification slag and the carbide slag are fully activated to release polyhedrons; part of the polyhedrons form a gelling product so as to improve the early strength of the coal gasification slag-based backfill material.

The invention is applicable to the technical field of nano material preparation, and provides a preparation method of a two-dimensional acetylene-rich carbon / molybdenum sulfide heterostructure hydrogen production catalyst, which comprises the following steps: adding molybdenum sulfide into a solution to prepare a suspension A; adding soluble cuprous salt into the turbid liquid A in an inert atmosphere to obtain a mixed liquid B; alkynyl benzene is added into an organic solvent, and a mixed solution C is obtained; dropwise adding the mixed solution C into the mixed solution B under a continuous stirring condition, and reacting to obtain a mixed solution D; centrifuging the mixed solution D to obtain a precursor E; and cleaning the precursor E, and carrying out vacuum drying to obtain the two-dimensional acetylene-enriched carbon / molybdenum sulfide heterostructure hydrogen production catalyst. No additive is needed in the preparation process, and the product purity is high; by constructing a special two-dimensional heterostructure, the problem of molybdenum sulfide is solved, and the intrinsic activity and stability of the material are remarkably improved. The preparation method has the advantages of easily available raw materials, simple process, low cost and environmental protection, and is suitable for industrial production.

The invention discloses a nano silicon dioxide loaded ruthenium-copper bimetallic catalyst as well as preparation and application thereof, and belongs to the technical field of acetylene hydrogenation reaction catalysts. A strong electrostatic adsorption method is adopted, nano silicon dioxide is used as a carrier, the pH of a solution is higher than the isoelectric point of the carrier through adjustment of ammonia water, and the carrier is negatively charged; in ammonia water, Cu and Ru respectively form positively charged metal complexes, and metals are anchored on the surface of the carrier under the action of strong electrostatic adsorption to prepare the atomic-scale dispersed ruthenium-copper bimetallic catalyst for acetylene selective hydrogenation reaction. When the prepared catalyst is used for catalyzing an acetylene hydrogenation reaction and the reaction temperature exceeds 170 DEG C, the acetylene conversion rate can reach 100%, and the ethylene selectivity is 90%-100%. And the catalyst has excellent stability, and can keep activity for a long time without obvious deactivation phenomenon.

The invention relates to the technical field of lithium ion batteries, in particular to a carbon source mixed gas CVD coated silicon-carbon negative electrode material, a preparation method and a lithium ion battery. The preparation method comprises the following steps: 1) preparation of a silicon-carbon material: placing porous carbon in equipment, regulating and controlling the gas speed and the dynamic rotation speed of the equipment to uniformly disperse the porous carbon, heating to 380-650 DEG C, and introducing silane mixed gas with the concentration of 5-50% to form the silicon-carbon material; and 2) coating the silicon-carbon material with mixed gas carbon: introducing mixed gas sources with different proportions into equipment, regulating and controlling the gas speed and the dynamic rotation speed of the equipment to uniformly disperse the mixed gas sources, and heating to 450-700 DEG C to realize uniform carbon coating on the surface of the silicon-carbon material. According to the invention, the problem of explosion caused by self-polymerization reaction of single acetylene is solved; and moreover, the uniform carbon coating isolates the side reaction problem caused by direct contact between the electrolyte and the nano silicon, and the stability of the silicon-carbon material is improved.

The invention discloses multifunctional acetylene carbon black as well as a preparation method and application thereof. The preparation method comprises the following steps: blending triethylenetetramine hexaacetic acid and acetylene carbon black in a mass ratio of (0.05-0.5): 100, and then carrying out esterification reaction under a vacuum condition, thereby obtaining the multifunctional acetylene carbon black. The preparation method comprises the following steps: modifying acetylene carbon black by adopting triethylenetetramine hexaacetic acid, and carrying out esterification reaction on triethylenetetramine hexaacetic acid with six carboxyl functional groups and acetylene carbon black with a hydroxyl functional group, so that the acetylene carbon black is modified, and the acetylene carbon black becomes multifunctional acetylene carbon black. The acetylene carbon black modified with a large number of carboxyl groups and amide groups on the semiconductive wrapping tape form rich hydrogen bonds, so that the compatibility of the acetylene carbon black and the semiconductive wrapping tape is improved.

The invention belongs to the technical field of high-purity gas preparation and catalysis, and discloses a copper-iron double-component composite catalyst for removing trace acetylene and ethylene in petrochemical byproduct hydrogen chloride gas to prepare electronic grade hydrogen chloride gas, and a preparation method of the copper-iron double-component composite catalyst comprises the following steps: immersing activated carbon in hydrochloric acid; washing the activated carbon carrier with deionized water until the pH is neutral, and drying to obtain the pretreated activated carbon carrier; and impregnating the active component on the pretreated active carbon carrier, carrying out ultrasonic-assisted impregnation, standing, and drying, thereby obtaining the product, the active components are Fe metal salt and Cu metal salt. According to the method, trace acetylene and ethylene in the petrochemical byproduct hydrogen chloride gas are catalyzed to react with the hydrogen chloride gas at the same time, so that acetylene and ethylene are removed at the same time, and the acetylene and ethylene removal step in the existing hydrogen chloride purification process is simplified. Compared with a traditional method, the reaction efficiency of preparing the electronic-grade hydrogen chloride gas is remarkably improved.

A liquid crystal element includes two substrates with a transparent conductive film, the substrates being arranged such that transparent conductive films face each other, and a liquid crystal-polymer composite film which is sandwiched between the two substrates with a transparent conductive film, in which the liquid crystal-polymer composite film contains an acetylene alcohol.

The invention provides a metal doped silicon carbon negative electrode material and a preparation method thereof, and the preparation method comprises the following steps: a modified amorphous carbon material and a metal silane precursor are respectively prepared, the particle size of the modified amorphous carbon material is 7-8 [mu] m, and the internal pore size of the modified amorphous carbon material is 0.1-10 nm; the modified amorphous carbon material is placed in a chemical vapor deposition reactor, nitrogen is introduced, the temperature is increased to 500-700 DEG C, then composite gas is introduced, the deposition reaction is carried out for 100-800 minutes, a pre-product is obtained, the composite gas comprises a metal silane precursor, doping auxiliary gas and acetylene gas, and the doping auxiliary gas is used for regulating and controlling growth of sediments; and heating the pre-product to 750-850 DEG C for 10-30 minutes, cooling the pre-product to 500-600 DEG C, introducing acetylene gas again, and keeping the temperature for 30-300 minutes to obtain the metal-doped silicon-carbon negative electrode material. Therefore, the electrochemical performance and the cycle life are effectively improved.

The invention relates to the field of new energy battery buffer parts, in particular to an anti-static foaming silica gel buffer part for a new energy battery and a preparation method of the anti-static foaming silica gel buffer part. The anti-static foaming silica gel buffer part is prepared by mixing and foaming anti-static mixed rubber, a foaming agent, hydrogen-containing silicone oil, an inhibitor and a platinum catalyst, the anti-static rubber compound is prepared from the following raw materials in percentage by weight: 37-50% of methyl vinyl silicone rubber raw rubber, 38-45% of white carbon black, 8-15% of anti-static filler and 1-3% of hydroxyl silicone oil; the antistatic filler is composed of an antistatic agent and a silane-containing active agent; the antistatic agent is composed of acetylene carbon black and a single-walled carbon nanotube. Under the action of the silane-containing active agent, the acetylene carbon black and the single-walled carbon nanotubes are interwoven to form a stable supporting antistatic skeleton structure, so that static electricity can be effectively conducted, static electricity accumulation is avoided, the structure is kept stable in long-term use, and the compression resilience and antistatic durability of the buffer part are ensured.

Provided is an ink jet ink including water, a pigment, a surfactant (A) which is an acetylene glycol-based nonionic surfactant, a surfactant (B) which is a compound represented by Formula (1), and an organic solvent (C), in which the organic solvent (C) includes a glycol ether (c-1) which is at least one selected from the group consisting of an alkylene glycol monoalkyl ether having a boiling point of 250°C or lower and a polyalkylene glycol monoalkyl ether having a boiling point of 250°C or lower. In Formula (1), R1 and R2 each independently represent a branched alkyl group having 3 to 20 carbon atoms, and n represents an integer of 1 to 20.

The invention discloses a non-noble metal copper-based catalyst as well as a preparation method and application thereof. The preparation method comprises the following steps: dissolving a copper source and a second metal source in a solvent to obtain a precursor prefabricated solution, dropwise adding an alkaline solution to adjust the pH value of the precursor prefabricated solution to 7-13, keeping for 4-12 hours in an oil bath environment of 60-100 DEG C, aging, filtering, washing and drying to obtain a solid precursor; and putting the obtained solid precursor into a muffle furnace, heating to 200-800 DEG C in an air atmosphere, and roasting for 1-9 hours to obtain the non-noble metal copper-based catalyst. Wherein the second metal source is an aluminum source, a magnesium source, a zinc source, a zirconium source or a cobalt source; the catalyst can realize complete conversion (100%) of acetylene and selectivity of more than 95% of ethylene at a low temperature (180 DEG C) and a high space velocity (18000 ml / gcat / h), does not inactivate after more than 150 h under repeated cycle tests, and has important significance for industrial production.

The invention discloses a silicon-carbon negative electrode material preparation method, which comprises: (S1) uniformly mixing a water-soluble resin and a transition metal salt aqueous solution, and drying to obtain a resin-loaded metal salt composite material; (S2) carrying out carbonization treatment on the resin-loaded metal salt composite material, and then carrying out reduction treatment to obtain metal-loaded porous carbon; (S3) placing the metal-loaded porous carbon in a mixed atmosphere containing carbon dioxide and acetylene, performing in-situ growth of carbon nanotubes in the porous carbon, and performing acid pickling to obtain modified porous carbon; and (S4) by taking the modified porous carbon as a substrate, sequentially carrying out silicon deposition and carbon coating to obtain the silicon-carbon negative electrode material. According to the preparation method of the silicon-carbon negative electrode material disclosed by the invention, the porous carbon is synthesized in situ, and the carbon nanotubes grow in the porous carbon in situ, so that more buffer spaces are provided for volume expansion of nano silicon particles from the angle of substrate preparation, and the long cycle stability of the silicon-carbon negative electrode material is remarkably improved.

The invention discloses an application of a boron nitride non-metal catalyst in acetylene hydrochlorination reaction, and a preparation method of the boron nitride non-metal catalyst comprises the following steps: 1) adding a boron-containing compound, a nitrogen-containing compound and a halide into deionized water, and fully dissolving to obtain a mixed solution; secondly, adding a template agent KIT-6 into the mixed solution, and uniformly stirring; transferring into a hydrothermal reaction kettle with a polytetrafluoroethylene lining, purging air in the reaction kettle with nitrogen, sealing, and reacting at 250-400 DEG C for 20-40 hours; and 2) after the reaction is finished, carrying out suction filtration and washing on a product with deionized water, transferring the product into an HF solution to be soaked so as to remove the residual template agent, then washing the product with deionized water until the product is neutral, and drying the product to obtain the boron nitride non-metal catalyst. The preparation method of the catalyst is simple, and the catalyst has high activity and high stability at a low reaction temperature.

The invention discloses a system for preparing acetylene by partial oxidation of natural gas, which comprises a natural gas preheating furnace, an oxygen preheating furnace and an acetylene furnace, both the natural gas preheating furnace and the oxygen preheating furnace are communicated with the acetylene furnace, the acetylene furnace is communicated with a quenching water inlet pipe, and a pyrolysis gas outlet of the acetylene furnace is directly connected with a YT membrane dust remover. According to the scheme, the problems that in the prior art, a carbon black water system is large in carbon black removal difficulty and high in carbon black post-treatment cost, VOCs and carbon black floating influence the environment when carbon black is removed through an open-type carbon black water tank, waste heat of the system is difficult to utilize, and wet carbon black adheres to the inner wall of a pyrolysis gas pipeline and blocks the pipeline are solved.

The utility model discloses a heating structure for pipeline welding heat treatment, and particularly relates to the technical field of pipeline welding, the device is driven by reset springs of a plurality of arc-shaped seats, an assembly ring can automatically contract to adapt to pipelines with different thicknesses, additional adjustment is not needed, the application range of the device is widened, and the flexibility of the device is improved. The nozzle connected with the acetylene heating device can uniformly heat around the pipeline, uniform temperature distribution of the surface of the pipeline is guaranteed, welding quality and efficiency are improved, supporting pieces on the two sides of the device comprise guide wheels, the guide wheels make contact with the pipeline through elastic force of telescopic springs, the assembly ring is stably supported, and excessive shrinkage is prevented from affecting the heating effect. Due to the arrangement of the multiple guide wheels, the heating device can flexibly move in the axis direction of the pipeline, the heating position is changed, the welding requirements of different parts are met, the operation convenience and efficiency are improved, an operator only needs to sleeve the pipeline, complex adjustment and operation steps are not needed, the operation difficulty and time cost are reduced, and the working efficiency is improved. And the working efficiency is improved.

A method for producing one or more hydrocarbons, includes subjecting a first feed stream to a steam cracking to obtain a first product stream and subjecting a second feed stream containing ethane to an oxidative dehydrogenation to obtain a second product stream At least a portion of the first product stream is subjected to a treatment to obtain hydrocarbon fractions. The treatment includes a selective hydrogenation of hydrocarbons having two carbon atoms and a demethanization. At least a portion of the second product stream is subjected to a trace removal, which comprises the removal of oxygen and / or acetylene, to obtain an subsequent stream. At least a portion of the subsequent stream is fed to the treatment at a position downstream of the selective hydrogenation and upstream of the demethanization. A portion of the subsequent stream is subjected to a carbon dioxide removal upstream of the feed point into the treatment.

This invention relates to a method for using a low-content ruthenium-based catalyst modified with nitrogen and oxygen ligands in the hydrochlorination of acetylene. The invention utilizes 2-pyridine carboxylate as a ligand, commercial activated carbon as a support, trace amounts of ruthenium as the main active component, and water as a solvent. An improved synthesis procedure yields a low-content ruthenium-based catalyst with ruthenium ions coordinated by a modifier and commercial activated carbon as a support, significantly improving catalyst performance while reducing ruthenium content. This catalyst exhibits high activity and vinyl chloride selectivity in the fixed-bed hydrochlorination of acetylene to vinyl chloride, and its low cost makes it highly valuable for industrial applications. The ruthenium loading is 0.1%, and the reaction gas space velocity is 170 h⁻¹. ‑1 V (C2H2) / V (HCl) With a ratio of 1:1.05 and a reaction temperature of 180℃, the acetylene conversion rate can reach 84.3%, the vinyl chloride selectivity is greater than 99%, and the activity remains basically unchanged within 10 hours.

The invention discloses a preparation method of an ultra-stable supported Pd-based catalyst and application of the ultra-stable supported Pd-based catalyst in acetylene selective hydrogenation reaction, the catalyst is composed of an active component, a carrier and auxiliaries, the active component is precious metal palladium, the carrier is silicon dioxide, and the auxiliaries are non-active metal silver and alkali metal. The catalytic performance of the catalyst in acetylene selective hydrogenation reaction is effectively improved through the dual modification and isolation effects of alkali metal and non-active metal silver on active components, and the 0.1% Pd, 1% Ag and 0.5% Na / SiO2-R500 supported catalyst gives consideration to acetylene conversion rate and ethylene selectivity within a wide operation temperature window (100-300 DEG C). The catalyst is not obviously inactivated in 100-hour stability tests at 75 DEG C, 100 DEG C, 150 DEG C and 200 DEG C, the selectivity is always maintained at 84% or above, and the catalyst is simple in preparation method and low in cost.

The invention provides a transformer partial discharge fault diagnosis method and system, and belongs to the technical field of transformers. The method comprises the following steps: inputting an ultrasonic signal generated during partial discharge of a transformer into a partial discharge ultrasonic detection and analysis model to obtain current partial discharge data, and judging whether the current partial discharge data exceeds a preset partial discharge threshold value or not to obtain a primary judgment result; inputting the content data of the dissolved gas in the transformer oil into the acetylene characteristic gas detection and analysis model to obtain acetylene characteristic gas content data, and judging whether the acetylene characteristic gas content data exceeds a preset acetylene characteristic gas content threshold value or not to obtain a secondary judgment result; and determining a final judgment result of the partial discharge state of the transformer based on the primary judgment result and the secondary judgment result. The accuracy, sensitivity and anti-interference capability of transformer partial discharge real-time detection and fault diagnosis are improved, and the purpose of automatic and precise detection of transformer partial discharge is achieved.

The invention discloses a preparation method of an all-solid-state lithium-sulfur battery composite positive electrode, which comprises the following steps: weighing raw materials of sodium thiosulfate, hydrochloric acid and a conductive agent (such as one or more of graphene, carbon nanotubes, conductive carbon black and acetylene black) according to a certain proportion, stirring, precipitating, washing and drying to obtain a sulfur-carbon precursor; and performing mechanical ball milling on the precursor and an electrolyte according to a certain proportion, and grinding with a binder to obtain a composite positive electrode, and taking the composite positive electrode as the positive electrode of the all-solid-state lithium-sulfur battery. According to the invention, the problem of non-uniform lithium ion transmission caused by large particle size of active substance sulfur is solved, so that the utilization rate of the active substance is improved; meanwhile, the problem of non-uniform dispersion of the active substance sulfur and the conductive agent carbon is solved, so that the cycle stability of the battery is improved; in addition, the addition of the binder enhances the contact of each component in the composite positive electrode, thereby obtaining more excellent electrochemical performance.

The invention relates to a double-layer coated silicon-carbon composite material, a preparation method thereof and a lithium ion battery. The preparation method comprises the following steps: adding a porous carbon precursor with a particle size D50 of 5-10 [mu] m into a chemical vapor deposition furnace, and introducing monosilane for 100-800 min for silicon deposition to obtain a silicon-carbon composite material; introducing acetylene gas, and reacting for 50 to 500 minutes to obtain a primary carbon-coated silicon carbon composite material; dissolving lithium nitrate in absolute ethyl alcohol, adding the primary carbon-coated porous silicon-carbon composite material, stirring and dispersing, dropwise adding an ammonium dihydrogen phosphate solution into the solution, and reacting at 60-80 DEG C for 1-3 hours; and carrying out suction filtration, cleaning and drying on the reacted material to obtain the porous silicon-carbon composite material with the double-layer coating structure. Through the double-layer coating structure, the electrochemical stability and mechanical stability of the material are improved, and meanwhile, the application scene of the silicon-carbon negative electrode material at low temperature is expanded.

The invention relates to the field of lithium battery negative electrode materials, and particularly discloses a high-energy silicon-carbon composite negative electrode material for a lithium ion battery and a preparation process of the high-energy silicon-carbon composite negative electrode material. The preparation method comprises the following steps: mixing resin-based activated carbon and biomass activated carbon with specific pore volume and compressive strength according to a mass ratio of 1: (0.2-0.3) to obtain a porous carbon matrix; depositing silicon nanoparticles on the porous carbon substrate by adopting a fluidized bed chemical vapor deposition process; depositing a thin carbon layer on the surface of the silicon-carbon core material by taking acetylene as a carbon source; and carrying out secondary carbon coating by adopting a rotary furnace to form the silicon-carbon negative electrode material. According to the composite negative electrode material prepared by the process, the resin-based activated carbon is used as a main matrix, so that the influence of more impurities and non-uniform pore structure distribution of biomass activated carbon on the cycling stability and conductivity of the silicon-carbon negative electrode material is reduced, and the problems of volume expansion and conductivity of the silicon-based negative electrode material are solved.

To provide a metal paste for joining that prevents the occurrence of solvent separation even in high-humidity conditions while containing PEG, a method for producing a joint body using the same, and a joint body.SOLUTION: A metal paste for joining contains metal particles, a dispersion medium, and a reductant. The metal paste contains, as the reductant, polyethylene glycol. The metal paste contains a compound A having, within its molecule, at least one group selected from the group consisting of an amino group, a carboxyl group, and an acetylene group, as well as a hydroxy group.SELECTED DRAWING: None