476 results about "Hydrofluoric acid" patented technology

The invention belongs to the technical field of fuel cell electrode material preparation, and particularly relates to a carbon electrode material for a polypyrrole modified bio-based fuel cell and a preparation method of the carbon electrode material. Comprising the following steps: modifying rice hull low-temperature carbonized powder by sequentially adopting POSS (Polyhedral Oligomeric Silsesquioxane) containing unipolar functional groups and POSS containing polypolar functional groups to obtain modified low-temperature carbonized powder; and carrying out in-situ polymerization on a pyrrole monomer on the surface of the modified low-temperature carbonized powder, and carrying out high-temperature carbonization and hydrofluoric acid corrosion to obtain the polypyrrole modified bio-based fuel cell carbon electrode material. The polypolar functional group POSS not only is beneficial to the in-situ polymerization reaction of pyrrole, but also can form a continuous macromolecular chain, and a net structure is formed on the surface of the whole material. The effect of the unipolar functional group POSS is to improve the stability of the low-temperature carbonized powder in the high-temperature carbonization process, and more importantly, the unipolar functional group POSS is to provide a channel for subsequent hydrofluoric acid corrosion, etch away non-conductive substances and improve the conductivity and specific surface area of the carbon electrode material.

The invention relates to a waste photovoltaic panel recycling method which comprises the following steps: crushing a waste photovoltaic panel until the size of the waste photovoltaic panel is 80-160 meshes, and preparing powder; carrying out acid leaching treatment on the powder, and respectively collecting a leaching solution and a solid material; an acid leaching solution adopted in the acid leaching treatment is a mixed acid aqueous solution of hydrochloric acid and sulfuric acid; the pH of the leachate is adjusted to be neutral with an alkaline agent, then the leachate is mixed with metal iron to be subjected to a replacement reaction, and metal copper is prepared; the solid material is mixed with water, hydrofluoric acid and a flotation agent are added into the obtained mixture for flotation treatment, floats and precipitates are collected respectively, the floats comprise silicon powder, the precipitates comprise glass powder, and the flotation agent comprises one or two of hexadecyl potassium hydrogen phosphate and sodium dodecyl sulfate. According to the recycling method, the silicon powder, the glass powder and the metal copper can be comprehensively recycled from the waste photovoltaic panel.

The utility model discloses a bitter apricot kernel wastewater treatment device which comprises an equipment shell, a water inlet pipe and a water outlet pipe are respectively arranged on the equipment shell, and a wastewater treatment assembly communicated with the water inlet pipe and the water outlet pipe is arranged in the equipment shell; the wastewater treatment assembly comprises a plurality of groups of apricot shell adsorption tanks which are connected in series, apricot shells are filled in the apricot shell adsorption tanks and are used as adsorbents, the apricot shells adsorbing hydrocyanic acid are subjected to carbonization treatment, and the hydrocyanic acid is destroyed in the carbonization treatment process and forms a part of pyroligneous liquor; the hydrofluoric acid on-line detector is arranged at the downstream of the apricot shell adsorption tank and is used for detecting the content of hydrofluoric acid in the treated wastewater; the control valve group is connected to the water inlet pipelines and the water outlet pipelines of the apricot shell adsorption tanks and is used for controlling the working states of the multiple groups of apricot shell adsorption tanks. The device is efficient in use, easy to operate, low in maintenance cost, safe and reliable, hydrofluoric acid is eliminated in the carbonization process, waste water is recycled, and water resources are saved.

The invention discloses a lithium ion capacitor negative electrode based on an MXene carbon nanotube composite material and a preparation method thereof, and the main points of the technical scheme are that the lithium ion capacitor negative electrode based on the MXene carbon nanotube composite material is composed of an MXene sheet layer, a hydroxyl modified carbon nanotube and a binder; the MXene sheet layer is Ti3C2Tx, the interlayer spacing is 1.0-1.3 nm after the MXene sheet layer is etched by hydrofluoric acid, and the content of-OH functional groups on the surface accounts for 40-60% of the total functional groups; the diameter of the hydroxyl-modified carbon nanotube is 10 to 30 nm, the length of the hydroxyl-modified carbon nanotube is 500 to 2000 nm, and the hydroxyl modification degree of the hydroxyl-modified carbon nanotube is 2.5 to 4.0 mmol / g; the mass ratio of the MXene sheet layer to the hydroxyl modified carbon nanotube is 7: 3-8: 2, and the MXene sheet layer and the hydroxyl modified carbon nanotube are combined through hydrogen bonds to form a layered porous structure.

The invention provides a wet purification process suitable for silicon and precious metal of a waste photovoltaic laminated piece, which comprises the following steps of: immersing a waste crystalline silicon battery piece into a NaOH solution, and removing an aluminum wire on the surface of the crystalline silicon battery piece to obtain a dealuminized crystalline silicon piece; the dealuminated crystal silicon wafer is subjected to acid pickling, and a silver-removed crystal silicon wafer and silver leaching liquid are obtained; removing impurities from the silver-removed crystal silicon wafer through a hydrofluoric acid solution to obtain a high-purity crystal silicon wafer; and extracting the silver elementary substance from the silver leachate through a hydrazine hydrate reduction method. According to the wet purification process, the waste crystalline silicon battery piece can be subjected to high-purity recovery, and the high-purity crystalline silicon wafer and the silver elementary substance can be obtained.

The invention is suitable for the technical field of composite materials, and provides a laminated composite material toughening intermediate layer and a preparation method thereof, and the preparation method comprises the following steps: obtaining an aramid short fiber wet-laid non-woven felt by using a processing method of a wet non-woven material; then the aramid fiber surface is activated through hydrofluoric acid etching; the preparation method comprises the following steps: grafting soluble polyether-ether-ketone resin with an active end group on the surface of the aramid fiber, and impregnating the aramid fiber at the same time; and the polyetheretherketone resin grafted on the surface of the aramid fiber is re-endowed with crystallinity through acidification reduction reaction of the polyetheretherketone resin grafted on the surface of the aramid fiber. According to the invention, the interface bonding performance of the aramid fiber toughening middle layer in the laminated composite material is regulated and controlled, the interlayer toughness of the carbon fiber reinforced polyether-ether-ketone composite material laminated board can be effectively improved while the original crystallinity of the polyether-ether-ketone resin is maintained, the possibility of interlayer cracking can be obviously reduced, a brand new scheme is provided for interlayer toughening of such materials, and the application prospect is broad. The material has potential application prospects in the fields of aerospace special materials and the like.

The invention relates to the technical field of high-purity quartz purification methods, in particular to a high-purity quartz green low-consumption purification method which comprises the following steps: S1, plasma-assisted crushing pretreatment; s2, complex acid leaching-microwave synergistic impurity removal; s3, fluidized chloridizing roasting; s4, nano bubble water washing-targeted adsorption; s5, performing vacuum heat purification; according to the purification method of the high-purity quartz, the step of complex acid leaching-microwave synergistic impurity removal is adopted, highly toxic hydrofluoric acid in a traditional chemical acid leaching method is abandoned, and the toxicity of waste liquid is greatly reduced; compared with a traditional high-temperature chlorination method which needs a high temperature of 1300 DEG C or above, the method adopts fluidized chlorination roasting, so that the roasting temperature is reduced by 500 DEG C, and the energy consumption is reduced by 40%; nano-bubble ultrapure water is adopted for ultrasonic cleaning, the cleaning efficiency can be improved by 50%, and residual impurities are effectively removed; through innovative design and synergistic effect of all the steps, ultra-high purity of SiO2 with the purity being greater than or equal to 99.996% is realized, and meanwhile, environmental protection, energy conservation and consumption reduction as well as industrial stable production are taken into consideration.

The present invention belongs to the technical field of polymer composite material preparation and discloses a double-layer hollow structure photonic gel film with controllable water permeation and color change, as well as its preparation method and application. The method comprises the following steps: preparing a three-dimensional PS-SiO2 photonic crystal and a three-dimensional SiO2 photonic crystal; calcining the three-dimensional PS-SiO2 photonic crystal at high temperature, filling the crystal with a polymer, and curing the crystal with ultraviolet light to obtain a hollow SiO2 structural color gel; curing the three-dimensional SiO2 photonic crystal with a polymer, and then etching the crystal with hydrofluoric acid to obtain an inverse opal gel; and bonding the hollow SiO2 structural color gel and the inverse opal gel to form a double-layer hollow structure photonic gel film with controllable water permeation and color change. The photonic gel film can be used in snowmelt warning indicators at large ski resorts, portable alcohol solubility detectors, or anti-counterfeiting identification labels for small commercial packaging.

The invention provides a preparation method of a fully-active lithium-silicon alloy negative electrode material, which comprises the following steps: (S1) adding lithium foil and silicon powder treated by hydrofluoric acid into a ball milling tank, and performing ball milling in an inert atmosphere to obtain mixed powder; (S2) pressing the mixed powder into a compact precast block; heating the precast block to 450-550 DEG C by using a smelting furnace, and keeping the temperature for 10-20 minutes, so that the lithium part is molten to wet the silicon; (S3) the temperature is increased to the reaction temperature of 680-850 DEG C, heat preservation reaction is carried out for 10-30 min, metal lithium and silicon are fully reacted, and molten alloy is obtained; and (S4) the molten alloy is sprayed to a water-cooled rotating copper roller through a quartz nozzle, the rotating speed of the rotating copper roller is 3000-5000 rpm, and the fully-active lithium-silicon alloy is obtained after cooling. The obtained lithium-silicon alloy has the characteristic of high amorphization, has extremely high ion-electron conductivity and relatively low hardness, and can relieve expansion and shrinkage of a negative electrode in a charging and discharging process, so that the rate capability and the cycling stability of a sulfide solid-state battery are improved.

The invention discloses a production method of water-resistant spherical silica gel for a catalyst carrier, and belongs to the technical field of new silica gel materials. The method comprises the following steps: taking a sodium silicate aqueous solution or alkoxy silane as a silicon source, mixing the silicon source with a template agent according to a mass ratio of 100: (1-10), adding nano silicon dioxide, and carrying out ultrasonic dispersion to obtain uniform sol; mixing the sol and a non-polar organic solvent according to a volume ratio of 1: (3-8) to form an oil-in-water emulsion, and dropwise adding a promoting solution to form microspheres with an average particle size of 400 [mu] m; mixing the microspheres with a pore expanding agent according to a mass ratio of 1: (8-15), and carrying out hydrothermal reaction to obtain a skeleton; reacting the skeleton with a silicon-based modifier according to a mass ratio of 10: (0.2-1.5); activating by hydrofluoric acid, and grafting a bifunctional coupling agent on the surface; supercritical extraction and thermal activation treatment. The specific surface area of the prepared silica gel is 492.7-533.0 m < 2 > / g, the pore volume is 0.83-1.04 cm < 3 > / g, the pore diameter is 8.2-10.9 nm, the water-resistant strength retention rate is 90.8-94.4%, the compressive strength is 10.7-12.6 MPa, the particle size variation coefficient is 3.1-4.3%, compared with traditional silica gel, the specific surface area of the silica gel is remarkably improved, and the silica gel is suitable for the field of wet catalysis.

The invention relates to a preparation method of a porous sodium-ion battery ferric phosphate sodium pyrophosphate positive electrode material, and belongs to the technical field of sodium-ion battery positive electrode materials. The method comprises the steps of precursor slurry preparation, sanding, spray drying, low-temperature heat treatment, surface activation, double-stage etching, high-temperature calcination and the like. Wherein an isopropanol-hydrofluoric acid system is adopted to perform first-stage etching on the precursor so as to open the carbon coating layer and improve the permeability of subsequent etching liquid; and then, carrying out second-stage deep etching under a heating condition by adopting a hydrofluoric acid-sodium citrate system, so as to effectively remove the silicon dioxide template and form a through type porous structure. The obtained positive electrode material has a good pore structure and a conductive network, and electrolyte infiltration and construction of a sodium ion diffusion channel are facilitated, so that the rate capability and the cycle stability of the positive electrode material are improved. The preparation method disclosed by the invention is simple and convenient in process and suitable for large-scale preparation of the high-performance sodium-ion battery positive electrode material.

The invention discloses a rinsing process for deep cleaning of purified natural quartz, which comprises the following steps: putting acid-washed quartz sand into a cleaning medium tank containing a mixed cleaning solution of deionized water and absolute ethyl alcohol for cleaning, and applying ultrasonic waves in the cleaning process; the cleaned quartz sand is put into a cleaning medium tank containing a mixed cleaning solution composed of deionized water, hydrogen peroxide and hydrofluoric acid to be cleaned, and ultrasonic waves are applied in the cleaning process; and the cleaned quartz sand is put into a cleaning medium tank containing deionized water to be rinsed so as to remove acid pickling residues to achieve deep cleaning, and ultrasonic waves are applied in the cleaning process. According to the method, a three-step cleaning scheme is innovatively adopted, so that loose impurities on the surfaces of quartz sand particles and organic reagent residues of a flotation process are efficiently stripped; the three steps are clear in function and have a synergistic effect, and the cleaning effect is far better than that of traditional single washing.

The invention provides high-transparency rare earth doped fluoride glass and a preparation method thereof, and belongs to the technical field of glass. The calcium fluoride ensures high transparency and chemical stability, the magnesium fluoride improves the ultraviolet transmittance and the mechanical strength, and the barium fluoride optimizes the melting fluidity and the rare earth doping uniformity; aluminum fluoride is added to inhibit crystallization and enhance uniformity, the rare earth element realizes optical function regulation and control, and ammonium fluoride provides a fluorine source and reduces impurities; in a preparation link, quick lime is dedusted and then reacts with pure water in proportion, impurities in a calcium nitrate solution are removed by hydrogen peroxide, uniform growth of calcium carbonate crystal nucleuses is controlled by ammonia water and carbon dioxide, and calcium fluoride is synthesized by hydrofluoric acid in proportion and dried at low temperature after plate-frame pressure filtration and purification; after the raw materials are refined through ball milling, the melting temperature is controlled in stages, impurities, reaction integrity and a microstructure are accurately controlled in the whole process, and finally the high-transparency functional glass is prepared.

The application relates to the technical field of lithium ion battery materials, and discloses a low-expansion silicon-carbon material and a preparation method thereof. The low-expansion silicon-carbon material has a porous core-shell structure, the inner core is graphene / metal-doped amorphous carbon-coated nano silicon, and the shell is boron-doped amorphous carbon. The preparation method comprises the following steps: firstly, a silicon oxide compound, a graphene oxide solution and an organic metal polymer are added into an organic carbon source solution, spray drying is carried out, and an oxidized graphene-coated metal-doped silicon oxide precursor material is obtained through reaction; secondly, a mixed gas of a boron source gas and argon is introduced into the oxidized graphene-coated metal-doped silicon oxide precursor material, and a boron-doped silicon-carbon composite material is obtained through reaction; and thirdly, the boron-doped silicon-carbon composite material is soaked in a hydrofluoric acid solution, and the low-expansion silicon-carbon material is obtained after drying. Through the technical scheme, the problems of high expansion and poor rate performance of the silicon-carbon material in the related art are solved.

The invention relates to the technical field of semiconductor cleaning agents, and particularly discloses an etching solution for SiC surface silicon and a preparation method of the etching solution. The etching solution for SiC surface silicon comprises an aqueous solution of a component A and an aqueous solution of a component B. The component A comprises the following raw materials in parts by weight: 3-8 parts of nitric acid, 1-2 parts of hydrofluoric acid, 0.5-1 part of a complexing agent and 0.1-1 part of a surfactant; the raw materials of the component B comprise modified citric acid and citric acid in a mass ratio of (2.2-5.7): (1-1.8), and the modified citric acid is obtained by modifying a dihydroxy compound. The etching solution for the SiC surface silicon has higher selectivity on the SiC substrate surface silicon and other impurities, the etching effect and the etching rate of the etching solution on the SiC surface silicon are effectively improved, the loss of the SiC substrate is reduced, and the problem of environmental pollution is also reduced.

The invention belongs to the technical field of battery electrolyte, and particularly relates to flame-retardant cyclic phosphamide eutectic electrolyte as well as a preparation method and application thereof. According to the invention, through reasonable molecular design, the flame-retardant cyclic phosphamide eutectic electrolyte is obtained. Through the design of the annular structure, a film is formed on the positive and negative electrode interface of the electrode in the battery operation process, so that the stability of the battery is improved. Phosphamide groups are introduced into the cyclic structure, hydroxyl radicals generated in the battery operation process are captured through phosphorus-oxygen bonds, and the chain reaction of combustion is blocked. Meanwhile, different designs of amino groups on phosphamide can achieve a self-cleaning effect, hydrofluoric acid and water generated in a battery circulation process are removed, and the battery is protected from electrode structure collapse caused by the hydrofluoric acid and the water in an operation process. The safety performance of the lithium battery in the cycle process is obviously improved, and the development of the lithium battery with high safety and stable operation is effectively promoted. The preparation process is simple, safe to operate, high in purity and suitable for industrialization.

The invention provides a purification method and application of a coal-based hard carbon material, belongs to the technical field of lithium / sodium ion battery negative electrode materials, and overcomes the defects that according to an existing purification method, the ash content is lower than 3%, the iron content is lower than 400 ppm, and the requirements are difficult to meet. Turning over the materials and reacting for 3.8-4.2 hours in a boiling state; acidizing: mixing an acid solution, and reacting for 2-8 hours at the temperature of 60-100 DEG C; the mixed acid solution comprises hydrochloric acid with the volume concentration of 10%-30% and hydrofluoric acid with the volume concentration of 0.5%-8%; according to the high-purity coal-based hard carbon material and the preparation method thereof, purification and deep impurity removal can be cooperated, the original coal ash content higher than 8% can be reduced to lower than 1%, and the iron content of the high-purity coal-based hard carbon material is lower than 100 ppm.

The invention relates to the technical field of material detection, and particularly discloses a method for determining content distribution of impurity elements in gradient depth of a surface layer of a quartz glass product. The method comprises the following steps: (1) putting a sample into a corrosion-resistant container in a clean environment; (2) adding 5-20wt% of hydrofluoric acid solution for etching, and collecting an extraction solution; (3) evaporating a part of the extraction solution to dryness, and adding 1-3wt% of nitric acid to dissolve residues; (4) measuring the concentration of impurity elements; (5) diluting the leaching solution, and then measuring the concentration of the silicon element; (6) performing a blank experiment; (7) calculating the etching quality and depth according to a formula; and (8) calculating the content of impurity elements in combination with the etching quality. According to the method, layer-by-layer analysis of the surface layer of the quartz glass at different depths in a range from submicron to tens of microns is realized, and the enrichment layer or diffusion gradient of impurity elements can be clearly and intuitively revealed.

A technique enabling wet etching of a first silicon oxide film with high selectivity with respect to a metal film and a second silicon oxide film is provided. A substrate processing method of wet-etching a substrate having a stacked structure including a metal film, a first silicon oxide film, and a second silicon oxide film having a moisture content lower than that of the first silicon oxide film is provided. The substrate processing method includes performing an etching while increasing etching selectivity of the first silicon oxide film with respect to the second silicon oxide film and the metal film by supplying an etching liquid, which is prepared by diluting sulfuric acid, hydrogen peroxide and hydrofluoric acid in an anhydrous organic solvent, to the substrate such that the metal film, the first silicon oxide film, and the second silicon oxide film are simultaneously exposed to the etching liquid.

The invention belongs to the field of fine chemicals and glass storage, and particularly relates to composite acid, a preparation method and a method for cleaning glass rainbow spots through the composite acid. The preparation method comprises the following steps: sequentially adding 3-5% of acetic acid, 0.1-0.2% of fatty alcohol-polyoxyethylene ether, 0.3-0.5% of disodium ethylene diamine tetraacetate, 0.5-1.5% of hydrofluoric acid, 1.5-3% of concentrated sulfuric acid and the balance of water to a proper amount of water, and uniformly mixing to obtain a composite acid; the method comprises the following steps: completely immersing glass with rainbow spots in a thermal composite acid solution, taking out the glass, cleaning the glass until no composite acid solution is left, adding calcium carbonate into waste liquid after cleaning is completed, and discharging the waste liquid after the pH value of the waste liquid is qualified. The glass cleaning agent has an efficient and comprehensive decontamination effect on glass rainbow spots, impurity ions difficult to remove are not introduced, and cleaned glass is high in light transmittance, low in haze and small in damage to a glass body.

The application relates to a preparation method of a coal-based hard carbon negative electrode material and application thereof, and belongs to the field of secondary battery material preparation. The application aims at solving the problems that the coulomb efficiency and reversible charge-discharge specific capacity of the prepared hard carbon material are low after high-temperature treatment of the existing coal-based precursor, the operation of acid washing removal is relatively complex, and the used hydrofluoric acid is relatively dangerous. The preparation method comprises the following steps: one, descaling treatment; two, micro-arc oxidation treatment; and three, carbonization. Application: the application is used for preparing a secondary ion battery negative electrode material. The application is used for the preparation of the coal-based hard carbon negative electrode material and the application thereof.

The present application is suitable for the technical field of composite materials, and provides a laminated composite material toughened intermediate layer and a preparation method thereof.The preparation method comprises the following steps: using a wet non-woven material processing method to obtain an aramid short fiber wet-laid non-woven felt; then activating the surface of the aramid fiber by hydrofluoric acid etching; grafting soluble polyether ether ketone resin with active end groups on the surface of the aramid fiber, while realizing the impregnation of the aramid fiber; and making the polyether ether ketone resin grafted on the surface of the aramid fiber crystallize again through an acidification reduction reaction.The present application regulates the interface bonding performance of the aramid toughened intermediate layer in the laminated composite material, while keeping the original crystallinity of the polyether ether ketone resin, can effectively improve the interlaminar toughness of the carbon fiber reinforced polyether ether ketone composite laminated plate, can significantly reduce the possibility of interlaminar cracking, provides a new scheme for the interlaminar toughening of this kind of material, and has potential application prospects in the field of special materials for aerospace, etc.

A wiring board manufacturing method including a step A of forming a laser-modified portion in a glass substrate by applying laser light to the glass substrate from a first surface toward an opposite surface thereof; a step B of forming, on the first surface of the glass substrate, a first surface wiring layer including a hydrofluoric acid resistant metal film and a copper layer; a step C of etching a surface of the glass substrate opposite to the first surface to form a through via in the laser-modified portion and form a second surface of the glass substrate, the second surface being an opposite surface to the first surface; a through via treatment step D of removing an etching residue of glass adhered to the hydrofluoric acid resistant metal film; and a step E of forming a through electrode in the through via.

The invention discloses UV-cured acid-resistant glass protection ink and a preparation method thereof. The protection ink is prepared from the following components in parts by weight: 55 to 75 parts of carboxylic acid polyester acrylate, 5 to 20 parts of urethane acrylate, 10 to 30 parts of diluent, 10 to 25 parts of silicon dioxide modified photopolymerization initiator, 10 to 30 parts of filler, 0.1 to 2 parts of flatting agent and 0.1 to 2 parts of defoaming agent. According to the UV-cured acid-resistant glass protection ink and the preparation method thereof, the UV-cured acid-resistant glass protection ink is good in flexibility, high in adhesive force, capable of resisting high-concentration hydrofluoric acid, sulfuric acid and the like, good in protectiveness, easy to demould and convenient to operate, can be suitable for silk-screen printing and is mainly applied to temporary protection of cover plate glass and the like.

This invention relates to the field of glass surface treatment technology and discloses a novel AG glass preparation method based on nano-island masks. The method includes glass substrate pretreatment, PVD coating to form nano-islands, hydrofluoric acid etching, mask removal, and post-treatment. Specifically, it includes the following steps: Step 1: Glass substrate pretreatment: Clean the glass substrate to remove surface grease and contaminants; Step 2: PVD coating to form nano-islands: Place the glass substrate in a vacuum environment and use physical vapor deposition (PVD) to form uniformly distributed nano-islands on the surface of the pretreated glass substrate. The nano-islands have a size of 50-100 nanometers and a spacing of 200-500 nanometers. This novel AG glass preparation method based on nano-island masks uses nano-islands as the mask material, replacing the organic masks or random particle masks used in traditional processes. The nano-islands form a CrF₃ passivation layer in hydrofluoric acid, exhibiting higher corrosion resistance and stability, and ensuring precise control of the etching process.

The invention relates to the technical field of cerium-containing ultra-thin glass processing, in particular to a medicament for strengthening and thinning a cerium-containing ultra-thin glass cover plate and a preparation process thereof, which are used for solving the problems that the roughness is easy to increase and the surface smoothness does not reach the standard in the process of directly etching glass by traditional hydrofluoric acid, and if no strengthened glass cover plate exists, the glass cover plate cannot be thinned. The bending strength of the glass is obviously reduced, and the requirement on the bending strength cannot be met; meanwhile, hydrofluoric acid also causes direct contact harm to operators; the etching agent and the carbonization agent are used as agents to treat the cerium-containing ultra-thin glass cover plate, the etching agent can be used for etching and thinning the cerium-containing ultra-thin glass cover plate, the etching agent can react with fluoride to form a protective crystal nucleus layer, and the protective crystal nucleus layer is attached to the surface of the glass to form a protective layer; the bending performance of the cerium-containing ultra-thin glass cover plate is greatly improved, the protective layer can be thickened and strengthened through the coating formed by the carbonization agent, and the bending performance of the cerium-containing ultra-thin glass cover plate is further improved.

The invention discloses a boron-doped porous silicon-carbon composite material and a preparation method thereof.The preparation method comprises the following steps that S1, silicon dioxide, a solid carbon source and boron-containing particles are subjected to high-energy ball milling, and a mixed product A is obtained; s2, mechanically mixing the mixed product A with magnesium powder to obtain a mixed product B; s3, putting the mixed product B into a reactor, roasting for 6-9 hours at 600-1000 DEG C under an inert condition, and naturally cooling to obtain a mixed product C; and S4, sequentially carrying out acid pickling on the mixture C in dilute acid and hydrofluoric acid, then cleaning with pure water and absolute ethyl alcohol, and carrying out centrifugal drying to obtain the boron-doped porous silicon-carbon composite material. The method is simple in process and low in raw material cost, and the prepared boron-doped porous silicon-carbon composite material is high in conductivity and good in cycling stability.

The application discloses a sealing method of an ultra-thick high-low frequency metal shell, which comprises the following steps: pre-oxidation and pre-plating of raw materials, cleaning of a mold; pre-oxidation and pre-plating of the raw materials to obtain a shell, a lead wire and glass; a section of glass is assembled with the shell and the lead wire, a graphite column is sleeved on the lead wire to press the glass, and the whole is placed in a selected atmosphere to perform first sealing at 800-1200 DEG C. After the first sealing, the mold and the graphite column are removed, the sealed metal shell is treated in diluted hydrofluoric acid for dozens of seconds, a second section of glass is assembled, and the assembled shell is placed at 800-1200 DEG C to perform second sealing. The plating mode of the high-low frequency metal shell is gold plating, copper plating, nickel plating or the like. The application uses step-by-step sealing to replace conventional one-step sealing, and meets the use requirements of high insulation and voltage resistance of the metal shell; and provides technical support for mass production of other types of ultra-thick metal shells.

The invention discloses a method for detecting trace acid-insoluble substances in raw material silicon powder for polycrystalline silicon, and belongs to the technical field of detection of trace acid-insoluble substances in industrial silicon powder, and the method comprises the following steps: placing the whole crucible in a hydrochloric acid solution, and heating and pickling; washing the crucible, placing the crucible on a suction filtration device, and performing suction filtration with high-purity water; the crucible is placed in an electric heating constant-temperature drying box to be dried, and then cooling and weighing are conducted; adding an industrial silicon powder sample into a beaker, and slowly dropwise adding mixed acid of hydrofluoric acid and nitric acid along the wall of the beaker; placing the beaker on a heating plate, heating until the liquid is completely volatilized, and adding a hydrochloric acid solution to completely dissolve the solid salt; transferring the sample into a container, diluting the sample with hot water, and carrying out suction filtration on the sample in a crucible subjected to acid pickling treatment while the sample is hot; and placing the crucible in an electrothermal constant temperature drying box for drying, then placing the crucible in a dryer for cooling to room temperature, and weighing. The method can solve the problem that the trace acid-insoluble substances in the industrial silicon powder cannot be accurately detected, and can be used for detecting the trace acid-insoluble substances in the industrial silicon powder when the trace acid-insoluble substances in the industrial silicon powder are lower than 0.2%.

A method for manufacturing a glass article includes etching a surface of the glass article with an etchant solution including hydrofluoric acid to produce an etched glass article. The glass article is a high refractive index glass containing a transition metal oxide and having a refractive index of greater than or equal to about 1.6 at a wavelength of 589.3 nm. The surface has surface and subsurface defects. The etching improves the surface strength of the surface of the etched glass article by removing or rounding the surface and subsurface defects, and the etching results in deposition of transition metal fluoride. The method includes cleaning the surface of the etched glass article with a cleaning solution having a pH greater than or equal to about 10 to remove transition metal fluoride from the surface of the etched glass article.