33 results about "Chromium trioxide" patented technology

The present disclosure relates to the synthesis of Vitamin K2 bearing varying prenyl side chains. The synthesis comprises the reaction of phenyl sulfone of tert-butyl dimethyl silyl (TBDMS) protected mono prenyl menadiol with prenyl halides bearing varying prenyl units in the presence of the phase transfer catalyst followed by reductive desulphonation to yield TBDMS ether of Vitamin K2. The TBDMS ether is then oxidized in the presence of chromium trioxide and periodic acid to yield the corresponding Vitamin K2.

The invention discloses a chromium-site high-entropy chromium lithium titanate material as well as a preparation method and application thereof, and belongs to the technical field of electrochemical energy storage materials. The crystal structure of the chromium-site high-entropy chromium lithium titanate material is a single spinel solid solution phase, and the chemical general formula of the chromium-site high-entropy chromium lithium titanate material is Li (Cr < 1-x-y-z-w > V < x > Fe < y > Mn < z > Al < w >) TiO4. According to the preparation method, chromium trioxide serves as an oxidizing agent, carbohydrate serves as a reducing agent, and rapid synthesis is achieved through a one-step combustion method. The process is simple and efficient, and the prepared chromium-site high-entropy chromium lithium titanate material has relatively high specific capacity and excellent cycling stability and can be applied as a lithium ion battery negative electrode material. According to the invention, the problems of limited theoretical capacity and poor rate capability of the existing chromium lithium titanate material are effectively solved, and a new way is provided for developing a high-performance lithium ion battery negative electrode material.

The application provides an aluminum material protection water-based paint and a preparation method thereof, and belongs to the technical field of paints. A monomer A is prepared by condensation of maleic acid through an ionic liquid, and copolymerization of hexafluorobutyl acrylate hydroxyethyl ester and butyl acrylate to obtain a polymer; a solution is prepared by stirring and mixing phosphoric acid, chromium trioxide and aluminum dihydrogen phosphate; a suspension is prepared by mixing water and magnesium oxide; the suspension is added dropwise into the solution to react, magnesium powder and the polymer are added, a dispersing agent and a leveling agent are added, and the mixture is uniformly mixed to obtain the aluminum material protection water-based paint. The aluminum material protection water-based paint prepared by the application has good corrosion resistance, good adhesion, good mechanical properties and hardness, good antibacterial, flame-retardant and high-temperature resistance, improved leveling and film-forming properties of the paint, reduced coating film defects, and a wide application prospect.

The invention discloses a magnesium oxide-containing high-performance composite crucible for smelting an aluminum-lithium alloy and a preparation method of the magnesium oxide-containing high-performance composite crucible, and belongs to the technical field of refractory materials. The preparation method comprises the following steps: mixing aluminum oxide, calcium aluminate, boehmite, magnesium oxide, chromic oxide, calcium fluoride, modified zirconium powder, aluminum oxide and a 5wt% aluminum dihydrogen phosphate solution to obtain a mixed material, and sealing and standing the mixed material to obtain a first mixed material; adding the first mixture into a mold, and carrying out static pressure treatment to obtain a blank; and carrying out gradient sintering on the green body to obtain the magnesium oxide-containing high-performance composite crucible. According to the prepared high-performance composite crucible containing magnesium oxide, the synergistic effect of the modified zirconium powder and various functional oxides is taken as a core, and a unique process is combined, so that the corrosion resistance is improved, and the problem of material deterioration caused by high activity of lithium element is solved.

The invention discloses a ferrochrome liquid decarburization method based on partial roasting and step-by-step vacuum, and belongs to the technical field of ferroalloy smelting. During operation, only part of ferrochrome raw materials and powder need to be ground into powder and roasted into the endogenous oxidizing agent mainly comprising chromic oxide; then, in a vacuum induction furnace, the blocky ferrochrome and part of the oxidizing agent are molten to form a liquid molten pool, the oxidizing agent reacts with carbon in the melt through the process of combining step-by-step stepped vacuumizing and adding of the remaining oxidizing agent in batches, generated CO is rapidly pumped away by a vacuum system, and therefore deep decarburization is achieved. The method effectively solves the technical bottlenecks that a traditional oxygen blowing method cannot produce micro-carbon ferrochrome, and a vacuum solid-state method is tedious in raw material treatment and too long in decarburization period.

The invention discloses a light conversion material, an eye-protection screen protection film and a preparation method of the eye-protection screen protection film, and relates to the technical field of nano luminescent materials. The inorganic metal oxide or the inorganic non-metal oxide and the quantum dots are connected through a cross-linking material, and the inorganic metal oxide or the inorganic non-metal oxide is selected from nano silicon oxide, nano aluminum oxide, nano zinc oxide, nano zirconium oxide, nano calcium oxide, nano sodium oxide, nano manganese heptoxide or nano chromium trioxide; the particle size of the inorganic metal oxide or the inorganic non-metal oxide is 2-100 nm; the cross-linking material is selected from a silane coupling agent or a bifunctional ligand. The light conversion material and the eye protection screen protection film provided by the invention can prolong the service life of the nano luminescent material and maintain the stability of the light conversion efficiency of the light conversion material after long-term use.

This invention provides a phosphate-based adhesive and its preparation method, belonging to the field of inorganic adhesives. The invention involves mixing a phosphoric acid solution with an aluminum source for an acid-base neutralization reaction to obtain a neutralized product; mixing the neutralized product with a trivalent metal halide for a metathesis reaction to obtain the phosphate-based adhesive; and providing a curing agent to obtain the phosphate-based adhesive. This invention incorporates heteroions into the aluminum phosphate adhesive system in the form of trivalent metal halides, eliminating the need for a reduction reaction and allowing direct use of the trivalent metal. The preparation method is simple, efficient, and easily scalable for industrial production. Furthermore, this invention limits the trivalent metal halide to one or more of chromium halides, iron halides, scandium halides, iridium halides, lanthanum halides, ruthenium halides, osmium halides, gallium halides, and molybdenum halides, expanding the range of heteroions and eliminating the need for highly toxic chromium trioxide, thus improving the safety of the preparation method.

This invention provides a refractory ceramic matrix material for smelting furnace linings and its preparation method, belonging to the technical field of ceramic refractory materials. The material includes coated modified fused magnesia aggregate, ceramic sand aggregate, surface-coated magnesia fine powder, γ-phase alumina micropowder, aluminum dihydrogen phosphate solution, alkaline silica sol, pre-reacted spinel precursor, and zirconium boride micropowder. The coated modified fused magnesia aggregate is prepared by mixing fused magnesia, silicon carbide composite powder, chromium trioxide powder, and phenolic resin powder, followed by sintering. Silicon carbide powder and magnesia powder are mixed, and a silicon nitride layer is deposited on the particle surface to obtain silicon carbide composite powder. The surface-coated magnesia fine powder is magnesia fine powder with alumina coated on the particle surface. The pre-reacted spinel precursor is prepared by preparing a mixed salt solution of magnesium nitrate hexahydrate and aluminum nitrate nonahydrate with deionized water, reacting, aging, and heat-treating. The ceramic sand aggregate is made of zirconium oxide. The allocation and use of each layer achieves a balanced improvement in performance.

This invention discloses a ceramic clay composition, ceramics, and their applications, relating to the field of ceramic technology. The ceramics of this invention are obtained by sequentially processing the ceramic clay composition through a process of material conditioning, sieving, casting, air drying, oven drying, and sintering. The introduction of specific proportions of ceramic waste A and B, modified particles with a gallium-coated cuprous oxide core and an alumina shell, and high-entropy oxide solid solutions generated from the reaction of hafnium dioxide, tantalum pentoxide, niobium pentoxide, titanium dioxide, zirconium dioxide, chromium trioxide, and carbon powder, as well as chromium heptacarbonide, into the ceramic clay composition gives the ceramics prepared from the ceramic waste excellent fracture toughness, flexural strength, wear resistance, high-temperature resistance, and self-healing ability. Therefore, this invention has broad application prospects.

The application discloses a method for separating vanadium and chromium elements from vanadium slag, which comprises the following steps: (1) roasting the vanadium slag with sodium carbonate, mixing and roasting the vanadium slag and the sodium carbonate at a certain temperature to convert vanadium and chromium elements in different valence states in the vanadium slag into the highest valence state; (2) low-temperature leaching, leaching the roasting product obtained in the first step with calcium salt and water at low temperature to obtain a calcium chromate crude liquid and a calcium vanadate leaching residue; (3) acid leaching and vanadium precipitation, separating residual chromium in the calcium vanadate leaching residue to obtain a vanadium-containing filter cake; (4) preparing vanadium pentoxide, adding water to the filter cake obtained in the third step, adding NaOH and (NH4)2SO4 to adjust the pH, and then performing water bath heating to obtain polyvanadic acid ammonium precipitate, which is dried and calcined to obtain V2O5 powder; and (5) preparing chromium trioxide, adjusting the pH of the chromium solution obtained in the second step, adding Na2SO3, reducing Cr 6+ to Cr 3+ , combining Cr 3+ with OH ‑ to form Cr(OH)3 precipitate, filtering, and calcining to obtain Cr2O3.

The application relates to the field of acetonitrile preparation, and aims to solve the problems of complicated acetonitrile impurity removal process and energy consumption, and provides a production method of a catalyst for acetonitrile preparation, which comprises the following steps: S100, 25-45 parts of pseudo-boehmite, 10-15 parts of activated carbon, 5-7 parts of chromium trioxide and 2-8 parts of P123 are mixed, then aging is carried out at 30-55 DEG C for 3-8 h, granulation is carried out to obtain a preform, and the particle size of the preform is 50-80 nm; S200, the preform is sintered at 500-550 DEG C for 2-4 h and sintered at 1100-1200 DEG C for 6-8 h to obtain a carrier; S300, 100-150 parts of the carrier, 1-3 parts of a noble metal precursor, 12-18 parts of chitosan and 600-800 parts of deionized water are mixed to obtain a mixed solution, the mixed solution is heated to reflux at 100-130 DEG C for 5-8 h under stirring, and then evaporative drying is carried out at 115-135 DEG C for 0.5-2 h to obtain the catalyst. The catalyst provided by the application can effectively inhibit the occurrence of a side reaction, reduce the ammonia gas consumption, and also can utilize the hydrophilic property of the catalyst to make the removal of an impurity layer, such as a carbon deposition layer, on the surface of the catalyst more simple during catalyst regeneration.

The application relates to the technical field of acid etching agents, and discloses a hydrofluoric acid acid etching agent and a preparation method thereof, wherein the hydrofluoric acid acid etching agent comprises the following components in parts by weight: 70-75 parts of hydrofluoric acid, 40-45 parts of carrageenan, 25-30 parts of a humectant, 35-40 parts of chromium trioxide and 125-130 parts of water. Through the technical scheme, the problems of easy oxidation, complex raw materials, complicated preparation process and low stability of the acid etching agent in the prior art are solved.

The invention discloses a method for preparing a sodium sulfate solution and chromic oxide of different grades from chromium-containing sodium hydrogen sulfate, which comprises the following steps: calcining the chromium-containing sodium hydrogen sulfate at high temperature to obtain a solid product and a gas product; putting the solid product into a pulping tank, adding water, pulping and dissolving until the solid product is completely dispersed, preparing a feed liquid, and carrying out filter pressing to obtain a primary filter-pressed filter cake and an acidic solution; adding alkali into the acidic solution for neutralization, preserving heat and curing, and then carrying out filter pressing to obtain a secondary filter-pressed filter cake and a slightly acidic solution; washing and filter-pressing the primary filter-pressed filter cake, and calcining to obtain low-grade chromium sesquioxide; and washing the secondary filter-pressed filter cake, carrying out filter pressing, and calcining to obtain the high-grade chromium sesquioxide. The invention provides the method for efficiently recycling the by-product chromium-containing sodium hydrogen sulfate in the production process of chromic anhydride, the problem of poison of wastes is solved, the process is simple and easy to operate, environmental protection benefits and economic benefits are considered, and the method is suitable for industrial production.

The application provides a metallographic structure display method of a gold-based alloy, and the display method comprises the following steps: taking the gold-based alloy as an anode, electrolytic immersion etching the gold-based alloy in an electrolyte composed of hydrochloric acid, nitric acid and anhydrous ethanol, then cleaning the surface of the obtained gold-based alloy to obtain the gold-based alloy after electrolytic immersion etching; soaking the gold-based alloy after electrolytic immersion etching in ammonia water, then cleaning the surface of the obtained gold-based alloy, and obtaining the gold-based alloy after preliminary treatment after the surface is dried; immersing the gold-based alloy after preliminary treatment in a corrosion liquid composed of a saturated aqueous solution of chromium trioxide, hydrochloric acid and distilled water, then cleaning the surface of the obtained gold-based alloy, and completing the display of the metallographic structure of the gold-based alloy after the surface is dried, which greatly facilitates the observation of the metallographic structure of the gold-based alloy and is beneficial to obtaining the gold-based alloy product meeting the performance requirements.

The preparation method is innovated according to the pyrolytic reaction characteristics of chromium trioxide, such as a heat absorption phenomenon and an oxygen evolution phenomenon in a pyrolytic process, which bring serious negative effects on the temperature field uniformity and heat balance of a reaction site and further affect the reaction process and phase uniformity of a product; the invention particularly relates to a preparation method and application of a porous composite positive electrode material suitable for a lithium primary battery. And the metal oxide with high heat conductivity coefficient is used for promoting the temperature field uniformity of the reaction and providing a reaction interface of the pyrolytic reaction, so that the phase uniformity of the target product and the consistency of batch performance are improved. Besides, thermal oxygen desorption is a favorable condition for pore forming, the reaction condition and the phase conversion process of the reaction are controlled through a two-step roasting method, and the porous characteristic of the positive electrode material is adjusted, so that the power characteristic and the capacity exerting efficiency of the positive electrode material are further improved, and an effective material modification method and a control method for the batch stability of the material are provided.

This invention discloses a layered chromium-based cathode material for sodium-ion batteries and its preparation method, wherein the cathode material has the general formula NaCr. 1‑x M x O2, wherein M is Ti, V, Mn, Fe, Co, Ni, Mg, Zn, Ir or Cu, and 0.01≤x<0.1; the cathode material is granular with a particle size of 1-10μm, has a trigonal crystal structure, and exhibits no phase transition characteristics; the preparation process includes mixing sodium salt, chromium trioxide and metal oxide, pressing them into sheets, and then calcining them at 700-1000℃ for 8-12h in an inert atmosphere to obtain a layered chromium-based cathode material for sodium-ion batteries; this invention, by controlling the element ratio and high-temperature sintering reaction conditions, allows the precursors to diffuse into each other at high temperatures to form a continuous solid-state layered structure, thus preparing a sodium-containing trigonal layered oxide, which exhibits no phase transition characteristics during charging and discharging over a wide voltage range, has small volume changes during charging and discharging, and combines excellent electrochemical structural stability with air stability, significantly improving battery cycle life.

This invention provides a high-entropy perovskite-type high-temperature negative temperature coefficient thermistor ceramic, its preparation method, and its application, belonging to the field of perovskite semiconductor materials. This series of high-temperature negative temperature coefficient thermistors involves mixing lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, and chromium trioxide with oxides of lanthanum oxide (La), followed by wet three-dimensional vibration ball milling, powder calcination, cold isostatic pressing, and high-temperature sintering to obtain a perovskite structure (La). 0.2 Nd 0.2 Sm 0.2 Eu 0.2 A 0.2 )CrO3 thermistor material, where A is one of Pr, Tb, Dy, Ho, Er, Yb, Lu, and Y. The electrical performance parameters of the series of materials prepared in the examples were determined as follows: B 25℃ / 1500℃ =1625K~1742K, ρ 1500℃ =7.48×10 2 Ω·cm~7.75×10 2 The material exhibits excellent negative temperature coefficient characteristics within the temperature range of 25℃ to 1500℃ and demonstrates high-temperature aging stability. The high-entropy perovskite-type high-temperature negative temperature coefficient thermistor ceramic of this application has an upper limit of applicable temperature up to 1500℃, high resistance-temperature linear correlation, and good consistency, making it suitable for manufacturing high-temperature thermistor components.

This invention discloses a microcrystalline glass, its preparation method, a cover glass, and an electronic device, belonging to the field of new materials. The composition of the microcrystalline glass is as follows (by mass percentage): SiO₂ 60-80%, Al₂O₃ 1-10%, Li₂O 10-18%, ZrO₂ 3-12%, Na₂O 0-5%, CaO 0-4%, P₂O₅ 1-5%, K₂O 0-3%, Cr₂O₃ 0-10%, Fe₂O₃ 0-10%, where Cr₂O₃ and Fe₂O₃ are not both 0 and 1.9wt%≤Cr₂O₃+Fe₂O₃≤10wt%, the crystalline phase contains a crystal phase that produces a gold-like effect. The crystal phase that produces the gold-like effect is chromium trioxide crystal, or iron oxide crystal, or chromite spinel, or chromium trioxide crystal and chromite spinel.

The application relates to the field of electronic materials, and particularly discloses a low-gradient zinc oxide varistor disc and a preparation method thereof; the low-gradient zinc oxide varistor disc comprises the following raw materials in parts by weight: 88-96 parts of zinc oxide, 1.5-3 parts of diantimony trioxide, 2-5 parts of bismuth trioxide, 0.2-1.8 parts of nickel oxide, 0.1-0.9 parts of cobalt trioxide, 0.1-0.4 parts of manganese oxide, 0.02-0.07 parts of chromium trioxide, 0.15-0.18 parts of lithium acetate, 1.2-1.8 parts of a dispersing agent, 1.8-2.5 parts of a binding agent, 0.12-0.15 parts of aluminum nitrate and 0.001-0.003 parts of silver nitrate; under the synergistic action of the components, the use ratio of the components is adjusted, the potential gradient of the varistor disc is reduced, the large-current resistance of the varistor disc is improved, and the change of the electrical performance after impact is reduced.

The application discloses a method for cleaning and reprocessing and resource utilization of waste chrome tanning scraps and application thereof, and belongs to the technical field of solid waste resource utilization. The method is to use a citric acid-EDTA composite cleaning agent to clean and process the leather scraps and separate chromium; a composite enzyme preparation is used to enzymatically hydrolyze the chromium-removed leather residue under high temperature and high pressure to extract collagen; the chromium-containing filtrate is alkalized, precipitated and calcined to recover chromium trioxide; and finally, the enzymatically hydrolyzed residue is blended with a thermoplastic polymer to extrude plastic fillers. The application realizes efficient recovery of chromium and efficient extraction of collagen, and the process is clean and environmentally friendly, without toxic and harmful emissions, so that full-component and high-value utilization of the waste is achieved.

The application discloses a preparation method of 10,10-dimethylanthracene for preparing 10,10-dimethylanthracene ketone, which is characterized by the following steps: taking 10,10-dimethylanthracene as raw material, and under the action of a cobalt-based catalyst and an oxygen-containing atmosphere, 10,10-dimethylanthracene ketone is prepared in one step, the conversion rate of the raw material 10,10-dimethylanthracene is greater than 85%, and the selectivity of 10,10-dimethylanthracene ketone is greater than 85%. At present, in the industry, 10,10-dimethylanthracene ketone is prepared from 10,10-dimethylanthracene through the oxidation of chromium trioxide or the bromination under light irradiation and a hydrolysis reaction, but there is a great environmental pollution problem in the reaction process. Compared with the prior art, the catalyst system of the application is cheap and easy to obtain, has high catalytic activity, is safe and environmentally friendly, and is simple in post-treatment, and therefore has great industrial application value.

The application discloses a chromium-site high-entropy lithium chromic titanate material and a preparation method and application thereof, and belongs to the technical field of electrochemical energy storage materials.The crystal structure of the chromium-site high-entropy lithium chromic titanate material is a single spinel solid solution phase, and a chemical general formula thereof is Li(Cr 1‑x‑y‑z‑w V x Fe y Mn z Al w )TiO4.The preparation method is fast synthesis by one-step combustion method with chromium trioxide as an oxidizing agent and a carbohydrate as a reducing agent.The chromium-site high-entropy lithium chromic titanate material prepared by the application has high specific capacity and excellent cycle stability, and can be applied as a lithium ion battery negative electrode material.The application effectively solves the problems of limited theoretical capacity and poor rate performance of existing lithium chromic titanate materials, and provides a new way for developing high-performance lithium ion battery negative electrode materials.

This invention discloses a method for preparing a six-element master alloy of aluminum, titanium, tin, zirconium, molybdenum, and chromium, comprising the following steps: Step S1, thoroughly mixing an appropriate amount of potassium chlorate (a heating agent) with aluminum powder, titanium dioxide, tin dioxide, zirconium dioxide, molybdenum trioxide, chromium trioxide, and a slagging agent; Step S2, loading the uniformly mixed materials into a reaction vessel, performing a compaction treatment, and then igniting the mixture. The resulting molten alloy sinks, while slag used to protect the molten alloy floats to the surface. After cooling, the molten alloy yields an initial aluminum-titanium-tin-zirconium-molybdenum-chromium alloy block; Step S3, the alloy block is refined and crushed to obtain the aluminum-titanium-tin-zirconium-molybdenum-chromium master alloy. The method for preparing the six-element master alloy of aluminum, titanium, tin, zirconium, molybdenum, and chromium provided by this invention achieves a one-time preparation through a self-propagating reaction, resulting in a more uniform alloy composition. This effectively improves the alloying degree of TC17 and Ti1000, prevents component segregation and inclusions, and enhances the performance of titanium alloys such as TC17 and Ti1000. This invention also provides an aluminum-titanium-tin-zirconium-molybdenum-chromium master alloy prepared by the above method.

The invention discloses a high-temperature curing ablation-resistant heat-insulating two-component coating and a preparation process thereof. The coating is composed of a component A and a component B, wherein the component A comprises modified epoxy resin, liquid nitrile rubber, aluminum hydroxide powder, chromium sesquioxide, high silica fiber powder, hollow glass beads, toluene and the like; and the component B comprises a curing agent and a curing accelerator. The preparation method comprises the following steps: preparing the aluminum hydroxide powder, the chromium sesquioxide, the high silica fiber powder and the hollow glass beads into filler dispersion liquid; preparing a resin-rubber mixture from epoxy resin and liquid nitrile rubber; uniformly and slowly adding the filler dispersion liquid into the resin rubber mixture under a stirring condition, soaking at room temperature under a static magnetic field condition, and grinding to obtain a component A; a curing agent and a curing accelerator are used as a component B; by optimizing the composition of the coating, the ablation resistance and the heat insulation performance can be obviously improved only by coating a single layer, the construction process is simplified, the thickness of the coating is reduced, and the high temperature resistance of the coating is improved.

The invention discloses a method for preparing a mu3-O trinuclear chromium propionic acid complex based on microchannel-microwave, and relates to the technical field of organic synthesis.The method comprises the following steps that a chromium trioxide-propionic acid aqueous solution and an n-propyl alcohol aqueous solution are fed into a microchannel reactor to be subjected to a reaction, and a microchannel reaction solution is obtained; feeding the micro-channel reaction liquid into a microwave reactor, carrying out toluene azeotropic dehydration reaction, and obtaining microwave reaction liquid after dehydration is completed; carrying out reduced pressure distillation on the microwave reaction liquid at the pressure of 30 KPa and the temperature of 77-79 DEG C until no distillate exists, crystallizing, filtering and drying to obtain a mu3-O trinuclear chromium propionic acid complex; the method for preparing the mu3-O trinuclear chromium propionic acid complex has the characteristics of high raw material conversion rate, short reaction time, good product selectivity and no need of introducing additional inorganic acid, so that the yield and purity of the target product are high, no wastewater, waste gas or waste residue is generated, and the method is safer and more environmentally friendly.

The application discloses a high-entropy rare earth chromate negative temperature coefficient thermosensitive ceramic material, a preparation method and application thereof, and belongs to the field of high-temperature thermosensitive sensors, and aims to solve the stability problem of a chromium-based perovskite in long-term use at high temperature, in particular the problem of electrical property decrease caused by Cr element volatilization. The negative temperature coefficient thermosensitive ceramic material is prepared by mixing raw materials lanthanum trioxide, neodymium trioxide, samarium trioxide, europium trioxide, gadolinium trioxide and chromium trioxide respectively with dysprosium trioxide, holmium trioxide, yttrium trioxide and erbium trioxide according to a stoichiometric ratio, and then performing wet ball milling, drying, powder calcination, cold isostatic pressing and high-temperature sintering, so that a perovskite structure (La 1 / 6 Nd 1 / 6 Sm 1 / 6 Eu 1 / 6 Gd 1 / 6 M 1 / 6 )CrO3 thermosensitive ceramic material is obtained, wherein M is Dy, Ho, Y or Er. The electrical performance parameters of the thermosensitive ceramic material are as follows: B 25℃ / 1500℃ =1927~2011 K, ρ 1500℃ =1.29×10 2 ~1.60×10 2 Ω·cm, and the thermosensitive ceramic material exhibits good high-temperature aging stability at high temperature (after aging for 500 hours at 1500 DEG C, the resistance drift rates are all less than 4.6%).

The present application belongs to the technical field of metallurgical equipment maintenance and special refractory ceramics, and discloses a magnesium-carbon brick residual thickness judgment method based on shape change and a magnesium-carbon brick structure. The magnesium-carbon brick is sequentially provided with an initial function section, a warning function section and a dangerous function section along the erosion direction of the working surface, each section adopts different geometric profiles of convex arc surface, parallel plane and concave arc surface, and chromium trioxide is added as a thermal characteristic indicator in the warning section, and boron carbide or yttrium oxide is added as a chemical characteristic indicator in the dangerous section. Through the cooperative design of geometric profile and characteristic indicator, combined with a multi-modal sensing unit, the present application realizes real-time collection, analysis and matching of the geometric and physical state of the inner wall of the furnace lining, can accurately determine the erosion stage and residual thickness grade of the magnesium-carbon brick, significantly improves the functional integration and service safety of special refractory ceramic products, and solves the problems of traditional refractory material thickness measurement, such as dependence on furnace shutdown, detection lag and insufficient precision.

The invention belongs to the technical field of glass pigments, and particularly relates to a boron-promoted sintering low-expansion black pigment and a preparation method and application thereof.The black pigment is prepared from, by weight, 1-6 parts of boron compound, 2-12 parts of metal oxide, 0-2 parts of lithium carbonate, 0-5 parts of ammonium heptamolybdate, 10-25 parts of manganese dioxide, 12-35 parts of copper oxide and 45-55 parts of chromic oxide. The preparation method comprises the following steps: weighing the raw materials according to certain parts by weight, transferring the raw materials into a mixer, and uniformly mixing the raw materials; and transferring the mixture into a muffle furnace for calcining treatment, cooling, ball-milling and crushing, and sieving. The black pigment provided by the invention is uniform in particle, the minimum thermal expansion coefficient can reach 68.8 * 10 <-7 > / DEG C, and the black pigment can be applied to household appliances, automobiles and photovoltaic glass, especially high borosilicate and microcrystalline glass.

The utility model discloses a kind of chromium trioxide discharge bin observation devices, comprising: fixed in the observation window of discharge bin reserved observation port, further comprising: a pair of fixed parts being set along the opposite two side edges of observation window;With the detachable connection of fixed part, to cover and set the protective cover of observation window surface.The utility model provides a kind of chromium trioxide discharge bin observation device, by setting the observation window sealed with discharge bin, avoid the deliquescence of chromium trioxide in bin, by setting fixed part and the detachable connection protective cover of it, can avoid the direct damage of condensed chromium trioxide falling observation window, protect it, and if protective cover can be quickly replaced damaged, do not affect the sealing property of observation window and the normal production of chromium trioxide.

This invention discloses a power-type chromium oxide, its preparation method, and its application. The method includes: S1, adding an acid solution to a dichromate solution, evaporating and crystallizing the reaction solution to obtain an evaporated chromium trioxide component; dissolving the evaporated component in water to obtain a chromium-containing solution, heating it to 80℃~200℃ and holding it at that temperature for a period of time, then cooling it to 0~20℃ at a certain cooling rate, and obtaining porous spherical chromium trioxide through low-temperature crystallization; S2, subjecting the porous spherical chromium trioxide to a first heat treatment in an oxygen environment to obtain a chromium oxide mixture powder; S3, adding the aforementioned powder to deionized water, ultrasonicating, filtering and drying the mixture, then subjecting it to a second heat treatment in an oxygen environment, and obtaining a power-type chromium oxide after cooling and grinding. The chromium oxide obtained by this invention has high power characteristics and low rate capacity characteristics, which is beneficial for the preparation of high specific energy and high power primary batteries. Furthermore, the preparation method is simple and suitable for large-scale industrial production and widespread application.