1164 results about "Brown iron oxide" patented technology

The invention provides a carbon quantum dot-ferric oxide nano composite material as well as a preparation method and application thereof. The composite material is prepared by the following steps: S1, mixing a ferrous sulfate solution with an imidazole methanol solution, and performing ultrasonic treatment to obtain a zeolite imidazate skeleton structure material containing an iron core; s2, calcining the zeolite imidazate skeleton structure material in an environment with a temperature range of 200-700 DEG C and oxygen partial pressure of 5-40% to obtain iron oxide with a complex frame structure; s3, synthesizing graphene carbon quantum dots with the size of 5-8 nm by adopting a trinitrophenol method; s4, the carbon quantum dots and ferric oxide powder are mixed and then evenly ground in a ball mill, the ball milling time is 60-240 min, the content of the added graphene carbon quantum dots is 0.5-3 wt%, and a carbon quantum dot-ferric oxide nanocomposite is obtained; according to the method, ferric oxide with a complex framework is compounded with the graphene carbon quantum dots, so that indoor VOCs can be oxidized at room temperature.

The invention discloses a high-adhesion super-hydrophobic protective coating process method and a coating. The high-adhesion super-hydrophobic protective coating process method comprises the following steps: S1, preparing magnetic nano iron oxide particles; s2, performing neodymium modification on the magnetic nano iron oxide particles to obtain ferromagnetic neodymium modified iron oxide; s3, preparing and spraying a neodymium modified iron oxide coating; s4, preparing and coating a negative charge modified polymer microsphere coating; s5, preparing and spraying a positive charge modified polymer microsphere coating; and S6, preparing and spraying a modified nano silicon dioxide super-hydrophobic coating. According to the method, neodymium-modified magnetic nanometer iron oxide serves as a first layer of the surface of a steel substrate and is sprayed and dried in a magnetic field, it is guaranteed that the neodymium-modified magnetic nanometer iron oxide is tightly adsorbed to the steel surface, a magnetic transition layer is formed, and then coatings with different charges are alternately coated through the electrostatic attraction effect; and finally, a high-adhesive-force super-hydrophobic coating is formed on the steel surface in a layer-by-layer self-assembly mode, and the problem that the adhesive force of the super-hydrophobic coating is poor is obviously solved.

The invention discloses a metal soft magnetic powder core and a preparation method thereof.The preparation method comprises the steps that cold sintering is conducted, under the ultrasonic-assisted condition, warm-pressing is conducted on mixed powder containing modified iron powder and a release agent, and a metal soft magnetic powder core green body is obtained; wherein the modified iron powder comprises iron powder and a coating layer, the surface of the iron powder is coated with the coating layer, and the coating layer comprises copper, hydrated ferric oxalate, hydrated cupric oxalate and iron oxide; and heat treatment is conducted, specifically, the metal soft magnetic powder core green body is subjected to heat treatment under the oxygen-containing condition, and the metal soft magnetic powder core is obtained. Ultrasonic assistance is introduced when the modified iron powder is subjected to cold sintering, and a mixed insulation coating layer of ferric oxide and copper oxide can be generated on the surfaces of powder particles in situ during heat treatment, so that the compactness, the strength, the resistivity and the magnetic conductivity of the magnetic core are improved while the pressing force is reduced and the pressing efficiency is improved.

The present invention relates, in general terms, to a face mask. The present invention also relates, in general terms, to composite material, iron-iron oxide compositions and their methods of fabrication thereof. In particular, the iron-iron oxide composition comprises a cashew testa extract and iron particles and / or oxide core-shell particles. The iron-iron oxide composition can be used as an anti-microbial composition.

The invention provides a production process for stably controlling adhesive force of a DP steel zinc layer. The production process comprises the following steps: step 1, setting a heating section 1, a heating section 2 and a furnace nose section in a total radiation heating annealing furnace; 2, according to the model and thickness of DP steel, target dew points of a first heating section, a second heating section and a furnace nose section are set; 3, according to the target dew points set in the first heating section, the second heating section and the furnace nose section in the step 2, water vapor is put into the protective gas for humidification, and the water vapor reacts with Si, Mn and Cr elements enriched on the surface of the steel plate to generate volatile oxides; the dew point of the annealing furnace is precisely controlled in a segmented mode, different humidification modes are adopted, and the surface state is controlled, so that surface oxide residues are reduced, cleanliness of a steel substrate is guaranteed, and the binding force of a zinc layer is improved; the iron oxide layer formed on the surface of the steel plate enters a reducing atmosphere annealing furnace containing hydrogen, the hydrogen can reduce the iron oxide layer on the surface of the steel plate to form a reduced iron layer, and the adhesive force of a zinc layer is improved.

The invention discloses a nuclear radiation resistant heat-insulating protective coating for steam pipelines and a preparation method thereof. The coating comprises a surface layer and a bottom layer; the surface layer comprises 30 to 50 parts of a surface layer base, 10 to 30 parts of pigments and fillers, 5-10 parts of metal powder, 18 to 20 parts of a curing agent and 18 to 20 parts of a diluent; the bottom layer comprises 10 to 30 parts of a bottom layer base, 30 to 50 parts of pigments and fillers, 5-10 parts of metal powder, 18 to 20 parts of a curing agent and 18 to 20 parts of a diluent; wherein the surface layer base comprises acrylic modified organic silicon resin; the bottom layer base comprises water glass; the pigments and fillers comprise enamel powder, ceramics and auxiliary fillers; the auxiliary fillers comprise one or more of mica, iron oxide, zinc titanate, fluoropolymer and borosilicate; the coating of the invention can effectively insulate and protect the steam pipeline in a high temperature and nuclear radiation environment, thereby extending the service life of the steam pipeline and improving the safety and reliability of the nuclear power plant.

The invention provides a lithium manganese iron phosphate positive electrode material and a preparation method and application thereof. The method comprises the following steps: mixing manganese metal and iron metal, heating, melting and uniformly mixing in an inert gas atmosphere, and grinding into powder; adding an ammonium salt solution, continuously adding the ground manganese-iron alloy powder under heating to form a suspension, introducing compressed air and stirring, reacting, filtering, washing, drying, crushing and grinding to obtain a manganese-iron oxide precursor, feeding the manganese-iron oxide precursor, a lithium source, a phosphorus source and doped metal elements into pure water, adding a carbon source, mixing to form a suspension, and grinding and drying to obtain the lithium-phosphorus-doped manganese-iron composite material. And carrying out carbon thermal reduction in an inert gas atmosphere, and crushing to obtain the lithium manganese iron phosphate positive electrode material. The ferromanganese oxide precursor prepared by heating the metal manganese and the metal iron to a molten state and mixing the metal manganese and the metal iron realizes uniform dispersion of the manganese and the iron at an atomic level, avoids the problems of nonuniform mixing of the manganese and the iron and dissolution of the manganese, and improves the conductivity and the electrochemical performance of the material.

The invention belongs to the technical field of environmental rock soil, and particularly relates to a preparation method of zeolite-magnetic iron oxide and application of the zeolite-magnetic iron oxide in catalyzing sodium percarbonate to repair petroleum hydrocarbon polluted soil. The specific method comprises the following steps: carrying out alkali treatment on zeolite, and then carrying out heat treatment to obtain alkali-heat combined modified zeolite; extracting an iron element in the iron-containing by-product with acid and preparing ferric hydroxide colloid; and uniformly mixing the alkali-heat combined modified zeolite with the ferric hydroxide colloid, carrying out solid-liquid separation, and then carrying out heat treatment and hydrogen reduction treatment to obtain the zeolite-magnetic iron oxide, the application specifically comprises the following steps: uniformly mixing sodium percarbonate, tween-80, silica sol and water to prepare a turbid solution A; uniformly mixing zeolite-magnetic iron oxide, organic acid, silica sol and water to prepare a turbid solution B; and uniformly mixing the turbid liquid B with the petroleum hydrocarbon polluted soil, then adding the turbid liquid A, uniformly mixing, and maintaining for 12-15 days to finish the remediation.

The present invention provides a glass sheet having soda-lime-silica glass composition with a high visible light transmittance (LtC) of at least 89% with a dominant wavelength (DW) from about 490 to 505 nanometers and purity (Pe) of no more than 1% for control thickness of 5.66 mm and methods of making the same. The glass composition comprising a low iron raw material, a total iron oxide (Fe2O3) of 0.02 to 0.06 wt. %, ferrous (FeO) from 0.006 to 0.02 wt. %, redox (FeO / Fe2O3) from about 0.30 to 0.55, Cr2O3 from about 0.3 to 10 ppm, TiO2 from about 50 to 500 ppm, SnO2 from about 10 to 500 ppm, and a critical amount from about 0.10 to 0.25 wt. % of SO3. The low content of iron oxide is achieved by the partial substitution of regular raw materials by low iron raw materials, with a complete substitution of regular dolomite by a low iron dolomite with a maximum content of 0.020 wt. % Fe2O3.

The invention relates to the technical field of metal material hot working, and discloses a hot-rolled coiled plate production process which comprises the following steps: preparing a reaction type protective agent, the high-temperature-resistant coating is prepared from the following raw materials in parts by weight: 20 to 40 parts of tetraethoxysilane, 5 to 15 parts of triethyl phosphate, 1 to 5 parts of triethyl borate, 0.5 to 2.0 parts of cerous nitrate (III) hexahydrate, 0.1 to 1.0 part of lithium acetate and 0.01 to 0.05 part of vanadyl acetylacetonate (IV). Coating the surface of a hot-rolled plate blank with the protective agent; the coated plate blank is heated in a heating furnace, so that the protective agent forms a molten-state protective layer in situ; carrying out hot rolling on the plate blank with the molten protective layer; and cooling and coiling the hot-rolled steel strip. In the whole heating and hot rolling process, the molten protective layer isolates the contact between the steel and the oxidizing atmosphere, so that the generation of oxide scales is fundamentally inhibited, the production process is simplified, and the metal yield is increased.

The invention discloses a method for improving corrosion resistance of steel, and belongs to the technical field of metal protection. The method for improving the corrosion resistance of the steel comprises the following procedures of acid pickling, rinsing, drying, reduction, hot dipping, passivation, drying and packaging. Replacing a plating assisting process in the hot dipping process with a thermal reduction process; and in the thermal reduction process, hydrogen with the volume content of 3-25% is adopted for thermal reduction. A plating assisting technology in a traditional hot dipping technology is replaced with a reduction technology, the steel obtained after acid pickling is dried and then fed into the atmosphere box, a small amount of iron oxide remaining on the surface of the steel is reduced into sponge iron in the hydrogen reduction atmosphere, the surface of the steel keeps active, and then a zinc-based or zinc alloy plating layer can be better plated; therefore, the corrosion resistance of the steel is greatly improved, and the service life is prolonged.

The invention discloses a waterborne epoxy coating for heavy corrosion prevention and a preparation method of the waterborne epoxy coating, and relates to the technical field of coatings. The waterborne epoxy resin, the waterborne epoxy curing agent, the titanium dioxide, the barium sulfate, the superfine talcum powder, the mica powder, the zinc phosphate, the aluminum tripolyphosphate, the superfine mica iron oxide, the glass flakes and the like are used as raw materials for preparing the epoxy coating. Meanwhile, the sheet structures of the superfine mica iron oxide and the glass flakes prolong the time for water and a corrosive medium to reach the surface of the base material, and sufficient dissociation time is given to phosphate. The anticorrosive paint disclosed by the invention has good flexibility and corrosion resistance.

The invention discloses a preparation method and application of a nano zero-valent iron-zeolite core-shell structure composite material, and relates to the technical field of nano zero-valent iron composite material preparation. A layer of zeolite core-shell structure is generated on the surface of the nano zero-valent iron to prevent iron oxide from being generated on the surface of nZVI to reduce the reaction activity, and meanwhile, the mass ratio of zeolite / zero-valent iron strongly affects gradual release of Fe < 2 + > in the nano zero-valent iron-zeolite core-shell structure composite material, so that iron core oxidation is slowed down, and the reaction activity of nZVI is improved. The release speed of electrons is also slowed down, the gradually released electrons form a long-time and stable activation effect on persulfate, and the degradation of trichlorophenol can be promoted. According to the preparation method and application of the nano zero-valent iron-zeolite core-shell structure composite material, the nano zero-valent iron-zeolite core-shell structure composite material can be obtained.

A raw material solution containing trivalent iron ions, or trivalent iron ions and ions of a metal element that partially substitutes Fe sites, and an alkaline aqueous solution for neutralizing the raw material solution are added to a reaction system to adjust the pH of the reaction system from 1.0 to 3.0 or lower. Hydroxycarboxylic acid is added to the obtained reaction solution and the pH of the reaction system is then neutralized from 7.0 to 10.0 or lower. The obtained precipitate of a substituent metal element-containing iron oxyhydroxide is coated with silicon oxide, followed by heating so as to form particles of ε-iron oxide in which Fe sites are partially substituted by other metal elements, and then, a slurry containing the particles is classified. The iron-based oxide magnetic powder has a particle shape close to a perfect sphere and is suitable for use in a magnetic recording medium.

The invention discloses a gas-sensitive material based on double noble metal doped holmium iron oxide and application of the gas-sensitive material to detection of hydrogen sulfide in a sulfur-containing ore body exploration environment, and relates to the technical field of gas-sensitive materials. HoFeO3 is used as a substrate material, and two elements of Au and Pt are used for doping modification of the HoFeO3 to prepare the gas sensitive material based on double noble metal doped holmium iron oxide. Au and Pt are combined to perform doping modification on HoFeO3, a synergistic effect is achieved on improving the temperature stability of the gas-sensitive material, the sensitivity of the gas-sensitive material in a high-humidity environment can be improved, in addition, due to the synergistic catalysis effect of Au and Pt, an energy barrier of H2S adsorption reaction can be remarkably reduced, surface electron transfer and reaction activity are promoted, and the sensitivity of the gas-sensitive material in a high-humidity environment is improved. Therefore, the working temperature is reduced, the response value is improved, and the method is suitable for detecting hydrogen sulfide gas in a sulfur ore body exploration environment.

The invention relates to a process for extracting iron from red mud by using hydrogen reduction and electrolysis technologies, the red mud is a by-product generated in the industrial production process of aluminum, the environmental burden caused by the by-product can be solved, the carbon emission can be reduced, and the development of a green metallurgical technology can be promoted. Comprising the following steps: conveying red mud serving as a raw material into a rotary furnace, conveying hydrogen serving as a reducing medium into the rotary furnace, enabling iron oxide in the red mud to form hydrogen reduced iron in a furnace heating state and a hydrogen reducing atmosphere, conveying the red mud containing the hydrogen reduced iron into a sulfuric acid solution, the hydrogen reduced iron is dissolved in the sulfuric acid solution to form a sulfuric acid solution containing iron ions, the sulfuric acid solution containing the iron ions serves as an electrolyte in an electrolysis device, and electrolytic pure iron formed by electrolytic deposition of the iron ions is obtained through the electrolysis device.

The invention aims to provide a device and method for extracting iron from red mud and preparing iron oxide red, and belongs to the technical field of resource utilization, hydrochloric acid is adopted to leach iron element in the red mud, and a ferric chloride solution is separated from leachate through an extraction process. And then, carrying out alkali precipitation, washing and firing to prepare the high-purity iron oxide red. By using the method disclosed by the invention, the iron resource in the red mud can be recycled, so that the dual purposes of resource utilization and environment-friendly treatment are achieved.

The invention belongs to the field of metal materials, and particularly relates to a hot-rolled pickled steel plate for an automobile chassis and a production method thereof. The steel plate is mainly suitable for manufacturing automobile chassis structural parts. The steel comprises the following chemical components: C, Si, Mn, Al, Ta, Ni, Cu, Cr, Pt and Y, P is limited to be less than or equal to 0.015%, S is limited to be less than or equal to 0.005%, N is limited to be less than or equal to 0.003%, and the balance is Fe and inevitable impurities. The yield strength of the steel plate is larger than or equal to 265 MPa, the tensile strength is larger than or equal to 378 MPa, the transverse elongation A is larger than or equal to 46%, transverse cold bending is conducted by 180 degrees, D = a, the steel plate is qualified, the surface quality is good, oxide scale stripes and chromatic aberration defects are avoided, the surface roughness Ra is 1.10-1.35 micrometers, and the steel plate has good corrosion resistance.

The invention relates to modified samarium-iron-nitrogen powder and a preparation method and application thereof, and belongs to the technical field of magnetic material preparation, the preparation method comprises the following steps: 1, mixing soluble samarium salt, iron oxide and ammonia water, and reacting to obtain a mixed solution; 2, mixing the mixed solution with an alkali metal hydroxide solution, and reacting to obtain a precursor; 3, the precursor reacts in the ammonia atmosphere, and samarium-iron-nitrogen powder is obtained; 4, a coating layer is arranged on the surface of the samarium-iron-nitrogen powder, and the modified samarium-iron-nitrogen powder is obtained. The preparation method is simple and convenient, and the prepared modified samarium-iron-nitrogen powder is high in purity, moderate in alpha-Fe content and excellent in intrinsic coercive force and can be used for manufacturing high-performance samarium-iron-nitrogen magnetic powder.

The invention relates to a water-based recoatable low-surface-energy coating for a steel structure surface and a preparation method of the water-based recoatable low-surface-energy coating, and belongs to the technical field of coating preparation. The paint is composed of the water-based silica sol, the acrylic resin, the modified anti-rust pigment and the like, the modified anti-rust pigment is prepared by dispersing mica iron oxide, aluminum triphosphate and bismuth molybdate in fluorocarbon resin and methacrylic resin, and the paint has excellent anti-rust performance. The low-surface-energy additive is prepared by mixing raw materials such as perfluoroalkyl ethanol and perfluoroalkyl acrylate, so that the coating is endowed with the characteristic of low surface energy. The preparation method comprises the following steps: mixing and dispersing the deionized water, the dispersing agent, the defoaming agent and the modified anti-rust pigment, adding the water-based silica sol, the acrylic resin, the flatting agent and the low-surface-energy auxiliary agent, and continuously stirring to finally obtain the coating. The coating has the characteristics of excellent rust resistance, low surface energy and recoatability, is suitable for coating the surface of a steel structure, and can improve the corrosion resistance and prolong the service life of the steel structure.

The invention provides a high-crystallinity modified iron oxide as well as a preparation method and application thereof, and relates to the technical field of organic solid waste treatment. The preparation method comprises the following steps: preparing a precursor MIL-88B by utilizing a hydrothermal method; the precursor MIL-88B is subjected to calcination treatment, and an iron oxide with the MIL-88B as the precursor is obtained; the temperature condition of the calcination treatment is 550-850 DEG C. The high-crystallinity modified iron oxide prepared by the preparation method improves methane production efficiency and stability, avoids competition of iron reducing bacteria, is stable in long-term operation and low in cost, and has both environmental and economic benefits.

The present invention relates to the technical field of steel slag solid waste utilization, and in particular to a method for selective extraction of calcium and secondary magnetic separation of iron from steel slag, comprising the following steps: adding a leaching agent into steel slag, controlling the leaching temperature to be 95-125℃ and the pH of a leaching system to 5.5-8, and continuously leaching calcium for 0.5-2 h; in the process of leaching the calcium or after the leaching of the calcium is finished, adding an oxidizing agent into a reaction system, and oxidizing part of the original non-magnetic ferrous oxide in the steel slag into magnetic ferroferric oxide; and performing magnetic separation on residues obtained after leaching to obtain magnetically separated powder having a total iron content of greater than 40% and tailing powder having an iron oxide content of greater than 40%. According to the method, calcium in the steel slag can be efficiently and selectively extracted, and a steel slag ore phase can be changed while the calcium is extracted, so that most of iron in the residues obtained after leaching can be enriched by magnetic separation again, thereby realizing grading and efficient utilization of calcium and iron elements in the steel slag, and improving the recycling rate of the iron.

The invention discloses a sulfur iron oxide composite denitrification filler, a preparation method and application, and relates to the technical field of sewage treatment, the sulfur iron oxide composite denitrification filler comprises sulfur powder, siderite, magnesite, magnesium oxide, metal manganese, metal aluminum, nano iron, boric sludge, magnetite and a binder; wherein the sum of the addition amounts of the metal manganese, the metal aluminum and the nano iron accounts for 8-16% of the mass of the sulfur-iron oxide composite denitrification filler. The technical problems that in the prior art, strength and abrasion resistance are insufficient, and denitrification efficiency is low are solved.

The invention relates to a multi-source iron-containing solid waste cold solid ball and a preparation method, and belongs to the technical field of solid waste treatment. The cold bonding ball comprises the following raw materials in parts by weight: 40-70 parts of iron-containing dust mud, 15-40 parts of a secondary metal material, 1-5 parts of a binder and 5-12 parts of a liquid modifier. A consolidation system with continuous and reasonable gradation is formed by utilizing pore filling of the fine-grained iron-containing dust mud and an aggregate bridging effect of the coarse-grained secondary metal material, so that the compactness and the compressive strength are improved; chloride ions in high-salinity wastewater are used for modifying raw materials, oxidation phase change of metal iron and low-valence iron oxide in a secondary metal material is promoted, a high-strength binding phase is generated, the compressive strength of the pellets is effectively improved, co-treatment of wastewater and multi-source solid waste is achieved, and under the condition that the cost of a binding agent is not additionally increased, the cost of the binding agent is reduced. And the cold consolidation strength of iron-containing solid wastes with different components is improved.

The invention provides a preparation method of a catalytic material for removing new pollutants in a complex water environment. The preparation method comprises the following steps: step 10, preparing a metal organic framework material; step 20, preparing iron oxide particles in the metal organic framework material to obtain the confined iron nano material; and step 30, vertically growing molybdenum disulfide nanosheets on the surface of the confined iron nanomaterial to obtain the catalytic material. According to the preparation method of the catalytic material for removing the new pollutants in the complex water environment, provided by the invention, the prepared catalytic material has excellent anti-interference capability in the complex water environment, and the reaction activity is improved.

The invention discloses porous chlorine dioxide slow-release preservative paper and a preparation method thereof.The porous chlorine dioxide slow-release preservative paper comprises a paper base, a porous carrier is fixed to the paper base through oxidized starch glue, and sodium chlorite, an activating agent and a stabilizing agent are loaded on the porous carrier; the porous carrier is one of aluminum oxide, titanium oxide, cobalt oxide, zinc oxide, copper oxide, iron oxide, cerium oxide, zirconium oxide, nickel oxide, manganese oxide, praseodymium oxide and lanthanum oxide with a porous structure. The slow release of chlorine dioxide can be stably and effectively realized, the release period of chlorine dioxide is prolonged, and long-acting stable sterilization and disinfection effects are realized.

The invention provides a positive electrode material, a preparation method thereof and a lithium ion battery, and belongs to the technical field of battery materials. Comprising the following steps: carrying out acid treatment on ferric oxide to obtain acid-modified ferric oxide; and mixing the acid-modified iron oxide, a second iron source, a lithium source and a phosphorus source to obtain a mixture, and then roasting the mixture to obtain the positive electrode material. By performing acid treatment on the ferric oxide, on one hand, impurities and a loose oxide layer on the surface of the ferric oxide can be removed, more active sites can be exposed, the reactivity of the ferric oxide is matched with that of the second iron source, the reaction process is carried out synergistically, and formation of a regular and uniform-size crystal structure is promoted; a foundation is laid for obtaining a positive electrode material with excellent electrochemical performance; on the other hand, the surfaces of the iron oxide particles can be regulated and controlled, so that agglomeration among the particles can be reduced when the iron oxide particles are mixed with the second iron source particles, the dispersity of the particles is improved, and the mixture forms more excellent gradation.

The invention relates to the technical field of material surface corrosion prevention, in particular to a spraying method for a heavy anti-corrosion coating of a port steel structure. The method comprises the following steps that (1) sand blasting derusting treatment is conducted on a steel structure base body, so that the cleanliness of the steel structure base body reaches the Sa2.5 level, and the roughness is controlled to range from 40 micrometers to 75 micrometers; 2) coating the treated substrate with epoxy zinc-rich primer, and doping graphene modified zinc powder accounting for 1-3% of the total mass of the primer to form a primer layer with a dry film thickness of 60-80 [mu] m; (3) after the primer layer is cured, the primer layer is coated with epoxy micaceous iron oxide intermediate paint, aluminum tripolyphosphate accounting for 2-5% of the total mass of the intermediate paint is further added into the epoxy micaceous iron oxide intermediate paint, and an intermediate paint layer with the dry film thickness being 150-200 microns is formed; 4, the middle paint layer is coated with weather-resistant finish paint, and a finish paint layer with the dry film thickness being 60-80 microns is obtained.According to the method, the adhesive force, chloride ion permeation resistance, salt fog resistance (larger than or equal to 3000 hours) and weather resistance of the coating are remarkably improved, the method is suitable for the harsh marine environment, and the service life of the steel structure can be prolonged to 20 years or above.

A nanocomposite material including iron sulfide (FeS2) nanoparticles, iron oxide (α-Fe2O3) nanoparticles, titanium dioxide (TiO2) nanoparticles, and graphitic carbon nitride (C3N4) nanosheets and a method of its preparation. The nanocomposite is used in a method of forming oxygen gas from water using an applied voltage and photoirradiation, a method of forming hydrogen gas from water using an applied voltage and photoirradiation, and a method of photodegrading organic pollutants using visible light photoirradiation.

The invention discloses a method for reducing breakage of scale on the surface of an S355-series medium-thickness plate. The method comprises the following steps that S1, a blank is prepared from 0.16%-0.18% of C, 1.2%-1.3% of Mn, smaller than or equal to 0.02% of P, smaller than or equal to 0.005% of S, 0.15%-0.25% of Si, smaller than or equal to 0.02% of Nb, smaller than or equal to 0.1% of Ni, smaller than or equal to 0.15% of Cr, smaller than or equal to 0.1% of Cu, smaller than or equal to 0.08% of Mo, smaller than or equal to 0.01% of V, smaller than or equal to 0.02% of Ti, smaller than or equal to 0.004% of Ca and the balance Fe and inevitable impurities; s2, heating is conducted, specifically, the heating temperature is 1150 + / -20 DEG C, the in-furnace time is 7.3-16 mm / min, and the staying time of a plate blank in a soaking section is longer than or equal to 20 min; and S3, rolling: rolling the blank by adopting a single-stand steckel mill, carrying out high-pressure water double-pump descaling by adopting a descaling box before rolling, then transporting the blank to the front of the rolling mill through a roller way, starting a rough rolling stage, carrying out rough rolling at the initial rolling temperature of about 1030-1050 DEG C, carrying out fine descaling on a rolled piece by adopting a rolling mill in the first and second passes of the rough rolling stage, and carrying out fine descaling on the rolled piece in the second pass of the rough rolling stage. After the rough rolling stage is completed, the thickness of the intermediate billet is 1.8 times or more than 1.8 times of the thickness of a finished product; and the initial rolling temperature in the finish rolling stage is smaller than or equal to 970 DEG C, and the rolled piece is subjected to finish descaling in the first pass and the last but one pass in the finish rolling stage.