11358 results about "Manganese" patented technology

The invention discloses a preparation method of preheating-welding-free extra-thick steel S355MLO for ocean engineering, and belongs to the technical field of metal materials. The steel comprises the following chemical components in percentage by mass: 0.04%-0.06% of C, 0.15%-0.50% of Si, 1.35%-1.45% of Mn, less than or equal to 0.008% of P, less than or equal to 0.003% of S, 0.012%-0.02% of Ti, less than or equal to 0.015% of Al, 0.15%-0.25% of Ni, less than or equal to 0.18% of Cu, less than or equal to 0.18% of Cr, less than or equal to 0.35% of Ceq = [C + Mn / 6 + (Cr + Mo + V) / 5 + (Ni + Cu) / 15] and the balance of Fe and inevitable impurities. The low-carbon and high-manganese component design is adopted, the S355MLO super-thick steel plate with the maximum thickness of 100 mm is produced through a continuous casting billet, the carbon equivalent Ceq is smaller than or equal to 0.35, and high strength, high toughness and high welding performance are integrated. The base metal and welding toughness of the thick steel plate produced by the TMCP process are improved through the component and inclusion regulation and control technology, the process is simple, the production cost is low, the production efficiency is high, preheating before welding can be avoided, and energy conservation and consumption reduction are achieved.

The invention discloses a production method of 420-grade preheating-free welding maritime work steel, and belongs to the technical field of metal materials. The steel comprises the following chemical components in percentage by mass: 0.04%-0.06% of C, 0.15%-0.50% of Si, 1.45%-1.55% of Mn, less than or equal to 0.008% of P, less than or equal to 0.003% of S, 0.012%-0.02% of Ti, less than or equal to 0.010% of Al, 0.15%-0.25% of Ni, 0.10%-0.18% of Cu, 0.10%-0.18% of Cr, less than or equal to 0.38% of Ceq = [C + Mn / 6 + (Cr + Mo + V) / 5 + (Ni + Cu) / 15], and the balance of Fe and inevitable impurities. A low-carbon and high-manganese component design is adopted, the S420MLO super-thick steel plate with the maximum thickness capable of reaching 100 mm is produced through a continuous casting billet, the carbon equivalent Ceq is smaller than or equal to 0.38, and high strength, high toughness and high welding performance are integrated. The base metal and welding toughness of the thick steel plate produced by the TMCP process are improved through the component and inclusion regulation and control technology, the process is simple, the production cost is low, the production efficiency is high, preheating before welding can be avoided, energy is saved, consumption is reduced, and the method is environmentally friendly.

The invention relates to a surface-modified lithium-rich manganese-based positive electrode material, a preparation method and a lithium ion battery, and the preparation method comprises the following steps: uniformly mixing a lithium-rich manganese-based precursor, a lithium source and a metal oxide required by garnet type solid electrolyte to obtain a mixture; and performing gradient temperature calcination on the mixture in an oxidizing atmosphere to obtain the surface-modified lithium-rich manganese-based positive electrode material, the surface-modified lithium-rich manganese-based positive electrode material comprises a lithium-rich manganese-based material, a disordered spinel self-protection layer coated on the surface of the lithium-rich manganese-based material, and a garnet type solid electrolyte coated on the surface of the disordered spinel self-protection layer, the gradient temperature calcination comprises the following steps: calcining at the nucleation temperature of the lithium-rich manganese-based material, and then heating to the nucleation temperature of the garnet type solid electrolyte for calcining. The lithium-rich manganese-based positive electrode material can solve the problems of low first coulombic efficiency and poor rate capability of the lithium-rich manganese-based positive electrode material in related technologies.

The invention discloses a lithium manganese iron phosphate positive electrode material with a core-shell structure, which is prepared by the following steps: mixing a manganese source, an iron source, a phosphorus source, lithium carbonate and a carbon source, grinding and drying to prepare a pre-sintered material; then carrying out gas crushing on the pre-sintered material to obtain a pre-gas crushed material, and carrying out heat preservation at the temperature of 200-600 DEG C; putting the pre-gas crushed material subjected to heat preservation into an iron salt solution for quenching reaction to obtain iron compound coated lithium manganese iron phosphate; and finally, mixing the lithium iron manganese phosphate coated with the iron compound, a lithium source, a phosphorus source and a carbon source, grinding, drying, and carrying out secondary calcination to obtain the lithium iron manganese phosphate material with the core-shell structure. During preparation of the lithium manganese iron phosphate positive electrode material, a lithium manganese iron phosphate pre-sintered body and an iron salt solution are subjected to a quenching reaction to form an iron compound coated lithium manganese iron phosphate pre-sintered body, and then the iron compound coated lithium manganese iron phosphate pre-sintered body and other raw materials of lithium iron phosphate are subjected to a secondary calcination reaction to generate the composite positive electrode material with a core-shell structure. A coating structure is formed, the reaction between manganese and electrolyte is reduced, the dissolution of manganese is inhibited, the Gingtaler effect of manganese is relieved, and the stability of the material is improved; and the material has the advantages of high energy density, high power density, excellent cycle performance and strong core-shell interface bonding force.

The invention provides a lithium iron manganese phosphate positive electrode material and a preparation method and application thereof, the lithium iron manganese phosphate positive electrode material comprises a doped type iron manganese phosphate inner core and a coating layer coating the surface of the doped type iron manganese phosphate inner core, and the coating layer is a lithium-containing carbon layer; the doped iron manganese phosphate inner core comprises doped ions, and in the particles of the doped iron manganese phosphate inner core from inside to outside, the content gradient of manganese ions and iron ions is reduced, and the content gradient of the doped ions is increased. According to the lithium manganese iron phosphate positive electrode material with the structure, a series of problems caused by poor phase structure stability, poor conductivity and Jahn-Teller effect and manganese dissolution of the material in the lithium manganese iron phosphate positive electrode material can be effectively improved; further, the conductivity of the lithium manganese iron phosphate positive electrode material and the comprehensive performance of gram volume, cycling stability and the like when the lithium manganese iron phosphate positive electrode material is applied to a battery are improved.

The invention discloses 460-grade preheating-free welding maritime work steel and a preparation method thereof, and belongs to the technical field of metal materials. The steel comprises the following chemical components in percentage by mass: 0.04 to 0.06 percent of C, 0.15 to 0.50 percent of Si, 1.75 to 1.85 percent of Mn, less than or equal to 0.008 percent of P, less than or equal to 0.003 percent of S, 0.012 to 0.02 percent of Ti, less than or equal to 0.015 percent of Al, 0.25 to 0.35 percent of Ni, 0.20 to 0.28 percent of Cu, 0.20 to 0.25 percent of Cr and the balance of Fe and inevitable impurities. A low-carbon and high-manganese component design is adopted, the S460MLO super-thick steel plate with the maximum thickness capable of reaching 100 mm is produced through a continuous casting billet, the carbon equivalent Ceq is smaller than or equal to 0.45, and high strength, high toughness and high welding performance are integrated. The base metal and welding toughness of the thick steel plate produced by the TMCP process are improved through the component and inclusion regulation and control technology, the process is simple, the production cost is low, the production efficiency is high, preheating before welding can be avoided, energy is saved, consumption is reduced, and the method is environmentally friendly.

The invention discloses a 500MPa-grade supercritical CO2 corrosion-resistant pipeline coil plate and a manufacturing method thereof, and the 500MPa-grade supercritical CO2 corrosion-resistant pipeline coil plate comprises the following chemical components: 0.05 to 0.10 percent of C, 0.6 to 0.9 percent of Si, 1.50 to 1.70 percent of Mn, less than or equal to 0.010 percent of P, less than or equal to 0.002 percent of S, 0.10 to 0.30 percent of Cr, 0.35 to 0.45 percent of Mo, 0.03 to 0.05 percent of Nb, 0.01 to 0.03 percent of Ti, 0.02 to 0.05 percent of Al, 0.20 to 0.30 percent of Co, less than or equal to 0.008 percent of N, 1.2 to 4.3 percent of Mo / Cr, 0.75 to 0.92 percent of Mo + Cr + Co, 2.8 to 3.9 percent of Si / Co and the balance of Fe and inevitable elements. The manufacturing method comprises the steps of smelting, slab continuous casting, continuous casting slab heating, rolling, cooling and coiling. In the transverse direction of the rolled plate, Rt0.5 is larger than or equal to 540 MPa, Rm is larger than or equal to 640 MPa, Rt0.5 / Rm is smaller than or equal to 0.87, A50 mm is larger than or equal to 36%,-40 DEG C impact energy KV8 is larger than or equal to 220 J, and-20 DEG C drop weight DWTT is larger than or equal to 95%; in the longitudinal direction, Rt0.5 is larger than or equal to 520 MPa, Rm is larger than or equal to 630 MPa, Rt0.5 / Rm is smaller than or equal to 0.86, and A50mm is larger than or equal to 38%; the average corrosion rate in a 14.5 MPa supercritical CO2 environment is 1t; and 0.05 mm / a. The low-carbon medium-manganese molybdenum-chromium-cobalt-containing alloy design is adopted, the low-temperature toughness of a weld joint is guaranteed, the CO2 corrosion resistance and the oxidation resistance are improved, and higher safety is achieved in pipeline engineering.

A lithium secondary battery includes a positive electrode, a negative electrode, a separator, and an electrolyte, wherein the positive electrode includes a positive electrode active material layer having a positive electrode active material containing an overlithiated manganese-based oxide represented by Formula 1 below, and the negative electrode includes a negative electrode active material layer having a silicon-based negative electrode active materialLiaNibCocMndMeO2  [Formula 1]wherein, M is at least one selected from the group consisting of Al, B, Co, W, Mg, V, Ti, Zn, Ga, In, Ru, Nb, Sn, Sr, and Zr, and 1≤a, 0≤b≤0.5, 0≤c≤0.1, 0.5≤d<1.0, and 0≤e≤0.2, and. Preferably, in the Formula 1, 1.1≤a≤1.5, 0.1≤b≤0.4, 0≤c≤0.05, 0.5≤d≤0.80, and 0≤e≤0.1.

The invention discloses a non-contact magnetoelectric composite current sensor with magnetism gathering and magnetic shielding. A sensor core is composed of a magnetoelectric sensing element, a magnetofluid layer, a magnetism gathering structure and a magnetic shielding layer. The magnetoelectric sensing element is made of manganese-doped lead magnesium niobate and amorphous alloy film composite materials, the outer side of the sensing element is coated with a magnetofluid layer made of soft magnetic composite materials, the magnetism gathering structure is made of permalloy materials with high magnetic conductivity and is divided into an upper part and a lower part, the upper part accommodates the sensing element and the magnetofluid layer, and the lower part accommodates the magnetic gathering structure. And the lower part is provided with a standardized groove for placing a conductor to be tested. The outermost layer is a magnetic shielding layer composed of multiple layers of nanocrystalline alloy strips, the vertical split type design is also adopted, and it is ensured that the magnetic shielding layer is tightly matched with the magnetic gathering structure through precision machining. The upper magnetic shielding layer and the lower magnetic shielding layer are detachably connected, and field installation is facilitated. The overall structure is compact, a circuit does not need to be disconnected during installation, and the device is especially suitable for on-line current monitoring requirements in the fields of smart grids, industrial automation and the like.

Disclosed are a flux-cored welding strip and a welding flux used in combination for submerged arc welding of a duplex stainless steel, and preparation methods and use thereof. The flux-cored welding strip is composed of a stainless steel shell and a flux core powder, the flux core powder consisting of the following components: in percentages by mass, ferrochrome nitride: 0.70% to 1.0%, a chromium powder: 26% to 27%, a nickel powder: 4.5% to 5.5%, a molybdenum powder: 3.7% to 4.2%, a manganese powder: 2.55% to 2.65%, a copper powder: 1.45% to 1.55%, a ferrosilicon powder: 1.1% to 1.2%, a tungsten powder: 1.0% to 1.15%, a niobium powder: 0.25% to 0.35%, an aluminum powder: 0.35% to 0.55%, a rhenium powder: 0.35% to 0.40%, a lanthanum powder: 0.1% to 0.15%, and a balance being an iron powder.

A solid electrolyte includes: LiaAbEc(SO4)dJeXfHh, A is selected from alkaline earth metals and alkali metals other than Li, E is selected from Al, Ga, In, Sc, Y, Ti, Zr, Hf, and lanthanides, J is selected from OH, BO2, BO3, BO4, B3O6, B4O7, CO3, NO3, AlO2, SiO3, SiO4, Si2O7, Si3O9, Si4O11, Si6O18, PO3, PO4, P2O7, P3O10, SO3, SO5, S2O3, S2O4, S2O5, S2O6, S2O7, S2O8, BF4, PF6, BOB, (COO)2, N, AlCl4, CF3SO3, CH3COO, CF3COO, OOC—(CH2)2—COO, OOC—CH2—COO, OOC—CH(OH)—CH(OH)—COO, OOC—CH(OH)—CH2—COO, C6H5SO3, OOC—CH═CH—COO, OOC—CH═CH—COO, C(OH)(CH2COOH)2COO, AsO4, BiO4, CrO4, MnO4, PtF6, PtCl6, PtBr6, PtI6, SbO4, SeO4, TeO4, HCOO, and O, X is selected from F, Cl, Br, and I, 0.5≤a<6, 0≤b<6,0<c<2,0.1<d≤6.0, 0<e≤6.0, 0<f≤6.1, and 0≤h≤0.2, and a peak is observed at a diffraction angle 2θ=22.3°±1.0° in an X-ray diffraction pattern in which Cu-Kα is used as a line source.

The invention discloses a method for homogenizing a microstructure of a low-temperature high manganese steel welding heat affected zone by using pulse current, and belongs to the technical field of welding and postweld heat treatment of high manganese steel for liquefied natural gas (LNG) storage and transportation. The treatment method comprises the following steps: (1) sampling a heat affected zone of the low-temperature high-manganese steel welded joint with microstructure gradient distribution; (2) the low-temperature high manganese steel welding heat affected zone sample is subjected to pulse current treatment at the room temperature, the pulse frequency ranges from 0.6 kHz to 6 kHz, the pulse width ranges from 0.2 ms to 6 ms, the current density ranges from 20 A / mm < 2 > to 200 A / mm < 2 >, and the treatment time ranges from 5 min to 120 min; and (3) grinding and polishing the sample, observing and analyzing the element distribution state in the heat affected zone, and quantitatively representing the grain boundary structure characteristics. According to the method, atomic diffusion, dislocation slippage and grain boundary migration of the low-temperature high-manganese steel welding heat affected zone can be promoted by applying the pulse current, redistribution of segregated atoms and dislocations in grains and at grain boundaries is rapidly achieved, and then the purposes of improving the microstructure uniformity of the low-temperature high-manganese steel welding heat affected zone and improving the impact toughness of the low-temperature high-manganese steel welding heat affected zone are achieved. The method is easy to operate, short in treatment time, environmentally friendly and particularly suitable for postweld treatment of low-temperature high manganese steel parts.

The invention provides a titanium-doped high-nickel ternary positive electrode material and a preparation method thereof. The titanium-doped high-nickel ternary positive electrode material comprises a high-nickel ternary positive electrode material and a titanium-doped element, and the content of the titanium-doped element accounts for 0.5-5wt% of the titanium-doped high-nickel ternary positive electrode material. The preparation method comprises the following steps: preparing a nickel-cobalt-manganese hydroxide precursor; uniformly mixing the nickel-cobalt-manganese hydroxide precursor with a lithium source, sintering and cooling to obtain a high-nickel ternary positive electrode material; and mixing and sintering the high-nickel ternary positive electrode material and a reducing titanium source to obtain the titanium-doped high-nickel ternary positive electrode material. Reducing titanium is used for modifying the high-nickel ternary material, more stable Ni < 2 + > is enriched on the surface of the material through an oxidation-reduction reaction to serve as a protective layer, corrosion of electrolyte to the material is reduced, and the surface stability of the material is improved; the titanium element can enter material crystal lattices more easily compared with a common doping method; the lattice structure strength of the material is improved through a relatively strong Ti-O bond, and excellent cycling stability and rate capability are obtained.

A lithium supplement additive, a positive electrode sheet, a battery, and an electric device. The lithium supplement additive comprises: a first lithium supplement agent, wherein the first lithium supplement agent comprises a first core, and the first core satisfies a chemical formula LiaMbOc, wherein a is 1.5-6, b is 0-2, c is 1-6, and the element M comprises at least one of a magnesium element, a calcium element, a vanadium element, a chromium element, a manganese element, an iron element, a cobalt element, a nickel element, a copper element, a zinc element, a niobium element, a molybdenum element, a ruthenium element, a tin element, a silicon element, a carbon element and a boron element; and a second lithium supplement agent, wherein the second lithium supplement agent comprises a second core, and the second core satisfies a chemical formula LidCeOf, wherein d is 1.5-6, e is 3-5, and f is 1.5-6. The mass fraction of the first lithium supplement agent in the lithium supplement additive is m1, the mass fraction of the second lithium supplement agent in the lithium supplement additive is m2, and m1:m2 is smaller than or equal to (10:1).

The invention relates to the technical field of filling materials, and particularly discloses an ardealite-based high-strength anti-seepage filling material and a preparation process thereof, the ardealite-based high-strength anti-seepage filling material comprises 50%-65% of pretreated ardealite, 15%-25% of Portland cement, 5%-15% of superfine slag powder, 5%-10% of electrolytic manganese residues, 5%-8% of silica fume, 3%-6% of metakaolin, 2%-4% of a composite alkali activator and 0.5%-1.2% of a polycarboxylic acid water reducer, 0.3%-0.8% of an organic silicon water repellent and 0.05%-0.1% of cellulose ether; according to the invention, through chemical reaction of Mn < 2 + > in the electrolytic manganese residue and SO4 < 2-> in the phosphogypsum, micron-sized manganite crystals (MnAl2 (SO4) 4. 22H2O) are generated to actively fill internal micro-cracks of the material, so that a filling body is endowed with a self-repairing function and the impermeability is improved, and a composite alkali activator composed of NaOH and water glass is used for synergistically activating potential gelling activity of the superfine slag powder and the silica fume, so that the self-repairing filling material is prepared. And the formation of hydration products is accelerated, and 0.3-0.5 T of pulsed magnetic field is applied in the stirring process, so that the manganite crystals are guided to orderly grow along the expected stress direction of the filling body, and the compressive strength is improved.

The invention provides a manganese-based composite positive electrode material and a preparation method and application thereof. The manganese-based composite positive electrode material has a core-shell structure; the core of the core-shell structure is made of a lithium manganate material, and the shell is made of a lithium-rich manganese-based positive electrode material. Compared with the prior art, a manganese-based composite positive electrode material precursor with the inner core mainly comprising manganese and the outer shell mainly comprising nickel, cobalt and manganese is prepared in situ by adopting a coprecipitation method, and then pre-oxidation, lithium mixing and sintering modification are performed; the high-capacity, high-safety, long-circulation and high-compaction manganese-based composite positive electrode material of which the core is the lithium manganate material and the shell is the lithium-rich manganese-based positive electrode material is obtained, so that the problems of cycling stability and high-temperature storage of the manganese-based positive electrode material are solved; furthermore, the manganese-based composite positive electrode material is used as the positive electrode material of the lithium ion battery, so that the lithium ion battery with high energy density, long service life and high safety can be prepared.

The invention relates to a Bayesian optimization-based ruthenium, tin and indium doped lithium-rich manganese-based electrocatalyst screening method, electronic equipment and a storage medium, and the method comprises the following steps: generating a uniform ruthenium, tin and indium doped lithium-rich manganese-based material data set based on Dirac distribution, and generating a doped structure through element replacement; calculating hydroxyl adsorption energy and extracting descriptors to construct a data set to train a machine learning model; performing cell expansion operation on the initial electrocatalyst structure, predicting hydroxyl adsorption energy of each adsorption site, and mapping adsorption energy deviation into current density characterization component activity in combination with Boltzmann distribution; selecting an initial component based on the obtained component activity information, and constructing an agent model by utilizing Bayesian optimization; and determining a to-be-sampled component through an expectation improvement strategy, sampling and updating the agent model, and outputting an optimal doping proportion. Compared with the prior art, the method has the advantages that the ruthenium, tin and indium doped lithium-rich manganese-based electrocatalyst with excellent catalytic performance can be efficiently screened out, and the experiment cost is reduced.

The invention relates to the technical field of high-entropy oxide and electrocatalyst synthesis, in particular to a double-phase hollow high-entropy oxide catalyst and a preparation method and application thereof, the double-phase hollow high-entropy oxide catalyst comprises metal elements and non-metal elements, the metal elements comprise ruthenium, nickel, cobalt, iron, manganese and chromium; the non-metallic element is oxygen; the chemical formula of the double-phase hollow high-entropy oxide catalyst is NiCoFeMnCrRuO. The invention further discloses a preparation method of the catalyst. The double-phase hollow high-entropy oxide catalyst has a multi-shell hollow structure, provides a larger specific surface area and exposes a large number of reaction active sites, so that the double-phase hollow high-entropy oxide catalyst has lower overpotential, higher reaction efficiency and good electrochemical stability; meanwhile, the preparation method of the double-phase hollow high-entropy oxide catalyst is simple in process, low in cost, high in repeatability and suitable for industrial mass production, and has a wide application prospect.

A double cold rolled non-oriented electrical steel sheet having a composition including: 0.0001%≤Carbon≤0.007%, 0.1%≤Manganese≤0.2%, 3.1%≤Silicon≤3.6%, 0.8%≤Aluminum≤1.1%, Phosphorus≤0.15%, Sulfur≤0.006%, Nitrogen≤0.09%, and can contain various optional elements. The remainder composition being iron and unavoidable impurities caused by processing, the microstructure is made of ferrite and has in area fraction, 80% to 100% recrystallized microstructure, 0% to 20% non-recrystallized microstructure wherein the average grain size of recrystallized microstructure is from 20 microns to 110 microns and having a percentage of eddy current losses in total iron losses, measured at 1 T and 400 Hz according to IEC 60404-2 standards, is from 35% to 45% when calculated in accordance of Bertotti method and simultaneously having a magnetic polarization at 5000 A / m (J50) from 1.64 T to 1.66 T.

The invention discloses an electricity meter terminal temperature anomaly identification method, system and device and a storage medium, and relates to the technical field of intelligent electricity meter monitoring and anomaly detection.The method comprises the steps that currents of a live line loop and a zero line loop of an intelligent electricity meter are sampled, and the deviation rate of the live line current relative to the zero line current is calculated; estimating the temperature of the terminal of the electric energy meter based on the deviation rate and by using the resistance characteristic metering error change trend of the manganese-copper shunt; and when the terminal temperature estimated value of the electric energy meter exceeds a preset threshold value, determining that the temperature of the live wire terminal is abnormal, and recording an alarm event. The method realizes real-time acquisition of current difference characteristics, provides a reliable data basis for subsequent terminal temperature estimation, realizes a method of indirectly reflecting terminal temperature rise through electrical characteristics, ensures that alarm can be triggered and a complete tracing chain can be formed when temperature abnormity occurs, and improves the accuracy of terminal temperature estimation. Therefore, the controllability of the operation safety of the electric energy meter and the completeness of post analysis are improved.

The invention provides a lithium-rich manganese-based positive electrode active material and a preparation method and application thereof. The lithium-rich manganese-based positive electrode active material comprises a lithium-rich manganese-based core, a first coating layer and a second coating layer, the chemical formula of the lithium-rich manganese-based core is Li < 1 + x > Ni Mn M < c > O < 2 + x >; 0.25 < = x < = 0.4, a + b + c = 1, 0.33 < = a < = 0.35, 0.63 < = b < = 0.65, and 0 < = c < = 0.02; m is selected from at least one of W, Ta, Nb, Ti, Sb, Al, Mg, Zr, Sr and Mo; the first coating layer is X-doped nano layered lithium cobalt oxide, and X is selected from at least two of Al, La, Nb, Sr, Ti, Mn, Mo, Ta, W, K, B and F; and the second coating layer comprises a fast ion conductor and / or a spinel-like phase cobalt lithium compound. The positive electrode active material provided by the invention has excellent storage capacity.

The invention discloses a salt leaching-extraction method for recycling lithium iron phosphate and ternary lithium battery powder through cascade circulation, and belongs to the technical field of waste lithium battery recycling. According to the method, ferric salt is adopted as a leaching agent, a circulation mechanism is constructed through iron ion valence state conversion, and cascade leaching circulation of waste lithium iron phosphate and nickel cobalt lithium manganate battery powder is achieved. A concentrated enrichment liquid containing lithium, nickel, cobalt and manganese, iron phosphate and a graphite crude product can be obtained through multiple leaching cycles. In the leaching circulation process, a mixed solvent is developed as an extraction agent of iron ions, and after extraction and hydrochloric acid reverse extraction are carried out on a leaching solution containing iron salt, the leaching agent and the extraction agent can be recycled. According to the method, the valuable metal in the waste battery powder is efficiently leached under the milder reaction condition, consumption of chemicals such as acid and alkali, a leaching agent, an oxidizing agent and an extracting agent is effectively reduced through research of a circulation mechanism, the cost is remarkably reduced, and good environmental benefits and economic benefits are achieved.

The invention provides an in-situ modified lithium-rich manganese-based precursor and a preparation method and application thereof.The preparation method comprises the following steps that a nickel-cobalt-manganese mixed metal salt solution, a precipitator solution and a complexing agent solution are introduced into a base solution for a first coprecipitation reaction, and after the first coprecipitation reaction is finished, feeding is stopped; and introducing a doped nickel-cobalt-manganese mixed metal salt solution, a precipitant solution, a complexing agent solution and a carbon source solution into a system after the first coprecipitation reaction is finished, and carrying out a second coprecipitation reaction to obtain the in-situ modified lithium-rich manganese-based precursor. According to the preparation method, doping elements and a carbon source are introduced when the lithium-rich manganese-based precursor is prepared through the coprecipitation reaction, in-situ uniform construction of oxygen vacancies and a carbon coating layer on the surface of the material is synchronously achieved, the in-situ modified lithium-rich manganese-based precursor is obtained, the treatment step of subsequent secondary coating can be reduced, the production cost can be reduced, and the method is suitable for industrial production. The technological process is shortened.

A double cold rolled non-oriented electrical steel sheet having a composition including, expressed in percentage by weight: 0.0001%≤Carbon≤0.007%, 0.15%≤Manganese≤0.3%, 3.2%≤Silicon≤3.8%, 0.8%≤Aluminum≤1.1%, Phosphorus≤0.15%, Sulfur≤0.006%, Nitrogen≤0.09%, and can contain various optional elements. The remainder composition being iron and unavoidable impurities caused by processing, the microstructure is made of ferrite and has in area fraction, 80% to 100% recrystallized microstructure, 0% to 20% non-recrystallized microstructure wherein the average grain size of recrystallized microstructure is from 20 microns to 110 microns and having a percentage of eddy current losses in total iron losses, measured at 1 T and 400 Hz according to IEC 60404-2 standards, less than 30% when calculated in accordance of Bertotti method and simultaneously having a magnetic polarization at 5000 A / m (J50) from 1.66 T to 1.69 T.

The invention relates to a high-strength stable solid waste-based composite cementing material and a preparation method and application thereof in the field of building materials. The high-strength stable solid waste-based composite cementing material is prepared from the following raw materials in parts by weight: 70-85 parts of composite solid waste micro powder; 10 to 20 parts of Portland cement clinker; 3-8 parts of a composite activator; 0.5 to 2 parts of a nano-scale function regulator; wherein the composite solid waste micro powder is prepared by mixing and grinding the following raw materials in parts by weight: 40-60 parts of blast furnace slag powder; 20 to 30 parts of fly ash; 10-20 parts of chemically modified electrolytic manganese residue powder; and 5-15 parts of steel slag powder. According to the preparation method, sodium metasilicate is adopted to assist medium-temperature calcination to chemically modify the electrolytic manganese residues, so that not only is the gelation activity of the electrolytic manganese residues effectively excited, but also free-state manganese, cadmium and other heavy metal ions in the electrolytic manganese residues are fixed in situ in newly formed zeolite-like silicate mineral lattices through thermochemical reconstruction; and a brand new technical path is opened up for safe and high-value utilization of the typical hazardous waste, namely the electrolytic manganese residues.

The invention belongs to the technical field of new energy materials, and particularly relates to a low-sulfur metal cation doped ammonium manganese ferric phosphate precursor, carbon-coated modified sodium manganese ferric pyrophosphate and a preparation method and application thereof. According to the invention, the low-sulfur metal cation doped ammonium manganese ferric phosphate precursor is successfully prepared. A proper amount of phosphoric acid source is added into the prepared metal cation doped ammonium manganese ferric phosphate precursor for treatment, so that the sulfur content of the precursor is remarkably reduced, and the molar ratio of manganese, iron, doped elements and phosphorus elements is regulated and controlled to be slightly smaller than 1. The atomic-scale distribution of elements in the precursor is realized, the tap density is also improved, and the subsequent preparation of a high-performance carbon-coated modified manganese ferric sodium phosphate pyrophosphate material is facilitated. The sodium ion battery constructed based on the material has excellent charge-discharge capacity, capacity retention ratio and cycling stability. In addition, the preparation method of the precursor is simple and convenient to operate and easy to control, and has the advantage of wide application.

The invention relates to a preparation method of a high-purity manganese target material, which belongs to the technical field of metallurgy, and comprises the following steps: firstly, drying manganese powder, then pouring the manganese powder into a graphite mold, and putting the graphite mold into a Joule hot sintering furnace for sintering, during sintering, a strategy of two-stage prepressing and four-stage gradient pressing of prepressing forming, low-pressure degassing, medium-pressure densification and high-pressure sintering is implemented, and low-temperature sintering is realized; through two-stage cooling after sintering, stress and cracking in the cooling process are avoided; by accurately controlling the temperature and time of each stage, the defects that high heating temperature and long heat preservation time are needed are overcome. The production process is integrally simplified, the internal stress is controlled to be effectively and gradually released at different temperatures, the porosity is reduced, and sintering cracking is avoided; by optimizing the sintering atmosphere of each stage, the influence of impurities such as oxygen in the air on the purity of the sintered manganese target material is avoided, and the purpose of preparing the high-purity manganese target material with low energy consumption, high efficiency and high quality is achieved.

The invention provides a manganese-silicon alloy and a production method thereof, and the production method comprises the following steps: respectively crushing a manganese-containing material, silica and coke in proportion, mixing with a dephosphorizing agent, adding a binder and a proper amount of water to prepare a premix, pressing the premix into smelted pellets, and drying; the dried smelting pellets are put into a closed electric furnace to be smelted, and alloy melt is obtained; transferring the alloy melt into a steel ladle, and blowing magnesium powder for desulfurization; the desulfurized alloy melt is subjected to slagging-off, and manganese-silicon alloy molten iron is obtained; and the manganese-silicon alloy molten iron is poured into a mold for ingot casting, and a manganese-silicon alloy finished product is obtained after cooling. According to the method, the raw materials such as the manganese material, the silica, the coke and the dephosphorizing agent are crushed respectively and then mixed, briquetted and smelted, so that the dephosphorizing and desulfurizing effects can be improved, and sulfur in the alloy can be further removed by spraying magnesium powder outside the furnace for desulfurization, so that the quality of the manganese-silicon alloy is improved.

The invention discloses a gradient composite coated modified lithium manganese iron phosphate positive electrode material and a preparation method thereof, and belongs to the technical field of positive electrode materials. An LMFP precursor is pretreated through a citric acid-ethanol mixed solution, an active crystal face is exposed, and then a three-dimensional gradient coating structure of a polydopamine (PDA) chemical bonding layer, an MXene nanosheet middle layer and a polyaniline (PANI) conductive outer layer is sequentially constructed on the surface of the material, so that the electronic conductivity of the lithium manganese iron phosphate positive electrode material is increased to 10 <-3 > S / cm magnitude, and the performance of the lithium manganese iron phosphate positive electrode material is improved. The capacity retention ratio (1C) of 500 cycles is larger than 90%, the coating layer is not prone to falling off, and meanwhile dissolution of manganese ions is effectively inhibited.

The invention provides an MHP precipitation method based on a compound alkali precipitator and application of the MHP precipitation method, and the MHP precipitation method comprises the following steps: mixing laterite-nickel ore iron and aluminum removed liquid and a compound alkali solution for precipitation reaction to obtain cobalt nickel hydroxide slurry; the compound alkali in the compound alkali solution comprises a mixture of sodium carbonate and sodium hydroxide; and carrying out post-treatment on the cobalt nickel hydroxide slurry, and separating to obtain the MHP. According to the method, a sodium hydroxide and sodium carbonate compounded system is used as a precipitator, the MHP is prepared under the cooperation of sodium carbonate and sodium hydroxide, the content of manganese in the obtained MHP is remarkably reduced, the content of nickel and cobalt in the MHP is increased, the method has important significance for reducing the cost for preparing crystals through subsequent MHP refining, meanwhile, the reaction rate is more controllable, the obtained MHP is better in filtering performance, and the method is suitable for industrial production. The water content is lower.