10 results about "Maghemite" patented technology

The present disclosure relates to an α-Fe-containing rare earth-iron-based magnetic powder including: a core region containing a rare earth R and Fe, where R represents at least one selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Sm; an α-Fe-containing region located outside the core region and containing α-Fe and at least one selected from the group consisting of oxides, nitrides, and oxynitrides of the rare earth R; and an iron oxide-containing region located outside the α-Fe-containing region and containing magnetite or maghemite.

The present application relates to the technical field of mineralogy, and particularly provides a complex iron mineral distinguishing and quantifying method and an iron mineral content analysis method, which combines chemical dissolution, automatic mineralogy analysis and micro-area magnetic verification technology for the first time to realize the distinguishing and quantifying of complex iron minerals. The analysis method constitutes a closed and mutually checked analysis system, which combines acid treatment of carbonates, automatic mineralogy analysis of residual minerals, micro-area magnetic verification to correct the misjudgment of magnetic hematite, element surface scanning to check the accuracy of overall mineralogy quantification, and final calculation results, and checks the total iron content of chemical analysis to ensure the reliability of the final results and facilitate the standardized popularization and application.

This invention relates to a process for treating acidic mine wastewater (AMD). The process includes the following steps: adjusting the pH of the AMD to a range of 3 to 5; adding magnetite nanoparticles to form a slurry; and a) aerating the slurry obtained in step 3), or b) simultaneously heating and mixing the slurry obtained in step 3). The magnetite nanoparticles loaded with one or more metals and sulfate ions and precipitated metals are then separated from the slurry.

The present application relates to the field of denitration catalyst, disclose a kind of low-temperature denitration catalyst and its preparation method and application.The low-temperature denitration catalyst of the present application contains the product of magnetite and spinel manganese oxide compound, the magnetite is gamma-Fe2O3, and the spinel manganese oxide is lambda-MnO2.The low-temperature denitration catalyst of the present application is not contained V, and N2 selectivity is high, and the denitration performance is good.

The invention relates to the field of magnetic simulation, in particular to a magnetic simulation method for simulating a low-temperature oxidized geological sample, which comprises the following steps: S1, constructing a double-layer model in Cubit software; s2, setting interface exchange interaction constants corresponding to three exchange types including no exchange, weak exchange and uniform exchange for the double-layer structure; s3, hysteresis parameters under the three exchange interaction constants are calculated, and the numerical calculation result of which exchange constant is closer to the experimental result / literature result is judged; s4, constructing a complex multi-layer low-temperature oxidation model in Cubit software; s5, constructing a low-temperature oxidation process model based on the theoretical oxidation kinetics model and simulating particles with various particle sizes; s6, comparing a simulation result with a hysteresis parameter measured by an experiment; and S7, drawing a multi-particle-size micro-magnetic structure chart and a multi-particle-size hysteresis loop. According to the method, the oxidation process is refined, a double-layer core-shell structure of magnetite and maghemite can be constructed, and a particle aggregation model is established.

To provide magnetic powder having excellent responsiveness to a magnetic field, and to provide a method for producing the same.SOLUTION: An α - Fe-containing rare earth-iron-based magnetic powder including a core region containing a rare earth R (R is at least one selected from the group consisting of Y, La, Ce, Pr, Nd, Pm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Sm) and Fe, an α - Fe-containing region containing α - Fe and at least one selected from the group consisting of an oxide, a nitride, and an oxynitride of the rare earth R outside the core region, and an iron oxide-containing region containing magnetite or maghemite outside the α - Fe-containing region.SELECTED DRAWING: Figure 1

The invention relates to a high-entropy multi-principal-element magnesite oxide infrared emission material. The chemical formula of the material is (MgA1A2A3A4Ti) 2O3, a magnesium titanium ore structure is formed, A1, A2, A3 and A4 are any four metal ions of Co, Ni, Cr, Cu, Fe, Mn, Sr and Ca, the molar percentage of Mg < 2 + > and Ti < 4 + > is 15-35%, and A1, A2, A3 and A4 meet the atomic equimolar ratio; the magnesium titanium ore belongs to a trigonal system, O < 2-> ions form hexagonal closest packing, and octahedral gaps formed by hexagonal packing of oxygen ions are alternately filled with Mg < 2 + > and Ti < 4 + > ions. Meanwhile, the invention also discloses a preparation method of the material. The method is easy to operate and high in production efficiency, the obtained material has good high-temperature stability and infrared radiation capacity, the emissivity of the material is effectively improved by 0.78-16 microns, and the method is suitable for extreme scenes such as building energy saving and aerospace thermal control.

This invention provides a method for continuously manufacturing electric wire conductors in which the surface is insulated by an aggregate of stacked Maghemite microparticles that are magnetically attracted to each other by saturated magnetization. [Solution] The method involves creating a suspension in which maghemite microparticles are dispersed in an organic compound and the viscosity can be changed, continuously adsorbing the suspension onto a conductor, continuously covering the surface of the conductor with an aggregate of maghemite microparticles using the suspension, continuously saturating the magnetization of the maghemite microparticles, continuously winding up the conductor of the wire insulated with the aggregate of maghemite microparticles, creating a suspension in which an aggregate of fine crystals of an organic iron compound that precipitates ferrous oxide by thermal decomposition is dispersed in an organic compound with a high boiling point, thermally decomposing the organic iron compound, oxidizing the ferrous oxide to ferric oxide, reducing the viscosity of the suspension with an organic solvent, continuously immersing the conductor in the low-viscosity suspension, continuously vaporizing the organic solvent and organic compound from the conductor, continuously passing the conductor through a magnetic field, and continuously winding the conductor onto a bobbin.

A process for converting a hematite-containing material to a maghemite-containing material is developed. The process comprises: producing a crushed hematite-containing material by crushing the hematite-containing material utilizing a means for grinding, obtaining a hematite-containing material with a particle size in a range of 150 µm to 500 µm by sieving the crushed hematite- containing material utilizing a means for sifting, and exposing the hematite-containing material with the particle size of 150 µm to 500 µm to a microwave energy with a frequency in a range of 890 MHz to 930 MHz for an exposing time in a range of 30 seconds to 360 seconds utilizing a means for radiating a microwave beam. An exposed thickness of the hematite-containing material with the particle size of 150 µm to 500 is a range of 3 cm to 10 cm that has a particular effect on phase changing of the hematite to the maghemite.

This invention discloses a system, technology, and material composition for correcting eye condition. The system includes a processing device and an etching device. The processing device includes a pattern correction module configured to provide a selected two-dimensional pattern based on visually non-permanent input data instructing a user, and configured to generate operating instructions to form the selected two-dimensional pattern on the surface of the cornea via the etching device. The etching device is configured to etch the selected pattern onto the surface of a user's cornea. The material composition includes an aqueous solution containing a plurality of nanoparticles, the nanoparticles comprising magnetite nanoparticles encapsulated by biocompatible protein chains. The material composition can be used as eye drops, thereby allowing the nanoparticles to occupy the etched area on the cornea, thus maintaining the correction of eye condition.