Abstract: The present invention relates to nickel-cobalt-manganese-based compound particles which have a volume-based average secondary particle diameter (D50) of 3.0 to 25.0 ?m, wherein the volume-based average secondary particle diameter (D50) and a half value width (W) of the peak in volume-based particle size distribution of secondary particles thereof satisfy the relational formula: W?0.4×D50, and can be produced by dropping a metal salt-containing solution and an alkali solution to an alkali solution at the same time, followed by subjecting the obtained reaction solution to neutralization and precipitation reaction. The nickel-cobalt-manganese-based compound particles according to the present invention have a uniform particle size, a less content of very fine particles, a high crystallinity and a large primary particle diameter, and therefore are useful as a precursor of a positive electrode active substance used in a non-aqueous electrolyte secondary battery.

Abstract: The present invention relates to nickel-cobalt-manganese-based compound particles which have a volume-based average secondary particle diameter (D50) of 3.0 to 25.0 ?m, wherein the volume-based average secondary particle diameter (D50) and a half value width (W) of the peak in volume-based particle size distribution of secondary particles thereof satisfy the relational formula: W?0.4×D50, and can be produced by dropping a metal salt-containing solution and an alkali solution to an alkali solution at the same time, followed by subjecting the obtained reaction solution to neutralization and precipitation reaction. The nickel-cobalt-manganese-based compound particles according to the present invention have a uniform particle size, a less content of very fine particles, a high crystallinity and a large primary particle diameter, and therefore are useful as a precursor of a positive electrode active substance used in a non-aqueous electrolyte secondary battery.

Abstract: Iron composite particles for purifying soil or ground water, comprise ?-Fe and magnetite, and having a ratio of a diffraction intensity D110 of (110) plane of ?-Fe to a sum of a diffraction intensity D311 of (311) plane of magnetite and the diffraction intensity D110 (D110/(D311+D110)) of 0.30 to 0.95 as measured from X-ray diffraction spectrum of the iron composite particles, an Al content of 0.10 to 1.50% by weight and an S content of 3500 to 7000 ppm; a process for producing the iron composite particles; a purifying agent containing the iron composite particles; a process for producing the purifying agent; and a method for purifying soil or ground water.

Abstract: Iron composite particles for purifying soil or ground water, comprise ?-Fe and magnetite, and having a ratio of a diffraction intensity D110 of (110) plane of ?-Fe to a sum of a diffraction intensity D311 of (311) plane of magnetite and the diffraction intensity D110 (D110/(D311+D110)) of 0.30 to as measured from X-ray diffraction spectrum of the iron composite particles, an Al content of 0.10 to 1.50% by weight and an S content of 3500 to 7000 ppm; a process for producing the iron composite particles; a purifying agent containing the iron composite particles; a process for producing the purifying agent; and a method for purifying soil or ground water.

Abstract: A purifying agent for purifying soil or ground water which comprises a water suspension containing iron composite particles comprising ?-Fe and magnetite, and having an average particle diameter of 0.05 to 0.50 ?m, an S content of 3500 to 10000 ppm and an Al content of 0.10 to 1.50% by weight, and polyaspartic acid or a salt thereof. The purifying agent is capable of decomposing aliphatic organohalogen compounds or aromatic organohalogen compounds contained in the soil or ground water in an efficient, continuous and economical manner.

Abstract: A purifying agent for purifying soil or ground water which comprises a water suspension containing iron composite particles comprising ?-Fe and magnetite, and having an average particle diameter of 0.05 to 0.50 ?m, an S content of 3500 to 10000 ppm and an Al content of 0.10 to 1.50% by weight, and polyaspartic acid or a salt thereof. The purifying agent is capable of decomposing aliphatic organohalogen compounds or aromatic organohalogen compounds contained in the soil or ground water in an efficient, continuous and economical manner.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of ?-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of ?-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: Iron composite particles for purifying soil or ground water, comprise ?-Fe and magnetite, and having a ratio of a diffraction intensity D110 of (110) plane of ?-Fe to a sum of a diffraction intensity D311 of (311) plane of magnetite and the diffraction intensity D110 (D110/(D311+D110)) of 0.30 to 0.95 as measured from X-ray diffraction spectrum of the iron composite particles, an Al content of 0.10 to 1.50% by weight and an S content of 3500 to 7000 ppm; a process for producing the iron composite particles; a purifying agent containing the iron composite particles; a process for producing the purifying agent; and a method for purifying soil or ground water.

Abstract: A purifying agent for purifying soil or ground water which comprises a water suspension containing iron composite particles comprising ?-Fe and magnetite, and having an average particle diameter of 0.05 to 0.50 ?m, an S content of 3500 to 10000 ppm and an Al content of 0.10 to 1.50% by weight, and polyaspartic acid or a salt thereof. The purifying agent is capable of decomposing aliphatic organohalogen compounds or aromatic organohalogen compounds contained in the soil or ground water in an efficient, continuous and economical manner.

Abstract: Iron composite particles for purifying soil or ground water, comprise an iron component, at least one noble metal selected from the group consisting of ruthenium, rhodium and palladium, and carbon or aluminum, and having a noble metal content of 0.01 to 5.00% by weight and a particle diameter of 0.01 to 1.0 ?m. The iron composite particles and the purifying agent according to the present invention are capable of decomposing aliphatic organohalogen compounds such as dichloromethane, carbon tetrachloride, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, trichloroethylene, tetrachloroethylene, 1,3-dichloropropene or the like, and aromatic organohalogen compounds such as dioxins, PCB (polychlorinated biphenyl) or the like, which are contained in soil, ground water or waste water, at ordinary temperature in an efficient and economical manner.

Abstract: A purifying agent for purifying soil or ground water of the present invention comprises a water suspension containing iron composite particles comprising ?-Fe and magnetite, and having an average particle diameter of 0.05 to 0.50 ?m, an S content of 3500 to 10000 ppm and an Al content of 0.10 to 1.50% by weight, and at least one additive selected from the group consisting of polymaleic acid, salts of polymaleic acid, sodium hydrogencarbonate and sodium sulfate. The purifying agent of the present invention is capable of decomposing aliphatic organohalogen compounds or aromatic organohalogen compounds contained in soil or ground water in an efficient, continuous and economical manner.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of ?-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: The present invention relates to spindle-shaped goethite particles having an average major axial diameter of 0.05 to 0.18 &mgr;m, spindle-shaped hematite particles having an average major axial diameter of 0.05 to 0.17 &mgr;m, spindle-shaped magnetic metal particles containing iron as a main component, which exhibit an adequate coercive force, good dispersibility, good oxidation stability and excellent coercive force distribution notwithstanding the average major axial diameter thereof is as small as 0.05 to 0.15 &mgr;m, and processes for producing the respective particles. Especially, the spindle-shaped magnetic metal particles containing iron as a main component, have an average major axial diameter of 0.05 to 0.15 &mgr;m, an aspect ratio of from 5:1 to 9:1, a size distribution (standard deviation/average major axial diameter) of not more than 0.30, a crystallite size D110 of 130 to 160 Å, a Co content of from 0.

Abstract: Secondary agglomerates of magnetic metal particles for magnetic recording, have a sodium content of not more than 20 ppm and a calcium content of not more than 40 ppm, an average particle diameter of 300 to 800 &mgr;m and an upper limit of particle diameters of 2,000 &mgr;m, and comprise magnetic metal primary particles having an average major axis diameter of 0.05 to 0.25 &mgr;m.

Abstract: Spindle-shaped magnetic alloy particles containing Fe and Co as main components of the present invention have a cobalt content of 20 to 50 atm % (calculated as Co) based on whole Fe; an average major axis diameter (L) of 0.03 to 0.10 &mgr;m; a coercive force value of 159.2 to 238.7 kA/m (2,000 to 3,000 Oe); a crystallite size of 100 to 160 Å; and an activation volume (Vact) of 0.01 to 0.07E-4 &mgr;m3. A high-density magnetic recording medium produced by using such spindle-shaped magnetic alloy particles containing Fe and Co as main components, have an excellent output characteristics in a short wavelength region, a considerably reduced noise and an excellent storage stability.

Abstract: Secondary agglomerates of magnetic metal particles containing primary particles having an average major axial diameter of 0.05 to 0.25 &mgr;m, said secondary agglomerates having an average particle diameter of 300 to 800 &mgr;m, an upper limit of particle diameter of 2,000 &mgr;m and a repose angle of 38 to 45°. The secondary agglomerates exhibit not only excellent handing property due to high storage efficiency, high transport efficiency and good flowability thereof, but also excellent kneading property when kneaded with various binder resins and organic solvents in a kneader, and excellent dilution-dispersibility when diluted with an additional amount of the organic solvent, upon the production of coating-type magnetic recording media, so as to more improve a surface smoothness and squareness of a magnetic coating film obtained therefrom, and a process for producing such secondary agglomerates of magnetic metal particles for magnetic recording.

Abstract: Iron particles for purifying soil or ground water of the present invention comprise a mixed phase of &agr;-Fe phase and Fe3O4 phase, and having a BET specific surface area of 5 to 60 m2/g, an Fe content of not less than 75% by weight based on the weight of the iron particles and a sulfur content of not less than 1,000 ppm. The iron particles are capable of decomposing or insolubilizing harmful substances such as organohalogen compounds and/or heavy metals, cyanogen, etc. contained in the soil or ground water in efficient, continuous and economical manners.

Abstract: Spindle-shaped magnetic metal particles containing iron as a main component of the present invention, have an average major axis diameter (L) of 0.05 to 0.15 &mgr;m; a coercive force of 111.4 to 143.2 kA/m; a Co content of from 0.5 to less than 5 atm % based on whole Fe; a crystallite size of from 150 to less than 170 Å; a ratio of Al to Co from 1.0:1 to less than 2.0:1; a specific surface area (S) represented by the formula: S≦−160×L+65; an oxidation stability (&Dgr;&sgr;s) of saturation magnetization of not more than 5.0%; and an ignition temperature of not less than 140° C. The spindle-shaped magnetic metal particles containing iron as a main component, exhibit an adequate coercive force, and are excellent in dispersibility, oxidation stability and coercive force distribution despite fine particles, especially notwithstanding the particles have an average major axis diameter as small as 0.05 to 0.15 &mgr;m.

Abstract: Spindle-shaped magnetic metal particles containing iron as a main component of the present invention, have an average major axis diameter (L) of 0.05 to 0.15 &mgr;m; a coercive force of 111.4 to 143.2 kA/m; a Co content of from 0.5 to less than 5 atm % based on whole Fe; a crystallite size of from 150 to less than 170 Å; a ratio of Al to Co from 1.0:1 to less than 2.