An iron-based oxide magnetic particle powder has a narrow particle size distribution a small content of fine particles that do not contribute to magnetic recording characteristics, and a narrow coercive force distribution, to enhance magnetic recording medium density. Neutralizing an aqueous solution containing a trivalent iron ion and an ion of the metal substituting a part of the Fe sites by adding an alkali to make pH of 1.5 or more and 2.5 or less, adding a hydroxycarboxylic acid, and further neutralizing by adding an alkali to make pH of 8.0 or more and 9.0 or less are performed at 5° C. or more and 25° C. or less. A formed iron oxyhydroxide precipitate containing the substituting metal element is rinsed with water, then coated with silicon oxide, and then heated thereby providing e-type iron-based oxide magnetic particle powder. The rinsed precipitate may be subjected to a hydrothermal treatment.

A process for preparing a titanic acid salt, titanic acid, and titanium oxide having a controllable particle size and a hierarchical structure, wherein the process includes the steps of: preparing a titanium-containing peroxo-complex solution; adding a basic metal compound to the titanium-containing peroxo-complex solution to form a mixture solution; adding one of polyvinyl alcohol, hydroxypropyl methyl cellulose, and polyethylene glycol to the mixture solution to form a precursor dispersion; and subjecting the precursor dispersion to a solvothermal reaction to obtain the titanic acid salt having a hierarchical structure. The process for preparing a titanic acid salt, titanic acid, and titanium oxide having a controllable particle size and a hierarchical structure, can not only realize the regulation of morphology and particle diameter of constituent units in the hierarchical structure, but also can achieve the regulation of particle size in the hierarchical structure.

A nanoparticle cluster reduction method yields a new composition of matter including a large percentage (e.g., 75% or higher percentage) of primary nanoparticles in the new composition of matter. The particle reduction method reduces the size of nanoparticle clusters in material of the new composition of matter, allows particle reduction of specific nanoparticle cluster sizes, and allows particle reduction to primary nanoparticles. This new composition of matter can include a high permittivity and high resistivity dielectric compound. This new composition of matter, according to certain examples, has high permittivity, high resistivity, and low leakage current. In certain examples, the new composition of matter constitutes a dielectric energy storage device that is a battery with very high energy density, high operating voltage per cell, and an extended battery life cycle. An example method can include a controlled gas evolution reaction to reduce the size of nanoparticle clusters.

Novel coatings disclosed herein can be used to mitigate dust adhesion. In one embodiment, a method of making a dust repellant coating includes combining a titanium dioxide sol with colloidal silica to form a mixture. The method also includes adding solvent to the mixture, stirring the mixture for about an hour, and filtering the mixture into a solution of titanium dioxide and silica dioxide.

A coated particle having excellent thermal expansion control and electrical insulation properties includes a core of a first inorganic compound containing a metal or semimetal element P; and a shell of a second inorganic compound containing a metal or semimetal element Q. The first inorganic compound satisfies 1, and the coated particles satisfy 2 and 3. 1: |dA(T)/dT| is ≥10 ppm/°C at T1 of -200° C. to 1,200° C. A is (an a-axis lattice constant of a crystal in the first inorganic compound)/(a c-axis lattice constant of a crystal in the first inorganic compound). 2: in XPS of a surface of each of the coated particles, a ratio of a number of atoms of Q contained in the shell to a number of atoms of P contained in the core t is 45 to 300. 3: an average particle diameter of each coated particle is 0.1 to 100 .Math.m.

A method of making a titanium dioxide nanowire array includes contacting a substrate with a solvent comprising a titanium (III) precursor, an acid, and an oxidant while microwave heating the solvent, thereby forming a hydrogen titanate H2Ti2O5.H2O nanowire array. The hydrogen titanate nanowire array is annealed to form a titanium dioxide nanowire array. The substrate is seeded with titanium dioxide before starting the hydrothermal synthesis of the hydrogen titanate nanowire array. The titanium dioxide nanowire array is loaded with a platinum group metal to form an exhaust gas catalyst. The titanium dioxide nanowire array can be used to catalyze oxidation of combustion exhaust.

Provided is a flaky titanate that exhibits a high weathering resistance while at the same time having the ability to endow a coating film with a silky feeling having a shading feeling and a strong luster feeling, and a method for the production thereof suitable at least for inexpensive industrial production. The flaky titanate contains a basic organic compound wherein the content of basic functional groups thereof is not more than 2.4%, and provides a coating film having a goniospectrophotometric color measured value ΔL* of at least 150. The method for producing a flaky titanate contains a step of classifying a flaking titanate having a basic organic compound at the surface and/or in interlayer position, to bring (D90−D10)/D50 in the volume particle size distribution to 1.5 or less.

A nanoparticle cluster reduction method yields a new composition of matter including a large percentage (e.g., 75% or higher percentage) of primary nanoparticles in the new composition of matter. The particle reduction method reduces the size of nanoparticle clusters in material of the new composition of matter, allows particle reduction of specific nanoparticle cluster sizes, and allows particle reduction to primary nanoparticles. This new composition of matter can include a high permittivity and high resistivity dielectric compound. This new composition of matter, according to certain examples, has high permittivity, high resistivity, and low leakage current. In certain examples, the new composition of matter constitutes a dielectric energy storage device that is a battery with very high energy density, high operating voltage per cell, and an extended battery life cycle. An example method can include a controlled gas evolution reaction to reduce the size of nanoparticle clusters.

Disclosed herein are methods for preparing a titanate compound powder comprising titanate compound particles having a controlled particle size and/or particle size distribution. The methods include mixing at least one first inorganic compound chosen from sources of a first metal or metal oxide, at least one second inorganic compound chosen from sources of titania, and at least one binder to form a mixture; calcining the mixture to form a polycrystalline material comprising a plurality of titanate compound grains and a plurality of micro-cracks; and breaking the polycrystalline material along at least a portion of the microcracks. Also disclosed are titanate compound powders having a controlled particle size distribution, ceramic batch compositions comprising the powders, and ceramic articles prepared from the batch compositions.

The present application provides vanadium dioxide doped with Ti, or vanadium dioxide further doped with other atoms selected from the group of W, Ta, Mo, and Nb. The vanadium dioxide of the present application is excellent in moisture resistance and in which deterioration of endothermic characteristics due to moisture is suppressed.