A nanocrystal-sized cerium-zirconium-aluminum mixed oxide material includes at least 20% by mass zirconium oxide; between 5% to 55% by mass cerium oxide; between 5% to 60% by mass aluminum oxide; and a total of 25% or less by mass of at least one oxide of a rare earth metal selected from the group of lanthanum, neodymium, praseodymium, or yttrium. The nanocrystal-sized cerium-zirconium-aluminum mixed oxide exhibits hierarchically ordered aggregates having a dso particle size less than 1.5 μm, and retains at least 80% of surface area and pore volume after ageing at temperature higher than 1000° C. for at least 6 hours. The nanocrystal-sized cerium-zirconium-aluminum mixed oxide material is prepared using a co-precipitation method followed by milling the dried and calcined oxide material. The nanocrystal-sized cerium-zirconium-aluminum mixed oxide material forms a particulate filter that may be used in an exhaust system arising from a gas or diesel engine

Rare earth compound particles are prepared by a step of heating an aqueous solution containing rare earth metal ions and urea to form a rare earth compound by a reaction of a hydrolysis product of urea, and the rare earth metal ions. In the heating step, heating the aqueous solution into which an acetylene glycol-ethylene oxide adduct is added.

Decontamination compositions useful to decontaminate potentially toxic materials, such as PAH and others, present on clothing comprise an aqueous solution of a water soluble cerium salt or a dispersion of cerium oxide in water. The decontamination composition may optionally include at least one of an oxidizer, a surfactant, a co-solvent, a chelating agent, and a polymer. Methods of decontaminating clothing involve applying the decontamination composition to the clothing.

Decontamination compositions useful to decontaminate potentially toxic materials, such as PAH and others, present on clothing comprise an aqueous solution of a water soluble cerium salt or a dispersion of cerium oxide in water. The decontamination composition may optionally include at least one of an oxidizer, a surfactant, a co-solvent, a chelating agent, and a polymer. Methods of decontaminating clothing involve applying the decontamination composition to the clothing.

The present teachings are directed to inorganic oxide materials that include Al.sub.2O.sub.3, CeO.sub.2, and at least one of MgO and Pr.sub.6O.sub.11. The present teachings are also directed to catalysts having at least one noble metal supported on these inorganic oxide materials, as well as methods for treating exhaust gases from internal combustion engines using such catalysts.

The present teachings are directed to inorganic oxide materials that include Al.sub.2O.sub.3, CeO.sub.2, and at least one of MgO and Pr.sub.6O.sub.11. The present teachings are also directed to catalysts having at least one noble metal supported on these inorganic oxide materials, as well as methods for treating exhaust gases from internal combustion engines using such catalysts.

A slurry containing abrasive grains and a liquid medium, in which the abrasive grains include first particles and second particles in contact with the first particles, a particle size of the second particles is smaller than a particle size of the first particles, the first particles contain cerium oxide, the second particles contain a cerium compound, and in a case where a content of the abrasive grains is 0.1% by mass, an absorbance for light having a wavelength of 380 nm in a liquid phase obtained when the slurry is subjected to centrifugal separation for 5 minutes at a centrifugal acceleration of 5.8×10.sup.4 G exceeds 0.

A slurry containing abrasive grains and a liquid medium, in which the abrasive grains include first particles and second particles in contact with the first particles, a particle size of the second particles is smaller than a particle size of the first particles, the first particles contain cerium oxide, the second particles contain a cerium compound, and in a case where a content of the abrasive grains is 0.1% by mass, an absorbance for light having a wavelength of 380 nm in a liquid phase obtained when the slurry is subjected to centrifugal separation for 5 minutes at a centrifugal acceleration of 5.8×10.sup.4 G exceeds 0.

In an ultraviolet-shielding particle coated with silicon oxide of the present invention, a surface of the ultraviolet-shielding particle is coated with a silicon oxide coat, at least one functional group selected from the group consisting of an alkyl group, an alkenyl group, and a cycloalkyl group is present on a surface of the silicon oxide coat, and a content of the functional group is 0.0001% by mass or more and 0.30% by mass or less.

A slurry containing abrasive grains and a liquid medium, in which the abrasive grains contain at least one metal compound selected from the group consisting of a metal oxide and a metal hydroxide, the metal compound contains a metal capable of taking a plurality of valences, and when the slurry is brought into contact with a surface to be polished to bring the abrasive grains into contact with the surface to be polished, the slurry yields 0.13 or more in X-ray photoelectron spectroscopy as a ratio of the lowest valence among the plurality of valences of the metal.