Provided is a new cerium-based particle and a polishing slurry composition including the same. The new cerium-based particle may include a self-assembly of fine particles and an organic material.

A complex oxide powder contains cerium, zirconium, and aluminum and, has a specific surface area of 0.5 m.sup.2/g or more and 10 m.sup.2/g or less.

A complex oxide powder contains cerium, zirconium, and aluminum and, has a specific surface area of 0.5 m.sup.2/g or more and 10 m.sup.2/g or less.

The polishing particles of the present disclosure has controlled particle size and particle size distribution of cerium oxide particles comprised in the polishing particles, and thereby can suppress the formation of a scratch which may occur in a polishing process while having a characteristic of a high polishing rate.

The polishing particles of the present disclosure has controlled particle size and particle size distribution of cerium oxide particles comprised in the polishing particles, and thereby can suppress the formation of a scratch which may occur in a polishing process while having a characteristic of a high polishing rate.

Cerium oxide nanoparticles (CNPs) have been proven to exhibit antioxidant properties attributed to its surface oxidation states (Ce4+ to Ce3+ and vice versa) mediated at the oxygen vacancies on the surface of CNPs. Different anions in precursor cerium salts were used to prepare CNPs resulting in disclosed CNPs with varying physicochemical properties such as dispersion stability, hydrodynamic size, and the signature surface chemistry. The antioxidant catalytic activity and oxidation potentials of different CNPs have been significantly altered with the change of anions in the precursor salts. For one, CNPs prepared using precursor salts containing NO.sub.3.sup.− and Cl.sup.− ions exhibited increased antioxidant activity than previously thought possible. The change in oxidation potentials of CNPs with the change in concentration of the nitrate and chloride ions indicates the disclosed CNP's have different surface chemistry and antioxidant properties. These compositions and methods of their synthesis are disclosed.

Cerium oxide nanoparticles (CNPs) have been proven to exhibit antioxidant properties attributed to its surface oxidation states (Ce4+ to Ce3+ and vice versa) mediated at the oxygen vacancies on the surface of CNPs. Different anions in precursor cerium salts were used to prepare CNPs resulting in disclosed CNPs with varying physicochemical properties such as dispersion stability, hydrodynamic size, and the signature surface chemistry. The antioxidant catalytic activity and oxidation potentials of different CNPs have been significantly altered with the change of anions in the precursor salts. For one, CNPs prepared using precursor salts containing NO.sub.3.sup.− and Cl.sup.− ions exhibited increased antioxidant activity than previously thought possible. The change in oxidation potentials of CNPs with the change in concentration of the nitrate and chloride ions indicates the disclosed CNP's have different surface chemistry and antioxidant properties. These compositions and methods of their synthesis are disclosed.

A metal double salt dispersion liquid including an organic solvent and a metal double salt, wherein the metal double salt has a composition represented by M(R.sup.1COO).sub.m-x-y(OH).sub.xA.sub.y(H.sub.2O).sub.z, where M is a metal element, R.sup.1 is a hydrogen atom or an alkyl group, A is an anion, m is a valence of the metal element M, 0<x+y<m, x>0, y≥0, and z≥0, and when the metal double salt dispersion liquid is subjected to a centrifugal operation at a relative centrifugal force of 10,000 G for 5 minutes, a proportion of metal elements not forming a precipitate to all metal elements contained in a total of the metal double salt dispersion liquid is 10.0 mol % or more.

The present disclosure discloses a method for preparing rare earth oxide by recycling ammonia and carbon, comprising the steps of: (1) heating raw materials containing a first rare earth carbonate and a first rare earth oxide with microwave and calcining at 500-1000° C. for 20-120 min to obtain a second rare earth oxide and carbon dioxide; (2) reacting carbon dioxide with a first ammonia water to obtain a precipitant; (3) reacting the precipitant with rare earth chloride to obtain a second rare earth carbonate and ammonium chloride wastewater. In the method, calcination time is short, rare earth recovery rate, utilization rate of ammonia and carbon resources are high. The present disclosure also provides a use of a rare earth oxide in shortening calcination time and/or increasing rare earth yield.

The object of the present invention is to provide silicon doped metal oxide particles for UV absorption, which average molar absorption coefficient in the wavelength range of 200 nm to 380 nm, is enhanced. Provided is silicon doped metal oxide particles in which the metal oxide particles are doped with silicon, wherein an average molar absorption coefficient in the wavelength range of 200 nm to 380 nm, of a dispersion in which the silicon doped metal oxide particles are dispersed in a dispersion medium, is improved as compared with similar metal oxide particles not doped with silicon.