A slurry of a dispersion medium and rare earth oxide particles. The particles having a volume basis median particle size D50 of up to 50 nm. The rare earth oxide particles having a dispersity index S of up to 1, the dispersity index S being determined according to the formula (1):
(D90D10)/D50(1) wherein D10, D50 and D90 are cumulative 10%, 50% and 90% diameters in volume basis particle size distribution, respectively.

Novel hybrid nanoparticles, useful for inhibiting or slowing down the formation of sulfur deposits or minerals in a well during the extraction of gas or oil. Specifically, the nanoparticles each include (i) a polyorganosiloxane (POS) matrix; and, optionally as a coating over a lanthanide oxide core, (iii) at least one polymeric scale inhibitor during the extraction of gas or oil. The invention also relates to the method for obtaining the nano-inhibitors and the application of same.

A method of producing ceria nanocrystals is provided. The method includes providing a gas that includes ozone to a solution that includes a cerium salt, and obtaining ceria nanocrystals from the solution after the gas is provided to the first solution. A method of producing nanoparticles is provided. The method includes providing a gas that includes ozone to a solution that includes a metal salt that includes at least one of a transition metal or a lanthanide, and producing at least one of metal oxide nanoparticles, metal oxynitrate nanoparticles, or metal oxyhydroxide nanoparticles from the solution after the gas is provided to the solution.

An anticorrosive pigment comprising an aluminum polyphosphate comprises at least one cerium-based compound and/or one lanthanum-based compound and/or one praseodymium-based compound. An anticorrosive paint incorporating the pigment is also provided.

Ceramic powder to be used for additive manufacturing of a ceramic object by irradiating the powder with laser light includes a first group of particles of a first inorganic compound showing an average particle diameter of not less than 10 m and not more than 100 m and a second group of particles of a second inorganic compound having an absorption band at the wavelength of the laser light and showing an average particle diameter smaller than the average particle diameter of the first group of particles. Particles belonging to the second group of particles are arranged on the surfaces of particles belonging to the first group of particles. A high-precision ceramic object can be obtained in a short time by using the ceramic powder.

A process for separating rare earth elements (REE) from Ca, Mg and other non-REE elements comprises raising the pH of an acidic aqueous solution of REE to pH 8 to pH 11; adding nano- or micro (NoM) particles having a silica or titanium oxide surface; agitating the suspension for 6 h to 48 h to provide for adherent crystallization of REE hydroxide on the particles; separating the particles from the solution; releasing REE by treatment with aqueous acid to form an aqueous solution of REE salt; separating them from the aqueous solution of REE salt formed. The acidic aqueous solution comprising REE is preferably provided by leaching of an REE mineral with aqueous acid; adding a base to bring the pH to from pH 4.0 to pH 6.5; separating precipitated non-REE hydroxide from the solution.

A starting material powder, which contains a rare earth oxide that is composed of terbium oxide and at least one other rare earth oxide selected from among yttrium oxide, scandium oxide and oxides of lanthanide rare earth elements (excluding terbium) and a sintering assistant that is formed of an oxide of at least one element selected from among group 2 elements and group 4 elements, is produced by having (a) terbium ions, (b) ions of at least one other rare earth element selected from among yttrium ions, scandium ions and lanthanide rare earth ions (excluding terbium ions) and (c) ions of at least one element selected from among group 2 elements and group 4 elements coprecipitate in an aqueous solution containing the components (a)-(c), then filtering and separating the coprecipitate, and subjecting the separated coprecipitate to thermal dehydration.

Disclosed here is a method for making a monolithic rare earth oxide (REO) aerogel, comprising: preparing a reaction mixture comprising at least one rare earth metal nitrate, at least one epoxide, at least one base catalyst, and at least one organic solvent; curing the mixture to produce a wet gel; drying the wet gel to produce a dry gel; and thermally annealing the dry gel to produce the monolithic REO aerogel. Also disclosed is an REO aerogel comprising a network of REO nanostructures, wherein the REO aerogel is a monolith having at least one lateral dimension of at least 1 cm, wherein the REO aerogel has a density of about 40-500 mg/cm.sup.3 and/or a BET surface area of at least about 20 m.sup.2/g, and wherein the REO aerogel is substantially free of oxychloride.

Disclosed here is a method for making a monolithic rare earth oxide (REO) aerogel, comprising: preparing a reaction mixture comprising at least one rare earth metal nitrate, at least one epoxide, at least one base catalyst, and at least one organic solvent; curing the mixture to produce a wet gel; drying the wet gel to produce a dry gel; and thermally annealing the dry gel to produce the monolithic REO aerogel. Also disclosed is an REO aerogel comprising a network of REO nanostructures, wherein the REO aerogel is a monolith having at least one lateral dimension of at least 1 cm, wherein the REO aerogel has a density of about 40-500 mg/cm.sup.3 and/or a BET surface area of at least about 20 m.sup.2/g, and wherein the REO aerogel is substantially free of oxychloride.

Nanoplatelet forms of metal hydroxide and metal oxide are provided, as well as methods for preparing same. The nanoplatelets are suitable for use as fire retardants and as agents for chemical or biological decontamination.