Disclosed is provision of a ceramic coat having an excellent low-particle generation as well as a method for assessing the low-particle generation of the ceramic coat. A composite structure including a substrate and a structure which is formed on the substrate and has a surface, wherein the structure includes a polycrystalline ceramic and the composite structure has luminance Sa satisfying a specific value calculated from a TEM image analysis thereof, can be suitably used as an inner member of a semiconductor manufacturing apparatus required to have a low-particle generation.

A hydrothermal method of preparing uniform, monodisperse ceramic lanthanum hydroxyl carbonate (LaCO.sub.3OH) having cherry-blossom-like nanogears and/or nanocubes is described. The method produced a hexagonal crystal with a crystal lattice in which at least on lanthanum ion is substituted with calcium ion. The ceramic nanoparticles produced by the method are good catalyst for the reduction of nitrogen oxides with a hydrocarbon. A method of reducing exhaust gases is described.

A hydrothermal method of preparing uniform, monodisperse ceramic lanthanum hydroxyl carbonate (LaCO.sub.3OH) having cherry-blossom-like nanogears and/or nanocubes is described. The method produced a hexagonal crystal with a crystal lattice in which at least on lanthanum ion is substituted with calcium ion. The ceramic nanoparticles produced by the method are good catalyst for the reduction of nitrogen oxides with a hydrocarbon. A method of reducing exhaust gases is described.

An object of the present invention is to provide a method for producing oxide particles with controlled color characteristics and to provide oxide particles with controlled color characteristics. The present invention provides a method for producing oxide particles, comprising controlling color characteristics of the oxide particles by controlling the ratio of M-OH bonds, the binding of one or more different elements (M) other than oxygen or hydrogen with hydroxyl group (OH), in oxide particles selected from metal oxide particles and metalloid oxide particles. According to the present invention, oxide particles having controlled color characteristics of any one of reflectance, transmittance, molar absorption coefficient, hue, or color saturation can be provided by controlling the percentage of the M-OH bonds contained in metal oxide particles or metalloid oxide particles.

Methods are provided for forming high temperature coating over ceramic components, such as ceramic turbomachine components. In various embodiments, the method includes the step or process of at least partially filling a reactor vessel with a reaction solution containing a solution-borne rare earth cation source. A silicon-containing surface region of a ceramic component is submerged in the reaction solution, and a solvothermal growth process is carried-out. During the solvothermal growth process, the reaction solution is subject to elevated temperature and pressure conditions within the reactor vessel in the presence of a silicate anion source, which reacts with the solution-borne rare earth cation source to grow a rare earth silicate layer over the silicon-containing surface region of the ceramic component.

A composition including cerium and zirconium oxides, including at least 30 wt.-% cerium oxide is desired. Following calcination at a temperature of 900 DEG C. for 4 hours, the composition has two populations of pores, the diameters of the first population being centered around a value of between 5 nm and 15 nm for a composition including 30% to 65% cerium oxide or between 10 nm and 20 nm for more than 65% cerium oxide and the diameter of the second population being centered around a value of between 45 nm and 65 nm for 30% to 65% cerium oxide or between 60 nm and 100 nm for more than 65% cerium oxide.

An embodiment provides a phosphor composition and a light emitting device package comprising the same, wherein the phosphor composition comprises green phosphor, amber phosphor, and red phosphor, wherein the amber phosphor is expressed as chemical formula Li.sub.m2XSi.sub.12mnAl.sub.m+nO.sub.nN.sub.16n:Eu.sup.2+, where 2m5, 2n10, 0.01X1. The light emitting element package of the embodiment can display white light having improved brightness and color rendering index.

The invention relates to rare-earth-doped ternary sulfides. The rare-earth-doped ternary sulfides may be used as an active material for mid-wave infrared and long-wave infrared lasers and amplifiers. Methods for producing laser materials including rare-earth-doped ternary sulfides, as well as lasers and amplifiers incorporating the laser materials, are also provided.

Monodisperse particles having: a single pure crystalline phase of a rare earth-containing lattice, a uniform three-dimensional size, and a uniform polyhedral morphology are disclosed. Due to their uniform size and shape, the monodisperse particles self assemble into superlattices. The particles may be luminescent particles such as down-converting phosphor particles and up-converting phosphors. The monodisperse particles of the invention have a rare earth-containing lattice which in one embodiment may be an yttrium-containing lattice or in another may be a lanthanide-containing lattice. The monodisperse particles may have different optical properties based on their composition, their size, and/or their morphology (or shape). Also disclosed is a combination of at least two types of monodisperse particles, where each type is a plurality of monodisperse particles having a single pure crystalline phase of a rare earth-containing lattice, a uniform three-dimensional size, and a uniform polyhedral morphology; and where the types of monodisperse particles differ from one another by composition, by size, or by morphology. In a preferred embodiment, the types of monodisperse particles have the same composition but different morphologies. Methods of making and methods of using the monodisperse particles are disclosed.

A ceria composite particle dispersion has ceria composite particles having an average particle size of 50 to 350 nm and having the features described below. Each ceria composite particle has a mother particle, a cerium-containing silica layer on the surface thereof, and child particles dispersed inside the cerium-containing silica layer, the mother particles being amorphous silica-based and the child particles being crystalline ceria-based. The child particles have a coefficient of variation (CV value) in a particle size distribution of 14 to 40%. The ceria composite particles have a mass ratio of silica to ceria of 100:11-316. Only the crystal phase of ceria is detected when the ceria composite particles are subjected to X-ray diffraction. The average crystallite size of the crystalline ceria measured by subjecting the ceria composite particles to X-ray diffraction is 10 to 25 nm.