The present invention relates to a powder for sintering containing a mixture of a metal powder and metal oxide particles having an average particle diameter of 5 nm or more and 200 nm or less, and to a sintered body.

A method for producing a Group III nitride crystal, includes: preparing an RAMO.sub.4 substrate containing a single crystal represented by the general formula RAMO.sub.4 (wherein R represents one or a plurality of trivalent elements selected from a group consisting of Sc, In, Y, and a lanthanoid element, A represents one or a plurality of trivalent elements selected from a group consisting of Fe(III), Ga, and Al, and M represents one or a plurality of divalent elements selected from a group consisting of Mg, Mn, Fe(II), Co, Cu, Zn, and Cd) and having a notch on a side portion thereof; growing a Group III nitride crystal on the RAMO.sub.4 substrate; and cleaving the RAMO.sub.4 substrate from the notch.

Provided is a method for recovering scandium, with which it is possible to easily and efficiently recover high-purity scandium from nickel oxide ores. This method for recovering scandium involves passing a solution containing scandium through an ion exchange resin, then subjecting the eluant eluted from the ion exchange resin to solvent extraction and separating the extraction residual liquid and the extraction agent after extraction, then performing an oxalation process on the extraction residual liquid to obtain a scandium oxalate precipitate, and roasting the precipitate to obtain scandium oxide, wherein the method is characterized in that an amine-based extraction agent is used as the extraction agent for solvent extraction.

The present invention relates to a catalyst for transfer hydrogenation, which is formed of a metal-organic framework having an MOF-808 based X-ray diffraction pattern.

A high crystalline porous MOF-808 based metal-organic framework exhibits excellent performance in the transfer hydrogenation of ethyl levulinate (EL) at high and low temperature.

A method of preparing a fine powder of calcium lanthanoid sulfide is disclosed. The method includes spraying soluble calcium and lanthanoid salts into at least one precipitating solution to form a precipitate comprising insoluble calcium and lanthanoid salts, optionally, oxidizing the precipitate comprising insoluble calcium and lanthanoid salts, and sulfurizing the optionally oxidized precipitate to form a fine powder of calcium lanthanoid sulfide. An alternative method for forming the powder is by flame pyrolysis. The calcium lanthanoid sulfide powder produced by either method can have an impurity concentration of less than 100 ppm, a carbon concentration of less than 200 ppm, a BET surface area of at least 50 m.sup.2/g, and an average particle size of less than 100 nm.

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.

The present invention disclosed use of lactam as a solvent in the preparation of nanomaterials by precipitation method, sol-gel method or high temperature pyrolysis. These methods are able to recycle lactam solvent, which meet requirements of environmental protection.

Disclosed are a composite oxide which is capable of maintaining a large volume of pores even used in a high temperature environment, and which has excellent heat resistance and catalytic activity, as well as a method for producing the composite oxide and a catalyst for exhaust gas purification employing the composite oxide. The composite oxide contains cerium and at least one element selected from aluminum, silicon, or rare earth metals other than cerium and including yttrium, at a mass ratio of 85:15 to 99:1 in terms oxides, and has a property of exhibiting a not less than 0.30 cm.sup.3/g, preferably not less than 0.40 cm.sup.3/g volume of pores with a diameter of not larger than 200 nm, after calcination at 900° C. for 5 hours, and is suitable for a co-catalyst in a catalyst for vehicle exhaust gas purification.

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.

[Objective] To provide a ceramic emitter that exhibits high radiation intensity and excellent wavelength selectivity.

[Solution] A ceramic emitter includes a polycrystalline body that has a garnet structure represented by a compositional formula R.sub.3Al.sub.5O.sub.12 (R: rare-earth element) or R.sub.3Ga.sub.5O.sub.12 (R: rare-earth element) and has pores with a porosity of 20-40%. The pores have a portion where the pores are connected to one another but not linearly continuous, inside the polycrystalline body.