Provided are metal oxide ceramic materials and intermediate materials thereof (e.g., nanozirconia gels, nanozirconia green bodies, pre-sintered ceramic bodies, zirconia dental ceramic materials, and dental articles). The nanozirconia gels are formable gels. Also provided are methods of making and using the metal oxide materials and intermediate materials. The nanozirconia gels can be made using, for example, osmotic processing. The nanozirconia gels can be used to make nanozirconia green bodies, pre-sintered ceramic bodies, zirconia dental ceramic materials, and dental article. The nanozirconia green bodies, pre-sintered ceramic bodies, zirconia dental ceramic materials, and dental articles have desirable properties (e.g., optical properties and mechanical properties).

A method for producing a photo-luminescent material, including the following steps: (1) producing, according to a sol-gel method, a sol and then a gel of first precursors of a first substance from the sol; (2) crushing the gel; (3) optionally, annealing the gel in order to form first particles of the first substance of which the average size is between 1 pm and 20 um; (4) producing a colloidal dispersion of second particles of a second substance, different from the first substance or identical to the first substance, of which the average size is between 5 nm and 400 nm; (5) mixing the colloidal dispersion with the sol in step (1) before forming the gel or with the first particles after step (3); and (6) annealing the mixture obtained in step (5), resulting in an increase in the compactness of the mixture, the average size of the second particles after annealing being between 100 nm and 900 nm. A photo-luminescent material including a mixture of first particles of a first photo-luminescent substance of which the average size is between 1 pm and 20 pm and second particles of a second photo-luminescent substance, different from the first photo-luminescent substance or identical to the first photo-luminescent substance, of which the average size is between 100 nm and 900 nm.

A method for producing a photo-luminescent material, including the following steps: (1) producing, according to a sol-gel method, a sol and then a gel of first precursors of a first substance from the sol; (2) crushing the gel; (3) optionally, annealing the gel in order to form first particles of the first substance of which the average size is between 1 pm and 20 um; (4) producing a colloidal dispersion of second particles of a second substance, different from the first substance or identical to the first substance, of which the average size is between 5 nm and 400 nm; (5) mixing the colloidal dispersion with the sol in step (1) before forming the gel or with the first particles after step (3); and (6) annealing the mixture obtained in step (5), resulting in an increase in the compactness of the mixture, the average size of the second particles after annealing being between 100 nm and 900 nm. A photo-luminescent material including a mixture of first particles of a first photo-luminescent substance of which the average size is between 1 pm and 20 pm and second particles of a second photo-luminescent substance, different from the first photo-luminescent substance or identical to the first photo-luminescent substance, of which the average size is between 100 nm and 900 nm.

Radiofrequency and other electronic devices can be formed from textured hexaferrite materials, such as Z-phase barium cobalt ferrite Ba.sub.3Co.sub.2Fe.sub.24O.sub.41 (Co.sub.2Z) having enhanced resonant frequency. The textured hexaferrite material can be formed by sintering fine grain hexaferrite powder at a lower temperature than conventional firing temperatures to inhibit reduction of iron. The textured hexaferrite material can be used in radiofrequency devices such as circulators or telecommunications systems.

Radiofrequency and other electronic devices can be formed from textured hexaferrite materials, such as Z-phase barium cobalt ferrite Ba.sub.3Co.sub.2Fe.sub.24O.sub.41 (Co.sub.2Z) having enhanced resonant frequency. The textured hexaferrite material can be formed by sintering fine grain hexaferrite powder at a lower temperature than conventional firing temperatures to inhibit reduction of iron. The textured hexaferrite material can be used in radiofrequency devices such as circulators or telecommunications systems.

Methods, structures, devices and systems are disclosed for fabricating and implementing nanoparticles with hollow core and sealable holes. In one aspect, a nanoparticle device can includes a shell structure including at least two layers including an internal layer and an external layer, the internal layer structured to enclose a hollow interior region and include one or more holes penetrating the internal layer, the external layer is of a porous material and formed around the internal layer and sealing the one or more holes, and a substance contained within the hollow interior region, the substance incapable of passing through the external layer.

Methods, structures, devices and systems are disclosed for fabricating and implementing nanoparticles with hollow core and sealable holes. In one aspect, a nanoparticle device can includes a shell structure including at least two layers including an internal layer and an external layer, the internal layer structured to enclose a hollow interior region and include one or more holes penetrating the internal layer, the external layer is of a porous material and formed around the internal layer and sealing the one or more holes, and a substance contained within the hollow interior region, the substance incapable of passing through the external layer.

Disclosed are an inorganic nanofiber characterized in that the average fiber diameter is 2 μm or less, the average fiber length is 200 μm or less, and the CV value of the fiber length is 0.7 or less; and a method of manufacturing the same. In the manufacturing method, an inorganic nanofiber sheet consisting of inorganic nanofibers having an average fiber diameter of 2 μm or less is formed by electrospinning, and then, the inorganic nanofiber sheet is pressed using a press machine and crushed so that the average fiber length becomes 200 μm or less, and the CV value of the fiber length becomes 0.7 or less.

There is described a mesoporous composite material comprising carbon nanoparticles dispersed in a mesoporous carbonaceous material.

There is described a mesoporous composite material comprising carbon nanoparticles dispersed in a mesoporous carbonaceous material.