A material including TiO.sub.2 nanoparticles at least partially embedded in a matrix material of Ti.sub.xNb.sub.yO.sub.z, where 0<x≤2, 0<y≤24, and 0<z≤62, is provided. Methods of making the material are also provided.

A nanometer niobium carbide/carbon nanotube reinforced diamond composite and a preparation method thereof, belonging to the field of materials science. The nanometer niobium carbide/carbon nanotube reinforced diamond composite is composed of nanometer niobium carbide/carbon nanotube composite powders, matrix powders and diamond grains, wherein the nanometer niobium carbide/carbon nanotube composite powders are the composites of nanometer niobium carbide which are evenly distributed in the surface defects and interior of the carbon nanotube, the nanometer niobium carbide/carbon nanotube reinforced diamond composite is prepared by mixing the nanometer niobium carbide/carbon nanotube composite powders, matrix powders and diamond grains uniformly and sintering with a hot pressing technique.

Provided is a piezoelectric material filler including alkali niobate compound particles having a ratio (K/(Na+K)) of the number of moles of potassium to the total number of moles of sodium and potassium of 0.460 to 0.495 in terms of atoms and a ratio ((Li+Na+K)/Nb) of the total number of moles of alkali metal elements to the number of moles of niobium of 0.995 to 1.005 in terms of atoms. The present invention can provide a piezoelectric material filler having excellent piezoelectric properties, and a composite piezoelectric material including the piezoelectric material filler and a polymer matrix.

A nonaqueous electrolyte battery according to one embodiment includes a negative electrode, a positive electrode and a nonaqueous electrolyte. The negative electrode includes a negative electrode active material-containing layer. The negative electrode active material-containing layer contains a negative electrode active material containing an orthorhombic Na-containing niobium titanium composite oxide. The positive electrode includes a positive electrode active material-containing layer. The positive electrode active material-containing layer contains a positive electrode active material. A mass C [g/m.sup.2] of the positive electrode active material per unit area of the positive electrode and a mass A [g/m.sup.2] of the negative electrode active material per unit area of the negative electrode satisfy the formula (1): 0.95≤A/C≤1.5.

A nonaqueous electrolyte battery according to one embodiment includes a negative electrode, a positive electrode and a nonaqueous electrolyte. The negative electrode includes a negative electrode active material-containing layer. The negative electrode active material-containing layer contains a negative electrode active material containing an orthorhombic Na-containing niobium titanium composite oxide. The positive electrode includes a positive electrode active material-containing layer. The positive electrode active material-containing layer contains a positive electrode active material. A mass C [g/m.sup.2] of the positive electrode active material per unit area of the positive electrode and a mass A [g/m.sup.2] of the negative electrode active material per unit area of the negative electrode satisfy the formula (1): 0.95≤A/C≤1.5.

Provided are an oxide semiconductor excellent in transparency, mobility, and weatherability, etc., and a semiconductor device having the oxide semiconductor, a p-type semiconductor being realizable in the oxide semiconductor. The oxide semiconductor consists of a composite oxide, which has a crystal structure including a pyrochlore structure, containing at least one or more kinds of elements selected from Nb and Ta, and containing Sn element, and its holes become charge carriers by the condition that Sn.sup.4+/(Sn.sup.2++Sn.sup.4+) which is a ratio of Sn.sup.4+ to a total amount of Sn in the composite oxide is 0.124≤Sn.sup.4+/(Sn.sup.2++Sn.sup.4+)≤0.148.

A piezoelectric composition including copper and a complex oxide having a perovskite structure represented by a general formula ABO.sub.3, in which an A site element in the ABO.sub.3 is potassium or potassium and sodium, a B site element in the ABO.sub.3 is niobium or niobium and tantalum, the copper is included in n mol % in terms of a copper element with respect to 1 mol of the complex oxide, and n satisfies 0.100≤n≤1.000.

According to one embodiment, there is provided an active substance. The active substance includes secondary particles and a carbon material phase formed on at least a part of a surface of each of the secondary particles. Each of the secondary particles is constructed by aggregated primary particles of an active material. The primary particles of the active material includes a niobium composite oxide represented by Li.sub.xM.sub.(1−y)Nb.sub.yNb.sub.2O.sub.(7+δ), wherein M is at least one selected from the group consisting of Ti and Zr, and x, y, and δ respectively satisfy 0≦x≦6, 0≦y≦1, and −1≦δ≦1. The secondary particles have a compression fracture strength of 10 MPa or more.

According to one embodiment, there is provided an active substance. The active substance includes secondary particles and a carbon material phase formed on at least a part of a surface of each of the secondary particles. Each of the secondary particles is constructed by aggregated primary particles of an active material. The primary particles of the active material includes a niobium composite oxide represented by Li.sub.xM.sub.(1−y)Nb.sub.yNb.sub.2O.sub.(7+δ), wherein M is at least one selected from the group consisting of Ti and Zr, and x, y, and δ respectively satisfy 0≦x≦6, 0≦y≦1, and −1≦δ≦1. The secondary particles have a compression fracture strength of 10 MPa or more.

Novel methods for processing fumed metallic oxides into globular metallic oxide agglomerates are provided. The methodology may allow for fumed metallic oxide particles, such as fumed silica and fumed alumina particles, to be processed into a globular morphology to improve handling while retaining a desirable surface area. The processes may include providing fumed metallic oxide particles, combining the particles with a liquid carrier to form a suspension, atomizing the solution of suspended particles, and subjecting the atomized droplets to a temperature range sufficient to remove the liquid carrier from the droplets, to produce metallic oxide-containing agglomerations.