A ceramic composition contains Fe, Cu, Ni, Zn, Co, and Cr. When Fe, Cu, Ni, and Zn are converted to Fe.sub.2O.sub.3, CuO, NiO, and ZnO, respectively, and a total amount of Fe.sub.2O.sub.3, CuO, NiO, and ZnO is 100 parts by mole, the ceramic composition contains from 48.20 to 49.85 parts by mole Fe in terms of Fe.sub.2O.sub.3, from 2.00 parts to 8.00 parts by mole Cu in terms of CuO, from 11.90 to 18.70 parts by mole Ni in terms of NiO, and from 27.00 to 33.50 parts by mole Zn in terms of ZnO. When Fe, Cu, Ni, and Zn are converted to Fe.sub.2O.sub.3, CuO, NiO, and ZnO, respectively, and a total amount of Fe.sub.2O.sub.3, CuO, NiO, and ZnO is 100 parts by weight, the ceramic composition contains from 5 to 100 ppm Co in terms of CoO and from 10 to 400 ppm in terms of Cr.sub.2O.sub.3.

A ferrite ceramic composition includes, as main components, from 27.0 mol % to 41.0 mol % of Fe in terms of Fe.sub.2O.sub.3, from 16.0 mol % to 24.0 mol % of Ni in terms of NiO, from 23.0 mol % to 37.0 mol % of Zn in terms of ZnO, from 5.0 mol % to 9.0 mol % of Cu in terms of CuO, and from 4.0 mol % to 14.0 mol % of Si in terms of SiO.sub.2, and as sub-components, relative to 100 parts by mass of the main components, from 0.3 parts by mass to 1.2 parts by mass of Bi in terms of Bi.sub.2O.sub.3, from 0.3 parts by mass to 1.2 parts by mass of Co in terms of Co.sub.3O.sub.4, from 0.01 parts by mass to 0.25 parts by mass of Mn in terms of Mn.sub.2O.sub.3, and from 0.003 parts by mass to 0.030 parts by mass of Cr in terms of Cr.sub.2O.sub.3.

A multilayer component and a mathod for producing a multilayer component are disclosed. In an embodiment the multilayer component includes a ceramic main element being a varistor ceramic and at least one metal structure, wherein the metal structure is cosintered, and wherein the main element is doped with a material of the metal structure in such a way that a diffusion of the material from the metal structure into the main element during a sintering operation is reduced.

A precursor of an alumina sintered compact including aluminum, yttrium, and at least one metal selected from iron, zinc, cobalt, manganese, copper, niobium, antimony, tungsten, silver, and gallium. The aluminum content is 98.0% by mass or more as an oxide (Al.sub.2O.sub.3) in 100% by mass of the precursor of an alumina sintered compact; the yttrium content is 0.01 to 1.35 parts by mass as an oxide (Y.sub.2O.sub.3) based on 100 parts by mass of the content of the aluminum as an oxide; the total content of the metals selected from the foregoing group is 0.02 to 1.55 parts by mass as an oxide based on 100 parts by mass of the content of aluminum as an oxide; and the aluminum is contained as α-alumina. Also disclosed is an alumina sintered compact, and a method for producing an alumina sintered compact and for producing abrasive grains.

The invention relates to a material for storing and releasing oxygen, consisting of a reactive ceramic made of copper, manganese and iron oxides, wherein, subject to the oxygen partial pressure of a surrounding atmosphere and/or an ambient temperature, the reactive ceramic has a transition region that can be passed through any number of times, said transition region being between a discharge threshold state of a three-phase crednerite/cuprite/hausmannite mixed ceramic and a charge threshold state of a two-phase spinel/tenorite mixed ceramic. A passing through of the transition region from the discharge threshold state towards the charging threshold state is associated with oxygen uptake and a passing through of the transition region from the charge threshold state towards the discharge threshold state is associated with oxygen release.

Electronic devices are produced from dielectric compositions comprising a mixture of precursor materials that, upon firing, forms a dielectric material comprising a barium-strontium-titanium-tungsten-silicon oxide.

A multilayer coil component including a magnetic part formed of a ferrite material, a non-magnetic part formed of a non-magnetic ferrite material, and a coiled conductive part embedded in the magnetic part and the non-magnetic part. The non-magnetic part has an Fe content of 36.0 to 48.5 mol % in terms of Fe.sub.2O.sub.3, a Zn content of 46.0 to 57.5 mol % in terms of ZnO, a V content of 0.5 to 5.0 mol % in terms of V.sub.2O.sub.5, a Mn content of 0 to 7.5 mol % in terms of Mn.sub.2O.sub.3, and a Cu content of 0 to 5.0 mol % in terms of CuO with respect to the sum of the Fe content in terms of Fe.sub.2O.sub.3, the Zn content in terms of ZnO, the V content in terms of V.sub.2O.sub.5, and if present, the Cu content in terms of CuO, and the Mn content in terms of Mn.sub.2O.sub.3.

A negative thermal expansion material and a preparation method thereof, and a negative thermal expansion film and a preparation method thereof are provided. The negative thermal expansion material includes Eu.sub.0.85Cu.sub.0.15MnO.sub.3-δ, wherein 0≤δ≤2.

(i) a step of disposing a powder that includes an absorber absorbing light of a wavelength included in a laser beam to be irradiated and silicon dioxide as a main component; (ii) a step of sintering or melting and solidifying the powder by irradiating the powder with a laser beam; and (iii) a step of heat-treating a shaped object formed by repeating the steps (i) and (ii) at 1470° C. or more and less than 1730° C.

Ceramic particles for use in a solar power tower and methods for making and using the ceramic particles are disclosed. The ceramic particle can include a sintered ceramic material formed from a mixture of a raw material and MnO. The sintered ceramic material can include about 0.01 wt % to about 10 wt % MnO, about 0.1 wt % to about 20 wt % Fe.sub.2O.sub.3, and about 0.01 wt % to about 10 wt % Mn.sub.2O.sub.3. The ceramic particle can have a size from about 8 mesh to about 170 mesh.