A ferrite sintered body contains Fe, Mn, Zn, Cu, and Ni. Supposing that Fe, Mn, Zn, Cu, and Ni are converted into Fe.sub.2O.sub.3, Mn.sub.2O.sub.3, ZnO, CuO, and NiO, respectively, and the sum of the contents of Fe.sub.2O.sub.3, Mn.sub.2O.sub.3, ZnO, CuO, and NiO is 100 mol %, the sum of the contents of Fe.sub.2O.sub.3 and Mn.sub.2O.sub.3 is 48.47 mol % to 49.93 mol %, the content of Mn.sub.2O.sub.3 is 0.07 mol % to 0.37 mol %, the content of ZnO is 28.95 mol % to 33.50 mol %, and the content of CuO is 2.98 mol % to 6.05 mol %. Furthermore, 102 ppm to 4,010 ppm Zr in terms of ZrO.sub.2 and 10 ppm to 220 ppm Al in terms of Al.sub.2O.sub.3 are contained per 100 parts by weight of the sum of the amounts of contained Fe.sub.2O.sub.3, Mn.sub.2O.sub.3, ZnO, CuO, and NiO.

A multilayer ceramic capacitor includes: a multilayer structure in which each of dielectric layers and each of internal electrode layers are stacked, wherein a relationship of 8.0≥I.sub.A/I.sub.B>1.40 is satisfied in a TSDC (Thermally Stimulated Depolarization Currents) of temperature elevation rate of 10 degrees C./min under a condition of 130 degrees C., 5 V/μm and a polarization of 30 min, when a peak current value on a lower temperature side in a temperature range of 130 degrees C. to 190 degrees C. is I.sub.A and a peak current value on a higher temperature side in a temperature range of 190 degrees C. to 280 degrees C. is I.sub.B.

It is an object of the present disclosure to provide a thin-film carbon foam and a method of manufacture the same. It is another object of the present disclosure to provide a stack carbon foam having fewer through holes and a method of manufacturing the same. The carbon foam of the present disclosure is, for example, a stack carbon foam being a stack of at least two monolayer carbon foams stacked one another, each monolayer carbon foam comprising linear portions and node portions joining the linear portions, or a carbon foam comprising linear portions and node portions joining the linear portions, wherein the ratio of the number of large through holes having a diameter of 1 mm or more to the surface area of the carbon foam is 0.0003/mm.sup.2 or less.

A sintered body, containing zinc, magnesium and oxygen as constituent elements, wherein the atomic ratio of zinc to the sum of zinc and magnesium [Zn/(Zn+Mg)] is 0.20 to 0.75, the atomic ratio of magnesium to the sum of zinc and magnesium [Mg/(Zn+Mg)] is 0.25 to 0.80, and the sintered body consists of a single crystal structure as measured by X-ray diffraction.

Set forth herein are processes and materials for making ceramic thin films by casting ceramic source powders and precursor reactants, binders, and functional additives into unsintered thin films and subsequently sintering the thin films under controlled atmospheres and on specific substrates.

The present invention addresses the problem of providing: a porous carbon structure that has a high micropore volume and can be self-contained; a manufacturing method therefor; a positive electrode material using the same; and a battery (particularly an air battery) using the same. The present invention is a porous carbon structure that is for a positive electrode for an air battery and has voids and a skeleton formed by incorporating carbon, the porous carbon structure satisfying all of the following conditions (a) to (d). (a) The t-plot external specific surface area is within the range of 300m.sup.2/g to 1600m.sup.2/g; (b) the total volume of micropores having a diameter of lnm to 200 nm is within the range of 1.2 cm.sup.3/g to 7.0cm.sup.3/g; (c) the total volume of micropores having a diameter of lnm to 1000 nm is within the range of 2.3cm3/g to 10.0 cm.sup.3/g; and (d) the overall porosity is within the range of 80% to 99%.

A sintered ferrite magnet having a composition of metal elements of Ca, R, A, Fe and Co, which is represented by the general formula of Ca.sub.1−x−yR.sub.xA.sub.yFe.sub.2n−zCo.sub.z, wherein R is at least one of rare earth elements indispensably including La; A is Sr and/or Ba; x, y, z and n represent the atomic ratios of Ca, R, A, Fe and Co; 2n represents a molar ratio expressed by 2n=(Fe+Co)/(Ca+R+A); and x, y, z and n meet the conditions of 0.15≤x≤0.35, 0.05≤y≤0.40, (1−x−y)>y, 0<z≤0.18, and 7.5≤(2n−z)<11.0.

A ceramic electronic device includes: a multilayer structure in which each of dielectric layers and each of internal electrode layers are alternately stacked, a main component of the dielectric layers being ceramic, wherein a relationship of I.sub.A/I.sub.B>1.40 is satisfied in a TSDC (Thermally Stimulated Depolarization Currents) of temperature elevation rate of 10 degrees C./min under a condition of 130 degrees C., 5 V/μm and a polarization of 30 min, when a peak current value on a lower temperature side in a temperature range of 130 degrees C. to 190 degrees C. is I.sub.A and a peak current value on a higher temperature side in a temperature range of 190 degrees C. to 280 degrees C. is I.sub.B.

A dielectric material includes a perovskite as a main phase, an A site of the perovskite including at least Ba, a B site of the perovskite including at least Ti, and Eu having +2 valence and +3 valence. A ratio of +2 valence of Eu is 21% or more.

A sintered ferrite magnet having a composition of metal elements of Ca, R, A, Fe and Co, which is represented by the general formula of Ca.sub.1-x-yR.sub.xA.sub.yFe.sub.2n-zCo.sub.z, wherein R is at least one of rare earth elements indispensably including La; A is Sr and/or Ba; x, y, z and n represent the atomic ratios of Ca, R, A, Fe and Co; 2n represents a molar ratio expressed by 2n=(Fe+Co)/(Ca+R+A); and x, y, z and n meet the conditions of 0.15≤x≤0.35, 0.05≤y≤0.40, (1-x-y)>y, 0<z≤0.18, and 7.5≤(2n-z)<11.0.