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 ferrite magnet includes: a hexagonal ferrite main phase; and a second phase. The second phase is an oxide phase containing: an element A which is at least one selected from the group consisting of Ca, Sr, Ba, Bi, and rare earth elements; a transition metal element T including at least Fe; and an element G which is at least one selected from the group consisting of Si, Al, B, F, K, Na, Li, P, and S. When the total number of atoms of the element A, the transition metal element T, and the element G in the second phase is set to 100 at %, the element A occupies 30 to 80 at %, the element G occupies 15 to 40 at %, and the transition metal element T occupies less than 4 at %.

Herein discussed is a method of sintering a ceramic comprising (a) providing an electromagnetic radiation (EMR) source; (b) (i) providing a layer of intermixed ceramic particles and absorber particles, wherein the absorber particles have a volume fraction in the intermixed particles in the range of no less than 3%; or (ii) providing a first layer comprising ceramic particles and a second layer comprising absorber particles in contact with at least a portion of the first layer, wherein the second layer is farther from the EMR source than the first layer; (c) heating (i) the layer of intermixed particles or (ii) the first layer using EMR; and (d) controlling the EMR such that at least a portion of the ceramic particles are sintered wherein (i) the layer of intermixed particles becomes impermeable or (ii) the first layer becomes impermeable, wherein the absorber particles have greater EMR absorption than the ceramic particles.

Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of bismuth can be added into specific sites in the crystal structure of the synthetic garnet in order to boost certain properties, such as the dielectric constant and magnetization. Accordingly, embodiments of the disclosed materials can be used in high frequency applications, such as in base station antennas.

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 ferrite sintered magnet including 0.010 mass % or more and 0.090 mass % or less of Mg in terms of MgO.

Disclosed are embodiments of synthetic garnet materials for use in radiofrequency applications. In some embodiments, increased amounts of bismuth can be added into specific sites in the crystal structure of the synthetic garnet in order to boost certain properties, such as the dielectric constant and magnetization. Accordingly, embodiments of the disclosed materials can be used in high frequency applications, such as in base station antennas.

The present invention provides a ferrite sintered magnet comprising ferrite crystal grains having a hexagonal structure, wherein the ferrite sintered magnet comprises metallic elements at an atomic ratio represented by formula (1). In formula (1), R is at least one element selected from the group consisting of Bi and rare-earth elements, and R comprises at least La. In formula (1), w, x, z and m satisfy formulae (2) to (5). The above-mentioned ferrite sintered magnet further has a coefficient of variation of a size of the crystal grains in a section parallel to a c axis of less than 45%.

Ca.sub.1-w-xR.sub.wSr.sub.xFe.sub.zCo.sub.m(1)

0.360w=0.420(2)

0.110x0.173(3)

8.51z9.71(4)

0.208m0.269(5)

A method is described of producing a catalyst-containing composite oxygen ion membrane and a catalyst-containing composite oxygen ion membrane in which a porous fuel oxidation layer and a dense separation layer and optionally, a porous surface exchange layer are formed on a porous support from mixtures of (Ln.sub.1xA.sub.x).sub.wCr.sub.1yB.sub.yO.sub.3 and a doped zirconia. Adding certain catalyst metals into the fuel oxidation layer not only enhances the initial oxygen flux, but also reduces the degradation rate of the oxygen flux over long-term operation. One of the possible reasons for the improved flux and stability is that the addition of the catalyst metal reduces the chemical reaction between the (Ln.sub.1xA.sub.x).sub.wCr.sub.1yB.sub.yO.sub.3 and the zirconia phases during membrane fabrication and operation, as indicated by the X-ray diffraction results.

Herein discussed is a method of sintering a ceramic comprising (a) providing an electromagnetic radiation (EMR) source; (b) (i) providing a layer of intermixed ceramic particles and absorber particles, wherein the absorber particles have a volume fraction in the intermixed particles in the range of no less than 3%; or (ii) providing a first layer comprising ceramic particles and a second layer comprising absorber particles in contact with at least a portion of the first layer, wherein the second layer is farther from the EMR source than the first layer; (c) heating (i) the layer of intermixed particles or (ii) the first layer using EMR; and (d) controlling the EMR such that at least a portion of the ceramic particles are sintered wherein (i) the layer of intermixed particles becomes impermeable or (ii) the first layer becomes impermeable, wherein the absorber particles have greater EMR absorption than the ceramic particles.