There is provided a ferrite sintered magnet having a high residual magnetic flux density.

A ferrite sintered magnet 2 includes a plurality of main phase particles 5 including ferrite having a hexagonal structure, the number of core-shell structured particles 5A having a core 7 and a shell 9 covering the core 7, among the main phase particles 5, is smaller than the number of the main phase particles 5 other than the core-shell structured particles 5A.

Disclosed herein are embodiments of an enhanced resonant frequency hexagonal ferrite material and methods of manufacturing. The hexagonal ferrite material can be Y-phase hexagonal ferrite material, such as those including strontium. In some embodiments, oxides consistent with the stoichiometry of Sr.sub.3Co.sub.2Fe.sub.24O.sub.41, SrFe.sub.12O.sub.19 or CoFe.sub.2O.sub.4 can be used form an enhanced hexagonal ferrite material.

Provided is a ferrite sintered magnet including a main phase formed of ferrite having a hexagonal magnetoplumbite type crystalline structure, in which the main phase contains Fe and Co, and the ferrite sintered magnet contains CaB.sub.2O.sub.4. CaB.sub.2O.sub.4 is contained in a heterophase that is a crystalline phase different from the main phase, and an area ratio of CaB.sub.2O.sub.4 to the entire cross-sectional surface of a sintered magnet, is less than or equal to 2%.

A ferrite composition having a formula of Ba.sub.xNi.sub.2-yCu.sub.yTi.sub.3Fe.sub.zO.sub.31, wherein 4.5?x?5.5 0<y<2 or 0.05?y?1.5, and 11?z?13.

Disclosed herein are embodiments of composite hexagonal ferrite materials formed from a combination of Y phase and Z phase hexagonal ferrite materials. Advantageously, embodiments of the material can have a high resonant frequency as well as a high permeability. In some embodiments, the materials can be useful for magnetodielectric antennas.

The present invention provides a ferrite magnetic material that is inexpensive by reducing the contents of La and Co and capable of providing a remarkably high maximum energy product ((BH).sub.max) as compared with the conventional ferrite magnetic materials by inducing a high saturation magnetization and a high anisotropic magnetic field.

A ferrite sintered magnet includes a composition expressed by a formula (1) of Ca.sub.1-w-xLa.sub.wA.sub.xFe.sub.zCo.sub.mO.sub.19. In the formula (1), w, x, z, and m satisfy a formula (2) of 0.30w0.50, a formula (3) of 0.08x0.20, a formula (4) of 8.55z10.00, and a formula (5) of 0.20m0.40. In the formula (1), A is at least one kind of element selected from a group consisting of Sr and Ba. Cr is further contained at 0.058 mass % to 0.132 mass % in terms of Cr.sub.2O.sub.3.

This ferrite magnet has a ferrite phase having a magnetoplumbite structure, and an orthoferrite phase, and is characterized in that the composition ratios of the total of each metal element A, R, Fe and Me is represented by expression (1) A.sub.1-xR.sub.x(Fe.sub.12-yMe.sub.y).sub.z, (in expression (1), A is at least one element selected from Sr, Ba, Ca and Pb; R is at least one element selected from the rare-earth elements (including Y) and Bi, and includes at least La, and Me is Co, or Co and Zn) and in that the content (m) of the orthoferrite phase is 0<m<28.0 in mol %. The invention makes it possible to achieve a ferrite magnet with increased Br.

A fuel cell comprises an anode, a cathode, a solid electrolyte layer, and a current collecting member. The cathode contains a perovskite composite oxide as a main component and contains a compound that includes at least one of S and Cr as a secondary component. The cathode has a surface facing the current collecting member. The surface of the cathode includes a first region that is electrically connected to the current collecting member and a second region that is separated from the current collecting member. The first region and the second region respectively contain a main phase that is configured from a perovskite composite oxide and a secondary phase that is configured from the compound. The occupied surface area ratio of the secondary phase in the first region is greater than the occupied surface area ratio of the secondary phase in the second region.

Disclosed herein are doped perovskite oxides. The doped perovskite oxides may be used as a cathode material in an electrochemical cell to electrochemically generate ammonia from N.sub.2. The doped perovskite oxides may be combined with nitride compounds, for instance iron nitride, to further increase the efficiency of the ammonia production.