Disclosed herein are embodiments of an enhanced resonant frequency hexagonal ferrite material and methods of manufacturing. The hexagonal ferrite material can be Y-phase strontium hexagonal ferrite material. In some embodiments, sodium can be added into the crystal structure of the hexagonal ferrite material in order to achieve high resonance frequencies while maintaining high permeability.

Disclosed herein are embodiments of an enhanced resonant frequency hexagonal ferrite material, such as Y-phase hexagonal ferrite material, and methods of manufacturing. In some embodiments, sodium or potassium can be added into the crystal structure of the hexagonal ferrite material in order to achieve improved resonant frequencies in the range of 500 MHz to 1 GHz useful for radiofrequency applications.

Disclosed herein are embodiments of modified z-type hexagonal ferrite materials having improved properties that are advantageous for radiofrequency applications, in particular high frequency ranges for antennas and other devices. Atomic substitution of strontium, aluminum, potassium, and trivalent ions can be used to replace certain atoms in the ferrite crystal structure to improve loss factor at high frequencies.

Disclosed herein are embodiments of an enhanced resonant frequency hexagonal ferrite material and methods of manufacturing. The hexagonal ferrite material can be Y-phase strontium hexagonal ferrite material. In some embodiments, strontium can be substituted out for a trivalent or tetravalent ion composition including potassium, thereby providing for advantageous properties.

A fuel cell comprises a plurality of sub-cells, each sub-cell including a first electrode in fluid communication with a source of oxygen gas, a second electrode in fluid communication with a source of a fuel gas, and a solid electrolyte between the first electrode and the second electrode. The sub-cells are connected with each other with an interconnect. The interconnect includes a first layer in contact with the first electrode of each cell, and a second layer in contact with the second electrode of each cell. The first layer includes a (La,Mn)Sr-titanate based perovskite represented by the empirical formula of La.sub.ySr.sub.(1-y)Ti.sub.(1-x)Mn.sub.xO.sub.b. In one embodiment, the second layer includes a (Nb,Y)Sr-titanate perovskite represented by the empirical formula of Sr.sub.(1-1.5z-0.5k)Y.sub.zNb.sub.kTi.sub.(1-k)O.sub.d. In another embodiment, the interconnect has a thickness of between about 10 m and about 100 m, and the second layer of the interconnect includes a (La)Sr-titanate based perovskite represented by the empirical formula of Sr.sub.(1-z)La.sub.zTiO.sub.d.

A fuel cell has an anode, a cathode, and a solid electrolyte layer. The cathode contains a main component configured by a perovskite oxide which is expressed by the general formula ABO.sub.3 and includes at least one of La and Sr at the A site. The solid electrolyte layer is disposed between the anode and the cathode. The cathode includes an interface region that is within 5 m from a surface near to the solid electrolyte layer. The interface region contains a main phase configured by the perovskite oxide, and a secondary phase configured by strontium oxide. An occupied surface area ratio of the secondary phase in a cross section of the interface region is greater than or equal 0.05% and less than or equal to 3%.

A magnetoelectric effect material includes as a primary component, a polycrystalline oxide ceramic containing at least Sr, Co, and Fe. In the polycrystalline oxide ceramic, the crystal c-axis is oriented in a predetermined direction, and the degree of orientation of the c-axis is 0.2 or more by a Lotgering method. A component substrate is formed of this magnetoelectric effect material.

An oxide ceramic represented by the general formula [Sr.sub.2xBa.sub.xCo.sub.2y(Zn.sub.uNi.sub.1u).sub.yFe.sub.12zAl.sub.zO.sub.22]. In the formula, 0.7x1.3 and 0.8z1.2. y is 0y0.8 when 0.5u1.0 and is 0y1.6 when 0u0.5. y is preferably 0.4 or less. Further, a variable inductor as a ceramic electronic component has a component base body formed from the oxide ceramic.

A multilayer ceramic substrate that includes a laminate having stacked ceramic layers formed of a ceramic material containing a main component, containing 48 to 75% by weight of Si, 20 to 40% by weight of Ba, and 10 to 40% by weight of Al, and an auxiliary component containing at least 2.5 to 20 parts by weight of Mn with respect to 100 parts by weight of the main component, and in the laminate, glass ceramic layers in which the entire or a portion of the thickness thereof exists within 100 m inside of the laminate as measured from opposed principal surfaces are further stacked.

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.