A variable-temperature and fast-sintering process for an alumina-doped zinc oxide target material is provided. Integrated degreasing and sintering processes are carried out on an alumina-doped zinc oxide biscuit, The degreasing process is carried out in air atmosphere, and a high-density alumina-doped zinc oxide target material is produced by a variable-temperature treatment during the sintering process under a state of circulating controllable mixed atmosphere. The mixed atmosphere is air and oxygen. As a result, a sintering time is greatly reduced, so that a fast-activated sintering is realized to inhibit grain growth.

A dielectric composition includes a main-phase particle and segregation particles. The main-phase particle includes a main component having a perovskite crystal structure represented by a general formula of ABO.sub.3. The dielectric composition includes RA, RB, M, and Si. Each of A, B, RA, RB, and M is one or more elements selected from a specific element group. Each of an RA content C.sub.RA to the main component, an RB content C.sub.RB to the main component, an M content to the main component, and a Si content to the main component is within a predetermined range. 0.50<(α/β)/(C.sub.RA/C.sub.RB)≤1.00 is satisfied, where a is an average RA content (mol %) and f3 is an average RB content (mol %) of specific segregation particles mainly including RA, RB, Si, Ba, and Ti in the segregation particles.

A dielectric composition includes main-phase particles each including a main component having a perovskite crystal structure represented by a general formula of ABO.sub.3. At least a part of the main-phase particles has a core-shell structure. The dielectric composition includes RA, RB, M, and Si. Each of A, B, RA, RB, and M is one or more elements selected from a specific element group. S.sub.RA/S.sub.RB>C.sub.RA/C.sub.RB is satisfied, where C.sub.RA is an RA content (mol %) to the main component in terms of RA.sub.2O.sub.3, and C.sub.RB is an RB content (mol %) to the main component in terms of RB.sub.2O.sub.3, in the dielectric composition, and S.sub.RA is an average RA content (mol %), and S.sub.RB is an average RB content (mol %), in a shell part of the core-shell structure.

A dielectric composition includes a main phase and segregation phases each including RE (at least one rare earth element). The main phase includes a main component having a perovskite crystal structure of ABO.sub.3 (A is one or more selected from Ba, Sr, and Ca, and B is one or more selected from Ti, Zr, and Hf). The segregation phases are classified into first segregation phases whose atomic ratio of Si to RE is 0 or more and 0.20 or less and second segregation phases whose atomic ratio of Si to the RE is more than 0.20. 0≤S1/S2≤0.10 is satisfied on a cross section of the dielectric composition, where S1 is an area ratio of the first segregation phases, and S2 is an area ratio of the second segregation phases. An atomic ratio of Si to RE in the second segregation phases is 0.80 or less on average.

A dielectric composition includes a main phase, first segregation phases, and second segregation phases. The main phase includes a main component having a perovskite crystal structure of ABO.sub.3 (A is one or more selected from Ba, Sr, and Ca, and B is one or more selected from Ti, Zr, and Hf). The first segregation phases include RE (one or more selected from rare earth elements), A, Si, Ti, and O. The second segregation phases include RE, A, Ti, and O and do not substantially include Si. 0.10<S2/S1≤1.50 is satisfied on a cross section of the dielectric composition, where S1 is an area ratio of the first segregation phases, and S2 is an area ratio of the second segregation phases.

Provided are a method for producing a ceramic sintered body having improved light emission intensity, a ceramic sintered body, and a light emitting device. The method for producing a ceramic sintered body comprises preparing a molded body that contains a nitride fluorescent material having a composition containing: at least one alkaline earth metal element M.sup.1 selected from the group consisting of Ba, Sr, Ca, and Mg; at least one metal element M.sup.2 selected from the group consisting of Eu, Ce, Tb, and Mn; Si; and N, wherein a total molar ratio of the alkaline earth metal element M.sup.1 and the metal element M.sup.2 in 1 mol of the composition is 2, a molar ratio of the metal element M.sup.2 is a product of 2 and a parameter y and wherein y is in a range of 0.001 or more and less than 0.5, a molar ratio of Si is 5, and a molar ratio of N is 8, and wherein the nitride fluorescent material has a crystallite size, as calculated by X-ray diffraction measurement using the Halder-Wagner method, of 550 Å or less, and calcining the molded body at a temperature in a range of 1,600° C. or more and 2,200° C. or less to obtain a sintered body.

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 DC conductive, low RF/microwave loss titanium oxide ceramic provides, at room temperature, a bulk DC resistivity of less than 1×10.sup.11 ohm-meters and an RF loss tangent of less than 2×10.sup.−4 at 7.5 GHz and less than 2×10.sup.−5 at 650 MHz. The resistivity is reduced by oxygen vacancies and associated Ti.sup.3+ and/or Ti.sup.4+ centers created by sintering in an atmosphere containing only between 0.01% and 0.1% oxygen. The reduced resistivity prevents DC charge buildup, while the low loss tangent provides good RF/microwave transparency and low losses. The ceramic is suitable for forming RF windows, electron gun cathode insulators, dielectrics, and other components. An exemplary Mg.sub.2TiO.sub.4—MgTiO.sub.3 embodiment includes mixing, grinding, pre-sintering in air, and pressing 99.95% pure MgO and TiO.sub.2 powders, re-sintering in air at 1400° C.-1500° C. to reduce porosity, and sintering at 1350° C.-1450° C. for 4 hours in an 0.05% oxygen and 99.05% nitrogen atmosphere.

A ceramic electronic device includes a multilayer structure having a parallelepiped shape in which a plurality of dielectric layers and a plurality of internal electrode layers are alternately stacked in a vertical direction, the plurality of internal electrode layers being alternately exposed to two end faces of the parallelepiped shape. A side margin section is a section covering edges of the plurality of internal electrode layers in an extension direction toward two side faces of the parallelepiped shape. The side margin section has a structure in which a plurality of dielectric layers, each containing a ceramic as a main component, and a plurality of conductive layers, each containing a metal as a main component, are alternately stacked in the vertical direction. The plurality of conductive layers are respectively spaced and separated from the plurality of internal electrode layers.

Described herein are Uranium silicide materials as advanced nuclear fuel replacements for uranium dioxide fuel in light water reactors (LWRs) that have advantages over currently used uranium dioxide (UO.sub.2) via a substantially higher thermal conductivity and, thus, are capable of operating in a reactor at significantly lower temperatures for the same level of power production, plus the heat capacity of a silicide is lower than that of an oxide so that less heat is stored in the fuel that would need to be removed under accident conditions.