Provided is a honeycomb catalyst in which a plurality of through holes are provided in proximity to each other in a row arrangement in the lengthwise direction, and are set apart by partitions. A honeycomb unit contains at least two types of inorganic particles and an inorganic binder. The inorganic particles contain zeolite having an SiO2/Al2O3 composition ratio of less than 15 and a CHA structure and an oxide other than zeolite, which has a positive thermal expansion coefficient. The ratio (X:Y) of the volume (X) of zeolite and the volume (Y) of oxide is 50:50 to 80:20. A displacement amount of absorbed water is reduced and cracking is controlled while maintaining high NOx purging performance.

Disclosed herein are compounds, methods, and tools which comprise tungsten borides and mixed transition metal borides.

A method for producing a multilayer ceramic capacitor that includes preparing a dielectric ceramic material by mixing a perovskite compound, a Re compound, a Mn compound, a Mg compound, and a Si compound. The perovskite compound contains Ba and Ti and has 1.2×10.sup.15 or more and 4.5×10.sup.15 or less Ba vacancies per gram. Re in the Re compound is at least one element selected from Y, Gd, Tb, Dy, Ho, Er, and Yb. Green sheets containing the dielectric ceramic material are then formed. Inner electrode patterns are then formed on some of the green sheets. An unsintered capacitor body is then formed by stacking the green sheets, some of which have the inner electrode patterns formed thereon. Sintering of the unsintered capacitor body is then conducted.

The object of the present invention is to provide the dielectric ceramic composition having good characteristics even under the high electric field intensity, and particularly good IR characteristic and the high temperature accelerated lifetime. The dielectric ceramic composition according to the present invention comprises a main component comprising a perovskite type compound shown by a compositional formula (Ba.sub.1-x-ySr.sub.xCa.sub.y).sub.m(Ti.sub.1-zZr.sub.z)O.sub.3 (note that, said “m”, “x”, “y” and “z” all show a mol ratio, and each satisfies 0.94≦m≦1.1, 0≦x≦0.2, 0≦y≦0.2, 0.06≦z<0.2), a first sub component comprising oxides of a rare earth element R (note that, R is any one selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu), a second sub component comprising oxides of Mg, a third sub component comprising oxides at least one element M selected from the group consisting of Mn, Cr, Co and Fe, a fourth sub component as a sintering agent, a ratio of the first sub component in terms of oxides (RO.sub.3/2) is 8 to 20 mol, a ratio of the second sub component in terms of oxides (MgO) is 3 to 15 mol, a ratio of the third sub component in terms of oxides (MO) is 0.6 to 2.0 mol, with respect to 100 mol of said main component; and when a content of the first sub component is R mol, a content of the second sub component is M mol, and a content of the third sub component is N mol with respect to 100 mol of said main component, then 1.0≦R(M+N)≦2.4 is satisfied.

A dielectric ceramic composition has good characteristics even under the high electric field intensity, and particularly good IR characteristic and the high temperature accelerated lifetime. The dielectric ceramic composition has a main component having a perovskite type compound shown by a compositional formula (Ba.sub.1-x-ySr.sub.xCa.sub.y).sub.m(Ti.sub.1-zZr.sub.z)O.sub.3, a first sub component having oxides of a rare earth element R, a second sub component as a sintering agent, wherein the dielectric particles has dielectric particles having high diffusion rate of the rare earth element, preferably of a complete solid solution particle, and when a concentration of Ti atom in the diffusion phase is 100 atom %, then an average concentration of the rare earth element R in the diffusion phase is 5 atom % or more, and an average concentration of Zr in the diffusion phase is 10 atom % or more.

A dielectric ceramic composition having good characteristic even under high electric field intensity, and particularly good IR characteristic and high temperature accelerated lifetime. The present invention is a dielectric ceramic composition comprising, a main component comprising a perovskite type compound shown by a compositional formula (Ba1-x-ySrxCay)m(Ti1-zZrz)O3, a first sub component comprising oxides of a rare earth element, a second sub component as a sintering agent, wherein said dielectric ceramic composition is a complete solid solution particle wherein the rare earth element is solid dissolved to entire dielectric particle, or a core-shell particle having high ratio of the diffusion phase, and comprises the dielectric particle having 5 to 20 atom % of the average concentration of the rare earth element in the diffusion phase, and having uniform concentration distribution of the rare earth element in the diffusion phase.

The invention provides a shuttle kiln that can fire ceramic porous bodies containing organic binders in a shorter period of time than in conventional methods without occurring breaks due to a temperature difference between the inside and the outside. The shuttle kiln of the invention is suited for firing of ceramic porous bodies containing organic binders. It includes a gas suction path 4 that suctions in-furnace gas and discharges it via an afterburner 5 and a circulation path 7 that suctions the in-furnace gas to the furnace outside to burn organic binder gas and then returns it into the furnace.

Provided are: a MnZn-based ferrite which allows to have a low magnetic core loss and to suppress a time-dependent change of magnetic property under a high-temperature environment by a control of ambient oxygen concentration and an increase of the magnetic core loss, and a method for manufacturing the same. The MnZn-based ferrite is characterized in that Fe ranges from 53.25 mol % or more to 54.00 mol % or less on the basis of Fe.sub.2O.sub.3, Zn ranges from 2.50 mol % or more to 8.50 mol % or less on the basis of ZnO and Mn is the remainder on the basis of MnO, Si ranges from more than 0.001 mass % to less than 0.02 mass % on the basis of SiO.sub.2, Ca ranges from more than 0.04 mass % to less than 0.4 mass % on the basis of CaCO.sub.3, Co is less than 0.5 mass % on the basis of Co.sub.3O.sub.4, Bi is less than 0.05 mass % on the basis of Bi.sub.2O.sub.3, Ta is less than 0.05 mass % on the basis of Ta.sub.2O.sub.5, Nb is less than 0.05 mass % on the basis of Nb.sub.2O.sub.5, Ti is less than 0.3 mass % on the basis of TiO.sub.2, and Sn is less than 0.3 mass % on the basis of SnO.sub.2, and note that the converted total amount of Ta.sub.2O.sub.5 and Nb.sub.2O.sub.5 is less than 0.05 mass % and the converted total amount of TiO.sub.2 and SnO.sub.2 is less than 0.3 mass %.

An NTC component comprising a first electrode (1) and a second electrode (2) is specified. The NTC component further comprises an NTC element (3) disposed between the first electrode (1) and the second electrode (2), wherein the NTC element (3) comprises a ceramic having the general composition AB.sub.2O.sub.4, and where A and B each comprise one or more of the materials Mn, Ni, Co and Cu, and B additionally comprises one or more of the materials Fe, Y, Pr, Al, In, Ga and Sb.

Electronic devices are produced from dielectric compositions comprising a mixture of precursor materials that, upon firing, forms a dielectric material comprising a barium-strontium-titanium-tungsten-silicon oxide.