A Faraday rotator and an optical isolator having a high transmittance and a high Verdet constant are provided. The optical isolator includes at least a Faraday rotator that rotates a polarization plane of incident light in a non-reciprocal manner, a polarizer disposed on a light incident side of the Faraday rotator, and an analyzer disposed on a light exit side of the Faraday rotator. The Faraday rotator is made of an oxide containing ytterbium oxide (Yb.sub.2O.sub.3), and is manufactured by a ceramic manufacturing process, wherein the oxide is allowed to contain an oxide of a metal other than ytterbium, and the proportion of ytterbium in all metal atoms in the oxide is 80% or more.

There is provided at least any of a layered body which has a change in color tone and in which it is unnecessary to select a colorant and the content of the colorant in consideration of a difference in the sintering behavior between layers, a precursor thereof, or a method for producing these. Provided is a layered body which has a structure, in which two or more layers containing stabilizer-containing zirconia and a colorant are layered, and in which types and contents of the colorants contained in the layers are equal to each other, the layered body including at least: a first layer containing a colorant and zirconia which has a stabilizer content of higher than or equal to 3.3 mol %; and a second layer containing a colorant and zirconia which has a stabilizer content different from that of the zirconia contained in the first layer.

A dielectric body includes a plurality of crystal grains of which a main component is barium titanate, and an additive including Zr, Eu and Mn. At least one of the plurality of crystal grains has a core-shell structure having a core and a shell. A Zr/Ti atomic concentration ratio is 0.02 or more and 0.10 or less. An Eu/Ti atomic concentration ratio is 0.001 or more and 0.03 or less. A Mn/Ti atomic concentration ratio is 0.005 or more and 0.05 or less. A total atomic concentration of the one or more rare elements is smaller than an atomic concentration of Eu when the dielectric body has the one or more rare earth elements. A median diameter of the plurality of crystal grains is 200 nm or more and 400 nm or less.

Provided is a dielectric ceramic composition including a first component and a second component, wherein the first component comprises an oxide of Ca of 0.00 mol % to 35.85 mol % an oxide of Sr of 0.00 mol % to 47.12 mol %, an oxide of Ba of 0.00 mol % to 51.22 mol %, an oxide of Ti of 0.00 mol % to 17.36 mol %, an oxide of Zr of 0.00 mol % to 17.36 mol %, an oxide of Sn of 0.00 mol % to 2.60 mol %, an oxide of Nb of 0.00 mol % to 35.32 mol %, an oxide of Ta of 0.00 mol % to 35.32 mol %, and an oxide of V of 0.00 mol % to 2.65 mol %, and the second component includes at least (a) an oxide of Mn of 0.005% by mass to 3.500% by mass and (b) an oxide of Cu and/or an oxide of Ru.

A zirconia powder containing a stabilizer, and having a specific surface area of 20 m.sup.2/g or more and 60 m.sup.2/g or less and a particle diameter D.sub.50 of 0.1 μm or more and 0.7 μm or less, in which in a range of 10 nm or more and 200 nm or less in a pore distribution based on a mercury intrusion method, a peak top diameter in a pore volume distribution is 20 nm or more and 85 nm or less, a pore volume is 0.2 ml/g or more and less than 0.5 ml/g, and a pore distribution width is 40 nm or more and 105 nm or less.

The present invention provides a method of producing a honeycomb structured body having excellent mechanical strength. The present invention relates to a method of producing a honeycomb structured body including a honeycomb fired body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween, the method including: a raw material mixing step of preparing a raw material paste containing ceria-zirconia composite oxide particles, alumina particles, an inorganic binder, and alumina fibers; a molding step of molding the raw material paste into a honeycomb molded body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; a drying step of drying the honeycomb molded body obtained in the molding step; and a firing step of firing the honeycomb molded body dried in the drying step into a honeycomb fired body, wherein the percentage of amorphous alumina fibers in the alumina fibers for use in the raw material mixing step is 50 to 100 wt %.

The present invention provides a method of producing a honeycomb structured body having excellent mechanical strength. The present invention relates to a method of producing a honeycomb structured body including a honeycomb fired body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween, the method including: a raw material mixing step of preparing a raw material paste containing ceria-zirconia composite oxide particles, alumina particles, an inorganic binder, and inorganic fibers; a molding step of molding the raw material paste into a honeycomb molded body in which multiple through-holes are arranged longitudinally in parallel with one another with a partition wall therebetween; a drying step of drying the honeycomb molded body obtained in the molding step; and a firing step of firing the honeycomb molded body dried in the drying step into a honeycomb fired body, wherein the raw material mixing step includes pre-mixing of the inorganic binder and the inorganic fibers.

An improved ceramic material for heat insulation with selection of specific stabilizers and adapted proportions, includes zirconium oxide with 0.2 wt. % to 8.0 wt. % of the base stabilizers: yttrium oxide (Y.sub.2O.sub.3), hafnium oxide (HfO.sub.2), cerium oxide (CeO.sub.2), calcium oxide (CaO), and/or magnesium oxide (MgO), wherein at least yttrium oxide (Y.sub.2O.sub.3) is used, and optionally at least one of the additional stabilizers: 0.2 wt. % to 20 wt. % of erbium oxide (Er.sub.2O.sub.3) and/or ytterbium oxide (Yb.sub.2O.sub.3).

A center flare tip assembly (16) and plenum flare tip assembly (18) with arms (20), having the outside of the center flare tip assembly (16), both inside and outside of the tips (18), the outside of the arms (20), and/or adjacent features of the flare tip (12) are covered with a high emissivity thermal layer (14) with an emissivity greater than 0.85. This reduces flare metal temperatures by thirty percent (30%) or greater, and increases flare life by two (2) to five (5) times current life.

A multilayer electronic component includes a body including a dielectric layer and an internal electrode; and an external electrode disposed on the body and connected to the internal electrode, wherein the dielectric layer includes first and second grains, wherein the first grain has a core-shell structure including a shell having an atomic ratio of 2*Sn/(Ba+Ti+Sn) or 2*Hf/(Ba+Ti+Hf) to be 1.0% or more and 5.0% or less, and a core having an atomic ratio of 2*Sn/(Ba+Ti+Sn) and 2*Hf/(Ba+Ti+Hf) to be less than 1.0%, and the second grain has an atomic ratio of 2*Sn/(Ba+Ti+Sn) and 2*Hf/(Ba+Ti+Hf) to be less than 1.0%, and wherein an area occupied by the first grain in an entire area of the first and second grains is 28.3-82.3%.