A multilayer ceramic capacitor includes a multilayer body including dielectric layers, inner-electrode layers, and outer electrodes coupled to the inner-electrode layers. The multilayer body includes Ba, Ti, Ca, Mg, Zr, and R, and when the Ti content is defined as 100 parts by mole, the relative amounts are as follows: Ca, 0.03 parts by mole or more and 0.15 parts by mole or less, Mg, 0.01 parts by mole or more and 0.09 parts by mole or less, R, 2.5 parts by mole or more and 8.4 parts by mole or less; Zr, 0.05 parts by mole or more and 3.00 parts by mole or less: Si, 0.5 parts by mole or more and 4.0 parts by mole or less; and P, 0.005 parts by mole or more and 0.500 parts by mole or less. Ca is in a vicinity of the center of crystal grains contained in the dielectric layers.

A ceramic electronic component includes a body, including a dielectric layer and an internal electrode. The dielectric layer includes a plurality of dielectric grains, and at least one of the plurality of dielectric grains has a core-dual shell structure having a core and a dual shell. The dual shell includes a first shell, surrounding at least a portion of the core, and a second shell, surrounding at least a portion of the first shell. The dual shell includes different types of rare earth elements R1 and R2, and R2.sub.S1/R1.sub.S1 is 0.01 or less and R2.sub.S2/R1.sub.S1 is 0.5 to 3.0, where R1.sub.S1 and R1.sub.S2 denote concentrations of R1 included in the first shell and the second shell, respectively, and R2.sub.S1 and R2.sub.S2 denote concentrations of R2 included in the first shell and the second shell, respectively.

The present disclosure includes proppants and methods of making the proppants. The proppants herein may contain titanium dioxide, silicon dioxide, and/or aluminum dioxide. Also included in the present disclosure are methods of using the proppants to treat a reservoir.

In an embodiment a ceramic material includes ZnO as main constituent, Y as a first additive, second additives including at least one compound containing a metal element, wherein the metal element is selected from the group consisting of Bi, Cr, Co, Mn, Ni and Sb, Si.sup.4+ as a first dopant and second dopants having at least one compound containing a metal cation from Al.sup.3+, B.sup.3+, or Ba.sup.2+, wherein a corresponds to a molar proportion of Bi calculated as Bi.sub.2O.sub.3, b corresponds to a molar proportion of Y calculated as Y.sub.2O.sub.3, c corresponds to a molar proportion of Al calculated as Al.sub.2O.sub.3, d corresponds to a molar proportion of Ba calculated as BaO, e corresponds to a molar proportion of B calculated as B.sub.2O.sub.3, f corresponds to a molar proportion of Si calculated as SiO.sub.2, g corresponds to a molar proportion of Ni calculated as NiO, h corresponds to a molar proportion of Co calculated as Co.sub.3O.sub.4, i corresponds to a molar proportion of Cr calculated as Cr.sub.2O.sub.3, j corresponds to a molar proportion of Sb calculated as Sb.sub.2O.sub.3, and k corresponds to a molar proportion of Mn calculated as Mn.sub.3O.sub.4.

A cubic boron nitride sintered material includes: more than or equal to 50 volume % and less than 80 volume % of cubic boron nitride grains; and more than 20 volume % and less than or equal to 50 volume % of a binder phase, and when an oxygen content is measured in a direction perpendicular to an interface between cubic boron nitride grains using TEM-EDX, a first region having an oxygen content larger than an average value of an oxygen content of a cubic boron nitride grain exists, the interface exists in the first region, and a length of the first region along the direction perpendicular to the interface is more than or equal to 0.1 nm and less than or equal to 10 nm.

The invention relates to a ceramic material, comprising lead zirconate titanate, which additionally contains K and optionally Cu. The ceramic material can be used in an electroceramic component, for example a piezoelectric actuator. The invention also relates to methods for producing the ceramic material and the electronic component.

A porous fired granulated body is formed by consolidating numerous alumina particles to each other while letting mainly interconnected pores remain in network form across an entire cross section of a granulated body particle (11). The pores (13) have an inner diameter controlled by a droplet diameter of a pore forming agent and have numerous precipitated alumina crystals (15) formed on inner surfaces thereof. Manufacture is performed by spraying the pore forming agent (emulsion) onto a raw material to form a coating layer of the pore forming agent on a surface of the raw material particle and controlling the inner diameter of the pores. A porous fired granulated body of alumina having a high specific surface area and having higher strength for the same specific surface area can thus be provided by a simple manufacturing method.

A multilayer electronic component that includes a stacked body having therein a plurality of dielectric layers including a CZ-based perovskite phase and an element M1, a plurality of internal electrode layers including Cu, and an interface layer including the element M1 in at least a portion of an interface with the plurality of internal electrode layers. Element M1 is an element that has a binding energy between CZ and Cu via the element M1 of less than or equal to −9.8 eV by first-principles calculation using a pseudopotential method. When amounts of elements included in the dielectric layers are expressed as parts by mol, a ratio m1 of an amount of the element M1 to an amount of the Zr in the interface layer is 0.03≤m1≤0.25.

A wavelength converter 100 includes: a first phosphor 1 composed of an inorganic phosphor activated by Ce.sup.3+; and a second phosphor 2 composed of an inorganic phosphor activated by Ce.sup.3+ and different from the first phosphor. At least one of the first phosphor and the second phosphor is particulate. The first phosphor and the second phosphor are bonded to each other by at least one of a chemical reaction in a contact portion between the compound that constitutes the first phosphor and a compound that constitutes the second phosphor and of adhesion between the compound that constitutes the first phosphor and the compound that constitutes the second phosphor.

Provided is a dielectric ceramic composition comprising a main component of forsterite and calcium strontium titanate. A content ratio of forsterite in the main component is from 84.0 to 92.5 parts by mole, and a content ratio of calcium strontium titanate is from 7.5 to 16.0 parts by mole. (Sr+Ca)/Ti in the calcium strontium titanate is from 1.03 to 1.20 in terms of a molar ratio. With respect to a total of 100 parts by mass of the main component and a subcomponent except for Li-containing glass, from 2 to 10 parts by mass of Li-containing glass is added. The Li-containing glass includes Al.sub.2O.sub.3 in an amount of from 1% by mass to 10% by mass.