A scintillation crystal can include Ln.sub.(1-y)RE.sub.yX.sub.3, wherein Ln represents a rare earth element, RE represents a different rare earth element, y has a value in a range of 0 to 1, and X represents a halogen. In an embodiment, RE is Ce, and the scintillation crystal is doped with Sr, Ba, or a mixture thereof at a concentration of at least approximately 0.0002 wt. %. In another embodiment, the scintillation crystal can have unexpectedly improved linearity and unexpectedly improved energy resolution properties. In a further embodiment, a radiation detection system can include the scintillation crystal, a photosensor, and an electronics device. Such a radiation detection system can be useful in a variety of radiation imaging applications.

Provided is a method for producing a β-sialon fluorescent material, comprising preparing a composition containing a silicon nitride that contains aluminium, oxygen, and europium; heat-treating the composition at a temperature in a range of 1300° C. or more and 1600° C. or less to obtain a heat-treated product; subjecting the heat-treated product to a temperature-decrease of from the heat treatment temperature to 1000° C. as a first temperature-decrease step; and subjecting the heat-treated product to a temperature-decrease of from 1000° C. to 400° C. as a second temperature-decrease step. The first temperature-decrease step has a temperature-decrease rate in a range of 1.5° C./min or more and 200° C./min or less, and the second temperature-decrease step has a temperature-decrease rate in a range of 1° C./min or more and 200° C./min or less.

One aspect of the disclosure provides an optical wavelength conversion member including a polycrystalline ceramic sintered body containing, as main components, Al.sub.2O.sub.3 crystal grains and crystal grains represented by formula (Y,A).sub.3B.sub.5O.sub.12:Ce. In the optical wavelength conversion member, a (Y,A).sub.3B.sub.5O.sub.12:Ce crystal grain has a region wherein the A concentration of a peripheral portion of the (Y,A).sub.3B.sub.5O.sub.12:Ce crystal grain is higher than that of an interior portion of the (Y,A).sub.3B.sub.5O.sub.12:Ce crystal grain. Thus, the optical wavelength conversion member exhibits high fluorescence intensity (i.e., high emission intensity) and high heat resistance (i.e., low likelihood of temperature quenching). The optical wavelength conversion member has a structure wherein the element A concentration of a peripheral portion of a (Y,A).sub.3B.sub.5O.sub.12:Ce crystal grain differs from that in an interior portion of the crystal grain. This structure can achieve a ceramic fluorescent body exhibiting superior fluorescent characteristics and superior thermal characteristics with varied colors of emitted light.

Provided is a ceramic composite material and a wavelength converter. The ceramic composite material includes: an alumina matrix, a fluorescent powder uniformly distributed in the alumina matrix, and scattering centers uniformly distributed in the alumina matrix, wherein the alumina matrix is an alumina ceramics, the scattering centers are alumina particles, the alumina particles each have a particle diameter of 1 μm to 10 μm, and the fluorescent powder has a particle diameter of 13 μm to 20 μm.

A process for preparing roofing granules includes forming kaolin clay into green granules and sintering the green granules at a temperature of at least 900 degrees Celsius to cure the green granules until the crystalline content of the sintered granules is at least ten percent as determined by x-ray diffraction.

A light-emitting ceramic that includes a pyrochlore type compound that contains 0.01 mol % or more of Bi with respect to 100 mol % of the general formula M1.sub.XM2.sub.YM3.sub.ZO.sub.W, wherein M1 is at least one of La, Y, Gd, Yb, and Lu, M2 is at least one of Zr, Sn, and Hf, M3 is at least one of Ta, Nb, and Sb, X, Y, Z, and W are positive numbers that maintain electrical neutrality, X+Y+Z=2.0, 0.005≤Z≤0.2, and 3X+4Y+5Z is 7.02 or less.

A composition comprises a zirconia powder, in which 55% or more thereof is monoclinic, and a stabilizer capable of suppressing phase transition of zirconia. An average particle diameter of zirconia particles and particles of the stabilizer is 0.06 μm to 0.17 μm. At least a portion of the stabilizer does not form a solid solution with zirconia.

A paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiO.sub.2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:
(Tb.sub.1-x-yY.sub.xSc.sub.y).sub.3(Al.sub.1-zSc.sub.z).sub.5O.sub.12  (1)
wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

The present disclosure provides a method of making a ceramic article. The method includes (a) obtaining a photopolymerizable slurry or sol including a plurality of ceramic particles distributed in the photopolymerizable slurry or sol and (b) selectively polymerizing the photopolymerizable slurry or sol using actinic radiation and continuous movement of a build substrate through the photopolymerizable slurry or sol to form a gelled article. The method also includes (c) extracting solvent from the gelled article to form an aerogel article or a xerogel article; (d) heat treating the aerogel article or the xerogel article to form a porous ceramic article; and (e) sintering the porous ceramic article to form a sintered ceramic article. The sintered ceramic article exhibits a particular density. Further, additive manufactured ceramic articles are provided that exhibit a particular density, opacity, or both. Preferably, all cross-sectional portions of an interior of the ceramic article having selected dimensions are free of a frequency analysis signal maxima larger than a background signal.

A phosphor plate includes a plate-like composite including a base material and an α-type sialon phosphor present in the base material, in which, in an X-ray diffraction analysis pattern using a Cu-Kα ray, in a case in which peak intensity corresponding to the α-type sialon phosphor having a diffraction angle 2 θ in a range of 30.2° or more and 30.4° or less is defined as I.sub.α and peak intensity of a peak having a diffraction angle 2 θ in a range of 26.6° or more and 26.8° or less is defined as I.sub.β, I.sub.α, and I.sub.β satisfy 0<I.sub.β/I.sub.α≤10.