Abstract: Cerium-doped alkaline-earth hafnium oxide scintillator compositions have at least one alkaline earth metal selected from the group consisting of Ba, Sr, Ca, and combinations thereof. The scintillator compositions can be formed into a shape having porosity less than about 0.05 percent for improved transparency. The alkaline earth metal can be partially substituted with divalent and/or trivalent ions other than cerium. Hafnium can be partially substituted with divalent, trivalent, and/or tetravalent ions. The scintillators are characterized by high light output, short decay time, and high radiation stopping power. The scintillators can be used as detector elements in PET systems.

Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members.

Abstract: A ceramic discharge chamber for a lamp, according to an exemplary embodiment of the invention, comprises a first member which includes a leg portion and a transition portion, wherein the leg portion and the transition portion are integrally formed as one piece from a ceramic material, and a second member which includes a body portion, wherein the body portion is bonded to the transition portion of the first member. The ceramic discharge chamber can be formed by injection molding a ceramic material to form the first member, the first member forming a first portion of the ceramic discharge chamber; and bonding the first member to a second member which forms a second portion of the ceramic discharge chamber. The members which form the ceramic discharge chamber can greatly facilitate assembly of the discharge chamber, because the discharge chamber can be constructed with only one or two bonds between the members.

Abstract: An article protected by a thermal barrier coating system includes a substrate having a substrate surface, and a thermal barrier coating system overlying the substrate. The thermal barrier coating system has a thermal barrier coating formed of a thermal barrier coating material arranged as a plurality of columnar grains extending generally perpendicular to the substrate surface and having grain surfaces. A sintering inhibitor is within the columnar grains, either uniformly distributed or concentrated at the grain surfaces. The sintering inhibitor is lanthanum oxide, chromium oxide, and/or yttrium chromate, mixtures thereof, or mixtures thereof with aluminum oxide.

Abstract: A scintillator pack comprises an array of scintillator pixels and an x-ray absorbing layer disposed in inter-scintillator regions between the scintillator pixels. The x-ray absorbing layer acts to absorb x-rays and protect underlying regions of the inter-scintillator regions. The x-ray absorbing layer may be formed by a number of methods including casting and melt infiltration.

Abstract: A scintillator pack comprises an array of scintillator pixels and an x-ray absorbing layer disposed in inter-scintillator regions between the scintillator pixels. The x-ray absorbing layer acts to absorb x-rays and protect underlying regions of the inter-scintillator regions. The x-ray absorbing layer may be formed by a number of methods including casting and melt infiltration.

Abstract: A scintillator pack comprises an array of scintillator pixels and an x-ray absorbing layer disposed in inter-scintillator regions between the scintillator pixels. The x-ray absorbing layer acts to absorb x-rays and protect underlying regions of the inter-scintillator regions. The x-ray absorbing layer may be formed by a number of methods including casting and melt infiltration.

Abstract: A matching layer for ultrasound transducers has a gradient in impedance value from one surface to the other surface of the matching layer. The matching layer is composed of a plurality of sublayers made of composite materials and securely attached together and is disposed on the surface of the transducer element. The first sublayer adjacent to the transducer element has an impedance value less than or equal to that of the transducer element. The last sublayer adjacent to the target has an impedance value greater than or equal to that of the target. The impedance values of the sublayers decrease monotonically from the first to the last sublayer.

Abstract: Acicular bodies of a metal compound are produced by slowly precipitating an organic salt of the metal from a solution of an ester of a dicarboxylic acid having 1-5 carbon atoms and firing the precipitate in an oxidizing atmosphere. These acicular bodies have a cross-sectional dimension less than about 20 &mgr;m and are useful for providing reinforcement of a larger ceramic body. Acicular bodies of rare-earth metal oxides also are useful in reinforcing x-ray scintillator bodies without diminishing their luminescent capacity.

Abstract: The invention relates to a method of forming a composite article comprising the steps of forming a plurality of green ceramic elements, wherein the green ceramic elements are arranged side by side, and the green ceramic elements are spaced from each other by gaps; filling the gaps with a second material; and sintering the green ceramic elements with the second material to form the composite article. The second material, after being sintered, acts as a reflector layer to prevent substantially all light in one of the sintered ceramic elements from reaching an adjacent sintered ceramic element. The step of filling the gaps may be carried out by forming a slurry containing the second material in powder form and immersing the green ceramic elements in the slurry. The process of cosintering the green ceramic elements with the reflector composition provides improved dimensional control during sintering and reduces processing costs.

Abstract: A curable masking material for protecting a passage hole in a metal-based substrate is formed of an extrudable resin composition. The resin composition is thermally stable at elevated temperatures, and does not serve as an adhesion site for any coatings which are applied over the masking material. In addition, the resin composition has non-Newtonian flow characteristics and is adapted to form a protrusion extending from the passage hole upon extrusion to fill the passage hole.

Abstract: A method for temporarily protecting at least one passage hole in a metal-based substrate from being obstructed by at least one coating applied over the substrate is disclosed.

Abstract: Polymer compositions comprising polysiloxanes and metal coated boron phosphates are described and they unexpectedly display flame retardant properties and hydrolytic stability without creating environmental hazards.

Abstract: An infrared energy reflecting enamel composition comprises a ground coat of enamel on a substrate and embedded TiO.sub.2 particles in the ground coat of enamel. The infrared reflecting enamel composition has an infrared energy reflectivity value of at least 80%. A method for manufacturing the composition is also disclosed for embedding the TiO.sub.2 in the enamel.

Abstract: A method for temporarily protecting at least one passage hole in a metal-based substrate from being obstructed by at least one coating applied over the substrate is disclosed. The method includes the following steps:(a) filling and covering the hole with a curable masking material which forms a protrusion over the hole;(b) curing the masking material;(c) applying at least one coating over the substrate and the masking material, wherein the coating does not substantially adhere to the protrusion; and then(d) removing the masking material to uncover the passage hole.Usually, there are an array of holes, and they serve as conduits for cooling gasses for an engine component. The curable masking material exhibits substantially non-Newtonian flow characteristics which make it especially suitable for forming protrusions of the proper size and shape on the coating-side of an engine part.

Abstract: An infrared energy cooking and heating apparatus comprises an infrared layer or reflective coating, particularly on inner panels of ovens or other cooking devices. The coating is preferably an enamel and reflects the infrared energy to the food being cooked and heated. In particular, the infrared cooking apparatus are substantially faster than such processes in conventional ovens, and offer improvements in foodstuff cooking times. The enamel comprises metal oxide particles that enhance the infrared energy reflectivity of the enamel. Further, the metal oxide particles in the enamel can be formed in several ways so as to enhance the reflectivity.

Abstract: A method for fabricating "1.5D" and "2D" multilayer ultrasonic transducer arrays employs dicing saw kerfs, which provide acoustic isolation between rows. The kerfs are metallized to provide electrical connection between surface electrode layers and buried internal electrode layers. A multilayer piezoceramic transducer element for a "1.5D" or "2D" array produced by this method has higher capacitance, and accordingly provides better transducer sensitivity, in comparison to a single layer element.

Abstract: A method of fuel gas desulfurization comprises the steps of introducing fuel, such as coal, into a gasifier, heating the fuel in the gasifier to a temperature so as to form a gaseous fuel mixture containing sulfur compounds, and conveying the gaseous fuel mixture over a sulfur absorbing and surface-catalyzing zinc-based sorbent that catalyzes an exothermic reaction to locally increase the surface temperature of the sorbents, thereby enhancing the rate of desulfurization. Additionally, in accordance with the instant invention, the sulfur absorbing and surface-catalyzing zinc-based sorbent comprises a chemical composition of a metal selected from the group consisting of iron, cobalt, and molybdenum that catalyzes an exothermic reaction at the sorbent surface and an inert metal selected from the group consisting of titanium, zirconium, cerium and hafnium for desulfurization.

Abstract: A method for fabricating "1.5D" and "2D" multilayer ultrasonic transducer arrays employs dicing saw kerfs, which provide acoustic isolation between rows. The kerfs are metallized to provide electrical connection between surface electrode layers and buried internal electrode layers. A multilayer piezoceramic transducer element for a "1.5D" or "2D" array produced by this method has higher capacitance, and accordingly provides better transducer sensitivity, in comparison to a single layer element.

Abstract: A metal borate, metal phosphate or metal borophosphate in combination with either a metal sulfide or sulfur polysiloxanes are incorporated into polymer systems to produce a polymer composition which unexpectedly displays flame retardant properties without creating environmental hazards.