Abstract: The invention relates to polycarbonates suitable for use in optical articles, and methods for making such polycarbonates. The polycarbonates may comprise residues of m,p-BPA and SBI.

Abstract: A method and catalyst system for producing aromatic carbonates from aromatic hydroxy compounds. In one embodiment, the method includes the step of contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system having an effective amount of a cobalt source in the absence of a Group VIII B metal source. In various alternative embodiments, the carbonylation catalyst system can include at least one inorganic co-catalyst, as well as a halide composition and/or a base.

Abstract: A method of making an evaporated deposit of a material comprising the steps of: (i) positioning at least one test substrate above a vapor source wherein at least a portion of the at least one test substrate is not perpendicularly disposed to vapor source, (ii) heating the vapor source in a vacuum to evaporate the vapor source, (iii) condensing a deposit evaporated from the vapor source on the at least one test substrate such that at least a portion of the deposit is not perpendicularly deposed to the vapor source, (iv) measuring the chemical composition of the deposit at various positions relative to a line normal to the vapor source, (v) repeating steps (i) through (iv) until a deposit having a desired chemical composition is measured, (vi) removing each of the at least one test substrate, (vii) positioning a workpiece above the vapor source at a location corresponding to that of the test substrate upon which a deposit of desired chemical composition is condensed and measured, (viii) heating the vapor source

Abstract: The present invention, in one form, is a system for reducing contribution of scatter signal to an image of an object constructed from projection data acquired during a computed tomography scan. The system includes an x-ray source which emits an x-ray beam toward a detector array. A collimator plate is movable with respect to the detector array. The system is configured to move the collimator between a first position and a second position. In the first and second positions, the collimator does not cover the detector array, i.e., the collimator does not collimate the x-ray beam impacting the detector array. When moving between the first and second positions, the collimator at least partially covers the detector array, i.e., the collimator at least partially collimates the x-ray beam impacting the detector array.

Abstract: A method and catalyst system for producing aromatic carbonates from aromatic hydroxy compounds. In one embodiment, the method includes the step of contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system having an effective amount of a manganese source in the absence of a Group VIII B metal source. In various alternative embodiments, the carbonylation catalyst system can include at least one inorganic co-catalyst, as well as a halide composition and/or a base.

Abstract: A collimator 100 for use in a radiation imaging system 10, and a method for making such collimators, are provided, wherein the collimator 100 is capable of collimating radiation in two orthogonal planes. The collimator in one embodiment includes a block 101 of radiation absorbing material having a plurality of focally aligned channels 102 extending therethrough; in a second embodiment, the collimator includes first and second collimation204, 212 sections having a respective first plurality of focally aligned plate sets 201 and a respective second plurality of focally aligned plate sets 203 disposed orthogonally to the first plurality of plate sets. The method for making the collimator includes generating a CAD drawing, generating from the CAD drawing one or more stereo-lithographic files, and using the stereo-lithographic files to control an electro-deposition machining machine which creates the channels in the block.

Abstract: A method for improving the overall power rating and thermodynamic efficiency of a steam and gas turbine combined cycle plant having a conventional heat recovery steam generator (“HRSG”) as part of the bottoming cycle by cooling the inlet air to the gas turbine (particularly under circumstances when the ambient inlet air temperature to the gas turbine exceeds about 60° F.) using an external chiller subsystem.

Abstract: A source applies imaging energy that passes through an object being imaged and is then detected by a detector. A scanning trajectory causes the detector to provide measured cone beam data to a processor. The measured cone beam data is over a characteristic surface with a corresponding characteristic problem. The processor solves the characteristic problem such that missing cone beam data is determined. The measured cone beam data and the determined cone beam data together provide a complete data set for exact image reconstruction.

Abstract: A radiation imager includes a photosensor array that is coupled to a scintillator so as to detect optical photons generated when incident radiation is absorbed in the scintillator. The imager further includes a robust protective cover that is disposed over the scintillator to seal the scintillator from exposure to ambient moisture. The protective cover has a three panel laminate structure including a pair of first-type material panels with a second-type material panel disposed therebetween. In one embodiment, the protective cover includes a lower hermetic barrier layer, an intermediate structural layer, and upper hermetic barrier layer. The upper and lower hermetic barrier layers are of the same material; the intermediate structural layer comprises a composite material having an adhesive impregnated therein.

Abstract: Controlled generation of ozone is provided by flowing air around an electrodeless low pressure discharge lamp having high ultraviolet transmission properties. Power to the lamp is controlled by a circuit that is driven by a photocell for detecting visible light emissions from a phosphor triggered by ultraviolet radiation from the lamp upon the phosphor.

Abstract: Hydroxyaromatic compounds such as phenol are carbonylated with oxygen and carbon monoxide in the presence of a catalyst system comprising a Group VIIIB metal, preferably palladium; an alkali metal or alkaline earth metal halide, preferably sodium bromide; and a promoter compound which is at least one C2-8 aliphatic or C7-10 aromatic mono- or dinitrile, preferably acetonitrile or adiponitrile. The catalyst system also preferably contains a compound of a non-Group VIIIB metal, preferably lead.

Abstract: A magnet, such as an open magnetic-resonance-imaging (MRI) magnet) has a first assembly including a superconductive main coil and a magnetizable pole piece which, during magnet operation, has a temperature equal to generally the temperature of the main coil. In one example, a cryogenic-fluid (e.g., liquid helium) dewar encloses the main coil, and the dewar has an interior surface defined in part by a surface portion of the pole piece. A method for providing a homogeneous imaging volume for a magnet includes steps to construct the above-described magnet.

Abstract: A method and apparatus for detecting motor contamination utilizes zero-sequence currents in a sensing coil to detect contamination. The detector includes a current transformer comprised of a magnetic core and a sensing coil wound about the core. A processor processes a sub-trip level current from the sensing coil to detect contamination. Three contamination detection methods, which may be used separately or in desired combination, are based on current trends, current leakage, and current clustering. An alarm is triggered when predetermined alarm criteria have been met.

Abstract: A coating is applied to reinforcing fibers arranged into a tow by coaxially aligning the tow with an adjacent separation layer and winding or wrapping the tow and separation layer onto a support structure in an interleaved manner so that the separation layer separates a wrap of the tow from an adjacent wrap of the tow. A coating can then be uniformly applied to the reinforcing fibers without defects caused by fiber tow to fiber tow contact. The separation layer can be a carbon fiber veil.

Abstract: An ignition system for a gas appliance comprises an ignitor for igniting gas, a gas valve which controls the flow of gas to the ignitor, and a delay switch which delays the opening of the gas valve. The delay switch comprises a piston and a cylinder which define a chamber. The piston moves between a first position and a second position in the cylinder. The piston is coupled to the gas valve such that when the piston reaches the second position, the gas valve is opened. The chamber includes a large aperture and a small aperture which influence the rate at which the piston moves. The large aperture includes a sealing member which seals the large aperture when the piston moves from the first position to the second position to resist the motion of the piston. The large aperture is opened when the piston moves in the other direction. The delay switch is connected to the ignitor such that when the ignitor is turned on, the piston moves against air resistance and delays the opening of the gas valve.

Abstract: A method for generating a high resolution image in a radiation imaging system which produces multiple exposure signals from a movable detector array is disclosed. The image data signals or image acquisition signals generated from the image detector assembly of the image radiation system during an imaging cycle are passed through a finite impulse response filter having a combined frequency response comprised of an inverse filter frequency response portion and a noise regularization frequency response portion such that the noise regularization decrease the frequency response of the filter as the frequency of the data signals increase thereby effectively preventing blurring of the image produced from the image data signals.

Abstract: A plurality of low-voltage, series-connected input dc-dc converters provide the input to a low-frequency, high-voltage dc-ac output bridge converter suitable for driving a gradient coil in an MRI system. The relatively low-voltage, series-connected dc-dc converters, or choppers, control the gradient coil current, while the dc-ac converter bridge steers the current to the proper coil polarity. A binary weighting of the voltage ratings of the input choppers results in the lowest voltage unit doing most of the high-frequency switching. Such an amplifier configuration is modular and allows for different gradient coil requirements to be met with a common approach by applying a predetermined number of choppers and bridges.

Abstract: A magnet pole piece assembly has first and second pole pieces and at least one support member. The pole pieces have longitudinally aligned and facing surface recesses. The support member has a central segment and first and second end segments abuttingly and metallurgically attached to the central segment. The first and second end segments are positioned within a corresponding surface recess of the first and second pole piece and are abuttingly and metallurgically attached to the corresponding pole piece. An open magnet adds main coils to the magnet pole piece assembly.

Abstract: An article is described, which includes a metal-based substrate, such as a superalloy; a dense, primary bond layer; and a spongy secondary bond layer. A thermal barrier coating is applied over the secondary bond layer. The spongy layer has a microstructure which includes an open network of interconnected pores. A process is also described. It includes the step of applying a spongy, metallic bond layer over the substrate, followed by the application of a thermal barrier coating. A dense, primary bond layer may optionally be applied before the application of the spongy layer.

Abstract: In an exemplary embodiment, the apparatus includes an electromagnetic radiation source, an optical analyzer, and a fiber optic bundle. The fiber optic bundle has an excitation fiber in optical communication with the electromagnetic radiation source and a plurality of emission fibers in optical communication with the optical analyzer. The optical analyzer can have multiple channels, including a fluorescence-emission channel in optical communication with the emission fibers. Optionally, the fiber optic bundle can further contain at least one reflection fiber in optical communication with an absorbance/reflectance channel. In addition to detecting Fries product in formed polycarbonate materials, the method and apparatus can also be utilized to directly determine the concentration of a target species in parallel polycarbonate reactor systems.