Abstract: A polycrystalline article is converted to a single crystal in a solid-state process. Heat is applied at a first end of the article to effect a predetermined spatial temperature profile thereat having a maximum temperature approaching a melting temperature thereof. The temperature profile is maintained to initiate conversion at the first end. The heat is moved along the article toward an opposite second end to correspondingly propagate the conversion along the article.

Abstract: Dovetail seals are quickly and inexpensively applied to turbine buckets or rotor disks by ultrasonically welding a piece of material onto the dovetail portion of the bucket or the disk slot of the rotor disk. The method includes placing the piece of material into contact with the appropriate turbine structure and applying a compressive force so as to press the piece of material against the turbine structure. Ultrasonic energy is then applied to the piece of material so as to ultrasonically weld it to the turbine structure.

Abstract: A scintillator pack including an x-ray damage shield. The scintillator pack has an array of scintillator pixels. A scintillation light reflecting layer that reflects scintillation light from the pixels is included at least between the scintillator pixels in inter-scintillator regions. An x-ray absorbing layer acts as the x-ray damage shield to protect the portions of the scintillation light reflecting layer from x-rays. The x-ray absorbing layer is formed selectively and in a self aligned manner in regions over the inter-scintillator regions.

Abstract: A brush seal segment useful, when circumferentially arrayed with other such segments, to seal the gap between a rotor and a surrounding casing of a rotary machine such as a gas or steam turbine. Brush-seal bristles are positioned between a brush-seal back plate and a brush-seal front plate with the free end of each bristle extending beyond the edges of the plates. The front plate has a portion extending to the edge of the front plate with the portion spaced apart from the bristles. In one example, the portion has an array of through holes. In another example, the portion has a ledge projecting generally away from the bristles.

Abstract: An apparatus and method for sensing touch between a compression mold and a workpiece located in the compression mold including a mold cavity and a mold closure movable relative to the workpiece. The apparatus may include at least one touch sensor pad positionable to signal touch between the mold closure and the workpiece. The touch sensor pad may be in communication with a touch sensor monitor for indicating touch between the workpiece and the mold closure. The touch sensor pad may also be embodied in a touch sensor assembly.

Abstract: A VAR process is conducted in an apparatus characterized by a crucible wall that provides a stable shelf anchor. The VAR apparatus includes a furnace chamber, a consumable electrode formed of a material to be remelted within the furnace chamber and a crucible within the furnace chamber. The crucible has a wall that forms a vessel to collect melt material from the consumable electrode. At least part of the wall is textured to provide area for mechanical stabilization of the shelf as the underside of the shelf melts and the upperside of the shelf forms. In a vacuum arc remelting process, a consumable electrode is loaded into a furnace chamber above a cooled crucible having a textured wall that forms a vessel to collect melt material from the consumable electrode. The process includes striking a direct electric current between the electrode and a bottom of the crucible to cause melting of material from a tip of the electrode. Melt material is collected from the tip in the crucible.

Abstract: A method for smoothing the surface of a ceramic-based protective coating which exhibits roughness is disclosed. The method includes the steps of applying a ceramic-based slurry or gel coating to the protective coating surface; heating the slurry/gel coating to remove volatile material; and then further heating the slurry/gel coating to cure the coating and bond it to the underlying protective coating. The slurry/gel coating is often based on yttria-stabilized zirconia, and precursors of an oxide matrix. Related articles of manufacture are also described.

Abstract: An electrochemical machine is disclosed for use in an electrochemical machining process to simultaneously generate different levels of metal removal. The electrochemical machine comprises at least two electrodes, each including an electrically conductive cylinder having an external surface partially coated with an insulated coating. The insulating coating is in a pattern defining raised areas to be formed on an internal surface of a predrilled hole in a workpiece wherein at least one of the electrodes has a varied pattern of insulating coating.

Abstract: This invention provides a method for preparing polycarbonates, which utilizes polycondensation catalysts which are salts of macrocyclic polypyrroles with the general formula Ax+y[(Porphine−Tm)By−x] or Ax+y[(Phthalocyanine−Tm)By−x], where A is certain alkali metals, B contains a charge balancing sulfonate, carboxylate, or phosphonate group and Tm is a transition metal are useful as polycarbonate melt polymerization catalysts. We have found that this new class of catalysts provide excellent polymerization rates for the preparation of Bisphenol A polycarbonate from the melt polymerization of diphenyl carbonate and Bisphenol A. Moreover, the catalysts of the invention were found to be very selective in substantially reducing the level of branching side reaction, i.e., formation of Fries product, normally associated with the melt polycarbonate process.

Abstract: An N-VSB (vestigial sideband) modulation signal is converted into an M-QAM (quadrature amplitude modulation) signal, where M=N2, by shifting the symbol rate frequency of a received N-VSB modulation signal to center the waveform spectrum about zero Hertz prior to complex demodulation so that data symbols will alternately appear on demodulated I and Q channels. A pilot tone of the received N-VSB modulation signal is removed to eliminate any bias in the both I and Q channels. Symbol timing between I and Q channels is offset, and quadrature amplitude demodulation of the I and Q channel signals generate alternating I and Q channel data symbols. Alternating inversion of the alternating I and Q channel data symbols recovers the N-VSB symbol data.

Abstract: A caul is used in an autoclave process for consolidating a composite, multi-ply, gas turbine fan blade preform having first and second opposite sides and a varying thickness therebetween. The caul includes a body having fibers situated in a matrix. The caul is complementary in shape to the preform first side and has a bending flexibility varying over the body for correspondingly varying consolidation of the preform. The second side of the preform is shaped by a bottom mold in the autoclave chamber.

Abstract: A method and apparatus are provided which utilize a circular tomosynthesis system to collect 2-D x-ray projection radiograph data of an object being evaluated. The collected data is then transformed into a form suitable for cone beam volumetric computed tomography (cone beam VCT) reconstruction. Once the data has been transformed, a cone beam VCT reconstruction algorithm may be utilized to reconstruct a 3-D image of the object.

Abstract: The flowrate of a stream discharged from a drain in a vessel is measured by imaging the stream, measuring a diameter of the stream image, and calculating the flowrate based on the measured diameter. A video camera may be aimed below the drain for imaging the stream. A computer is joined to the camera for measuring the diameter of the stream and calculating a corresponding flowrate therefor.

Abstract: A continuously-graded bond coat comprises a gradient of at least one material characteristic value. The gradient extends from a first material characteristic value at a first surface region to a second material characteristic value at a second surface region. The continuously-graded bond coat can be used in a thermal barrier coating system. A source ingot for forming the continuously-graded bond coat comprises aluminum, in an atomic percent range from about 50.0 to less than about 100.0; chromium in an atomic percent range from about 5.0 to about 40.0; silicon in an atomic percent range from about 1.0 to about 17.0; zirconium in an atomic percent range from about a trace to about a 0.5, yttrium in an atomic percent range from a trace to about 2.0; and hafnium in an atomic percent range from about 0.5 to about 2.0. A method for forming the continuously-graded bond coat with the gradient is also provided by the invention.

Abstract: An MRI system repeatedly performs a pulse sequence during a time interval &Dgr;T in which a surge of blood flows through a vessel whose compliance is to be measured. Two spaced-apart slices are simultaneously excited by each pulse sequence and the transverse magnetization is flow-encoded before an NMR signal is acquired in the presence of a readout gradient pulse. The change in phase of the NMR signal is used to detect when the wave arrives at each slice location, and from this information blood vessel compliance may be calculated.

Abstract: A wetting balance includes a load cell for suspending a specimen above a crucible containing a molten braze pool. A lift supports the crucible for vertical lifting thereof to effect an immersion cycle of the specimen in the pool. A controller operates the lift and determines first contact with the pool by measuring force changes thereat and produces a measured force log during the immersion cycle. In operation, the lift is operated for a predetermined time following first contact for immersing the specimen to a predetermined depth in the pool.

Abstract: The invention provides a transmitter and a signal for communicating information via a power line. The signal comprises a superset and the superset comprises a plurality of tone sets.

Abstract: A method for making a brush-tooth seal, such as a brush-tooth seal which is attachable to a turbine stator, includes obtaining a seal carrier having a groove and having seal teeth and obtaining a brush seal having bristles with tips. The brush seal is engaged in the groove and then attached to the seal carrier. Then, the tips of the bristles of the attached and engaged brush seal are cut, such as with an electric discharge machining (EDM) wire, at a predetermined distance from the longitudinal axis of the seal carrier.

Abstract: A splice connector includes a first coupling electrically connected to a first cable or conductor and a second coupling electrically connected to a second cable or conductor. Both couplings include at least one electrically conductive spade. The second coupling engages the first coupling so that the respective spades contact each other, thereby electrically connecting the two cables or conductors. Due to its construction and mass, this connector can be used in high temperature, high-G environments.

Abstract: In dual line ultrasound beamforming, an ideal transmit beam should have two peak locations, each following one of the receive beams. Dual beam steering by apodization creates such transmit beam; however, the resulting beam is optimized for only a single depth and significant line warping can occur away from that depth. The transmit beam shape in ultrasound multiline acquisition however, is improved by numerically optimizing the transmit beam, i.e., the aperture function, such that no line warping occurs over the entire depth of field. The aperture function is numerically optimized by numerically optimizing a Cost function which is dependent on the aperture function. The numerically optimized aperture function is then used in a multiline acquisition mode of an ultrasound imaging system.