Abstract: A hermetic, high current package for a semiconductor device includes wide flat leads which are bonded to the contact pads of the device and formed to extend through apertures in an insulating lid. The lid is sealed to a base and the apertures around the leads are sealed with solder to provide the hermetic package. This package limits lateral current flow in the contact pads of the semiconductor device to relatively low levels which ensure the integrity of the contact pads.

Abstract: The emulsion polymerization of a mixture of organic silicon monomers and vinyl containing organic monomer is effected substantially concurrently. Flocculation of the emulsion polymerized material, and recovery of the flocculated material has been found useful in providing multi-lobed impact modifiers for a variety of organic thermoplastic polymers.

Abstract: A method and apparatus for indirectly determining rotor position in a switched reluctance motor (SRM) are based on a flux/current model of the machine, which model includes multi-phase saturation, leakage, and mutual coupling effects. The flux/current model includes a network mesh of stator, rotor and air gap reluctance terms. The network is driven by magnetomotive force (mmf) terms corresponding to the ampereturns applied to each of the stator poles. Phase current and flux sensing for each phase are performed simultaneously. The reluctance terms of the flux/current model are determined from the phase flux and current measurements. The phase current and flux measurements also determine the rotor position angle relative to alignment for each respective motor phase and which phase (or phases) is operating in its predetermined optimal sensing region defined over a range of rotor angles.

Abstract: A liquid crystal display device includes an entrance polarizer to provide light which is linearly polarized in a first selected direction and a first birefringent film to convert the linearly polarized light from the entrance polarizer to elliptically polarized light having a selected ellipticity. At least one liquid crystal cell having an ellipticity equal to the selected ellipticity receives the light propagating from the first birefringent film; the liquid crystal cell includes first and second parallel-facing transparent plates which sealably contain a quantity of liquid crystal material. The liquid crystal material comprises at least a first molecule immediately adjacent the first transparent plate which is oriented in the first selected direction and at least a second molecule immediately adjacent the second transparent plate which is oriented in a second selected direction.

Abstract: A passive, resonant starting circuit for an electrodeless HID lamp includes a starting coil that is shielded from stray capacitances that would otherwise result in detuning the resonant circuit and hence decreasing efficiency. The starting circuit further includes a capacitance coupled in series with the starting coil and another capacitance coupled in parallel with the coil. In a preferred embodiment, the starting coil is enclosed in a conductive cylindrical housing which functions as both a shield from external capacitances and the resonant capacitance in parallel with the starting coil. The housing has a lengthwise gap in order to prevent the housing from acting as a short circuit secondary with respect to the starting coil. A conductive disk is mounted to the ground end of the housing to increase shielding even further. The parallel resonant capacitance is determined by the length of the housing and the distance between the coil and the housing.

Abstract: The present invention is a method for forming an electrode-lead assembly. In one embodiment, the method comprises the steps of aligning the energy outlet of an energy source with an end portion of the lead, operating the energy source so that the emitted energy heats the end of the lead and so that a melt is formed at the end portion of the lead, and allowing the melt to solidify. The solified melt is bullet-shaped and serves as an electrode.

Abstract: A technique that reconciles the differences between the estimator and the filter of a multi-pulse linear predictive voice encoder achieves a higher quality in the output speech. The technique simultaneously solves for the pulse amplitudes and pitch tap gain to minimize the estimator bias in the multi-pulse excitation and thereby improves, performance of the system. The increased signal-to-noise ratio is accomplished by first modifying the pitch predictor such that the pitch synthesis filter accurately reflects the estimation procedure used to find the pitch tap gain and, second, improving the excitation analysis technique such that the pitch predictor tap gain and pulse amplitudes are solved for simultaneously, rather than sequentially. Neither of these modifications results in an increased transmission rate and they do not significantly increase the complexity of the multi-pulse coding algorithm.

Abstract: Thermoplastic sheets are provided such as polymethylmethacrylate sheets and polycarbonate sheets which exhibit improved water wetting and water spreading characteristics. A method for making such articles is also provided which can be employed to make the thermoplastic structured sheets useful in greenhouses and for other roofing and glazing applications such as sun glasses and ski goggles.

Abstract: Conductive patterns may be formed on the surface of thermally inefficient substrates by depositing a uniform layer of metal thereover whose upper surface is substantially UV light absorbing followed by laser ablation of the deposited metal to leave the deposited metal only in the desired metal pattern. Thermally efficient substrates may be rendered thermally inefficient by the deposition of a thermally inefficient material thereon. That thermally inefficient material may be either electrically insulating or a metal. A two layer metallization comprising a first, thermally inefficient reactive metal and a second UV light absorbing metal is preferred. When disposed on a thermally inefficient substrate, this two layer metallization ablates reactively as the two layers burn off together. This laser ablation process substantially roughens the surface of polymer dielectrics and may be used to repair open traces in printed circuit structures.

Abstract: A. parasiticus is employed to hydroxylate 2'-hydroxyterphenyl compounds to terphenyltriols, which can be used to form branched polycarbonates. The hydroxylation reaction is enhanced by maintaining a sufficient amount of a carbon source in the culture medium-reaction medium to maintain the ammonium level below 300 ppm. during the bioconversion phase. Employment of a mutant strain of A. parasiticus which was isolated following ultraviolet light mutagenesis to reduce its tendency to produce aflatoxins is preferred.

Abstract: Photoresist layers are rapidly exposed in a pattern determined by electronically stored data by exposure of the photoresist through a high resolution liquid crystal shutter array.

Abstract: A Gifford-McMahon cryorefrigerator is modified by using opposed sub-displacers which are sinusoidally reciprocated in opposite directions with respect to one another such that the force vectors of inertia created by the movement of the sub-displacers are cancelled out. The cancelling out of the force vectors should substantiallly reduce adverse affects associated with displacer banging.

Abstract: In a gas burner assembly, the gas burners are equipped with a device constructed of a thermostatic, bimetallic material which autoregulates the amount of primary air that can be entrained into the burner such that the likelihood of an occurrence of lifting or flashback is substantially reduced, and elevated CO emissions at reduced firing rates are eliminated.

Abstract: A refrigeration system suitable for use in household refrigerators having a fresh food compartment, a freezer compartment and an intermediate temperature compartment is provided. The system includes a first expansion throttle, a first evaporator for providing cooling to a freezer compartment, first, second and third compressors, a condenser, a second expansion throttle, a second evaporator for providing cooling to a fresh food compartment, a third expansion throttle, and a third evaporator for providing cooling to an intermediate compartment. All the above elements are connected in series, in that order, in a refrigerant flow relationship. A first phase separator connects the second evaporator to the third expansion throttle in a refrigerant flow relationship and provides intercooling between the second and third compressors.

Abstract: An inline splicing system for brittle conductors which is comprised of a superconductor core, a superconductor coil having a length of conductor wound upon it with a terminal end, a supply spool of compatible conductor having a terminal end, both conductors being in an abutting relationship for a prescribed length, a spacer located between a portion of the abutting length and the core, and a soldering means which creates a solder along the abutting length that conforms to the circular surface of the core.

Abstract: Silicone polyimides resulting from the condensation of para phenylene diamine and an organic dianhydride mixture of a bis(phthalic anhydride)poly(diorganosiloxane), a 2,2 bis[4-(3,4-dicarboxyphenoxy)phenyl] propane dianhydride and hydroquinone dianhydride in a dipolar aprotic solvent have been found to be substantially insoluble in chlorinated organic solvents such as chloroform and useful as melt extrudable wire coating compositions.

Abstract: A fuel with or without fuel bound nitrogen (FBN) is burned in a high pressure machine (20 atm) comprising fuel and air compressors, combustor and turbine at an ER of about 2-3 and temperature below the threshold for creating thermal NO.sub.x. Prompt and FBN NO.sub.x are avoided due to the rich mixture, having a dearth of O and OH, producing CO and H.sub.2 and little CH. The turbine cools the products to reduce their temperature. The cooled products are mixed with the remaining air and burned at a temperature below the thermal NO.sub.x threshold temperature at an ER of about 0.6. Commercial stand alone machines can be used for the rich and for the lean combustors wherein air and fuel are supplied to the rich combustor and only air and the cooled combustion products of the rich machine are supplied to the lean combustor.

Abstract: A gradient current speed-up circuit, for use in a higher-speed NMR imaging system having an associated gradient coil, has a gradient power amplifier receiving an input analog signal controlling the current in an amplifier output circuit connected in series between first and second portions of a single gradient coil. Semiconductor switching elements selectively connect the coil portion-amplifier-coil portion between first and second potential sources, and are turned on and off in selected patterns to cause a current to be suddenly applied to, and removed from, flow through the associated gradient coil and the amplifier output circuit.

Abstract: A method for contraction annealing niobium-tin wire is disclosed. An improved niobium-tin wire is provided by loosely winding the wire on a mandrel, or by coiling the wire on a circumferentially retractile mandrel, and contraction annealing the wire without reaction-forming substantial amounts of Nb.sub.3 Sn. Such contraction annealing allows the wire to contract in length unconstrained thereby preventing the formation of internal tensile stresses in the wire and its surrounding insulation. Prevention of internal stresses in the wire greatly reduces the susceptibility of the wire to breakage, cracking, sintering, shorting, tin leakage, or substantial shifting of the wire from desired wrap positions when it is reaction annealed to form the brittle super-conducting intermetallic compound Nb.sub.3 Sn.

Abstract: Gamma titanium aluminide alloys can be melted by a method comprising, melting a charge comprised of the titanium aluminide alloy and an effective amount of a metal from the group consisting of niobium, tantalum, tungsten, and molybdenum to reduce oxygen pickup in the melt, the melting being performed in a calcia crucible.