Abstract: A starting circuit for an electrodeless HID lamp, comprising a series resonant LC circuit of variable impedance, provides a starting voltage to a fixed or movable starting probe substantially simultaneously with the application of power to the excitation coil from the main power source. In a preferred embodiment, the starting circuit provides a starting signal to a gas probe starter of the type including a fixed starting electrode coupled to a starting chamber which contains a relatively low-pressure gas and is attached to the outer wall of the arc tube. Resonant operation of the starting circuit results in the application of a sufficiently high voltage to ignite a glow discharge in the low-pressure starting chamber. In turn, the starting voltage is capacitively coupled to the arc tube, ionizing the fill and initiating an arc discharge therein.

Abstract: A hermetically sealed package for a semiconductor device includes a lid through which the leads of the device extend vertically away from the chip through an aperture in the lid which is hermetically sealed by the external terminal or electrode. The package is compact, lightweight and free of magnetic materials.

Abstract: An oversampling converter of a type using a plural-order, plural-stage sigma-delta modulator, the output signal to the decimating filter of which modulator has the quantization noise contribution of a number of its plurality of stages suppressed therein, uses single-bit quantization in those stages to help avoid problems of nonlinearity. Each other sigma-delta converter stage, the quantization noise of which appears in substantial amount in the converter output signal to the decimating filter, uses quantization having multiple-bit resolution to help increase the resolution of the oversampling converter overall.

Abstract: Cyclic polycarbonate oligomers are polymerized by ultrasonic cavitation, either using a positive pressure of the ultrasonic probe or in combination with the action of at least one cyclic polycarbonate oligomer polymerization catalyst. Polymerization by this method may be effected on neat cyclic polycarbonate oligomers or on mixtures thereof with reinforcing agents such as glass fibers.

Abstract: A method and apparatus for filling generally cylindrical molds with powder particles is disclosed. A stream of powder particles is fed into a mold, and the powder particles are compacted in spirally formed layers so that the particles are compacted continuously in localized adjacent areas. The powder filling apparatus is comprised of a blade means configured to direct powder particles to spread evenly in the mold and urge the powder particles to compact while the blade means is rotated about an axis. A shaft is attached to the blade means for rotation of the blade means about the axis. A chuck means is slideably mounted on the shaft means through an axial channel, the chuck means being configured for applying force to the shaft while permitting movement of the shaft axially through the channel. A drive means is operatively connected to the chuck means for applying force to rotate the chuck about the axis.

Abstract: A composite structure comprising a symmetric bimetallic laminate bonded to a separate substrate is provided by eutectic bonding the bimetallic laminate to the substrate. A variety of beneficial structures can be provided.

Abstract: Copolymer-containing compositions are prepared by the reaction of an epoxytriazine-capped polyphenylene ether with another polymer containing amine end groups, especially a polyamide, under intimate blending conditions. The compositions have excellent properties and find utility as molding compositions and as compatibilizers for blends of similar polymers. Suitable epoxytriazine-capped polyphenylene ethers may be prepared by reaction of a polyphenylene ether with an epoxychlorotriazine such as diglycidyl chlorocyanurate, n-butyl glycidyl chlorocyanurate or mesityl glycidyl chlorocyanurate.

Abstract: A simplified method of forming polycrystalline translucent-to-transparent yttria-gadolinia scintillators comprises coprecipitating oxalates of the yttria-gadolinia composition, drying the oxalates at about 75.degree. C. to 125.degree. C., forming an aqueous suspension of the dried oxalates, and agitating the suspension while admixing an effective amount of an ammonium hydroxide solution to disperse agglomerations of the oxalate coprecipitates. The dispersed oxalates are calcined to substantially fully oxidize the oxalates and form an oxide powder of the yttria-gadolinia composition. The oxide powder is cold pressed to form a compact, and the compact is sintered in a reducing atmosphere or vacuum to form the polycrystalline translucent-to-transparent yttria-gadolinia scintillator.

Abstract: The molar concentration of chloroformate in an organic chloroformate solution is determined by adding an excess of a monohydroxyaromatic compound, water and a catalytic amount of a 4-dialkylaminopyridine such as 4-dimethylaminopyridine, titrating with aqueous base and taking as the end point the volume of base which achieves complete conversation of chloroformate groups to monoaromatic carbonate groups, as shown by a rapid rise in the pH of the aqueous phase of more than two points to a value in the range of 7-9. This method is particularly applicable to the determination of bischloroformate molar concentration in systems to be converted to cyclic polycarbonate oligomers. Conversion may be effected by condensation in the presence of a trialkylamine and aqueous base in the amount of about 3 moles per mole of bischloroformate.

Abstract: Blends of aromatic polycarbonate, alkylnaphthalene-formaldehyde condensation product and an impact modifier produce easy-flow, tough, stiff thermoplastics. The thermoplastics can be used to injection mold thin-walled housings for electronic circuits.

Abstract: A method for operating a computer to control the manufacture process of zirconium tubes in a pilger mill operation, the computer including an electronic memory and being coupled to the pilger mill to receive, as input, data related to the operation of the mill. The method comprising, in one embodiment, the steps of storing in the computer memory respective test signals, each test signal corresponding to a signal obtained by inspecting a tube manufactured by the mill with a respective, known defective operation condition, inspecting a zirconium tube finished by the manufacture process and generating a signal representative of the physical dimensions and material configuration of the tube, comparing the generated representative signal of the zirconium tube with the stored test signals, alerting an operator if the generated representative signal of the zirconium tube correlates to a stored test signal, and identifying the defective operation condition which corresponds to the correlated stored test signal.

Abstract: Polyarylene ether-polyalkenamer copolymers are provided by effecting a ring-opening metathesis polymerization (ROMP) of a cycloalkene such as, cyclooctene in the presence of a polyarylene ether having an ester link cycloalkenyl group. An effective amount of a metallic catalyst, such as an osmium or a ruthenium halide, can be used to catalyze the metathesis.

Abstract: Apparatus for heating a plastic sheet uses a high dielectric constant material (HDCM) to shape an RF electric field to be either concentrated or uniform as desired depending upon the object to be formed from the sheet. Electrodes can be annular with a circular or elliptical cross-section or be plates or wires, and can be disposed in the HDCM or exterior of the HDCM. A process for heating a plastic material comprises generating an RF field and shaping the field near the material using high dielectric constant members.

Abstract: A phase shift generator receives two input pulse signals and generates two output pulse train signals, each having a 50% duty cycle, which are phase-shifted in a range from 0.degree. to 180.degree. by an amount proportional to the duty cycle of the input pulse train signals and also proportional to the power supply load requirement.

Abstract: In a phased array acoustic transducer which has elements of different sizes, the piezoelectric material of large elements is subdiced to produce smaller segments to limit the overall piezoelectric segment size variation within the array to up to 55% or more without significant adverse effect on phased array processsing.

Abstract: A method for providing improved castability in a gamma titanium aluminide is taught. The method involves adding inclusions of boron to the titanium aluminide containing chromium and tantalum. Boron additions are made in concentrations between 0.5 to 2 atomic percent. Fine gain equiaxed microstructure is formed from solidified melt. Property improvements are also achieved.

Abstract: A metal composition is formed into a sheet by the method comprising; spray forming the metal composition to form a cylindrical deposit, and wire electric discharge machining the cylindrical deposit in a preselected spiral path parallel to the axis of the cylindrical deposit to form the sheet.

Abstract: A method for applying a protective coating to the inner surface of the arc tube of a high-intensity metal halide discharge lamp involves dosing the arc tube with an inert gas that is doped with a metal hydride gas. Preferably, the metal hydride gas comprises silane. The arc tube is heated to a sufficiently high temperature to decompose the silane gas. As a result, silicon is deposited as a protective coating on the inner surface of the arc tube wall. The hydrogen gas that is generated by the silane decomposition is removed from the system either by pumping it out before dosing the arc tube with the final arc tube fill, or by diffusion through the arc tube wall during operation of the lamp.

Abstract: A coating comprised of a continuous film of about 1 to 10 microns of condensed high energy atoms of chromium is found to remain adherent on titanium substrates during repeated thermal recycling while providing substantial oxidation protection up to about 909.degree. C. A film of a ductile chromium alloy that forms a continuous chromium oxide scale can be used instead of the chromium film. The film is deposited by physical vapor deposition processes depositing atoms having a high kinetic energy.

Abstract: A series resonant inverter is controlled to provide a substantially constant output voltage to a load. The control utilizes a combination of optimal control methods and phase modulation to enable time optimal responses to changes in state of the system. State determinants (including resonant capacitor voltage, resonant inductor current, source voltage, and output load voltage) are continuously monitored, and an optimal control signal is generated therefrom. When operating within the operable frequency range of the inverter's controllable switch means, frequency is varied to maintain proper operation. When operating at an extremity of the operable frequency range, phase modulation is employed.