Abstract: A foldable tail assembly for an aircraft includes a stabilizer and a pair of right and left fins mounted with respect to the stabilizer so that the fins may lay flat over the stabilizer during periods when the aircraft is not flight-ready, and so that the fins may be erected above the stabilizer to form a triangular configuration when the aircraft is ready to fly.

Abstract: When a disturbance (for example, lightning strike) occurs on a high-voltage overhead transmission line, the line must be checked for any possible damage. If the distance-to-fault is known, line crews can be quickly dispatched for any necessary repair. The present invention is a fault location method and system that uses filtered, time-synchronized positive- or negative-sequence voltage and current measurements from both ends of the overhead transmission line to determine the exact distance to the fault with respect to either end.

Abstract: Streetlight poles are lifted to a vertical position for installation in a mounting hole or on a support stand by connecting the lift cable of a boom to an elongate sling that is releasably attached to the pole.

Abstract: An automatic setup backscatter particulate monitor includes a small source (38) of narrow beam radiant energy directed into a gas stream containing particulates. A lens (34) that is mounted behind the radiant energy source (38) collects the energy reflected back from the particulates and concentrates it on a photodetector (48). The beam is directed into duct at an angle greater than twice the beam spread, minimizing reflection off opposing wall surfaces. Internal radiant energy sources are periodically directed to the detector to verify system integrity. Backscattered energy is corrected for energy reflected from the opposite stack wall and for ambient energy.

Abstract: Bulk, low impurity aluminum nitride (AlN) single crystals are grown by sublimation or similar deposition techniques at growth rates greater than 0.5 mm/hr.

Abstract: A vaginal device provides physical and chemical barriers to contraception or protection against sexually transmitted diseases, or both. The device includes a towelette having approximately 1 to 10 ml of preventive formulation incorporated therein by absorption. During intercourse, the towelette rests in the upper vagina and effectively functions as both a physical and chemical barrier to contraception. In some embodiments, the towelette may become compressed into a crumpled, disc-like shape, which may enhance its properties as a physical barrier. In other embodiments, the vaginal device includes a flexible ring that is affixed to the towelette to define a dome-shaped towelette portion on one side of the ring and a depending skirt on the other side, with the dome portion being designed to cover the cervix. Means to facilitate insertion and removal of the device are described.

Abstract: Normally closed valves that operate in the environment of nuclear power plants are provided with surface-modified valve seat components to alleviate sticking of the valves. The surface modification is achieved by ion implantation of a coating of, for example, platinum, palladium, platinum/palladium or palladium/gold on at least one valve seat component.

Abstract: A diagnostic device and associated operational procedure are used to both verify the integrity of components of high intensity discharge light fixtures and also troubleshoot problems in the wiring connecting the light fixture to the AC power source (transformer). The diagnostic device is a rugged, self-contained unit that can be connected across the ballast in the fixture for verifying component integrity, while also being adapted to load the AC power line that powers the fixture to detect problems in the wiring between the AC power source and the fixture.

Abstract: A solid state device protects large industrial electromagnets from the effects of dissipating stored magnetic energy when the supply voltage to the electromagnet is removed (for example, by accidental cutting of the power cables) while the electromagnet is energized. The device also serves as a safety device to protect operating personnel against serious injury or death when the personnel disconnect the electromagnet and power cables while the electromagnet is energized. The device monitors the voltage at the terminals of an electromagnet and, when the voltage exceeds a predetermined trigger voltage indicating an open magnet discharge path, causes the magnet energy to be safely dissipated in a power semiconductor circuit.

Abstract: Bulk, low impurity aluminum nitride:silicon carbide (AlN:SiC) alloy single crystals are grown by deposition of vapor species containing Al, Si, N and C on a crystal growth interface.

Abstract: An inadequate original equipment transmission in a right hand drive vehicle, for example a postal vehicle, is replaced with a more suitable transmission designed for a left hand drive vehicle. A right-to-left change-over linkage connects the shift rod emanating from the driver's gear selector lever to the shift lever on the left side of the replacement transmission. A kit containing necessary parts for replacing the transmission is disclosed. Also disclosed is a step-by-step operational procedure for carrying out the transmission replacement.

Abstract: Large diameter single crystals of aluminum nitride (AlN) are grown isotropically by injecting a nitrogen-containing gas into liquid aluminum at elevated temperatures. A seed crystal that is maintained at a temperature below that of the surrounding liquid aluminum is pulled from the melt, while the AlN that is formed in the melt is deposited on the seed crystal. An apparatus for carrying out the method is also disclosed.

Abstract: Low defect density, low impurity bulk single crystals of AlN, SiC and AlN:SiC alloy are produced by depositing appropriate vapor species of Al, Si, N, C on multiple nucleation sites that are preferentially cooled to a temperature less than the surrounding surfaces in the crystal growth enclosure. The vapor species may be provided by subliming solid source material, vaporizing liquid Al, Si or Al--Si or injecting source gases. The multiple nucleation sites may be unseeded or seeded with a seed crystal such as 4 H or 6 H SiC.

Abstract: Simulated diamond gemstones are produced by faceting and polishing bulk single crystals of colorless synthetic aluminum nitride or aluminum nitride:silicon carbide alloys.

Abstract: Bulk, low impurity aluminum nitride (AlN) single crystals are grown by sublimation or similar deposition techniques at growth rates greater than 0.1 mm/hr.

Abstract: Bulk, low impurity silicon carbide single crystals are grown by deposition of vapor species containing silicon and vapor species containing carbon on a crystal growth interface. The silicon source vapor is provided by vaporizing liquid silicon and transporting the silicon vapor to a crystal growth crucible. The carbon vapor species are provided by either a carbon containing source gas (for example, CN) or by flowing the silicon source vapor over or through a solid carbon source, for example flowing the silicon vapor through porous graphite or a bed of graphite particles.

Abstract: Bulk, low impurity aluminum nitride (AlN) single crystals are grown by sublimation or similar deposition techniques at growth rates greater than 0.5 mm/hr.

Abstract: Large diameter single crystals of aluminum nitride (AlN) are grown isotropically by injecting a nitrogen-containing gas into liquid aluminum at elevated temperatures. A seed crystal that is maintained at a temperature below that of the surrounding liquid aluminum is pulled from the melt, while the AlN that is formed in the melt is deposited on the seed crystal. An apparatus for carrying out the method is also disclosed.

Abstract: A target gemstone is irradiated with ultraviolet energy while sensing the electrical potential across the gemstone. A silicon carbide gemstone will generate an electrical potential and, therefore, can be positively identified, as distinct from other gemstones such as diamond and cubic zirconia that do not produce a potential.

Abstract: Synthetic gemstones are produced by growing single crystals of silicon carbide, fashioning the silicon carbide into gemstone cores, and thereafter depositing a thin coating of diamond on the core.