Abstract: Described herein are batches of nanoscale phosphor particles having an average particle size of less than about 200 nm and an average internal quantum efficiency of at least 40%. The batches of nanoscale phosphor particles can be substantially free of impurities. Also described herein are methods of manufacturing the nanoscale phosphor particles by passing phosphor particles through a reactive field to thereby dissociate them into elements and then synthesizing nanoscale phosphor particles by nucleating the elements and quenching the resulting particles.

Abstract: Methods of generating nanoparticles are described that comprises feeding nebulized droplets into a radio frequency plasma torch to generate nanoparticles, wherein the majority of the nanoparticles generated have a diameter of less than about 50 nm. These methods are useful for synthesizing nanoparticles of metals, semiconductors, ceramics or any other material class where the precursors are either in liquid form or can be dissolved or suspended in a suitable liquid. Methods of feeding nebulized droplets and central gas into a radio frequency plasma torch and apparatus for generating nanoparticles are also described.

Abstract: Described herein are batches of nanoscale phosphor particles having an average particle size of less than about 200 nm and an average internal quantum efficiency of at least 40%. The batches of nanoscale phosphor particles can be substantially free of impurities. Also described herein are methods of manufacturing the nanoscale phosphor particles by passing phosphor particles through a reactive field to thereby dissociate them into elements and then synthesizing nanoscale phosphor particles by nucleating the elements and quenching the resulting particles.

Abstract: Methods of generating nanoparticles are described that comprises feeding nebulized droplets into a radio frequency plasma torch to generate nanoparticles, wherein the majority of the nanoparticles generated have a diameter of less than about 50 nm. These methods are useful for synthesizing nanoparticles of metals, semiconductors, ceramics or any other material class where the precursors are either in liquid form or can be dissolved or suspended in a suitable liquid. Methods of feeding nebulized droplets and central gas into a radio frequency plasma torch and apparatus for generating nanoparticles are also described.

Abstract: Material droplet generator systems utilizing single-wire arc spray apparatus and methods are provided. In some embodiments, the apparatus include a single consumable, first wire electrode fed through a gas nozzle and a non-consumable, second electrode outside of and proximate a nozzle exit. In some embodiments, the second electrode may have at least a terminal or end portion having an axis that is oriented substantially perpendicular to an axis of the gas nozzle. The first wire electrode may form an angle of 5 degrees or less with the axis of the gas nozzle. Preferably, the first wire electrode forms an anode while the second electrode forms a cathode. In operation, the apparatus and methods produce a narrow beam thermal spray, which, when deposited upon a substrate surface, results in a high definition spray pattern and coating having distinct boundaries and a controllable thickness.

Abstract: Material droplet generator systems utilizing single-wire arc spray apparatus and methods are provided. In some embodiments, the apparatus include a single consumable, first wire electrode fed through a gas nozzle and a non-consumable, second electrode outside of and proximate a nozzle exit. In some embodiments, the second electrode may have at least a terminal or end portion having an axis that is oriented substantially perpendicular to an axis of the gas nozzle. The first wire electrode may form an angle of 5 degrees or less with the axis of the gas nozzle. Preferably, the first wire electrode forms an anode while the second electrode forms a cathode. In operation, apparatus and methods of the present invention produce a narrow beam thermal spray, which, when deposited upon a substrate surface, results in a high definition spray pattern and coating having distinct boundaries and a controllable thickness.

Abstract: A method and apparatus for the controlled synthesis and assembly of nanoparticles into nanostructured materials, including nanocomposites, includes a source of nanoparticles and a hypersonic impaction apparatus. The nanoparticles are impacted on a substrate through hypersonic impaction to thereby provide nanostructured materials as well as nanophase materials.

Abstract: A method is provided for preparing a diamond coating on a substrate. The method includes a first step of applying a partial diamond coating having an effective amount of void area therein to the work surface of a substrate. In a follow-up step the void area in the partial coating is filled with binder, preferably metallic binder. In a later step, diamond projecting outwardly from the binder is further grown, to generate a covering portion or a head portion extending over, and in protective relationship with, the binder or binder material. According to the present invention preferred products are also provided.

Abstract: A high current density component of a dynamoelectric machine rotor is cooled by the use of thermosyphons that carry heat from the heat generating element to a cooler part of the rotor. A homopolar generator is shown with a rotor having a core covered by a copper shell that when so cooled by thermosyphons can be operated with substantially longer pulse intervals than previously.

Abstract: A DC electric arc furnace utilizing a magnetic field stabilized electric arc. A DC magnetic field is employed to cause rotation and angular deflection of the electric arc about the surface of the melt. In one embodiment the DC magnetic field is induced by a field coil. In an alternate embodiment a specially shaped electrical insulating member can be positioned in the melt so that the flow of arc current through the melt creates a magnetic field which is used to cause arc rotation. In a further embodiment a plurality of coil sets are located about the periphery of the furnace are used in conjunction with current reversing and current sequencing means to create a rotating DC magnetic field which is used to rotate the arc. A ceramic electric insulator can also be supplied in the chamber of the furnace to prevent arc fixation in the region wherein the DC magnetic field is substantially parallel to the flow of arc current.

Abstract: A method for producing a metal by reduction of a metal halide characterized by the steps of feeding into a plasma such as the arc heated stream of an arc heater, a quantity of a reducing metal such as an alkali or alkaline earth metal, feeding into the plasma a quantity of a metal halide, maintaining the temperature of the reaction chamber wall higher than the vapor point of the alkali metal chloride formed or alkaline earth metal chloride formed but lower than the melting point of the elemental metal, co-products formed being an elemental metal and a gaseous salt, projecting the co-products into the reaction chamber to cause the metal to deposit on the interior wall of the collection chamber, removing the gaseous salt, heating the metal deposited on the interior of the reaction chamber with the arc heated stream thereby causing the elemental metal to fall gravitationally or be blown into an associated receptacle in the form of solidified globules and/or crystals and/or granules and/or large diameter powders.

Abstract: The invention provides a technique for interrupting current employing a plurality of series connected vacuum arcs in parallel with a resonating circuit. At least one of the series vacuum arcs is subjected to an oscillating transverse magnetic field which produces modulations in the arc voltage. The arc voltage modulations initiate oscillations in the parallel resonating circuit, producing current modulations in the series connected vacuum arcs. The current modulations rapidly extinguish the arcs, interrupting the current. Use of a plurality of series connected vacuum arcs improves the recovery voltage hold-off potential of the circuit.

Abstract: An electrical circuit breaking device adapted for connection in circuit with an electrical conductor for interrupting the current passing through the latter is disclosed herein. This device includes an arrangement of larger and smaller electrode contacting surfaces which are separated from one another in a way which improves the continuous current carrying capability of the device while maintaining satisfactory interruption capability.

Abstract: A vacuum arc current interruption device is installed in a current limiting circuit which includes a parallel resonant circuit. Means are provided for producing transverse lines of magnetic force in the arc gap between the electrodes in the vacuum enclosure. The energizing circuit for the magnetic field coils includes a capacitor bank employing unpolarized capacitors and a switch. After the capacitor bank is charged up, the switch is closed, discharging the capacitors through the field coils and producing lines of magnetic force in the arc gap. The field coils and capacitor bank together form a resonant field circuit having a characteristic resonant frequency which causes periodic reversals in the polarity of the lines of magnetic force. The oscillating magnetic field produces responsive oscillations in the arc voltage of an arc present in the arc gap of the vacuum device, which in turn causes oscillations of the arc current.

Abstract: A vacuum arc current switching device employs a shielding arrangement including a plurality of coaxially disposed cylindrical non-conducting members for minimizing exposure of the interior wall surfaces of the enclosure to vapor deposition of cathode material so as to prevent the formation of secondary arc terminals on the interior surfaces of the enclosure. The shielding being non-conducting prevents secondary arc formation which would otherwise permit arcing from the cathode to the shield and then back to the anode. The shielding further comprises annular transverse members disposed at the ends of the enclosure so as to protect the end wall surfaces as well.