Abstract: The process for the synthesis of rhenium powders comprises the injection of ammonium perrhenate powder through a carrier gas in a plasma torch of a plasma reactor operated using a mixture including hydrogen as the plasma gas, yielding metallic rhenium under the following chemical reaction: 2NH4ReO4+4H2?2Re+N2?+8H2O?. The reactor is provided with a quench zone for cooling the metallic rhenium so as to yield rhenium nano and micro powders.

Abstract: The invention concerns a process for the spheroidisation, densification and purification of powders through the combined action of plasma processing, and ultra-sound treatment of the plasma-processed powder. The ultra-sound treatment allows for the separation of the nanosized condensed powder, referred to as ‘soot’, from the plasma melted and partially vaporized powder. The process can also be used for the synthesis of nanopowders through the partial vaporization of the feed material, followed by the rapid condensation of the formed vapour cloud giving rise to the formation of a fine aerosol of nanopowder. In the latter case, the ultra-sound treatment step serves for the separation of the formed nanopowder form the partially vaporized feed material.

Abstract: A process and apparatus for the synthesis of metal oxide nanopowder from a metal compound vapour is presented. In particular a process and apparatus for the synthesis of TiO2 nanopowder from TiCl4 is disclosed. The metal compound vapour is reacted with an oxidizing gas in electrically induced RF frequency plasma thus forming a metal oxide vapour. The metal oxide vapour is rapidly cooled using a highly turbulent gas quench zone which quickly halts the particle growth process, yielding a substantial reduction in the size of metal oxide particles formed compared with known processes. The metal compound vapour can also react with a doping agent to create a doped metal oxide nanopowder. Additionally, a process and apparatus for the inline synthesis of a coated metal oxide is disclosed wherein the metal oxide particles are coated with a surface agent after being cooled in a highly turbulent gas quench zone.

Abstract: The process for the synthesis of rhenium powders comprises the injection of ammonium perrhenate powder through a carrier gas in a plasma torch of a plasma reactor operated using a mixture including hydrogen as the plasma gas, yielding metallic rhenium under the following chemical reaction: 2 NH4ReO4+4 H2?2 Re+N2?+8 H2O?. The reactor is provided with a quench zone for cooling the metallic rhenium so as to yield rhenium nano and micro powders.

Abstract: A process for the in-flight surface treatment of powders using a Dielectric Barrier Discharge Torch operating at atmospheric pressures or soft vacuum conditions is described herein. The process comprising feeding a powder material into the Dielectric Barrier Discharge Torch yielding powder particles exhibiting a reduced powder agglomeration feature; in-flight modifying the surface properties of the particles; and collecting coated powder particles. An apparatus for surface treating micro- and nanoparticles comprising a Dielectric Barrier Discharge Torch operating at atmospheric pressure or soft vacuum conditions is also described herein.

Abstract: A process for synthesizing metal nanopowders by introducing metal carbonyl into an induction plasma torch. By taking advantage of the much lower dissolution temperature of carbonyl as opposed to the high melting temperature of conventional metal powder feeds less torch power is required. Moreover, in contrast to current powder production techniques utilizing electrode based plasma torches, the induction plasma torch does not introduce contaminants into the nanopowder.

Abstract: A process and apparatus for preparing a nanopowder are presented. The process comprises feeding a reactant material into a plasma reactor in which is generated a plasma flow having a temperature sufficiently high to vaporize the material; transporting the vapour by means of the plasma flow into a quenching zone; injecting a preheated quench gas into the plasma flow in the quenching zone to form a renewable gaseous condensation front; and forming a nanopowder at the interface between the renewable controlled temperature gaseous condensation front and the plasma flow.

Abstract: The invention concerns a process for the spheroidisation, densification and purification of powders through the combined action of plasma processing, and ultra-sound treatment of the plasma-processed powder. The ultra-sound treatment allows for the separation of the nanosized condensed powder, referred to as ‘soot’, from the plasma melted and partially vaporized powder. The process can also be used for the synthesis of nanopowders through the partial vaporization of the feed material, followed by the rapid condensation of the formed vapour cloud giving rise to the formation of a fine aerosol of nanopowder. In the latter case, the ultra-sound treatment step serves for the separation of the formed nanopowder form the partially vaporized feed material.

Abstract: A process and apparatus for synthesizing a nanopowder is presented. In particular, a process for the synthesis of nanopowders of various materials such as metals, alloys, ceramics and composites by induction plasma technology, using organometallic compounds, chlorides, bromides, fluorides, iodides, nitrites, nitrates, oxalates and carbonates as precursors is disclosed. The process comprises feeding a reactant material into a plasma torch in which is generated a plasma flow having a temperature sufficiently high to yield a superheated vapour of the material; transporting said vapour by means of the plasma flow into a quenching zone; injecting a cold quench gas into the plasma flow in the quenching zone to form a renewable gaseous cold front; and forming a nanopowder at the interface between the renewable gaseous cold front and the plasma flow.

Abstract: A process for the manufacture of sputtering target comprises the steps of i) providing a substrate; ii) plasma melting of a material selected to form the sputtering target, yielding droplets of molten material; and iii) deposition of the droplets onto the substrate, yielding a sputtering target comprised of the coated layer of the material on the substrate. In some application, it might be preferable that the substrate be a temporary substrate and iv) to join the coated temporary target via its coated layer to a permanent target backing material; and v) to remove the temporary substrate, yielding a sputtering target comprised of the coated layer of the material on the permanent target backing material. The plasma deposition step is carried out at atmospheric pressure or under soft vacuum conditions using, for example, d.c. plasma spraying, d.c. transferred arc deposition or induction plasma spraying. The process is simple and does not require subsequent operation on the resulting target.

Abstract: A process and apparatus for the synthesis of metal oxide nanopowder from a metal compound vapour is presented. In particular a process and apparatus for the synthesis of TiO2 nanopowder from TiCl4 is disclosed. The metal compound vapour is reacted with an oxidizing gas in electrically induced RF frequency plasma thus forming a metal oxide vapour. The metal oxide vapour is rapidly cooled using a highly turbulent gas quench zone which quickly halts the particle growth process, yielding a substantial reduction in the size of metal oxide particles formed compared with known processes. The metal compound vapour can also react with a doping agent to create a doped metal oxide nanopowder. Additionally, a process and apparatus for the inline synthesis of a coated metal oxide is disclosed wherein the metal oxide particles are coated with a surface agent after being cooled in a highly turbulent gas quench zone.

Abstract: The process for the synthesis of rhenium powders comprises the injection of ammonium perrhenate powder through a carrier gas in a plasma torch of a plasma reactor operated using a mixture including hydrogen as the plasma gas, yielding metallic rhenium under the following chemical reaction: 2 NH4ReO4+4 H2?2 Re+N2?+8 H2O?. The reactor is provided with a quench zone for cooling the metallic rhenium so as to yield rhenium nano and micro powders.

Abstract: An induction plasma torch comprises a tubular torch body, a gas distributor head located at the proximal end of the torch body for supplying at least one gaseous substance into the chamber within the torch body, a higher frequency power supply connected to a first induction coil mounted coaxial to the tubular torch body, a lower frequency solid state power supply connected to a plurality of second induction coils mounted coaxial to the tubular torch body between the first induction coil and the distal end of this torch body. The first induction coil provides the inductive energy necessary to ignite the gaseous substance to form a plasma. The second induction coils provide the working energy necessary to operate the plasma torch. The second induction coils can be connected to the solid state power supply in series and/or in parallel to match the impedance of this solid state power supply.

Abstract: A process and apparatus for the synthesis of metal oxide nanopowder from a metal compound vapour is presented. In particular a process and apparatus for the synthesis of TiO2 nanopowder from TiCl4 is disclosed. The metal compound vapour is reacted with an oxidizing gas in electrically induced RF frequency plasma thus forming a metal oxide vapour. The metal oxide vapour is rapidly cooled using a highly turbulent gas quench zone which quickly halts the particle growth process, yielding a substantial reduction in the size of metal oxide particles formed compared with known processes. The metal compound vapour can also react with a doping agent to create a doped metal oxide nanopowder. Additionally, a process and apparatus for the inline synthesis of a coated metal oxide is disclosed wherein the metal oxide particles are coated with a surface agent after being cooled in a highly turbulent gas quench zone.

Abstract: A process and apparatus for the synthesis of metal oxide nanopowder from a metal compound vapour is presented. In particular a process and apparatus for the synthesis of TiO2 nanopowder from TiCl4 is disclosed. The metal compound vapour is reacted with an oxidizing gas in an electrically induced RF frequency plasma thus forming a metal oxide vapour. The metal oxide vapour is rapidly cooled using a highly turbulent gas quench zone which quickly halts the particle growth process, yielding a substantial reduction in the size of metal oxide particles formed. The metal compound vapour can also be reacted with a doping agent to create a doped metal oxide nanopowder. Additionally, a process and apparatus for the inline synthesis of a coated metal oxide is disclosed wherein the metal oxide particles are coated with a surface agent after being cooled in a highly turbulent gas quench zone.

Abstract: An in-wall speaker has a variably tuned vibration absorber to absorb and dissipate vibrations in the speaker and surroundings that tend to cause distortions. The vibration absorbing device, including a stack of viscoelastic damping plates, is secured to the speaker or connected structure via a trapezoidally shaped tuning plate, which provides a varying degree of cantilever in different portions of the stack of plates. The effect is to absorb vibrations over a broad range of frequencies.

Abstract: A glass-to-metal hermetic seal device which is adapted for suppressing or dissipating electrostatic energy comprises an improved glass-to-metal hermetic seal, with the interior of the device incorporating and creating a gas-filled electrical discharge tube. The gas is an ionizable gas and may conveniently comprise a mixture of nitrogen and Argon. The devices of the present invention utilize one or more electrodes which enter the gas-filled chamber, and when the electrical field of sufficiently high potential is created within the gas-filled chamber, the gas ionizes and becomes conductive so as to effectively dissipate the field.

Abstract: A glass-to-metal hermetic seal device which is particularly adapted for application in high pressure and other hostile environments for suppressing or dissipating electrostatic energy incorporating an improved glass-to-metal hermetic seal. The interior of the device incorporates and creates an in-situ gas-filled electrical discharge tube. The gas is an ionizable gas and may conveniently comprise a mixture of nitrogen and Argon, although other ionizable gases such as Xenon may be used. The devices of the present invention utilize one or more electrodes which enter the gas-filled chamber, and when the electrical field of sufficiently high potential is created within the gas-filled chamber, the gas ionizes and becomes conductive so as to effectively dissipate the field.

Abstract: A vibration absorbing device for a speaker enclosure is tuned upon installation to the speaker enclosure to achieve maximum attenuation of vibrations in a selected frequency range. The vibration absorber, which includes a series of vibration damping plates separated by spacers, is positioned at varying degrees of overhang on a mounting plate on a panel of the enclosure until attenuation of the desired frequency band is maximized. Then the absorber is secured to the speaker enclosure with an appropriately sized permanent mounting plate.

Abstract: A vibration attenuating device for loudspeaker enclosures and other mechanical vibrating bodies includes one or more damping plates of viscoelastic material positioned to receive vibration energy transferred from the vibrating body. The vibration energy is transferred away from the speaker enclosure or other body and is dissipated as heat due to the internal molecular structure of the viscoelastic material, suppressing noise normally produced by the vibrating body. In various different embodiments, the vibration damping device includes damping plates shaped or mounted in such a way as to provide for attenuation of a wide band of frequencies of vibration. The damping plates themselves may each have a configuration providing for continuously varying frequency response along the length or circumference of the plate, and there may be included a plurality of different-sized plates, each responding essentially to a different frequency band.