Abstract: Disclosed herein is a composite co-fiber comprising a plurality of ceramic tows; one or more sacrificial yarns; where the sacrificial yarns are operative to undergo dissolution, decomposition or melting upon being subjected to an elevated temperature; and wherein the sacrificial yarns leave open spaces in the co-fiber upon being subjected to decomposition, dissolution or melting.

Abstract: This invention is a manually tunable underwater breathing apparatus (UBA) which the resonant frequency of the UBA may be adjusted to meet the diver's breathing frequency by controlling the inertance component of the UBA impedance. The principles of the present invention may be adapted to existing UBA by adding a tuning apparatus comprising a valve, a tee and a tuned length of hose. Water displaced by volume change in the breathing bag due to exhalation/inhalation is partly diverted through the valve. Depending on the valve opening set by the diver the inertance and resonant frequency of the UBA can be altered to reduce breathing load.

Abstract: This invention comprises a tunable underwater breathing apparatus (UBA) in hich the resonant frequency of the UBA may be adjusted to meet the diver's breathing frequency by controlling the inertance component of the UBA impedance. The principles of the present invention may be adapted to existing UBA with minor redesign and some additions.

Abstract: A load lock removes particulate contamination during microelectronic manufacturing. The load lock may have a single door or two doors, or a single door and a funnel valve. A passageway is defined through the load lock when the door or doors, or the funnel valve, are opened. The particulate contamination is removed from the load lock by providing a laminar flow of gas through the passageway. The source for generating the laminar flow may be external to the load lock or internal to the load lock.

Abstract: A method for forming on a substrate a relatively thick, densified, essentially non-porous, fine-grained layer of a non-conductive material. The method comprises the steps of vapor depositing onto such substrate a starting material while simultaneously bombarding the substrate with ions of a preselected gas. During the process, the substrate is disposed in the atmosphere of a preselected gas, and an RF field is established between the substrate and an opposing electrode structure to produce a plasma of such gas in the vicinity of the substrate. The substrate is electrically biased to attract ions from the plasma, such ions serving to impact on the substrate and thereby densify the vapor deposit thereon. Preferably, the starting material is one which reacts with the gas ions to form the desired material on the substrate; alternatively, the starting material comprises the desired material, in which case the gas plasma preferably comprises an inert gas.