Abstract: Thermocouples of the present invention provide stability and performance reliability in systems involving high temperatures and vacuums by employing a bimetallic thermocouple sensor wherein each metal of the sensor is selected from a group of metals comprising tantalum and rhenium and alloys containing only those two metals. The tantalum, rhenium thermocouple sensor alloys provide bare metal thermocouple sensors having advantageous vapor pressure compatibilities and performance characteristics. The compatibility and physical characteristics of the thermocouple sensor alloys of the present invention result in improved emf, temperature properties and thermocouple hot junction performance. The thermocouples formed of the tantalum, rhenium alloys exhibit reliability and performance stability in systems involving high temperatures and vacuums and are adaptable to space propulsion and power systems and nuclear environments.

Abstract: A spatial filtered Q-switched laser system is disclosed having means to prevent ionization of air in close proximity to the aperture of the spatial filter. A compound lens system having an astigmatic focus is disposed between the laser and the spatial filter for defocusing the light beam emanating from the laser in the vicinity of the aperture of the spatial filter to an intensity below that which produces ionization of air. The preferred construction of the compound lens system as viewed from the laser comprises a cylindrical lens and a pair of positive lenses.

Abstract: A solar cell shingle may be made of an array of solar cells on a lower portion of a substantially rectangular shingle substrate made of fiberglass cloth or the like. The solar cells may be encapsulated in flourinated ethylene propylene (FEP) or some other weatherproof translucent or transparent encapsulant to form a combined electrical module and a roof shingle. The interconnected solar cells are connected to connectors at the edge of the substrate through a connection to a common electrical bus or busses. An overlap area is arranged to receive the overlap of a cooperating similar shingle so that the cell portion of the cooperating shingle may overlie the overlap area of the roof shingle. Accordingly the same shingle serves the double function of an ordinary roof shingle which may be applied in the usual way and an array of cooperating solar cells from which electrical energy may be collected.

Abstract: A hydrostatic bearing support system is provided which comprises a bearing housing having a polygonally configured outer surface which defines at least three symmetrically disposed working faces and a plurality of pressure plates, each of which is disposed relatively opposite a corresponding working face and spaced therefrom to define a gap therebetween. A hydrostatic support film is created in the gap for supporting the housing in spaced relationship to the pressure plates.

Abstract: The formation of voids through interdiffusion in bimetallic welded structures exposed to high operating temperatures is inhibited by utilizing an alloy of the parent materials in the junction of the parent materials or by preannealing the junction at an ultrahigh temperature. These methods are also used to reduce the concentration gradient of a hardening agent.

Abstract: Circuitry for maintaining an arc or spark across a spark gap for a desired length of time is disclosed. A high-voltage, direct-current (dc) source is connected in series with a secondary winding of a high voltage, step-up transformer or coil and a spark gap such as a spark plug for example. The high-voltage source may be on continuously or may be turned on and off by a control circuit such as a solid state switch which is, in turn, responsive to a timing device such as a set of ignition contact points or a magnetic pulse generator operating in synchronism with a spark ignition engine. The timing device also provides signals to a current switching circuit which interrupts current flow through a primary winding of the high-voltage coil at the prescribed time that a spark is desired at the spark gap.The control circuit may, if desired, include both a switch and a multivibrator if the timer is of the pulse-generating magnetic type.

Abstract: A corneal seal device is provided which, when placed in an incision in the eye, permits the insertion of a surgical tool or instrument through the device into the eye.The device includes a seal chamber which opens into a tube which is adapted to be sutured to the eye and serves as an entry passage for a tool. A sealable aperture in the chamber permits passage of the tool through the chamber into the tube and hence into the eye. The chamber includes inlet ports adapted to be connected to a regulated source of irrigation fluid which provides a safe intraocular pressure.

Abstract: A retaining assembly is provided for locking radially extending blades in a rotor disc associated with a gas turbine engine. The assembly includes a pair of spaced apart lugs axially extending from one side of the disc to form an access gap for insertion of a blade tang into a dovetail slot in the rotor disc. A pair of axially aligned inwardly facing recesses are disposed in the lugs. A retaining member resides in the recesses and extends across the gap to preclude egress of the blade tang from the dovetail slot. The retaining member includes at least one axially extending protrusion adapted to radially overlap and abuttingly engage a radially inwardly facing abutment surface on the lugs.

Abstract: The invention relates to laminate structures and specifically to essentially anisotropic fiber composite laminates wherein metal foils are selectively disposed within the laminate to produce increased resistance to high velocity impact, fracture, surface erosion, and other stresses within the laminate.

Abstract: In a process or method according to the invention the parts of an electrical contact device, such as a slip ring comprising the ring to receive the liquid metal and the probe or brush for contacting the liquid metal are treated by sputter etching to remove the parent metal oxide. Prior to exposure of the electrodes to any oxygen, a sacrificial metal is sputter deposited on the parts. Preferably this sacrificial metal is one that oxidizes slowly and is readily dissolved by the liquid metal. The sacrificial metal may then be removed from unwanted areas. The remainder of the ring and the probe to be wet by the liquid metal are submerged in the liquid metal or the liquid metal is flushed over these areas, preferably while they are being slightly abraded, until all the sacrificial material on these portions is wet by the liquid metal. In doing so the liquid metal dissolves the sacrificial metal and permanently wets the parent metal.

Abstract: Gels are formed from silica powders and hydrochloric acid. The gels can then be impregnated into a polymeric foam and the resultant sheet material can then be used in applications where the transport of chloride ions is desired. Specifically disclosed is the utilization of the sheet in electrically rechargable redox flow cells which find application in bulk power storage systems.

Abstract: An improved material for use in a catalytic reactor which reduces nitrogen oxide from internal combustion engines is in the form of a zirconium-modified, precipitation-strengthened nickel-copper alloy. This material has a nominal composition of Ni-30 Cu-0.2 Zr and is characterized by improved high temperature mechanical properties.

Abstract: The invention is directed to a screen anode for an ion thruster. The anode is constructed of a woven mesh screen, preferably of a stainless steel wire cloth with a mesh size less than the intergrid gap or openings of the screen grid or accelerator grid systems of the ion thruster. The screen anode is sputter coated with tantalum as a result of thruster operation. Because of the fineness of the screen anode any spalled material from the tantalum coated anode is in such small dimensions that the spalled pieces cannot interfere with the accelerator and screen grid systems and with the focusing therebetween.

Abstract: Advantage is taken of the current-exponential voltage characteristic of a diode over a certain range whereby the incremental impedance across the diode is inversely proportional to the current through the diode. Accordingly, a divider circuit employs a bias current through the diode proportional to the desired denominator and applies an incremental current to the diode proportional to the numerator. As a result, the incremental voltage across the diode is proportional to the quotient.

Abstract: A non-oxide anti-reflective coating is used with a transparent plastic cover of fluorinated ethylene propylene copolymer on a silicon solar cell to increase the resistance to damage caused by electron bombardment.

Abstract: There is disclosed a bulk energy storage system including an electrically rechargeable reduction-oxidation (REDOX) cell divided into two compartments by a membrane, each compartment containing an electrode. An anode fluid is directed through the first compartment at the same time that a cathode fluid is directed through the second compartment, thereby causing the electrode in the first compartment to have a negative potential while the electrode in the second compartment has a positive potential. The electrodes are inert with respect to the anode and cathode fluids used and the membrane is substantially impermeable to all except select ions of both the anode and cathode fluid, whether the cell is fully charged or in a state of discharge.Means are provided for circulating the anode and cathode fluids and the electrodes are connected to an intermittent or non-continuous electrical source, which when operating, supplies current to a load as well as to the cell to recharge it.

Abstract: An ion thruster beam shield is provided that comprises a cylindrical housing that extends downstream from the ion thruster and a plurality of annular vanes which are spaced along the length of the housing, and extend inwardly from the interior wall of the housing. The shield intercepts and stops all charge exchange and beam ions, neutral propellant, and sputter products formed due to the interaction of beam and shield emanating from the ion thruster outside of a fixed conical angle from the thruster axis. Further, the shield prevents the sputter products formed during the operation of the engine from escaping the interior volume of the shield.

Abstract: A gas-lubricated thrust bearing employs relatively rigid inwardly cantilevered spokes carrying a relatively resilient annular member or annulus. This annulus acts as a beam on which are mounted bearing pads. The resilience of the beam mount causes the pads to accept the load and, with proper design, responds to a rotating thrust-transmitting collar by creating a gas film between the pads and the thrust collar. The bearing may be arranged for load equalization thereby avoiding the necessity of gimbal mounts or the like for the bearing. It may also be arranged to respond to rotation in one or both directions.

Abstract: Bombarding a cesium heat pipe with high energy particles causes a spallation reaction which produces vapors of .sup.123 Xe and contaminants. The contaminants are removed in a dry ice cold trap while the .sup.123 Xe condenses in a liquid nitrogen trap where it decays to .sup.123.sub.I.

Abstract: Bombarding a cesium heat pipe with high energy particles causes a spallation reaction which produces vapors of .sup.123 Xe and contaminants. The contaminants are removed in a dry ice cold trap while the .sup.123 Xe condenses in a liquid nitrogen trap where it decays to .sup.123 I.