Abstract: 1,3-Diazido-2-nitrazapropane, is disclosed as an energetic plasticizer, together with a method for producing same.

Abstract: A method of removing and preferably recovering sulfur values from an alkali metal sulfide and carbonate mixture comprising the steps of (1) introducing the mixture in an aqueous medium into a first carbonation zone and reacting the mixture with a gas containing a major amount of CO.sub.2 and a minor amount of H.sub.2 S; (2) introducing the resultant product from step 1 into a stripping zone maintained at subatmospheric pressure, and contacting this product with steam to produce a gaseous mixture, comprising H.sub.2 S and water vapor, and a liquor of reduced sulfide content; (3) introducing the liquor of reduced sulfide content into a second carbonation zone, and reacting the liquor with substantially pure gaseous CO.sub.2 in an amount sufficient to precipitate bicarbonate crystals and produce an offgas containing CO.sub.2 and H.sub.

Abstract: In a helicopter a servo system connected to operate in parallel with the rotor blade pitch controlling linkages and also to receive autopilot generated signals directing maneuvers. The system limits the autopilot control over the blade pitch or position in the short term and permits full control over the long term.

Abstract: Stress in a material is measured using electromagnetically generated, transverse elastic waves. A correlation is known to exist between the difference in velocity of orthogonally polarized transverse waves in the type material being measured and stress in the material. An electromagnetic transducer is used to generate orthogonally polarized waves traveling through the part at different velocities as a result of anisotropic stress in the part. The difference in velocity between the polarized waves is measured and compared to the correlation to obtain the stress existing in the part.

Abstract: A nuclear reactor having an inherently safe automatic shutdown capability comprising a pressure vessel, a core located within the vessel and containing a sufficient amount of fissionable material to establish and sustain a chain-type fission reaction, and a plurality of elongated conduits disposed in a regular arrangement within the vessel. Each of the conduits defines a fluid flow path and comprises a first section located within and extending through the core, and a second section located exteriorly of the core and positioned above the first section. Each of the conduits contains a plurality of substantially spherical bodies in a sufficient quantity to substantially fill the first section of each of the conduits. The conduits are provided with a first fluid connection to a lower part of the first section and a second fluid connection to an upper part of the second section for the passage of a pressurized fluid therethrough while maintaining the reactor in operation.

Abstract: An improved lithium electrode structure comprises an alloy of lithium, silicon, and boron in specified proportions and a supporting current-collecting matrix in intimate contact with said alloy. The lithium electrode of the present invention is utilized as the negative electrode in a rechargeable electrochemical cell.

Abstract: A communication system is illustrated wherein the communication links include automatically reversible amplifiers with the termination means of two links closing a loop. Upon failure of detection of a carrier signal in one of the links at the terminating end due to a break in that link, switches are automatically actuated to connect the momentarily unconnected portion of the broken link to the link that is still intact such that communication is restored in a new link configuration thereby accomplishing "fail-safe" operation without undue redundancy.

Abstract: A preamp for coupling to an avalanche photodiode (APD) of an optical receiver has an input stage including a dual gate field effect transistor (FET) and a single gate FET coupled in a cascade arrangement. The dual gate FET has its first gate coupled to the output of the APD, its second gate and source grounded, and its drain driving the gate of the single gate FET in a cascade arrangement. The source of the single gate FET is level-shifted and coupled by means of a feedback resistor to the first gate of the dual gate FET to provide a negative feedback. The output stage is a third FET with its gate coupled through a blocking capacitor to the source of the single gate FET in the input stage and with its drain providing the output of the preamp. In a preferred embodiment, the FETs used are GaAs FETs (GAASFETs).

Abstract: A method of making a junction in semiconductive materials to improve the spectral response of the junction in photovoltaic detectors. A first layer of semiconductive material is grown, by epitaxy technique, on a substrate of semiconductive material of the same conductivity type. Growth of the first layer is discontinued and the temperature is changed. Then a second layer of opposite conductivity type is grown on the first layer.

Abstract: Apparatus for testing the operability of a signal translation means which passes signal information containing a definable and repeatable characteristic such as a synchronization signal through the use of a spare similar device and a demodulating device which provides outputs upon detecting the signal passed by each signal translating device. As illustrated, regular and spare transmit multiplexing devices are used and logic information obtained from a spare receiver is used to indicate a failed condition.

Abstract: A system for developing a warning condition output signal when a monitored input variable exceeds a warn profile defined value defined as a predetermined function of an input reference variable, in which the warning condition output signal is delayed by a time .tau. from the time that a warning condition is sensed. The profile offset thus induced is compensated for by generating an anticipated future value of the reference variable after a time .tau. from the instant value and rate of change thereof, with the anticipated future value being utilized to generate the warn profile. Lag introduced by filtering which might be employed in generating the anticipated value, as well as any lag time existing between a reference variable failure and a failure condition signal which may be used to inhibit development of a warning condition signal, are then permissible, and are compensated for without profile offset by choosing a delay time .tau.

Abstract: An improved lithium electrode structure comprises an alloy of lithium, silicon, and iron in specified proportions and a supporting current-collecting matrix in intimate contact with said alloy. The lithium electrode of the present invention is utilized as the negative electrode in a rechargeable electrochemical cell.

Abstract: A method of interconnecting microelectronic components with flexible metallic interconnects. A layer of photoresist is applied to the surface of a microelectronic component and then removed from selected locations. A deposit of metal is applied to the selected location. A second layer of photoresist is applied over the first layer and over the deposited metal. The second layer of photoresist is removed from above the metal deposit and a second metal deposit is applied over the first metal deposit. These steps are repeated until a predetermined height of deposited metal is reached supported by layers of photoresist. The upper surface of the deposit and photoresist is polished flat and pads of metal deposited. A second microelectronic component having mating metal pads is positioned over the first microelectronic component and bonded to it through the mating metal pads. Finally, the layers of photoresist are removed.

Abstract: A passive replicator comprising a plurality of elongated bars interposed between an input propagation path and a plurality of output propagation paths.

Abstract: This invention relates to a communication system wherein a plurality of stations can communicate with each other, without going through a central switchboard; and more particularly to such a communication system that is as private as possible -- the commmunication system having, in addition, the capability of conference calls and a command-override.

Abstract: Method and apparatus for limiting the authority of a position servo system over an aircraft control surface. The amplitude of the energizing signal delivered to the actuator portion of the servo system is limited in accordance with a non-constant function of time.

Abstract: At least one of several transducers on a piezoelectric substrate is externally short-circuited by a series resonance circuit for suppression of triple transit echoes. The resonance circuit is additionally connected to an amplifier via a high input or output impedance. In multi-transducer systems any two transducers are prevented from communicating via echo signals by such resonance circuits. In filter cascades several resonance circuits may be included in the interstage coupling circuit or between the input and output amplifiers on the one hand and the cascade on the other hand.

Abstract: There is described an improved switching device for use in magnetic bubble domain systems. In this device, chevron propagation paths are utilized. A pair of substantially parallel conductors are interconnected at appropriate locations via the chevrons in the respective propagation paths. The pair of conductors permits reduced amplitude requirements in the control current signal. In addition, a return path for the current signal is provided to simplify interconnection in major/minor loop chip configurations. The chevrons are arranged such that the apex of one chevron group is contained between the pair of conductor lines. The ends of adjacent chevron groups in another propagation path are disposed between the pair of conductor lines. Consequently, the magnetic bubble domain "sits" on the chevron ends longer whereby wider phase margins during a transfer operation are achieved. Annihilation of magnetic bubble domains can be achieved by reversing the current direction.

Abstract: A deep well drill is disclosed which utilizes as a prime mover a multistage hydraulic turbine. The system is self-propelled by means of a cylindrical clam shell assembly. The shell sections are spread apart and locked against the surrounding wall of the drilled hole by means of hydraulic cylinders. A hydraulic motor drives the turbine and drill assembly by means of a threaded shaft downward until fully extended. The clam shell is then retracted, and by reversing the hydraulic motor, follows the turbine drill downward until the start position is reached and the cycle is repeated.

Abstract: Three equidistantly spaced actuators are utilized to provide both tip and tilt positioning of a mirror mount backup plate to which a mirror is mounted. Two of the three actuators are preloaded differential ball-bearing screws driven by geared stepping motors. The third actuator is fixed thus providing a two axes mirror adjustment capability. The backup plate is suspended from the mirror mount base by specially designed flexures.