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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Three nand gate circuits are used to add error detection and reset logic circuitry for initiating and retaining the correct binary state in the flip-flop circuits of a ring counter. As the input signals are counted, the position of the specified state moves in ordered sequence around circuit loop.
Stainless steel crucible-shaped vessel permits rapid decomposition of silicates and other refractory compounds by acids at relatively low temperatures. The vessel is lined with tetrafluoroethylene fluorocarbon resin and sealed by a sheet of the same material retained in a stainless steel screw cap.
Rolling-type spacers in the form of steel balls retained in appropriate sleeves affixed at intervals to the exterior of the transfer line facilitate the installation of a vacuum-jacketed line. They act as standoffs to position the transfer line concentrically within the vacuum jacket line.
Dynamic-reservoir lubricating device supplies controlled amounts of lubricating oil to ball bearings during operation of the bearings. The dynamic reservoir lubricating device includes a rotating reservoir nut, a hollow cylinder filled with lubricating oil, flow restrictors and a ball bearing retainer.
Cooling of Rene 41 prior to welding reduces the incidence of cracking during post-weld heat treatment. The microstructure formed during the slow cooling rate favors elevated temperature ductility. Some vestiges of this microstructure are apparently retained during welding and thus enhance strain-age crack resistance in air.
Fiber glass material, placed between polyurethane foam insulation and the outer surfaces of cryogenic vessels, retains its resilience at cryogenic temperatures and provides an expansion layer between the metal surfaces and the polyurethane foam, preventing cracking of the latter.
Stress levels created in turbine stator components because of differential thermal expansion was eliminated by incorporation of a semifloating design, in which the stator vanes are retained by the outer ring assembly and radially piloted in the inner ring.
Remote, unattended means has been designed and reduced to practice that retains and then releases an attached load by means of a restrained cable. The cable is released by an electrical impulse on signal.
Nuclear radiation effects on performance of liquid hydrogen cooled ball and roller bearings, noting fluorocarbon resin retainer materials role
Elastic buckling and initial postbuckling of spherical caps under concentrated load indicate shell retains load carrying capacity
Multistep predictor-corrector method for numerical solution of ordinary differential equations retains high local accuracy and convergence properties. In addition, the method was developed in a form conducive to the generation of effective criteria for the selection of subsequent step sizes in step-by-step solution of differential equations.
Electrical characteristics of the mesh or screen electrodes used in electron tubes are improved by decreasing the shunt capacitance of the tube while retaining the close spacing needed for the required resolution. Vibrational characteristics are enhanced by raising the natural resonant frequency.
Printed circuit boards retaining as much copper as possible provide electromagnetic shielding between stages of the high frequency amplifiers and transmitters. Oscillation is prevented, spurious output signals are reduced, and multiple stages are kept isolated from each other, both thermally and electrically.
Split-half cover eliminates the surface marring and dirt penetration problems previously encountered during handling and cable assembly. Metal retaining ring slips over the two plastic halves to hold them in place.
Backward-diode pressure transducer retains the advantages of a tunneling mechanism, requires no shunting resistor, operates at a low voltage level, and consumes little power.
Spring loaded insert protects electrical connector pins from being bent due to improper mating, or probing the pins with a screwdriver. This device modifies existing electrical connectors using only springs and retaining pins.
Electromagnetically generated, high-dielectric tube forms a waveguide which retains the electromagnetic energy within the beam, the trapped beam establishes an optical frequency waveguide appropriate for its own conduction with minimum diffraction loss.
Releasable coupling device designed to receive and retain matching ends of electrical connectors