Mariner IV space data automation system /SDAS/ computer reliability.
Mariner IV Space Data Automation System /SDAS/ computer reliability design, pellet component concept, testing, interconnection and welding techniques
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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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Thermal decomposition of yttrium-doped silver carbonate.
Yttrium effect on rate of thermal decomposition of silver carbonate powder and pressed pellets by isothermogravimetric analysis, examining water vapor, Co 60 gamma radiation and temperature effects
Rand, E.↗
Differential photo effects in gallium arsenide- metal junctions.
Alloying pairs of metal pellets to n and p type semiinsulating GaAs, discussing photo effects
Viehmann, W.↗
Feasibility study on isostatic pressing of pyrrones Final report
Compression molding technique for manufacturing Pyrrone pellets by isostatic pressing
Bradbury, E. J.↗
Determination of bonding parameters and inspection techniques for cadmium-to-stainless steel bonds and assembly of two capsule housings Final report
Bonding parameters and quality control for cadmium-stainless steel clad fuel pellet containment vessel production
Gripshover, P. J.↗
Support structure for irradiated elements Patent
Supporting structure for simultaneous exposure of pellets to X rays
Nasuti, A. J.↗
Solidus boundary in the InAs-AlAs pseudobinary system
InAs-AlAs pseudobinary system solidus boundary determination from pellet phase diagram
Foster, L. M.↗
Fabrication techniques for organic electrolyte battery
Experiments in fabrication and testing of silver chloride electrodes for use in organic electrolyte batteries are discussed. Electrodes were fabricated by pelletizing, sintering, hot press binding, and paste binding silver chloride on expanded metal grids of nickel or silver. Each technique was investigated by statistically designed factorial experiment.
Mcdonald, G. D.↗
Initiation system for low thrust motor igniter
A test program was carried out to demonstrate an igniter motor initiation system utilizing the bimetallic material Pyrofuze for a solid propellant rocket with controlled low rate of thrust buildup. The program consisted of a series of vacuum ignition tests using a slab burning window motor that simulated the principal initial ballistic parameters of the full scale igniter motor. A Pyrofuze/pyrotechnic igniter system was demonstrated that uses a relatively low electrical current level for initiation and that eliminates the necessity of a pyrotechnic squib, with its accompanying accidental firing hazards and the typical basket of pyrotechnic pellets. The Pyrofuze ignition system does require an initial constraining of the igniter motor nozzle flow, and at the low initiating electrical current level the ignition delay time of this system was found to be quite sensitive to factors affecting local heat generation or loss rates.
Strand, L. D.↗
some new techniques in passive contaminant analysis of space environment simulation chambers
A passive contamination analysis technique in surface sampling for space simulation was developed and evaluated. The KBr pelletizing technique was extended to include heavy oils for infrared analysis. Transmittance and specular reflectance measurements at 2000 A wavelength were found very sensitive to contamination.
Wolff, C. M.↗
Design, fabrication, and testing of an external fuel (UO2), full-length thermionic converter
The development of a full-length external-fuel thermionic converter for in-pile testing is described. The development program includes out-of-pile performance testing of the fully fueled-converter, using RF-induction heating, before its installation in the in-pile test capsule. The external-fuel converter is cylindrical in shape, and consists of an inner, centrally cooled collector, and an outer emitter surrounded by nuclear fuel. The term full-length denotes that the converter is long enough to extend over the full height of the reactor core. Thus, the converter is not a scaled-down test device, but a full-scale fuel element of the thermionic reactor. The external-fuel converter concept permits a number of different design options, particularly with respect to the fuel composition and shape, and the collector cooling arrangement. The converter described was developed for the Jet Propulsion Laboratory, and is based on their concept for a thermionic reactor with uninsulated collector cooling as previously described. The converter is double-ended, with through-flow cooling, and with ceramic seals and emitter and collector power take-offs at both ends. The design uses a revolver-shaped tungsten emitter body, with the central emitter hole surrounded by six peripheral fuel holes loaded with cylindrical UO2 pellets.
Schock, A.↗
Regenerable thermal control and carbon dioxide control techniques for use in advanced extravehicular protective systems
The most promising closed CO2 control concept identified by this study is the solid pellet, Mg(OH2)2 system. Two promising approaches to closed thermal control were identified. The AHS system uses modular fusible heat sinks, with a contingency evaporative mode, to allow maximum EVA mobility. The AHS/refrigerator top-off subsystem requires an umbilical to minimize expendables, but less EVA time is used to operate the system, since there is no requirement to change modules. Both of these subsystems are thought to be practical solutions to the problem of providing closed heat rejection for an EVA system.
Williams, J. L.↗
Fabrication of fuel pin assemblies, phase 3
Five full size and eight reduced length fuel pins were fabricated for irradiation testing to evaluate design concepts for a fast spectrum lithium cooled compact space power reactor. These assemblies consisted of uranium mononitride fuel pellets encased in a T-111 (Ta-8W-2Hf) clad with a tungsten barrier separating fuel and clad. Fabrication procedures were fully qualified by process development and assembly qualification tests. Detailed specifications and procedures were written for the fabrication and assembly of prototype fuel pins.
Keeton, A. R.↗
Irradiation of TZM: Uranium dioxide fuel pin at 1700 K
A fuel pin clad with TZM and containing solid pellets of uranium dioxide was fission heated in a static helium-cooled capsule at a maximum surface temperature of 1700 K for approximately 1000 hr and to a total burnup of 2.0 percent of the uranium-235. The results of the postirradiation examination indicated: (1) A transverse, intergranular failure of the fuel pin occurred when the fuel pin reached 2.0-percent burnup. This corresponds to 1330 kW-hr/cu cm, where the volume is the sum of the fuel, clad, and void volumes in the fuel region. (2) The maximum swelling of the fuel pin was less than 1.5 percent on the fuel-pin diameter. (3) There was no visible interaction between the TZM clad and the UO2. (4) Irradiation at 1700 K produced a course-grained structure, with an average grain diameter of 0.02 centimeter and with some of the grains extending one-half of the thickness of the clad. (5) Below approximately 1500 K, the irradiation of the clad produced a moderately fine-grained structure, with an average grain diameter of 0.004 centimeter.
Mcdonald, G. E.↗
Unrestrained swelling of uranium-nitride fuel irradiated at temperatures ranging from 1100 to 1400 K (1980 to 2520 R)
Six fuel pins were assembled, encapsulated, and irradiated in the Plum Brook Reactor. The fuel pins employed uranium mononitride (UN) in a stainless steel (type 304L) clad. The pins were irradiated for approximately 4000 hours to burnups of about 2.0 atom percent uranium. The average clad surface temperature during irradiation was about 1100 K (1980 deg R). Since stainless steel has a very low creep strength relative to that of UN at this temperature, these tests simulated unrestrained swelling of UN. The tests indicated that at 1 percent uranium atom burnup the unrestrained diametrical swelling of UN is about 0.5, 0.8, and 1.0 percent at 1223, 1264, and 1306 K (2200, deg 2273 deg, and 2350 deg R), respectively. The tests also indicated that the irradiation induced swelling of unrestrained UN fuel pellets appears to be isotropic.
Rohal, R. G.↗
Review of controlled fusion research using laser heating.
Development of methods for generating high laser pulse energy has stimulated research leading to new ideas for practical controlled thermonuclear fusion machines. A review is presented of some important efforts in progress, and two different approaches have been selected as examples for discussion. One involves the concept of very short pulse lasers with power output tailored, in time, to obtain a nearly isentropic compression of a deuterium-tritium pellet to very high densities and temperatures. A second approach utilizing long wavelength, long pulse, efficient gas lasers to heat a column of plasma contained in a solenoidal field is also discussed. The working requirements of the laser and various magnetic field geometries of this approach are described.
Hertzberg, A.↗
Improved fabrication of electrolytic capacitors
After processing parts for assembly, insulative cup is fitted to bottom of can, then electrolytic solution consisting of white sulfuric acid gel is inserted into can. Pellet is put in can and is fitted tightly into cup. Finally, bead weld is formed between can and header plug.
Gamari, F. J.↗
Development of a ruggedized 20-watt, 2.3- gigahertz transistor
This program was to develop a ruggedized transistor capable of meeting the following CW objectives at 2.3 gigahertz: a power output of 20 watts, a power gain of 6 db, and an efficiency of 40 percent. Devices developed produced the following CW performance at 2.3 gigahertz: a power output of 23 watts, a power gain of 7.7 db, and an efficiently of 40.0 percent. This performance was achieved with an eight-cell TA8407 transistor design having the following modifications: a thin pellet, high-frequency diffusion, high-level emitter ballasting, an optimized emitter-bonding configuration for uniform power sharing, and a package that provides for some internal matching through the use of distributed line techniques.
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