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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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At least 1,099 records · Page 61
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

Non-gassing nickel-cadmium battery electrodes and cells

Supposedly long-lived nickel-cadmium batteries often fail due to severe gassing on charge. In order to increase the lives of such cells attempts are being made to construct nongassing positive and negative electrodes. The gassing characteristics of both electrodes in negative limited cells were determined as a function of charge rate, charge temperature, and loading. Cycle life tests, up to 70 cycles, of some of the cells show they operate in a nongassing manner with very low degradation rates.

Luksha, E.↗
NASA NTRS1971

The effect of liquid configuration in porous gas electrodes.

Measurement of the influence of differential pressure on electrode activity in oxygen cathodes made up of beds of uniform silver spheres (156 micron diameter). The extent and nature of this dependence could be explained through use of the concept of pendular and funicular liquid configuration in the pore space of the electrode.

Katan, T.↗
NASA NTRS1972

The structure of hydrophobic gas diffusion electrodes.

The 'flooded agglomerate' model of the Teflon-bonded gas diffusion electrode is discussed. A mathematical treatment of the 'flooded agglomerate' model is given; it can be used to predict the performance of the electrode as a function of measurable physical parameters.

Giner, J.↗
NASA NTRS1974

Corrugated battery electrode

Performance of porous electrodes in batteries and other electrochemical cells is greatly improved when supports for active material have pores of uniform size, extending completely through electrodes, from side to side, with no interconnections between pores.

Mccallum, J.↗
NASA NTRS1972

Preparation of thin film silver fluoride electrodes from constituent elements

The feasibility of preparing thin-film metal fluoride electrodes from the elemental constituents has been demonstrated. Silver fluoride cathodes were prepared by deposition of silver on a conducting graphite substrate followed by fluorination under controlled conditions using elemental fluorine. The resulting electrodes were of high purity, and the variables such as size, shape, and thickness were easily controlled.

Odonnell, P. M.↗
NASA NTRS1973

Ion thruster with a combination keeper electrode and electron baffle

An ion thruster is described in which the cathode front end, surrounded by our insulator, is mounted flush with the front end of the flanged portion of the cathode pole piece. The thruster's baffle positioned in front of the cathode's front end supports the thruster's keeper electrode which is space apart and directed to the cathode's open end. The baffle is at the keeper's electrode potential.

Pawlik, E. V.↗
NASA NTRS1973

Morphology and capacity of a cadmium electrode - Studies on a simulated pore.

Conditions in a single pore of a battery plate were simulated by using a cadmium chip of millimeter dimensions covered with an electrolyte film of micron thickness. In situ microscopy was applied to study changes in the electrode morphology during charge and discharge. Passivation and increases in particle sizes due to precipitation and electrodeposition of dissolved cadmium species were found to cause profound loss in electrode capacity on repeated charge and discharge.

Will, F. G.↗
NASA NTRS1974

Finger recording electrode system for electrical impedance plethysmograph

System facilitates location of recording electrodes of impedance plethysmograph that is used for measuring flow of blood in finger segment; electrodes can be relocated accurately and volume of finger segment under study can be determined precisely. System minimizes movement artifacts in plethysmograph trace because finger segment is held firmly.

Montgomery, L. D.↗
NASA NTRS1974

Thermionic performance of a cesium diminiode with relatively impure 110-tungsten electrodes

Thermionic performance data from a miniature plane cesium diode (diminiode) with 110-tungsten electrodes are presented. The diminiode has a guard-ringed collector and a spacing of 0.23 mm. The data were obtained by using a computerized acquisition system. The diode was tested at increments between 1700 and 1900 K for the emitter, 694 and 1101 K for the collector, and 519 and 650 K for the reservoir. A maximum power density of 4.5 W/sq cm was obtained at an emitter temperature of 1900 K. This relatively low output probably results from high carbon and sodium impurities in the electrode materials.

Smith, A. L.↗
NASA NTRS1975

Long term flight electrodes

The reproducibility, stability, and methods of preparation for the various types and forms of biomedical electrodes are discussed. A critical and selective compilation of information on biological and/or physiological electrodes is presented. A discussion of plant hydrocolloids, clays, hydrophyllic colloids, synthetic waxes, and acrylic polymers is included.

Mosier, B.↗
NASA NTRS1975

Bonded electrodes for use on the external surface of spacecraft

A new bonding process is described which is suitable for applying electrodes to the external surfaces of spacecraft and sounding rockets. A polyimide material containing small, uniform glass spheres provides the necessary insulation and mechanical strength. The bonded electrodes are simple to construct and are shown to have good electrical, vacuum, and thermal properties.

Kendall, B. R. F.↗
NASA NTRS1977

Disposable biomedical electrode

Reusable recording cap equipped with compressible snap-on bioelectronic electrodes is worn by patient to allow remote monitoring of electroencephalogram and electro-oculogram waveforms. Electrodes can be attached to inside surface of stretch-textile cap at twelve monitoring positions and at one or two ground positions.

Frost, J. D., Jr.↗
NASA NTRS1976

Photoelectrolytic Production of Hydrogen Using Semiconductor Electrodes

Experimental data for the photoelectrolytic production of hydrogen using GaAs photoanodes was presented. Four types of GaAs anodes were investigated: polished GaAs, GaAs coated with gold, GaAs coated with silver, and GaAs coated with tin. The maximum measured efficiency using a tungsten light source was 8.9 percent for polished GaAs electrodes and 6.3 percent for tin coated GaAs electrodes.

Byvik, C. E.↗
NASA NTRS1976

The cadmium electrode: Review of the status of research

Investigations characterizing the negative cadmium electrode used in a nickel cadmium battery cell are summarized with citations to references where more detailed information is available. Emphasis is placed on data pertinent to aerospace applications. An evaluation of some of the published results of cadmium electrode research is included.

Gross, S.↗
NASA NTRS1977

Neutron monitoring and electrode calorimetry experiments in the HIP-1 Hot Ion Plasma

Results are presented for two diagnostic procedures on HIP-1: neutron diagnostics to determine where neutrons originated within the plasma discharge chamber and electrode calorimetry to measure the steady-state power absorbed by the two anodes and cathodes. Results are also reported for a hot-ion plasma formed with a continuous-cathode rod, one that spans the full length of the test section, in place of the two hollow cathodes. The outboard neutron source strength increased relative to that at the midplane when (1) the cathode tips were moved farther outboard, (2) the anode diameters were increased, and (3) one of the anodes was removed. The distribution of neutron sources within the plasma discharge chamber was insensitive to the division of current between the two cathodes. For the continuous cathode, increasing the discharge current increased the midplane neutron source strength relative to the outboard source strength. Each cathode absorbed from 12 to 15 percent of the input power regardless of the division of current between the cathodes. The anodes absorbed from 20 to 40 percent of the input power. The division of power absorption between the anodes varied with plasma operating conditions and electrode placement.

Reinmann, J. J.↗
NASA NTRS1976

Screening of redox couples and electrode materials

Electrochemical parameters of selected redox couples that might be potentially promising for application in bulk energy storage systems were investigated. This was carried out in two phases: a broad investigation of the basic characteristics and behavior of various redox couples, followed by a more limited investigation of their electrochemical performance in a redox flow reactor configuration. In the first phase of the program, eight redox couples were evaluated under a variety of conditions in terms of their exchange current densities as measured by the rotating disk electrode procedure. The second phase of the program involved the testing of four couples in a redox reactor under flow conditions with a varity of electrode materials and structures.

Giner, J.↗
NASA NTRS1976

Near-uv photon efficiency in a TiO2 electrode - Application to hydrogen production from solar energy

An n-type (001) TiO2 electrode irradiated at 365 nm was tested under anodic polarization. A saturation current independent of pH and proportional to light intensity has been observed. Accurate measurements of the incident power lead to a 60 per cent photon efficiency. A photoelectrochemical cell built with such an electrode, operated under solar irradiation without concentration, produced an electrolysis current of 0.7 mA/sq cm without applied voltage.

Desplat, J.-L.↗
NASA NTRS1979

resterilizable electrode for electrosurgery

Required properties of flexibility, electrical conductivity, tensile strength, and tear resistance of electrosurgical electrodes is retained through utilization of flexible-polymer/conductive particle composites for electrodes.

Engstrom, E. R.↗