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Results for “Anodes”
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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Electric battery and method for operating same Patent
Elimination of two step voltage discharge property of silver zinc batteries by using divalent silver oxide capacity of cell to charge anodes to monovalent silver state
Temperature reducing coating for metals subject to flame exposure Patent
Anodizing method for providing metal surfaces with temperature reducing coatings against flames
Reliability studies in semiconductor fabrication
Profiling procedures including computer program (OLS) for measuring junction depth in anodic oxidation - semiconductor fabrication reliability studies
Rapid mass transport to electrodes in foamed electrolyte
Rapid mass transport to Pt electrodes in foamed electrolytes, examining current density-anode overpotential relationship
Large impulses of self-magnetic origin
Self magnetic impulses in gas discharge configuration as function of current and anode- cathode radii ratio
A liquid radiation detector with high spatial resolution
Detector, using point anode, minimizes problem of oblique tracks by permitting construction of very thin counter. Detector is useful in cosmic ray and high energy physics research and X-ray and neutron diffraction technology.
Silver-chlorine fuel cell: A concept
Fuel cell regenerated by photochemical reduction enables novel slurry system to transport particles of reduced silver between regenerator section and anode. Fundamental reactions which provide electrical power from the fuel cell are given.
Improved operation of rechargeable oxygen electrodes
Procedure for enhancing operating life and performance of oxygen electrodes in rechargeable metal-oxygen batteries and hydrogen-oxygen fuel cells is discussed. Accumulation of refractory anodic oxide layer and inhibiting effects on oxygen reduction are described. Improvements in service life of batteries by following procedure are explained.
Al/Cl2 molten salt battery
Molten salt battery has been developed with theoretical energy density of 5.2 j/kg (650 W-h/lb). Battery, which operates at 150 C, can be used in primary mode or as rechargeable battery. Battery has aluminum anode and chlorine cathode. Electrolyte is mixture of AlCl3, NaCl, and some alkali metal halide such as KCl.
Automatic method of measuring silicon-controlled-rectifier holding current
Development of automated silicon controlled rectifier circuit for measuring minimum anode current required to maintain rectifiers in conducting state is discussed. Components of circuit are described and principles of operation are explained. Illustration of circuit is provided.
Research on rechargeable oxygen electrodes
Studies were carried out on a number of factors which may influence the behavior of the platinum electrocatalyst of oxygen electrodes for use in rechargeable metal-oxygen batteries or hydrogen-oxygen fuel cells. The effects of pretreatments for various potentials and added ionic species, which could be present in such systems, were studied with reguard to: (1) the state of surface oxidation, (2) platinum dissolution, (3) the kinetics of oxygen evolution and reduction (including the role of hydrogen peroxide), and (4) changes in porous electrode structure. These studies were carried out on smooth platinum, platinized platinum, and Teflon-bonded platinum black electrodes in carefully purified electrolyte solutions. The main factors which appear to affect rechargeable oxygen electrode performance and life are: (1) the buildup of a refractory anodic layer on extended cycling, and (2) the dissolution of platinum.
Temporal survey of electron number density and electron temperature in the exhaust of a megawatt MPD-Arc thruster
Temporal and radial profiles are obtained 30 cm downstream from the anode for two peak arc currents (11.2 kA and 20 kA) and for various auxiliary magnetic fields (0, 1.0 T, and 2.0T) using the Thomson scattering technique. Average density and temperature are relatively constant for over 100 microseconds with significant fluctuations. Radial profiles obtained are relatively flat for 4 cm from the axis. Compared to earlier 20 cm data, the exhaust density has decreased significantly, the average temperature (4.6 eV) has not changed, and the density hole with an auxiliary magnetic field has enlarged.
The development of a noncryogenic nitrogen/oxygen supply technique
A development program was conducted in two phases to define the characteristics and requirements of an electrochemical oxygen/nitrogen supply technique for space station application. In Phase 1, electrode formulations and structures suitable for use as anodes in an oxygen/nitrogen generator were experimentally investigated. A one-man model oxygen/nitrogen generator integrated with a space cabin atmosphere simulator was fabricated and successfully tested in Phase 2. Data from these tests were used to update a computer routine model of the cabin atmosphere control using the oxygen/nitrogen generator technique. A specification and preliminary design for a 12-man oxygen/ nitrogen generation system was prepared.
Development of a position sensitive X-ray detector for use in a light weight X-ray diffractometer
A position sensitive proportional counter for use in an X-ray diffractometer is developed to permit drastic reductions in the power and weight requirements of the X-ray source and the elimination of the power, weight, and complexity of a moving slit. The final detector constructed and tested has a window spanning 138 and a free standing anode curved along an arc of 7.1 cm radius. Demonstration spectra of a quartz sample in a Debye-Sherrer geometry indicate a spatial resolution of 0.4 - 0.5 mm (0.3 - 0.4 theta). The lunar diffractometer consumed 25 watts in the X-ray generator and weighed about 20 pounds.
An electrochemical model for hot-salt stress-corrosion of titanium alloys
An electrochemical model of hot-salt stress-corrosion cracking of titanium alloys is proposed based on an oxygen-concentration cell. Hydrogen embrittlement is proposed as the direct cause of cracking, the hydrogen being generated as the results of the hydrolysis of complex halides formed at the shielded anode of the electrochemical cell. The model found to be consistent with the diverse observations made both in this study and by many investigators in this field.
Evaluation of a pulsed quasi-steady MPD thruster and associated subsystems
The performance of quasi-steady magnetoplasmadynamic (MPD) thrusters at high power levels is discussed. An axisymmetric configuration is used for the MPD thruster, with various cathode and anode sizes, over a wide range of experimental conditions. Thrust is determined from impulse measurements with current waveforms, while instantaneous measurements are made for all other variables. It is demonstrated that the thrust produced has a predominately self-magnetic origin and is directly proportional to the square of the current. The complete set of impulse measurement data is presented.
Development of techniques and associated instrumentation for high temperature emissivity measurements
The progress during the sixth quarterly period is reported on construction and assembly of a test facility to determine the high temperature emittance properties of candidate thermal protection system materials for the space shuttle. This facility will provide simulation of such reentry environment parameters as temperature, pressure, and gas flow rate to permit studies of the effects of these parameters on the emittance stability of the materials. Also reported are the completed results for emittance tests on a set of eight Rene 41 samples and one anodized titanium alloy sample which were tested at temperatures up to 1600 F in vacuum. The data includes calorimetric determinations of total hemispherical emittance, radiometric determinations of total and spectral normal emittance, and pre- and post-test room temperature reflectance measurements.