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Miller, R. O.

Publications and source records attributed to Miller, R. O..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Electrochemical behavior of 0.2 to 3 molar ferrous chloride-ferric chloride mixtures on edge-on pyrolytic graphite rotated disk electrodes

Potentiostatic determinations in various mixtures of FeCl2-FeCl3 with excess HCl show rest potentials that are 0.1 V less electropositive than the theoretical values from the formulated ratios of FeII to FeIII (probably as a result of complexing). The standard rate constant sub s. ranges between 0.0001 and 0.000 cm/sec. Tafel slopes b of roughly 0.12V per decade indicate single-electron exchange kinetics. No significant trend in either b or sub s was attributed to mixture composition. The higher sub s. values occurred with and edge-on pyrolytic graphite that had undergone a permanent surface change.

Miller, R. O.↗
NASA NTRS1975

Exploring the cell: Sodium (beta-alumina) cupric chloride - Aluminum chloride - Sodium chloride between 136 and 200 C

Experiments were done with a molten-salt catholyte (initially CuCl2 in AlCl3-NaCl) separated from molten Na by beta alumina. The open-circuit reduction potentials were 4.3 and 3 volts for Cu++ and Cu+, respectively. High polarization and nonrechargeability characterized the cell's operation. The cell's ohmic resistance during discharge was higher than what would be expected from only the ionic resistance of the beta-alumina.

Miller, R. O.↗
NASA NTRS1975

Oxygen reduction of several gold alloys in 1-molar potassium hydroxide

With rotated disk-and-ring equipment, polarograms and other electrochemical measurements were made of oxygen reduction in 1-molar potassium hydroxide on an equiatomic gold-copper (Au-Cu) alloy and a Au-Cu alloy doped with either indium (In) or cobalt (Co) and on Au doped with either nickel (Ni) or platinum (Pt). The results were compared with those for pure Au and pure Pt. The two-electron reaction dominated on all Au alloys as it did on Au. The polarographic results at lower polarization potentials were compared, assuming exclusively a two-step reduction. A qualified ranking of cathodic electrocatalytic activity on the freshly polished reduced disks was indicated: anodized Au Au-Cu-In Au-Cu Au-Cu-Co is equivalent or equal to Au-Pt Au-Ni. Aging in distilled water improved the electrocatalytic efficiency of Au-Cu-Co, Au-Cu, and (to a lesser extent) Au-Cu-In.

Miller, R. O.↗
NASA NTRS1972

Cadmium poisoning of oxygen reduction on platinum electrode in potassium hydroxide

Experiment with a rotating disk and ring apparatus showed no poisoning by cadmium in 8.5 M KOH, alone or with Cl(-) or CO3(=). Poisoning does not occur either in 0.1 M KOH supernatant at CdO, but a partially reversible poisoning results from .0001 M CdCl2 and traces of fatty acid are present. Evidence indicates that the catastrophic poisoning affects the four-electron O2 reduction more than it does the one-electron H3O(+) discharge.

Miller, R. O.↗