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Odonnell, P. M.

Publications and source records attributed to Odonnell, P. M..

14 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1977

Anion exchange membranes for electrochemical oxidation-reduction energy storage system

Oxidation-reduction couples in concentrated solutions separated by appropriate ion selective membranes were considered as an attractive approach to bulk electrical energy storage. A key problem is the development of the membrane. Several promising types of anionic membranes are discussed which were developed and evaluated for redox energy storage systems. The copolymers of ethyleneglycoldimethacrylate with either 2-vinylpyridine or vinylbenzl chloride gave stable resistance values compared to the copolymer of vinylbenzlchloride and divinylbenzene which served as the baseline membrane. A polyvinylchloride film aminated with tetraethylenepentamine had a low resistance but a high ion transfer rate. A slurry coated vinylpyridine had the lowest ion transfer rate. All these membranes functioned well in laboratory cells at ambient temperatures with the acidic chloride oxidant/reductant system, Fe 3, Fe 2/Ti 3, Ti 4.

Odonnell, P. M.↗
NASA NTRS1975

Kinetics of the fluorination of zinc

The reaction between zinc metal and fluorine gas can be described by a parabolic rate law. This reaction is both temperature and pressure dependent. Simple kinetics are complicated by the considerable vaporization rate for zinc at temperatures above 300 C (573 K).

Odonnell, P. M.↗
NASA NTRS1975

Conductivities of the ionic complexes of two cyclic polyethers

The conductivities of the solid potassium thiocyanate complex of both dicyclohexyl-18-crown-6 and dibenzo-18-crown-6 were measured at 300K (27 C). Saturated aqueous potassium thiocyanate and graphite were used as ion-transporting and ion-blocking electrodes, respectively. The ionic conductivity predominated for both samples, but it was many orders of magnitude smaller than the value previously reported. The ionic conductivity of the dicyclohexyl complex (the better conductor) was 0.000003 ohm/cm. Crown complexes, in general, do not appear promising as potassium ion solid electrolytes contrary to claims in the patent literature.

Fielder, W. L.↗
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 NTRS1972

Reactivity of simulated lunar material with fluorine

Simulated lunar surface material was caused to react with fluorine to determine the feasibility of producing oxygen by this method. The maximum total fluorine pressure used was 53.3 kilonewtons per square meter (400 torr) at temperatures up to 523 K (250 C). Postreaction analysis of both the gas and solid phases indicated that the reaction is feasible but that the efficiency is only about 4 percent of that predicted by theory.

Odonnell, P. M.↗
NASA NTRS1969

The fluorination of metals.

Elemental fluorine reactions with Ni, Cu, Fe, Ti, Be Al, Zr and Ag, giving reaction rate constants, activation energies, etc

Odonnell, P. M.↗
NASA NTRS1967

Beryllium fluoride film protects beryllium against corrosion

Film of beryllium fluoride protects beryllium against corrosion and stress corrosion cracking in water containing chloride ion concentrations. The film is formed by exposing the beryllium to fluorine gas at 535 degrees C or higher and makes beryllium suitable for space applications.

O ~donnell, P. M.↗