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Full-Text Articles in Engineering
A Mathematical Model Of The Self-Discharge Of A Ni-H2 Battery, Z. Mao, Ralph E. White
A Mathematical Model Of The Self-Discharge Of A Ni-H2 Battery, Z. Mao, Ralph E. White
Faculty Publications
A simple mathematical model is presented and used to characterize the self-discharge of a nickel oxyhydroxide(NiOOH) electrode in a hydrogen environment. This model includes diffusion of dissolved hydrogen in an electrolyte film which covers a flooded electrode, electrochemical oxidation of hydrogen, reduction of nickel oxyhydroxide, and changes of surface area and of porosity of the electrode during the self-discharge process. Although the self-discharge process is complicated, the predictions of the model are consistent with experimental results reported in the literature, which include linear relationships between the logarithm of hydrogen pressure and time and between the logarithm of the capacity remaining …
A Mathematical Model Of A Hydrogen/Oxygen Alkaline Fuel Cell, Michael C. Kimble, Ralph E. White
A Mathematical Model Of A Hydrogen/Oxygen Alkaline Fuel Cell, Michael C. Kimble, Ralph E. White
Faculty Publications
A mathematical model of a hydrogen/oxygen alkaline fuel cell is presented that can be used to predict polarization behavior under various potential loads. The model describes the phenomena occurring in the solid, liquid, and gaseous phases of the anode, separator, and cathode regions, assuming a macrohomogeneous, three-phase porous electrode structure. The model calculates the spatial variation of the partial pressures of oxygen, hydrogen, and water vapor, dissolved oxygen and hydrogen concentrations, electrolyte concentration, and the solid- and solution-phase potential drops. By developing a complete model of the alkaline fuel cell, the interaction of the various transport and kinetic resistances can …
Electrochemical Characterization Of Electronically Conductive Polypyrrole On Cyclic Voltammograms, Taewhan Yeu, Ken-Ming Yin, Jose Carbajal, Ralph E. White
Electrochemical Characterization Of Electronically Conductive Polypyrrole On Cyclic Voltammograms, Taewhan Yeu, Ken-Ming Yin, Jose Carbajal, Ralph E. White
Faculty Publications
Experimental and theoretical cyclic voltammograms for electronically conducting polypyrrole film are obtained from the identical conditions and compared to each other to characterize electrochemical behavior of the polymer. A comparison of the simulated and experimental cyclic yoltammograms shows quantitative agreement. The profiles of the dependent variables show that the switching process is governed by the availability of the counter ion to the polypyrrole electrode and the amount of electroactive sites. Sensitivity analysis shows that the double layer effects have more influence in the cyclic voltammograms than the electrokinetic effects.
In Situ Degradation Of Polyhalogenated Aromatic Hydrocarbons By Electrochemically Generated Superoxide Ions, E. E. Kalu, Ralph E. White
In Situ Degradation Of Polyhalogenated Aromatic Hydrocarbons By Electrochemically Generated Superoxide Ions, E. E. Kalu, Ralph E. White
Faculty Publications
The reduction of dioxygen in aprotic media yields superoxide ions which react with polyhalogenated aromatic hydrocarbons by nucleophilic substitution. The degradation of hexachlorobenzene to bicarbonates and chlorides using in situ generated superoxide ions was carried out at room temperature in a flow cell system equipped with a gas fed, porous electrode. The effects of current, electrolyte flow, and aprotic media on the extent of degradation of hexachlorobenzene are presented.