flow employed. In no way has the selection of porous structure, cell or flow geometry been optimized; these should be subjects of future investigations. ConclusionsThis study has demonstrated the feasibility of the electrochemical reduction of EAQ dissolved in an organic solvent from an aqueous-continuous suspension flowing past an electrode. With a sufficiently high degree of turbulence, current densities and current efficiencies of industrial interest can be achieved. Although the present results are insufficient for the design or evaluation of a large-scale application of this process, it would appear that cathodic reduction of EAQ (and other water-insoluble organic compounds) in two-phase systems warrants further evaluation in the laboratory.

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Rechargeable Alkaline Manganese Dioxide Batteries. Part 1. In situ X-Ray Diffraction Investigation of the H+/γ-MnO2 (EMD-Type) Insertion System.-The influence of electrochemical H+ insertion/deinsertion on the structure of γ-MnO2 (electrochemically deposited) is studied. Proton insertion up to 0.4 H+ per MnO2 results in an expansion of the unit cell due to the reduction of Mn4+ to larger Mn3+ ions. For insertion levels of 0.5-0.8 H+ per MnO2, loss of long-range order and formation of a quasi-amorphous state is observed. The amorphous phase is reduced to γ-Mn2O3 (or Mn3O4) and to Mn(OH)2 upon further H+ insertion. During recharge, Mn(OH)2 is oxidized to γ-Mn2O3 which leads to a poor cycling behavior. The best cycle life is obtained when the discharge is limited to 0.5 H+ per MnO2, i.e. the γ-MnO2 structure is retained. -(MONDOLONI, C.; LABORDE, M.; RIOUX, J.; ANDONI, E.; LEVY-CLEMENT, C.; J. Electrochem. Soc. 139 (1992) 4, 954-959; Lab. Phys. Solides Bellevue, CNRS, F-92195 Meudon, Fr.; EN)