Protective Properties of Zinc-Rich Coatings: An Impedance Method Estimate

The impedance of zinc-rich polymer coatings on steel in a 3-% NaCl solution is studied. The electrochemical behavior of the electrode is satisfactorily described by an equivalent circuit that contains a constant-phase element, which reflects fractal properties of the zinc surface in the binder. From the results of calculations of the circuit elements for metal-rich electrodes with different zinc contents computed are fractions of the active area of the surface of the coating and its fractal dimensionality.     

Conductivity of fused mixtures of lithium fluoride with cesium halides in the stratification region

Conductivity of fused mixtures of lithium fluoride with cesium halides is measured in the stratification region. The difference of conductivities of coexisting equilibrium phases is shown to increase with the increase in the halide anion radius at equal temperatures and to decrease with the increase in the temperature.     

Frequency dependence of potentials of minimum capacitance for electrodes of copper subgroup metals in alkali halide melts

The electrochemical impedance technique was use to obtain the potentials of the minimum capacitance of Cu, Ag, and Au electrodes in chlorides, bromides, and iodides of sodium, potassium, and cesium. Their dependence on the nature of the metal and electrolyte, temperature and ac signal frequency is studied. It is shown that the potential of the minimum capacitance tends at a decrease in the frequency to the zero charge potential measured under similar conditions. An assumption is ventured that the cause of this may be specific adsorption of halide ions on the electrode in the form of negatively charged dihalide complexes. It is found that in the systems where two minimums are observed, a decrease in the spacing between the cathodic and anodic minimums correlates with an increase in the strength of the metal-adsorbate bond.