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We have presented conductivity spectra at different temperatures for mixed network former silver borophosphate glasses. By mapping the conductivity spectra onto time dependence of the mean square displacement of mobile ions in the framework of linear response theory, we have obtained two characteristic lengths of ion dynamics viz characteristic mean square displacement at which crossover from diffusive to subdiffusive ion dynamics and spatial extent of localized motion of mobile silver ions occur. We have shown that the mixed network effect in these glasses is correlated to these characteristic lengths which are strongly influenced by the Coulomb repulsion between the mobile silver ions as well as the interaction between the mobile ions and the glass network.

Nickel-tungsten nanocrystalline coatings were electrodeposited from a Watts type bath onto a copper substrate, at different current densities selected from activation, mixed and diffusion controlled regions in the cathodic scan plot at room temperature. The results confirm that tungsten codeposition proceeds via the adsorption and reduction of complexes produced in the bulk of solution. The coatings obtained were single phase solid solutions and their grain sizes increased with current density. A cauliflower-type surface morphology with highest hardness was obtained when the current density was in the activation controlled region. The surface morphology obtained in the mixed controlled region was distorted, and then converted to a nodular morphology in the diffusion controlled region. In the mixed control region, coatings with the highest corrosion resistance were obtained due to the lowest exchange current density for water reduction.

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