2.0 *0.2 V vs. SCE . c 1.0-c 300 400 SO0 600 Wavelength/nm Fig. 4. Action spectra of TiO2-free polypyrrole film (a) and TiO2incorporated polypyrrole films (b, c) taken in 0.5M KCI under electrolysis at 0.2 and -0.4V vs. SCE. The polypyrrole films given by (a), (b), and (c) are the same as those shown in Fig. 3.role takes place with the involvement of electrolyte cations. This implies that the anion-adsorbed TiO2 in the film acts as a fixed dopant as in the case of Nafion-polypyrrole composite (15), and electrolyte cations work as the charge compensators in the redox process of the polymer films.

Li3PS 4 crystallizes in the orthorhombic system, space group Prima, with a = 13.066 (3), b = 8.015 (2), c = 6.101 (2)A, V=639/ka, z=4, dm = 1.85, dx= 1.87Mg m -3. With Mo Kt~ radiation (2 = 0.71069 ,~,/t = 1.5 mm-~), the structure was refined to R = 0.046 with 255 independent reflexions (0 < 30 °). Tetrahedral PSIanions (mean P-S length 2.050 ]~) are centered on mirror planes; three kinds of Li + ions are revealed in the asymmetric unit: Li(1) in a fully filled site (tetrahedral coordination: Li...S ~_ 2.46/~); and Li(2) and Li(3) with occupancy factors of 0.7 and 0.3 0567-7408/82/071887-04501.00 respectively, so that diffusion of Li + through Li(2)-Li(3)--Li(2) tunnels with a 2.52]k jump between vicinal sites could be expected.

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The effect of thiourea, urea and guanidin on zinc deposits obtained from chloride baths under continuous current conditions are described and discussed. The corrosion behaviour of the deposits was investigated in an aerated 3.5% NaCl solution; anodic polarization curves, polarization resistance (R p ) measurements and weight-loss studies were performed. The corrosion resistance of zinc deposits improved in the presence of urea. The deposit morphology was analyzed using Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) was used to determine the preferred crystallographic orientations of the deposits. The preferred crystallographic orientations of zinc deposits (112) do not change in the presence of urea and guanidin except for an increase in the peak intensity of the (112) plane. In the presence of thiourea, zinc deposits crystallise in two textures; (100) and (110). The influence of each additive and the difference between additives on the zinc deposits are also discussed.