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A new mechanism of superfast motion of resistive domains in anisotropic superconductors is suggested. For bicrystals or sandwiches of anisotropic superconducting materials, the superfast motion is shown to arise due to the additional Joule heating of the kink regions of a resistive domain by eddy currents associated with them. Conditions under which the resistive domain in an anisotropic superconductor moves with a velocity up to the Fermi velocity, ∼10 8 cm s −1 , are discussed. As a result of the superfast motion, generation of electric oscillations of high amplitude with frequencies up to 10 10 Hz can take place. † Temporary address:

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Electrochemical properties of thin silicon oxy carbide films were investigated as anticorrosive coatings. The film was deposited on low carbon steel substrate by radio frequency capacitive coupled plasma technique using tetraethyl ortho silicate (TEOS) as a precursor and Ar was used as a carrier gas in dependence on the applied power. The chemical composition and morphological of the deposited films were examined by energydispersive X-ray spectroscopy (EDX) coupled with scanning electron microscopy (SEM). The SEM results confirm a pinhole-free layer of oxy carbide was formed on the steel surface after plasma treatment. The corrosion resistance of the coatings was analyzed by potentiodynamic polarization and electrochemical spectroscopy (EIS) in 3.5% NaCl solution at room temperature. The electrochemical results show remarkable corrosion resistance enhancement after plasma treatments. The corrosion current (icorr) is significantly reduced from 12 µA/cm 2 for the blank sample to 1 and 0.3 µA/cm 2 for treated samples at 50, and 100 W, respectively. A marked increase of the protective properties was detected by 100 W sample with protective efficiency more than 98 % at room temperature.

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