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The variation of the transition temperature with residual resistance of coldworked In and T1 shows a similar behaviour as in dilute alloy experiments. Subsequent annealing removes lattice defects in distinct steps and restores the properties of pure samples at temperatures below 250 ~ Some of the results can be interpreted in accordance with the model developed by MARKOWlTZ and KADANOFF on alloy experiments. Values for the anisotropy parameter (a251n=0.02 and (az)Tl=0.04 were obtained. The interpretation of the "valence" effect and the influence of stress is discussed.

A microwave cryostat is described, which enables us to measure the surface resistance of superconducting films in metastable states. In metastable disordered films often elevated transition temperatures are found. Surface resistance measurements can give information about electronic parameters of such films. In connection with dc-conductivity and critical magnetic field measurements, the mean free path, the penetration depth and the coherence length were determined in the metastable and the annealed state. These values have been compared with those expected from a free electron model.

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