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Summary form only given. The authors used the pyroelectric properties of beta-phase polyvinylidene fluoride (PVdF) to construct a relatively fast response cryogenic thermometer. The temperature dependence of the pyroelectric coefficient of 9 mu m and 28 mu m PVdF films was measured over the temperature range from 20 K to 300 K. Repeated cycling of the films between room temperature and 20 K did not appear to damage the films or change the values of the pyroelectric coefficients. When a sample of lipids was dipped in Freon 12 at 115 K, the cooling rate was found to be 989 +or- 21 Ks/sup -1/. The results show that a thin PVdF film can be used as an accurate and cheap rapid-response temperature sensor at cryogenic temperatures. >

We have measured the in-phase component of the low frequency a.c. impedance of the d.c. current-induced intermediate state in indium-lead alloy wires. The theory developed by Gauthier and Rochon, which is based on London's model of the intermediate state, predicts theoretical values considerably larger than our observations, particularly near the critical current. By modifying the Gauthier-Rochon theory, to a first approximation, to take account of the Baird-Mukherjee model of the intermediate state we obtain reasonably good agreement with our measurements.

Landau has recently suggested that a static periodic structure of the direct current-induced intermediate state cannot explain experimental measurements and he has revived the dynamic structure originally proposed by Gorter. We point out that experimental results can, for the most part, be understood reasonably well on the basis of the Baird-Mukherjee static model and that some of these results do not support the possibility of a Gorter type dynamic structure.