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Time domain reflectometry (TDR) is a technique that allows simultaneous estimates of apparent permittivity ([epsilon].sub.a]) and hence volumetric water content ([theta]) and bulk electrical conductivity ([[sigma].sub.a]). Difficulties arise for [theta] and [[sigma].sub.a] determination, however, when uncoated TDR probes (UP) are used in highly conductive media. This work shows that [[sigma].sub.a] can be estimated in highly conductive media using a TDR probe coated with a high-dielectric insulator (CP). To this end, the Dalton method for [[sigma].sub.a] estimations was applied to a 10-cm-long three-rod TDR probe insulated with a 0.2-mm-thick epoxy-ceramic composite coating with a relative permittivity, [[epsilon].sub.r], of 32.3. This method was calibrated on different NaCl--water solutions (0-15 dS [m.sup.-1]) and compared with the standard long-time TDR method for ([[sigma].sub.a] estimations using an UP. The method was subsequently used for determining [[sigma].sub.a] in four different soils with different values of [theta] and [[sigma].sub.a] (0-6 dS [m.sup.-1]) and again compared with the standard TDR procedure. The low error (RMSE = 1.5) for the comparison between the [[epsilon].sub.a] measured with the CP and that calculated with the analytical solution for coaxial probes indicates that the CP is accurate enough for [[epsilon].sub.a] estimations. For [[sigma].sub.a] values Abbreviations: CP, high-dielectric coated time domain reflectometry probe; DC, direct current; TDR, time domain reflectometry; UP, uncoated time domain reflectometry probe.

A powder-in-tube technique using cold rolling, drawing and annealing processes was utilized in fabricating uniform long length silver-clad monofilamentary BSCCO tapes. EDX, XRD, image analysis and scanning electron microscopy were employed in analyzing the effects of the starting BSCCO powders, the packing technique and the Ag addition. Electrical transport measurements reveal average values of Jc=12 kA/cm2 with a dispersion of +/-5% over a 1 m length.

Digital speckle pattern interferometry is used for detecting inhomogeneous heating in Y[Ba.sub.2][Cu.sub.3][O.sub.7-[delta]] coated conductors. The experiments have shown that the location of the initial hot spot leading to the complete transition to the normal state of the conductor is dependent on the sample cooling configuration and the results are compared with those obtained by direct electric field measurements along the sample in nitrogen vapor and liquid.