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The microwave dielectric properties of Ca(0.85)Nd(0.1)TiO(3) - LnAlO(3) (Ln = Sm, Gd, Dy, Er) ceramics are investigated in this paper. The structural characteristics of the specimens were evaluated by Rietveld refinement of Xray diffraction (XRD) patterns and high-resolution transmission electron microscopy (HRTEM). Solid solution limits were dependent on the ionic radius of Ln(3+) ions. With the decrease of the ionic radius of the Ln(3+) ions, the thermal stability of the resonant frequency decreases. This can be attributed to the increased level of oxygen octahedral distortion caused by the increase in the B-site bond valence in the ABO(3) perovskite structure. The dielectric constant (K) and the quality factor (Qf) of the specimens were dependent on the polarizability and grain size, respectively.

Investigates an equivalence circuit model for characterizing a person's electrical properties. It is not straightforward to compare skin-impedance data of various research groups because the impedance depends very sensitively on measurement conditions such as the shape, size, material, and contact pressure of the electrodes, the skin humidity due to sweat, the applied current, the shape of the wave, and even the psychological condition of the subject. With these subtleties in mind, we show the impedance data taken by various groups and our data (shown with curves). Data of other groups are scattered around our curve.