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Abstract: Two-probe Hebb–Wagner polarization technique has been widely used to determine the partial electronic conductivity of an ionic conductor. The crucial, but often ignored pre-requisite with this technique is that the electronic over-potential at the electrodes be small enough to be neglected. In our own earlier experiences, however, this pre-requisite is not always true. In this study, we constructed a noble, 4-probe polarization cell, which allows measuring the true partial electronic conductivity without any electrode over-potential problem. We applied this new technique to 10m/o Gd-doped CeO2 (GDC) and compared the results with those from the conventional 2-probe technique. According to the comparison, electronic conductivity of GDC from 2-probe technique is always underestimated by 2–3 times while the 4-probe technique has turned out to be in perfect agreement with the estimated value from the total conductivity in its exclusively n-type regime. In this study we will report the experimental details of this noble 4-probe polarization technique as well as its viability in partial conductivity measurement. [Copyright &y& Elsevier]

Abstract: The validity of some rules in the classical theory of spin, which are followed by the Bargmann–Michel–Telegdi formula for a relativistic particle spin rotation in a constant homogeneous magnetic field, is analyzed. In the framework of the quantum theory, we give examples where these rules are violated. Consequences for polarization experiments are discussed. [Copyright &y& Elsevier]