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arXiv · 0812.3361

Correcting the polarization effect in low frequency Dielectric Spectroscopy

Camelia Prodan·Corina Bot
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Abstract

We demonstrate a simple and robust methodology for measuring and analyzing the polarization impedance appearing at interface between electrodes and ionic solutions, in the frequency range from 1 to $10^6$ Hz. The method assumes no particular behavior of the electrode polarization impedance and it only makes use of the fact that the polarization effect dies out with frequency. The method allows a direct and un-biased measurement of the polarization impedance, whose behavior with the applied voltages and ionic concentration is methodically investigated. Furthermore, based on the previous findings, we propose a protocol for correcting the polarization effect in low frequency Dielectric Spectroscopy measurements of colloids. This could potentially lead to the quantitative resolution of the $α$-dispersion regime of live cells in suspension.

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Camelia Prodan, Corina Bot. 2008-12-17. Correcting the polarization effect in low frequency Dielectric Spectroscopy. https://doi.org/10.1088/0022-3727/42/17/175505

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