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arXiv · 1903.07194

Sensing Micro-colloid Concentration by Spectral Impedance Measurements and Relaxation Times Analysis

Roberto G. Ramírez-Chavarría·Celia Sánchez-Pérez
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Abstract

This paper presents an attractive method towards sensing and quantifying the concentration of dielectric particles suspended in a highly conductive medium. Fast electrical impedance spectroscopy (EIS) measurements were performed, based on an electrochemical setup and a non-parametric unbiased estimator. The impedance data are then mapped from the frequency domain to a time constant domain via the distribution of relaxation times (DRT) model. It is shown that application of DRT can systematically give a distribution function which is directly related with the concentration of micro-colloid samples. As a result, the samples were characterized by high sensitivity and resolution.

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Roberto G. Ramírez-Chavarría, Celia Sánchez-Pérez. 2019-03-17. Sensing Micro-colloid Concentration by Spectral Impedance Measurements and Relaxation Times Analysis. https://arxiv.org/abs/1903.07194

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