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Published on: September 5, 2018
Novel Electrochemical Flow Sensor Based on Sensing the Convective-Diffusive Ionic Concentration Layer
Sinwook Park1, Ramadan Abu-Rjal1, Leon Rosentsvit1
1Faculty of Mechanical Engineering, Micro- and Nanofluidics Laboratory , Technion - Israel Institute of Technology , Technion City 3200000 , Israel.
Abstract:
Presented is a novel flow sensor based on electrochemical sensing of the ionic concentration-polarization (CP) layer developed within a microchannel-ion permselective membrane device. To demonstrate the working principle of the electrochemical flow sensor, the effect of advection on the transient and steady-state ionic concentration-polarization (CP) phenomenon in microchannel-Nafion membrane systems is studied. In particular, we focused on the local impedance, measured using an array of electrode pairs embedded at the bottom of the microchannel, as well as the total current across the permselective medium, as two approaches for estimating the flow. We examined both a stepwise application of CP under steady-state flow and a stepwise application of flow under steady-state CP.
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