Effects of interelectrode impedance in water conductivity measurements with capacitive electrodes
نویسندگان
چکیده
Capacitive electrodes overcome electrode polarization problems and enable noninvasive measurements hence they do not obstruct flow and avoid corrosion, wearing and soiling. However, their impedance is much higher than that of direct contact electrodes and, to reduce it, the measurement frequency must be increased, which worsens the effects of stray interelectrode impedance. In this paper, we analyse those effects when measuring water conductivity inside a plastic container and determine the more convenient frequency range to minimise measurement deviations. Keywords—water conductivity; capacitive electrodes; interelectrode capacitance; interelectrode resistance; shielding.
منابع مشابه
Effects of Stray Capacitance to Ground in Bipolar Water Impedance Measurements Based on Capacitive Electrodes
Liquid impedance measurements based on capacitive (or contactless) electrodes overcome electrode polarization problems but are affected by stray capacitance from the material being measured to ground, the same as measurements with direct-contact electrodes. This study shows that the effects of that capacitance depend on the impedance being measured and for bipolar impedance measurements they ...
متن کاملIterative Precise Conductivity Measurement with IDEs
The paper presents a new approach in the field of precise electrolytic conductivity measurements with planar thin- and thick-film electrodes. This novel measuring method was developed for measurement with comb-like electrodes called interdigitated electrodes (IDEs). Correction characteristics over a wide range of specific conductivities were determined from an interface impedance characterizati...
متن کاملA critical evaluation of direct electrical protein detection methods.
During the last decennia many protein-related electrical phenomena have been studied and applied in a variety of measuring systems, from simple metal electrodes with adsorbed proteins to sophisticated systems with lipid bilayers. Many of the investigations concern the monitoring of immuno reactions. The basic underlying electrical effects of the observed phenomena are the protein modulated diel...
متن کاملComparison of Binary and Ternary Compositions of Ni-Co-Cu Oxides/VACNTs Electrodes for Energy Storage Devices with Excellent Capacitive Behaviour
Electrochemical performance of binary and ternary oxides composed of Ni, Co and Cu produced over a 3-dimensional substrate of vertically aligned carbon nano-tubes (VACNT) as electrodes for aqueous energy sources, is reported and compared in this paper. VACNTs were fabricated inside a DC-plasma enhanced chemical vapor deposition chamber and composite materials fabricated by thermal decomp...
متن کاملIn situ spatially and temporally resolved measurements of salt concentration between charging porous electrodes for desalination by capacitive deionization.
Capacitive deionization (CDI) is an emerging water desalination technique. In CDI, pairs of porous electrode capacitors are electrically charged to remove salt from brackish water present between the electrodes. We here present a novel experimental technique allowing measurement of spatially and temporally resolved salt concentration between the CDI electrodes. Our technique measures the local ...
متن کامل