{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T23:18:09Z","timestamp":1772234289316,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2010,6,9]],"date-time":"2010-06-09T00:00:00Z","timestamp":1276041600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Thin film microfabrication technique was employed to fabricate a platinum based parallel-electrode structured impedance sensor. Electrochemical impedance spectroscopy (EIS) and equivalent circuit analysis of the small amplitude (\u00b15 mV) AC impedance measurements (frequency range: 1 MHz to 0.1 Hz) at ambient temperature were carried out. Testing media include 0.001 M, 0.01 M, 0.1 M NaCl and KCl solutions, and alumina (~3 \u03bcm) and sand (~300 \u03bcm) particulate layers saturated with NaCl solutions with the thicknesses ranging from 0.6 mm to 8 mm in a testing cell, and the results were used to assess the effect of the thickness of the particulate layer on the conductivity of the testing solution. The calculated resistances were approximately around 20 M\u03a9, 4 M\u03a9, and 0.5 M\u03a9 for 0.001 M, 0.01 M, and 0.1 M NaCl solutions, respectively. The presence of the sand particulates increased the impedance dramatically (6 times and 3 times for 0.001 M and 0.1 M NaCl solutions, respectively). A cell constant methodology was also developed to assess the measurement of the bulk conductivity of the electrolyte solution. The cell constant ranged from 1.2 to 0.8 and it decreased with the increase of the solution thickness.<\/jats:p>","DOI":"10.3390\/s100605847","type":"journal-article","created":{"date-parts":[[2010,6,9]],"date-time":"2010-06-09T11:22:42Z","timestamp":1276082562000},"page":"5845-5858","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Microfabricated Thin Film Impedance Sensor &amp; AC Impedance Measurements"],"prefix":"10.3390","volume":"10","author":[{"given":"Jinsong","family":"Yu","sequence":"first","affiliation":[{"name":"Purdue University Calumet, Hammond, IN 46323, USA"}]},{"given":"Chung-Chiun","family":"Liu","sequence":"additional","affiliation":[{"name":"Case Western Reserve University, Cleveland, OH 44106, USA"}]}],"member":"1968","published-online":{"date-parts":[[2010,6,9]]},"reference":[{"key":"ref_1","unstructured":"Corrosion Theory Available online: http:\/\/corrosion-doctors.org\/Principles\/Theory.htm (accessed on 20 January 2008)."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1125","DOI":"10.1016\/0013-4686(90)80027-L","article-title":"A specific aspect of impedance measurements in low conductivity media. 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