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Surfactant Titration of Kaolin Slurries using ζ-Potential Probe

January 2001

Authors:

The electroacoustic sensor probe contains a piezoelectric transducer with a critical frequency of 3-MHz and a sensing electrode which is placed on the surface of the transducer. This electrode is separated from the external reference electrode with a non-conducting rigid ceramic insert. Internal electric impedance between these electrodes can be selected depending on the conductivity range of the samples by means of an internal transformer. The transformer is selected such that the input impedance is significantly less than the external impedance of the sample such that the resultant signal is proportional to the short circuit current. This transformer is located just behind the central electrode in order to minimize the stray capacitance.

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Fundamentals of Interface and Colloid Science Vol. II: Solid–Liquid Interface

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J. J. Lyklema

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Two piezoelectric sensor effectiveness coefficients that provide a quantitative measure of effectiveness for piezoelectric materials which are being used for sensing strain (voltage sensor), or strain-rate (current sensor) are introduced. The use of these coefficients for selecting sensor materials is illustrated through a numerical example

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Reactively sputtered piezoelectric aluminum nitride (AlN) films for flexural plate wave (FPW) electroacoustic sensors equipped with buried interdigital transducers (IDTs) for sensing in liquids were fabricated and characterized. In order to assess the crystallographic and elastic film properties, residual film stress, and piezoelectric response, comprehensive analyses were performed on AlN layers ... [Show full abstract] and bimorph AlN structures, including X-ray diffraction, atomic force microscopy, and nanoindentation, in combination with analysis of the piezoelectric charge coefficient d33,f. To demonstrate the applicability of the optimized AlN films to electro-acoustic devices, IDT equipped devices were fabricated and characterized by means of laser Doppler vibrometry.

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April 2011 · The Journal of the Acoustical Society of America

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