Electrochemical impedance has been used to study the adsorption at glassy carbon electrodes of guanine, its corresponding nucleoside, guanosine, and adenine. Impedance studies at different concentrations and applied potentials show clearly that all three bases are adsorbed on the electrode, blocking the surface. Irradiating the electrode with low-frequency (20 kHz) ultrasound whilst recording t...

During this program we have had several major accomplishments. These include finalizing our prior work on simple anisotropic surfaces consisting of discrete regions of homogeneous impedance values, and demonstrating them in the form of several useful structures. Examples include beam shifting structures, and scattering control surfaces. We have also developed a new method for patterning anisotr...

It is well recognized that label-free biosensors are the only class of sensors that can rapidly detect antigens in real-time and provide remote environmental monitoring and point-of-care diagnosis that is low-cost, specific, and sensitive. Electrical impedance spectroscopy (EIS) based label-free biosensors have been used to detect a wide variety of antigens including bacteria, viruses, DNA, and...

Title of Document: EVALUATION AND MODELING OF ELECTROCHEMICAL MIGRATION ON PRINTED CIRCUIT BOARDS Xiaofei He, PhD, 2014 Directed by: George Dieter Chair Professor Michael G. Pecht, Assistant Research Scientist Michael H. Azarian, Department of Mechanical Engineering Electrochemical migration (ECM) is the growth of conductive metal filaments on a printed circuit board (PCB) through an electrolyt...

In this paper, a problem on Rayleigh surface wave in an isotropic micropolar elastic solid half-space with impedance boundary conditions is investigated. It is assumed that the normal force traction, shear force traction and shear couple traction vary linearly with the normal displacement component, tangential displacement component and microrotation component multiplied by the frequency, where...

Apparatus has been designed and constructed for the measurement of the electric impedance of suspensions of Arbacia eggs in sea water to alternating currents of frequencies from one thousand to fifteen million cycles per second. This apparatus is simple, rugged, compact, accurate, and rapid. The data lead to the conclusions that the specific resistance of the interior of the egg is about 90 ohm...