Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 19 of 19 for “"impedance response"”.
-
Analysis of Electrode Geometric Parameters on AC Impedance Response
<p>Electrochemical Impedance Spectroscopy (EIS) is a powerful and proven tool for analyzing AC impedance response. A conventional three electrode EIS method was used to perform the investigation in the present study. Saturated potassium chloride solution was used as the electrolyte, and three …
-
Electroding Methods for in situ Reverse Osmosis Sensors
… interfacial regions, thus sensor impedance. Platinized polymer graft sensors were shown to be sensitive to protein fouling. Electrodes were characterized by their electrical properties, SEM and XPS. Assembled sensors were evaluated for sensitivity to electrolyte concentration and …
-
Electrochemical impedance spectroscopy of proton exchange membrane fuel cell stacks
Electrochemical Impedance Spectroscopy (EIS) is applied to a small, four cell Proton Exchange Membrane (PEM) fuel cell stack to examine the stack response as the load current changes. The measured stack response is compared to a simulated response generated by a stack model that has been developed …
-
Modeling and characterization of ionic polymer transducers for sensing and actuation
… work in this area has focused on the actuation response, therefore the focus of this research is on providing a better understanding of the sensing and impedance responses of the ionic polymer transducer. Using transport theory as the basis, a set of analytical models are developed to …
-
Yeast-based impedance biodosimetry for retrospective assessment of radiation exposures
… exposures following radiological accidents using impedance biodosimetry. The radiation response of S. cerevisiae was examined by using cellular metabolic activity and impedance as a means to evaluate dose. A novel dosimeter design was developed to allow impedance measurements to be performed on …
-
Investigation of synthetic methods for preparation of 2<sup>o</sup>-amino derivatives of 5-amino- 1, 10-phenanthroline: Applications to Cu<sup>+2</sup> based impedance sensors
… interdigitated electrode array chips in standard impedance and impedance resonance-based Cu<sup>2+</sup> sensors. Potential applications include monitoring Cu<sup>2+</sup> leaching from anti-fouling coatings on ship hulls. The importance of the planned secondary alkyl amino derivatives will be to …
-
Comparison of standard impedance spectroscopy response to aqueous metal ions using plain vs. surface derivatized gold interdigitated electrodes
… linkage, resulting in significant changes in impedance response in the presence of Cu2+ solutions. However, questions regarding the stability of the primary amine-based dithiocarbamate self-assembled monolayer, reproducibility of the raw impedance and phase angle data, and possible variation …
-
High Frequency Modeling and Experimental Analysis for Implementation of Impedance-based Structural Health Monitoring
… for implementation on real world structures is impedance-based health monitoring. An in-service system is envisioned to include on board processing and perhaps wireless transfer of data. Ideally, a system could be produced as a slap-on or automatically installed addition to a structure. The …
-
Damage identification using inductive learning
… examples. The method utilizes as much dynamic-response data as is available, ordering this information to find the best data with which to discriminate among a set of damage states available for dynamic testing. This method takes into account the inherent variabilities in the damage …
-
Development and characterization of conducting polymer actuators
… the dynamic mechanical compliance and electrical impedance of polypyrrole as a function of charge is difficult, since the compliance depends upon the excitation frequency as well as the electrochemical stimulus. Here, we have developed novel experimental techniques that use stochastic input …
-
Reliability of Tibial Measurement with Mechanical Response Tissue Analysis
Mechanical response tissue analysis (MRTA) provides a noninvasive means of estimating the cross-sectional bending stiffness (EI) of long bones, and thus can serve as a predictor of bone strength. Estimates of bone bending stiffness are derived from the point impedance response of a long bone to low …
-
Non-intrusive two-phase flow regime identification and transport characterization in microchannels subject to uniform and non-uniform heat input
… is measured in this work using a custom-designed impedance-based sensor with electrodes on opposing walls of a single microchannel, a 'crosswise' geometry. The impedance response of the sensor is calibrated against the time-averaged void fraction determined via high-speed flow visualizations. The …
-
Considerations on the use of Impedance Spectroscopy for the Detection of Virions Trapped in Quadrupolar Microelectrode Arrays
The impedance response of a quadrupolar microelectrode array was studied over a wide frequency range to determine whether particles captured at the center of the array could be detected impedimetrically. The microelectrode array (denoted as DEP chip) uses dielectrophoretic forces to concentrate …
-
Electrically-Small Antenna Performance Enhancement for Near-Field Detuning Environments
… antennas near kaH1 have achieved multiple-octave impedance bandwidths when utilizing volume-efficient designs. Significant advances in both the power and miniaturization of microelectronics have created a second possible approach to enhance bandwidth. Frequency agility, via switch tuning of …
-
Non-destructive Microstructural Evaluation Of Yttria Stabilized Zirconia, Nickel Aluminides And Thermal Barrier Coatings Using Electrochemical Impedance Spectroscopy
… of this study is to develop electrochemical impedance spectroscopy (EIS) as a Non-destructive evaluation (NDE) technology for application to TBCs. To have a better understanding of the multilayer TBCs using EIS they were divided into individual layers and EIS were performed on them. The …
-
Sensing in 3D Printed Neural Microphysiological Systems
… quantify the dynamics of disease progression or response to treatment. The first objective of process improvement was addressed both through modification of the 3D printing system itself and through modeling of process physics. A new manifold was implemented which enabled on-the-fly mixing of …
-
The electrical impedance responses of protective oxide scales on stainless steels that are immersed in molten lead-bismuth-eutectic alloy at temperatures up to 600°C
This research explored the electrical impedance responses of oxide scales on stainless steel, when the steel was immersed in molten lead-bismuth-eutectic alloy (LBE) at high temperatures (up to 600°C). LBE is a candidate coolant for future fast-neutron-spectrum nuclear reactors and for …
-
Application of Sweep Frequency Response Analysis and Locked-Rotor Test for Stator Winding Inter-Turn and Broken Rotor Bar Fault Detection of Squirrel-Cage Induction Motors
… affected coil or winding. The sweep frequency response analysis (SFRA) approach, developed by Dick and Erven [12], allows for the detection of small changes in the windings due to the effect of short-circuits by analysing the winding impedance over its bandwidth. This technique is mostly used …
-
Theoretical and experimental study of solid oxide fuel cell (SOFC) using impedance spectra
… diffusion resistance extracted from no bias AC impedance. Anode-supported SOFCs with Ni-yttria-stabilized zirconia (YSZ) anode were used to study the multicomponent gas transport in porous electrodes. A fuel gas mixture of H₂-H₂O-N₂ was fed to the anode and AC impedance data were measured at …