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dc.contributor.advisor Johnson, G. Allan en_US
dc.contributor.author Nouls, John Claude en_US
dc.date.accessioned 2009-05-01T18:19:20Z
dc.date.available 2009-05-01T18:19:20Z
dc.date.issued 2009 en_US
dc.identifier.uri http://hdl.handle.net/10161/1068
dc.description Dissertation en_US
dc.description.abstract <p>In magnetic resonance microscopy, insufficient signal-to-noise ratio currently limits imaging performance. Superconducting probes can potentially increase the sensitivity of the magnetic resonance experiment. However, many superconducting probes failed to entirely deliver the expected increase in signal-to-noise ratio. </p><p>We present a method based on finite-element radiofrequency simulations. The radiofrequency model computes several figures of merit of a probe, namely: i) the resonant frequency, ii) the impedance, iii) the magnetic field homogeneity, iv) the filling factor, and v) the sensitivity. The probe is constituted by several components. The method calculates the electromagnetic losses induced by every component within the probe, and identifies the component limiting the sensitivity of the probe. Subsequently, the probe design can be improved iteratively.</p><p>We show that the sensitivity of an existing superconducting Helmholtz pair can be improved by increasing the filling factor of the probe and cooling the radiofrequency shield, which was implemented in the design of a new superconducting probe. The second probe exhibits a sensitivity three times as high, leading to improved imaging performance.</p> en_US
dc.format.extent 3225005 bytes
dc.format.mimetype application/pdf
dc.language.iso en_US
dc.subject Engineering, Biomedical en_US
dc.subject Health Sciences, Radiology en_US
dc.subject coil en_US
dc.subject magnetic resonance en_US
dc.subject microscopy en_US
dc.subject simulation en_US
dc.subject superconducting en_US
dc.title Superconducting Radiofrequency Probes for Magnetic Resonance Microscopy, Simulation and Experiments en_US
dc.type Dissertation en_US
dc.department Biomedical Engineering en_US

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