Eddy current disruption: effect on nuclear magnetic resonance coil impedance and power loss.

Abstract:

:We present a theoretical development and experimental verification of a description of power loss and sample resistance for a lossy sample in a nuclear magnetic resonance radio frequency coil for a sample geometry where the eddy current streamlines are disrupted from their usually assumed circular paths. Specifically treated is the case of a lossy hemisphere. The problem is solved for two orientations; with the induction parallel and perpendicular to the flat surface of the hemisphere. Results of this analysis as well as those for the full sphere as presented by Hoult and Lauterbur are compared with observation for a variety of sample conductivities and orientation.

journal_name

Med Phys

journal_title

Medical physics

authors

Harpen MD

doi

10.1118/1.596336

subject

Has Abstract

pub_date

1989-09-01 00:00:00

pages

781-4

issue

5

eissn

0094-2405

issn

2473-4209

journal_volume

16

pub_type

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