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Analysis of sample power loss in MRI gradient fields.

M D Harpen
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Abstract

A derivation of the power dissipation in a conducting spherical sample in a time-dependent gradient magnetic field is presented and the predicted values are compared with those observed in an experimental apparatus consisting of a four-element saddle coil and a Maxwell coil pair. The derived expressions for power dissipation are shown to agree with values obtained experimentally via Q measurements of the loaded coils. It is also shown the large rapidly fluctuating gradient fields encountered in echo planar imaging produce relatively small levels of absorbed power.

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Magnetic Resonance ImagingMathematicsModels, TheoreticalJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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M D Harpen. Analysis of sample power loss in MRI gradient fields.. https://doi.org/10.1118/1.596677

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