Modeling the effects of RF penetration in magnetic resonance (MR) imaging requires a knowledge of the local values of conductivity and permittivity. The inverse problem of determining the electlic properties of the materid under investigation using the M R images themselves has not previously been addressed.W e review such an approach for the heterogeneous layer model and examine the parsmeter sensitivity l o geometry and signal-to-noise ratio. For a few-layer system, it is within the realm of present day M a systems to extract the electric properties 10 within 10% or better. Knowledge of the electrical propertis will then allow a better prediction of the R F penetration and power deposition at high fields.

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Magnetoelectric (ME) composite ceramics of NiFe2O4 (NFO) and lead zirconate titanate (PZT) were synthesized by a simple in situ processing based on a sol–gel method followed by a conventional sintering. X-ray diffraction patterns and scanning electron microscopy images revealed that this processing can produce two pure phases simultaneously. The in situ grown magnetic NiFe2O4 grains were well dispersed in the PZT matrix. The results demonstrated an attractive ME response of about 28.5 V cm−1 Oe−1 in the 0.35 NiFe2O4/0.65PZT at a resonance frequency of around 287 kHz.

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