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BH Suits

Publications and source records attributed to BH Suits.

3 recordsLinked to original sources
PubMed1998

Noise-immune coil for unshielded magnetic resonance measurements

A modified split-loop resonator that is electrically balanced and that has no magnetic dipole moment is shown to be relatively immune to environmental noise. Using a magnetic resonance surface coil of this design for 14N NQR at 3.4 MHz, it is demonstrated that magnetic resonance measurements can be made in the laboratory without additional RF shielding and with less than a 2 dB increase in the rms noise. Compared to more traditional designs, the modified split-loop resonator showed a net 17-dB gain in sensitivity for unshielded measurements. Copyright 1998 Academic Press.

Journal Article↗
PubMed1998

NMR Imaging Using Second Order Quadrupole Broadened Resonances.

Theoretical and experimental results for NMR imaging measurements of powdered materials using the +(1/2) to -(1/2) transition of (1/2)-integerspin nuclei in the presence of a very large second-order electric quadrupolar broadening are presented. An "effective spin-(1/2)" formalism is developed to account for additional effects due to the presence of quadrupolar interactions comparable in size to the Zeeman interaction. A large (7.9 mT/cm-A, with a maximum current of approximately 20 A), rapid ( approximately 30 µs) pulsed linear gradient field is used with echoes and phase encoding techniques to obtain images in the limit gammaH1 is much narrower than the NMR linewidth. A one-dimensional projection of the second-order quadrupolar perturbed, 4-MHz-wide, +(1/2) left and right arrow -(1/2) transition for 63Cu in Cu2O powder is presented as an example. An experimental one-dimensional projection of a sample containing Cu2O and YBa2Cu3O6.7 is also presented. Copyright 1998 Academic Press.

Journal Article↗