Detection of the high eigenmodes of spin diffusion in porous media
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Updated: Oct 11, 2026

In Situ Monitoring of Diffusion of Guest Molecules in Porous Media Using Electron Paramagnetic Resonance Imaging
Published on: September 2, 2016
Song1
1Schlumberger-Doll Research, Old Quarry Road, Ridgefield, Connecticut 06877, USA.
Abstract:
The dynamics of spin diffusion in a fluid is governed by the Torrey-Bloch equations, and the solution is often expressed mathematically in an eigenmode expansion. We report an experimental demonstration of the excitation and detection of a wide range of eigenmodes in porous media by exploring the inhomogeneous internal magnetic field in the pore space. The nodal character of the eigenfunctions of the high eigenmodes was clearly observed. The methodology of excitation and detection of the high eigenmodes may be used to better characterize pore geometry.
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