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arXiv · 2210.06016

NMR surface relaxivity in a time-dependent porous system

Neil Robinson·Razyq Nasharuddin·Einar O. Fridjonsson·Michael L. Johns
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Abstract

We demonstrate an unexpected decay-recovery behaviour in the time-dependent $^{1}\mathrm{H}$ NMR relaxation times of water confined within a hydrating porous material. Our observations are rationalised by considering the combined effects of decreasing material pore size and evolving interfacial chemistry, which facilitate a transition between surface-limited and diffusion-limited relaxation regimes. Such behaviour necessitates the realisation of temporally evolving surface relaxivity, highlighting potential caveats in the classical interpretation of NMR relaxation data obtained from complex porous systems.

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Neil Robinson, Razyq Nasharuddin, Einar O. Fridjonsson, Michael L. Johns. 2023-03-24. NMR surface relaxivity in a time-dependent porous system. https://doi.org/10.1103/physrevlett.130.126204

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