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Using NMR to Measure Fractal Dimensions

D. Candela·Po-zen Wong
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Abstract

A comment is made on the recent PFG NMR measurements by Stallmach, et al. on water-saturated sands [Phys. Rev. Lett. 88, 105505 (2002)]. It is pointed out that the usual law for the time-dependent diffusion coefficient D(t) used by these authors is not valid for a fractal surface. It is shown that (1-D(t)/D0) \~ t^[(3-Ds)/2] at short times for a surface of fractal dimension Ds, where D0 is the bulk diffusion coefficient. Preliminary PFG NMR data on water saturated limestone and plastic beads are presented to illustrate this analysis.

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D. Candela, Po-zen Wong. 2002-04-19. Using NMR to Measure Fractal Dimensions. https://doi.org/10.1103/physrevlett.90.039601

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