Effective Diffusion Times in Multiple-Pulse PFG Diffusion Measurements in Porous Media

✍ Scribed by E.J. Fordham; P.P. Mitra; L.L. Latour

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 231 KB
• Volume: 121
• Category: Article
• ISSN: 1064-1858
• DOI: 10.1006/jmra.1996.0159

✦ Synopsis

Expressions for the effective diffusion times in multiple-gradient are of immediate utility in the analysis of experimental data. pulse diffusion measurements in liquid-saturated porous media These have been given, without derivation, in two previous are derived. This is necessary since the diffusion coefficient is time experimental papers (5, 6) to record the data analysis details. dependent. The results are needed for quantitative interpretation Correspondence has indicated that the derivation is of interof the results of PFG diffusion measurements using the multipleest to workers in porous-media diffusion, and this paper sets alternating-gradient schemes which are preferred for the majority out the essentials of this somewhat technical calculation.

of porous systems. The essence of the calculation and the results

Further discussion of the effects of finite pulse widths on for ''square'' and ''sine'' pulse shapes have appeared previously, the interpretation of PFG measurements in porous media but without derivation. The details of this somewhat technical may be found in (7).

calculation may be needed by users.