Open AccessRapid measurements of diffusion using PFG: Developments and applications of the Difftrain pulse sequence
Author(s) -
Mitchell Jonathan,
Johns Michael L.
Publication year - 2009
Publication title -
concepts in magnetic resonance part a
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.229
H-Index - 49
eISSN - 1552-5023
pISSN - 1546-6086
DOI - 10.1002/cmr.a.20128
Subject(s) - pulsed field gradient , diffusion , pulse (music) , pulse sequence , characterization (materials science) , sequence (biology) , phase (matter) , nuclear magnetic resonance , flow (mathematics) , field (mathematics) , analytical chemistry (journal) , computational physics , chemistry , materials science , physics , mechanics , nanotechnology , optics , chromatography , thermodynamics , mathematics , biochemistry , organic chemistry , detector , pure mathematics
Pulsed‐field gradient (PFG) nuclear magnetic resonance (NMR) is one of the few experimental techniques that can determine directly mean square molecular displacements, allowing self‐diffusion coefficient of liquids to be derived. PFG measurements are used commonly for diffusion, flow, and microstructure characterization. However, these conventional PFG experiments are often time consuming, requiring the gradient strength or observation time to be incremented independently. Here we discuss how the rapid Difftrain pulse sequence has proved invaluable in the study of time sensitive systems by allowing multiple observation times to be probed in a single scan. Difftrain has been applied successfully to the study of emulsions, surfactant solutions, bead packs, and permeable rock cores. We discuss various implementations of the Difftrain pulse sequence, suggest suitable phase cycles, and review the applications to date. © 2009 Wiley Periodicals, Inc. Concepts Magn Reson Part A 34A: 1–15, 2009.