NMR imaging applied to various studies of porous media

In Situ ESEM Examination of Microstructural Changes of an Apple Tissue Sample Undergoing Low-Pressure Air-Drying Followed by Wetting

“…A number of studies have been directly targeted at moisture transfer. [7][8][9][10][11][12][13] It has been illustrated that the simple receding evaporation front assumption may not be a realistic proposition. [10,11] There was no sharp front of evaporation observed.…”

A review of non-invasive imaging methods and applications in contaminant hydrogeology research

“…The distribution of two or more imiscible fluids can be measured by either selective excitation of different magnetically susceptible nuclei in each fluid, or by selective excitation of each fluid based on differences in T 1 or T 2 . Apparent diffusion coefficients, dispersion and advective velocities of selected nuclei can be imaged by applying pusle sequences that are sensitive to motion of the target nuclei (Pope and Yao, 1993; Fukushima, 1999), or by using a phase contrast agent as a tracer (Guillot et al, 1991; Greiner et al, 1997). …”

“…Guillot et al, 1991; Greiner et al, 1997; Irwin et al, 1999, 2000; Yoon et al, 2008). At the pore scale, Kutsovsky et al (1996) applied a flow encoding pulse sequence to measure the axial velocity profile in the pore space of 6 mm glass beads packed in a column (4cm ID).…”

“…In other applications, MRI has also been used to measure ion diffusion through water saturated porous media (Pearl et al, 1991; Baumann et al, 2000), dispersion (Guillot et al, 1991; Seymour and Callaghan, 1997; Amin et al, 1997; Stapf et al, 1998; Manz et al, 1999a, b; Deurer et al, 2004), density dependent flow in porous media (Pearl et al, 1993; Hoffman et al, 1996; Oswald et al, 2002; Oswald and Kinzelbach, 2004), and water flow in rock fractures (Mansfield and Issa, 1994; Dijk et al, 1999; Dijk and Berkowitz, 1999). Oswald et al (2002) imaged density driven flow in a 20cm 3 Plexiglas tank filled with 1.2mm glass beads and freshwater flow above saltwater using Cu 2+ as contrast agent, at a spatial resolution of 2.5×2.5×4 mm 3 (1.5T magnet).…”

Guest Editorial

“…A number of studies have been directly targeted at moisture transfer. [4][5][6][7][8][9][10] It has been illustrated that the simple receding evaporation front assumption may not be a realistic proposition, [7,8] though some earlier studies suggested it was the case for some hygroscopic materials. [11] There was no sharp front of evaporation observed in the latest MRI studies.…”