Appendix A
processing can be found in Mark Flaum’s thesis (Mark Flaum, Fluid and rock
characterization using new NMR diffusion-editing pulse sequences and two
dimensional diffusivity-T2 map, PhD Thesis, Rice University, Houston, 2006).
A.3. Parameters for 1-D T1 weighted MRI profile measurement
In 1-D T1 weighted MRI profile measurement, waiting time tw (RD in script)
between successive scans is the key parameter. An appropriate value for waiting
time tw should be chosen to make profile amplitudes of emulsified water between
that of bulk water and oil. If profile amplitudes of any two components are close
each other, in water/ oil fraction calculation, these two components are not
distinguishable, which will reduce the accuracy of the calculation.
Fig. A.1 (Fig. 3.17 in chapter 3) shows the amplitude profiles of bulk water, oil
and emulsified water. T1 for bulk water can be measured using INVREC sequence
(details can be found in Instruction Manual of MARAN). Detailed calibration for Ti
values of oil and emulsified water are discussed in chapter 3. T1 values for bulk
water, oil and emulsified water are 2.60 s, 0.63 s and 1.41 s, respectively. Waiting
time tw is 0.60 s. In this case, amplitude profiles of bulk water, oil, emulsified water
and fresh emulsion (1:1 w∕o) are different each other and distinguishable.
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