Chapter 3
initial values of surface relaxivity p, phase signal attenuation fraction к
and diffusivity of continuous oil phase Dcp.
2) Using Eq. [3.6] with surface relaxivity p to calculate drop size distribution;
Using Eq. [3.9] with Dcp and Dwater to calculate attenuation R0∏ and Rwater!
using Eqs. [3.12], [3.16] with drop size distribution to calculate attenuation
Remu∣; using Eq. [3.23] to calculate total attenuation of the emulsion R.
3) Performing least-square fitting of the experimental data Rexp for R until
norm of the difference ∣∣Reχp-^ll is smaller than tolerance to get fitted
values of all the parameters in step 1 ).
3.4. T1 weighted one-dimensional (1-D) MRI profile measurement
3.4.1. Introduction
In T1 weighted one-dimensional (1-D) MRI profile measurement, the
sequence consists of an rf 90o pulse, followed by an rf 180o pulse at time τ. A
spin-echo is collected at time tɛ. The rf 180o pulse is between two magnetic field
gradient pulses with strength g, as shown in Figure 3.6 [2]. The magnetic gradient
is along the vertical direction z. The first magnetic gradient pulse is referred as
coding gradient, which makes different spins along z direction have different
Larmor frequencies and precede out of phase. The second magnetic gradient
pulse is referred as reading gradient, which makes spins coherent and forms the
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