The name is absent

Chapter 3

2) The surface relaxivity (p) and the bulk relaxivity (1∕T₂,b∪∣k) of the drop
phase are known. T₂,bulk can be easily measured from a CPMG
experiment on a bulk sample of the drop phase.

3) T₂,bulk for the dispersed phase is indeed single-valued and not a
distribution of characteristic bulk relaxation times.

4) Two independent sets of T_2j,∙ - f_i values can be resolved from the T₂
distribution of the emulsion for the oil and water phases, respectively.

The minimum and maximum drop sizes that can be determined via CPMG
are, respectively^[5]:

⅛_in ≈ 6∕‰ - ⅛_ax ≈ min{T> / 2p, 2SNRpT^_bulk / e}                     [3.7]

Here T₂,_min is the smallest T₂ of water drops measured by CMPG. SNR is
signal to noise ratio of the measurement. D is diffusivity of dispersed phase.

Using the data reported in reference ^[5], the drop size range which can be
measured by CPMG is 16 nm to 580 μm ^[5].

But in some cases, such as water in light oil emulsion, T₂ distribution of
dispersed water phase is very close to that of continuous oil phase. Thus CPMG
method is not appropriate because the T₂ distribution is not distinguishable. The
alternative methods for estimating the water fraction and drop size distribution will
be discussed in the following sections.

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