It is intrinsically difficult to measure the size distribution of flocculated particles. Numerous papers show that the flocs break apart when sampling, so measurements must be made in situ. But this may not always be possible. In those circumstances, it becomes important to know how much the size distribution measured ex situ, from a sample, would differ from the in situ measurement, and if the ex situ measurement can be related to the in situ measurement.
de Lange et al. excellently addresses this in their pre-print ‘The Impact Of Flocculation on In Situ and Ex Situ Particle Size Measurements by Laser Diffraction’ doi: https://doi.org/10.22541/essoar.168319822.29525394/v1
Hint: It is impossible to return the ex situ samples to their original, in situ, state. Ex situ measurements are only useful for obtaining the particle size distribution of the primary particles.
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