Determination of Particle Size by Ultrasedimentation

Discrete particle size separation or fractionation is carried out in the strong gravitational field of rapidly rotating ultracentrifuges. Theoretical background and experimental technique are described in depth in the literature [17-19], While there 

Particle size distribution analyses in organic solvents may show dissolution and recrystallization effects when pigments with poor solvent fastness are measured. 

Recent ultrasedimentation techniques for pigment analysis have abandoned the two-layer principle. Measurements can now be taken directly on the aqueous dispersion itself, which alleviates a number of problems, such as the streaming effect. However, both the intricate instrumentation and the complex mathematical evalu- 

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