Sedimentation Coefficient

Since the terms r, pP, pM and y as given in eqns [13]—[15] are constant for a given particle in a homogeneous medium, the sedimentation rate, dx/dt, is proportional to rn2x. This proportionality is often expressed in terms of the sedimentation coefficient, S, which is simply a measure of the sedimentation velocity per unit of centrifugal force. For a given set of run conditions, the sedimentation coefficient, Sr, may be calculated as:

The sedimentation coefficient, S, has the dimensions of seconds and is expressed in Svedberg units equal to 10~13 s. Its value is dependent on the particle being separated, the centrifugal force and the properties of the sedimentation medium. While adequate for a given set of run conditions, it is sometimes useful to compare sedimentation coefficients obtained under differing conditions and/or sedimentation media by reference to the behaviour of the particle in water at 20°C, S20,w:

where the subscripts T and M denote the experimental temperature and medium, respectively.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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