Dispersing Powder Samples for Size Characterization Studies

These can be cleaned and used over and over again because of the robust construction. As in the case of the Nuclepore type filters the fineparticles trapped by the filter remain on the surface and can be readily examined by image analysis. 

6 Dispersing Powder Samples for Size Characterization Studies 

In an earlier section I gave the reader the advice that they should never spend time and effort on characterizing a powder sample until they had discussed, with the group requesting the characterization study, the way in which the powder had been sampled and that only representative samples should be studied in depth. In the same way, when I was running a service laboratory, I always used to make the statement You disperse the powder, and I will characterize it. This is because in many methods of size characterization the powder sample has to be dispersed in a liquid or in a small drop of oil on a glass slide. The way in which the dispersion is carried out can drastically effect the size measurement. (Dispersing aerosols for characterization is discussed in Chapter 6.) 

Isolock samplers are available from Bristol Engineering Company, 204 South Bridge St., Box 696, Yorkville, IL 60560. 

Washington, Particle Size Analysis in Pharmaceutics and other Industries, Theory and Practise. Ellis Heywood, A Division of Simon Shuster International, Markey Cross House, Cooper Street, Chicester, West Sussex, England, 1992. 

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