Particle size distributions in mesh cuts and microscopically estimated volumetric shape factors

When particle size distribution parameters are calculated from sieve analys is, it is generally assumed that the distribution within the particle cut i s either linear producing a mean particle size equal to the average of the mesh openings (1-3), or that a more proper number is the geometric mean of these two apertures. It is shown here that particles within a mesh cut are not linearly distributed, but rather may be normally, log-normally or bipha sic combinations of the two. Three compounds were examined in this fashion, and results are reported here.