Research of resolution effect for the width of incidence beam in the measurement of photosedimention technique;

The experimental research was made according to the granulometric principle on wet ground fine cement by optical sedimentation granulometer, and the factors which influence the particle size measurment were studied.

Errors analysis of testing sediment grain size by the methods of laser way and extinction sedimentation way;

Based on the Stokes formula and Lambert-Beer Law, a series of recurrence formulae were advanced to calculate particle size distribution from the data obtained by disc centrifuge photosedimentation, with the effect of extinction efficiency of particles and the radial dilution during sedimentation considered.