Measuring very small concentrations in organic suspensions by coherent light scattering

The single act light scattering anisotropy is conveniently described using the Henyey-Greenstein phase function when the scattering centers dimension is comparable or bigger than the wave length. When the concentration increases, a different phase function can be used. For a certain scattering angle the calculated light scattering intensity variation with the optical depth of the target is analyzed and compared with the experimental data recorded on mud in aqueous suspension. The results suggest a very fast method for measuring very small concentration in suspensions, in the range of mu g/l.