Particle Sizing in Dense Suspensions With Multiwavelength Photon Migration Measurements.

Characterization of dense polydisperse suspensions, with mean diameters 143 and 226 nm and volume fractions ranging from 0.03 to 0.27, was conducted using time-dependent measurements of multiply scattered light. Frequency-domain photon migration measurements of isotropic scattering coefficients at wavelengths between 488 and 828 nm were found to agree with those predicted from the Mie theory and the polydisperse hard-sphere Percus-Yevick model. The wavelength-dependent isotropic scattering data were then used to successfully recover the particle size distribution and volume fraction of the suspensions, by minimizing a nonlinear least-squares problem. The mean particle size and volume fractions were recovered within an error range of 0-15.53 and 0-24%, respectively, compared with dynamic light scattering results and experimentally measured volume fractions. [ABSTRACT FROM AUTHOR]