Determination of particle mass density distribution

A new method for the determination of two characteristics of a sample of pa rticles, the correlation of particle mass density with particle size and th e distribution of particle mass density, is presented. The new method to me et these requirements is based on the combination of two optical particle s izing techniques where the measured particle characteristics have a differe nt dependence on particle mass density. Photosedimentation and laser dim-ac tion were chosen as suitable techniques for this goal. The determination of particle mass density by photosedimentation and laser diffraction is based on the fact that for each particle size class of the sample to be analysed the mass density can be calculated by an application of the Lambert-Beer l aw. The particle size distribution of the sample has to be known for the de termination of particle mass density, and it is measured by laser diffracti on. From this, two particle characteristics, the relationship of particle m ass density and particle size and the distribution of particle mass density , are obtained. The capacity of the algorithm and its limitations are demon strated by computational simulations including an error propagation analysi s. Experimental results are shown for homogeneous and heterogeneous materia ls.