Differential dynamic and integral static light scattering for nondestructive testing of 3D disperse systems with nanoparticles

ABSTRACT In this contribution it is reported on the inverse optical problem for characterization oflatex nanopaticle water dispersionby two types of light scattering: differential dynamic and integral static (time average). Such measurements are nonde-structive, compatible and can provide useful information about the state of "ill-defined" three-dimensional disperse sys-tems (3D DS) with nano- and micro- particles.Keywords: 3D disperse systems, light scattering, polystyrene nanosphere 1. INTRODUCTION Physical, chemical and biological phenomena and processes in fmite structure of the nanoscale size range are now ofgreat interest. Development of in-situ and ex-situ instrumentation for characterization ofnanoparticles and their interfacesshould be based on new principles and phenomena not well understood at the nanometer scale. Nanoparticles having atleast one lengthscale ranging from molecular to micron exhibit improved and novel properties that are a direct result oftheir small size. Nanoparticle research is at the intersection of various scientific and technological areas, including parti-cle technology, colloids, aerosols, multiphase systems, solid state physics, chemistry and macromolecular science, mate-rials engineering, pharmacy, environment and health effects, biotechnology and biomedicine, sensors and electronics, etc.These studies need mutual approaches originated from different disciplines and technologies.Three-dimensional disperse systems (3D DS) are the systems of particles (disperse phase) in dispersive medium.Usually 3D DS are unstable. There are different processes in DS: aggregation, sedimentation, coalescence, flocculation,getero-aggregation, fractal aggregation, etc. Since light scattering is extremely sensitive to the parameters and size distri-bution of the scattering particles it is one of the best technique to control of the 3D DS state and to fmd the presence ofaggregates or debris.The 3D DS with nano- and micro- particles as disperse phase are so called "ill defined" systems and the solving ofinverse optical problem for light scattering is "ill-conditioned" (i.e. there are many particle distributions that correspond