Paper abstract bibtex

A polarization modulation linear dichroism technique has recently been developed and applied to studies of the particle microdynamics associated with subjecting dilute colloidal suspensions to time-dependent flows. In this paper, we compare the abilities of the Rayleigh and Rayleigh-Gans light scattering approximations to represent experimental dichroism data in terms of calculations based on known hydrodynamic models. In particular, the importance of considering finite particle size in the light scattering theory is investigated. Calculations of the conservative linear dichroism and of the average particle orientation angle are carried out for dilute suspensions subjected to transient simple shear flow in the absence of Brownian motion and in the presence of weak Brownian motion. For both situations, only small differences in the features associated with the particle orientation statistics of the simulation occur between the Rayleigh and the Rayleigh-Gans calculations over a wide range in particle geometry. In particular, the calculation of the average particle orientation angle is found to be insensitive to the choice of light scattering treatment. Generally, we infer from these simulations that the additional complexity of the Rayleigh-Gans treatment is usually not warranted for the analysis of typical rheo-optical data from dilute suspensions. \$\backslash$textcopyright\ 1987.

@article{ Frattini:1987tp, abstract = {A polarization modulation linear dichroism technique has recently been developed and applied to studies of the particle microdynamics associated with subjecting dilute colloidal suspensions to time-dependent flows. In this paper, we compare the abilities of the Rayleigh and Rayleigh-Gans light scattering approximations to represent experimental dichroism data in terms of calculations based on known hydrodynamic models. In particular, the importance of considering finite particle size in the light scattering theory is investigated. Calculations of the conservative linear dichroism and of the average particle orientation angle are carried out for dilute suspensions subjected to transient simple shear flow in the absence of Brownian motion and in the presence of weak Brownian motion. For both situations, only small differences in the features associated with the particle orientation statistics of the simulation occur between the Rayleigh and the Rayleigh-Gans calculations over a wide range in particle geometry. In particular, the calculation of the average particle orientation angle is found to be insensitive to the choice of light scattering treatment. Generally, we infer from these simulations that the additional complexity of the Rayleigh-Gans treatment is usually not warranted for the analysis of typical rheo-optical data from dilute suspensions. \{$\backslash$textcopyright\} 1987.}, annote = {Correspondence Address: Fuller, G.G.; Department of Chemical Engineering, Stanford University, Stanford, CA 94305, United States}, author = {Frattini, P L and Fuller, G G}, journal = {Journal of Colloid and Interface Science}, number = {2}, pages = {335--351}, title = {{Conservative dichroism of a sheared suspension in the Rayleigh-Gans light scattering approximation}}, url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-0023437432\&partnerID=40\&md5=ca97301fd07acde13a313e0d64de41c8}, volume = {119}, year = {1987} }

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