Ight scattering

T ight scattering in dense media is caused by fluctuations in the local " dielectric tensor c (i). In 1922 Brillouin (2) predicted that thermal acoustic phonons would lead to such fluctuations and hence to light scattering. In addition, the scattered light should be shifted in frequency because the phonons are moving. The frequency shift is given by ... 

Fig. 2.29 Optical microscopy photograph of a PS and poly(vinyl methyl ether) (PS/PVME) T-(j> combinatorial sample (library) after 16 h of annealing, showing the lower critical solution temperature (LCST) cloud-point curve. White points are conventional /ight-scattering cloud points measured independently on separate uniform samples (Meredith et al. 2000)...

Stepanek, P. (1993) Data Analysis in Dynamic l ight Scattering, in Dynamic Light Scattering The Method and Some Applications, (ed. W. Brown), Oxford Science Publications, Oxford, p. 177. 

In conclusion, the revealed maximum of light scattering in the direction parallel to pore axis resulting in spatial anisotropy of emergent 1 ight is coimected with non-isotropic distribution of DOPS. This effect may be utilized in creation of light sources with directed radiation based on PAA membranes. 

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