Dynamic fight scattering

The translational diffusion coefficient in Eq. 11 can in principle be measured from boimdary spreading as manifested for example in the width of the g (s) profiles although for monodisperse proteins this works well, for polysaccharides interpretation is seriously complicated by broadening through polydispersity. Instead special cells can be used which allow for the formation of an artificial boundary whose diffusion can be recorded with time at low speed ( 3000 rev/min). This procedure has been successfully employed for example in a recent study on heparin fractions [5]. Dynamic fight scattering has been used as a popular alternative, and a good demonstra-... 

That no indication of the significant influence of particle shape on FFF elution behavior has been published until recently may be attributed to the fact that the majority of the approximately 500 papers so far published have reported on spherical or nearly spherical samples, and that the studies on the non-spherical samples focused only on sample fractionation rather than on a quantitative assessment of physicochemical quantities. This problem can be solved if fractions from FFF are further characterized, for example, by dynamic fight scattering or if an independent detector for diffusion coefficients is available. 

Diiodo salicylic acid Dynamic fight scattering A,A-Dimethylformamide... 

Dynamic fight scattering provides a means to observe these fluctuations and Fig. 8.18 gives an example. For each scattering vector q a decay time t of the thus selected fluctuation, with wave vector k = q, was measured. Concentration fluctuations in liquids are always of diffuse nature, since all particles... 

Some popular methods of particle size analysis and their ranges of applicability are listed in Table 8.3. The methods used most often to analyze polymer emulsions, described below, are conveniently divided into three categories (a) ensemble techniques (e.g. laser diffraction (LD) and dynamic fight scattering (DLS)) (b) separation techniques (e.g. capillary hydrodynamic fractionation (CHDF) and disk centrifugation) (c) ultrahigh separation techniques (e.g. SPOS and electrozone sensing). 

Dynamic fight scattering has often been used in bulk liquid crystals for several different purposes. In most cases, the ratios of the viscoelastic coefficients were determined, according to the dispersion relation (4.8). In principle, from the amplitude of the non-normalised autocorrelation function one can also obtain the elastic constants themselves by using (4.7), but as it is difficult to measure absolute intensities in fight scattering, Frank elastic constants are usually obtained using other methods. 

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