Optical techniques light scattering

FODLS (fiber-optic dynamic light scattering) Lab and pilot scale emulsion polymerization reactions [116-1181 Non-invasive, no dilution necessary/Only average particle size, multiple scattering not fully solved [119] Emulsion polymerization. Promising technique that has not reached maturity. No industrial applications. 

In electro-optical measurements, one determines essentially an electrical dipole moment which is related to the number and the spatial distribution of mobile ions in the vicinity of a colloid surface. This technique - light scattering in the presence of an electrical field - was abundantly us in the investigation of the electrical properties of colloids dispersed in water. Extensive monographs on colloid electro-optics were published (7-2). In recent years, the effect of water soluble polymers on the behaviour of hydrosols (especially colloids of mineral or metallic origin) began to raise interest. Polymers partly because of their large... 

There are no standard tests for measuring the onset of asphaltenes precipitation. Among the techniques and analytical methods frequently used to measure sediment and asphaltenes onset for the adjustment of different process parameters in the refineries are spot test (ASTM-D-4740-95) total sediment (ASTM-4870-96) solubility parameters, optical microscope light scattering (PORLA) peptization value (P-value) ° colloidal instability index (CII) coking index. ... 

As an optical technique, Brillouin scattering allows the determination of the elastic constants and hence of the bulk moduli through the interaction of light with thermal excitation in a material, in particular acoustic phonons in a crystal. In this technique, the elastic constants Cn and Cgg can be directly obtained from measurement of the phase velocity of the longitudinal mode and of the shear horizontal mode traveling parallel to the crystal surface. The remaining constants,... 

The lifetime detection techniques are self-referenced in a sense that fluorescence decay is one of the characteristics of the emitter and of its environment and does not depend upon its concentration. Moreover, the results are not sensitive to optical parameters of the instrument, so that the attenuation of the signal in the optical path does not distort it. The light scattering produces also much lesser problems, since the scattered light decays on a very fast time scale and does not interfere with fluorescence decay observed at longer times. 

Light Scattering Technique. Properties of the light scattered by a large number of droplets can be used to determine droplet size distribution. Dobbins et al. 694 first derived the theoretical formulation of scattering properties of particles of arbitrary sizes and refractive indices in polydispersions of finite optical depth. Based on... 

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