Light scattering sample geometry

In these sensors, the intrinsic absorption of the analyte is measured directly. No indicator chemistry is involved. Thus, it is more a kind of remote spectroscopy, except that the instrument comes to the sample (rather than the sample to the instrument or cuvette). Numerous geometries have been designed for plain fiber chemical sensors, all kinds of spectroscopies (from IR to mid-IR and visible to the UV from Raman to light scatter, and from fluorescence and phosphorescence intensity to the respective decay times) have been exploited, and more sophisticated methods including evanescent wave spectroscopy and surface plasmon resonance have been applied. 

Small-angle light scattering has also been extensively applied to PLCs subject to flow [173]. As in the case of scattering dichroism, SALS patterns arise principally from fluctuations in orientation, and these arc strongest in the vicinity of disclinations, or defects in the director field. The experimental geometries used for SALS in liquid crystals normally use polarizers placed before and after the sample. The arrangements include VV scatter-... 

The correction of absorption depends on the geometry of the cell and the scattering volume. Different relationships have been proposed to correct the Rayleigh factor measured with conventional goniometers, in which the detector rotates around the sample m a horizontal plane (Brice et al. 1953, Forss et al. 1967, Pla et al. 1977). With LALLS (low angle laser light scattering) pho-... 

Light-scattering spectroscopy proved to be a more sensitive method than tur-bidimetry and pNMR. In this method, the intensity of scattered light, rather than the attenuation of the signal intensity (/// ) is measured. The particular geometry of the sample cell and positioning of the detectors also maximize the collection of the scattered light. This technique proved to be very convenient, user-friendly, and reproducible. 

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