Light technique

The cameras are usually used in two different modes, front light and backlight. Standard images using the front light technique are very useful in tracking particle movements, collisions, breakup, and coalescence (Figure 15.2). 

On this basis of petrographic data from both transmitted and reflected light techniques, the seams can be classified into three units in the case of Seam 4 and four units in the case of Seam 2. These are ... 

The resemblance of the photocurrent to the optical adsorption spectrum has suggested the involvement of molecular excited states in the creation of charge carriers. While this resemblance is by no means universally observed, the concept of carrier creation via exciton interactions at or very near the illuminated electrode has become increasingly favored. Many of the data leading to these conclusions have been obtained by the use of pulsed light techniques (6, 7,3). These methods are virtually independent of electrode effects and the subsequent analysis of the transient current has led to considerable advances in the theory of charge transfer in molecular crystals. 

More recent light-scattering studies (ref. 26,59,60) of microbubble populations in fresh water, using laser-light sources, have yielded very similar results. For example, Keller s laser-scattered-light technique (ref. 26) provided precise measurements of the size and number of freestream gas nuclei (i.e., long-lived microbubbles) in a cavitation tunnel from microbubble spectra... 

A second class of polarizers uses dichroism to produce linearly polarized light. Techniques to produce dichroic polarizing sheets were pioneered by Land [52], These are made by dissolving a strongly dichroic, small molecule into an amorphous, transparent polymer. The dichroic molecules are then oriented by a uniaxial stretching of the polymer matrix. Since this is accomplished below the polymers glass transition temperature, this ori-... 

The transmitted-light technique is limited by the opaque nature of most oil samples and, in cases where the sample cannot be made thin enough, an alternative technique using reflected light is available. 

Strain gages have to be bonded to areas of machine parts that are most sensitive to applied force. Such areas can be identified with the use of polarized light technique that points out the stress distribution. 

Care must be taken to ensure the slide is properly prepared to accept the continuous phase. Water-wet solids suspended in an oil phase can interact differently when prepared on a hydrophilic glass surface compared with a hydrophobic sample holder. Careful observation and comparison of suspension morphology using both hydrophilic and oleophilic sample holders are sometimes required to confidently characterize a suspension. The transmitted light technique is limited by the opaque nature of most oil samples, and in cases where the sample cannot be made thin enough, an alternative technique using reflected light is available. 

A choice between reflected-light or transmitted-light techniques for plant use may, of necessity, be made on the basis of personal ease of application, tradition, equipment availability, or other reasons. In the writer s opinion, a combination of the two modes of analysis is best. Reflected-light observations of polished sections of whole or crushed clinkers from the... 

Long, G.R., "Clinker Quality Characterization by Reflected Light Techniques," Proceedings of the Fourth International Conference on Cement Microscopy,International Cement Microscopy Association, Las Vegas, Nevada, 1982a, pp. 92-109. 

The lOSA theory for reactive photodissociation described above, together with the Kulander-Light technique for calculating photodissociation integrals, has been incorporated into a general computer program for symmetric triatomic molecules. The program can be used for various mass combinations. For example, calculations of the 3D photoabsorption spectrum for... 

The scattered light techniques determine cither Rayleigh s ratio (with nephelome-ters) (Fabelinski, 1965 Eskin, 1973) or turbidity t (with colorimeters and spectrophotometers). The former quantity... 

Ffe. 12.10 Different light patterns used in structured-light techniques [3]... 

Singh, G.D., Narasimhan, M.D., 1975. Study of ceramic microstructures with reflected light technique. Indian Ceram. 18, 239. 

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