Color-emissive reflective

Color reactions and optical measurements are among the most versatile tools in biochemical analysis. The correlations between structure or energy states of organic compounds and electromagnetic radiation are well established, and qualitative and quantitative information can be obtained from measurements of adsorption, emission, reflection, flurorescence, and luminescence, the wavelength ranges of UV, visible, and IR radiation. 

All the analytical methods mentioned to separate, identify, and quantify chlorophylls and derivatives consume time, money, and samples. As alternatives, industries have been employing non-destructive methods for surface color measurements that are not only indirectly related to chlorophyll content, but may also estimate the pigments directly in tissues, leaving the sample intact and enabling serial analyses in a relatively short time. Eood color affects consumer acceptance and is an important criterion for quality control. Color vision is a complex phenomenon that depends on both the total content and number of pigments and also on absorption, reflectance and emission spectra of each compound present. 

Color—the selective absorption, emission, or reflection of components of the visible spectrum—can be produced by a variety of mechanisms. We already noted that water... 

Figure 25. A femtosecond TRPES scheme for studying NO dimer photodissociation. A UV pump pulse creates the excited state (NO)j. Its subsequent evolution is monitored all the way from initial excitation to final product emission via a UV probe pulse, projecting the wave packet onto the ionization continuum The resulting photoelectron spectrum, reflecting vibrational and electronic changes during dissociation, is depicted in green. See color insert.

It has been known for some time that the color of fabrics and the types of dyes used can be important factors in determining the solar reflectance of fabrics (15., l6). However, color of fabrics in apparel has no effect on the loss of body heat since the color of a fabric has a small effect on its surface emittance (16). Other factors such as fiber orientation and length, yarn twist, and fabric structure also influence the infrared and visible reflection properties of various fabrics (17). In a recent study, the various radiant properties of textiles measured at the peak emission wavelength of sunlight (0.6 urn), were found to approach constant values of absorptivity (0.67), absorptance (0.33), transmissivity (0.0), and reflectivity (0.33) at infinite superficial density (3.) ... 

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