Colored lights

Color and Color Separation. In 1860,James Clerk MaxweU discovered that all visible colors could be matched by appropriate combinations of three primary colors, red, green, and blue (RGB). His experiment involved mixtures of colored lights added together to produce other colors or white light. This additive color is weU represented by the primaries RGB. Indeed, human color vision is trichromatic, ie, human visual response approximates receptors for the colors recognized as red, green, and blue (see Color). 

Zinc compounds are generally colorless unless the other component, eg, chromate, is colored. The lack of color of most zinc compounds in visible light is a great advantage in that they do not color paint films, plastics, mbber, cosmetics, etc. However, when excited by various types of radiation and at various temperatures, zinc oxide, sulfide, selenide [1315-09-9], and related compounds exhibit luminescence, ie, they emit colored light (see Luminescent materials). Zinc-based phosphors can be produced in many colors, depending upon the added dopants. They are used in television tubes, luminescent glasses, and various specialty products. 

Difference in optical properties can be used as the basis to separate solids in a mixture. Optic properties include color, light reflectance, opacity, and fluorescence excited by ultraviolet rays or x-rays. Differences in elec trical conductance can also be used for separation. With appropriate sensing, the particles in a moving stream can be sorted by using an air jet or other means to deflect certain particles away from the mainstream (Fig. 19-10). The lower limit of particle size is about... 

Observable Characteristics - Physical State (as normally shipped) Solid Color. Light straw to colorless Odor Slight acid. 

Chemical Designations - Synonyms Fuel Oil 1-D Fuel Oil 2-D Chemical Formula Not applicable. Observable Characteristics - Sltate (asshipped) Liquid Color Light brown Odor Like fuel... 

Observable Characteristics-P/rysicn/Simre (as normally shipped) Liquid Color. Light straw amber Odor Ammoniacal. 

Irrung./. error, mistake disagreement, isabellen. -farbig, isabellfarbig, a. cream-colored, light buflf. 

Fig. 8.8 The structures of compounds 37 (carbons colored light green), 38 (carbons colored green) and 39 (carbons colored dark green) bound to PTPl B. The two rings are orthogonal to each other. This is energetically...

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