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photochemistry
(Encyclopedia)photochemistry, study of chemical processes that are accompanied by or catalyzed by the emission or absorption of visible light or ultraviolet radiation. A molecule in its ground (unexcited) state can...bioluminescence
(Encyclopedia)bioluminescence bīˌōlo͞oˌmĭnĕsˈəns [key], production of light by living organisms. Organisms that are bioluminescent include certain fungi and bacteria that emit light continuously. The dinof...electron-volt
(Encyclopedia)electron-volt, abbr. eV, unit of energy used in atomic and nuclear physics; 1 electron-volt is the energy transferred in moving a unit charge, positive or negative and equal to that charge on the elec...snowshoes
(Encyclopedia)snowshoes, footgear enabling the wearer to walk on soft snow without sinking. A snowshoe consists of a light frame of tough wood or aluminum, roughly the shape of a large tennis racket, which is strun...Lee, Light-Horse Harry
(Encyclopedia)Lee, Light-Horse Harry: see Lee, Henry. ...optics
(Encyclopedia)optics, scientific study of light. Physical optics is concerned with the genesis, nature, and properties of light; physiological optics with the part light plays in vision; and geometrical optics with...Raman effect
(Encyclopedia)Raman effect räˈmən [key], appearance of additional lines in the spectrum of monochromatic light that has been scattered by a transparent material medium. The effect was discovered by C. V. Raman i...bicycle
(Encyclopedia)bicycle, light, two-wheeled vehicle driven by pedals. The name velocipede is often given to early forms of the bicycle and to its predecessor, the dandy horse, a two-wheeled vehicle moved by the thrus...airglow
(Encyclopedia)airglow, faint diffuse illumination of the sky originating in the upper atmosphere. Although it occurs at all times of day throughout the upper atmosphere, it is most typically visible to an observer ...fluorescence
(Encyclopedia)fluorescence flo͝orĕsˈəns [key], luminescence in which light of a visible color is emitted from a substance under stimulation or excitation by light or other forms of electromagnetic radiation or ...Browse by Subject
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