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Lee, Light-Horse Harry
(Encyclopedia)Lee, Light-Horse Harry: see Lee, Henry. ...Nature Conservancy
(Encyclopedia)Nature Conservancy, nonprofit organization established in 1951 to preserve or aid in the preservation of natural environments. It protects wilderness areas in the United States and Canada and is affil...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...photon
(Encyclopedia)photon fōˈtŏn [key], the particle composing light and other forms of electromagnetic radiation, sometimes called light quantum. The photon has no charge and no mass. About the beginning of the 20th...Stokes, Sir George Gabriel
(Encyclopedia)Stokes, Sir George Gabriel, 1819–1903, British mathematician and physicist, b. Ireland, studied at Cambridge. From 1849 he was a professor of mathematics at Cambridge; he served as secretary (1854...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 ...zinc oxide
(Encyclopedia)zinc oxide, chemical compound, ZnO, that is nearly insoluble in water but soluble in acids or alkalies. It occurs as white hexagonal crystals or a white powder commonly known as zinc white. Zinc white...ether, in physics and astronomy
(Encyclopedia)ether or aether, in physics and astronomy, a hypothetical medium for transmitting light and heat (radiation), filling all unoccupied space; it is also called luminiferous ether. In Newtonian physics a...International Union for the Conservation of Nature and Natural Resources
(Encyclopedia)International Union for the Conservation of Nature and Natural Resources (IUCN), formerly World Conservation Union, international organization founded in 1948 to encourage the preservation of wildlife...Worldwide Fund for Nature
(Encyclopedia)Worldwide Fund for Nature: see World Wildlife Fund. ...Browse by Subject
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