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wood

(Encyclopedia)CE5 Wood A. Cross section of a woody stem B. Enlarged view, showing xylem, phloem, and cambium wood, botanically, the xylem tissue that forms the bulk of the stem of a woody plant. Xylem conducts ...

water supply

(Encyclopedia)water supply, process or activity by which water is provided for some use, e.g., to a home, factory, or business. The term may also refer to the supply of water provided in this way. In the United Sta...

neutron star

(Encyclopedia)neutron star, extremely small, extremely dense star, with as much as double the sun's mass but only a few miles in radius, in the final stage of stellar evolution. Astronomers Baade and Zwicky predict...

nitric oxide

(Encyclopedia)nitric oxide or nitrogen monoxide, a colorless gas formed by the combustion of nitrogen and oxygen as given by the reaction: energy + N2 + O2 → 2NO; m.p. −163.6℃; b.p. −151.8℃. Nitric oxide ...

nonmetal

(Encyclopedia)nonmetal, chemical element possessing certain properties by which it is distinguished from a metal. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and for...

National Forest System

(Encyclopedia)National Forest System, federally owned reserves, c.191 million acres (77.4 million hectares), administered by the Forest Service of the U.S. Dept. of Agriculture. The system is made up of 155 nationa...

Ledru-Rollin, Alexandre Auguste

(Encyclopedia)Ledru-Rollin, Alexandre Auguste älĕksäNˈdrə ôgüstˈ lədrüˈ-rôlăNˈ [key], 1807–74, French politician. A lawyer, he first became known as a radical opponent to the accession (1830) of Lou...

Ramaphosa, Cyril

(Encyclopedia)Ramaphosa, Cyril (Matamela Cyril Ramaphosa), 1952–, South African political leader, b. Johannesburg. A lawyer, he became involved in the antiapartheid Black Consciousness Movement while a university...

anxiety

(Encyclopedia)anxiety, anticipatory tension or vague dread persisting in the absence of a specific threat. In contrast to fear, which is a realistic reaction to actual danger, anxiety is generally related to an unc...

rhythm, biological

(Encyclopedia)rhythm, biological, or biorhythm, cyclic pattern of physiological changes or changes in activity in living organisms, most often synchronized with daily, monthly, or annual cyclical changes in the env...