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nuclear reactor

(Encyclopedia)CE5 Power reactor system nuclear reactor, device for producing controlled release of nuclear energy. Reactors can be used for research or for power production. A research reactor is designed to pr...

wool

(Encyclopedia)wool, fiber made from the fleece of the domestic sheep. In the United States, by the Wool Products Labeling Act of 1939, the term wool may be applied only to fabrics made entirely of new wool; t...

carbon

(Encyclopedia)CE5 The three solid forms of pure carbon: In the diamond crystal each carbon atom is surrounded symmetrically by four other carbons (at each of the four corners of a tetrahedron). In the graphite c...

coenzyme

(Encyclopedia)coenzyme kō-ĕnˈzīm [key], any one of a group of relatively small organic molecules required for the catalytic function of certain enzymes. A coenzyme may either be attached by covalent bonds to a ...

metal

(Encyclopedia)metal, chemical element displaying certain properties by which it is normally distinguished from a nonmetal, notably its metallic luster, the capacity to lose electrons and form a positive ion, and th...

sulfuric acid

(Encyclopedia)sulfuric acid, chemical compound, H2SO4, colorless, odorless, extremely corrosive, oily liquid. It is sometimes called oil of vitriol. Although sulfuric acid is now one of the most widely used c...

Arthropoda

(Encyclopedia)Arthropoda ärthrŏpˈədə [key] [Gr.,=jointed feet], largest and most diverse animal phylum. The arthropods include crustaceans, insects, centipedes, millipedes, spiders, scorpions, and the extinct ...

rubber

(Encyclopedia)CE5 Basic molecules in rubber rubber, any solid substance that upon vulcanization becomes elastic; the term includes natural rubber (caoutchouc) and synthetic rubber. The term elastomer is sometim...

vitamin

(Encyclopedia)vitamin, group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either t...

chemistry

(Encyclopedia)chemistry, branch of science concerned with the properties, composition, and structure of substances and the changes they undergo when they combine or react under specified conditions. Organic chemi...