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amino group

(Encyclopedia)amino group, in chemistry, functional group that consists of a nitrogen atom attached by single bonds to hydrogen atoms, alkyl groups, aryl groups, or a combination of these three. An organic compound...

berkelium

(Encyclopedia)berkelium bûrˈklēəm [key] [from Berkeley], artificially produced radioactive chemical element; symbol Bk; at. no. 97; mass no. of most stable isotope 247; m.p. about 1,050℃; b.p. about 2,590℃;...

lake, body of water

(Encyclopedia)lake, inland body of standing water occupying a hollow in the earth's surface. The study of lakes and other freshwater basins is known as limnology. Lakes are of particular importance since they act a...

recycling

(Encyclopedia)recycling, the process of recovering and reusing waste products—from household use, manufacturing, agriculture, and business—and thereby reducing their burden on the environment. During World War ...

radar

(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...

El Niño–Southern Oscillation

(Encyclopedia)El Niño–Southern Oscillation (ENSO) ĕl nēnˈyō [key], large-scale climatic fluctuation of the tropical Pacific Ocean and the overlying atmosphere. The El Niño [Span.,=the child] is the South Am...

hurricane

(Encyclopedia)CE5 View into the eye of a hurricane showing the structure of the surrounding cloud wall hurricane, tropical cyclone in which winds attain speeds greater than 74 mi (119 km) per hr. Wind speeds gu...

seaborgium

(Encyclopedia)seaborgium sēbôrˈgēəm [key], artificially produced radioactive chemical element; symbol Sg; at. no. 106; mass number of most stable isotope 271; m.p., b.p., sp. gr., and valence unknown. Situated...

fermentation

(Encyclopedia)fermentation, process by which the living cell is able to obtain energy through the breakdown of glucose and other simple sugar molecules without requiring oxygen. Fermentation is achieved by somewhat...

moscovium

(Encyclopedia)moscovium mŏskōˈvēəm [key], artificially produced radioactive chemical element; symbol Mc; at. no. 115; mass number of most stable isotope 288; m.p., b.p., sp. gr., and valence unknown. Situated ...