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Red River, rivers, United States and Canada

(Encyclopedia)Red River. 1 River, 1,222 mi (1,967 km) long, southernmost of the large tributaries of the Mississippi River. It rises in two branches in the Texas Panhandle and flows SE between Texas and Oklahoma an...

acids and bases

(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...

coronavirus

(Encyclopedia)coronavirus, any of a group (family Coronaviridae, subfamily Orthocoronavirinae) of enveloped single-stranded RNA viruses that have a crownlike or sunlike appearance under an electron microscope due t...

jelly and jam

(Encyclopedia)jelly and jam, gelatinous, sweet food prepared by preserving fresh fruits. Since most fresh fruits contain about 80% water and from 10% to 15% sugar, they are subject to fermentation. They may be pres...

adhesion and cohesion

(Encyclopedia)adhesion and cohesion, attractive forces between material bodies. A distinction is usually made between an adhesive force, which acts to hold two separate bodies together (or to stick one body to anot...

Antigua and Barbuda

(Encyclopedia)CE5 Antigua and Barbuda ăntēˈgə, –gwə, bärbo͞oˈdə, –byo͞oˈ– [key], independent Commonwealth nation (2020 est. pop. 97,928), 171 sq mi (442 sq km), We...

Baghdadi, Abu Bakr al-

(Encyclopedia)Baghdadi, Abu Bakr al-, nom de guerre of Awwad Ibrahim Ali al-Badri al-Samarrai, 1971–2019, Iraqi jihadist leader. Following the U.S. invasion of Iraq in 2003, he helped found a Sunni militia. Arres...

DDT

(Encyclopedia)DDT or 2,2-bis(p-chlorophenyl)-1,1,1,-trichloroethane, chlorinated hydrocarbon compound used as an insecticide. First introduced during the 1940s, it killed insects that spread disease and fed on crop...

fungicide

(Encyclopedia)fungicide fŭnˈjəsīdˌ, fŭngˈgə– [key], any substance used to destroy fungi. Some fungi are extremely damaging to crops (see diseases of plants), and others cause diseases in humans and other ...

American Association for the Advancement of Science

(Encyclopedia)American Association for the Advancement of Science (AAAS), private organization devoted to furthering the work of scientists and improving the effectiveness of science in the promotion of human welfa...