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chemical bond

(Encyclopedia)chemical bond, mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the for...

honey locust

(Encyclopedia)honey locust, leguminous deciduous tree (Gleditsia triacanthos) of the family Leguminosae (pulse family), native to the eastern half of the United States but planted as a shade tree in many regions of...

Chauvin, Yves

(Encyclopedia)Chauvin, Yves, 1930–2015, French chemist, b. Menen, Belgium, grad. Lyon School of Chemistry, Physics, and Electronics (CPE), 1954. Chauvin was a research engineer (1960–91) and then research direc...

Integrated Pest Management

(Encyclopedia)Integrated Pest Management (IPM), planned program that coordinates economically and environmentally acceptable methods of pest control with the judicious and minimal use of toxic pesticides. IPM progr...

mercaptan

(Encyclopedia)mercaptan thīˈōl [key], any of a class of organic compounds containing the group –SH bonded to a carbon atom. The volatile low-molecular-weight mercaptans have disagreeable odors. Mercaptans are ...

Arp, Jean

(Encyclopedia)Arp, Jean or Hans, 1887–1966, French sculptor and painter. Arp was connected with the Blaue Reiter in Munich, various avant-garde groups in Paris, including the surrealists, and the Dadaists in Zür...

Suzuki, Akira

(Encyclopedia)Suzuki, Akira, 1930–, Japanese chemist, Ph.D. Hokkaido Univ., Sapporo, 1959. He was a professor at Hokkaido from 1963 until his retirement in 1994. Since then, he has taught for short periods at Oka...

purine

(Encyclopedia)CE5 Purines found in deoxyribonucleic acid (DNA) purine, type of organic base found in the nucleotides and nucleic acids of plant and animal tissue. The German chemist Emil Fischer did much of the...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

protozoan

(Encyclopedia)protozoan prōˌtəzōˈən [key], informal term for the unicellular heterotrophs of the kingdom Protista. Protozoans comprise a large, diverse assortment of microscopic or near-microscopic organisms ...