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cyclopropane

(Encyclopedia)cyclopropane, C3H6, a gaseous hydrocarbon. It is a cyclic alkane, its three carbon atoms being joined together in a ring. The angle between successive carbon-carbon bonds in the ring is only 60°, muc...

alanine

(Encyclopedia)CE5 alanine ălˈənēnˌ [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of proteins (see stereochemi...

chitin

(Encyclopedia)chitin kītˈən [key], main constituent of the shells of arthropods. Chitin, a polysaccharide (see carbohydrate) analogous in chemical structure to cellulose, consists of units of a glucose derivativ...

Moab

(Encyclopedia)Moab mōˈăb [key], ancient nation located in the uplands E of the Dead Sea, now part of Jordan. The area is unprotected from the east, hence its history is a chain of raids by the Bedouin. The Moabi...

arginine

(Encyclopedia)CE5 arginine ärˈjənĭn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of proteins. Its basic side ...

Martinelli, Ricardo

(Encyclopedia)Martinelli, Ricardo (Ricardo Alberto Martinelli Berrocal) 1952–, Panamanian business executive and political leader. The son of Italian immigrants, he became the head of a successful supermarket cha...

Bikini

(Encyclopedia)Bikini bēkēˈnē [key], atoll, c.2 sq mi (5.2 sq km), W central Pacific, one of the Ralik Chain, Marshall Islands. It comprises 36 islets on a reef 25 mi (40 km) long. After its inhabitants were rem...

surveying

(Encyclopedia)surveying, method of determining accurately points and lines of direction (bearings) on the earth's surface and preparing from them maps or plans. Boundaries, areas, elevations, construction lines, an...

aesthetics

(Encyclopedia)aesthetics ĕsthĕtˈĭks [key], the branch of philosophy that is concerned with the nature of art and the criteria of artistic judgment. The classical conception of art as the imitation of nature was...

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 ...