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Gobi

(Encyclopedia)Gobi gōˈbē [key], Mandarin Yintai shamo, great stony desert of N central Asia, c.500,000 sq mi (1,295,000 sq km), extending c.1,000 mi (1,610 km) from east to west across SE Mongolia and N China fr...

denaturation

(Encyclopedia)denaturation, term used to describe the loss of native, higher-order structure of protein molecules in solution. Most globular proteins exhibit complicated three-dimensional folding described as secon...

drought

(Encyclopedia)drought, abnormally long period of insufficient rainfall. Drought cannot be defined in terms of inches of rainfall or number of days without rain, since it is determined by such variable factors as th...

convection

(Encyclopedia)convection, mode of heat transfer in fluids (liquids and gases). Convection depends on the fact that, in general, fluids expand when heated and thus undergo a decrease in density (since a given volume...

tundra

(Encyclopedia)tundra tŭnˈdrə [key], treeless plains of N North America and N Eurasia, lying principally along the Arctic Circle, on the coasts and islands of the Arctic Ocean, and to the north of the coniferous ...

rainmaking

(Encyclopedia)rainmaking, production of rain by artificial means now generally disregarded, though it is probable that rainmaking hastens or increases rainfall from clouds suitable for natural rainfall. Interest in...

Lynen, Feodor

(Encyclopedia)Lynen, Feodor fāōˈdôr lēˈnən [key], 1911–79, German biochemist, grad. Univ. of Munich (Ph.D. 1937). He began teaching at the Max Planck Institute for Cell Chemistry in Munich in 1947. His res...

mechanism

(Encyclopedia)mechanism, philosophical theory about the nature of organic systems, holding that organisms are machines in the sense that they are material systems. Mechanism seeks to explain biological processes, i...

I

(Encyclopedia)I, 9th letter of the alphabet. This vowel can be pronounced with a short vowel sound, as the ĭ in sit, or with a long vowel sound, like the ī in ride. The Greek correspondent is iota. J is a formal ...

Ekimov, Alexei

(Encyclopedia)Alexei Ekimov, 1945– , b. Leningrad, USSR, Russian physicist, studied at Leningrad State University and Ioffe Institute of the Russian Academy of Scie...