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septicemia

(Encyclopedia)septicemia sĕptĭsēˈmēə [key], invasion of the bloodstream by virulent bacteria that multiply and discharge their toxic products. The disorder, which is serious and sometimes fatal, is commonly k...

condensation

(Encyclopedia)condensation, in physics, change of a substance from the gaseous (vapor) to the liquid state (see states of matter). Condensation is the reverse of vaporization, or change from liquid to gas. It can b...

Gil Robles, José María

(Encyclopedia)Gil Robles, José María hōsāˈ märēˈä hēl rōˈblās [key], 1898–1980, Spanish politician. In 1931, after the proclamation of the Second Republic, he became leader of the newly organized rig...

hardness

(Encyclopedia)hardness, property of matter commonly described as the resistance of a substance to being scratched by another substance. The degree of hardness is relative, different substances being compared with o...

Stirling engine

(Encyclopedia)Stirling engine, an external combustion reciprocating engine having an enclosed working fluid that is alternately compressed and expanded to operate a piston, thus converting heat from a variety of so...

physical chemistry

(Encyclopedia)physical chemistry, branch of science that combines the principles and methods of physics and chemistry. It provides a fundamental theoretical and experimental basis for all of chemistry, including or...

Weizman, Ezer

(Encyclopedia)Weizman, Ezer āˈzər vītˈsmän [key], 1924–2005, Israeli military officer and politician, president of Israel (1993–2000), b. Tel Aviv. A nephew of Chaim Weizmann, he helped found the Israeli ...

brake, in technology

(Encyclopedia)CE5 Shoe brake CE5 Disk brake brake, in technology, device to slow or stop the motion of a mechanism or vehicle. The vacuum brake system, or vacuum brake, depends upon the use of a vacuum to ...

norepinephrine

(Encyclopedia)norepinephrine nôrˌĕpīnĕfˈrən [key], a neurotransmitter in the catecholamine family that mediates chemical communication in the sympathetic nervous system, a branch of the autonomic nervous sys...

liquid air

(Encyclopedia)liquid air, ordinary air that has been liquefied by compression and cooling to extremely low temperatures (see liquefaction). Its commercial preparation involves purification by washing to remove solu...