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Grignard reagent

(Encyclopedia)Grignard reagent grēnyärdˈ rēāˈjənt [key], any of an important class of extremely reactive chemical compounds used in the synthesis of hydrocarbons, alcohols, carboxylic acids, and other compou...

Tsien, Roger Yonchien

(Encyclopedia)Tsien, Roger Yonchien, 1952–2016, American biochemist, b. New York City, Ph.D. Cambridge, 1977. Tsien was a researcher at Cambridge (1977–81) and a professor at the Univ. of California, Berkeley (...

Orbiting Geophysical Observatory

(Encyclopedia)Orbiting Geophysical Observatory (OGO), series of six orbiting observatories (see observatory, orbiting) launched between 1964 and 1969 by the National Aeronautics and Space Administration (NASA) to s...

hydrolysis

(Encyclopedia)hydrolysis hīdrŏlˈĭsĭs [key], chemical reaction of a compound with water, usually resulting in the formation of one or more new compounds. The most common hydrolysis occurs when a salt of a weak ...

hysteresis

(Encyclopedia)hysteresis hĭsˌtərēˈsĭs [key], phenomenon in which the response of a physical system to an external influence depends not only on the present magnitude of that influence but also on the previous...

field, in physics

(Encyclopedia)field, in physics, region throughout which a force may be exerted; examples are the gravitational, electric, and magnetic fields that surround, respectively, masses, electric charges, and magnets. The...

term limits

(Encyclopedia)term limits, statutory limitations placed on the number of terms officeholders may serve. Focusing especially on members of the U.S. Congress, term limits became an important national political issue ...

waters, territorial

(Encyclopedia)waters, territorial, all waters within the jurisdiction, recognized in international law, of a country. Certain waters by their situation are controlled by one nation; these include wholly enclosed in...

spintronics

(Encyclopedia)spintronics, spin electronics, or magnetoelectronics, science and technology that harnesses the spin state of electrons in addition to the electrical charge state to store data or perform calculation...

euthanasia

(Encyclopedia)euthanasia yo͞oˌthənāˈzhə [key], either painlessly putting to death or failing to prevent death from natural causes in cases of terminal illness or irreversible coma. The term comes from the Gre...