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morphine

(Encyclopedia)morphine, principal derivative of opium, which is the juice in the unripe seed pods of the opium poppy, Papaver somniferum. It was first isolated from opium in 1803 by the German pharmacist F. W. A. S...

ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

magnetic resonance

(Encyclopedia)magnetic resonance, in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then a...

binary star

(Encyclopedia)CE5 A. Eclipsing binary: Primary component passing behind secondary (dimmer) component B. Light curve for eclipsing binary binary star or binary system, pair of stars that are held together by the...

Chulalongkorn

(Encyclopedia)Chulalongkorn räˈmä [key], 1853–1910, king of Siam (1868–1910). Educated in part by a British governess, Anna Leonowens, and an English tutor, he greatly advanced the Westernization of Siam (pr...

Chun Doo-hwan

(Encyclopedia)Chun Doo Hwan jûn dō hwän [key], 1931–2021, Korean military leader, president of South Korea ...

anticoagulant

(Encyclopedia)anticoagulant ănˌtēkōăgˈyələnt [key], any of several substances that inhibit blood clot formation (see blood clotting). Some anticoagulants, such as the coumarin derivatives bishydroxycoumarin...

Hobbema, Meindert

(Encyclopedia)Hobbema, Meindert mīnˈdərt hôbˈəmä [key], 1638–1709, Dutch landscape painter. In landscape art Hobbema was second only to his contemporary Jacob van Ruisdael, with whom he may have studied. M...

Halifax, Charles Montagu, earl of

(Encyclopedia)Halifax, Charles Montagu, earl of hălˈəfăks [key], 1661–1715, English statesman. He and Matthew Prior were coauthors of a parody of John Dryden's The Hind and the Panther, entitled The Town and ...

Mi'kmaq

(Encyclopedia)Mi'kmaq or Micmac, Native North Americans whose language belongs to the Algonquian branch of the Algonquian-Wakashan linguistic stock (see Native American languages). They inhabit Nova Scotia, Cape Br...