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detergent

(Encyclopedia)detergent dētûrˈjənt, dĭ– [key], substance that aids in the removal of dirt. Detergents act mainly on the oily films that trap dirt particles. The detergent molecules have a hydrocarbon portion...

allergy

(Encyclopedia)allergy, hypersensitive reaction of the body tissues of certain individuals to certain substances that, in similar amounts and circumstances, are innocuous to other persons. Allergens, or allergy-caus...

gadolinium

(Encyclopedia)gadolinium gădəlĭnˈēəm [key], metallic chemical element; symbol Gd; at. no. 64; at. wt. 157.25; m.p. 1,312℃; b.p. 3,233℃; sp. gr. 7.898 at 25℃; valence +3. Gadolinium is a malleable, ducti...

Rasputin, Grigori Yefimovich

(Encyclopedia)Rasputin, Grigori Yefimovich răspyo͞oˈtĭn, Rus. grĭgôˈrē yĭfēˈməvĭch rəspo͞oˈtyĭn [key], 1869–1916, Russian holy man and courtier, a notorious figure at the court of Czar Nicholas I...

selenium

(Encyclopedia)selenium səlēˈnēəm [key], nonmetallic chemical element; symbol Se; at. no. 34; at. wt. 78.96; m.p. 217℃; b.p. about 685℃; sp. gr. 4.81 at 20℃; valence −2, +4, or +6. Selenium is directly ...

Goering, Hermann Wilhelm

(Encyclopedia)Goering or Göring, Hermann Wilhelm both: hĕrˈmän vĭlˈhĕlm göˈrĭng [key], 1893–1946, German National Socialist leader. In World War I he was a hero of the German air force. An early member ...

Demosthenes

(Encyclopedia)Demosthenes dĭmŏsˈthənēz [key], 384?–322 b.c., Greek orator, generally considered the greatest of the Greek orators. He was a pupil of Isaeus, and—although the story of his putting pebbles in...

Himmler, Heinrich

(Encyclopedia)Himmler, Heinrich hīnˈrĭkh hĭmˈlər [key], 1900–1945, German Nazi leader. An early member of the National Socialist German Workers' (Nazi) party, Himmler took part in Adolf Hitler's “beer-hal...

barium

(Encyclopedia)barium bârˈēəm [key] [Gr.,=heavy], metallic chemical element; symbol Ba; at. no. 56; at. wt. 137.327; m.p. 725℃; b.p. 1,640℃; sp. gr. 3.5 at 20℃; valence +2. Barium is a soft, silver-white, ...

ring, piece of jewelry

(Encyclopedia)ring, small ornamental hoop usually worn on finger or thumb, but it may be attached to the ear or the nose. Finger rings made of bronze, gold, and silver from the period c.2600–1500 b.c. have been f...