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Heimlich maneuver

(Encyclopedia)Heimlich maneuver, emergency procedure used to treat choking victims whose airway is obstructed by food or another substance. It forces air from the lungs through the windpipe, pushing the obstruction...

blister beetle

(Encyclopedia)blister beetle, common name for certain soft-bodied, usually black or brown, mostly elongate and cylindrical beetles belonging to the family Meloidae. Blister beetles are common insects found feeding ...

sand

(Encyclopedia)sand, rock material occurring in the form of loose, rounded or angular grains, varying in size from .06 mm to 2 mm in diameter, the particles being smaller than those of gravel and larger than those o...

sphalerite

(Encyclopedia)sphalerite sfălˈərīt, sfāˈ– [key], mineral composed of zinc sulfide, usually containing some iron and a little cadmium. It occurs in crystals of the isometric system but more generally in clea...

barite

(Encyclopedia)barite bərīˈtēz [key] [New Lat., from barium], or heavy spar, a white, yellow, blue, red, or colorless mineral. It is a sulfate of barium, BaSO4, found in nature as tabular crystals or in granular...

coltsfoot

(Encyclopedia)coltsfoot, Eurasian perennial herb (Tussilago farfara) of the family Asteraceae (aster family), now a widespread weed in most northern lands. The scaly flower stalk bears a yellow flower head and down...

oxalic acid

(Encyclopedia)oxalic acid ĕthˌāndīōĭk [key], HO2CCO2H, a colorless, crystalline organic carboxylic acid that melts at 189℃ with sublimation. Oxalic acid and oxalate salts are poisonous. Oxalic acid is found...

acetone

(Encyclopedia)acetone prōˈpənōn [key], CH3COCH3, colorless, flammable liquid. Acetone melts at −94.8℃ and boils at 56.2℃. It is the simplest aliphatic ketone. Acetone is widely used in industry as a solve...

Carothers, Wallace Hume

(Encyclopedia)Carothers, Wallace Hume kərŭᵺˈərz [key], 1896–1937, American chemist, b. Burlington, Iowa. He received his doctorate at the Univ. of Illinois in 1924, then taught organic chemistry there and a...

bitumen

(Encyclopedia)bitumen bĭtyo͞oˈmən [key] a generic term referring to flammable, brown or black mixtures of tarlike hydrocarbons, derived naturally or by distillation from petroleum. It can be in the form of a vi...