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corundum

(Encyclopedia)corundum kərŭnˈdəm [key], mineral, aluminum oxide, Al2O3. The clear varieties are used as gems and the opaque as abrasive materials. Corundum occurs in crystals of the hexagonal system and in mass...

silver chloride

(Encyclopedia)silver chloride, chemical compound, AgCl, a white cubic crystalline solid. It is nearly insoluble in water but is soluble in a water solution of ammonia, potassium cyanide, or sodium thiosulfate (“h...

cinchona

(Encyclopedia)cinchona chĭngkōˈnə [key], name for species of the genus Cinchona, evergreen trees of the madder family native to the Andean highlands from Bolivia to Colombia and also to some mountainous regions...

apatite

(Encyclopedia)apatite ăpˈətīt [key], mineral, a phosphate of calcium containing chlorine or fluorine, or both, that is transparent to opaque in shades of green, brown, yellow, white, red, and purple. Apatite is...

indicators, acid-base

(Encyclopedia)indicators, acid-base, organic compounds that, in aqueous solution, exhibit color changes indicative of the acidity or basicity of the solution. Common indicators include p-nitrophenol, which is color...

mosquito

(Encyclopedia)mosquito məskēˈtō [key], small, long-legged insect of the order Diptera, the true flies. The females of most species have piercing and sucking mouth parts and apparently they must feed at least on...

leptospirosis

(Encyclopedia)leptospirosis lĕpˌtəspīrōˈsĭs [key], febrile disease caused by bacteria of the genus Leptospirae. The disease may affect dogs, cattle, pigs, sheep, goats, and horses and is also transmissible t...

sperm oil

(Encyclopedia)sperm oil, liquid wax obtained from the sperm whale, or cachalot, and related marine mammals. It flows readily, is clear, and varies in color from pale yellow to brownish yellow. Chemically it is not ...

encephalitis

(Encyclopedia)encephalitis ĕnsĕfˌəlīˈtəs [key], general term used to describe a diffuse inflammation of the brain and spinal cord, usually of viral origin, often transmitted by mosquitoes, in contrast to a b...

toxemia

(Encyclopedia)toxemia tŏksēˈmēə [key], disease state caused by the presence in the blood of bacterial toxins or other harmful substances. The effects of the bacterial toxins known as endotoxins are relatively ...