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hydrate

(Encyclopedia)hydrate hīˈdrāt [key], chemical compound that contains water. A common hydrate is the familiar blue vitriol, a crystalline form of cupric sulfate. Chemically, it is cupric sulfate pentahydrate, CuS...

cautery

(Encyclopedia)cautery, searing or destruction of living animal tissue by use of heat or caustic chemicals. In the past, cauterization of open wounds, even those following amputation of a limb, was performed with ho...

assaying

(Encyclopedia)assaying əsāˈyĭng, ăsˈāyĭng [key], in metallurgy, process of determining the specific metallic content of an ore, alloy, or other substance, especially one containing precious metals. It consi...

hashish

(Encyclopedia)hashish hăshˈēsh, –ĭsh [key], resin extracted from the flower clusters and top leaves of the hemp plant, Cannabis sativa, and C. indica. Hashish, called charas in India, is the most potent grade...

cover crop

(Encyclopedia)cover crop, green temporary crop grown to prevent or reduce erosion and to improve the soil by building up its organic content. Green-manure crops, which are specifically grown for their organic conte...

explosive

(Encyclopedia)explosive, substance that undergoes decomposition or combustion with great rapidity, evolving much heat and producing a large volume of gas. The reaction products fill a much greater volume than that ...

gastric juice

(Encyclopedia)gastric juice, thin, strongly acidic (pH varying from 1 to 3), almost colorless liquid secreted by the glands in the lining of the stomach. Its essential constituents are the digestive enzymes pepsin ...

antifreeze

(Encyclopedia)antifreeze, substance added to a solvent to lower its freezing point. The solution formed is called an antifreeze mixture. Antifreeze is typically added to water in the cooling system of an internal-c...

stratification

(Encyclopedia)stratification (Lat.,=made in layers), layered structure formed by the deposition of sedimentary rocks. Changes between strata are interpreted as the result of fluctuations in the intensity and persis...

Ratnapura

(Encyclopedia)Ratnapura rŭtˈnəpo͝orə [key] [Sinhalese,=city of gems], town (1995 est. pop. 46,000), SW Sri Lanka. Located in a rubber- and rice-producing area, Ratnapura is Sri Lanka's major precious-stone cen...