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sanitary science

(Encyclopedia)sanitary science, principles of health preservation, embracing hygiene, on an individual level, and public health, on a communal level. Those who specialize in sanitary science are sanitary engineers....

equivalent weight

(Encyclopedia)equivalent weight. The equivalent weight of an element or radical is equal to its atomic weight or formula weight divided by the valence it assumes in compounds. The unit of equivalent weight is the a...

Jordan, river, Asia

(Encyclopedia)Jordan, river, c.200 mi (320 km) long, formed in the Hula basin, N Israel, by the confluence of three headwater streams and meandering S through the Sea of Galilee to the Dead Sea; the region of Pales...

mortar, in building

(Encyclopedia)mortar, in building, mixture of lime or cement with sand and water, used as a bedding and adhesive between adjacent pieces of stone, brick, or other material in masonry construction. Lime mortar, a co...

nitric acid

(Encyclopedia)nitric acid, chemical compound, HNO3, colorless, highly corrosive, poisonous liquid that gives off choking red or yellow fumes in moist air. It is miscible with water in all proportions. It forms an a...

lipids

(Encyclopedia)lipids, a broad class of organic products found in living systems. Most are insoluble in water but soluble in nonpolar solvents. The definition excludes the mineral oils and other petroleum products o...

landslide

(Encyclopedia)landslide, rapid slipping of a mass of earth or rock from a higher elevation to a lower level under the influence of gravity and water lubrication. More specifically, rockslides are the rapid downhill...

tenrec

(Encyclopedia)tenrec tĕnˈrĕk [key], any of the small insectivorous mammals of the family Tenrecidae, also called tendrecs or tanrecs. These animals are found on the island of Madagascar. In that closed environme...

blue whale

(Encyclopedia)blue whale, a baleen whale, Balaenoptera musculus. Also called the sulphur-bottom whale and Sibbald's rorqual, it is the largest animal that has ever lived. Blue whales have been known to reach a leng...

river

(Encyclopedia)river, stream of water larger than a brook or creek. Land surfaces are never perfectly flat, and as a result the runoff after precipitation tends to flow downward by the shortest and steepest course i...