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entropy

(Encyclopedia)entropy ĕnˈtrəpē [key], quantity specifying the amount of disorder or randomness in a system bearing energy or information. Originally defined in thermodynamics in terms of heat and temperature, e...

propeller

(Encyclopedia)propeller, device consisting of a hub with one or more blades that propels a craft to which it is attached by rotating its blades in a fluid such as air or water. In the latter part of the 1830s the S...

sonar

(Encyclopedia)sonar sōˈnär [key], device used underwater for locating submerged objects and for submarine communication by means of sound waves. The term sonar is an acronym for sound navigation ranging. The mai...

sugarcane

(Encyclopedia)sugarcane, tall tropical perennials (species of Saccharum, chiefly S. officinarum) of the family Poaceae (grass family), probably cultivated in their native Asia from prehistoric times. Sugarcane some...

buttress

(Encyclopedia)CE5 Types of buttresses buttress, mass of masonry built against a wall to strengthen it. It is especially necessary when a vault or an arch places a heavy load or thrust on one part of a wall. In t...

rain

(Encyclopedia)rain, precipitation in liquid form. It consists of drops of water falling from clouds; if the drops are very small, they are collectively termed drizzle. Rain plays a key role in the hydrologic, or wa...

Jiangxi

(Encyclopedia)Jiangxi kyăngˈsēˈ, jyängˈ– [key], province (2010 pop. 44,567,475), c.66,000 sq mi (170,940 sq km), SE China. Nanchang is the capital. The largely hilly and mountainous surface is drained by ma...

Know-Nothing movement

(Encyclopedia)Know-Nothing movement, in U.S. history. The increasing rate of immigration in the 1840s encouraged nativism. In Eastern cities where Roman Catholic immigrants especially had concentrated and were welc...

Rh factor

(Encyclopedia)Rh factor, protein substance present in the red blood cells of most people, capable of inducing intense antigenic reactions. The Rh, or rhesus, factor was discovered in 1940 by K. Landsteiner and A. S...

walrus

(Encyclopedia)walrus, marine mammal, Odobenus rosmarus, found in Arctic seas. Largest of the fin-footed mammals, or pinnipeds (see seal), the walrus is also distinguished by its long tusks and by cheek pads bearing...