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aerogel

(Encyclopedia)aerogel, any of a group of extremely light and porous solid materials; the lightest is less than four times as dense as dry air. Aerogels are produced from certain gels (see colloid) by heating the ge...

urinary system

(Encyclopedia)CE5 Urinary system urinary system, group of organs of the body concerned with excretion of urine, that is, water and the waste products of metabolism. In humans, the kidneys are two small organs s...

liquid

(Encyclopedia)liquid, one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from solid and gas, in which a substance has a definite volume but no definite shape. T...

fluid

(Encyclopedia)fluid, any substance that is able to flow. Of the four states of matter, only a solid is not a fluid, since it has a definite shape that is not readily changed. Any liquid, gas, or plasma is classed a...

wedge

(Encyclopedia)wedge, piece of wood or metal thick at one end and sloping to a thin edge at the other; an application of the inclined plane. It is employed in separating two objects from each other or in separating ...

aquaponics

(Encyclopedia)aquaponics, the growing of plants and the raising of fish by combining aquaculture with the techniques of hydroponics, usually on a small scale. Water containing fish waste matter is used as the nutri...

Herrick, Robert, American novelist

(Encyclopedia)Herrick, Robert, 1868–1938, American novelist, b. Cambridge, Mass., grad. Harvard, 1890. He was professor of English at the Univ. of Chicago from 1893 to 1923. Herrick wrote realistic social novels ...

coagulation

(Encyclopedia)coagulation kōăgˌyo͞olāˈshən [key], the collecting into a mass of minute particles of a solid dispersed throughout a liquid (a sol), usually followed by the precipitation or separation of the s...

shock wave

(Encyclopedia)shock wave, wave formed of a zone of extremely high pressure within a fluid, especially the atmosphere, that propagates through the fluid at a speed in excess of the speed of sound. A shock wave is ca...

Soufrière, volcano, St. Vincent

(Encyclopedia)Soufrière, volcano, 4,048 ft (1,234 m) high, on St. Vincent island, St. Vincent and the Grenadines. On May 7, 1902, the day before the great eruption of Pelée on Martinique island, Soufrière erupte...