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gum, colloidal plant substance

(Encyclopedia)gum, term commonly applied to any of a wide variety of colloidal substances somewhat similar in appearance and general characteristics, exuded by or extracted from plants. In this classification, howe...

solid

(Encyclopedia)solid, one of the three commonly recognized states in which matter occurs, i.e., that state, as distinguished from liquid and gas, in which a substance has both a definite shape and a definite volume....

photoelectric effect

(Encyclopedia)photoelectric effect, emission of electrons by substances, especially metals, when light falls on their surfaces. The effect was discovered by H. R. Hertz in 1887. The failure of the classical theory ...

Yokohama

(Encyclopedia)Yokohama yōˌkōhäˈmä [key], city (1990 pop. 3,220,331), capital of Kanagawa prefecture, SE Honshu, Japan, on the western shore of Tokyo Bay. Japan's second largest city and one of its leading sea...

caravan

(Encyclopedia)caravan, group of travelers or merchants banded together and organized for mutual assistance and defense while traveling through unsettled or hostile country. Caravan trade is associated with the hist...

milling

(Encyclopedia)milling, mechanical grinding of wheat or other grains to produce flour. Milling separates the fine, mealy parts of grain from the fibrous bran covering. In prehistoric times grain was crushed between ...

3D printer

(Encyclopedia)3D printer, computerized device that produces a three-dimensional object by creating it as a series of thin layers. The object is created from a model stored in computer-aided design file; the model i...

commodity market

(Encyclopedia)commodity market, organized traders' exchange in which standardized, graded products are bought and sold. Worldwide, there are more than 20 major commodity exchanges and many smaller ones that trade c...

promethium

(Encyclopedia)promethium prōmēˈthēəm [key], artificially produced radioactive chemical element; symbol Pm; at. no. 61; mass no. of most stable isotope 145; m.p. 1,042℃; b.p. 3,000℃ (estimated); sp. gr. unk...

El Paso

(Encyclopedia)El Paso ĕl păˈsō [key], city (2020 pop. 678,815), seat of El Paso co., extreme W Tex., on ...