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brake, in technology

(Encyclopedia)CE5 Shoe brake CE5 Disk brake brake, in technology, device to slow or stop the motion of a mechanism or vehicle. The vacuum brake system, or vacuum brake, depends upon the use of a vacuum to ...

metallurgy

(Encyclopedia)metallurgy mĕtˈəlûrˌjē [key], science and technology of metals and their alloys. Modern metallurgical research is concerned with the preparation of radioactive metals, with obtaining metals econ...

mountain

(Encyclopedia)mountain, high land mass projecting conspicuously above its surroundings and usually of limited width at its summit. Although isolated mountains are not unusual, mountains commonly form ranges, compri...

museums of science

(Encyclopedia)museums of science, institutions or buildings where collections relevant to science and technology are preserved and displayed to promote education and research. While the preponderance of these museu...

rock

(Encyclopedia)rock, aggregation of solid matter composed of one or more of the minerals forming the earth's crust. The scientific study of rocks is called petrology. Rocks are commonly divided, according to their o...

heroin

(Encyclopedia)heroin hĕˈrəwən [key], opiate drug synthesized from morphine (see narcotic). Originally produced in 1874, it was thought to be not only nonaddictive but useful as a cure for respiratory illness an...

submarine

(Encyclopedia)submarine, naval craft capable of operating for an extended period of time underwater. Submarines are almost always warships, although a few are used for scientific, business, or other purposes (see a...

space medicine

(Encyclopedia)space medicine, study of the medical and biological effects of space travel on living organisms. The principal aim is to discover how well and for how long humans can withstand the extreme conditions ...

periodic table

(Encyclopedia)CE5 periodic table, chart of the elements arranged according to the periodic law discovered by Dmitri I. Mendeleev and revised by Henry G. J. Moseley. In the periodic table the elements are arrange...

petroleum

(Encyclopedia)petroleum, oily, flammable liquid that occurs naturally in deposits, usually beneath the surface of the earth; it is also called crude oil. It consists principally of a mixture of hydrocarbons, with t...