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adhesive

(Encyclopedia)adhesive, substance capable of sticking to surfaces of other substances and bonding them to one another. The term adhesive cement is sometimes used in place of adhesive, especially when referring to a...

radar astronomy

(Encyclopedia)radar astronomy, application of radar to the determination of distances and planetary features within the solar system, such as rotation rates. A short burst of radio waves is transmitted in the direc...

adsorption

(Encyclopedia)adsorption, adhesion of the molecules of liquids, gases, and dissolved substances to the surfaces of solids, as opposed to absorption, in which the molecules actually enter the absorbing medium (see a...

ytterbium

(Encyclopedia)ytterbium ĭtûrˈbēəm [key] [for Ytterby, a town in Sweden], metallic chemical element; symbol Yb; at. no. 70; at. wt. 173.054; m.p. 819℃; b.p. about 1,194℃; sp. gr. about 7.0; valence +2 or +3...

rammed earth

(Encyclopedia)rammed earth, material consisting chiefly of soil of sufficiently stiff consistency that has been placed in forms and pounded down. It has been used for buildings and walls since ancient times and was...

Pilgrimage of Grace

(Encyclopedia)Pilgrimage of Grace, 1536, rising of Roman Catholics in N England. It was a protest against the government's abolition of papal supremacy (1534) and confiscation (1536) of the smaller monastic propert...

electromagnetic radiation

(Encyclopedia)CE5 Electromagnetic spectrum electromagnetic radiation, energy radiated in the form of a wave as a result of the motion of electric charges. A moving charge gives rise to a magnetic field, and if ...

designer drug

(Encyclopedia)designer drug, chemical substance synthesized in a laboratory that is intended to have effects similar to those of a drug that is a controlled substance, such as methamphetamine, marijuana, LSD, or an...

hallucinogenic drug

(Encyclopedia)hallucinogenic drug həlo͞oˌsənōjĕnˈĭk [key], any of a group of substances that alter consciousness; also called psychotomimetic (i.e., mimicking psychosis), mind-expanding, or psychedelic drug...

quantum electrodynamics

(Encyclopedia)quantum electrodynamics (QED), quantum field theory that describes the properties of electromagnetic radiation and its interaction with electrically charged matter in the framework of quantum theory. ...