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nobelium

(Encyclopedia)nobelium nōbēˈlēəm [key], artificially produced radioactive chemical element; symbol No; at. no. 102; mass no. of most stable isotope 259; m.p. 827℃; b.p. and density unknown; valence +2, +3. I...

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...

supersymmetry

(Encyclopedia)supersymmetry, in physics, theory concerning the relationship of the elementary particles called boson to those known as fermions, and vice versa, and linking the four fundamental forces. In supersymm...

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...

verb

(Encyclopedia)verb, part of speech typically used to indicate an action. English verbs are inflected for person, number, tense and partially for mood; compound verbs formed with auxiliaries (e.g., be, can, have, do...

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...

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...

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...

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. ...