fluorescence

fluorescence
Emission of a longer wavelength radiation by a substance as a consequence of absorption of energy from a shorter wavelength radiation, continuing only as long as the stimulus is present; distinguished from phosphorescence, which emission persists for a perceptible period of time after the stimulus has been removed. See photoelectric effect. [fluorspar + -escence, inchoative suffix]

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flu·o·res·cence -'es-ən(t)s n luminescence that is caused by the absorption of radiation at one wavelength followed by nearly immediate reradiation usu. at a different wavelength and that ceases almost immediately when the incident radiation stops also the radiation emitted
flu·o·res·cent -'es-ənt adj

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n.
the emission of light by a material as it absorbs radiation from outside. The radiation absorbed may be visible or invisible (e.g. ultraviolet rays or X-rays).
fluorescent adj.

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flu·o·res·cence (fl-resґəns) [first observed in fluorspar] the property of emitting light while exposed to light, the wavelength of the emitted light being only slightly longer than that of the light absorbed. Cf. phosphorescence.

Medical dictionary. 2011.

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  • fluorescence — [ flyɔresɑ̃s ] n. f. • 1856; mot angl. (1852), de fluor, d apr. phosphorescence ♦ Phys. Luminescence d une substance (solide, liquide ou gaz) due à une transition spontanée des molécules, d un état excité vers l état fondamental. Fluorescence… …   Encyclopédie Universelle

  • Fluorescence — Flu o*res cence, n. [From {Fluor}.] (Chemistry, Optics) A luminescence emitted by certain substances due to the absorption of radiation at one wavelength, and the almost instantaneous re emission of radiation at another, usually longer wavelength …   The Collaborative International Dictionary of English

  • fluorescence — 1852, glowing in ultraviolet light, coined by English mathematician and physicist Sir George G. Stokes (1819 1903) from fluorspar (see FLUORINE (Cf. fluorine)), because in it he first noticed the phenomenon, + ESCENCE (Cf. escence), on analogy of …   Etymology dictionary

  • fluorescence —  Fluorescence  Флуоресценция   Кратковременная люминесценция. Излучательный переход между двумя состояниями одинаковой мультиплетности (синглетными или триплетными уровнями). Флуоресценция наблюдается в жидкой, твердой и газовой фазах. При… …   Толковый англо-русский словарь по нанотехнологии. - М.

  • fluorescence — ► NOUN 1) light emitted by a substance when it is exposed to radiation such as ultraviolet light or X rays. 2) the property of emitting light in this way. ORIGIN from FLUORSPAR(Cf. ↑F) (which fluoresces), on the pattern of opalescence …   English terms dictionary

  • fluorescence — [flo͞o΄ə res′əns] n. [< FLUOR(SPAR) + ESCENCE] 1. the property of a substance, such as fluorite, of producing light while it is being acted upon by ultraviolet rays, X rays, or other forms of radiant energy 2. the production of such light 3.… …   English World dictionary

  • Fluorescence — Fluorescent minerals emit visible light when exposed to ultraviolet light Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength.[1] It is a form of luminescence.… …   Wikipedia

  • Fluorescence X — Spectrométrie de fluorescence X Pour les articles homonymes, voir SFX, FX et XRF. Un spectromètre de fluorescence X Philips PW1606 avec manutention automatiq …   Wikipédia en Français

  • Fluorescence — La fluorescence est une émission lumineuse provoquée par l excitation d une molécule (généralement par absorption d un photon) immédiatement suivie d une émission spontanée. Ce processus est différent de la phosphorescence. La fluorescence peut… …   Wikipédia en Français

  • fluorescence — /floo res euhns, flaw , floh /, n. Physics, Chem. 1. the emission of radiation, esp. of visible light, by a substance during exposure to external radiation, as light or x rays. Cf. phosphorescence (def. 1). 2. the property possessed by a… …   Universalium

  • fluorescence — (flu o rè ssan s ) s. f. Terme de physique. Éclairement particulier que présentent certaines substances lorsqu elles sont exposées à l action des parties les plus réfrangibles de la radiation lumineuse, c est à dire à l action des rayons… …   Dictionnaire de la Langue Française d'Émile Littré

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