oedipusphinx — — — — theJWDban
circular pair of fluorescent tubes flickering from the ceiling
two fluorescent tubes in the shape of rings; one is shining whitish, the other one yellowish.
A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful light more efficiently than an incandescent lamp. Lower energy cost typically offsets the higher initial cost of the lamp. The lamp is more costly because it requires a ballast to regulate the flow of current through the lamp.
construction
A fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon, xenon, neon, or krypton. The pressure inside the lamp is around 0.3% of atmospheric pressure. The inner surface of the bulb is coated with a fluorescent (and often slightly phosphorescent) coating made of varying blends of metallic and rare-earth phosphor salts. The bulb's cathode is typically made of coiled tungsten that is coated with a mixture of barium, strontium and calcium oxides (chosen to have a relatively low thermionic emission temperature).
Ballast Fluorescent lamps require a ballast to stabilize the current through the lamp, and to provide the initial striking voltage required to start the arc discharge. This increases the cost of fluorescent light fixtures, though often one ballast is shared between two or more lamps. Electromagnetic ballasts with a minor fault can produce an audible humming or buzzing noise. Magnetic ballasts are usually filled with a tar-like potting compound to reduce emitted noise. Hum is eliminated in lamps with a high-frequency electronic ballast. Energy lost in magnetic ballasts can be significant, on the order of 10% of lamp input power.[21] Electronic ballasts reduce this loss.
flicker problems Fluorescent lamps using a magnetic mains frequency ballast do not give out a steady light; instead, they flicker at twice the supply frequency. This results in fluctuations not only with light output but color temperature as well, which may pose problems for photography and people who are sensitive to the flicker. Even among persons not sensitive to light flicker, a stroboscopic effect can be noticed, where something spinning at just the right speed may appear stationary if illuminated solely by a single fluorescent lamp. This effect is eliminated by paired lamps operating on a lead-lag ballast. Unlike a true strobe lamp, the light level drops in appreciable time and so substantial "blurring" of the moving part would be evident.
Atmosphäre der Erde stammt aus dem All
... Fachjournal Science vol 326, p 1522) veröffentlicht. Die Erdatmosphäre und die Ozeane sind demnach wahrscheinlich nach Einschlägen kometenähnlichen Materials entstanden, das reich an Gas und Wasser war. "Viele Menschen kennen die künstlerische Deutung der Urerde mit riesigen Vulkanen im Hintergrund, die zur Formung der Atmosphäre Gas ausspeien", schreibt Studienleiter Chris Ballentine von der Universität Manchester. "Wir werden dieses Bild neu zeichnen müssen."
Die Forscher hatten die chemische Signatur der Edelgase Krypton und Xenon untersucht. Ihr "Fingerabdruck" entspricht demnach dem von Meteoriten. Erst neueste Technik habe die Analyse möglich gemacht, schreiben die Forscher.
Gas Leak Inspection
The solid portion of Earth was formed from accretion of material and debris formed in the primitive Solar System. Earth’s early evolution included the differentiation of its interior and the development of a primordial atmosphere. Heavy noble gases in the atmosphere could have been acquired during the initial accretion process or may have accumulated later through gravitational volatile capture. Holland et al. (p. 1522) show that Krypton and Xenon trapped in the upper mantle have isotopic signatures characteristic of early Solar System material similar to meteorites rather than those of the modern atmosphere and oceans. Thus, noble gases trapped within the young Earth did not contribute to Earth’s later atmospheric composition.
www.marytown.cn/wordpress/2009/12/11/rice-pathogenic-bact..., By Lord Rayleigh, F.R.S. (received 15 December 1938) part I, Neon and Argon. Vol. CLXX, A. {21.April 1939} [451]
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photo is spread with credits to:
...Invitation 2 Inquiry @ slideshare 7/16
...RePosted on March 22, 2010 by viviviee @ posterous
... Tubi Fluorescenti e Lampade Circolari Fluorescenti @ mygreenbuildings Le lampade a tubi fluorescenti, le seconde lampade più popolari, hanno un’efficienza energetica di gran lunga superiore rispetto alle più popolari lampade ad incandescenza. I tubi fluorescenti più utilizzati sono indicati con la sigla T4, T5, T8, rispettivamente con diametro di 12.5 mm, 16.0 mm, 26.0 mm. I tubi fluorescenti sono più adatti per grandi spazi interni perchè la loro bassa luminosità crea un abbagliamento meno diretto rispetto alle lampade ad incandescenza. Le lampade fluorescenti circolari sono più adatte per ottenere un’illuminazione simmetrica e comunque per spazi non troppo grandi.
... fluorescent tubes @ cyclo-zen
... Lamps Media @ homeimprovements
... circular pair of fluorescent tubes @ djibnet.fr
... circular pair of fluorescent tubes 無料・フリー素材/写真 @ igosso.jp
.... Expect Higher Priced Electricity, Natural Gas Posted by D. Scott Beaver on Mon, May 17, 2010
circular pair of fluorescent tubes flickering from the ceiling
two fluorescent tubes in the shape of rings; one is shining whitish, the other one yellowish.
A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful light more efficiently than an incandescent lamp. Lower energy cost typically offsets the higher initial cost of the lamp. The lamp is more costly because it requires a ballast to regulate the flow of current through the lamp.
construction
A fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon, xenon, neon, or krypton. The pressure inside the lamp is around 0.3% of atmospheric pressure. The inner surface of the bulb is coated with a fluorescent (and often slightly phosphorescent) coating made of varying blends of metallic and rare-earth phosphor salts. The bulb's cathode is typically made of coiled tungsten that is coated with a mixture of barium, strontium and calcium oxides (chosen to have a relatively low thermionic emission temperature).
Ballast Fluorescent lamps require a ballast to stabilize the current through the lamp, and to provide the initial striking voltage required to start the arc discharge. This increases the cost of fluorescent light fixtures, though often one ballast is shared between two or more lamps. Electromagnetic ballasts with a minor fault can produce an audible humming or buzzing noise. Magnetic ballasts are usually filled with a tar-like potting compound to reduce emitted noise. Hum is eliminated in lamps with a high-frequency electronic ballast. Energy lost in magnetic ballasts can be significant, on the order of 10% of lamp input power.[21] Electronic ballasts reduce this loss.
flicker problems Fluorescent lamps using a magnetic mains frequency ballast do not give out a steady light; instead, they flicker at twice the supply frequency. This results in fluctuations not only with light output but color temperature as well, which may pose problems for photography and people who are sensitive to the flicker. Even among persons not sensitive to light flicker, a stroboscopic effect can be noticed, where something spinning at just the right speed may appear stationary if illuminated solely by a single fluorescent lamp. This effect is eliminated by paired lamps operating on a lead-lag ballast. Unlike a true strobe lamp, the light level drops in appreciable time and so substantial "blurring" of the moving part would be evident.
Atmosphäre der Erde stammt aus dem All
... Fachjournal Science vol 326, p 1522) veröffentlicht. Die Erdatmosphäre und die Ozeane sind demnach wahrscheinlich nach Einschlägen kometenähnlichen Materials entstanden, das reich an Gas und Wasser war. "Viele Menschen kennen die künstlerische Deutung der Urerde mit riesigen Vulkanen im Hintergrund, die zur Formung der Atmosphäre Gas ausspeien", schreibt Studienleiter Chris Ballentine von der Universität Manchester. "Wir werden dieses Bild neu zeichnen müssen."
Die Forscher hatten die chemische Signatur der Edelgase Krypton und Xenon untersucht. Ihr "Fingerabdruck" entspricht demnach dem von Meteoriten. Erst neueste Technik habe die Analyse möglich gemacht, schreiben die Forscher.
Gas Leak Inspection
The solid portion of Earth was formed from accretion of material and debris formed in the primitive Solar System. Earth’s early evolution included the differentiation of its interior and the development of a primordial atmosphere. Heavy noble gases in the atmosphere could have been acquired during the initial accretion process or may have accumulated later through gravitational volatile capture. Holland et al. (p. 1522) show that Krypton and Xenon trapped in the upper mantle have isotopic signatures characteristic of early Solar System material similar to meteorites rather than those of the modern atmosphere and oceans. Thus, noble gases trapped within the young Earth did not contribute to Earth’s later atmospheric composition.
www.marytown.cn/wordpress/2009/12/11/rice-pathogenic-bact..., By Lord Rayleigh, F.R.S. (received 15 December 1938) part I, Neon and Argon. Vol. CLXX, A. {21.April 1939} [451]
..................................................................................................
photo is spread with credits to:
...Invitation 2 Inquiry @ slideshare 7/16
...RePosted on March 22, 2010 by viviviee @ posterous
... Tubi Fluorescenti e Lampade Circolari Fluorescenti @ mygreenbuildings Le lampade a tubi fluorescenti, le seconde lampade più popolari, hanno un’efficienza energetica di gran lunga superiore rispetto alle più popolari lampade ad incandescenza. I tubi fluorescenti più utilizzati sono indicati con la sigla T4, T5, T8, rispettivamente con diametro di 12.5 mm, 16.0 mm, 26.0 mm. I tubi fluorescenti sono più adatti per grandi spazi interni perchè la loro bassa luminosità crea un abbagliamento meno diretto rispetto alle lampade ad incandescenza. Le lampade fluorescenti circolari sono più adatte per ottenere un’illuminazione simmetrica e comunque per spazi non troppo grandi.
... fluorescent tubes @ cyclo-zen
... Lamps Media @ homeimprovements
... circular pair of fluorescent tubes @ djibnet.fr
... circular pair of fluorescent tubes 無料・フリー素材/写真 @ igosso.jp
.... Expect Higher Priced Electricity, Natural Gas Posted by D. Scott Beaver on Mon, May 17, 2010