Hydrophobic Solvation of Gases (CO2, CH4, H2, Noble Gases ...
Noble Gas Discharges(RaphaelMehlich) - fh-muenster.de · PtiProperties off noblble gases All noble...
Transcript of Noble Gas Discharges(RaphaelMehlich) - fh-muenster.de · PtiProperties off noblble gases All noble...
NOBLE GAS DISCHARGESNOBLE GAS DISCHARGES
21.Juni.2010Raphael Mehlich
I dIndex History of noble gases History of noble gases
Properties of noble gasesProperties of noble gases
High pressure discharge lampsg p g p
Glow lamps
Noble gas excimer
21.Juni.2010Raphael Mehlich
Hi t f bl History of noble gases 868 Jules Janssen and Norman Lockler disco ered Helium 1868: Jules Janssen and Norman Lockler discovered Helium 1892: Luigi Palmieri verified Helium
8 L d R l i h h di d A 1894: Lord Rayleigh has discovered Argon 1898: Lord Rayleigh and Morris William Travers verified N X d K t b f ti l di till ti f iNeon, Xenon and Krypton by fractional distillation of air
1900: Friedrich Ernst Dorn discovered Radon U i d b h I i f N l 2006: Ununoctium was made by the Institute for Nuclear
Research and the Lawrence Livermore National Laboratory
21.Juni.2010Raphael Mehlich
P ti f bl Properties of noble gases All noble gases are odorless colorless nontoxic incombustible under All noble gases are odorless, colorless, nontoxic, incombustible under
normal conditions and are stable in a non‐molecular state
21.Juni.2010Raphael Mehlich
Hi h P Di h L High Pressure Discharge Lamps • Pressure of noble (Xe) gas 5 20 bar• Pressure of noble (Xe) gas 5‐20 bar
during operation 12‐100 bar• Ignition voltage 20‐30 kVIgnition voltage 20 30 kV
operating voltage 30 V• Distance of electrodes 0,2mm to
several mm• Quantum efficiency 40 lm/Watt• Comparable to solar spectrum
color temperature ~ 6000 K
21.Juni.2010Raphael Mehlich
A li ti f Di h LApplication for Discharge Lamp• Vis Spectroscopy (400 800 nm)• Vis‐Spectroscopy (400‐800 nm)• Projector• SpotlightSpotlight• Purification of water• Pros:‐ bright light‐ homogeneous spectrum (400‐800nm)
• Cons:‐ formation of ozone‐ short lifetime (several 1000h)‐ short lifetime (several 1000h)‐ high technical effort‐ safety requirement
21.Juni.2010Raphael Mehlich
Gl Di h LGlow Discharge Lamps• Pressure of noble gas (Xe) • Pressure of noble gas (Xe)
less than 10‐2mbar• Operating voltage < 100VOperating voltage < 100V• Color depends on applied noble gas• Cold bulb
21.Juni.2010Raphael Mehlich
A li tiApplicationsAd ertisement• Advertisement
• Phase checker• Pros:‐ cold bulb‐ pure color s
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E iExcimers• Excimer = excited dimers• Dimer: two noble gas atoms (Xe2*,Ar2*,…) or noble
gas halides (XeF*,KrCl*)E i l bl i i d • Excimer are only stable in excited state
• R* + R R2*R+ + X‐ + M RX* + MR+ + X + M RX* + MR* + X2 RX* + X
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A li ti f E i Di h Applications of ExcimerDischarges Light Screens (Planon® ) Light Screens (Planon® ) Excimer Laser High power Cold UV High power Cold UV
Excimer System
Planon®
21.Juni.2010Raphael Mehlich
Pl TV Plasma TV Noble gases Noble gases
Xe for 148 and 172 nmNe for orange rangeNe for orange range
Excitation of Xe atoms by electron collision
UV Radiation is converted by phosphor into visible light
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SSources Hans‐Jörg Bullinger – Technologieführer Springer Verlag Berlin (2007)Hans Jörg Bullinger Technologieführer, Springer Verlag, Berlin (2007) Dieter Meschede – Gerthsen Physik, Springer Verlag, Berlin (2006) Erwin Riedel – Anorganische Chemie, Walter de Gruyter Verlag, Berlin
(2004)(2004) Wolfgang Demtröder – Experimentalphysik 3, Springer Verlag, Berlin
(2010) Joachim Staab ‐ Industriele Gasanalyse Oldenbourg Verlag München Joachim Staab ‐ Industriele Gasanalyse, Oldenbourg Verlag, München
(1994)
http://wwwelektronikinfo de/strom/thermischelampen htm http://www.elektronikinfo.de/strom/thermischelampen.htm http://www.uni‐muenster.de/Physik.TD/gasentladungslampen.html http://www.heraeus‐noblelight.com http://www.newport.com http://www.uni‐protokolle.de
21.Juni.2010Raphael Mehlich