550 likes | 791 Views
ATMOSFERSKA KEMIJA Dio slika je iz kolegija koji je prošle godine vodio prof. Udo Frieß, Institut za fiziku okoliša Ruprecht-Karls Sveučilišta u Heidelbergu. N 2 O. NO 2. NO 2 pollution levels in Europe, from January 2003 to June 2004. Claude Monet, 1900. Great London smog of 1952.
E N D
ATMOSFERSKA KEMIJA Dio slika je iz kolegija koji je prošle godine vodio prof. Udo Frieß, Institut za fiziku okoliša Ruprecht-Karls Sveučilišta u Heidelbergu.
N2O NO2
NO2 pollution levels in Europe, from January 2003 to June 2004.
Claude Monet, 1900 Great London smog of 1952
Inversion Smoke rising in Lochcarron is stopped by an overlying layer of warmer air.
Dichlorodifluoromethane, CFC-12, Freon 12 Trichlorofluoromethane, CFC-11, Freon 11
Aerosol Chamber (Top View) Atmospheric Pressure Ionization Mass Spec (API-MS) FTIR Q1 Q3 560L Stainless Steel and Aluminum Chamber Spectrometer CEM MCT photolysis lamps Xe lamp P, T, %RH CPC gas inlet Spectrometer water regulated temperature control DMA Differential Optical Absorption Spectroscopy (DOAS) Aerosol Generation and Measurement Aerosol interfacial chemistry Barbara J. Finlayson-Pitts UC Irvine, 1997 • Add NaCl particles to chamber • Add humid air to a relative humidity above NaCl deliquescence point Formation of Hydroxyl Radicals Water Vapor: H2O Excited Oxygen Atom: O(1D) Hydroxyl Radical: OH + • Add ozone • Photolyze at 254 nm (generate OH radicals) • Measure gaseous reactants and products using FTIR, DOAS, and API-MS. + Hydroxyl Radical: OH Ozone: O3 Molecular Oxygen: O2 Slide by Eladio Knipping
O3 , H2O2 OH OH + Cl– O3 , H2O2 Known Aqueous Phase Chemistry Cl– O3 OH Cl2 Cl2 OH•Cl– + OH•Cl– Cl2 2 OH– Potential Surface Reactions Proposed Mechanism for Cl2 Production Knipping,, Lakin, Foster Jungwirth, Tobias, Gerber, Dabdub, Finlayson-Pitts, Science, April 2000 IRVINE-PRAGUE-JERUSALEM collaboration