Research Area :Laboratory Studies of Homogeneous and Heterogeneous Atmospheric Processes.

Major Kinetic Tools (see schematics and Photos below):

Gas-Phase Kinetic and Photochemical studies: Laser-Flash-Photolysis and Flow Tube techniques.
Heterogeneous Reactions :  Flow-tubes and Knudsen Reactor

Detection Methods: Laser Induced Fluorescence    Resonance Fluorescence    UV/Vis absorption    Mass Spectrometry    IR absorption.

Pulsed Laser Photolysis with Pulsed Laser Induced / Resonance Fluorescence
PLP-PLIF-SchematicPLP-PLIF-Photo1PLP-PLIF-Photo2

Pulsed Laser Photolysis (Excimer / YAG) with UV-Vis Absorption / Resonance Fluorescence
PLP-UV-Schematic PLP-UV-Photo

Aerosol Flow Tube / Optical Particle Counter / Chemi-Luminescence Detector

Wetted Wall Flow Tube / Mass Spectrometer
WWFT-Schematic

Coated Wall Flow Tube / Mass Spectrometer
CWFT-SchematicCWFT-Photo1CWFT-Photo2

Knudsen Reactor / Mass spectrometer
KNUD-SchematicKNUD-Photo
 

Recent and Present International Project Participation

GIF                               Mineral dust particles and their influence on cloud characteristics (1999-2002)

CUT-ICE                      Chemistry of the Upper Troposphere, Heterogeneous Processes on Ice (2000-2003)

MINATROC                 Mineral dust and Tropospheric Chemistry (2000-2003)

AFO2000-CORBIC     Chemistry of Reactive Bromine and Iodine Compounds (2001-2004)

THALOZ                      Tropospheric HALogens-effect on OZone (2002 - 2005)

UTOPIHAN-ACT      Upper Tropospheric Ozone, Processes Involving HOx And NOx. Impact of Aviation and Convection (2002-2004)
 
 

Post-docs and Students:

Terry Dillon
Friedrich Hanisch
Dirk Hölscher
Nick Holmes
Sivakumaran V.
Mariano Teruel
Karoline Winkler

Recent Publications

Ingham, T., Cameron, M. and Crowley, J.N, Photodissociation of IO (355 nm) and OIO (532 nm): Quantum yields for O(3P) / I production, J. Phys. Chem., 104, 8001-8010, 2000.

Knight, G.P., T. Beiderhase, F. Helleis, G.K. Moortgat, and J.N. Crowley, The reaction of HO2 with ClO: Flow tube studies of kinetics and product formation between 215 and 298 K, J. Phys. Chem., 104, 1674-1685, 2000.

Röckmann, T., C.A.M. Brenninkmeijer, N. Wollenhaupt, J.N. Crowley, and P.J. Crutzen, Measurement of the isotopic fractionation of 15N14N16O, 14N15N16O and 14N14N18O in the UV photolysis of nitrous oxide, Geophys. Res. Lett., 27, 1399-1402, 2000.

Wollenhaupt, M., S.A. Carl, A. Horowitz, and J.N. Crowley, Rate coefficients for reaction of OH with acetone between 202 and 395 K, J. Phys. Chem., 104, 2695-2705, 2000.

Wollenhaupt, M., and J.N. Crowley, Kinetic studies of the reactions: OH + CH3C(O)CH3 ->  CH3C(O)OH + CH3 , CH3 + NO2 ->products, and CH3O + NO2 -> Products at a range of temperatures and pressures, J. Phys. Chem., 104, 6429-6438, 2000

Knight, G.P. and J.N. Crowley, The reactions of IO with HO2, NO and CH3SCH3: Flow tube studies of kinetics and product formation, Phys. Chem. Chem. Phys., 3, 393-401, 2001.

Röckmann, T., J. Kaiser,  J.N. Crowley, C.A.M. Brenninkmeijer, and P.J. Crutzen, The origin of the anomalous or "mass-independent" oxygen isotope fractionation in atmospheric N2O,  Geophys. Res. Lett. 28, 503-506, 2001.

Holmes, N.S., J.W. Adams and J.N. Crowley, Uptake and reaction of HOI and IONO2 on frozen and dry NaCl / NaBr surfaces and H2SO4, Phys. Chem. Chem. Phys., 3, 1679-1687, 2001

Hanisch, F., and J.N. Crowley, Heterogeneous reactivity of gaseous nitric acid on Al2O3, CaCO3 and atmospheric dust samples: A knudsen cell study, J. Phys. Chem., 105, 3096-3106, 2001.

Röckmann, T., J. Kaiser,  C.A.M. Brenninkmeijer, J.N. Crowley, R. Borchers, W.A. Brand, and P.J. Crutzen, Isotopic enrichment of nitrous oxide (15N14NO, 14N15NO, 14N14N18O) in the stratosphere and in the laboratory, J. Geophys. Res. 106, 10403, 2001.

Hanisch, F., and J.N. Crowley, The heterogeneous reactivity of gaseous nitric acid on authentic mineral dust samples, and on individual mineral and clay mineral components, Phys. Chem. Chem. Phys. 3, 2474-2482,2001.

S.A. Carl, T. Ingham, G.K. Moortgat, and J.N. Crowley, OH kinetics and photochemistry of HNO3 in the prsence of water vapour, Chem. Phys. Lett. 341, 93-98, 2001.

G. Saueressig, J.N. Crowley, P. Bergamaschi, Ch. Brühl, C.A.M. Brenninkmeijer and H. Fischer, 13C and D kinetic isotope effects in the reactions of CH4 with O1D and OH: New laboratory measurements and their implications for the isotopic compoition of stratospheric methane, J. Geophys. Res. 106, 23127, 2001.

S.A. Carl and J.N. Crowley, 298 K rate coefficients for the reaction of OH with i-C3H7i, n-C3H7i and C3H8, Atmos. Chem. Phys.  1, 1-7, 2001.

J.W. Adams, N.S. Holmes and J.N. Crowley, Uptake and reaction of HOBr on frozen and dry NaCl/NaBr surfaces betwen 253 and 233 K, Atmos. Chem. Phys.  2, 79-91, 2002.

M. Cameron, V. Sivakumaran, T.J. Dillon and J.N. Crowley, Reaction between OH and CH3CHO: 1. Primary product yields of CH3 (296 K), CH3CO (296 K) and H (237-296 K), Phys. Chem. Chem. Phys. in press, 2002.