Aerosole
Transcription
Aerosole
Aerosole Tagesanzeiger, 27.6.2002 März 1992 Sonnenaufgang vom Space Shuttle: Junge Layer nach Ausbruch des Pinatubo Elektronenmikroskopie (X-ray-Fluorescence) A B C D E F G H I J K L Secondary electron image of North Sea aerosol particles: (A) Irregularly shaped seasalt particle; (B) sea-salt particle with typical cubic morphology (1), irregularlyshaped sea-salt particle (2), and alumosilicate particle (3); (C) aged sea-salt particle; (D) biological particle (1), Si-rich fly ash particle (2), and various soot particles (diameter of primary particles below 100 nm); (E) soot agglomerate (1) with alumosilicate particles (2, 4), and carbonaceous material (3); (F) alumosilicate particle (clay mineral); (G) two alumosilicate fly ash particles; (H) agglomeration of iron oxide spheres; (I) calcium sulphate (presumably gypsum) particle (1), spherical iron oxide particle (2), and titanium oxide particle (3); (J) typical soot agglomerate; (K) biological particle (1) and sea-salt (2); (L) agglomerate of carbonaceous material (1, 2), alumosilicates (3), Si-rich fly-ash (4), and calcium sulphate (5, 6). Ebert et al., J. Aerosol Sci., 31, 613-632, (2000) Mie-Streuung H.C. van de Hulst, Light Scattering by small Particles, 1957 FSSP (Forward Scattering Spectrometer Probe) 0.3 - 20 µm MASP (Multiangle Aerosol Spectrometer Probe) The MASP determines the size and concentration of particles from 0.3to 20 micrometers (um) diameter and the index of refraction for particles 0.4 to 0.7 um in diameter. The light scattered from individual particles passing through a 0.780 um wavelength laser beam is collected by optics over angles of 30-60 degrees in the forward direction and in the backward direction 120-150 degrees. The index of refraction is determined by comparing the ratio of forward to backscattered to the total scattered light and finding the best fit to Mie scattering theory. The size of the particle is determined from the total scattered light once the refractive index is determined. Lichtstreuung und Fluoreszenz Kaye et al., Appl. Opt., 39, 3738 (2000) Particle Sizer Scanning Mobility Particle Sizer (SMPS) DMA Differential Mobility Analyzer Condensation Particle Counter PALMS (Particle Analysis by Mass Spectroscopy) http://www.al.noaa.gov/WWWHD/Pubdocs/MetChem/PALMS/palms_home.html#top The probe on the nose of the WB-57 aircraft is the inlet for the PALMS instrument The periodic table of elements observed in aerosol particles by the PALMS instrument at altitudes above 5 km. Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) Aerodyne Aerosol Mass Spectrometer LIB(P)S: Laser Induced Breakdown (Plasma) Spectroscopy A plasma with high temperature and electron density is produced by a laser pulse witch is focused in a volume containing air and the ambient aerosol. This leads to a characteristic flash of light resulting from several subsequent mechanisms: bremsstrahlung (free - free), electron attachment and radiative recombination (free - bound), and radiative decay of exited atoms, ions, or molecules (bound - bound). LA-LIBS