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