SootParticle-AMS or

LaserVaporizer-AMS

Aerodyne Research, Inc.

et al.

SP-AMS Instruments in the Field

# Research Group Instrument Status

1 Aerodyne Research, Inc. SP module

2 Aerodyne Research, Inc. SP module

3 University of Manchester SP module delivered

4 University of Toronto SP-AMS delivered

5

Lund University, Division of Nuclear Physics,

Sweden SP module delivered

6

Swiss Federal Institute of Technology Zurich

(ETH), Institut für Atmosphäre und Klima, Zurich,

Switzerland SP module delivered

7 FMI Helsinki SP module delivered

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Laser Vaporizer

SP-AMS Orthogonal

Detection Axes

Sampled Particles

Ion Extraction and MS detection

• Characterization of particle-laser interaction region:

• Vertical Particle Beam Walk

• Horizontal/Vertical Beam Width Probe

• Horizontal/Vertical Laser Beam Walk

Ionizer Configurations

Standard AMS

• Filaments on sides of ion chamber

• Filament position is mechanically set

• Filament wire is typically well positioned with respect to well formed slits in ion chamber walls

SP-AMS

• Filament is on bottom of ion chamber

• Filament position is moveable (vert & horz)

• Filament slit width and breadth may vary due to custom procedure

• Large holes in sides to accommodate laser beam

Detection Scheme

SootParticle-AMS Refractory Black Carbon (rBC)

“Refractory black carbon” is used here specifically to indicate

an aerosol component with a color temperature (determined

through the SP2 color-ratio measurement) in a range seen to

be uniquely associated with laboratory black carbon samples

and ambient rBC out of all tested aerosol constituents likely to

be found in the ambient (Schwarz et al. 2006).

Schwarz, J. P., J. R. Spackman, R. S. Gao, a. E. Perring, E. Cross, T. B.

Onasch, A. Ahern, et al. (2010) “The Detection Efficiency of the Single Particle

Soot Photometer.” Aerosol Science and Technology 44 (8): 612-628.

Refractory black carbon (rBC), defined as discussed above,

has been shown to be representative of the refractory

carbonaceous material produced in flames …[and] as the most

refractory and most strongly light absorbing carbonaceous

aerosol material in the atmosphere.

LaserVaporizer-AMS Measured Species

25oC 600oC 4000oC

NR-PM R-PM rBC

NR-PM = Nonrefractory Particulate Matter

R-PM = Refractory Particulate Matter

rBC = Refractory Black Carbon

Metals = Refractory Metals and Metalloids

Metals

The laser is not the vaporizer, the absorbing particles are the vaporizer!!

SP-AMS Vaporizer

Configurations

Vaporizer Measured Species

Tungsten NR-PM * E B

Laser (rBC + R-PMǂ + NR-PM

ǂ) * E S

Laser and Tungsten (rBC + R-PMǂ + NR-PM

ǂ) * E S + (NR-PM - NR-PM

ǂ * E S ) * E B

NR-PM = Nonrefractory Particulate Material measured by a standard AMS [Jimenez et al., 2003 ]

R-PM = Refractory Particulate Material measured by the SP-AMS (see text for details)

rBC = Refractory black carbon measured by the SP-AMS (and SP2) [Schwarz et al., 2006 ]ǂ = Particulate Material on rBC particles as mesaured by the SP-AMS (see text for details)

E B = Particle bounce related Collection Efficiency of the AMS

E S = Size and shape related Collection Efficiency of the SP-AMS

Mass Spectral Information:

Denuded Flame Soot Black Carbon Signal Fraction

Calibration: mIErBC

mIErBC ~ 150 ions/pg

Nascent Flame Soot CE ~ 0.7

Denuded Flame Soot CE ~ 0.4

Calibrate versus CPMA/APM (lab), SMPS using effective densities, SP2

SP-AMS

Onasch et al. (AS&T 2012)

SP-AMS vs. SP2 Mass Loadings

CalNex2010

The CE is low when size is small.

Massoli et al., 2012

Particle Size Distributions:

DOS Coated Glassy Carbon Spheres

SP-AMS vs. SP2 Size Distributions

Particle Temperature Profiles

Particle

Temperature

Time Time

Laser Vaporizer Tungsten Vaporizer

600oC

NR-PM

R-PM

LVOOA

SVOOA

2

SVOOA

1

HOA

SP-AMS HR-AMS PMF

Similar PMF factor identification - slightly different spectra Massoli et al, 2012

Nascent Flame Soot Refractory Oxygen

Laser and Tungsten Vaporizers

Application Examples

Ambient Results

Fullerenic Fraction of Soot Ambient and

Vehicular Fortner, Williams et al.

Source Identification at Detling

Williams, Fortner et al.

Wood burning Vehicle Emissions

Mixing State of BC particles 1 NR-PM on BC particles

Cappa, Onasch, et al., Science 2012

Mixing State of BC particles 2 Mass fraction of BC aged

Cappa, Onasch, et al., Science 2012

Mass

Fra

ctio

n o

f B

C a

ged

Ambient Measurements and

BC2 Laboratory Results

Cappa, Onasch, et al., Science 2012 Cross, et al., Science 2010

Hydrocarbon and Black Carbon m/z Peaks

Additive-Derived m/z peaks

Diesel Exhaust Spectrum

Cross et al., 2012

Caldecott Tunnel

Dallmann, Harley et al., 2012

Absorbing Refractory Particles

• Refractory Black Carbon

• Metals

• Metalloids

Schwarz et al., 2004

Silver Nanoparticles

Sintered Unsintered

Pagels @ Lund et al.

Summary

• SP-AMS technology has matured and is opening new

avenues for applying MS to refractory particles

• Ambient refractory black carbon particles

– Mass loadings, size distributions, chemical compositions

– Fraction of total PM associated with BC containing particles

– RBC = PMBC/BC for BC containing particles

– Mass fraction of BC that is ‘fresh’ versus ‘aged’ (uncoated/coated)

– Primary Organic Aerosol (POA) chemical information

– Source identification and apportionment (fullerenes, refractory

metals)

• Metal nanoparticles in the laboratory

– Generation and process tracking