Abstract

An optical particle counter (OPC) was exposed to atmospheric particles of diameters of 200, 300, and 400 nm. The OPC data were combined with the results of single-particle analysis with a transmission electron microscope (TEM) on samples taken in parallel with the OPC measurements. With a T-matrix-based optical model the measured OPC spectra of scattered light pulses could be approximated with good precision. With an algorithm that simulated the response of the OPC to a given population of model particles derived from the TEM results, average absorption properties of different particle types were retrieved. For mobility sizes of 400 nm, higher light absorption was retrieved with the optical model for soot aggregates than for the rest of the morphological particle types. At smaller mobility sizes no compositional information could be derived from the model particles derived from the TEM data. Despite the limited success of the new methodology applied to the present experiment the results encourage the use of OPCs in combination with electrical mobility analyzers to derive more than aerosol-size distributions. With state-of-the-art pulse-height analysis the light-scattering pulses could be resolved with much finer resolution than in the instrument used.

© 2004 Optical Society of America

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References

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  1. M. Kerker, “Light scattering instrumentation for aerosol studies: an historical overview,” Aerosol Sci. Technol. 27, 522–540 (1997).
    [CrossRef]
  2. H. C. van de Hulst, Light Scattering by Small Particles (Wiley, New York, 1957).
  3. D. S. Covert, J. Heintzenberg, H.-C. Hansson, “Electro-optical detection of external mixtures in aerosols,” Aerosol Sci. Technol. 12, 446–456 (1990).
    [CrossRef]
  4. S. V. Hering, P. H. McMurry, “Optical counter response to monodisperse atmospheric aerosols,” Atmos. Environ. 25A(2), 463–468 (1991).
  5. J. Heintzenberg, A. Massling, W. Birmili, “The connection between hygroscopic and optical particle properties in the atmospheric aerosol,” Geophys. Res. Lett. 28, 3649–3651 (2001).
    [CrossRef]
  6. R. G. Pinnick, J. M. Rosen, “Response of Knollenberg light-scattering counters to non-spherical doublet polystyrene latex aerosols,” J. Aerosol. Sci. 10, 533–538 (1979).
    [CrossRef]
  7. M. Quinten, R. Friehmelt, K.-F. Ebert, “Sizing of aggregates of spheres by a white-light optical particle counter with 90° scattering angle,” J. Aerosol. Sci. 32, 63–72 (2001).
    [CrossRef]
  8. J. M. Gérardy, M. Ausloos, “Absorption spectrum of clusters of spheres from the general solution of Maxwell’s equations,” Phys. Rev. B. 25, 4204–4210 (1982).
    [CrossRef]
  9. M. I. Mishchenko, “Light scattering by randomly oriented axially symmetric particles,” J. Opt. Soc. Am. A 8, 871–882 (1991).
    [CrossRef]
  10. S. Borrmann, B. Luo, M. Mishchenko, “Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters,” J. Aerosol. Sci. 31, 789–799 (2000).
    [CrossRef]
  11. J. Heintzenberg, K. Okada, B. P. Luo, “The distribution of optical properties among atmospheric submicrometer particles of given electrical mobilities,” J. Geophys. Res. 107, 4107, doi: 10.1029/2001JD000372(2002).
    [CrossRef]
  12. K. Okada, J. Heintzenberg, “Size distribution, state of mixture and morphology of urban aerosol particles at given electrical mobilities,” J. Aerosol. Sci. 34, 1539–1553 (2003).
    [CrossRef]
  13. W. Birmili, F. Stratmann, A. Wiedensohler, “Design of a DMA-based size spectrometer for a large particle size range and stable operation,” J. Aerosol. Sci. 30, 549–553 (1999).
    [CrossRef]
  14. W. E. Ranz, J. B. Wong, “Impaction of dust and smoke particles on surface and body collectors,” Ind. Eng. Chem. 44, 1371–1381 (1952).
    [CrossRef]
  15. M. I. Mishchenko, L. D. Travis, “Capabilities and limitations of a current Fortran implementation of the T-matrix method for randomly oriented rotationally symmetric scatterers,” J. Quant. Spectrosc. Radiat. Transfer. 60, 309–324 (1998).
    [CrossRef]
  16. R. G. Pinnick, J. D. Pendleton, G. Videen, “Response characteristics of the Particle Measuring Systems active scattering spectrometer probes,” Aerosol Sci. Technol. 33, 334–352 (2000).
    [CrossRef]
  17. H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
    [CrossRef]
  18. G. Hänel, “The real part of the mean complex refractive index and the mean density of samples of atmospheric aerosol particles,” Tellus 20, 371–379 (1968).
    [CrossRef]

2003 (1)

K. Okada, J. Heintzenberg, “Size distribution, state of mixture and morphology of urban aerosol particles at given electrical mobilities,” J. Aerosol. Sci. 34, 1539–1553 (2003).
[CrossRef]

2002 (2)

J. Heintzenberg, K. Okada, B. P. Luo, “The distribution of optical properties among atmospheric submicrometer particles of given electrical mobilities,” J. Geophys. Res. 107, 4107, doi: 10.1029/2001JD000372(2002).
[CrossRef]

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

2001 (2)

J. Heintzenberg, A. Massling, W. Birmili, “The connection between hygroscopic and optical particle properties in the atmospheric aerosol,” Geophys. Res. Lett. 28, 3649–3651 (2001).
[CrossRef]

M. Quinten, R. Friehmelt, K.-F. Ebert, “Sizing of aggregates of spheres by a white-light optical particle counter with 90° scattering angle,” J. Aerosol. Sci. 32, 63–72 (2001).
[CrossRef]

2000 (2)

S. Borrmann, B. Luo, M. Mishchenko, “Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters,” J. Aerosol. Sci. 31, 789–799 (2000).
[CrossRef]

R. G. Pinnick, J. D. Pendleton, G. Videen, “Response characteristics of the Particle Measuring Systems active scattering spectrometer probes,” Aerosol Sci. Technol. 33, 334–352 (2000).
[CrossRef]

1999 (1)

W. Birmili, F. Stratmann, A. Wiedensohler, “Design of a DMA-based size spectrometer for a large particle size range and stable operation,” J. Aerosol. Sci. 30, 549–553 (1999).
[CrossRef]

1998 (1)

M. I. Mishchenko, L. D. Travis, “Capabilities and limitations of a current Fortran implementation of the T-matrix method for randomly oriented rotationally symmetric scatterers,” J. Quant. Spectrosc. Radiat. Transfer. 60, 309–324 (1998).
[CrossRef]

1997 (1)

M. Kerker, “Light scattering instrumentation for aerosol studies: an historical overview,” Aerosol Sci. Technol. 27, 522–540 (1997).
[CrossRef]

1991 (2)

S. V. Hering, P. H. McMurry, “Optical counter response to monodisperse atmospheric aerosols,” Atmos. Environ. 25A(2), 463–468 (1991).

M. I. Mishchenko, “Light scattering by randomly oriented axially symmetric particles,” J. Opt. Soc. Am. A 8, 871–882 (1991).
[CrossRef]

1990 (1)

D. S. Covert, J. Heintzenberg, H.-C. Hansson, “Electro-optical detection of external mixtures in aerosols,” Aerosol Sci. Technol. 12, 446–456 (1990).
[CrossRef]

1982 (1)

J. M. Gérardy, M. Ausloos, “Absorption spectrum of clusters of spheres from the general solution of Maxwell’s equations,” Phys. Rev. B. 25, 4204–4210 (1982).
[CrossRef]

1979 (1)

R. G. Pinnick, J. M. Rosen, “Response of Knollenberg light-scattering counters to non-spherical doublet polystyrene latex aerosols,” J. Aerosol. Sci. 10, 533–538 (1979).
[CrossRef]

1968 (1)

G. Hänel, “The real part of the mean complex refractive index and the mean density of samples of atmospheric aerosol particles,” Tellus 20, 371–379 (1968).
[CrossRef]

1952 (1)

W. E. Ranz, J. B. Wong, “Impaction of dust and smoke particles on surface and body collectors,” Ind. Eng. Chem. 44, 1371–1381 (1952).
[CrossRef]

Ausloos, M.

J. M. Gérardy, M. Ausloos, “Absorption spectrum of clusters of spheres from the general solution of Maxwell’s equations,” Phys. Rev. B. 25, 4204–4210 (1982).
[CrossRef]

Birmili, W.

J. Heintzenberg, A. Massling, W. Birmili, “The connection between hygroscopic and optical particle properties in the atmospheric aerosol,” Geophys. Res. Lett. 28, 3649–3651 (2001).
[CrossRef]

W. Birmili, F. Stratmann, A. Wiedensohler, “Design of a DMA-based size spectrometer for a large particle size range and stable operation,” J. Aerosol. Sci. 30, 549–553 (1999).
[CrossRef]

Borrmann, S.

S. Borrmann, B. Luo, M. Mishchenko, “Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters,” J. Aerosol. Sci. 31, 789–799 (2000).
[CrossRef]

Covert, D. S.

D. S. Covert, J. Heintzenberg, H.-C. Hansson, “Electro-optical detection of external mixtures in aerosols,” Aerosol Sci. Technol. 12, 446–456 (1990).
[CrossRef]

Ebert, K.-F.

M. Quinten, R. Friehmelt, K.-F. Ebert, “Sizing of aggregates of spheres by a white-light optical particle counter with 90° scattering angle,” J. Aerosol. Sci. 32, 63–72 (2001).
[CrossRef]

Ebert, M.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

Friehmelt, R.

M. Quinten, R. Friehmelt, K.-F. Ebert, “Sizing of aggregates of spheres by a white-light optical particle counter with 90° scattering angle,” J. Aerosol. Sci. 32, 63–72 (2001).
[CrossRef]

Gérardy, J. M.

J. M. Gérardy, M. Ausloos, “Absorption spectrum of clusters of spheres from the general solution of Maxwell’s equations,” Phys. Rev. B. 25, 4204–4210 (1982).
[CrossRef]

Hänel, G.

G. Hänel, “The real part of the mean complex refractive index and the mean density of samples of atmospheric aerosol particles,” Tellus 20, 371–379 (1968).
[CrossRef]

Hansson, H.-C.

D. S. Covert, J. Heintzenberg, H.-C. Hansson, “Electro-optical detection of external mixtures in aerosols,” Aerosol Sci. Technol. 12, 446–456 (1990).
[CrossRef]

Heintzenberg, J.

K. Okada, J. Heintzenberg, “Size distribution, state of mixture and morphology of urban aerosol particles at given electrical mobilities,” J. Aerosol. Sci. 34, 1539–1553 (2003).
[CrossRef]

J. Heintzenberg, K. Okada, B. P. Luo, “The distribution of optical properties among atmospheric submicrometer particles of given electrical mobilities,” J. Geophys. Res. 107, 4107, doi: 10.1029/2001JD000372(2002).
[CrossRef]

J. Heintzenberg, A. Massling, W. Birmili, “The connection between hygroscopic and optical particle properties in the atmospheric aerosol,” Geophys. Res. Lett. 28, 3649–3651 (2001).
[CrossRef]

D. S. Covert, J. Heintzenberg, H.-C. Hansson, “Electro-optical detection of external mixtures in aerosols,” Aerosol Sci. Technol. 12, 446–456 (1990).
[CrossRef]

Hering, S. V.

S. V. Hering, P. H. McMurry, “Optical counter response to monodisperse atmospheric aerosols,” Atmos. Environ. 25A(2), 463–468 (1991).

Keil, A.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

Kerker, M.

M. Kerker, “Light scattering instrumentation for aerosol studies: an historical overview,” Aerosol Sci. Technol. 27, 522–540 (1997).
[CrossRef]

Koziar, C.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

Luo, B.

S. Borrmann, B. Luo, M. Mishchenko, “Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters,” J. Aerosol. Sci. 31, 789–799 (2000).
[CrossRef]

Luo, B. P.

J. Heintzenberg, K. Okada, B. P. Luo, “The distribution of optical properties among atmospheric submicrometer particles of given electrical mobilities,” J. Geophys. Res. 107, 4107, doi: 10.1029/2001JD000372(2002).
[CrossRef]

Massling, A.

J. Heintzenberg, A. Massling, W. Birmili, “The connection between hygroscopic and optical particle properties in the atmospheric aerosol,” Geophys. Res. Lett. 28, 3649–3651 (2001).
[CrossRef]

McMurry, P. H.

S. V. Hering, P. H. McMurry, “Optical counter response to monodisperse atmospheric aerosols,” Atmos. Environ. 25A(2), 463–468 (1991).

Mishchenko, M.

S. Borrmann, B. Luo, M. Mishchenko, “Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters,” J. Aerosol. Sci. 31, 789–799 (2000).
[CrossRef]

Mishchenko, M. I.

M. I. Mishchenko, L. D. Travis, “Capabilities and limitations of a current Fortran implementation of the T-matrix method for randomly oriented rotationally symmetric scatterers,” J. Quant. Spectrosc. Radiat. Transfer. 60, 309–324 (1998).
[CrossRef]

M. I. Mishchenko, “Light scattering by randomly oriented axially symmetric particles,” J. Opt. Soc. Am. A 8, 871–882 (1991).
[CrossRef]

Neusüß, C.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

Okada, K.

K. Okada, J. Heintzenberg, “Size distribution, state of mixture and morphology of urban aerosol particles at given electrical mobilities,” J. Aerosol. Sci. 34, 1539–1553 (2003).
[CrossRef]

J. Heintzenberg, K. Okada, B. P. Luo, “The distribution of optical properties among atmospheric submicrometer particles of given electrical mobilities,” J. Geophys. Res. 107, 4107, doi: 10.1029/2001JD000372(2002).
[CrossRef]

Pendleton, J. D.

R. G. Pinnick, J. D. Pendleton, G. Videen, “Response characteristics of the Particle Measuring Systems active scattering spectrometer probes,” Aerosol Sci. Technol. 33, 334–352 (2000).
[CrossRef]

Pinnick, R. G.

R. G. Pinnick, J. D. Pendleton, G. Videen, “Response characteristics of the Particle Measuring Systems active scattering spectrometer probes,” Aerosol Sci. Technol. 33, 334–352 (2000).
[CrossRef]

R. G. Pinnick, J. M. Rosen, “Response of Knollenberg light-scattering counters to non-spherical doublet polystyrene latex aerosols,” J. Aerosol. Sci. 10, 533–538 (1979).
[CrossRef]

Quinten, M.

M. Quinten, R. Friehmelt, K.-F. Ebert, “Sizing of aggregates of spheres by a white-light optical particle counter with 90° scattering angle,” J. Aerosol. Sci. 32, 63–72 (2001).
[CrossRef]

Ranz, W. E.

W. E. Ranz, J. B. Wong, “Impaction of dust and smoke particles on surface and body collectors,” Ind. Eng. Chem. 44, 1371–1381 (1952).
[CrossRef]

Rosen, J. M.

R. G. Pinnick, J. M. Rosen, “Response of Knollenberg light-scattering counters to non-spherical doublet polystyrene latex aerosols,” J. Aerosol. Sci. 10, 533–538 (1979).
[CrossRef]

Stratmann, F.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

W. Birmili, F. Stratmann, A. Wiedensohler, “Design of a DMA-based size spectrometer for a large particle size range and stable operation,” J. Aerosol. Sci. 30, 549–553 (1999).
[CrossRef]

Travis, L. D.

M. I. Mishchenko, L. D. Travis, “Capabilities and limitations of a current Fortran implementation of the T-matrix method for randomly oriented rotationally symmetric scatterers,” J. Quant. Spectrosc. Radiat. Transfer. 60, 309–324 (1998).
[CrossRef]

van de Hulst, H. C.

H. C. van de Hulst, Light Scattering by Small Particles (Wiley, New York, 1957).

Videen, G.

R. G. Pinnick, J. D. Pendleton, G. Videen, “Response characteristics of the Particle Measuring Systems active scattering spectrometer probes,” Aerosol Sci. Technol. 33, 334–352 (2000).
[CrossRef]

Wendisch, M.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

Wex, H.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

Wiedensohler, A.

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

W. Birmili, F. Stratmann, A. Wiedensohler, “Design of a DMA-based size spectrometer for a large particle size range and stable operation,” J. Aerosol. Sci. 30, 549–553 (1999).
[CrossRef]

Wong, J. B.

W. E. Ranz, J. B. Wong, “Impaction of dust and smoke particles on surface and body collectors,” Ind. Eng. Chem. 44, 1371–1381 (1952).
[CrossRef]

Aerosol Sci. Technol. (3)

D. S. Covert, J. Heintzenberg, H.-C. Hansson, “Electro-optical detection of external mixtures in aerosols,” Aerosol Sci. Technol. 12, 446–456 (1990).
[CrossRef]

M. Kerker, “Light scattering instrumentation for aerosol studies: an historical overview,” Aerosol Sci. Technol. 27, 522–540 (1997).
[CrossRef]

R. G. Pinnick, J. D. Pendleton, G. Videen, “Response characteristics of the Particle Measuring Systems active scattering spectrometer probes,” Aerosol Sci. Technol. 33, 334–352 (2000).
[CrossRef]

Atmos. Environ. (1)

S. V. Hering, P. H. McMurry, “Optical counter response to monodisperse atmospheric aerosols,” Atmos. Environ. 25A(2), 463–468 (1991).

Geophys. Res. Lett. (1)

J. Heintzenberg, A. Massling, W. Birmili, “The connection between hygroscopic and optical particle properties in the atmospheric aerosol,” Geophys. Res. Lett. 28, 3649–3651 (2001).
[CrossRef]

Ind. Eng. Chem. (1)

W. E. Ranz, J. B. Wong, “Impaction of dust and smoke particles on surface and body collectors,” Ind. Eng. Chem. 44, 1371–1381 (1952).
[CrossRef]

J. Aerosol. Sci. (5)

K. Okada, J. Heintzenberg, “Size distribution, state of mixture and morphology of urban aerosol particles at given electrical mobilities,” J. Aerosol. Sci. 34, 1539–1553 (2003).
[CrossRef]

W. Birmili, F. Stratmann, A. Wiedensohler, “Design of a DMA-based size spectrometer for a large particle size range and stable operation,” J. Aerosol. Sci. 30, 549–553 (1999).
[CrossRef]

R. G. Pinnick, J. M. Rosen, “Response of Knollenberg light-scattering counters to non-spherical doublet polystyrene latex aerosols,” J. Aerosol. Sci. 10, 533–538 (1979).
[CrossRef]

M. Quinten, R. Friehmelt, K.-F. Ebert, “Sizing of aggregates of spheres by a white-light optical particle counter with 90° scattering angle,” J. Aerosol. Sci. 32, 63–72 (2001).
[CrossRef]

S. Borrmann, B. Luo, M. Mishchenko, “Application of the T-matrix method to the measurement of aspherical (ellipsoidal) particles with forward scattering optical particle counters,” J. Aerosol. Sci. 31, 789–799 (2000).
[CrossRef]

J. Geophys. Res. (2)

J. Heintzenberg, K. Okada, B. P. Luo, “The distribution of optical properties among atmospheric submicrometer particles of given electrical mobilities,” J. Geophys. Res. 107, 4107, doi: 10.1029/2001JD000372(2002).
[CrossRef]

H. Wex, C. Neusüß, M. Wendisch, F. Stratmann, C. Koziar, A. Keil, A. Wiedensohler, M. Ebert, “Particle scattering, backscattering, and absorption coefficients: an in-situ closure and sensitivity study,” J. Geophys. Res. 107, 8122, doi: 10.1029/2000JD000234(2002).
[CrossRef]

J. Opt. Soc. Am. A (1)

J. Quant. Spectrosc. Radiat. Transfer. (1)

M. I. Mishchenko, L. D. Travis, “Capabilities and limitations of a current Fortran implementation of the T-matrix method for randomly oriented rotationally symmetric scatterers,” J. Quant. Spectrosc. Radiat. Transfer. 60, 309–324 (1998).
[CrossRef]

Phys. Rev. B. (1)

J. M. Gérardy, M. Ausloos, “Absorption spectrum of clusters of spheres from the general solution of Maxwell’s equations,” Phys. Rev. B. 25, 4204–4210 (1982).
[CrossRef]

Tellus (1)

G. Hänel, “The real part of the mean complex refractive index and the mean density of samples of atmospheric aerosol particles,” Tellus 20, 371–379 (1968).
[CrossRef]

Other (1)

H. C. van de Hulst, Light Scattering by Small Particles (Wiley, New York, 1957).

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Figures (4)

Fig. 1
Fig. 1

Average spread of simulated OPC signals over the OPC PHA channels for the ten classified particle types in samples M1–M3 (cf. Table 1).

Fig. 2
Fig. 2

Schematic picture of experimental and modeling tools of the present study. OPC = Optical Particle Counter; TEM = Transmission Electron Microscope.

Fig. 3
Fig. 3

Measured OPC spectra for the three urban aerosol samples M1–M3 in Table 1 with corresponding average model spectra. Pulse height analyzer channels are marked on the abscissa. On the logarithmic ordinate the OPC spectra are plotted, normalized to one particle each.

Fig. 4
Fig. 4

Retrieved distribution of volume-averaged imaginary parts mi = 0, 0.05, 0.1, and 0.5 of refractive index for the ten classified particle types in sample M1 (cf. Table 1).

Tables (2)

Tables Icon

Table 1 Sample Informationa

Tables Icon

Table 2 Number Fractions in Percent of the Ten Classified Particle Types in Samples M1-M3a

Equations (5)

Equations on this page are rendered with MathJax. Learn more.

PFp=i=13Pc,i-Pm,iPm,i2,
For R>MS=2πR2+RMesin-1e=4πrs2, For R<MS=π2M2+R2eln1+e1-e=4πrs2.
For R>Me=1-R2M21/2; For R<Me=1-M2R21/2.
RI=θmax,iθmax,isin θfθdθk=1NG ωk sin θkfθk.
PFo=i=1NCSc,i-Sm,iSm,i2

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