Abstract

We report a new method for automated identification and measurement of primary particles within soot aggregates as well as the sizes of the aggregates and discuss its application to high-resolution transmission electron microscope (TEM) images of the aggregates. The image processing algorithm is based on an optimized Hough transform, applied to the external border of the aggregate. This achieves a significant data reduction by decomposing the particle border into fragments, which are assumed to be spheres in the present application, consistent with the known morphology of soot aggregates. Unlike traditional techniques, which are ultimately reliant on manual (human) measurement of a small sample of primary particles from a subset of aggregates, this method gives a direct measurement of the sizes of the aggregates and the size distributions of the primary particles of which they are composed. The current version of the algorithm allows processing of high-resolution TEM images by a conventional laptop computer at a rate of 1–2 ms per aggregate. The results were validated by comparison with manual image processing, and excellent agreement was found.

© 2012 Optical Society of America

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  1. S. K. Satheesh and K. K. Moorthy, “Radiative effects of natural aerosols: a review,” Atmos. Environ. 39, 2089–2110 (2005).
    [CrossRef]
  2. M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
    [CrossRef]
  3. A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
    [CrossRef]
  4. S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
    [CrossRef]
  5. M. Lapuerta, R. Ballesteros, and F. J. Martos, “The effect of diesel engine conditions on the size and morphology of soot particles,” Int. J. Veh. Des. 50, 91–106 (2009).
    [CrossRef]
  6. M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
    [CrossRef]
  7. P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.
  8. N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
    [CrossRef]
  9. Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
    [CrossRef]
  10. R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
    [CrossRef]
  11. A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
    [CrossRef]
  12. O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
    [CrossRef]
  13. R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
    [CrossRef]
  14. C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
    [CrossRef]
  15. E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
    [CrossRef]
  16. C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
    [CrossRef]
  17. A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
    [CrossRef]
  18. S. Suzuki, K. Kuwana, and R. Dobashi, “Effect of particle morphology on thermophoretic velocity of aggregated soot particles,” Int. J. Heat Mass Trans. 52, 4695–4700 (2009).
    [CrossRef]
  19. M. M. Maricq, “Bipolar diffusion charging of soot aggregates,” Aerosol Sci. Technol. 42, 247–254 (2008).
    [CrossRef]
  20. J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
    [CrossRef]
  21. B. Hu, B. Yang, and U. O. Koylu, “Soot measurements at the axis of an ethylene/air nonpremixed turbulent jet flame,” Combust. Flame 134, 93–106 (2003).
    [CrossRef]
  22. K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
    [CrossRef]
  23. B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
    [CrossRef]
  24. C. H. Luo, W. M. Lee, and J. J. Liaw, “Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer,” J. Environ. Sci. China 21, 452–457 (2009).
    [CrossRef]
  25. A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
    [CrossRef]
  26. A. M. Brasil, T. L. Farias, and M. G. Carvalho, “A recipe for image characterization of fractal-like aggregates,” J. Aerosol Sci. 30, 1379–1389 (1999).
    [CrossRef]
  27. U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
    [CrossRef]
  28. R. J. Samson, G. W. Mulholland, and J. W. Gentry, “Structural analysis of soot agglomerates,” Langmuir 3, 272–281(1987).
    [CrossRef]
  29. O. L. Gulder, D. R. Snelling, and R. A. Sawchuk, “Influence of hydrogen addition to fuel on temperature field and soot formation in diffusion flames,” in Twenty-Sixth Symposium (International) on Combustion (Elsevier, 1996), Vol. 26, pp. 2351–2358.
  30. P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).
  31. N. Otsu, “A threshold selection method from gray-level histogram,” IEEE Trans. Syst. Man Cybern. SMC-9, 62–66 (1979).
  32. J. N. Kapur, P. K. Sahoo, and A. K. C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Comput. Vis. Graph. Image Proc. 29, 273–285 (1985).
    [CrossRef]
  33. J. P. Serra, Image Analysis and Mathematical Morphology (Academic, 1982).
  34. E. R. Davies, Machine Vision (Elsevier, 2005).
  35. I. Pitas, Digital Image Processing Algorithms (Prentice-Hall, 1993).
  36. P. V. C. Hough, “Method and means for recognizing complex patterns,” U.S. patent 3,069,654 (18December1962).
  37. R. O. Duda and P. E. Hart, “Use of the Hough transform to detect lines and curves on pictures,” Commun. ACM 15, 11–15 (1972).
    [CrossRef]
  38. V. F. Leavers, “Which Hough transform?” CVGIP Image Understand. 58, 250–264 (1993).
    [CrossRef]
  39. H. W. Li, M. A. Lavin, and R. J. Lemaster, “Fast Hough transform—a hierarchical approach,” Comput. Vision Graph. Image Proc. 36, 139–161 (1986).
    [CrossRef]
  40. D. H. Ballard, “Generalizing the Hough transform to detect arbitrary shapes,” Pattern Recogn. 13, 111–122 (1981).
    [CrossRef]
  41. R. S. Stephens, “Probabilistic approach to the Hough transform,” Image Vis. Comput. 9, 66–71 (1991).
    [CrossRef]
  42. L. Xu and E. Oja, “Randomized Hough transform (RHT): basic mechanisms, algorithms, and computational complexities,” CVGIP Image Understand. 57, 131–154 (1993).
    [CrossRef]
  43. S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
    [CrossRef]
  44. J. Tian and K. K. Ma, “A survey on super-resolution imaging,” Signal Image Video Process. 5, 329–342 (2011).
    [CrossRef]
  45. R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
    [CrossRef]

2011

J. Tian and K. K. Ma, “A survey on super-resolution imaging,” Signal Image Video Process. 5, 329–342 (2011).
[CrossRef]

2010

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
[CrossRef]

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

2009

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

S. Suzuki, K. Kuwana, and R. Dobashi, “Effect of particle morphology on thermophoretic velocity of aggregated soot particles,” Int. J. Heat Mass Trans. 52, 4695–4700 (2009).
[CrossRef]

N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
[CrossRef]

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

M. Lapuerta, R. Ballesteros, and F. J. Martos, “The effect of diesel engine conditions on the size and morphology of soot particles,” Int. J. Veh. Des. 50, 91–106 (2009).
[CrossRef]

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
[CrossRef]

C. H. Luo, W. M. Lee, and J. J. Liaw, “Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer,” J. Environ. Sci. China 21, 452–457 (2009).
[CrossRef]

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

2008

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
[CrossRef]

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

M. M. Maricq, “Bipolar diffusion charging of soot aggregates,” Aerosol Sci. Technol. 42, 247–254 (2008).
[CrossRef]

2007

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

2005

S. K. Satheesh and K. K. Moorthy, “Radiative effects of natural aerosols: a review,” Atmos. Environ. 39, 2089–2110 (2005).
[CrossRef]

2004

A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
[CrossRef]

2003

B. Hu, B. Yang, and U. O. Koylu, “Soot measurements at the axis of an ethylene/air nonpremixed turbulent jet flame,” Combust. Flame 134, 93–106 (2003).
[CrossRef]

2001

P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).

1999

A. M. Brasil, T. L. Farias, and M. G. Carvalho, “A recipe for image characterization of fractal-like aggregates,” J. Aerosol Sci. 30, 1379–1389 (1999).
[CrossRef]

1995

U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
[CrossRef]

1993

V. F. Leavers, “Which Hough transform?” CVGIP Image Understand. 58, 250–264 (1993).
[CrossRef]

L. Xu and E. Oja, “Randomized Hough transform (RHT): basic mechanisms, algorithms, and computational complexities,” CVGIP Image Understand. 57, 131–154 (1993).
[CrossRef]

1991

R. S. Stephens, “Probabilistic approach to the Hough transform,” Image Vis. Comput. 9, 66–71 (1991).
[CrossRef]

1987

R. J. Samson, G. W. Mulholland, and J. W. Gentry, “Structural analysis of soot agglomerates,” Langmuir 3, 272–281(1987).
[CrossRef]

1986

H. W. Li, M. A. Lavin, and R. J. Lemaster, “Fast Hough transform—a hierarchical approach,” Comput. Vision Graph. Image Proc. 36, 139–161 (1986).
[CrossRef]

1985

J. N. Kapur, P. K. Sahoo, and A. K. C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Comput. Vis. Graph. Image Proc. 29, 273–285 (1985).
[CrossRef]

1981

D. H. Ballard, “Generalizing the Hough transform to detect arbitrary shapes,” Pattern Recogn. 13, 111–122 (1981).
[CrossRef]

1979

N. Otsu, “A threshold selection method from gray-level histogram,” IEEE Trans. Syst. Man Cybern. SMC-9, 62–66 (1979).

1972

R. O. Duda and P. E. Hart, “Use of the Hough transform to detect lines and curves on pictures,” Commun. ACM 15, 11–15 (1972).
[CrossRef]

Adelhelm, C.

C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
[CrossRef]

Ahern, A.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Arnott, W. P.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

Asbach, C.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Ballard, D. H.

D. H. Ballard, “Generalizing the Hough transform to detect arbitrary shapes,” Pattern Recogn. 13, 111–122 (1981).
[CrossRef]

Ballesteros, R.

M. Lapuerta, R. Ballesteros, and F. J. Martos, “The effect of diesel engine conditions on the size and morphology of soot particles,” Int. J. Veh. Des. 50, 91–106 (2009).
[CrossRef]

Barfield, P.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

Beck, L.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

Boogaard, H.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Brasil, A. M.

A. M. Brasil, T. L. Farias, and M. G. Carvalho, “A recipe for image characterization of fractal-like aggregates,” J. Aerosol Sci. 30, 1379–1389 (1999).
[CrossRef]

Brem, B.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Brown, R. C.

P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.

Brunekreef, B.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Cappa, C. D.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Carrico, C. M.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Carvalho, M. G.

A. M. Brasil, T. L. Farias, and M. G. Carvalho, “A recipe for image characterization of fractal-like aggregates,” J. Aerosol Sci. 30, 1379–1389 (1999).
[CrossRef]

U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
[CrossRef]

Chakrabarty, R. K.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

Chen,

P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).

Choi, S. C.

S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
[CrossRef]

Chung, P.-C.

P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).

Chung, T.-S.

P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).

Clarke, A.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Cross, E. S.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Dahmann, D.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Dakhel, P. M.

P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.

Davidovits, P.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Davies, E. R.

E. R. Davies, Machine Vision (Elsevier, 2005).

DeMott, P. J.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

Dethloff, K.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Dobashi, R.

S. Suzuki, K. Kuwana, and R. Dobashi, “Effect of particle morphology on thermophoretic velocity of aggregated soot particles,” Int. J. Heat Mass Trans. 52, 4695–4700 (2009).
[CrossRef]

Dong, Y. J.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

Dubey, M.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Duda, R. O.

R. O. Duda and P. E. Hart, “Use of the Hough transform to detect lines and curves on pictures,” Commun. ACM 15, 11–15 (1972).
[CrossRef]

Dutton, E. G.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Faeth, G. M.

U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
[CrossRef]

Fahey, D. W.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Farias, T. L.

A. M. Brasil, T. L. Farias, and M. G. Carvalho, “A recipe for image characterization of fractal-like aggregates,” J. Aerosol Sci. 30, 1379–1389 (1999).
[CrossRef]

U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
[CrossRef]

Fissan, H.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Freedman, A.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Freitag, S.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Garro, M. A.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

Gentry, J. W.

R. J. Samson, G. W. Mulholland, and J. W. Gentry, “Structural analysis of soot agglomerates,” Langmuir 3, 272–281(1987).
[CrossRef]

Gulder, O. L.

O. L. Gulder, D. R. Snelling, and R. A. Sawchuk, “Influence of hydrogen addition to fuel on temperature field and soot formation in diffusion flames,” in Twenty-Sixth Symposium (International) on Combustion (Elsevier, 1996), Vol. 26, pp. 2351–2358.

Guo, S. Y.

S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
[CrossRef]

Han, J. H.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Hart, P. E.

R. O. Duda and P. E. Hart, “Use of the Hough transform to detect lines and curves on pictures,” Commun. ACM 15, 11–15 (1972).
[CrossRef]

Hasegawa, S.

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

Hayashi, M.

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

Hays, M. D.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

Henning, S.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Herber, A.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Herrmann, F.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Hoek, G.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Hough, P. V. C.

P. V. C. Hough, “Method and means for recognizing complex patterns,” U.S. patent 3,069,654 (18December1962).

Hu, B.

B. Hu, B. Yang, and U. O. Koylu, “Soot measurements at the axis of an ethylene/air nonpremixed turbulent jet flame,” Combust. Flame 134, 93–106 (2003).
[CrossRef]

Jayne, J. T.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Ji, H. Z.

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

Kaminski, H.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Kapur, J. N.

J. N. Kapur, P. K. Sahoo, and A. K. C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Comput. Vis. Graph. Image Proc. 29, 273–285 (1985).
[CrossRef]

Karcher, B.

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

Keskinen, J.

A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
[CrossRef]

Khalizov, A. F.

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Khokhlova, T. D.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Kiendler-Scharr, A.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Kiesling, H. J.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Kireeva, E. D.

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Kiselev, A.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Koehler, K. A.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Koike, M.

N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
[CrossRef]

Kok, G.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Kolb, C. E.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Kolucki, J.

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Kondo, Y.

N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
[CrossRef]

Kong, Y. G.

S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
[CrossRef]

Koylu, U. O.

B. Hu, B. Yang, and U. O. Koylu, “Soot measurements at the axis of an ethylene/air nonpremixed turbulent jet flame,” Combust. Flame 134, 93–106 (2003).
[CrossRef]

U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
[CrossRef]

Kreidenweis, S. M.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Kuhlbusch, T. A. J.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Kuwana, K.

S. Suzuki, K. Kuwana, and R. Dobashi, “Effect of particle morphology on thermophoretic velocity of aggregated soot particles,” Int. J. Heat Mass Trans. 52, 4695–4700 (2009).
[CrossRef]

Lack, D. A.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Lampert, A.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Lapuerta, M.

M. Lapuerta, R. Ballesteros, and F. J. Martos, “The effect of diesel engine conditions on the size and morphology of soot particles,” Int. J. Veh. Des. 50, 91–106 (2009).
[CrossRef]

Lavin, M. A.

H. W. Li, M. A. Lavin, and R. J. Lemaster, “Fast Hough transform—a hierarchical approach,” Comput. Vision Graph. Image Proc. 36, 139–161 (1986).
[CrossRef]

Lavrich, R. J.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

Leavers, V. F.

V. F. Leavers, “Which Hough transform?” CVGIP Image Understand. 58, 250–264 (1993).
[CrossRef]

Lee, C. S.

S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
[CrossRef]

Lee, K. S.

S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
[CrossRef]

Lee, W. M.

C. H. Luo, W. M. Lee, and J. J. Liaw, “Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer,” J. Environ. Sci. China 21, 452–457 (2009).
[CrossRef]

Lemaster, R. J.

H. W. Li, M. A. Lavin, and R. J. Lemaster, “Fast Hough transform—a hierarchical approach,” Comput. Vision Graph. Image Proc. 36, 139–161 (1986).
[CrossRef]

Letzel, T.

C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
[CrossRef]

Li, H. W.

H. W. Li, M. A. Lavin, and R. J. Lemaster, “Fast Hough transform—a hierarchical approach,” Comput. Vision Graph. Image Proc. 36, 139–161 (1986).
[CrossRef]

Li, S. M.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Liao, P. S.

P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).

Liaw, J. J.

C. H. Luo, W. M. Lee, and J. J. Liaw, “Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer,” J. Environ. Sci. China 21, 452–457 (2009).
[CrossRef]

Lieberwirth, I.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Liu, P. S. K.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Lukachko, S. P.

P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.

Luo, C. H.

C. H. Luo, W. M. Lee, and J. J. Liaw, “Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer,” J. Environ. Sci. China 21, 452–457 (2009).
[CrossRef]

Lupi, A.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Ma, K. K.

J. Tian and K. K. Ma, “A survey on super-resolution imaging,” Signal Image Video Process. 5, 329–342 (2011).
[CrossRef]

Maricq, M. M.

M. M. Maricq, “Bipolar diffusion charging of soot aggregates,” Aerosol Sci. Technol. 42, 247–254 (2008).
[CrossRef]

Marr, L. C.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Martos, F. J.

M. Lapuerta, R. Ballesteros, and F. J. Martos, “The effect of diesel engine conditions on the size and morphology of soot particles,” Int. J. Veh. Des. 50, 91–106 (2009).
[CrossRef]

Massoli, P.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Maturilli, M.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Mazzola, M.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Mazzoleni, C.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

McMurry, P. H.

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Meliefste, K.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Mentel, T. F.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Miake-Lye, R. C.

P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.

Mogil’nikov, V. P.

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

Mohler, O.

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

Monz, C.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Moorthy, K. K.

S. K. Satheesh and K. K. Moorthy, “Radiative effects of natural aerosols: a review,” Atmos. Environ. 39, 2089–2110 (2005).
[CrossRef]

Moosmuller, H.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

Mulholland, G. W.

R. J. Samson, G. W. Mulholland, and J. W. Gentry, “Structural analysis of soot agglomerates,” Langmuir 3, 272–281(1987).
[CrossRef]

Mulhopt, S.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Neuber, R.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Ng, N. L.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Niessner, R.

C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
[CrossRef]

Oja, E.

L. Xu and E. Oja, “Randomized Hough transform (RHT): basic mechanisms, algorithms, and computational complexities,” CVGIP Image Understand. 57, 131–154 (1993).
[CrossRef]

Oldenwening, M.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Olfert, J.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Onasch, T. B.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Oshima, N.

N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
[CrossRef]

Otsu, N.

N. Otsu, “A threshold selection method from gray-level histogram,” IEEE Trans. Syst. Man Cybern. SMC-9, 62–66 (1979).

Pagels, J.

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Paur, H. R.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Pechtl, S.

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

Petters, M. D.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Pitas, I.

I. Pitas, Digital Image Processing Algorithms (Prentice-Hall, 1993).

Popovicheva, O. B.

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Poschl, U.

C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
[CrossRef]

Pridmore, T.

S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
[CrossRef]

Ristimaki, J. M.

A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
[CrossRef]

Ritter, C.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Roh, H. G.

S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
[CrossRef]

Sahoo, P. K.

J. N. Kapur, P. K. Sahoo, and A. K. C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Comput. Vis. Graph. Image Proc. 29, 273–285 (1985).
[CrossRef]

Samson, R. J.

R. J. Samson, G. W. Mulholland, and J. W. Gentry, “Structural analysis of soot agglomerates,” Langmuir 3, 272–281(1987).
[CrossRef]

Satheesh, S. K.

S. K. Satheesh and K. K. Moorthy, “Radiative effects of natural aerosols: a review,” Atmos. Environ. 39, 2089–2110 (2005).
[CrossRef]

Sawchuk, R. A.

O. L. Gulder, D. R. Snelling, and R. A. Sawchuk, “Influence of hydrogen addition to fuel on temperature field and soot formation in diffusion flames,” in Twenty-Sixth Symposium (International) on Combustion (Elsevier, 1996), Vol. 26, pp. 2351–2358.

Schneider, J.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Schnell, R. C.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Schwarz, J. P.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Sedlacek, A.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Serra, J. P.

J. P. Serra, Image Analysis and Mathematical Morphology (Academic, 1982).

Shi, Z. B.

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

Shonija, N. K.

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Slowik, J. G.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Snelling, D. R.

O. L. Gulder, D. R. Snelling, and R. A. Sawchuk, “Influence of hydrogen addition to fuel on temperature field and soot formation in diffusion flames,” in Twenty-Sixth Symposium (International) on Combustion (Elsevier, 1996), Vol. 26, pp. 2351–2358.

Spackman, J. R.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Stephens, R. S.

R. S. Stephens, “Probabilistic approach to the Hough transform,” Image Vis. Comput. 9, 66–71 (1991).
[CrossRef]

Stock, M.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Stone, R. S.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Strak, M.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Stratmann, F.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Subramanian, R.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Suzuki, S.

S. Suzuki, K. Kuwana, and R. Dobashi, “Effect of particle morphology on thermophoretic velocity of aggregated soot particles,” Int. J. Heat Mass Trans. 52, 4695–4700 (2009).
[CrossRef]

Thornhill, D.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Tian, G. X.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

Tian, J.

J. Tian and K. K. Ma, “A survey on super-resolution imaging,” Signal Image Video Process. 5, 329–342 (2011).
[CrossRef]

Timofeev, M. A.

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

Trimborn, A.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Vaaraslahti, K. M.

A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
[CrossRef]

Vander Wal, R. L.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

Virtanen, A. K. K.

A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
[CrossRef]

Vitale, V.

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

Voetz, M.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

Waitz, I. A.

P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.

Walter, S.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Wang, L.

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

Wennrich, C.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Wex, H.

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

Williams, L. R.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Wong, A. K. C.

J. N. Kapur, P. K. Sahoo, and A. K. C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Comput. Vis. Graph. Image Proc. 29, 273–285 (1985).
[CrossRef]

Worsnop, D. R.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Wrobel, W.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

Xu, L.

L. Xu and E. Oja, “Randomized Hough transform (RHT): basic mechanisms, algorithms, and computational complexities,” CVGIP Image Understand. 57, 131–154 (1993).
[CrossRef]

Xue, H. X.

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Yang, B.

B. Hu, B. Yang, and U. O. Koylu, “Soot measurements at the axis of an ethylene/air nonpremixed turbulent jet flame,” Combust. Flame 134, 93–106 (2003).
[CrossRef]

Yu, F.

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

Zhang, D.

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Zhang, D. Z.

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

Zhang, M.

S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
[CrossRef]

Zhang, R. Y.

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Zhang, Y.

N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
[CrossRef]

Zheng, J.

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

Zuurbier, M.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Aerosol Sci. Technol.

E. S. Cross, T. B. Onasch, A. Ahern, W. Wrobel, J. G. Slowik, J. Olfert, D. A. Lack, P. Massoli, C. D. Cappa, J. P. Schwarz, J. R. Spackman, D. W. Fahey, A. Sedlacek, A. Trimborn, J. T. Jayne, A. Freedman, L. R. Williams, N. L. Ng, C. Mazzoleni, M. Dubey, B. Brem, G. Kok, R. Subramanian, S. Freitag, A. Clarke, D. Thornhill, L. C. Marr, C. E. Kolb, D. R. Worsnop, and P. Davidovits, “Soot particle studies instrument inter-comparison project overview,” Aerosol Sci. Technol. 44, 592–611 (2010).
[CrossRef]

M. M. Maricq, “Bipolar diffusion charging of soot aggregates,” Aerosol Sci. Technol. 42, 247–254 (2008).
[CrossRef]

J. G. Slowik, E. S. Cross, J. H. Han, J. Kolucki, P. Davidovits, L. R. Williams, T. B. Onasch, J. T. Jayne, C. E. Kolb, and D. R. Worsnop, “Measurements of morphology changes of fractal soot particles using coating and denuding experiments: implications for optical absorption and atmospheric lifetime,” Aerosol Sci. Technol. 41, 734–750 (2007).
[CrossRef]

Analyt. Bioanalyt. Chem.

C. Adelhelm, R. Niessner, U. Poschl, and T. Letzel, “Analysis of large oxygenated and nitrated polycyclic aromatic hydrocarbons formed under simulated diesel engine exhaust conditions (by compound fingerprints with SPE/LC-API-MS),” Analyt. Bioanalyt. Chem. 391, 2599–2608 (2008).
[CrossRef]

Atmos. Chem. Phys.

B. Karcher, O. Mohler, P. J. Demott, S. Pechtl, and F. Yu, “Insights into the role of soot aerosols in cirrus cloud formation,” Atmos. Chem. Phys. 7, 4203–4227 (2007).
[CrossRef]

Atmos. Environ.

S. K. Satheesh and K. K. Moorthy, “Radiative effects of natural aerosols: a review,” Atmos. Environ. 39, 2089–2110 (2005).
[CrossRef]

Combust. Flame

B. Hu, B. Yang, and U. O. Koylu, “Soot measurements at the axis of an ethylene/air nonpremixed turbulent jet flame,” Combust. Flame 134, 93–106 (2003).
[CrossRef]

U. O. Koylu, G. M. Faeth, T. L. Farias, and M. G. Carvalho, “Fractal and projected structure properties of soot aggregates,” Combust. Flame 100, 621–633 (1995).
[CrossRef]

Commun. ACM

R. O. Duda and P. E. Hart, “Use of the Hough transform to detect lines and curves on pictures,” Commun. ACM 15, 11–15 (1972).
[CrossRef]

Comput. Vis. Graph. Image Proc.

J. N. Kapur, P. K. Sahoo, and A. K. C. Wong, “A new method for gray-level picture thresholding using the entropy of the histogram,” Comput. Vis. Graph. Image Proc. 29, 273–285 (1985).
[CrossRef]

Comput. Vision Graph. Image Proc.

H. W. Li, M. A. Lavin, and R. J. Lemaster, “Fast Hough transform—a hierarchical approach,” Comput. Vision Graph. Image Proc. 36, 139–161 (1986).
[CrossRef]

CVGIP Image Understand.

V. F. Leavers, “Which Hough transform?” CVGIP Image Understand. 58, 250–264 (1993).
[CrossRef]

L. Xu and E. Oja, “Randomized Hough transform (RHT): basic mechanisms, algorithms, and computational complexities,” CVGIP Image Understand. 57, 131–154 (1993).
[CrossRef]

Energy Fuels

S. C. Choi, H. G. Roh, K. S. Lee, and C. S. Lee, “Effects of fuel injection parameters on the morphological characteristics of soot particulates and exhaust emissions from a light-duty diesel engine,” Energy Fuels 24, 2875–2882 (2010).
[CrossRef]

Environ. Sci. Technol.

M. D. Hays, L. Beck, P. Barfield, R. J. Lavrich, Y. J. Dong, and R. L. Vander Wal, “Physical and chemical characterization of residential oil boiler emissions,” Environ. Sci. Technol. 42, 2496–2502 (2008).
[CrossRef]

A. K. K. Virtanen, J. M. Ristimaki, K. M. Vaaraslahti, and J. Keskinen, “Effect of engine load on diesel soot particles,” Environ. Sci. Technol. 38, 2551–2556 (2004).
[CrossRef]

IEEE Trans. Syst. Man Cybern.

N. Otsu, “A threshold selection method from gray-level histogram,” IEEE Trans. Syst. Man Cybern. SMC-9, 62–66 (1979).

Image Vis. Comput.

R. S. Stephens, “Probabilistic approach to the Hough transform,” Image Vis. Comput. 9, 66–71 (1991).
[CrossRef]

Int. J. Heat Mass Trans.

S. Suzuki, K. Kuwana, and R. Dobashi, “Effect of particle morphology on thermophoretic velocity of aggregated soot particles,” Int. J. Heat Mass Trans. 52, 4695–4700 (2009).
[CrossRef]

Int. J. Veh. Des.

M. Lapuerta, R. Ballesteros, and F. J. Martos, “The effect of diesel engine conditions on the size and morphology of soot particles,” Int. J. Veh. Des. 50, 91–106 (2009).
[CrossRef]

Izv. Atmos. Ocean. Phys.

O. B. Popovicheva, E. D. Kireeva, M. A. Timofeev, N. K. Shonija, and V. P. Mogil’nikov, “Carbonaceous aerosols of aviation and shipping emissions,” Izv. Atmos. Ocean. Phys. 46, 339–346 (2010).
[CrossRef]

J. Aerosol Sci.

A. M. Brasil, T. L. Farias, and M. G. Carvalho, “A recipe for image characterization of fractal-like aggregates,” J. Aerosol Sci. 30, 1379–1389 (1999).
[CrossRef]

J. Environ. Sci. China

C. H. Luo, W. M. Lee, and J. J. Liaw, “Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer,” J. Environ. Sci. China 21, 452–457 (2009).
[CrossRef]

J. Geophys. Res. Atmos.

A. F. Khalizov, R. Y. Zhang, D. Zhang, H. X. Xue, J. Pagels, and P. H. McMurry, “Formation of highly hygroscopic soot aerosols upon internal mixing with sulfuric acid vapor,” J. Geophys. Res. Atmos. 114, D05208 (2009).
[CrossRef]

R. S. Stone, A. Herber, V. Vitale, M. Mazzola, A. Lupi, R. C. Schnell, E. G. Dutton, P. S. K. Liu, S. M. Li, K. Dethloff, A. Lampert, C. Ritter, M. Stock, R. Neuber, and M. Maturilli, “A three-dimensional characterization of Arctic aerosols from airborne Sun photometer observations: PAM-ARCMIP, April 2009,” J. Geophys. Res. Atmos. 115, D13203 (2010).
[CrossRef]

A. Kiselev, C. Wennrich, F. Stratmann, H. Wex, S. Henning, T. F. Mentel, A. Kiendler-Scharr, J. Schneider, S. Walter, and I. Lieberwirth, “Morphological characterization of soot aerosol particles during LACIS Experiment in November (LExNo),” J. Geophys. Res. Atmos. 115, D11204 (2010).
[CrossRef]

N. Oshima, M. Koike, Y. Zhang, and Y. Kondo, “Aging of black carbon in outflow from anthropogenic sources using a mixing state resolved model: 2. Aerosol optical properties and cloud condensation nuclei activities,” J. Geophys. Res. Atmos. 114, D18202 (2009).
[CrossRef]

J. Inf. Sci. Eng.

P. S. Liao, Chen, T.-S. Chung, and P.-C. Chung, “A fast algorithm for multilevel thresholding,” J. Inf. Sci. Eng. 17, 713–727 (2001).

J. Nanopart. Res.

C. Asbach, H. Kaminski, H. Fissan, C. Monz, D. Dahmann, S. Mulhopt, H. R. Paur, H. J. Kiesling, F. Herrmann, M. Voetz, and T. A. J. Kuhlbusch, “Comparison of four mobility particle sizers with different time resolution for stationary exposure measurements,” J. Nanopart. Res. 11, 1593–1609 (2009).
[CrossRef]

J. Phys. Chem. A

A. F. Khalizov, H. X. Xue, L. Wang, J. Zheng, and R. Y. Zhang, “Enhanced light absorption and scattering by carbon soot aerosol internally mixed with sulfuric acid,” J. Phys. Chem. A 113, 1066–1074 (2009).
[CrossRef]

Langmuir

R. J. Samson, G. W. Mulholland, and J. W. Gentry, “Structural analysis of soot agglomerates,” Langmuir 3, 272–281(1987).
[CrossRef]

Occup. Environ. Med.

M. Strak, H. Boogaard, K. Meliefste, M. Oldenwening, M. Zuurbier, B. Brunekreef, and G. Hoek, “Respiratory health effects of ultrafine and fine particle exposure in cyclists,” Occup. Environ. Med. 67, 118–124 (2010).
[CrossRef]

Pattern Recogn.

D. H. Ballard, “Generalizing the Hough transform to detect arbitrary shapes,” Pattern Recogn. 13, 111–122 (1981).
[CrossRef]

Pattern Recogn. Lett.

S. Y. Guo, T. Pridmore, Y. G. Kong, and M. Zhang, “An improved Hough transform voting scheme utilizing surround suppression,” Pattern Recogn. Lett. 30, 1241–1252 (2009).
[CrossRef]

Phys. Chem. Chem. Phys.

K. A. Koehler, P. J. DeMott, S. M. Kreidenweis, O. B. Popovicheva, M. D. Petters, C. M. Carrico, E. D. Kireeva, T. D. Khokhlova, and N. K. Shonija, “Cloud condensation nuclei and ice nucleation activity of hydrophobic and hydrophilic soot particles,” Phys. Chem. Chem. Phys. 11, 7906–7920 (2009).
[CrossRef]

Phys. Rev. Lett.

R. K. Chakrabarty, H. Moosmuller, W. P. Arnott, M. A. Garro, G. X. Tian, J. G. Slowik, E. S. Cross, J. H. Han, P. Davidovits, T. B. Onasch, and D. R. Worsnop, “Low fractal dimension cluster-dilute soot aggregates from a premixed flame,” Phys. Rev. Lett. 102, 235504 (2009).
[CrossRef]

Proc. Natl. Acad. Sci. USA

R. Y. Zhang, A. F. Khalizov, J. Pagels, D. Zhang, H. X. Xue, and P. H. McMurry, “Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing,” Proc. Natl. Acad. Sci. USA 105, 10291–10296 (2008).
[CrossRef]

Sci. Total Environ.

Z. B. Shi, D. Z. Zhang, H. Z. Ji, S. Hasegawa, and M. Hayashi, “Modification of soot by volatile species in an urban atmosphere,” Sci. Total Environ. 389, 195–201 (2008).
[CrossRef]

Signal Image Video Process.

J. Tian and K. K. Ma, “A survey on super-resolution imaging,” Signal Image Video Process. 5, 329–342 (2011).
[CrossRef]

Other

P. M. Dakhel, S. P. Lukachko, R. C. Miake-Lye, R. C. Brown, and I. A. Waitz, “Post-combustion evolution of soot properties in an aircraft engine,” in Proceedings of GT2005: ASME Turbo Expo 2005 (ASME, 2005), Vol. 2, pp. 787–795.

O. L. Gulder, D. R. Snelling, and R. A. Sawchuk, “Influence of hydrogen addition to fuel on temperature field and soot formation in diffusion flames,” in Twenty-Sixth Symposium (International) on Combustion (Elsevier, 1996), Vol. 26, pp. 2351–2358.

J. P. Serra, Image Analysis and Mathematical Morphology (Academic, 1982).

E. R. Davies, Machine Vision (Elsevier, 2005).

I. Pitas, Digital Image Processing Algorithms (Prentice-Hall, 1993).

P. V. C. Hough, “Method and means for recognizing complex patterns,” U.S. patent 3,069,654 (18December1962).

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Figures (13)

Fig. 1.
Fig. 1.

Examples of TEM images: (a) from data array A, magnification 1.62 nm / pixel and (b) from data array B , magnification 0.63 nm / pixel . The aggregate in the white box is used to demonstrate the image processing methods.

Fig. 2.
Fig. 2.

Intensity histogram of the aggregate image selected in Fig. 1(b). A pixel value of zero corresponds to black; the peak at about 160 represents the most common background intensity value.

Fig. 3.
Fig. 3.

Circular structural elements used for the smoothing operator: 5 × 5 , 6 × 6 , and 7 × 7 pixel size.

Fig. 4.
Fig. 4.

(a) Output of Otsu thresholding. (b) Same after morphological smoothing and removal of border aggregates.

Fig. 5.
Fig. 5.

Size distribution of primary particles retrieved using different smoothing elements.

Fig. 6.
Fig. 6.

(Color online) (a) Outline of the aggregate, computed by Papert turtle algorithm and (b) same aggregate after edge vectorization.

Fig. 7.
Fig. 7.

(Color online) Straightforward Hough transform of the particle’s border.

Fig. 8.
Fig. 8.

(Color online) Result shown in Fig. 7, after regularization of the Hough transform, overlaid on the original TEM image.

Fig. 9.
Fig. 9.

Comparison of particles from the low-resolution dataset ( A ), measured by the automated method (blue circles) and by a human observer (green circles). The red curve outlines the border of the aggregate. The size of the black marker is 20 pixels (32 nm).

Fig. 10.
Fig. 10.

Comparison of manual and automated measurements of the primary particle radii.

Fig. 11.
Fig. 11.

Automated measurements of the size distributions of primary particles in images with resolution 1.62 nm / pixel ( 5600 × —image array A ) and 0.63 nm / pixel (17,000 × —image array B ).

Fig. 12.
Fig. 12.

Number of primary particles as a projected area ratio.

Fig. 13.
Fig. 13.

Ratio of maximum dimension to the radius of gyration of the aggregate for data array A .

Tables (3)

Tables Icon

Table 1. Comparison of Automatic and Manual Processing (Image 50mm-A3-5600X.0134) a

Tables Icon

Table 2. Comparison of Automatic and Manual Processing (Image 50mm-A3-5600X.0133) a

Tables Icon

Table 3. Comparison of Automatic and Manual Processing (Image 50mm-A3-5600X.0134) a

Equations (4)

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

N = k ( R g a ) D ,
N = ( A aggregate A monomer ) α ,
A monomer = π a 2 ,
L max / 2 R g ,

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