Ultrafine particles aerosol

Tippe AH, U. Roth, C. (2002) Deposition of fine and ultrafine aerosol particles during exposure at the air/cell interface. J Aerosol Sci 207-218... 

Carson, P. G., M. V. Johnston, and A. S. Wexler, Laser Desorp-tion/Ionization of Ultrafine Aerosol Particles, Rapid Commun. Mass Spectrosc., 11, 993-996 (1997b). 

B. Karcher, F. Yu, F. P. Schroder and R. P. Turco, Ultrafine aerosol particles in aircraft plumes Analysis... 

Kumar P, Fennell P, Symonds J, Britter R (2008) Treatment of losses of ultrafine aerosol particles in long sampling tubes during ambient measurements. Atmos Environ... 

Carson PG, Johnston MV, Wexler AS (1997) Laser desorption/ionization of ultrafine aerosol particles. Rapid CommunMass Spectrom 11 993-996... 

Ma kela JM, Aalto P, Jokinen V, Pohja T, Nissinen A, Palmroth S, Markkanen T, Seitsonen K, Lihavainen H, Kulmala M (1997) Observations of ultrafine aerosol particle formation and growth in boreal forest. Geophys Res Lett 24 1219-1222... 

Schmidt-Ott, A. (1988). In-situ measurement of the fractal dimensionality of ultrafine aerosol particles. A/ / /. Phys. Lett., 52, 954—956. 

Kittleson DB. Engines and nanoparticles a review. J Aerosol Sci 1998 29(6) 575-88. Maynard AD, et al. Examining elemental surface enrichment in ultrafine aerosol particles using analytical scanning transmission electron microscopy. Aerosol Sci Technol 2004 38(4) 365-81. 

Schiller, C.F., Gebhart, J., Heder, J., Rudolf, G., and Stahlhofen.W. (1986). Factors influencing total deposition of ultrafine aerosol particles in the human respiratory tract. Journal of Aerosol Sdence, Vol. 17, pp. 328-332. 

Y. Kousaka, K. Okuyama, and T. Mimura, Diffusion on electrical classification of ultrafine aerosol-particles in differential mobility analyzer, J. Chem. Eng. Japan 19, 401M07, 1986. 

Thus, there is a size threshold that must be reached before a cluster of atoms becomes big enough to be detected and turns into a "condensation nuclei". Recent work by Madelaine and coworkers (Perrin, et al, 1978 Madelaine, et al., 1980) have extended the size of measurable ultrafine particles to the order of 0.003 ym. They find rapid coagulation of this ultrafine aerosol to a larger average diameter one that is easily observable. 

In a similar study, Allen and co-workers (1996) determined the particle size distribution for 15 PAHs with molecular weights ranging from 178 (e.g., phenan-threne) to 300 (coronene) and associated with urban aerosols in Boston, Massachusetts. As for BaP in the winter (Venkataraman and Friedlander, 1994b), PAHs with MW >228 were primarily present in the fine aerosol fraction (Dp < 2 /Am). A study of 6-ring, MW 302 PAH at the same site showed bimodal distributions, with most of the mass in the 0.3- to 1.0-/zm particle size size range a smaller fraction was in the ultrafine mode particles (0.09-0.14 /xm) (Allen et al., 1998). For PAHs with MW 178—202, the compounds were approximately evenly distributed between the fine and coarse (D > 2 /am) fractions. Polycyclic aromatic hydrocarbons in size-segregated aerosols col-... 

Kotzick, R., U. Panne, and R. Niessner, Changes in Condensation Properties of Ultrafine Carbon Particles Subjected to Oxidation by Ozone, J. Aerosol Sci, 28, 725-735 (1997). 

Thus, while there are copious data showing that ultrafine aerosols nucleate in a wide range of situations (e.g., boundary layer air [3], cloud outflows [27], upper troposphere[31,32]), and that particle production is often coherent over regional scales, and not confined to local sources, the underlying nucleation processes have not yet been identified. An alternative explanation for some of these observations, outlined in the following sections, considers the role of background ionization in the generation of new particles in the troposphere [19,33]. 

Figure 1. Measured aircraft ultrafine aerosol emissions are compared with equivalent model predictions. The aerosol emission index (El) is given as the total number of particles generated for each kilogram of fuel burned, at particle sizes exceeding d>5 nm or d> 14 nm (open and filled symbols, respectively). Data were collected in the SULFUR-5 field campaign. In the simulations (lines), different initial chemiion concentrations, nio, were assumed, as indicated in the legend at the left of the figure (the first number is the value of n in /cmJ, and the second is the lower particle size cutoff diameter, nm. From [84],...

Chan, L. Y., and V. A. Mohnen, The formation of ultrafine ion H2O-H2SO4 aerosol particles through ion-... 

Birmili W, Weinhold K, Nordmann S et al (2009) Atmospheric aerosol measurements in the German ultrafine aerosol network (GUAN). Part 1. Soot and particle number size distributions. Gefahrst Reinhalt Luft 69 137-145... 

Notably, the instruments used in the European Supersites for Atmospheric Aerosol Research (EUSAAR)/Aerosols, Clouds, and Trace gases Research Infrastructure Network (ACTRIS) and German Ultrafine Aerosol Network (GUAN) measurements used in this chapter are from intercalibrated measurements, where the abilities of the instruments were determined in common intercalibration workshops [15]. Overall, the instruments agree well on particle sizes between 20 and 200 nm, with the differences above 200 nm still relatively minor for number concentrations. In smallest particles sizes the instrument deviation is large, and for this reason we only consider particles larger than 30 nm in diameter in this chapter. 

Kulmala M, Vehkamaki H, Petaja T, Dal Maso M, Lauri A, Kerminen V-M, Birmili W, McMurry PH (2004) Formation and growth rates of ultrafine atmospheric particles a review of observations. J Aerosol Sci 35 143-176... 

Dockery DW, Pope CA, Xu XP, Spengler JD, Ware JH, Fay ME, Ferris BG, Speizer FE (1993) An association between air pollution and mortality in 6 United States cities. N Engl J Med 329 1753-1759 Donaldson K, Li XY, MacNee W (1998) Ultrafine (nanometre) particle mediated lung injury. J Aerosol Sci 29 553-560... 

Jefferson DA (2000) The surface activity of ultrafine particles. Phil Trans Roy Soc Lond A 358 2683-2692 Jose-Yacamai M (1998) The role of nanosized particles. A frontier in modem materials science, from nanoelectronics to environmental problems. Metall Mater Trans A 29 713-725 Kalberer M, Ammann M, Arens F, Gaggeler HW, Baltensperger U (1999) Heterogeneous formation of nitrous acid (HONO) on soot aerosol particles. J Geophys Res 104 13825-13832 Kamm S, Mohler O, Naumann KH, Saathoff H, Schurath U (1999) The heterogeneous reaction of ozone with soot aerosol. Atmos Environ 33 4651-4661... 

Kane DB, Johnston MV (2000) Size and composition biases on the detection of individual ultrafine particles by aerosol mass spectrometry. Environ Sci Technol 34 4887-4893 Ka rcher B, Turco RP, Yu F, Danilin MY, Weisensdn DK, Miake-Lye RC, Busen R (2000) A unified model for ultrafine aircraft particle emissions. J Geophys Res 105 29379-29386 Kashchiev D (1982) On the relation between nucleation work, nucleus size, and nucleation rate. J Chem Phys 76 5098-5102... 

Stark JV, Park DG, Lagadic I, Klabunde KJ (1996) Nanoscale metal oxide particles/clusters as chenucal reagents-tJnique surface chemistry on magnesium oxide as shown by enhanced adsorption of acid gases (sulfur dioxide and carbon dioxide) and pressure dependence. Chem Mater 8 1904-1912 Stolzenburg MR, McMurry PH (1991) An ultrafine aerosol condensation nucleus counter. Aerosol Sci Tech 14 48-65... 

Ultrafine aerosols are commonly defined as particles with diameters less than 0.1 /rm fine particles have diameters of approximately 0.1 to 2 /xm. Fine particles may be formed by coagulation of ultrafine particles or through gas to particle conversion processes. In industrialized areas, fine particles tend to be mainly composed of SO -, NO3, NFff (all from gas to particle conversion processes), elemental carbon, organic carbon, and trace metals. Particles formed from gases are typically less than 1 ptm in diameter and cause reduced... 

The deposition in the mouth is largely due to impaction (except for ultrafine aerosols). This mode of deposition therefore increases with particle size and velocity. The reduction of oropharyngeal deposition is desirable both to improve the efficiency of lung deposition and to reduce its variability [26]. To accomplish this, the velocity of the particles must be sufficiently low. The lower bound for the particle velocity is dictated by the inspiratory flow carrying the aerosol cloud. But some aerosol generators impart high velocity to the particles in the course of formation of the aerosol cloud. 

Particle transport and deposition from lurbuieni flows by inertial forces are not well understood and has been the subject of considerable experimental and theoretical study, Correlaiions for rates of particle deposition from lurbuieni pipe flow are discussed in this chapter. The concentrations are a.s.sumed to be sufficiently small to neglect the effects of the particles on the turbulence. Inertial effects can also be used to focus beams of aerosol particles. This effect can be pniduced for suhmicron and even ultrafine particles as described at the end olThe chapter. 

---