The influence of particle composition upon the evolution of urban ultrafine diesel particles on the neighbourhood scale
-
Published:2018-12-05
Issue:23
Volume:18
Page:17143-17155
-
ISSN:1680-7324
-
Container-title:Atmospheric Chemistry and Physics
-
language:en
-
Short-container-title:Atmos. Chem. Phys.
Author:
Nikolova Irina, Cai XiaomingORCID, Alam Mohammed Salim, Zeraati-Rezaei Soheil, Zhong Jian, MacKenzie A. RobORCID, Harrison Roy M.ORCID
Abstract
Abstract. A recent study demonstrated that diesel particles in urban air
undergo evaporative shrinkage when advected to a cleaner atmosphere (Harrison
et al., 2016). We explore, in a structured and systematic way, the
sensitivity of nucleation-mode diesel particles (diameter < 30 nm) to
changes in particle composition, saturation vapour pressure, and the mass
accommodation coefficient. We use a multicomponent aerosol microphysics
model based on surrogate molecule (C16−C32 n-alkane)
volatilities. For standard atmospheric conditions (298 K, 1013.25 hPa), and
over timescales (ca. 100 s) relevant for dispersion on the neighbourhood
scale (up to 1 km), the choice of a particular vapour pressure dataset
changes the range of compounds that are appreciably volatile by two to six carbon
numbers. The nucleation-mode peak diameter, after 100 s of model runtime, is
sensitive to the vapour pressure parameterisations for particles with
compositions centred on surrogate molecules between C22H46 and
C24H50. The vapour pressure range, derived from published data,
is between 9.23 × 10−3 and 8.94 × 10−6 Pa for
C22H46 and between 2.26 × 10−3 and
2.46 × 10−7 Pa for C24H50. Therefore, the vapour pressures of
components in this range are critical for the modelling of
nucleation-mode aerosol dynamics on the neighbourhood scale and need to be
better constrained. Laboratory studies have shown this carbon number fraction
to derive predominantly from engine lubricating oil. The accuracy of vapour
pressure data for other (more and less volatile) components from laboratory
experiments is less critical. The influence of a core of non-volatile
material is also considered; non-volatile core fractions of more than 5 %
are inconsistent with the field measurements that we test the model against. We
consider mass accommodation coefficient values less than unity and find
that model runs with more volatile vapour pressure parameterisations and
lower accommodation coefficients are similar to runs with less volatile
vapour pressure parameterisations and higher accommodation coefficients. The
new findings of this study may also be used to identify semi-volatile
organic compound (SVOC) compositions that play dominating roles in the
evaporative shrinkage of the nucleation mode observed in field measurements
(Dall'Osto et al., 2011).
Funder
European Research Council
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference39 articles.
1. Alam, M. S, Rezaei, S. Z., Stark, C. P., Liang, Z., Xu, H. M., and Harrison,
R. M.: The characterisation of diesel exhaust particles – composition, size
distribution and partitioning, Faraday Discuss., 189, 69–84, 2016. 2. Alam, M. S., Zeraati-Rezaei, S., Liang, Z., Stark, C., Xu, H., MacKenzie, A. R., and Harrison, R. M.:
Mapping and quantifying isomer sets of hydrocarbons (≥ C12) in diesel exhaust,
lubricating oil and diesel fuel samples using GC × GC-ToF-MS, Atmos. Meas. Tech., 11, 3047–3058,
https://doi.org/10.5194/amt-11-3047-2018, 2018. 3. Allen, L. R., Donahue, N. M., Shrivastava, M. K., Weitkamp, E. A., Sage, A.
M., Grieshop, A. P., Lane, T. E., Pierce, J. R., and Pandis, S. N.:
Rethinking organic aerosols: semivolatile emissions and photochemical aging,
Science, 315, 1259–1262, 2007. 4. Atkinson, R. W., Fuller, G. W., Anderson, H. R., Harrison, R. M., and
Armstrong, B.: Urban ambient particle metrics and health: a time-series
analysis, Epidemiology, 21, 501–511, 2010. 5. Biswas, S., Ntziachristos, L., Moore, K. F., and Sioutas, C.: Particle
volatility in the vicinity of a freeway with heavy-duty diesel traffic,
Atmos. Environ., 41, 3479–3493, 2007.
Cited by
5 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献
|
|