% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Massling:20028,
author = {Massling, A. and Niedermeier, N. and Henning, T. and Fors,
E.O. and Swietlicki, E. and Ehn, M. and Hämeri, K. and
Villani, P. and Laj, P. and Good, N. and McFiggans, G. and
Wiedensohler, A.},
title = {{R}esults and recommendations from an intercomparison of
six {H}ygroscopicity-{TDMA} systems},
journal = {Atmospheric measurement techniques},
volume = {4},
issn = {1867-1381},
address = {Katlenburg-Lindau},
publisher = {Copernicus},
reportid = {PreJuSER-20028},
pages = {485 - 497},
year = {2011},
note = {The H-TDMA calibration and intercomparison workshop held at
the WMO-GAW World Calibration Centre for Aerosol Physics,
Leipzig, Germany, was supported by the EU-projects ACCENT
(GOCE-CT-2004-505337), EUSAAR (RII3-CT-2006-14 026140) and
by the German Federal Environment Agency (FKZ: 351 01 046:
GAW World Calibration Centre).},
abstract = {The performance of six custom-built Hygrocopicity-Tandem
Differential Mobility Analyser (H-TDMA) systems was
investigated in the frame of an international calibration
and intercomparison workshop held in Leipzig, February 2006.
The goal of the workshop was to harmonise H-TDMA
measurements and develop recommendations for atmospheric
measurements and their data evaluation. The H-TDMA systems
were compared in terms of the sizing of dry particles,
relative humidity (RH) uncertainty, and consistency in
determination of number fractions of different hygroscopic
particle groups. The experiments were performed in an
air-conditioned laboratory using ammonium sulphate particles
or an external mixture of ammonium sulphate and soot
particles.The sizing of dry particles of the six H-TDMA
systems was within 0.2 to $4.2\%$ of the selected particle
diameter depending on investigated size and individual
system. Measurements of ammonium sulphate aerosol found
deviations equivalent to $4.5\%$ RH from the set point of
$90\%$ RH compared to results from previous experiments in
the literature. Evaluation of the number fraction of
particles within the clearly separated growth factor modes
of a laboratory generated externally mixed aerosol was done.
The data from the H-TDMAs was analysed with a single fitting
routine to investigate differences caused by the different
data evaluation procedures used for each H-TDMA. The
differences between the H-TDMAs were reduced from
$+12/-13\%$ to $+8/-6\%$ when the same analysis routine was
applied. We conclude that a common data evaluation procedure
to determine number fractions of externally mixed aerosols
will improve the comparability of H-TDMA measurements.It is
recommended to ensure proper calibration of all flow,
temperature and RH sensors in the systems. It is most
important to thermally insulate the aerosol humidification
unit and the second DMA and to monitor these temperatures to
an accuracy of 0.2 degrees C. For the correct determination
of external mixtures, it is necessary to take into account
size-dependent losses due to diffusion in the plumbing
between the DMAs and in the aerosol humidification unit.},
keywords = {J (WoSType)},
cin = {IEK-8},
ddc = {550},
cid = {I:(DE-Juel1)IEK-8-20101013},
pnm = {Atmosphäre und Klima},
pid = {G:(DE-Juel1)FUEK491},
shelfmark = {Meteorology $\&$ Atmospheric Sciences},
typ = {PUB:(DE-HGF)16},
UT = {WOS:000288911000007},
doi = {10.5194/amt-4-485-2011},
url = {https://juser.fz-juelich.de/record/20028},
}