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<article language="en">
	<journal>
		<journal_title>Atmospheric Chemistry and Physics</journal_title>
		<journal_url>www.atmos-chem-phys.net</journal_url>
		<issn>1680-7316</issn>
		<eissn>1680-7324</eissn>
		<volume_number>7</volume_number>
		<issue_number>15</issue_number>
		<publication_year>2007</publication_year>
	</journal>
	<doi>10.5194/acp-7-4081-2007</doi>
	<article_url>http://www.atmos-chem-phys.net/7/4081/2007/</article_url>
	<abstract_html>http://www.atmos-chem-phys.net/7/4081/2007/acp-7-4081-2007.html</abstract_html>
	<fulltext_pdf>http://www.atmos-chem-phys.net/7/4081/2007/acp-7-4081-2007.pdf</fulltext_pdf>
	<start_page>4081</start_page>
	<end_page>4094</end_page>
	<publication_date>2007-08-03</publication_date>
	<article_title content_type="html">Evaluation and modeling of the size fractionated aerosol particle number concentration measurements nearby a major road in Helsinki &amp;ndash; Part II: Aerosol measurements within the SAPPHIRE project</article_title>
	<authors>
		<author numeration="1" affiliations="1,2">
			<name>T. Hussein</name>
			<email>tareq.hussein@helsinki.fi</email>
		</author>
		<author numeration="2" affiliations="3">
			<name>J. Kukkonen</name>
		</author>
		<author numeration="3" affiliations="3,4">
			<name>H. Korhonen</name>
		</author>
		<author numeration="4" affiliations="3">
			<name>M. Pohjola</name>
		</author>
		<author numeration="5" affiliations="1,5">
			<name>L. Pirjola</name>
		</author>
		<author numeration="6" affiliations="6">
			<name>D. Wraith</name>
		</author>
		<author numeration="7" affiliations="3">
			<name>J. Härkönen</name>
		</author>
		<author numeration="8" affiliations="3">
			<name>K. Teinilä</name>
		</author>
		<author numeration="9" affiliations="1,7">
			<name>I. K. Koponen</name>
		</author>
		<author numeration="10" affiliations="3">
			<name>A. Karppinen</name>
		</author>
		<author numeration="11" affiliations="3">
			<name>R. Hillamo</name>
		</author>
		<author numeration="12" affiliations="1">
			<name>M. Kulmala</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">University of Helsinki, Department of Physical Sciences, Finland</affiliation>
		<affiliation numeration="2" content_type="html">Stockholm University, Department of Applied Environmental Science, Sweden</affiliation>
		<affiliation numeration="3" content_type="html">Finnish Meteorological Institute, Air Quality Research, Finland</affiliation>
		<affiliation numeration="4" content_type="html">Institute for Atmospheric Science, School of Earth and Environment, University of Leeds, UK</affiliation>
		<affiliation numeration="5" content_type="html">Helsinki Polytechnic, Department of Technology, Finland</affiliation>
		<affiliation numeration="6" content_type="html">School of Mathematical Science, Queensland University of Technology, Brisbane, Australia</affiliation>
		<affiliation numeration="7" content_type="html">Department of Chemistry, University of Copenhagen, Denmark</affiliation>
	</affiliations>
	<abstract content_type="html">This study presents an evaluation and modeling exercise of the size
fractionated aerosol particle number concentrations measured nearby a major
road in Helsinki during 23 August&amp;ndash;19 September 2003 and 14 January&amp;ndash;11
February 2004. The available information also included
electronic traffic counts, on-site meteorological measurements, and urban
background particle number size distribution measurement. The ultrafine particle (UFP, diameter&amp;lt;100 nm) number
concentrations at the roadside site were approximately an order of magnitude
higher than those at the urban background site during daytime and downwind
conditions. Both the modal structure analysis of the particle number size
distributions and the statistical correlation between the traffic density
and the UFP number concentrations indicate that the UFP were evidently from
traffic related emissions. The modeling exercise included the evolution
of the particle number size distribution nearby the road during downwind
conditions. The model simulation results revealed that the evaluation of the
emission factors of aerosol particles might not be valid for the same site
during different time.</abstract>
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</article>

