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<article language="en">
	<journal>
		<journal_title>Atmospheric Measurement Techniques</journal_title>
		<journal_url>www.atmos-meas-tech.net</journal_url>
		<issn>1867-1381</issn>
		<eissn>1867-8548</eissn>
		<volume_number>3</volume_number>
		<issue_number>4</issue_number>
		<publication_year>2010</publication_year>
	</journal>
	<doi>10.5194/amt-3-1063-2010</doi>
	<article_url>http://www.atmos-meas-tech.net/3/1063/2010/</article_url>
	<abstract_html>http://www.atmos-meas-tech.net/3/1063/2010/amt-3-1063-2010.html</abstract_html>
	<fulltext_pdf>http://www.atmos-meas-tech.net/3/1063/2010/amt-3-1063-2010.pdf</fulltext_pdf>
	<start_page>1063</start_page>
	<end_page>1074</end_page>
	<publication_date>2010-08-18</publication_date>
	<article_title content_type="html">High time-resolution chemical characterization of the water-soluble fraction of ambient aerosols with PILS-TOC-IC and AMS</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>H. Timonen</name>
			<email>hilkka.timonen@fmi.fi</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>M. Aurela</name>
		</author>
		<author numeration="3" affiliations="1">
			<name>S. Carbone</name>
		</author>
		<author numeration="4" affiliations="1">
			<name>K. Saarnio</name>
		</author>
		<author numeration="5" affiliations="1">
			<name>S. Saarikoski</name>
		</author>
		<author numeration="6" affiliations="1">
			<name>T. MÃ¤kelÃ¤</name>
		</author>
		<author numeration="7" affiliations="2">
			<name>M. Kulmala</name>
		</author>
		<author numeration="8" affiliations="1,2">
			<name>V.-M. Kerminen</name>
		</author>
		<author numeration="9" affiliations="1,2,3">
			<name>D. R. Worsnop</name>
		</author>
		<author numeration="10" affiliations="1">
			<name>R. Hillamo</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Air Quality Research, Finnish Meteorological Institute, P.O. Box 503, 00101 Helsinki, Finland</affiliation>
		<affiliation numeration="2" content_type="html">Department of Physics, University of Helsinki, P.O. Box 64, 00014 University of Helsinki, Finland</affiliation>
		<affiliation numeration="3" content_type="html">Aerodyne Research, Inc., 45 Manning Road, Billerica, MA 01821-3976, USA</affiliation>
	</affiliations>
	<abstract content_type="html">A particle-into-liquid sampler (PILS) was coupled with a total organic
carbon analyzer (TOC) and two ion chromatographs (IC) to enable high
time-resolution measurements of water-soluble ions and water-soluble organic
carbon (WSOC) by a single sampling and analytical set-up. The new high
time-resolution measurement system, the PILS-TOC-IC, was able to provide
essential chemical and physical information about fast changes in
composition, concentrations and likely sources of the water-soluble fraction
of atmospheric aerosol. The concentrations of major water-soluble ions and
WSOC were measured by the PILS-TOC-IC system from 25 April to 28 May 2009.

&lt;br&gt;&lt;br&gt;

The data of the PILS-TOC-IC setup was compared with the data from the
High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) data
measured from 25 April to 8 May 2009. The measured water-soluble
particulate organic matter (WSPOM) concentration varied typically from 0.10
to 8.8 Î¼g m&lt;sup&gt;âˆ’3&lt;/sup&gt; (on average 1.5 Î¼g m&lt;sup&gt;âˆ’3&lt;/sup&gt;). The WSPOM
contributed on average 51% to particulate organic matter (POM) measured
with the AMS. The correlation between the data of all the online measurement
devices (AMS, PILS-TOC-IC, semicontinuous EC/OC carbon analyzer and TEOM)
was excellent. For sulfate, nitrate and ammonium the correlations between
the PILS-TOC-IC and AMS were 0.93, 0.96 and 0.96, respectively. The
correlation between WSPOM and POM was also strong (&lt;I&gt;r&lt;/I&gt; = 0.88). The identified
sources of WSPOM were long-range transported biomass burning and secondary
organic aerosol (SOA) formation. WSPOM and oxalate produced in biomass
burning were clearly correlated with carbon monoxide.</abstract>
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