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<front>
<journal-meta>
<journal-id journal-id-type="publisher">ACPD</journal-id>
<journal-title-group>
<journal-title>Atmospheric Chemistry and Physics Discussions</journal-title>
<abbrev-journal-title abbrev-type="publisher">ACPD</abbrev-journal-title>
</journal-title-group>
<issn pub-type="epub">1680-7375</issn>
<publisher><publisher-name>Copernicus GmbH</publisher-name>
<publisher-loc>Göttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acpd-8-9435-2008</article-id>
<title-group>
<article-title>Technical Note: Quantitative long-term measurements of VOC concentrations  by PTR-MS &amp;ndash; measurement, calibration, and volume mixing ratio calculation methods</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Taipale</surname>
<given-names>R.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ruuskanen</surname>
<given-names>T. M.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Rinne</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kajos</surname>
<given-names>M. K.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Hakola</surname>
<given-names>H.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Pohja</surname>
<given-names>T.</given-names>
</name>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kulmala</surname>
<given-names>M.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>University of Helsinki, Department of Physics, P.O. Box 68,  00014 University of Helsinki, Finland</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Finnish Meteorological Institute, Air Quality Research, P.O. Box  503, 00101 Helsinki, Finland</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>University of Helsinki, Hyytiälä Forestry Field Station,  Hyytiäläntie 124, 35500 Korkeakoski, Finland</addr-line>
</aff>
<pub-date pub-type="epub">
<day>23</day>
<month>05</month>
<year>2008</year>
</pub-date>
<volume>8</volume>
<issue>3</issue>
<fpage>9435</fpage>
<lpage>9475</lpage>
<permissions>
<license xlink:type="simple">
<license-p>This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.</license-p>
</license>
</permissions>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/8/9435/2008/acpd-8-9435-2008.html">This article is available from http://www.atmos-chem-phys-discuss.net/8/9435/2008/acpd-8-9435-2008.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/8/9435/2008/acpd-8-9435-2008.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/8/9435/2008/acpd-8-9435-2008.pdf</self-uri>
<abstract>
<p>Proton transfer reaction mass spectrometry (PTR-MS) is a technique for
online measurements of atmospheric concentrations, or volume mixing ratios,
of volatile organic compounds (VOCs). The aim of this paper is to give a
detailed description of our measurement, calibration, and volume mixing
ratio calculation methods, which have been designed for long-term
stand-alone field measurements by PTR-MS. We also show how the information
obtained from a calibration can be used to determine the instrument
specific relative transmission curve, which enables quantitative mixing
ratio calculation for VOCs which are not present in a calibration gas
standard. To illustrate the functionality of our measurement, calibration,
and calculation methods, we present a one-month period of ambient mixing
ratio data measured in a boreal forest ecosystem at the SMEAR II station in
southern Finland. During the measurement period 27 March&amp;ndash;26 April 2007,
the hourly averages of mixing ratios were 0.1&amp;ndash;0.5 ppbv for formaldehyde,
0.2&amp;ndash;3.0 ppbv for methanol, 0.04&amp;ndash;0.39 ppbv for benzene, and 0.03&amp;ndash;1.25 ppbv for monoterpenes.</p>
</abstract>
<counts><page-count count="41"/></counts>
</article-meta>
</front>
<body/>
<back>
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