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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-11-13693-2011</article-id>
<title-group>
<article-title>Fragmentation vs. functionalization: chemical aging and organic aerosol formation</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Chacon-Madrid</surname>
<given-names>H. 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>Donahue</surname>
<given-names>N. 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>Center for Atmospheric Particle Studies, Carnegie Mellon Univ., Pittsburgh, PA 15213, USA</addr-line>
</aff>
<pub-date pub-type="epub">
<day>05</day>
<month>05</month>
<year>2011</year>
</pub-date>
<volume>11</volume>
<issue>5</issue>
<fpage>13693</fpage>
<lpage>13721</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>
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<abstract>
<p>The transformation process that a carbon backbone undergoes in the
      atmosphere is complex and dynamic.  Understanding all these changes
      for all the species in detail is impossible; however, choosing
      different molecules that resemble progressively higher stages of
      oxidation or aging and studying them can give us an insight into
      general characteristics and mechanisms. Here we determine secondary
      organic aerosol (SOA) mass yields of two sequences of molecules
      reacting with the OH radical at high NO&lt;sub&gt;x&lt;/sub&gt;. Each sequence
      consists of species with similar vapor pressures but a succession of
      oxidation states. The first sequence consists of
      &lt;i&gt;n&lt;/i&gt;-pentadecane, &lt;i&gt;n&lt;/i&gt;-tridecanal, 2-, 7-tridecanone, and
      pinonaldehyde. The second sequence consists of &lt;i&gt;n&lt;/i&gt;-nonadecane,
      &lt;i&gt;n&lt;/i&gt;-heptadecanal and &lt;i&gt;cis&lt;/i&gt;-pinonic acid. Oxidized
      molecules tend to have lower relative SOA mass yields; however,
      oxidation state alone was not enough to predict how efficiently
      a molecule forms SOA. Certain functionalities are able to fragment
      more easily than others, and even the position of these
      functionalities on a molecule can have an effect. &lt;i&gt;n&lt;/i&gt;-Alkanes
      tend to have the highest yields, and &lt;i&gt;n&lt;/i&gt;-aldehydes the lowest.
      &lt;i&gt;n&lt;/i&gt;-Ketones have slightly higher yields when the ketone moiety
      is located on the side of the molecule and not in the center. In
      general, oxidation products remain efficient SOA sources, though
      fragmentation makes them less effective than comparable alkanes.</p>
</abstract>
<counts><page-count count="29"/></counts>
</article-meta>
</front>
<body/>
<back>
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