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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>GÃ¶ttingen, Germany</publisher-loc>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="doi">10.5194/acpd-8-14957-2008</article-id>
<title-group>
<article-title>Mass concentrations of black carbon measured by four instruments in the middle of Central East China in June 2006</article-title>
</title-group>
<contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Kanaya</surname>
<given-names>Y.</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>Komazaki</surname>
<given-names>Y.</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>Pochanart</surname>
<given-names>P.</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>Liu</surname>
<given-names>Y.</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>Akimoto</surname>
<given-names>H.</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>Gao</surname>
<given-names>J.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
</contrib>
<contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Wang</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>Wang</surname>
<given-names>Z.</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
</contrib>
</contrib-group><aff id="aff1">
<label>1</label>
<addr-line>Frontier Research Center for Global Change, Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan</addr-line>
</aff>
<aff id="aff2">
<label>2</label>
<addr-line>Environment Research Institute, Shandong University, Jinan, China</addr-line>
</aff>
<aff id="aff3">
<label>3</label>
<addr-line>Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong, China</addr-line>
</aff>
<aff id="aff4">
<label>4</label>
<addr-line>LAPC/NZC, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China</addr-line>
</aff>
<pub-date pub-type="epub">
<day>05</day>
<month>08</month>
<year>2008</year>
</pub-date>
<volume>8</volume>
<issue>4</issue>
<fpage>14957</fpage>
<lpage>14990</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/8/14957/2008/acpd-8-14957-2008.html">This article is available from http://www.atmos-chem-phys-discuss.net/8/14957/2008/acpd-8-14957-2008.html</self-uri>
<self-uri xlink:href="http://www.atmos-chem-phys-discuss.net/8/14957/2008/acpd-8-14957-2008.pdf">The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/8/14957/2008/acpd-8-14957-2008.pdf</self-uri>
<abstract>
<p>Mass concentrations of black carbon (BC) were determined in June 2006 at the
top of Mount Tai (36.26&amp;deg; N, 117.11&amp;deg; E, 1534 m a.s.l.), located in the
middle of Central East China, using four different instruments: a
multi-angle absorption photometer (5012 MAAP, Thermo), a particle soot
absorption photometer (PSAP, Radiance Research), an ECOC semi-continuous
analyzer (Sunset Laboratory) and an Aethalometer (AE-21, Magee Scientific).
High correlation coefficients (&lt;i&gt;R&lt;/i&gt;&lt;sup&gt;2&lt;/sup&gt;&amp;gt;0.88) were obtained between the
measurements of the BC mass concentrations by the different instruments.
From the range of the slopes of the linear least-square fittings, we
concluded that the BC concentrations regionally-representative of the area
were measured in a range with a maximum-to-minimum ratio of 1.5 (an
exception was that the BC (PM&lt;sub&gt;2.5&lt;/sub&gt;) concentrations derived from MAAP were
~2 times higher than the optical measurements (PM&lt;sub&gt;2.5&lt;/sub&gt;) derived
from the ECOC analyzer). This range is significant, but is still
sufficiently narrow to better constrain the large and highly uncertain
emission rate of BC from China. In detail, two optical instruments (the MAAP
instrument and the PSAP instrument equipped with a heated inlet (400&amp;deg;C)) tended to give higher concentrations than the thermal EC concentrations
observed by the ECOC analyzer. The ratios of optical BC to thermal EC showed
a positive correlation with the OC/EC ratio reported by the ECOC analyzer,
suggesting two possibilities. One is that the optical instruments
overestimated BC concentrations in spite of careful cancellation of the
scattering effect in the MAAP instrument and the expected evaporation of
volatile species by heating the inlet of the PSAP instrument. The other is
that the determined split points between OC and EC were too late when a
large amount of OC underwent charring during the analysis, resulting in an
underestimation of EC by the ECOC analyzer. High ratios of optical BC to
thermal EC were recorded when the NO&lt;sub&gt;x&lt;/sub&gt;/NO&lt;sub&gt;y&lt;/sub&gt; ratio was low, implying
the coating of the particles became thicker in the aged air mass and
resulted in the optical instruments overestimating BC concentrations owing
to the lensing effect.</p>
</abstract>
<counts><page-count count="34"/></counts>
</article-meta>
</front>
<body/>
<back>
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