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| Titel |
Online measurements of the emissions of intermediate-volatility and semi-volatile organic compounds from aircraft |
| VerfasserIn |
E. S. Cross, J. F. Hunter, A. J. Carrasquillo, J. P. Franklin, S. C. Herndon, J. T. Jayne, D. R. Worsnop, R. C. Miake-Lye, J. H. Kroll |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 15 ; Nr. 13, no. 15 (2013-08-14), S.7845-7858 |
| Datensatznummer |
250085627
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| Publikation (Nr.) |
 copernicus.org/acp-13-7845-2013.pdf |
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| Zusammenfassung |
| A detailed understanding of the climate and air quality impacts of aviation
requires measurements of the emissions of intermediate-volatility and
semi-volatile organic compounds (I/SVOCs) from aircraft. Currently both the
amount and chemical composition of aircraft I/SVOC emissions remain poorly
characterized. Here we characterize I/SVOC emissions from aircraft, using a
novel instrument for the online, quantitative measurement of the mass
loading and composition of low-volatility organic vapors. Emissions from the
NASA DC8 aircraft were sampled on the ground 143 m downwind of the engines
and characterized as a function of engine power from idle (4% maximum rated thrust) through 85% power. Results show that I/SVOC
emissions are highest during engine idle operating conditions, with
decreasing but non-zero I/SVOC emissions at higher engine powers. Comparison
of I/SVOC emissions with total hydrocarbon (THC) measurements, VOC
measurements, and an established emissions profile indicates that I/SVOCs
comprise 10–20% of the total organic gas-phase emissions at idle, and an
increasing fraction of the total gas-phase organic emissions at higher
powers. Positive matrix factorization of online mass spectra is used to
identify three distinct types of I/SVOC emissions: aliphatic, aromatic and
oxygenated. The volatility and chemical composition of the emissions suggest
that unburned fuel is the dominant source of I/SVOCs at idle, while
pyrolysis products make up an increasing fraction of the I/SVOCs at higher
powers. Oxygenated I/SVOC emissions were detected at lower engine powers
(≤30%) and may be linked to cracked, partially oxidized or unburned
fuel components. |
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