Source:http://linkedlifedata.com/resource/pubmed/id/20218612
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
14
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pubmed:dateCreated |
2010-4-8
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pubmed:abstractText |
The reactivity of photolytically generated, gas-phase, ground-state atomic oxygen, O((3)P), with the surfaces of a series of 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([NTf(2)]) ionic liquids has been investigated. The liquids differ only in the length of the linear C(n)H(2n+1) alkyl side chain on the cation, with n = 2, 4, 5, 8, and 12. Laser-induced fluorescence was used to detect gas-phase OH v' = 0 radicals formed at the gas-liquid interface. The reactivity of the ionic liquids increases nonlinearly with n, in a way that cannot simply be explained by stoichiometry. We infer that the alkyl chains must be preferentially exposed at the interface to a degree that is dependent on chain length. A relatively sharp onset of surface segregation is apparent in the region of n = 4. The surface specificity of the method is confirmed through the nonthermal characteristics of both the translational and rotational distributions of the OH v' = 0. These reveal that the dynamics are dominated by a direct, impulsive scattering mechanism at the outer layers of the liquid. The OH v' = 0 yield is effectively independent of the bulk temperature of the longest-chain ionic liquid in the range 298-343 K, also consistent with a predominantly direct mechanism. These product attributes are broadly similar to those of the benchmark pure hydrocarbon liquid, squalane, but a more detailed analysis suggests that the interface may be microscopically smoother for the ionic liquids.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:status |
PubMed-not-MEDLINE
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pubmed:month |
Apr
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pubmed:issn |
1520-5215
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pubmed:author | |
pubmed:issnType |
Electronic
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pubmed:day |
15
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pubmed:volume |
114
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
4896-904
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pubmed:year |
2010
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pubmed:articleTitle |
O(3P) atoms as a chemical probe of surface ordering in ionic liquids.
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pubmed:affiliation |
School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK.
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pubmed:publicationType |
Journal Article
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