Source:http://linkedlifedata.com/resource/pubmed/id/17432881
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
10
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| pubmed:dateCreated |
2007-5-1
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| pubmed:abstractText |
The oxidation kinetics of a-CHx overcoats during exposure to oxygen and water vapor have been measured using X-ray photoemission spectroscopy (XPS) in an apparatus that allows oxidation and analysis of freshly deposited a-CHx overcoats without prior exposure of the overcoats to air. The uptake of oxygen on the surfaces of the a-CHx overcoats has been measured at O2 and H2O pressures in the range 10(-7)-10(-3) Torr at room temperature. The uptake of oxygen during O2 exposures on the order of 10(7) Langmuirs leads to saturation of the a-CHx overcoat surfaces at oxidation levels on the order of 20%. This indicates that the surfaces of a-CHx overcoats are relatively inert to oxidation in the sense that the dissociative sticking coefficient of O2 is approximately 10(-6). Oxygen uptake during exposure to H2O vapor is similar to the uptake during exposure to O2 gas. Although the surfaces of the a-CHx overcoats are quite inhomogeneous, it has been possible to model the uptake of oxygen on their surfaces using a fairly simple Langmuir-Hinshelwood mechanism. Interestingly, the saturation coverage of oxygen during exposure to air at atmospheric pressure is approximately 6%, significantly lower than that obtained during low-pressure exposure to O2 gas or H2O vapor.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
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| pubmed:month |
May
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| pubmed:issn |
0743-7463
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| pubmed:author | |
| pubmed:issnType |
Print
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| pubmed:day |
8
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| pubmed:volume |
23
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
5485-90
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| pubmed:year |
2007
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| pubmed:articleTitle |
Oxidation kinetics of hydrogenated amorphous carbon (a-CH(x)) overcoats for magnetic data storage media.
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| pubmed:affiliation |
Department of Chemical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
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| pubmed:publicationType |
Journal Article
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