Source:http://linkedlifedata.com/resource/pubmed/id/20214389
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
6
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| pubmed:dateCreated |
2010-3-10
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| pubmed:abstractText |
Simultaneous measurements of small-angle light scattering/shear stress (Rheo-SALS) and small-angle X-ray scattering/shear stress (Rheo-SAXS) have been performed in the lamellar phase of the C(16)E(7)/D(2)O system. As the temperature is increased and exceeds 67 degrees C at constant shear rates (at 1 and 3 s(-1)), the shear stress increases abruptly and a four-lobe pattern is observed in the depolarized SALS. These results suggest that the lamellar-to-onion transition occurs with increasing temperature, which has not yet been reported. The diameter of onions obtained from the depolarized SALS pattern at 3 s(-1) increases with increasing temperature. The transition is reversible against the change in temperature. The Rheo-SALS measurements have also been made with a stepwise increase in shear rate at constant temperature. The results are consistent with the above temperature-scan experiments at constant shear rate, suggesting that the transition does not depend on the path. The variation of the SAXS pattern at 3 s(-1) indicates that the orientation of lamellae becomes isotropic as the temperature is increased from 67 to 69 degrees C, which also supports the lamellar-to-onion transition. The transition temperature at constant shear rate (at 3 s(-1)) increases rapidly with a slight increase in surfactant concentration. From this, together with the SAXS results at rest in our previous study, we deduce that an increase in the water-layer thickness is necessary for the lamellar-to-onion transition with increasing temperature.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
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| pubmed:month |
Mar
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| pubmed:issn |
1520-5827
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| pubmed:author | |
| pubmed:issnType |
Electronic
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| pubmed:day |
16
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| pubmed:volume |
26
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| pubmed:owner |
NLM
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| pubmed:authorsComplete |
Y
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| pubmed:pagination |
3835-42
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| pubmed:year |
2010
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| pubmed:articleTitle |
Lamellar-to-onion transition with increasing temperature under shear flow in a nonionic surfactant/water system.
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| pubmed:affiliation |
Department of Chemistry, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan.
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| pubmed:publicationType |
Journal Article
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