Linked Life Data

15927598

Source:http://linkedlifedata.com/resource/pubmed/id/15927598

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-6-1
pubmed:abstractText
We present the adsorption kinetics and the surface phase behavior of water-soluble n-tetradecyl phosphate (n-TDP) at the air-water interface by film balance and Brewster angle microscopy (BAM). The relaxation of the surface pressure at about zero value in the surface pressure (pi)-time (t) adsorption isotherm is found to occur from 2 to 20 degrees C with appropriate concentrations of the amphiphile. These plateaus are accompanied by two surface phases, confirming that the relaxation of the surface pressure is caused by a first-order phase transition. Only this phase transition is observed at <6.5 degrees C and it is considered as a gas (G)-liquid condensed (LC) phase transition. Above 6.5 degrees C, the phase transition at zero surface pressure is followed by another phase transition, which is indicated by the presence of cusp points in the pi-t curves at different temperatures. Each of the cusp points is followed by a plateau, which is accompanied by two surface phases, indicating that the latter transitions are also first-order in nature. At >6.5 degrees C, the former transition is classified as a first-order G-liquid expanded (LE) phase transition, while the latter transition is grouped into a first-order LE-LC phase transition. The critical surface pressure (pi(c)) necessary for the G-LC and G-LE phase transitions is zero and remains constant all over the studied temperatures, whereas that for the LE-LC transition increases linearly with increasing temperature. Based on these results, we construct a rather elaborated phase diagram that shows that the triple point for Gibbs monolayers of n-TDP is 6.5 degrees C. All the results are consistent with the present understanding of the Langmuir monolayers of insoluble amphiphiles at the air-water interface.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9797
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
288
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
342-9
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Phases and phase transitions in Gibbs monolayers of an alkyl phosphate surfactant.
pubmed:affiliation
Venture Business Laboratory, Utsunomiya University, Yoto 7-1-2, Utsunomiya 321-8585, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't