Apparent Anomalies in Surface Excesses Determined from Neutron Reflection and the Gibbs Equation in Anionic Surfactants with Particular Reference to Perfluorooctanoates at the Air/Water Interface

Langmuir ◽  
1996 ◽  
Vol 12 (10) ◽  
pp. 2446-2453 ◽  
Author(s):  
S. W. An ◽  
J. R. Lu ◽  
R. K. Thomas ◽  
J. Penfold
Keyword(s):  
Anionic Surfactants ◽  
Water Interface ◽  
Gibbs Equation ◽  
Neutron Reflection ◽  
Air Water Interface

scholarly journals Measurements of adsorption at the air-water interface by the microtome method

1936 ◽  
Vol 154 (883) ◽  
pp. 608-623 ◽  
Keyword(s):  
Dynamic Method ◽  
Fundamental Importance ◽  
Molecular Adsorption ◽  
Water Interface ◽  
Experimental Demonstration ◽  
Gibbs Equation ◽  
Experimental Conditions ◽  
Moving Surface ◽  
Wide Range ◽  
Air Water Interface

In spite of the wide use and fundamental importance of the classical Gibbs adsorption theorem, its validity has never been given adequate experimental demonstration. Until quite recently the principal means available for testing this theorem was the “moving bubble method”, developed by Donnan and Barker, and later by McBain, Davies, and DuBois. Almost without exception this method has given results many times greater than the values calculated from either the exact or the approximate Gibbs equation. A recent exhaustive investigation of this dynamic method by DuBois and Todd has shown, moreover, that the results for moving bubbles may be varied and controlled over a wide range by merely altering the size or speed of the bubbles or the amount of accompanying liquid. Thus the results, although definite and repro­ducible, vary greatly with the experimental conditions, and hence they bear no definite relation either to the Gibbs value or to that for mono-molecular adsorption. It is evident that a moving surface carries in general an amount of adsorbed material which is much greater than that predicted by the Gibbs theorem. Similar high results are reported by Seymour, Tartar, and Wright for moving droplets of benzene in water, which may carry with them as much soap as would correspond to twenty or more mono-layers.

Structure of Monolayers of Monododecyl Dodecaethylene Glycol at the Air−Water Interface Studied by Neutron Reflection

1997 ◽  
Vol 101 (49) ◽  
pp. 10332-10339 ◽  
Author(s):  
J. R. Lu ◽  
T. J. Su ◽  
Z. X. Li ◽  
R. K. Thomas ◽  
E. J. Staples ◽  
...  
Keyword(s):  
Water Interface ◽  
Neutron Reflection ◽  
Air Water Interface ◽  
Dodecaethylene Glycol

Modeling Adsorption of Cationic Surfactants at Air/Water Interface without Using the Gibbs Equation

Langmuir ◽  
2013 ◽  
Vol 29 (15) ◽  
pp. 4743-4749 ◽  
Author(s):  
Chi M. Phan ◽  
Thu N. Le ◽  
Cuong V. Nguyen ◽  
Shin-ichi Yusa
Keyword(s):  
Cationic Surfactants ◽  
Water Interface ◽  
Gibbs Equation ◽  
Air Water Interface

Structural conformation of lysozyme layers at the air/water interface studied by neutron reflection

1998 ◽  
Vol 94 (21) ◽  
pp. 3279-3287 ◽  
Author(s):  
J. R. Lu ◽  
T. J. Su ◽  
R. K. Thomas ◽  
J. Penfold ◽  
J. Webster
Keyword(s):  
Water Interface ◽  
Neutron Reflection ◽  
Structural Conformation ◽  
Air Water Interface
Sign in / Sign up

Export Citation Format

Share Document