Adsorbed Langmuir

W. D. Machin. Temperature of hysteresis and the pore size distributions of two mesoporous adsorbents. Langmuir 70 1235-1240, 1994. 

The presence of adsorbed Langmuir monolayers may induce very high changes in the surface potential of water. For example, A% shifts attaining ca. -0.9 (hexadecylamine hydrochloride) and ca. + 1.0 V (per-fluorodecanoic acid) have been observed. " ... 

The physical meaning of the g" (ion) potential depends on the accepted model of ionic double layer. The proposed models correspond to the Gouy Chapman diffuse layer, with or without allowance for the Stern modification and/or the penetration of small counterions above the plane of the ionic heads of the adsorbed large ions [17,18]. The presence of adsorbed Langmuir monolayers may induce very high changes of the surface potential of water. For example. A/" shifts attaining ca. —0.9 (hexadecylamine hydrochloride), and ca. -bl.OV (perfluorodecanoic acid) have been observed [68]. 

It is necessary to remind ourselves, that the adsorption of humic acids or fulvic acids correspond to the adsorption of a mixture of adsorbates. Adsorption equations derived for the adsorption of a single adsorbate (Langmuir, Frumkin or Gibbs Equation) cannot be used for mechanistic interpretation of the data even if these data can be fitted to such equations (Tomaic and Zutic, 1988). 

I) Reaction occurs while both species are adsorbed (Langmuir-Hinshel-wood kinetics). 

Ray, K., Badugu, R., and Lakowicz, J. R. (2007). Sulforhodamine Adsorbed Langmuir-Blodgett Layers on Silver Island Films Effect of Probe Distance on the Metal-Enhanced Fluorescence. Journal of Physical Chemistry C 111 7091-7097. 

Sulforhodamine adsorbed Langmuir-Blodgett layers on silver island films effect of probe distance on the metal-enhanced fluorescence. J. Phys. Chem. 

Hulteen, J.C., Young, M.A., and Van Duyne, R.P. (2006) Surface-enhanced hyper-Raman scattering (SEHRS) on Ag film over nanosphere (EON) electrodes surface symmetry of centrosymmetric adsorbates. Langmuir, 22, 10354-10364. 

Salem, M.M.K., Braeuer, P., Szombathely, M.V., et al. (1998). Thermodynamics of high pressure adsorption of argon, nitrogen, and methane on microporous adsorbents. Langmuir, 14, 3376-89. 

In this chapter, we will discuss how the chemical and physical properties of substances at interfaces differ from those in the bulk. For quantitative description, quantities like surface tension and surface energy have to be introduced. With the help of these quantities, phenomena known from everyday life like the lotus effect can be explained. However, perhaps you are more interested to learn how detergents clean Then have a look at Sect. 16.3 which deals with the adsorption on liquid surfaces. The next section covers the adsorption on solid surfaces and the variation of the extent of coverage with pressure or concentration of the substance to be adsorbed. Langmuir s isotherm, the simplest description of such an adsorptiOTi process, is deduced by kinetic interpretation of the adsorption equilibrium. Alternatively, it can be derived by introducing the chemical potential of free and occupied sites and cmisideiing the equilibrium condition. In the last part of the chapter, some important applications such as surface measurement and adsorption chromatography are discussed. 

Adsorbent Langmuir Isotherm Parameters Freundlich Isotherm Parameters Thermodynamic Parameter... 

Lam KF, Yeimg KL, Mckay G (2006) A rational approach in the design of selective mesoporous adsorbents. Langmuir 22 9632-9641... 

Schneider, H.M., Frantz, P., Granick, S. The bimodal energy landscape when polymers adsorb. Langmuir 12(4), 994-996 (1996)... 

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