Wetting experiments

Several semi-empirical calculations are based on wetting. They are discussed together with wetting experiments in Section III.8. 

Kang et al. first studied the wetting properties of 4 -methyl- (MMB) and 4 -hy-droxy-4-mecaptobiphenyls (HMB) as an analog system for the ahphatic HUT/DDT mixed monolayer [97]. In Fig. 9.10 the results of analog wetting experiments for the two systems are compared. 

Surface reconstruction of the PS-PMMA brush in selective solvents gave rise to pattern formation which was investigated by SPM, wetting experiments and XPS. The obtained morphologies depended on the thickness of the brush and its composition [283, 284] (Fig. 9.31). 

In a series of papers, Matsuda et al. [291-295] employed RAFT-SIP with immobilized benzyl N,N-diethyldithiocarbamate to form polymer brushes from styrene, methacrylamides, acrylamides and acrylates, NIPAM and N-vinyl-2-pyrrolidone on various surfaces. The SIP is initiated by UV irradiation of the surface-bonded dithiocarbamates. Thermoresponsive polymer brushes were prepared by the polymerization of NIPAM and investigated by XPS, wetting experiments and mainly SPM [294]. Patterned polymer brush layers were also prepared. When chloro-methyl styrene was used as a comonomer, RAFT-SIP resulted in branching. By control of the branching, spatio-resolved hyperbranching of a controllable stem/ branch design was realized (Fig. 9.32) [293, 295]. 

The wetting experiments to be described were performed on Pb single-crystals. Interpretation of the results requires a knowledge of the surface energy anisotropy of solid Pb, as well as the atomic scale physical state of Pb surfaces of different orientations. These features of Pb surfaces have been studied by several authors in great detail and are described in the following seetion. 

The available area for a liquid phase oxidation, then, should have little relation to the surface area determined by a gas absorptions and heat of wetting experiments. 

It is apparent from Fig. 1 that the water evolution profile is qualitatively similar for water-sized and silane-treated glass fibers. Table 4 shows, however, that the desorption volume of physically adsorbed water (peak 1) is significantly larger for water-sized glass than for silane-treated specimens. This result is in qualitative accord with evidence from wetting experiments demonstrating that silane deposition diminishes the non-dispersive component of the work of adhesion with water [2-5], When bare and silane-treated fibers were equilibrated with water for 6 months, as opposed to several hours in this study, the desorption volumes of... 

Ghetta, V., Fouletier, J. and Chatain, D., Oxygen adsorption isotherms at the surfaces of liquid Cu and Au-Cu alloys and their interfaces with A1203 detected by wetting experiments , Acta. Mater., 1996 44(5) 1927-1936. 

In this work, ordered arrays of core-shell particles were used as model surfaces to study the water wetting behaviour of these surfaces. Two factors were varied in the wetting experiments (i) the shell chemistry and hence the solid surface tension of the organic shell, and (ii) the height roughness from sub- xm up to xm roughness values whereas the Wenzel roughness factor was kept constant. 

Wetting experiments with liquid tin on heterogeneous surfaces composed of oxide glass ceramic (a) and molybdenum (/ ) with 0 = 125° and 0 = 18° were performed using the sessile drop technique (Voitovich 1992, Naidich et al. 1995). 

Figure 2.12. Effect of velocity parameter Ui /

The computational predictions based on the transition state simulations were followed by wet experiments [117]. The wet experiments have revealed that A199S/S287G/A328W/Y332G BChE has a 456-fold im-... 

Finally, the similar computational strategy discussed in this chapter in combination with appropriate wet experiments may also be useful in rational redesign of many other metabolic enzymes for the therapeutic treatments of metabolic diseases. 

From wetting experiments on apolar surfaces = y ) the Lifshitz-van der Waals portions of... 

The properties of the liquid precursors (Table 2) were investigated by wetting experiments on a perfluoroalkyl methacrylate (FC 722 , 3M) covered glass plate (solid surface tension y 12.5 mN/m)[ll]. 

We are very undebted to Professor Widom for his suggestion concerning the wetting experiments. 

Fig. 2 displays the results for CeH-ZSM-5. Though the catalyst only contains 0.64 wt% Ce, the activity reached peak conversions higher than 80%. At high temperatures there is a small NOx conversion decrease. The presence of water shifted the maximum conversion to higher temperatures in both the ascending and descending temperature curve. No fiirther deactivation was noticed, as a second wet experiment (not shown here) gives the same activities as the first wet experiment which is shown in Fig. 2. 

Figure I. The suction curve (dashed) and the Febex fit (solid). The wetting experiment of a confined sample with p, = I600...I650kg/m ...

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