Contact angle intrinsic

Consider a vertical solid wall of a crucible consisted of two macroscopic phases a and / separated by a plane intersecting the solid wall by an horizontal straight line (Figure 1.29.a). The intrinsic contact angles on the two phases are such that 0 > 6P, and for the sake of simplicity 0 > 90° and 0P < 90°. Moreover, we assume that the level of liquid in the crucible far from the wall is such that h2 <3C z p, where z p is the maximum meniscus height on the p phase i.e., z p would be the meniscus rise on a homogeneous vertical plate of j3 (equation (1.23)). During... 

Liquid metals wet well metallic substrates (0 interfacial interactions unless the metallic surfaces are oxidized. Adsorption of oxygen on solid substrates can increase contact angles by tens of degrees. Intrinsic wetting seems to be slightly improved in systems with some solubility or which form intermetallics. The main effect of interfacial reactions is the disruption of oxide layers covering the metallic surfaces, allowing the formation of real metal-metal interfaces. 

Intrinsic hysteresis is a direct result of surface configuration change, which occurs as a result of wetting the surface with water. The plates were purposely immersed to a deeper immersion depth in the second cycle to observe the extent of intrinsic hysteresis. Significant surface configuration change affects the calculated contact angles on immersion and emersion, which violates the assumption of... 

Plasma-polymerized materials differ significantly from those polymerized by conventional methods in their surface properties, and surface tension values do not correspond. This difference may be due to the highly cross-linked nature of plasma polymers or to the incorporation of other entities from the carrier gas. These effects are more important than the intrinsic differences in backbone fiexibility. Wrobel (88) presents ATR-IR (attenuated total reflection infrared) spectroscopic data indicating that silazanes and silanes cross-link more readily than do siloxanes under plasma conditions. Wrobel and his co-workers (89) have also used contact angles to study the thermal decomposition of plasma-polymerized organosilicon polymers. 

Our data indicate a clear difference in the organic content of Atlantic and Chesapeake Bay sea waters. The ratio of intrinsic humus fluorescence at 420 nm to the amine-generated fluorescence with fluorescamine is quite different in the two samples. The different contact angles produced by films adsorbed from these two samples are indicative of different materials adsorbed. The data shown in Table II indicate that the ratio of depletion of humus fluorescence to depletion of amine signal is apparently higher in Bay water than in Atlantic waters and, although somewhat equivocal, a difference in reaction of the dissolved organics with surfaces is implied. 

U Kusumaalmaja, H., Ii, Y., Diniova, R., and lipowsky, R. (2009) Intrinsic contact angle of aqueous phases at membranes and vesides. Physical Review Letters, 103 (23), 238103-238104. 

Relationship of Observed Angles to Intrinsic Angle, As stated by Shuttleworth and Bailey [8j, the e erimentally observed contact angle, < ), is the sum of the intrinsic angle, 0, plus the slope angle, o, of the surface at the point of contact ... 

If we consider the ratio Zq/x to be a measure of roughness, it is clear that possible hysteresis decreases as surface roughness decreases, and that the maximum and minimum possible angles are symmetrical about the intrinsic contact angle, 6. Furthermore, the ratio Zq/xq, rather than the absolute value of either z or x, determines the maximum possible hysteresis. 

Intrinsic contact angle 6 Contact angle given by y cos 6 = yS - ySl... 

Uilk JM, Mera AE, Fox RB, Wynne KJ (2003) Hydrosilation-cured poly(dimethylsiloxane) networks intrinsic contact angles via dynamic contact angle analysis. Macromolecules 36 3689-3694... 

In this relation, x denotes the fluid front position as a function of time t, system architectures a and b, and intrinsic material properties including contact angles of the fluid upon the hydrophilic and hydrophobic materials 0i and 2, respectively. The solution to this second-order ordinary differential equatimi with respect to meniscus position squared can be solved relatively easy through numerical techniques. The solution determined by the investigators of this approach is in excellent agreement with experimental results [7]. Furthermore, the investigators demonstrated that confluent monolayers of cells could be cultured in their apparatus and proteins could be selectively adsorbed upon the device surface [7]. Consequently, the surface-directed... 

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