Role of surface tension

The role of surface tension of liquids is found in many important systems. The capillary vise is found to play an important role in many everyday processes (such as washing and cleaning, plants, etc.). 

Some crystals have a frustrating property as grown they are quite stable and mechanically strong, but when shaped into a sphere they have a strong tendency to cleave almost spontaneously and to fall apart into thin sheets. Gypsum, malonic acid, and oxalic acid dihydrate examplify this type of behavior, which highlights the role of surface tension in the stability of crystals. 

Finholt P and Solvang S. Dissolution Kinetics of Drugs in Human Gastric Juice-Role of Surface Tension. J Pharm Sc 1968 57 1322-1331. 

The dependencies R z) and Z(R), obtained by numerical integration of equations (22.30), are shown in Figs. 22.2 and 22.3 for the various values of parameters q and K. At the initial stage, the surface tension, characterized by the parameter q, exerts a noticeable influence on the bubble growth. At first, bubble growth is impeded by surface tension, and the external boundary of the boundary layer is moving away from the bubble surface. Then, as R grows, the role of surface tension decreases, the thickness of the boundary layer is stabilized and remains constant in time. At the same time, Z (1 + ) and, as we see from the last equation (22.30), the relative density of gas in the bubble decreases and also remains constant. 

Lest the reader think that 2-D foams are just figments of the imagination, it must be pointed out that they can be generated - or at least closely approximated - by squeezing a 3-D foam between two narrowly spaced, wetted, transparent plates (2, 31-35). Structurally even closer realizations may be obtained in phase-coexistence regions of insoluble monolayers of surface-active molecules at the air-water interface (36), where the role of surface tension is taken over by the line tension at the phase boundaries.]... 

It has been suggested that the role of surface tension forces in the dynamic wetting process may be represented by... 

In Section 1.2 we have discussed the important role of surface tension in multiphase flows through microchannel networks. This behavior is in stark contrast to... 

Similarly to crystals (see Table 7.3), the free surfaces of liquid metals and alloys have been proven experimentally to be layered. Thus, in liquid Ga the contraction in the surface layer is Ad 2 = 10% [80], inin Acfn = 14% [81], in liquid Sn Acrystal structure) the surface layer is expanded by 10 % because of the van der Waals interaction of the neighboring atoms [83]. Authors of [84] considered the role of surface tension in the surface layering of liquids and noted that according to recent theoretical works, at low enough temperatures the free surfaces of all liquids should become layered, unless preempted by bulk freezing. 

Shpyrko O, Fukuto M, Pershan P et al (2004) Surface layering of liquids the role of surface tension. Phys Rev B 69 245423... 

Although Benard was aware of the role of surface tension and surface tension gradients in his experiments, it took, however, five decades to unambiguously assess, experimentally and theoretically [see, for instance, the papers by Block (1956) and Pearson (1958)], that indeed the surface tension gradients rather than buoyancy was the cause of Benard cells in thin liquid films. Only in 1997 this almost evident physical fact has been rigorously proved, through an asymptotic approach, by Zeytounian (1997) ... 

Velocimetry. - An analytic model for the velocity field within a tubeless siphon (Fano flow) was presented. The model was based on a simple differential equation in which extensional, shear and gravitational pressure gradient forces are balanced. The role of surface tension in determining boundary conditions for the flow is considered. The analysis is applied to NMR velocimetry data (Xia and Callaghan, J. Magn. Reson., 2003, 16, 365) on a... 

Besides providing a method to produce future lightweight materials, the study is interesting because it addresses the role of surface tension in drying shrinkage... 

We will first consider the influence of the wetting properties of the colloidal suspension relative to a given substrate. The role of surface tension on the yield of the assembly process can be easily investigated by adding a well-defined concentration of surfactants in the initial suspension. As an example, it was shown that the assembly of 500 nm PS particles on a PDMS substrate was optimum for a contact angle ranging from 30° and 60°. ... 

Profile extrusion is a well-established practice in the polymer industry. Adaptation of profde extrusion to microfabrication, however, is difficult due to scaling-related process changes. Particularly, the effect of surface tension increases as size reduces and could significantly contribute to cross-sectional shape change in microprofile extrusion. In this study, the role of surface tension in microprofile extrusion was numerically studied and compared with that of die swell. Strategies were proposed to reduce the surface tension influence and produce precision microprofiles. 

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