Tension parameter

This method does not attempt to distinguish between the various energy contributions. The surface tension parameter acts to include all interactions as much as possible. There are a number of algorithms for implementing this method, most of which differ in the means for determining the surface area associated with a particular group. This method is particularly popular for very large molecules, which can only be modeled by molecular mechanics. 

Density in liquid Density in bubble Surface tension Parameter in Eq. (3)... 

Van Oss CJ, Good RJ, Busscher RJ. (1990). Estimation of the polar surface tension parameters of glycerol and formamide, for use in contact angle measurements on polar solids. / Dispers Sci Technol 11 75-81. 

Fig. 8 Monomer chemical potential in a droplet comprising monomer and hydrophobe as a function of the monomer volume fraction (top) and droplet radius (bottom). The global potential (as given by Ugelstad s equation) is given, as well as the entropic term due to mixing and the Laplace term due to surface tension. Parameters m Y=l Vm,h=0 y=25 mN/m Vjn=l-1 10 m mol T=298.15 K (p =0,96 r =100 nm...

In the original work on the four-point scheme, (and much of the later exploration), schemes which are a linear combination of [0,l,2,l,0]/2 and [-1,0,9,16,9,0 -1]/16 were considered, the exact linear combination being defined by a tension parameter. These schemes were all interpolating. 

The value of AC( = Yl cos 0) from case (3) can be introduced into Eq. I9. Now, using three liquids, e.g., n-alkanc. water, and formamide. for which the surface tension parameters and viscosities are known, it is possible to determine Ys. Ys Ys fo tested solid under the proper experimental conditions I —4. 

P Doe, M El-Emary, JC Morgan, RS Schechter, WH Wade. Systematic studies of low interfacial tension parameters. Second ERDA Symposium on Enhanced Oil and Gas Recovery, Tulsa, 1976, Paper B-6, Petroleum Publishing Co. 

Connected with the surface tension parameter is the wetting process of the surface, e.g. fabrics or hard surfaces. This wetting can be described by the Young equation (see Figure 3.5) ... 

How do we calculate these surface tension parameters Van Oss, Good, and their co-workers [49-50,53-57] have developed a three-liquid procedure [Equation (21)] to determine js by using contact angle technique and a... 

TABLE 6.1. Surface Tension Parameters (in mJ/m ) of Testing Liquids. 

Deionized water (prepared in this laboratory), glycerol (from BDH), for-mamide (Unilab), and diiodomethane (from Nacalai Tesque) have been chosen as the testing liquids because there are significant data available for these liquids. Table 6.1 tabulates their basic surface tension parameters (in mJ/m ) [45,59]. 

The surface tensions are the products of the tension parameters of adjoining phases, which depend only on the bulk properties ... 

The tension parameter of a binary liquid mixture with composition xi can be calculated from the fundamental isotherm according to... 

More recently. Topping developed a methodology for an analytical solution to calculate the movement of organic material from the bulk to a surface layer, requiring only surface tension parameters from binary systems [265]. He found that the method was computationally efficient, but it must be validated by comparisons with laboratory experimental data, and then further with ambient studies and smog chambers. 

Another experimental example of the use of the drop and bubble shape technique is given in Figure 12.11. The latter shows the dynamic surface tensions of blood serum as measured by the maximum bubble pressure (filled symbols) and drop shape techniques (open symbols). It becomes evident that both methods complement each other perfectly when the data from the MPT2 studies are plotted as a function of /efi- The results impressively demonstrate that during the radiotherapy process the dynamic surface tension parameters return to the normal values (2), i.e. approach those characteristic of healthy females from the respective control group. 

When one applies an external flow to the microemulsion system, its mechanical response is deeply affected by its internal structure. Using a single-order-parameter time-dependent Ginzburg-Landau (TDGL) model, Mundy et al. have investigated rheological properties of microemulsions theoretically [2]. In their model, the order parameter represents the concentration difference between oil and water, and the presence of surfactants is taken into account through the surface tension parameter. Their work has been extended by Patzold and Dawson, and it was shown that the microemulsions behave in an essentially non-Newtonian manner [3]. 

In addition, some interesting conclusions can be mentioned. Panayiotou s (2014) surface tension parameters (acid and base) for water, based on PSPs, are identical, in agreement to the original van Oss-Good... 

Table 6.2 Surface tension parameters (in mJ m of some liquids and polymers [23, 32, 39]...

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