Ternary systems main types

The thiomolybdites are a class of molybdenum-sulfur compounds which contain molybdenum in a low oxidation state, usually +3. Two main types of such materials exist. The first type has the formula MMoS2 where M is a monovalent cation, usually an alkali metal. The second type has the formula MMo2S4 where M is a divalent cation, usually a transition metal. There are other thiomolybdite species, of composition other than that described above, which have been identified in ternary phase studies involving the M-Mo-S system (M = a transition element), but these have not been well characterized. 

From the results of this investigation five main types of phase diagrams were constructed for ternary systems of the type described above. These are presented below in a schematic form. 

If the alcohol in the ternary soap system is replaced by a fatty acid, yet another type is obtained. Here, as in the previous main type, there are the five mesophases B, C, D, E, and F and the two regions, Lh and L2, with homogeneous solutions. In this case, however, no water is needed to make soap and fatty acid mutually soluble. This is illustrated in Figure 28, which shows the phase equilibrium in the sodium caprylate-caprylic acid-water system. Here L2 extends to the caprylate-caprylic acid axis, and in the other direction far into the water comer. This is obviously caused by the ability of the soap and fatty acid to form molecular compounds with one another—the familiar acid soaps, which can also exist in the solid crystalline form. 

Solubilization, Microemulsions and Emulsions. - Micellar solutions with both normal (Li) and reverse (L2) curvature, e.g. o/w and w/o type systems, can be swollen by oil and water to obtain water/oil/amphiphile ternary or pseudoternary systems. These systems have been widely used as solubilizing media for structural investigations of the immobilized solubilizate (a protein for instance), for drug delivery systems, and also for reaction media, (micellar catalysis). Ternary systems based on water, oil, and amphiphile mixtures can form a variety of Li and L2 monophasic regions. When these systems form isotropic solutions spontaneously, they are termed microemulsions. The formation of a microemulsion is related mainly to a substantial decrease of the interfacial tension (Yo/w) at the oil-water interface, due to the amphiphilic molecules located at the polar-apolar interface. This occurs in agreement with the typical equation ... 

A reaction scheme is proposed by [1969Jel] for the metastable system. Three U type ternary reactions have been reported. The corresponding ternary reactions mainly based on [1969Jel] are reported in Table 4. The reaction scheme regarding the stable and the metastable ternary reactions is depicted in Figs. 4a and 4b... 

In the experiments, various types of solvents are commonly used, so that we should consider a mixture R A/ /R Bg /S, where S denotes the solvent. Extension of the following theoretical consideration to such ternary systems is straightforward as long as the solvent is inactive. Therefore, for simplicity, we will mainly confine the discussion to binary systems. 

The experimental investigations were and are the main sources of information about phase behavior in ternary systems. In the beginning of the twentieth century Smiths (1910, 1913, 1915) using the topological method and available experimental information has considered 12 versions of complete phase diagrams with various types of fluid phase behavior and solid phase transformations. But it was not a systematic classification. 

Similarly to the phase diagrams for binary systems, the main types for fluid phase diagrams of ternary mixtures should not have an intersection of critical curves and inunis-cibUity regions with a crystallization surface in them. Combination of four main types of binary fluid phase behavior la, lb, Ic and Id (Figure 1.2) for constituting binary subsystems gives six major classes of ternary fluid mixtures with one volatile component, two binary subsystems (with volatile component) complicated by the immiscibility phenomena and the third binary subsystem (consisted from two nonvolatile components) of type la with a continuous solid solutions. These six classes of ternary fluid mixtures can be referred as ternary class I (with binary subsystems Ib-lb-la), ternary class II (with binary subsystems Ic-lc-la), ternary class III (with binary subsystems Id-ld-la), or ternary class IV (with binary subsystems Ib-ld-la), ternary class V (with binary subsystems Ib-lc-la) and ternary class VI (with binary subsystems Ic-ld-la). 

Schomacker compared the use of nonionic microemulsions with phase transfer catalysis for several different types of organic reactions and concluded that the former was more laborious since the pseudo-ternary phase diagram of the system had to be determined and the reaction temperature needed to be carefully monitored [13,29]. The main advantage of the microemulsion route for industrial use is related to the ecotoxicity of the effluent. Whereas nonionic surfactants are considered relatively harmless, quaternary ammonium compounds exhibit considerable fish toxicity. 

The increase in isotacticity seems to be essentially connected to the decrease of the initial rate, as practically no change in the isotacticity index with polymerization time was detected. Moreover, while the atactic productivity decreases monotonically with the EB/TEA ratio in both systems, the isotactic productivity has a more complex behavior with the binary catalyst it remains almost unchanged up to EB/TEA s 0.25 and then falls, whereas with the ternary catalyst it increases up to EB/TEA 0.2 and then rapidly drops. On the grounds of these results, Spitz suggested that the reversible adsorption on the catalytic surface of the TEA EB complex (which is supposed to be very fast) changes the non specific centers into stereospedfic, though less active, centers, while the slower adsorption of free EB reversibly poisons both types of sites. The differences between the binary and the ternary catalysts would arise mainly from the presence, in the latter, of a larger number of potential stereospecific sites. 

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