Ternary eutectic

The phase diagram of such a system has four planes. The plane pc(A) is the vertical projection of the plane of primary crystallization of the compound A, plane pc(B) represents the plane of primary crystallization of the component B, and the plane pc(C) refers to the primary crystallization of compound C. Finally, the plane pc(AB) is the projection of the plane of primary crystallization of compound AB. In the case of the congruently melting compound AB its figurative point lies inside the plane of the primary crystallization of this compound. In comparison with the simple eutectic ternary system a new boundary line, Ctj - Ct2, which represents the common crystallization of compounds C and AB, will arise. The joint AB-C divides the ternary system A-B-C into two simple... 

In the case of a mixture shown on Figure 3.32 by the figurative point X3, the situation is similar as in a simple eutectic ternary system. Starting with the crystallization of component C, the composition of the melt moves up to the point 5, where the component A4B begins to crystallize. At the ensuing cooling, the composition of the melt moves on the boundary line Pt—Ct up to the ternary eutectic point, where also component B crystallizes until the whole system solidifies. 

The phase diagram has four planes pc(A), pc(B), pc(C), and pc(ABC), representing the vertical projections of the planes of the primary crystallization of the individual compounds. The figurative point of the ternary compound ABC lies inside the ternary system A-B-C. There are three boundary lines etj -et2, et2 and etj -etj representing the common crystallization of compounds B, C, and A with AB, respectively. The joints of the figurative point ABC with the apexes of the concentration triangle divide the phase diagram into three simple eutectic ternary systems A-ABC-B, B-ABC-C, and A-ABC-C. The points, where the individual joins of ABC with the apexes cross the boundary lines, form the summits of the boundary lines. 

Bowen [148] obtained crystalline acrylic monomers, thus making it possible to purify them. By the reaction of 2-hydroxyethyl methacrylate with the three isomers of benzene dicarboxylic acid—phthalic, isophthalic, and terephthalic acid—adequate esters are obtained mixed in various proportions, these make an eutectic ternary mixture that can play the role of the organic phase in DARs. The only shortcoming of these monomers is that they show a tendency to acquire color in the presence of the polymerization accelerators (N,N-dimethyl-p-toluidine). Isomer dimethacrylates (o-, m-, and p-)bis(hydroxyethyl)-dihydroxybenzen-... 

Eutectics melting at about —30, —47, and —40° C are formed in the binary systems, cesium—sodium at about 9% sodium, cesium—potassium at about 25% potassium, and cesium—mbidium at about 14% mbidium (34). A ternary eutectic with a melting point of about —72°C has the composition 73% cesium, 24% potassium, and 3% sodium. Cesium and lithium are essentially completely immiscible in all proportions. 

Safonov et al. 330) also investigated the In-Te-I system by DTA and X-ray diffraction. The system contains three, congruently melting, ternary compounds InTel, Inl3-2Tel4 and InIs-STel, of which the latter two are out of the scope of this review. InTel melts congruently at 475°C. It forms part of the quasibinary cuts In Tea-Inla and Inl-Te, where the sections InTel-In Tes, InTel-Inia, InTel-Ini, and InTel-Te are all of the eutectic type (80). 

Figure 1. Part of the Na-K-Cs phase diagram showing the ternary eutectic at -78 C.

Low-temperature solid-state synthesis is preferred in most cases, where appropriate, for obvious reasons such as energy and cost economy and process safety or for critical concerns regarding the accessibility of compounds that are stable only at low temperatures or non-equilibrium phases, i.e., compounds thermodynamically unstable with respect to the obtained phase (e.g., a ternary instead of binary phase). The use of low-temperature eutectics as solvents for the reactants, hydrothermal growth... 

Stable, conductive electrodes would also be a problem. Preliminary experiments, were carried out in a cell, using simulated flue gas nearly identical to that shown in Fig. 24. In these tests, the membranes were hot-pressed from mixed powders of electrolyte (ternary eutectic of [Na, Li, K]2 S04) with LiA102 as matrix. The electrodes were constructed of cold-pressed Li20-9Cr203, partially sintered to give a highly-porous gas-diffusion structure. The tests were encouraging up to 50% of the S02 was removed from the simulated flue gas with the application of current. Simultaneously, a stream of concentrated S03 and Oz was evolved at the anode. 

Figure 24 shows the ternary phase diagram (solubility isotherm) of an unsolvated conglomerate that consists of physical mixtures of the two enantiomers that are capable of forming a racemic eutectic mixture. It corresponds to an isothermal (horizontal) cross section of the three-dimensional diagram shown in Fig. 21. Examples include A-acetyl-leucine in acetone, adrenaline in water, and methadone in water (each at 25°C) [141].

In the present case there are no ternary invariant equilibria in the system, partly due to the complete solid solubility of the A-B system. In a ternary system composed from three binary eutectic sub-systems, three univariant lines would meet in a ternary eutectic equilibrium ... 

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