Phase pseudobinary

Shaltiel, D., Jacob, I., Davidov, D. (1977) Hydrogen absorption and desorption properties of AB2 Laves-phase pseudobinary compounds J.Less-common metals 53, 117-131. 

Figure A2.5.30. Left-hand side Eight hypothetical phase diagrams (A through H) for ternary mixtures of d-and /-enantiomers with an optically inactive third component. Note the syimnetry about a line corresponding to a racemic mixture. Right-hand side Four T, x diagrams ((a) tlirough (d)) for pseudobinary mixtures of a racemic mixture of enantiomers with an optically inactive third component. Reproduced from [37] 1984 Phase Transitions and Critical Phenomena ed C Domb and J Lebowitz, vol 9, eh 2, Knobler C M and Scott R L Multicritical points in fluid mixtures. Experimental studies pp 213-14, (Copyright 1984) by pennission of the publisher Academic Press.

A.J. Schwartz and L.E. Taimer, Transformadons and phase relations in the TiPd-TiCr pseudobinary... 

Stannite is the most common tin sulfide mineral in the ore deposits associated with tin mineralization. This mineral sometimes contains appreciable amounts of zinc, together with iron. Several workers have suggested that the zinc and iron contents of stannite are related to temperature. With respect to the study of the phase relationships in the pseudobinary stannite-kesterite system. Springer (1972) proposed zincic stannite as a possible geothermometer mainly based on the chemical compositions of the two exsolved phases (stannite and kesterite). Nekrasov et al. (1979) and Nakamura and Shima (1982) experimentally determined the temperature dependency of iron and zinc partitioning between stannite and sphalerite. 

Figure 7.3 depicts phase stability relations in the pseudobinary system CaMgSi206-CaAl2Si208 (diopside-anorthite). The original study of Bowen (1915) described crystallization behavior identical to the previously discussed case a mechanical mixture (Di-An) in equilibrium with a completely miscible melt. A later investigation (Osborn, 1942) showed that the system is not strictly binary... 

Figure 7,6 Phase stability relations in pseudobinary system NaAlSi30g-KAlSi30g, after Waldbaum and Thompson (1969). (A) High-T relations loop of metastable persistency of sanidine like a Roozeboom type III. (B) Expanded T-range with decreasing T, a solvus held opens downward.

Figure 2.18 Examples of isopleths and pseudobinary phase diagrams, (a) constant A/C (b) constant A. Reprinted, by permission, from F. N. Rhines, Phase Diagrams in Metallurgy. Copyright 1956 by McGraw-Hill Book Co.

Recall that we can take vertical slices of the ternary phase diagrams, as well as isothermal (horizontal) slices. If we take, for example, a slice that begins at the tenarite composition (CuO) and extends across to the hematite composition (Fc203), we would end up with a pseudobinary phase diagram, which, when plotted on the appropriate temperature-composition axes, would look like Figure 2.22. Note that the compound CuFc204 is present, here labeled as spinel (see Section 1.2.2.3), but there is much more phase and temperature information available to us. This is, in fact, how many metal oxide phase diagrams are presented. The most stable forms of the... 

Fig. 38. Liquidus surface in the Hg-Cd-Te system on the Hg-Cd-rich side of the HgTe-CdTe pseudobinary section. The liquidus temperature in degrees Celsius is plotted against the atom fraction of for fixed values of z that are shown along the right vertical axis. The composition of the liquid phase is written as (Hg , Cdz),Te, y. Experimental points shown as symbols. The single diamond point is for = 0.09. Arrows below each liquidus lines indicate where the atom fractions of Cd and are equal.

The metal-H or alloy-H system can be regarded as a binary or pseudobinary system, i.e. c = 2 in the phase rule. Figure 3.17 shows schematically the relation between H2 and solid phase composition H/M for various values of T, assuming two solid phases a and p. These phases correspond to the... 

This electronic explanation of the synergy between Co or Ni and Mo does not give any direct information on the structure of the active phase except that cobalt or nickel atoms should be bonded to molybdenum atoms through bridging sulfur atoms according to the molecular model used by the authors. The precise structure of this pseudobinary cluster is as yet unknown, but... 

The phases form part of pseudobinary systems between the copper(I) halide and selenium or tellurium, respectively. 

The thermodynamic quantity 0y is a reduced standard-state chemical potential difference and is a function only of T, P, and the choice of standard state. The principal temperature dependence of the liquidus and solidus surfaces is contained in 0 j. The term is the ratio of the deviation from ideal-solution behavior in the liquid phase to that in the solid phase. This term is consistent with the notion that only the difference between the values of the Gibbs energy for the solid and liquid phases determines which equilibrium phases are present. Expressions for the limits of the quaternary phase diagram are easily obtained (e.g., for a ternary AJB C system, y = 1 and xD = 0 for a pseudobinary section, y = 1, xD = 0, and xc = 1/2 and for a binary AC system, x = y = xAC = 1 and xB = xD = 0). 

Figure 25. Schematic of a pseudobinary phase diagram exhibiting a miscibility gap.

Vertical sections Vertical cuts through a ternary can be made at either a constant amount of one of the components or at a constant ratio of two components (Figure 6.7). These pseudobinaries differ from binary phase diagrams in that the tie... 

The experimental studies of three-component systems based on phase equilibria follow the same principles and methods discussed for two-component systems. The integral form of the equations remains the same. The added complexity is the additional composition variable the excess chemical potentials become functions of two composition variables, rather than one. Because of the similarity, only those topics that are pertinent to ternary systems are discussed in this section of the chapter. We introduce pseudobinary systems, discuss methods of determining the excess chemical potentials of two of the components from the experimental determination of the excess chemical potential of the third component, apply the set of Gibbs-Duhem equations to only one type of phase equilibria in order to illustrate additional problems that occur in the use of these equations, and finally discuss one additional type of phase equilibria. 

Fig. 25. T-X diagram of the pseudobinary join X-phase — Y-phase ( CuMo2S3 — FeMo4Sg) in weight per cent...

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