Single-phase region

TABLE 23. Thermodynamic Properties of Freon-21 in the Single-Phase Region 7 =303,15 K  

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DEF. When the constitution point lies in a single-phase region, the alloy consists of a single, homogeneous, phase. Its composition must (obviously) be that of the alloy. The phase composition and the alloy composition coincide in single-phase fields. 

The high-pressure study on the Ti-H alloys showed stress-strain properties are not the only ones which are affected by pressure, but phase equilibria are also strongly dependent on this parameter . A new ( -phase and a corresponding single phase region in the isobaric T — C section of the T — P — C phase diagram appear in the... 

The general thermodynamic treatment of binary systems which involve the incorporation of an electroactive species into a solid alloy electrode under the assumption of complete equilibrium was presented by Weppner and Huggins [19-21], Under these conditions the Gibbs Phase Rule specifies that the electrochemical potential varies with composition in the single-phase regions of a binary phase diagram, and is composition-independent in two-phase regions if the temperature and total pressure are kept constant. 

Because of the interest in its use in elevated-temperature molten salt electrolyte batteries, one of the first binary alloy systems studied in detail was the lithium-aluminium system. As shown in Fig. 1, the potential-composition behavior shows a long plateau between the lithium-saturated terminal solid solution and the intermediate P phase "LiAl", and a shorter one between the composition limits of the P and y phases, as well as composition-dependent values in the single-phase regions [35], This is as expected for a binary system with complete equilibrium. The potential of the first plateau varies linearly with temperature, as shown in Fig. 2. 

For larger values of fx the density of the film may, for some systems, increase somewhat before the second layer is initiated. That is, there may be a narrow single-phase region which extends from N=Ni to and... 

FIG. 5 Order parameter for disperse pseudophase water (percolating clusters versus isolated swollen micelles and nonpercolating clusters) derived from self-diffusion data for brine, decane, and AOT microemulsion system of single-phase region illustrated in Fig. 1. The a and arrow denote the onset of percolation in low-frequency conductivity and a breakpoint in water self-diffusion increase. The other arrow (b) indicates where AOT self-diffusion begins to increase. 

Yadigaroglu, G., and A. E. Bergles, 1972, Fundamental and Higher-Mode Density-Wave Oscillation in Two-Phase Flow The Importance of Single Phase Region, Trans. AS ME, J. Heat Transfer 94 189-195. (6)... 

C. Each Figure shows titration data for compositions inside of the miscibility gap (where the "curve" is linear), as well as enthalpies in a single-phase region. Data from the literature are also shown for comparison with the present results (13-161. Table I shows values of the compositions of the aqueous and amphiphilic phases for n-butanol/water at 30.0 and 55.0 °C and for n-butoxyethanol/water at... 

Figure 2.12a. Building blocks of binary phase diagrams examples of single-phase (two-variant) and two-phase (mono-variant) fields. In the figure the indication is given of the phases existing in the various fields and respectively of their number. The phase equilibrium composition in the two-phase fields is defined by the boundary (saturation) lines of the single-phase regions. (Pt), (Ag),...

Figure 2.29. Isothermal sections of ternary phase diagrams (a) Al-Er-Mg system at 400°C, Saccone et al. (2002) and, (b) Al-Cu-Ti system at 540°C from Villars et al. (1995). A number of single-phase regions (dark grey) may be noticed, both extending from binary compounds and as ternary intermediate phases (r) in the Al-Er-Mg system and the four phases Tj t2 t3 and t4 in the Al-Cu-Ti system. The three-phase fields are marked by an asterisk, in the Al-Er-Mg system a few tie-lines are indicated in the two-phase fields.

Fig. 8.7 Coulometric titration curve for the addition of Li to Sb and Bi. The plateaux indicate two-phase regions whereas the voltage drops correspond to single phase regions.

In conclusion, the combination of thermodynamic measurements over single phase and multiphase regimes and kinetic measurements within single phase regions provides a comprehensive overall picture of the electrode performance. The extracted thermodynamic and kinetic data may be converted into the rate constants that describe the growth of new phases in the electrode during the course of discharge. 

The aim of the experiment is to determine the microemulsion (i.e. clear, single-phase) region for the three components already discussed and map out the results on a triangular phase diagram. The microemulsion region is determined by making up a series of mixtures in lOcm stoppered Erlenmeyer flasks with compositions that span the anticipated range. The procedure is to start with a volume of about 2cm of oil... 

Figure 6 Single-phase region (open circles) for the 80 K superconductor in the Bi-Sr-Ca-Cu-O system (39).

The other single phase region is the liquid L. In addition to the two phase a+0 region, there are two other two phase regions L + a and L + 0. Just as in the isomorphous diagram the solidus and liquidus lines are connected by tie-lines of constant temperature. In a like manner, the a + 0 region is also considered to possess tie-lines joining the two solid-solution or solvus curves. 

Any point within a single-phase region (diamond phase field, where both temperature and pressure can be changed independently without creating or destroying the phase. No equilibrium exists here—there is only one phase. 

Carbon is soluble to varying degrees in each of these allotropic forms of iron. The solid solutions of carbon in a-Fe, y-Fe, and <5-Fe are called, respectively, ferrite, austenite, and 8-ferrite. So, for example, the single-phase region labeled as y in... 

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