Binary Phase Systems

The fracture toughness of t -zirconia was found to be less ( 4MN-m ) than that of t-zirconia ( 7 MN The maximum Kjc value was obtained in a product 

2001) binary phase diagram Zr02-Sc203. Reprinted with permission from Wiley-Blackwell, Oxford, UK. 

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Resorcinol (22) is readily converted to 2,4-dinitrosoresorcinol (23) in quantitative yield by slowly adding an aqueous solution containing two mole equivalents of sodium nitrite to a solution of resorcinol that has been acidified with two mole equivalents of sulfuric acid. The 2,4-dinitrosresorcinol (23) from this process can be oxidized to 2,4-dinitroresorcinol (24) with a binary phase system of toluene and dilute nitric acid at -5 Treatment of either 2,4-... 

Heating a polymer-solvent a binary phase system... 

Provide graphs analogous to Figs. 3.16.2-3.16.5, which show how the entropy of mixing ASm/R varies with temperature in the region where the binary phase system is stable. 

More precisely, the scattering invariant for an ideal binary phase system without nano-voids is expressed by Eq. (11.10) (Glatter and Kratky 1982) ... 

Ideal Binary Phase System with Both Solids Completely Soluble in One Another... 

Beaudry and Spedding (1974) have studied the binary phase system between ytterbium metal, which is normally divalent, and lutetium metal, which is trivalent The Yb-Lu system is representative of the systems between ytterbium and the rare earth metals that do not have a high temperature bcc form. 

A binary phase system that forms an intermetallic compound normally provides good adhesion because of the mutual attraction between atoms of different species. Examples of this type of system include Ti-Cu, Ni n, and Sn-Cu (Fig. 29) [105]. Intermetallic compound formation occurs during high-temperature process steps, and the consequences are usually undesirable, resulting in increased stress levels, impurity snowplowing, Kirkendall voids, and an increase in electrical resistance. These reactions must be controlled either by hmiting the amount of reactants available or by controlling the time and temperature of the reaction. 

Binary Alloys. Aluminum-rich binary phase diagrams show tliree types of reaction between liquid alloy, aluminum solid solution, and otlier phases eutectic, peritectic, and monotectic. Table 16 gives representative data for reactions in tlie systems Al—Al. Diagrams are shown in Figures 10—19. Compilations of phase diagrams may be found in reference 41. 

In conclusion, we have presented a new formulation of the CVM which allows continuous atomic displacement from lattice point and applied the scheme to the calculations of the phase diagrams of binary alloy systems. For treating 3D systems, the memory space can be reduced by storing only point distribution function f(r), but not the pair distribution function g(r,r ). Therefore, continuous CVM scheme can be applicable for the calculations of phase diagrams of 3D alloy systems [6,7], with the use of the standard type of computers. 

As an acidic oxide, SiOj is resistant to attack by other acidic oxides, but has a tendency towards fluxing by basic oxides. An indication of the likelihood of reaction can be obtained by reference to the appropriate binary phase equilibrium diagram. The lowest temperature for liquid formation in silica-oxide binary systems is shown below ... 

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. 

In many systems, both single-phase and polyphase behaviors are found in different composition ranges. Intermediate, as well as terminal, phases often have been found to have quite wide ranges of composition. Examples are the broad Zintl phases found in several of the binary lithium systems studied by Wen [29]. 

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. 

In the previous sections we have been concerned with high-pressure equilibria in systems containing one liquid phase and one vapor phase. We now briefly consider the effect of pressure on equilibria between two liquid phases. In particular, we are concerned with the question of how pressure may be used to induce miscibility or immiscibility in a binary liquid system. 

Second, Schneider s article reviews recent work (notably by Rowlinson, Kohn and co-workers) on phase relations in binary liquid systems where one of the components is much more volatile than the other (D1, D2, E3, M8, R9). Such systems may have lower critical solution temperatures for these systems, an increase in temperature (and, indirectly, pressure) causes precipitation of the heavy component, thereby providing a possible separation technique, e.g., for the fractionation of polymers. 

Figure 2. Partial Binary Phase Diagram for the CaO-CaCl2 System.

An example for a partially known ternary phase diagram is the sodium octane 1 -sulfonate/ 1-decanol/water system [61]. Figure 34 shows the isotropic areas L, and L2 for the water-rich surfactant phase with solubilized alcohol and for the solvent-rich surfactant phase with solubilized water, respectively. Furthermore, the lamellar neat phase D and the anisotropic hexagonal middle phase E are indicated (for systematics, cf. Ref. 62). For the quaternary sodium octane 1-sulfonate (A)/l-butanol (B)/n-tetradecane (0)/water (W) system, the tricritical point which characterizes the transition of three coexisting phases into one liquid phase is at 40.1°C A, 0.042 (mass parts) B, 0.958 (A + B = 56 wt %) O, 0.54 W, 0.46 [63]. For both the binary phase equilibrium dodecane... 

There seem to be many binary metallic systems in which there are phases of this sort. In the sodium-lead system there are two such phases. One of them, based on the ideal structure Na3Pb, extends from 27 to 30 atomic percent lead, with its maximum at about 28 atomic percent lead and the other, corresponding to the ideal composition NaPb3, extends from 68 to 72 atomic percent lead, with maximum at about 70 atomic percent. The intensities of X-ray reflection have verified that in the second of these phases sodium atoms occupy the positions 0, 0, 0, and the other three positions in the unit cell are occupied by lead atoms isomorphously replaced to some extent by sodium atoms (Zintl Harder, 1931). These two phases are interesting in that the ranges of stability do not include the pure compounds Na8Pb and NaPb3. 

W. G. Moffatt, The Handbook of Binary Phase Diagrams, General Electric Co., Schenectady, NY, 1977. Lxxiseleaf system in three volumes with regular updating. Contains excellent index to material contained in refs. 1-3. 

Almost all of the rare-earth metal/rare-earth metal tri-iodide systems, R/RI3, contain binary phases with the rare-earth element in an oxidation state lower than -1-3 ( reduced rare-earth metal iodides) [3, 7, 10-13]. More common is the oxidation state -i-2. Elements that form di-iodides RI2 are illustrated in Fig. 4.1. 

The binary compounds of palladium and platinum show a higher diversity of structures than found for the Rh-Ir and Ru-Os systems. Aside from several other reported binary phases, four general families can be distinguished ... 

OC10H21)], in which rearrangement does not occur. All the mixtures studied display liquid crystal behavior with improved properties with respect to the pure components. A representative binary phase diagram and their corresponding DSCtraces are presented in Figures 8.24 and 8.25 respectively, and reveal the eutectic nature ofthese systems. 

Data for the hydrogen sulfide-water and the methane-n-hexane binary systems were considered. The first is a type III system in the binary phase diagram classification scheme of van Konynenburg and Scott. Experimental data from Selleck et al. (1952) were used. Carroll and Mather (1989a b) presented a new interpretation of these data and also new three phase data. In this work, only those VLE data from Selleck et al. (1952) that are consistent with the new data were used. Data for the methane-n-hexane system are available from Poston and McKetta (1966) and Lin et al. (1977). This is a type V system. 

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