Oxide phases phase diagrams

Plutonium oxides. The phase diagram of the plutonium-oxygen system is shown in Fig. 9.2. The observed compounds are the stoichiometric PujOj and PUO2 and the nonstoichiometric PuOj.sj and Pui. i. PuO has also been shown to exist, but only under extreme conditions. No oxide of higher oxidation state than PuOs has been formed. 

Often the catalyst is bonded or compounded with silica, and the presence or absence of silica appears to have little effect on the reactions. Likewise, results are reported both with and without phosphorus which do not differ greatly. Studies of the effect of the Bi/Mo ratio have been made in efforts to find the reasons for the markedly different catalytic behavior of bismuth molybdate, so-called, relative to bismuth and molybdenum oxides. The phase diagram for this system was published by Belyaev and Smolyaninov 144), and was confirmed and refined by... 

Avella, M., Martuscelli, E. Poly-d(-)(3-hydroxybutyrate)/poly(ethylene oxide) blends phase diagram, thermal and crystallization behavior. Polymer 29(10), 1731-1737 (1988)... 

Fig. 6.5 Lead oxide-titanium oxide phase equilibrium diagram. 

E. A. Brandes and R. E. Flint, Manganese Phase Diagrams, The Manganese Centre, Paris, 1980 L. B. Pankratz, Thermodynamic Properties of Elements and Oxides, Bull. 672, U.S. Bureau of Mines, Washington, D.C., 1982. 

Fig. 6. Phase diagram for three crystalline and two Hquid forms of phosphoms(V) oxide. To convert kPa to mm Hg, multiply by 7.5.

Table 1 fists the more important physical properties of calcium carbide. Additional properties are given in the literature (1). Figure 1 gives the phase diagram calcium carbide—calcium oxide for pure and technical grades. 

Fig. 1. Calcium carbide—calcium oxide phase diagram using A, pure CaC2, and B, technical-grade...

Take the silica-alumina system as an example. It is convenient to treat the components as the two pure oxides SiOj and AI2O3 (instead of the three elements Si, A1 and O). Then the phase diagram is particularly simple, as shown in Fig. 16.6. There is a compound, mullite, with the composition (Si02)2 (Al203)3, which is slightly more stable than the simple solid solution, so the alloys break up into mixtures of mullite and alumina, or mullite and silica. The phase diagram has two eutectics, but is otherwise straightforward. 

Fig. 7.80 A schematic thermodynamic phase stability diagram for the A-C-O system, showing three reaction paths. Paths 2 and 3 are only possible if gaseous diffusion in pores in the oxide product results in a carbon activity increase through the scale, as shown in Fig. 7.81 (after...

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 ... 

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