Phase diagram analysis

Phase Transformation and Phase Diagram Analysis During Preparation... 

Phosphides. Zirconium forms several phosphides ZrP [39318-19-9] 2 [ 12037-80-8] and ZrP g [12066-61 -4]-, they are part of the Zr—P phase diagram (137). The solubiUty of phosphoms in zirconium metal is low, ca 50 ppm, and at higher concentrations it collects as separate globules at the metal grain boundaries. Analysis indicates that this material is Zr P. 

Phase diagrams are mostly determined by thermal analysis. We now discuss one-component systems to show how it works. The more complicated diagrams for binary, ternary or quaternary alloys are determined by the same method. 

FIG. 14 Phase diagram of the quantum APR model in the Q -T plane. The solid curve shows the line of continuous phase transitions from an ordered phase at low temperatures and small rotational constants to a disordered phase according to the mean-field approximation. The symbols show the transitions found by the finite-size scaling analysis of the path integral Monte Carlo data. The dashed line connecting these data is for visual help only. (Reprinted with permission from Ref. 328, Fig. 2. 1997, American Physical Society.)... 

The equlibrium between the bulk fluid and fluid adsorbed in disordered porous media must be discussed at fixed chemical potential. Evaluation of the chemical potential for adsorbed fluid is a key issue for the adsorption isotherms, in studying the phase diagram of adsorbed fluid, and for performing comparisons of the structure of a fluid in media of different microporosity. At present, one of the popular tools to obtain the chemical potentials is an approach proposed by Ford and Glandt [23]. From the detailed analysis of the cluster expansions, these authors have concluded that the derivative of the excess chemical potential with respect to the fluid density equals the connected part of the fluid-fluid direct correlation function (dcf). Then, it follows that the chemical potential of a fluid adsorbed in a disordered matrix, p ), is... 

It was shown some time ago that one can also use a similar thermodynamic approach to explain and/or predict the composition dependence of the potential of electrodes in ternary systems [22-25], This followed from the development of the analysis methodology for the determination of the stability windows of electrolyte phases in ternary systems [26]. In these cases, one uses isothermal sections of ternary phase diagrams, the so-called Gibbs triangles, upon which to plot compositions. In ternary systems, the Gibbs Phase Rule tells us... 

Taking into account the usual conditions of the hydrogel application, we shall limit our discussion to that part of the phase diagram which depicts the swollen gel and touch upon the collapse only in passing since a detailed analysis of this phenomenon is given by Tanaka [96, 97], Ilavsky [19, 98], and Khokhlov [99],... 

The phase diagram of the Li-Au system reveals a great deal of complexity, with separate intermetallic phases being formed based on thermal analysis supported by x-ray diffraction at specific compositions. Annealing, sometimes over long time periods, has been undertaken in some cases. 

The Ca-Cu system has been reexamined using thermal analysis and x-ray diffraction methods an independent study of the CaCuj-Cu section has also been completed. The resultant phase diagram, although similar to that in ref. 3 at the Cu-rich end, differs markedly for Ca-rich alloys. Supporting evidence for the modifications has been obtained from the Ca-Mg-Cu ternaiy system. Three intermediate compounds are formed in the system CaCuj (950 C) melts congruently, whereas CajCu (488 C) and CaCu (567°C) are formed in peritectic reactions. Single-crystal x-ray diffraction studies verify the stoichiometry of CajCu and examine the polymorphism of CaCu. ... 

The Sr-Cu system has been critically assessed. The most recent phase diagram, determined by combining differential thermal analysis and x-ray diffraction techniques, contains two intermediate compounds, both of which form in peritectic reactions, SrCu (588°C) and SrCu, (845°C) SrCu has also been prepared for independent structural analysis-. ... 

Two versions of the Ba-Cd phase diagram are very similar and, but for some minor differences in the critical point parameters, differ only in the stoichiometry of the compound at 17 at% Ba-Ba2Cd9 or BaCd . Since ref. 5 includes a structural analysis of the intermediate compounds, this phase diagram is recommended. There are five intermediate compounds in the system. Four of these melt congruently, BaCd (SSS C), BaCdj (642°C), Ba2Cd, (620°C) and BaCd (672°C) the other, BajCd (409°C), is formed in a peritectic reaction. The existence of Ba2Cd BaCd, BaCdj, and BaCd], has been verified in separate crystallographic studies. 

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