Phase diagrams ratios

When oil and gas are produced simultaneously into a separator a certain amount (mass fraction) of each component (e.g. butane) will be in the vapour phase and the rest in the liquid phase. This can be described using phase diagrams (such as those described in section 4.2) which describe the behaviour of multi-component mixtures at various temperatures and pressures. However to determine how much of each component goes into the gas or liquid phase the equilibrium constants (or equilibrium vapour liquid ratios) K must be known. 

Imhof A and Dhont J K G 1995 Experimental phase diagram of a binary oolloidal hard-sphere mixture with a large size ratio Phys. Rev. Lett. 75 1662-5... 

Colloidal crystals . At the end of Section 2.1.4, there is a brief account of regular, crystal-like structures formed spontaneously by two differently sized populations of hard (polymeric) spheres, typically near 0.5 nm in diameter, depositing out of a colloidal solution. Binary superlattices of composition AB2 and ABn are found. Experiment has allowed phase diagrams to be constructed, showing the crystal structures formed for a fixed radius ratio of the two populations but for variable volume fractions in solution of the two populations, and a computer simulation (Eldridge et al. 1995) has been used to examine how nearly theory and experiment match up. The agreement is not bad, but there are some unexpected differences from which lessons were learned. 

Before comparing these predictions regarding the critical point with experimental results, we may profitably examine the binodial curve of the two-component phase diagram required by theory. The following useful approximate relationship between the composition V2 of the more dilute phase and the ratio y = V2/v2 of the compositions of the two phases may be derived (see Appendix A) by substituting Eq. (XII-26) on either side of the first of the equilibrium conditions (1), using the notation V2 for the volume fraction in the more dilute phase and V2 for that in the more concentrated phase, and similarly substituting Eq. (XII-32) for fX2 and y,2 in the second of these conditions ... 

Fig. 123.—(a) Phase diagram calculated for three-component systems consisting of nonsolvent [1], solvent [2], and polymer [3] taking Xi==X2=l and Xz equal to 10 (dashed curve), 100 (solid curve), and °° (dotted curve) xi2 = xi3 = 1.5 and X23 =0. All critical points (O) are shown and tie lines are included for the xs = 100 curve. (Curves calculated by Tompa. ) (b) The binodial curve for a 3 = 100 and three solvent ratio lines. The precipitation threshold is indicated by the point of tangency X for the threshold solvent mixture. 

Figure 5.8 Clear glasses are confined to a narrow central compositional range at the centre of the phase diagram where the Al Oj/CaF ratio lies in the region 1 1 by mass and the SiOj/AljOj ratio exceeds 1-33 1 (Hill Wilson, 1988a).

As an example of binary clusters for magnetic applications, we present the study performed on Ni-Co alloy [78]. The Co-Ni phase diagram was investigated by performing sequential ion implantation in silica of Co and Ni at the same energy of ISOkeV (Rp 150nm) but with different fluences in order to have a constant total Co+Ni fluence (15 x lO ions/cm or 30 x 10 ions/cm ). For the 1 1 Co Ni ratio, we also performed sequential implants at... 

This work raises some interesting issues. The first is that the stoichiometry of a complex is not necessarily the most obvious. For example, it was reported initially that phthalic acid formed a 2 1 complex with alkoxystil-bazole [34], when in fact a careful study carried out by constructing a binary phase diagram (Fig. 11) revealed the complex to have a 1 1 ratio of the two components [35]. The reluctance of the system to form the more obvious 2 1 complex may relate to the presence of intramolecular hydrogen bonding or could even relate to the change in the pfCa of the second acid proton on com-plexation. 

The topological transformations in an incompatible blend can be described by the dynamic phase diagram that is usually determined experimentally at a constant shear rate. For equal viscosities, a bicontinuous morphology is observed within a broad interval of the volume fractions. When the viscosity ratio increases, the bicontinuous region of the phase diagram shrinks. At large viscosity ratios, the droplets of a more viscous component in a continuous matrix of a less viscous component are observed practically for all allowed geometrically volume fractions. 

Assume that the cations build up a perfect sodium chloride structure matrix. The formula must be expressed as (Mg, Al)10Ov To make sure that this formula is in agreement with the measured ratio of MgO and A1203 represented on the phase diagram use the following procedure ... 

Titanium disulfide, 25 57, 58 Titanium disulfide electrodes sloping discharge curve, 3 414 Titanium esters, 25 1 Titanium fluorides, 25 47-49 Titanium halides, 25 47-55 Titanium hydride, 13 626 Titanium hydrides, 25 5 Titanium-hydrogen system, 25 3-5 phase diagram for, 25 5 Titanium iodides, 25 54-55 Titanium/isopropoxy/nitrilotriethoxy ratio, 25 93... 

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