Phase boundary separator

We represent the phase boundary separating this electrode and the solution containing the other redox species by a single vertical line a ... 

It is interesting to note that the coordinate system utilized throughout this work (and also throughout the majority of the literature on metal oxidation [10]) is not strictly stationary relative to a laboratory coordinate system. The origin x = 0 is always chosen to be at the phase boundary separating the parent metal from the first oxide layer and this phase boundary moves (relative to the center of mass of the parent metal) as layers of the parent metal are consumed in the metal oxidation reaction. Similarly, xt — 0 always occurs at the phase boundary separating layer i — 1 from layer i. 

Each of the four cases delineated [(ci), (cv), (ai), and (av)] is developed individually in such a way that it is self-contained. Each theoretical development is preceded by a formulation of the relevant equations for the defect solid-state reactions [63, 64] occurring at the phase boundaries separating the oxides. That is, balanced chemical equations involving... 

The binodal curves (phase boundary) separate the one- and two-phase regions. Below the binodal cnrves are two-phase regions, and above the curves is a single-phase region. At the plait point of the binodal cnrve, all phase compositions are equal. The right plait point is nsnally located very close to the oil apex, and the left plait point is nsnally located very close to the water apex. In a two-phase region, the compositions of phases in eqnilibrium are connected with tie lines, along which may be found all possible proportions of the two phases, as explained in Example 7.1. Before that, we first need to review the lever rale. 

Along the phase boundary separating ice and water - the liquid-solid freezing curve - the number of phases present, solid and liquid, is two (P = 2), so, from Equation (S1.2), F = 1. Thus, this phase boundary (and aU phase boundaries in a one-component system) is characterised by one degree of freedom. This means that one variable, either pressure or temperature, can be changed and two phases in equilibrium can still be found. However, the two variables are closely connected. If the pressure is changed then the temperature must also change, by exactly the amount specified in... 

Fig. 6. Phase boundary separating pure lattice gas region from coexistence region of lattice gas and condensed phase in 7-0-diagram for AgAV(llO) [85Koll].

Gas hydrate forms wherever appropriate physical conditions exist—moderately low temperature and moderately high pressure—and the materials are present—gas near saturation and water. These conditions are found in the deep sea commonly at water depths greater than about 500 m or somewhat shallower depths (about 300 m) in the Arctic, where bottom-water temperature is colder. Gas hydrate also occurs beneath permafrost on land in arctic conditions, but, by far, most natural gas hydrate is stored in ocean floor deposits. A simplified phase diagram is shown in Fig. 2A, in which pressure has been converted to water depth in the ocean (thus, pressure increases downward in the diagram). The heavy line in Fig. 2A is the phase boundary, separating conditions in the temperature/pressure field where methane hydrate is stable to the left of the curve (hatched area) from conditions where it is not. In Fig. 2B, some typical conditions of pressure and temperature in the deep ocean were chosen to define the region where methane hydrate is stable. The phase boundary indicated is the same as in Fig. 2A, so methane hydrate is stable... 

Figure 3. Phase boundary separating the isotropic and nematic phases in the cooperative limit X 0. The area to the right of the solid line and below s = 1 represents the region of induced rigidity.

Cell notation (13.2) Shorthand notation for an electrochemical cell that shows the electrodes, gases, and solutions in the cell reaction as well as the phase boundaries separating them. 

Fig. 80. Miscibility/composition diagrams for ternary PCL (low molecular weight)/SAN-15/SMA-14 blends at different temperatures, molecular weights defined in text the solid line is a suggested phase boundary separating miscible (larger dots) and immiscible (smaller dots) mixtures taken from [149]...

Reachon between compounds A and B can take place only if the two phases PI and P2 are brought into contact with each other so that compoimd A in phase PI will move to phase P2 crossing the phase boundary separating the two phases (Figure 2.28). 

For higher incommensurability parameter ((and/or asymmetric fourth order terms 5mi> <2) [84] a new phase boundary separating two SmA2 phases appears (Fig. 6 b). The two SmA2 phases are distinguished by different values of the amplitudes of the order parameters and X2 and therefore of the wavevector kg. For Xj >X2, ko is of order k] (i.e. the smectic period is close to l =dxl<2l) and the modulus Xj is much... 

Radiometric Titration—Titrimetric methods, in which the endpoint is estimated by means of radiometric measurements, are termed radiometric titrations. In order to follow the course of the reaction the titration must take place in such a manner that the radioactivity, originally present in only titrand, titrant, or indicator, crosses a phase boundary separating the radioactive reagent from the products. Methods have been devised using solid-liquid, liquid-liquid, and solid-gas transfers. The theory and practice of radiometric titrations are discussed, with reference to many examples, by Braun and Tolgyessy in their comprehensive monograph. 

More than one phase can coexist within the system at equilibrium. When this phenomenon occurs, a phase boundary separates the phases from each other. One of the major topics in chemical thermodynamics, phase equilibrium, is used to determine the chemical compositions of the different phases that coexist in a given mixture at a specified temperature and pressure. 

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