Temperature ternary solution

The steel will be considered to be an ideal ternary solution, and therefore at all temperatures a, = 0-18, Ani = 0-08 and flpc = 0-74. Owing to the Y-phase stabilisation of iron by the nickel addition it will be assumed that the steel, at equilibrium, is austenitic at all temperatures, and the thermodynamics of dilute solutions of carbon in y iron only are considered. 

Sulfuric acid tetrahydrate (SAT) also ultimately freezes out of these ternary solutions (Molina et al., 1993 Iraci et al., 1995). At higher temperatures found at higher altitudes in the middle and low latitudes, sulfuric acid monohydrate (SAM) may also be stable (Zhang et al., 1995). 

Some field measurements of HN03 suggest that the formation of liquid or solid Type I PSCs depends on the initial background sulfate aerosols on which the PSCs form. If they are liquid, then liquid ternary solution PSCs tend to form first as the temperature drops below 192 K, whereas if the sulfate particles are initially solids, solid Type lc PSCs may be generated (Santee et al., 1998). 

Figure 12.22 shows the composition in terms of the weight percent HNO, and H2S04 as a function of temperature as solid SAT is cooled from 194 K under conditions corresponding to a pressure of 50 rnbar in an atmosphere containing 5 ppm HzO and an HNO, concentration of 10 ppb (Koop and Carslaw, 1996). Under these particular conditions, as the temperature falls below 192 K, the SAT is in equilibrium with a liquid film on the particle containing both HN03 and H20. The particular temperature at which SAT deliquesces is a function of the water vapor and gaseous nitric acid concentrations as shown in Fig. 12.23. As the temperature falls further and more HNO, and HzO are taken up into the liquid, the solid SAT dissolves completely, forming a ternary solution of the two acids and water. This solution can then act again to nucleate PSCs.

CIO and decrease in HCI as the temperature fell, even though PSCs were not present (although it is possible that they were present at some earlier time). These observations were shown to be consistent with heterogeneous reactions on liquid binary and ternary solutions, with the temperature dependence reflecting the increased reaction probability for HCI + C10N02 due to increased solubility of HCI at the lower temperatures. 

The kinetics of these reactions in liquid solutions characteristic of the stratosphere, such as concentrated H2S04-H20 or ternary solutions with HN03, depend on temperature as expected and in some cases at least, on acidity as well. For example, Donaldson et al. (1997) have shown that the second-order rate constant for the... 

Beyerle, G., B. Luo, R. Neuber, T. Peter, and I. S. McDermid, Temperature Dependence of Ternary Solution Particle Volumes As Observed by Lidar in the Arctic Stratosphere during Winter 1992/1993, J. Geophys. Res., 102, 3603-3609 (1997). 

Knowledge of the expressions for the chemical potentials of each of the components allows theoretical prediction of the critical concentration boundaries of the phase diagram for ternary solutions of biopolymeri + biopolymer2 + solvent. According to Prigogine and Defay (1954), a sufficient condition for material stability of this multicomponent system in relation to phase separation at constant temperature and pressure is the following set of inequalities for all the components of the system ... 

These sulfuric acid particles become less concentrated as the temperature decreases or the water vapour increases. Under very cold stratospheric conditions, these liquid aerosols may take up water and HNO, forming ternary solutions H,S0/HN0,/H,0, which eventually freeze [19,24,26], Below 192 K, HNO, becomes the dominant condensed acid, and H,S04 drops to below 3 wt %. The thermodynamics and freezing nucleation of ice and H,S04 or HNO, hydrates from such solutions are however not well understood [27,28]. Other types of solid particles, such as the less stable nitric acid dihydrate (NAD, HN0,.2H,0) [29], sulfriric acid tetrahydrate (SAT, H S04.4H,0) [18,30], sulphuric acid hemihexahydrate (SAH, H2S04.6.5H20) [18], nitric acid penta-hydrate (NAP, HN03.5H,0) [31] and more complex sulfuric acid/nitric acid mixed hydrates [32] may also be a key to understanding Type IPSC nucleation and evolution [28],... 

Qualitatively, the same effect has been observed in ternary solutions of p- PODZ, PA-6 and sulfuric acid [104]. At room temperature the quiescent system displays phase separation above 14% of total polymer concentration. Above the critical concentration shearing of initially biphasic solutions led to transparent one-phase systems. After cessation of the shear stress the biphasic morphologies recovered. 

The reason for the dehydration and denitrification of the Antarctic stratosphere is the formation of the PSCs, whose chemistry perturbs the composition in the Antarctic stratosphere. Polar stratospheric clouds can be composed of small (< 1 pm diameter) particles rich in HNO3 or at lower temperatures (<190 K) larger (10 pm) mainly ice particles. These are often split into two categories, the so-called Type 1PSC, which contains the nitric acid either in the form of liquid ternary solutions with water and sulfuric acid or as solid hydrates of nitric acid, or Type II PSCs made of ice particles. The ice crystals on these clouds provide a surface for reactions such as... 

In summary, IGC is an experimentally attractive method for obtaining polymer-polymer interaction parameters in polymer blends at temperatures above Tm for a crystalline blend, and above Tg for an amorphous blend. This technique yields interaction parameters that are generally consistent with data obtained with other techniques such as vapor sorption, melting point depression, neutron scattering, and small-angle X-ray scattering (40). Advances in IGC of polymer blends will require increased experimental precision in order to improve the consistency of the data, as well as refinements of thermodynamic models to allow better interpretation of interactions in ternary solutions. 

Beyer, K.D., B. Luo, R. Neuber, and T. Peter, Temperature dependence of ternary solution particle volumes as observed by lidar in the Arctic stratosphere during winter 1992/1993. J Geophys Res 102, 3603, 1997. 

Let us first consider how reactive the different surfaces are, and where they are to be found in the stratosphere. Laboratory studies have shown that water ice, NAT, and liquid ternary solutions are all effective for activating chlorine heterogeneously, but with differing efficiencies and with different dependencies on temperature, water vapor abundance, and pressure (e.g., Carslaw et al., 1997a JPL, 1997, and references therein). These dependencies are related to the thermodynamics of the different surfaces, which not only control their surface areas, but also their composition (especially the uptake of HC1 onto/into the particles). 

This curve will, of course, lie in the plane formed by one face of the prism. In a similar manner we obtain the freezing-point curves Ak C and B gC. These curves give the composition of the binary liquid phases in equilibrium with one of the pure components, or, at the eutectic points, with a mixture of two solid components. If to the system represented say by the point ki, a small quantity of the third component, C, is added, the temperature at which the two solid phases A and B can exist in equilibrium with the liquid phase is lowered and this depression of the eutectic point is all the greater the larger the addition of C. In this way we obtain the curve which slopes inwards and downwards, and indicates the varying composition of the ternary liquid phase with which a mixture of solid A and B are in equilibrium. Similarly, the curves fegK and k K are the corresponding eutectic curves for A and C, and B and C in equilibrkim with ternary solutions. At the point K, the three solid components... 

Instead of employing the prism, the change in the composition of the ternary solutions can also be indicated by means of the projections of the curves A2K, and on the base of the prism, the particular temperature being written beside the different eutectic points and curves. This is shown in Fig. 103. 

From the projection of the curves for ternary solutions on the base of the prism, as shown in Fig, 103, one obtains exact information regarding the composition of the different solutions. But the temperature varies from point to point of the curves, and the temperature slope of the curves is not shown in this diagram. The diagram can be improved and made to give fuller information by joining the points of equal temperature, and so producing a series of temperature contour lines (see Fig. ill, p. 226). 

On the other hand, by sacrificing some of the information regarding the composition of the ternary solutions, it is possible to secure a plane diagram which will give the temperature variations of the system. Thus, by projecting perspectively the curves in Fig. 102 and Fig. 104 not on the base of the prism but on one of the faces, say the face BC, of the prism, a poly thermal diagram is obtained which shows the relative proportions of the two components B and C in the different systems. The proportion of the component A in the different systems,... 

Ternary Systems.—Wq pass over the binary system FeClg—HgO, which has already been discussed (p. 187), and the similar system HCl—HgO (see Fig. 132), and turn to the discussion of some of the ternary systems represented by points on the surface of the model between the planes XOT and YOT. As in the case of carnallite, a plane represents the conditions of concentration of solution and temperature under which a ternary solution can be in equilibrium with a single solid phase (bivariant systems), a line represents the conditions for the co-existence of a solution with two solid phases (univariant systems), and a point the conditions for equilibrium with three solid phases (invariant systems). 

Figure 8. Concentration dependence of components of a ternary solution on temperature (top plot) anthracene, (center plot) 2-methylanthra-cene, (bottom plot) benzanthracene.

Ross Foam Foam produced from a binary or ternary solution under conditions in which its temperature and composition approach (but do not reach) the point of phase separation into separate immiscible liquid phases. 

Eutectic formation, as predicted by the phase rule, can have a dramatic effect on pH buffer solutions during freezing. In a ternary solution of two salts and water, four eutectic points may, in principle, be identified, of which one is a ternary eutectic (at the lowest temperature), while the other three are binary eutectics of the three pairs of components. Some eutectic data for sodium and potassium phosphate buffer salts with ice are summarised in Table For mixtures of the sodium salts, the... 

The hardness of CoAl is higher than that of NiAl with a minimum for the stoichiometric composition at temperatures below 800°C (Westbrook, 1956), i.e. deviations from stoichiometry produce constitutional defects with restricted mobility at lower temperatures which strengthen the CoAl, as in the case of NiAl. The characteristics of slip correspond to those of NiAl (Baker and Munroe, 1990). The hardening of CoAl by constitutional defects and ternary solutes, i.e. Mn, Re, and Ti, has been studied in detail (Fleischer, 1993 c, d, e). 

Polar stratospheric clouds have been classified into two broad types, so-called Type I and Type II (Table 4.1). Type I PSCs have been further subdivided into Type la and Type Ib. Type la PSCs have traditionally been identified as crystals of nitric acid trihydrate, HNO, 3 H2O, denoted NAT, that form once temperatures fall below about 195 K. Type lb PSCs consist of supercooled ternary solutions of HNO3/H2SO4/H2O, also forming at about the same temperature threshold. Type II PSCs are largely frozen water ice, nonspherical crystalline particles, that form at temperatures below the ice frost point. The ice frost point, for example, at 3 X 10 Torr H O is 191 K. Despite the above classification, the composition of PSCs is still uncertain (Toon and Tolbert, 1995). 

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