Temperature-salinity diagram

Fig. 10-4 Average temperature/salinity diagrams for Pacific Oceans. (Reproduced with permission from G. L. Oceanography," pp. 138-139, Pergamon Press.)...

Fig. 2 a Temperature-salinity diagram of the Black Sea waters. Dashed lines water specific density (sigma-1) contours, b Climatic potential temperature-salinity curves in the Black Sea abyssal layer (deeper than 200 m). 1 Mean values, 2 and 3 standard deviations. Dashed lines water specific potential density (sigma-0) contours... 

Fig. 8 TS (temperature-salinity) diagram for the western basin waters. North and south refer to the northern and the southern parts of the western basin. October, 2003, Survey 2...

Fig. 9-5 Average temperature/salinity diagrams for the main water masses of the Atlantic, Indian, and Pacific Oceans. Reproduced from Pickard and Emery (1982) with the permission of Pergamon Press.

The sulfide vertical distribution correlates with vertical distributions of temperature, salinity, and density in the Black Sea. As a consequence, the H2S vertical distribution vs. salinity (Fig. 3a) and temperature (Fig. 3b) is consistent with the 9 -S curve (Fig. 3b). It is evidence that the thermohaline structure of the water column controls the vertical distribution of hydrogen sulfide in the basin [27]. Physical mixing processes dominate over the in situ sulfide production. Identifiable on the 0 -H2S and S-H2S diagrams, the boundaries of three water masses in the anoxic water column correspond strictly to the boundaries on the 0 -S diagram (Fig. 3b). The temperature-salinity relationship in the Black Sea is a result of large-scale external factors such as water and heat balance of the basin. 

Indeed, the eastern basin water intrusions into the western basin can often be clearly identified by means of TS (temperature-salinity) analysis. In many TS diagrams, the eastern basin water (EBW) can be seen as a distinct water type, whose mixing with the local western water type accounts for the observed spanning ranges of temperature and salinity. An illustrative example is shown in Fig. 8, corresponding to the fall of 2003. In this case, the complexity of the thermohaline structure in the western basin can be explained by the intermixing of three basic... 

Buzier, M. and Ravey, J.C. (1983) Solubilization properties of nonionic surfactants 1. Evolution of ternary phase diagrams with temperature, salinity, HLB, and ACN. /. Colloid Interface Sci., 91, 20-33. 

As already pointed out, the purpose of the phase scan is to determine the optimal temperature/ salinity that can produce microemulsion of desired type and properties. Once the optimal temperature/salinity is established, one can further investigate the effects of composition on phase behavior using the ternary phase diagram. 

FIGURE 16.7. Lower and upper critical tieUnes in a quaternary system at different temperatures and a plot of the critical end point salinities versus temperature, illustrating lower critical endline, upper critical endline, optimal line, and tricritical point for four-dimensional (4D) amphiphile-oil-water-electrolyte temperature phase diagram (39). 

Figure 7 Evolution of phase diagram of microemulsions shown schematically. The sequence of phase diagrams is obtained experimentally by varying temperature, salinity, oil chain length, or surfactant chemistry. Theoretically, many of these changes can be lumped into changes in the spontaneous curvature.

Because temperature (T) and salinity (S) are the main factors controlling density, oceanographers use T-S diagrams to describe the features of the different water masses. The average temperature and salinity of the world ocean and various parts of the ocean are given in Fig. 10-3 and Table 10-3. The North Atlantic contains the warmest and saltiest water of the major oceans. The Southern Ocean (the region around Antarctica) is the coldest and the North Pacific has the lowest average salinity. 

Figure 1.121. Probable ranges of oxygen activity and pH for the Te-type and Se-type deposits. The diagram was constructed mainly based on Barton et al. (1977) and Heald et al. (1987). Temperature = 250°C, ES = 0.02 molal, Salinity = 1 molal with Na/K (atomc ratio) = 9. Dotted area Te-type, Hatched area Se-type...

As noted earlier, the effect of salinity and temperature on the compressibility of seawater is slightly nonlinear. Even at a constant pressure, salinity and temperature interact in a nonlinear way to influence density. This is shown in Figure 3 5 for The curves in the diagram are lines of constant ct. As temperatures decline, the effect of increasing salinity on density increases. This is particularly pronounced at the low temperatures characteristic of the deep sea and surface polar waters. For seawater at 0°C, a rise in salinity from 35 to 36%o increases the a, density 15 times more than the effect of dropping the temperature by 1°C. 

T-S diagram The x-y graph of the temperature and salinity of water samples used to identify source water masses and types. 

Historically, however, it has been much more common for experimentalists to introduce a new variable into Figure 1, changing either the temperature of one or more samples of fixed composition, or the electrolyte concentration in a series of samples of fixed amphiphile—oil—water ratio. The former constitutes a temperature scan the latter experiment is widely known as a salinity scan. When the temperature of an amphiphile—oil—water system is varied, the phase diagram can be plotted as a triangular prism (because temperature is an intensive or field variable). When a fourth component (eg, NaCl) is added at constant temperature, tetrahedral coordinates, are appropriate (conjugate phases have different salinities, and the planes of different tietriangles are no longer parallel). 

FIGURE 6.11. Step-by-step schematic diagram of the rapid EnVision procedure. RT = room temperature TBS = Tris-buffered saline (pH 7.4) H = Meyer s hematoxylin. Reproduced, with permission, from Kammerer et al. (2001). Copyright 2001 Histochemical Society. 

T-S diagram a plot of temperature against salinity, with applications in defining water masses of different origin. 

Dispersion types in two-phase systems have been shown to correlate with the region of the phase diagram (i.e., the miscibility gap) in which the system lies (78-81). On the basis of these correlations and of the phase behavior reported in Chapter 4, it is expected that for many systems, increases of pressure, temperature, oil concentration, or salinity will cause dispersions of the C02-rich phase in the aqueous phase to invert. 

The phase behavior of microemulsions is complex and depends on a number of parameters, including the types and concentrations of surfactants, cosolvents, hydrocarbons, brine salinity, temperature, and to a much lesser degree, pressure. There is no universal equation of state even for a simple microemulsion. Therefore, phase behavior for a particular microemulsion system has to be measured experimentally. The phase behavior of microemulsions is typically presented using a ternary diagram and empirical correlations such as Hand s rule. 

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