Ionic phase diagram

If curvature so prescribed is the major determinant of self-assembly, then phase diagrams ought to exhibit uiuversality, yet ionic and non-ionic phase diagrams are different (Fig. 3.4). 

The Kraft point (T ) is the temperature at which the erne of a surfactant equals the solubility. This is an important point in a temperature-solubility phase diagram. Below the surfactant cannot fonn micelles. Above the solubility increases with increasing temperature due to micelle fonnation. has been shown to follow linear empirical relationships for ionic and nonionic surfactants. One found [25] to apply for various ionic surfactants is ... 

Charged particles in polar solvents have soft-repulsive interactions (see section C2.6.4). Just as hard spheres, such particles also undergo an ordering transition. Important differences, however, are that tire transition takes place at (much) lower particle volume fractions, and at low ionic strengtli (low k) tire solid phase may be body centred cubic (bee), ratlier tlian tire more compact fee stmcture (see [69, 73, 84]). For tire interactions, a Yukawa potential (equation (C2.6.11)1 is often used. The phase diagram for the Yukawa potential was calculated using computer simulations by Robbins et al [851. 

There are three possibilities of letting the neutral species appear in the ionic partition diagram. Indeed, as the partition coefficient of the neutral species is neither potential- nor pH-dependent, the variable can be either the neutral species in the aqueous phase or that in the organic phase. However, to account for the experimental reality, it is more convenient to introduce the total mole number of neutral species [297], defined as ... 

The system can exist in a variety of phases depending on the parameters. Figure 11a shows the phase diagram in the ionic strength-pH plane. The pH... 

Although chemically similar, the inorganic and organic chloroaluminate molten salts or ionic liquids, as some prefer to call them, differ greatly with respect to their melting temperatures and physical properties. Figures 1 and 2 show the phase diagrams... 

Figure 4.2 The Lu203-TiC>2 phase diagram. [Adapted from A. V. Shlyakhtina et al., Solid State Ionics, 177, 1149-1155 (2006).]...

Melting point J.D. Holbrey, R.D. Rogers, Melting Points and Phase Diagram, in P. Wasserscheid, T. Welton (Eds.), Ionic Liquids in Synthesis, Wiley VCH, Weinheim 2003, p. 41. 

Peck DH, Miller M, and Hilpert K. Phase diagram study in the Ca0-Cr203-La203 system in air and under low oxygen partial pressure. Solid State Ionics 1999 123,47-57. 

Thus for undiluted polymers the relaxation behaviour can be examined over a wider range of apparent frequencies. Similar functions can be constructed for other regions of the phase diagram and other rheological experiments. The method of reduced variables has not been widely tested for aqueous crosslinked polymers. Typically these are polyelectrolytes crosslinked by ionic species. Some of these give rise to very simple relaxation behaviour. For example 98% hydrolysed poly(vinyl acetate) can be crosslinked by sodium tetraborate. The crosslink that forms is shown in Figure 5.31. 

Figure 5.2. The phase diagram of the Sr-H system. An intermediate phase, stable in a range of temperature and composition values (solid solution [) is formed in the Sr-rich region. The other phase (practically a stoichiometric compound) corresponding to the formula SrH2 may be considered a representative of the ionic hydrides. The low-temperature form of this compound has the oP12-Co2Si-type structure.

Figure 5.5 Phase diagram for the ionic liquids [C mimllPFe]. Open squares are glass transitions, closed squares are melting points, and circles are clearing transitions LC is a liquid crystalline phase.

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