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Inverse temperature transitions evolution

E.7 Evolution by Inverse Temperature Transition Reverses The Otherwise Universal Arrow of Time 569... [Pg.569]

E.7.2 Evolution by Inverse Temperature Transition Achieves Biology s Reversal of the Universal Arrow of Time... [Pg.569]

Biology s reversal of the much-noted arrow of time and equivalently biological evolution derive simply from fundamental reality of biosynthesis within the context of inverse temperature transitions as expressed in the hydrophobic consilient mechanism. The production of a new and improved protein-based machine occurs by chance, but most significantly it occurs at a cost in energy no greater than that required to produce the initial less useful protein-based machine. This is the nature of the biosynthesis of protein and of the other great macromolecules (the nucleic acids, DNA and RNA) of biology. [Pg.569]

Thus, from the perspective of the inverse temperature transition, evolution and natural selection become apparent consequences for protein-based machines that function by the hydrophobic and elastic consilient mechanisms. [Pg.571]

Several references were made above to the term phase inversion temperature. With the exceptions of Eqs. (9.17) and (9.18), however, no specific reference was made to the effect of temperature on the HLB of a surfactant. From the discussions in Chapter 4, it is clear that temperature can play a role in determining the surface activity of a surfactant, especially nonionic amphiphiles in which hydration is the principal mechanism of solubilization. The importance of temperature effects on surfactant solution properties, especially the solubility or cloud point of nonionic surfactants, led to the evolution of the concept of using that property as a tool for predicting the activity of such materials in emulsions. Since the cloud point is defined as the temperature, or temperature range, at which a given amphiphile loses sufficient solubility in water to produce a normal surfactant solution, it was assumed that such a temperature-driven transition would also be reflected in the role of the surfactant in emulsion formation and stabilization. [Pg.311]

J.L. Salager Evolution of Emulsion Properties Along a Transitional Inversion Produced by a Temperature Variation. In Proceedings of the 3rd Word Congress on Emulsions l-F-094, Lyon, France (2001). [Pg.48]

Raman spectra as a function of temperature are shown in Fig. 21.6b for the C2B4S2 SL. Other superlattices exhibit similar temperature evolution of Raman spectra. These data were used to determine Tc using the same approach as described in the previous section, based on the fact that cubic centrosymmetric perovskite-type crystals have no first-order Raman active modes in the paraelectric phase. The temperature evolution of Raman spectra has indicated that all SLs remain in the tetragonal ferroelectric phase with out-of-plane polarization in the entire temperature range below T. The Tc determination is illustrated in Fig. 21.7 for three of the SLs studied SIBICI, S2B4C2, and S1B3C1. Again, the normalized intensities of the TO2 and TO4 phonon peaks (marked by arrows in Fig. 21.6b) were used. In the three-component SLs studied, a structural asymmetry is introduced by the presence of the three different layers, BaTiOs, SrTiOs, and CaTiOs, in each period. Therefore, the phonon peaks should not disappear from the spectra completely upon transition to the paraelectric phase at T. Raman intensity should rather drop to some small but non-zero value. However, this inversion symmetry breakdown appears to have a small effect in terms of atomic displacement patterns associated with phonons, and this residual above-Tc Raman intensity appears too small to be detected. Therefore, the observed temperature evolution of Raman intensities shows a behavior similar to that of symmetric two-component superlattices. [Pg.608]


See other pages where Inverse temperature transitions evolution is mentioned: [Pg.78]    [Pg.82]    [Pg.86]    [Pg.570]    [Pg.475]    [Pg.475]    [Pg.175]    [Pg.78]    [Pg.208]    [Pg.160]    [Pg.143]    [Pg.357]    [Pg.20]    [Pg.35]    [Pg.745]    [Pg.31]   
See also in sourсe #XX -- [ Pg.569 , Pg.570 ]




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