Temperature-induced structural transitions

Reiersen H, Clarke AR, Rees AR (1998) Short elastin-like peptides exhibit the same temperature-induced structural transitions as elastin polymers implications for protein engineering. J Mol Biol 283 255-264... 

Another important class of studies is to investigate temperature-induced structural transitions. This has been performed for the metal Be. At ambient pressure. Be transforms from a low temperature hexagonal close-packed (hep) structure to a high temperature body-centered cubic (bcc) structure at approximately 1530 K before it melts at about 1560 This transition is interesting in several... 

Pressure-temperature-induced structural transitions for rare earth tri-aluminides, determined on quenched samples by Cannon and Hall... 

As in the case of electric field induced structural transition, the temperature induced structural transition is also associated with critical slowing down of the director fluctuations. However, as reorientation of the droplet director can occur along any direction in the xy plane, both 6n ey and 6n ex fundamental modes exhibit a critical behaviour of 1/ro in the vicinity of Tc and consequently a slowing down detected in the dynamic light scattering experiments is more pronounced than in case of electric field induced transition. 

Examples of biochemical processes successfully studied by spectroscopic monitoring and multivariate resolution techniques include protonation and complexation of nucleic acids and other events linked to these biomolecules, such as drug intercalation processes and salt, solvent, or temperature-induced conformational transitions [90-97], In general, any change (thermodynamic or structural) that these biomolecules undergo is manifested through a distinct variation in an instrumental signal (usually spectroscopic) and can be potentially analyzed by multivariate resolution techniques. 

On the other hand, hysteresis of the temperature-induced structural phase transitions in nanostructures with first-order phase transitions reduce useful magnetocaloric effect to transform cycling between martensite (M) and austenite (A) phases under application. In addition, the size, surface and boundary effects on thermal hysteresis loops have been under consideration for the development of research on nanostructured materials. Experimental data indicate that nanostructured materials offer many interesting prospects for the magnetization data and for understanding of temperature-induced martensite/austenite phase transitions. 

The reliability of these two-dimensional connectivity experiments is now well enough established that they can be used with confidence in the investigation of unknown structures in conjunction with diffraction studies. In a first step in this direction, a study of the three-dimensional bonding connectivities in ZSM-11 in both its high- and low-temperature forms has been reported [86]. As described earlier these are related to each other by a temperature-induced phase transition. The high-temperature form is known to have tetragonal symmetry with space... 

The effect of s—d hybridization on the relative stability of the structures of metallic Ca and Sr has been studied as a function of temperature and pressure within the context of the pseudopotential theory for metals. The inclusion of hybridization is found to favour the f.c.c. structure at all pressures and, in particular, is necessary to explain the observed f.c.c. structure in these metals at zero temperature and pressure. Phase boundaries are calculated by equating the free energy of the f.c.c. structure to that of the b.c.c. structure. Temperature-induced phase transitions are predicted to occur at 555 K in Ca and 625 K in Sr as compared with the actual temperatures of 721 and 830 K. From the changes in free energy of the reactions of the alkaline-earth metals with gases as a function of temperature, it is confirmed that at 298— 1400 K almost all of the residual gases in electrovacuum devices combine with the metals to form stable compounds. The dehydration of calcium... 

Temperature-induced phase transition from orthorhombic to trigonal structure has been detected in Ndi Sm AlOa samples with x = 0.4 and 0.6 at 463 and 643 K, respectively (Yoshikawa et al., 1998). It was shown that the transition is... 

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