Near-melt behavior

In the present article, we review recent progress in this subject area. In Sec. 2, we give a short overview on the chemical composition of the low melting salts and ILs. In Sec. 3 we address the problem of the electrolyte solution structure at conditions of low reduced temperature, where phase separations are known to occur. In Sec. 4, we consider experimental and theoretical results concerning the location of the two-phase regime in solutions of ionic fluids. In Sec. 5 we finally review theoretical and experimental results on near-critical behavior of ionic fluids. 

It has been argued (62) that the golden color of Cs is no intrinsic property of the element, but is caused by oxygen contamination and formation of dark-colored suboxides. Yet it has been shown (11) that the trace of oxygen in a sample CsOo.00001 can be detected by the characteristic melting behavior, whereas a measurable change in color does not occur before a composition near CsOo.oi is reached. 

Hastie, G.P. et al., Examination of the structure and melting behavior of thin film n-aUcanes using ultrasoft polarized near-edge x-ray absorption spectroscopy, J. Chem. Soc.-Faraday Trans. 92, 783-789, 1996. 

Aydin et al. reported the influence of alkali treatment on the mechanical, thermal, and morphological properties of eco-composites made by short flax fiber reinforced PLA Scanning electron microscopy (SEM) revealed that the packed structure of the fibrils was deformed by the removal non-cellulosic materials. The mechanical tests indicated that the modulus of the untreated flax fiber/PLA composites was higher than that of PLA on the other hand, the modulus of alkali treated flax/PLA was lower than that of PLA. Thermal properties of the PLA in the treated flax fiber reinforced composites were also affected. Tg values of treated flax fiber reinforced composites were lowered by nearly 10°C for 10% NaOH treatment and 15°C for 30% NaOH treatment. A bimodal melting behavior was observed for treated fiber composites different than both of neat PLA and untreated fiber composites [60]. 

Medium Freezing pressure atRT (kbar) Melting temperature at ambient pressure (K) Pressure range of nearly hydrostatic behavior (kbar) Reference... 

This effect was presumably caused by either defects arising from simultaneous growth of extended and folded lamellae or by the presence of thinner folded chain crystals in this region (e.g., surface free energy contributions). The high pressure material exhibit nearly equilibrium melting behavior and showed that almost perfect extendi chain crystals were present. 

Employing a dilatometric technique, Booth and coworkers determined the melt behavior of fractionated PPO as a function of crystallization temperature and by this technique found the thermodynamic melting point for PPO to be near 82° (Fig. 31), surprisingly 100° C lower than that of POM. These authors also detected three dilatometric transitions for partially isotactic material. The first below 60° was ascribed to the melting of lamellar crystals of limited thickness arising from the isotactic sequence. The other two transitions which depended on Tf- were attributed to the melting of lamellae with thicknesses determined by primary nudeation. 

Table 3.4 collects the differential scanning calorimetry (DSC) studies of iioii-isothermal crystallization and melting behavior of PP and its nanocomposites produced by the one-step technique. The data show that the melting point of PP is nearly not affected by the nano-silica. It means that no transition of... 

The thermal behavior (Figure 10.8) exhibited a clear result all branches longer than ethyl display nearly identical behavior. When increasing steric bulk, even the polymer decorated with an enormous adamantyl group is able to crystallize. Although there is a slight depression in peak melting temperature, the behavior of the bulky substitutes closely resembles that of... 

A continuous solid solution (Y, La)B6 with CaB -type of structure, Pm3m, was found from specimens b), but a restricted solid solution appears from alloys a), due to the different melting behavior of YBj (incongruent) and LaBg (congruent), which results in a nearly complete fractional crystallization of the two hexaborides. At variance with the results obtained by Bondarenko et al. (1966) on samples prepared by borothermal reduction, lattice parameters of specimens b) closely obey Vegard s rule and are shown in fig. 36 including superconductivity data. 

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