High upper critical

There are several dozen metallic AB2 compounds called Laves phases that are superconducting they have either cubic or hexagonal crystal structures. Some have critical temperatures above 10 K and high upper critical magnetic fields Bc2- For example, Zri/2Hfi/2V2 has rc = 10.1K, B 2 = 24 T, and a compound with a different Zr/Hf ratio has similar and Bc2 values with the critical current density Jc 4 X 10 A/cm. These materials also have the advantage of not being as hard and brittle as some other intermetallics and alloys with comparable transition temperatures. 

The S-L-V curve intersects the gas-liquid critical curve in two points the lower critical end point (LCEP) and the upper critical end point (UCEP). At these two points, the liquid and gas phases merge into a single fluid-phase in the presence of excess solid. At temperatures between Tlcep and Tucep a S-V equilibrium is observed. The solubility of the heavy component in the gas phase increases very rapidly with pressure near the LCEP and the UCEP. Near the LCEP the solubility of heavy component in the light one is limited by the low temperatures. In contrast, near the UCEP the solubility of heavy component in the light one is high, owing to the much higher temperatures [6],... 

The high critical temperature superconductors show a strong anisotropy in different properties critical current density [1], resistivity [2, 3] and the upper critical field [2],... 

Figure 3.15 Polypropylene structures, (a) Type I open cell structure formed at low cooling rates, (b) Type II fine structure formed at high cooling rates [37]. Reprinted with permission from W.C. Hiatt, G.H. Vitzthum, K.B. Wagener, K. Gerlach and C. Josefiak, Microporous Membranes via Upper Critical Temperature Phase Separation, in Materials Science of Synthetic Membranes, D.R. Lloyd (ed.), ACS Symposium Series Number 269, Washington, DC. Copyright 1985, American Chemical Society and American Pharmaceutical Association...

The high pressure termination of the S-L-G line gives the pressure-temperature location of the upper critical end point. The value for the UCEP temperature shown by the high pressure portion of our S-L-G line is 60.1°C. This agrees with the value for the UCEP temperature reported by McHugh and Yogan (h9). 

From absolute zero (0°K) to 25°C, most hydrophilic solute remains separated in water to an upper critical solution or upper consolute temperature (Tc) (Glasstone and Lewis, 1963) whereupon they merge. In the opposite direction (from high to low temperature), solute and solvent or two solute phases in a common solvent may remain separated to a lower Tc, where they again merge. Many cellulose derivatives have a lower Tc in the vicinity of 45°C. The lower and upper Tc are called cloud points because of the incipient cloudiness observed there. This incipient cloudiness in a formerly translucent dispersion is evidence that the solute has emerged from a secondary minimum on its way to a gel (Walstra et al., 1991). 

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