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Phase transitions localization under very high

The effects of such precipitation conditions as pressure, temperature, and solute and solvent concentrations are listed in Table 2. These effects are related to the behavior of the maximum attainable supersaturation 5 m, as described by Equation (51) and also to the phase transition at the mcp between the jet mixing and droplet dispersion mechanisms. As follows from our earlier discussions in Sections 2 and 5, the most uniform particles can be produced under conditions very close to the mcp (practically, just above P ), where the supercritical properties are most pronounced, local values of supersaturation are high, and the constants Cgq, Tn, and tq are the smallest. Figure 19a shows that particles produced below the mixture critical pressure are more agglomerated than to the individual and separate crystal particles obtained at high pressure. This is because the nuclei confined within the droplets at P < Pm coalesce and fuse during further growth. In this respect,... [Pg.145]

The nature of the 4f electrons in lanthanides and their compounds may be broadly characterized as being either localized or itinerant and is held responsible for a wide range of physical and chemical properties of both the elements and compounds. The localized states are marked by tightly bound shells or narrow bands of highly correlated electrons near the Fermi level and are observed at ambient conditions for all of the lanthanide elements. The pressure variable has a dramatic effect on the electronic structure of lanthanides, which in turn, drives a sequence of structural phase transitions under pressure. A very important manifestation of this change is the pressure-induced s to d electron transfer that is known to give rise to the... [Pg.275]

In addition, for solid samples or peptides in nonaqueous solvents, the amide II (primarily in-plane NH deformation mixed with C—N stretch, -1500-1530 cm-1) and the amide A (NH stretch, -3300 cm-1 but quite broad) bands are also useful added diagnostics of secondary structure 5,15-17 Due to their relatively broader profiles and complicated by their somewhat weaker intensities, the frequency shifts of these two bands with change in secondary structure are less dramatic than for the amide I yet for oriented samples their polarization properties remain useful 18 Additionally, the amide A and amide II bands are highly sensitive to deuteration effects. Thus, they can be diagnostic of the degree of exchange for a peptide and consequently act as a measure of protected or buried residues as compared to those fully exposed to solvent 9,19,20 Amide A measurements are not useful in aqueous solution due to overlap with very intense water transitions, but amide II measurements can usefully be measured under such conditions 5,19,20 The amide III (opposite-phase NH deformation plus C—N stretch combination) is very weak in the IR and is mixed with other local modes, but has nonetheless been the focus of a few protein-based studies 5,21-26 Finally, other amide modes (IV-VII) have been identified at lower frequencies, but have been the subject of relatively few studies in peptides 5-8,18,27,28 ... [Pg.715]


See other pages where Phase transitions localization under very high is mentioned: [Pg.173]    [Pg.434]    [Pg.3]    [Pg.174]    [Pg.149]    [Pg.149]    [Pg.257]    [Pg.367]    [Pg.412]    [Pg.438]    [Pg.56]    [Pg.231]    [Pg.44]    [Pg.477]    [Pg.873]    [Pg.46]    [Pg.111]   


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