Amorphous solid phase

Considerably complicated realizes ablation of water from Zn Co j P O -H O. Heating of it to 603 K is accompanied with practically full destaiction of diphosphate stmcture. In composition of X-ray amorphous solid phase take place the processes of anion condensation. On their realization indicates formation of triphosphate with lineai anion stmcture (5,6 mas.% in count on P,0 ) in composition of burning products. 

Most recently, kinetic data from the melt have been applied to the amorphous solid phase. This is based on the well-accepted assumptions that the chemistry in the melt is the same as in the latter phase and that all of the end group reactions take place in the latter phase [11, 21, 35], The activation energy AE, and the frequency factor A, defined in the following equation ... 

Large concentrations of Fe + develop in the soil solution in the weeks following flooding, often several mM or tens of mM (Figure 4.5). Calculations with chemical equilibrium models show that the ion activity products of pure ferrous hydroxides, carbonates and other minerals are often exceeded 100-fold (Neue and Bloom, 1989). Evidently precipitation of these minerals is inhibited, probably as a result of adsorption of foreign solutes, such as dissolved organic matter and phosphate ions, onto nucleation sites (Section 3.7). However, once a sufficient supersaturation has been reached there is a rapid precipitation of amorphous solid phases, which may later re-order to more crystalline forms. Only a small part of the Fe(II) formed in reduction remains in solution the bulk is sorbed in exchangeable forms or, eventually, precipitated. 

Despite the tremendous progress made in this field, there is still a severe drawback. The quantum chemistry developed by theoretical chemists tools are primarily suited for isolated molecules in vacuum or in a dilute gas, where intermolecular interactions are negligible. Another class of quantum codes that has been developed mainly by solid-state physicists is suitable for crystalline systems, taking advantage of the periodic boundary conditions. However, most industrially relevant chemical processes, and almost all of biochemistry do not happen in the gas phase or in crystals, but mainly in a liquid phase or sometimes in an amorphous solid phase, where the quantum chemical methods are not suitable. On the one hand, the weak intermolecular forces,... 

The solid phase is considered to be an amorphous pile having a maximum disorder amongst the particles. Such a close-packed assemblage has some similarity with a liquid. But an essential difference from liquids lies in the absence of the supplementary free volume. An amorphous solid phase with interacting particles having a certain degree of mobility is considered to be essential for the diffusion process in plastic materials. 

Kawai, T., Fukuda, N., Groschl, D., Kobatake, S., and Irie, M. Refractive index change of dithienylethene in bulk amorphous solid phase. Jpn. J. Appl. Phys. 38, 1194, 1999. 

The Ostwald step rule, or the mle of stages, postulates that the precipitate with the highest solubility (i.e., the least stable solid phase) will form first in a consecutive precipitation reaction. This mle is very well documented mineral formation via precursors and intermediates can be explained by the kinetics of the nucleation process. The precipitation sequence results because the nucleation of a more soluble phase is kinetically favored over that of a less soluble phase because the more soluble phase has the lower solid-solution interfacial tension (7cw) than the less soluble phase (equation 50). In other words, a supersaturated solution will nucleate first the least stable phase (often an amorphous solid phase) because its nucleation rate is larger than that of the more stable phase (Figure 13.26). While the Ostwald step mle can be explained on the basis of nucleation kinetics, there is no thermodynamic contradiction in the initial formation of a finely divided precursor. 

The state of the template tetrapropylanunonium ion [TPA] was also monitored with Raman spectroscopy during various stages of ZSM-5 synthesis. It was found that this cation is trapped into the amorphous solid phase at the earliest stages of the synthesis in the all-trans configuration. Upon crystallization of the zeolite, there is a forced change in the conformation of the trapped tetrapropylammonium cation such that it can fit into the zig-zag zeolite channels. The template [TPA]" was decomposed by... 

Since solubility is the concentration of protein in solution at equilibrium with the solid phase, the state of protein in the solid phase affects the solubility in the solution phase. Theoretical treatment of the protein solubility problem has often ignored solid phase interactions of the protein due to its complexity. A crystalline solid phase is expected to render a lower solubility than the amorphous solid phase. However the complexity and the heterogeneity of the protein in the solid state (e.g. amorphous, gel, or crystalline, or precipitates of native or denatured forms) makes it difficult to directly assess solid state effects. 

There is not much difference in T for the two doublets A and B, so ferric ion in both environments belongs to the same phase. Results on ferrous iron indicated that the ions are fully hydrated when the water content of the membrane exceeds 6 wt %, and partially hydrated at lower values. We conclude that the ions are entirely located in an aqueous phase in the Nafion membranes, and they are not directly incorporated in the crystalline or amorphous solid phases of the polymer. This is quite consistent with small angle scattering results (26). 

Segment motion occurs both in dilute solution and in the solid amorphous phase, provided the polymer is above its glass transition, Tg. This characteristic temperature of all amorphous polymers will be considered later. It can be defined for our purposes as the temperature below which this type of coordinated segment motion can no longer occur. An important kinetic difference between a polymer molecule in solution and the same molecule in an amorphous solid phase is that in dilute solution there can be a net translational motion of the center of mass of the polymer as in Fig. 2a, whereas in the solid the rate of this process is exceedingly slow. 

The size and shape of the particles is affected mainly by the concentration of precursors, pH, radiation dose (or irradiation time), and the presence of surfactant. Oxide compounds may be prepared either directly via irradiation at room temperature (RT) or indirectly via subsequent heat treatment of formed amorphous solid phase. 

Aside from simple metal oxides, more intricate oxide compounds may also be prepared by the radiation method, as was illustrated by powder yttrium aluminum garnet (YAG, Y3AI5O12) synthesis (Cuba and Niki 2011, Cuba et al. 2011). YAG powders were prepared from aqueous solutions containing potassium formate, yttrium nitrate, and aluminum chloride or nitrate via irradiation by accelerated electrons or UV light and consequent calcination of formed amorphous solid phase. 

Abstract A surface state equation that is independent of the physical state of the phases is introduced. This relationship exists between individual variables and holds for any phase. Using this equation, quantities that are either inaccessible to measurement or not easily available can be calculated. It can therefore also be applied to the interface of amorphous solid phases or crystal lattices of different Miller indices. 

Nevertheless, some exceptions exist and not all additives which are good stabilizers show chemical and bonding properties similar to water. Many experimental data have shown that the stabilization of fragile and thermosensible pharmaceutical proteins requires a lyoprotectant that is a good glass-former, leading to a single amorphous solid phase, with a moderate interaction with the protein surface to avoid phase separation (crystallization, etc.). 

A substance normally exists in one of three states crystalline, liquid, or gaseous (see Figs. 5 and 6). It does not usually pass through an amorphous solid phase in this sense, it is an anomaly. The case that we are concered with is what we commonly call GLASS. 

The precise conditions of hydrolysis (viz., the compositions of the solutions that are combined, the rate of combination, the amount of agitation, and the temperature) determine the nature and quantity of transient polymeric species, colloidal particles, or amorphous solid phases formed. 

Metallic Crystals Amorphous Solids Phase Changes... 

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