Mutual dissolution

Solution Deposition of Thin Films. Chemical methods of preparation may also be used for the fabrication of ceramic thin films (qv). MetaHo-organic precursors, notably metal alkoxides (see Alkoxides, metal) and metal carboxylates, are most frequently used for film preparation by sol-gel or metallo-organic decomposition (MOD) solution deposition processes (see Sol-GEL technology). These methods involve dissolution of the precursors in a mutual solvent control of solution characteristics such as viscosity and concentration, film deposition by spin-casting or dip-coating, and heat treatment to remove volatile organic species and induce crystaHhation of the as-deposited amorphous film into the desired stmcture. 

Pits seldom form in close proximity to one another and it would appear that the area of passivated metal, which acts as the cathode for the local cell, is protected by the anodic dissolution of metal within the pit—a phenomenon that is referred to as the mutually protective effect see Section 1.5). 

Choices of precursor(s) may be dictated by solubility, reactivity, or other property. For multicomponent systems, mutual solubility is another factor that must be considered. For such solutions, the solvent selected must facilitate dissolution of all precursors. 

In particular, the rotation and swinging of the extracellular domains coupled with rotation and tilting of the transmembrane domain might occur during dissolution of the receptor homodimers (as is very schematically illustrated by Fig. 5) and formation of heterodimers and can be important at the initial and final stages of interaction of the TGF-P dimer with both receptor dimers. Such motions and conformational transitions of the extracellular and transmembrane domains cannot occur without similar motions of the intracellular domains, resulting in changes of their mutual orientation, the points of contact between them, and hence of the distance between the... 

The interfacial behavior of the copolymer/PMMA two-layer wet etch PCM system is similar to the AZ/PMMA system because of an identical bottom layer and a similar solvent for the top layer. In this case, consideration of the interfacial layer leads one to avoid using completely mutually exclusive developers. The developer for the bottom planarizing layer should be chosen such that it also develops the top layer at an low dissolution rate so that the interfacial layer can be broken through during the second... 

The necessary condition for dissolution of a substance is that energetic stabilization is obtained by dissolution. The energetic stabilization depends on the energies of three interactions, i.e., solute-solvent, solute-solute, and solvent-solvent interactions. When the solvent and the solute are both nonpolar, all three interactions are weak. In that case, the energy gained by the entropy of mixing of the solvent and the solute plays an important role in the high mutual solubility. For the dissolution of electrolytes, see Section 2.1. 

Iron-nickel alloys are known to dissolve in the aluminium melts non-selectively. " As seen from Table 5.3, during dissolution of a 50 mass % Fe-50 mass % Ni alloy the ratio, cFe cNi, of iron to nickel concentrations in the melt is 1.00 0.05, i.e. it is equal to that in the initial solid material. The same applies to other alloys over the whole range of compositions. Respective saturation concentrations are presented in Table 5.4. The data obtained display a strong mutual influence of the elements on their solubilities in liquid aluminium because in its absence the solubility diagram for a constant temperature would be like that shown by the dotted lines in Fig. 5.5, with the eutonic point, E, at 2.5 mass % Fe and 10.0 mass % Ni. The effect of iron on the nickel solubility is seen to be more pronounced than that of nickel on the iron solubility. 

Dissolution-precipitation reactions often exhibit characteristic time scales that are much larger than those for complexation reactions in aqueous solution. When this is true, the aqueous species in a soil solution will come to mutual equilibrium long before they equilibrate with the solid phase via the reaction in l-q. 3.1. It is possible under these circumstances to define two useful criteria for dissolution precipiialionequilibrium, the ion activity product (IAP) ... 

The cause of concentration polarization is the slow rate of diffusion of ions which cannot counterbalance the concentration variations in the close proximity of both electrodes arising from the discharge or formation of ions. Let us imagine, e. g. the electrolysis of a silver nitrate solution between two silver electrodes. When no current is flowing through the system the potentials at both electrodes are of the same value and are mutually compensated. As soon as electrolysis starts, the concentration of Ag+ ions will begin to rise owing to the dissolution of silver at the anode on the contrary the concentration of these ions round the cathode will fall because the deposition of metallic silver will here take place. The concentration differences produced will never be fully compensated... 

We can conclude that two substances with equal solubility parameters should be mutually soluble due to the negative entropy factor. This is in accordance with the general rule that chemical and structural similarity favours solubility. As the difference between 81 and S2 increases, the tendency towards dissolution decreases. 

In liquid/solid systems with a high mutual solubility (as for many metallic systems), calculations show that the size of the deformed area close to the triple line can attain dimensions of about a micron in a minute or so. However, in this case, the equilibrium configuration at the triple line can be masked by the dissolution of the solid in the liquid (Warren et al. 1998) as discussed in Section 2.2.1. 

D Me-S surface alloy and/or 3D Me-S bulk alloy formation and dissolution (eq. (3.83)) is considered as either a heterogeneous chemical reaction (site exchange) or a mass transport process (solid state mutual diffusion of Me and S). In site exchange models, the usual rate equations for the kinetics of heterogeneous reactions of first order (with respect to the species Me in Meads and Me t-S>>) are applied. In solid state diffusion models, Pick s second law and defined boundary conditions must be solved using Laplace transformation. 

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