Liquid silica

The unique field penetration into the liquid of a nonevanescent resonant mode like Tlij(7)0 is very promising for the sensing applications. To understand the origin of this behavior and further optimize the devices, a ray optical picture71 is presented. This type of resonant modes exist as if rays are bounced at the liquid/silica interface and confined in the liquid region as plotted in Fig. 8.32. From the viewpoint of ray optics, light is partially reflected (termed ray 1) and partially transmitted when it is... 

Molecular Structural Order and Anomalies in Liquid Silica. 

Strong Transition and Polyamorphism in the Energy Landscape of Liquid Silica. 

Fragile-to-Strong Crossover in Liquid Silica as Expressed by Its Potential-Energy Landscape. 

Silicone liquid, Unstated salt See SILICONE LIQUID Silica, etc. 

The Wettability of Ethyl- and Vinyltriethoxysilane Films Formed at Organic Liquid Silica Interfaces... 

The present paper describes the adsorption of ethyltriethoxysilane (ETES) and vinyltriethoxysilane (VTES) at various organic-liquid/silica interfaces. Films formed by these compounds on silica and glass from solution in nonpolar organic liquids were found to be oleophobic and so could be isolated by retraction that is, the substrate on which the films had been formed emerged dry from the solution, thus allowing direct examination of the adsorbed layer. 

It is reasonable therefore to consider that fused silica resembles liquid water. Just as liquid water retains from the parent shucture (ice) the three-dimensional network but not the long-range periodicity of the network, one would expect that liquid silica also retains the continuity of the tetrahedra, i.e., the space network, but loses much of the periodicity and long-range order that are the essence of the crystalline state. This model of fused silica, based on keeping the extension of the network but losing the translational symmetry of crystalline silica, implies a low concentration of charge... 

Comparison between Transport Processes in Simple Fused Salts and in Liquid Silica... 

There is a further analogy between the solvent actions exercised by water and a fused nonmetallic oxide. Just as water dissolves an electrolyte at the price of having its structure disturbed, so also the reaction resulting from the addition of a metallic oxide to a fused nonmetallic oxide like silica is equivalent to a bond mpture between the Si04 tetrahedra (Fig. 5.70). Solvent action occurs in fused oxide systems along with a certain breakdown of the network structures present in the pure liquid solvent (e.g., in pure liquid silica). 

Ionic Additions to the Liquid-Silica Network Glasses... 

Figure 4 shows a hydrophilic and the corre nding hydrophobic precipitated silica mixed with dimethylpolysiloxane. The mixture with the hydrophilic silica gives an almost solid compound. In contrast, the well hydrophobized silica leads to a liquid silica-in-oil diqrersion. 

Now we consider simulations of the atomic structure of amorphous oxides especially at their surfaces. We begin with the best studied structure of amorphous silica. The structure of the bulk amorphous silica is generally obtained in computer simulation by first simulating liquid silica at a high temperature of about 4000 K [6] or even 6000 K [7]. This stage is followed by the simulation of quenching when the temperature steadily decreases at the rate of 10 lO " K/s. This rate of cooling is the lowest practically achievable in... 

Knoevenagel condensation of aldehydes/ketones with malonitrile and ethyl cyanoacetate. The reactions were carried out under homogeneous and biphasic conditions, including the use of liquid-silica supported IL, with the biphasic system employing cyclohexene as the second phase. Although supported ILs showed a reduced initial activity, in general an excellent recyclability was observed, with the reaction repeated over five times without leaching of the IL into the extractant phase or reduction in activity. 

Ionic liquid/silica gel, acetone, water, 89-96% yield. "... 

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