Sponge-like microstructures

Transparent anatase Ti02-based multilayered photocatalytic films synthesized via a sol-gel process on porous alumina and glass substrates showed a sponge-like microstructure and a mean crystallite dimension of ca. 8 nm [152]. Doping such films with iron(III) impeded the photocatalytic activity. 

Figure 6.1 shows a schematic representation of the pseudo three-component phase diagram of a typical (surfactant/cosurfactant)-oil-water system. Depending on formulas, fine oil droplets dispersed in the continuous aqueous phase [O/W (or direct) microemulsion] or water droplets in the continuous oily phase [W/O (or inverse) microemulsion] are obtained. Furthermore, the intermediate region between the OAV microemulsion phase and the W/O microemulsion phase is characterized by a bicontinuous microstructure in which the aqueous and oily microdomains are interconnected with each other [13, 14]. The presence of such a middle phase in the colloidal system was verified by literature data [15]. It was shown that the oil-water interfacial layer in the bicontinuous microstructure has a zero mean curvature (i.e., it is flat on the average), and this sponge-like microstructure is completely disor-... 

It has been found that a decrease in the initial porosity in the food may reduce oil absorption (Pinthus et al., 1995). However, as explained by the authors, crust formation plays an additional and fundamental role as soon as frying commences. As the moisture turns to steam and exits the product, it leaves behind a sponge-like tunnel network, which constitutes the oil reservoir. In accordance, the microstructure of the crust region,... 

Suspension polymerization, in which a mixture of monomers and crosslinking reagents is polymerized in the presence of an inert solvent, is used to prepare porous polymer beads [148]. The microstructure of the gel, formed within the droplet in the early stages, gradually grows into a sponge-like structure, with inert solvent filling the space between the microstructures. After solvent removal, the porous structure remains, pro-... 

In contrast, the finger-like microvoids or channels inside microstructured ceramic hollow-fiber membranes significantly reduce mass transfer resistance, and the thin sponge-like skin layer can fimction as a separation layer. Thus, a single-step viscous... 

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