Scaling layers, morphology

Overall, the correlation functions discussed in detail in Malek et al. provide valuable structural information at the nanometer scale that allows refining the picture of fhe phase-segregafed cafalysf layer morphology, lonomer... 

Sandgren, C.D., Hall, S.A. and Barlow, S.B. (1996) Siliceous scale production in chrysophyte and synurophyte algae. 1. Effects of silica-limited growth on cell silica content, scale morphology, and the construction of the scale layer of Synura petersenii. Journal of Phycology, 32, 675—692. 

Fig. 25 Three-layer morphology observed by SEM for a cross-section of porous-NC (freeze-dried NC gel In liquid nitrogen). Fine-porous, dense, and coarse-porous layers were observed from the outer surface to the Interior. Scale bar Indicates 500 )jm. Reprinted from Haraguchi and Matsuda [110], Copyright 2005, with permission of ACS...

Different phase separated morphologies can be found in different polymer solvent systems. The pattern formation consists of several stages. In the initial stage, phase separation results in a layered morphology of the two solvent swollen phases. As more solvent evaporates, this double layer is destabilized in two ways (1) capillary instability of the interface, and (2) surface instability. Each of the mechanisms results in different morphological length scales. Core shell spherical domains in phase-separated ternary systems have also been found. The shell thickness can be a few nanometers. 

Morphology It is the study of the physical form or structure of a material the physical microstructurc of a bulk polymer. Common units arc lamella, spherulitc, and domain. In turn there arc thermoplastic (TP) and thermoset (TS) plastics. Lamella is a thin, flat scale layer of polymers. Spherulitc is a rounded aggregate of radiadng lamellar crystals. Spherulites exist in most crystalline plastics and usually impinge on one another to form polyhedrons. They range in size from a few tenths of a micron in diameter to several millimeters. Domain is a microphase of one polymer in a multiphase system. 

At the mesoscopic scale, interactions between molecular components in membranes and catalyst layers control the self-organization into nanophase-segregated media, structural correlations, and adhesion properties of phase domains. Such complex processes can be studied by various theoretical tools and simulation techniques (e.g., by coarse-grained molecular dynamics simulations). Complex morphologies of the emerging media can be related to effective physicochemical properties that characterize transport and reaction at the macroscopic scale, using concepts from the theory of random heterogeneous media and percolation theory. 

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