Morphology interface

For n-type doping densities below 1017 cm-3 and an anodization bias above 10 V, avalanche breakdown becomes relevant. The interface morphology generated in this regime is very complex and shows large etch pits, macropores and mesopores. The formation of this structure is not understood in detail. A hypothetical model will be discussed in Section 8.5. 

Fig. 5..11. Scanning electron micropliotograplis of the interface morphology ft)r (a) imcoatcil SiC monolilamcnt and (b) Ti 6AI-4V coated SiC monofilament after exposure at 1070°C for 2 h. After Gtio el al. (199.1). Reproduced by permission of Blackwell Science Ltd.

Let us assume that a small bulge appears on a rough, curved interface, and that for some reason the interface morphology is altered. Intervals between the lines of equal temperature or concentration become narrower at the bulge hence, the... 

Figure 11-13. Survey of experimental interface morphologies which depend on the initial compositions (x and y) of the reactants (spinel and sesquioxide) in the quasi-ternarv system A-B-C = Fe304-Mn,04-Cr203, corresponding to Figure ll-12a.

A gradient of electrical potential constitutes the classic (external) force field for ionic solids. Let us study the effect of this electric field on the interface morphology and stability. The thermodynamic driving force in ionic crystals is Vi/,(= +... 

With an open system to which electrodes are attached, we can study the stability of interface morphology in an external electric field. A particularly simple case is met if the crystals involved are chemically homogeneous. In this case, Vfij = 0, and the ions are essentially driven by the electric field. Also, this is easy to handle experimentally. The counterpart of our basic stability experiment (Fig. 11-7) in which the AO crystal was exposed to an oxygen chemical potential gradient is now the exposure of AX to an electric field from the attached electrodes. In order to define the thermodynamic state of AX, it is necessary to apply electrodes with a predetermined... 

Microscopic Analysis of Melt/Solid Interface Morphology During Solidification Studies of Cells and Dendrites... 

The RMD algorithm is implemented as an additional step at the end of each time step in a conventional MD simulation. Thus the interaction potentials used in the reactive simulation are non-reactive and are the same as those used to generate the membrane and interface morphologies described above. 

The results described above and previously reported findings lead to several interesting hypotheses about the evolution of scale and interface morphologies at very high temperatures, and the influence of the substrate on this evolution. The present... 

The properties of thin films are primarily determined by the type of chemical element or compound they comprise and by the film thickness. Their optical, electro-optical, electrical and mechanical behaviour is also determined by structure, microstructure, surface and interface morphology, chemical composition, purity and homogeneity. These are strongly influenced by the film preparation method, the chosen parameters, and by post-deposition treatments. 

Relation Between Temperature Gradient, Interface Morphology, and Impurity Distribution. The shape of the phase boundary is related to the distribution of lines of heat flow. Heat flow characteristics not only determine the rate of phase change but also the rate of transfer of solute atoms as well as their spatial distribution within the phases. 

Alternatively, delamlnatlon may not be related directly to permeation, but may be due Instead to thermal and/or UV effects that are followed by the corrosive failure. Some studies and models Indicate that the polymer/metal Interface morphology, and the changes In the morphology with exposure to the environment, play a key role In corrosion rates. These characteristics may be even more Important In corrosion control than either the diffusion of vapors through the pol5mier or the Inherent corrosion resistance of the metal. 

S.Goel and A. Gupta synthesized polypyrrole samples of different nanodimensions and morphologies by time dependent interfadal polymerization reaction. Pure chloroform was used as solvent for pyrrole and ammonium persulphate dissolved in HCl was used as the oxidizing solution. The polymerization occurred in the interface of organic and aqueous phases and polypyrrole was formed as thin layer on the interface. Morphology study of polypyrrole nanoparticles was done by scanning electron microscopy and transmission electron microscopy. 

These concerns can be addressed partially through the use of mixed-matrix membranes [77-79]. Dispersing the microporous material in the form of small particles within a polymeric matrix simplifies membrane formation dramatically. Mixed matrix materials possess transport properties intermediate between those of the polymer matrix and the microporous particle and operating temperatures are limited by the thermal stability of the polymer matrix. However, proper selection of the matrix, control of particle volume fraction, and development of a membrane formation process can yield materials with properties that approach those of the particles [77-78]. Special attention must be given to the particle-polymer interface. If the interface morphology is uncontrolled, the matrix may 1) not wet the particle leaving a non-selective void around the particle, 2) enter the particle and block pores, or 3) rigidify around the particle and block access to it [79]. 

Renaud, G., Lazzari, R., Leroy, F. Probing surface and interface morphology with grazing incidence small-angle Y-ray scattering. Surf. Sci. Rep. 64, 255 (2009)... 

The problem of interface morphology (planar or curved interface, cellular structure unstationary shape, chaotic, turbulent) as a function of the control parameters. 

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