Homogeneity, microscopic

The consolidated titanate waste pellets are similar in appearance to their glass counterparts, i.e., both are dense, black and apparently homogeneous. Microscopic analyses, however, reveal important differences between these two waste forms. While little definitive work has been done with glassy waste forms, it is apparent that several readily soluble oxide particulates of various nuclides are simply encapsulated in the glass matrix. The titanate waste form has undergone extensive analyses which includes optical microscopy, x-ray, scanning electron microscopy, microprobe, and transmission electron microscopy (l ) The samples of titanate examined were prepared by pressure sintering and consisted of material from a fully loaded titanate column. Zeolite and silicon additions were also present in the samples. 

Fig. 2. Illustration of the difference between homogeneous (microscopic) and inhomogeneous (macroscopic) hne width.

Macerals Homogeneous microscopic constituents of coals, analogous to minerals in inorganic rocks. 

Field analogues should be based on reservoir rock type (e.g. tight sandstone, fractured carbonate), fluid type, and environment of deposition. This technique should not be overlooked, especially where little information is available, such as at the exploration stage. Summary charts such as the one shown in Figure 8.19 may be used in conjunction with estimates of macroscopic sweep efficiency (which will depend upon well density and positioning, reservoir homogeneity, offtake rate and fluid type) and microscopic displacement efficiency (which may be estimated if core measurements of residual oil saturation are available). 

Analysis of microscopical data shows that all samples synthesized have the particles of spherical form. On the electron microscopical level on the sorbent surface the nanostructure in the form of fine elements (100-500 nm). For hybrid sorbents synthesis these elements are smaller and more homogeneous due to more effective conditions of synthesis (mixing of PES and ZrOCl, solutions, treatment of prepared MSS in ZrOCl, solution). 

Steel alloyed with 1% A1 is more resistant to oxidation at high temperatures. The macro- and microscopic homogeneity of the distribution of all elements is better for powder metallurgical, hot isostatically pressed steels. Combining these advantages should result in better performance of high-speed steels. 

In a uniaxial tension test to determine the elastic modulus of the composite material, E, the stress and strain states will be assumed to be macroscopically uniform in consonance with the basic presumption that the composite material is macroscopically Isotropic and homogene-ous. However, on a microscopic scSeTBotFTfhe sfre and strain states will be nonuniform. In the uniaxial tension test,... 

Molecular dynamics, in contrast to MC simulations, is a typical model in which hydrodynamic effects are incorporated in the behavior of polymer solutions and may be properly accounted for. In the so-called nonequilibrium molecular dynamics method [54], Newton s equations of a (classical) many-particle problem are iteratively solved whereby quantities of both macroscopic and microscopic interest are expressed in terms of the configurational quantities such as the space coordinates or velocities of all particles. In addition, shear flow may be imposed by the homogeneous shear flow algorithm of Evans [56]. 

Electron and optical microscopes are being used to see blend homogeneity. Elastomer-plastic blends are somewhat easier to identify than elastomer-elastomer blends because normal staining techniques, e.g., osmium tet-raoxide, can be used in the case of plastic-elastomer blends. Normally, there are two methods that are followed for examining the blend surface by electron microscopy. 

In this section the interaction of a metal with its aqueous environment will be considered from the viewpoint Of thermodynamics and electrode kinetics, and in order to simplify the discussion it will be assumed that the metal is a homogeneous continuum, and no account will be taken of submicroscopic, microscopic and macroscopic heterogeneities, which are dealt with elsewhere see Sections 1.3 and 20.4). Furthermore, emphasis will be placed on uniform corrosion since localised attack is considered in Section 1.6. 

One of the principal themes of this book is the use of CA in modeling real physical systems and dynamics. To this end, it is important to address the question of what fundamental properties of physical systems can be appropriately abstracted from nature and embodied within abstract CA constructs. As observed earlier, some properties such as homogeneity and locality are automatically built in on the generic level. Another such property, namely the reversibility of microscopic dynamics, which plays such a fundamental role in physics, has its analogue in CA dynamics as well. 

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