Interpretable structure image

This condition can be obtained in a defocused condition of the objective lens. As a result, an image of phase contrast may be interpreted in terms of periodic structures of a crystalline solid. Such an image of phase contrast is called the interpretable structure image. 

TEM is still the most powerful technique to elucidate the dispersion of nano-filler in rubbery matrix. However, the conventional TEM projects three-dimensional (3D) body onto two-dimensional (2D) (x, y) plane, hence the structural information on the thickness direction (z-axis) is only obtained as an accumulated one. This lack of z-axis structure poses tricky problems in estimating 3D structure in the sample to result in more or less misleading interpretations of the structure. How to elucidate the dispersion of nano-fillers in 3D space from 2D images has not been solved until the advent of 3D-TEM technique, which combines TEM and computerized tomography technique to afford 3D structural images, incidentally called electrontomography . 

Figure 4, Area of benzene covered gold (111). surface, for two different objective len.s defooi a.s required for unique image interpretation (see 2 ). Tri a) the gold atomic columns are black, in b) white. Moire fringes, rather than any true structural image, result from the benzene monolayer. Simulations (right) have benzene overlay on top surface only.

The results for the apparent radius of STM images for individual states can be used to interpret experimental images directly. For surfaces with complex periodic structures, such as Si(lll)-7 X 7 and Si(lll)-5 X 5, the concept of imaging individual atomic states is a much better description than surface Bloch functions. For adatoms and defects, the individual state description is the only possible one. 

The purpose of doing STM is to learn about surface structures, and the tip as such is regarded as an uninteresting probe. In this sense, it is a problem that the electronic structure of the tip is contained in the formula for the tunnel current in the original work by Bardeen 58). Tersoff and Hamann 59,60), however, extended Bardeen s formalism and showed by simple, yet relevant approximations that the impact of the unwanted electronic structure of the tip is in many cases less pronounced for typical tunneling parameters. Fortunately, the Tersoff-Hamann model provides a simple conceptual framework for interpreting STM images, and therefore it is still the most widely used model. 

Fig. 2.14 Structure image of W,gO52 in a series of W O3 derived by the shear operation (130)5[li0]. ° For the interpretation of the electron micrograph, see text.

Fig. 2.15 Structure image of an isolated single shear plane of (120) from a fragment of slightly reduced WO3 (a) and structure models used for interpretation (b) and (c)," (see text).

Fig. 2.29 Structure image of TiNbj Ogj. The inset shows the calculated image, which is in good accordance with the observed one. The marks E - and F - are referred to in Fig. 2.26. For the interpretation of the image, see text.

Microspectrometry is an indispensable technique in criminalistic analyses, being a combination of optical microscopy and spectrometry. Microscopy creates, records and interprets magnified images, whereas spectrometry uses emission, absorption and reflection of radiant energy by matter to determine its structure, properties and composition. On the basis of the type of energy applied, microspectrometry can be divided into IR, visual and ultraviolet (UV-vis), and Raman microspectrometry. This group also includes X-ray microspectrometry, in which an electron microscope takes the place of an optical microscope. Infrared and Raman microspectrometry enable determination and comparison of the chemical composition of studied samples UV-vis microspectrometry serves to compare the colour of samples in an objective way that is independent of the observer and X-ray microspectrometry allows determination of the elemental composition. 

Often, the graphical format allows the connection table to be stored and transferred transparently with the image—through the computer s clipboard, for instance. This allows the receiving program to "interpret" the image as a chemical structure and manipulate it accordingly. 

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