3D imaging technique

The corresponding 3D imaging techniques are called single photon emission computed tomography (SPECT) and positron emission tomography (PET). As PET is discussed in detail elsewhere in this book (see Part V, Chapter 5), we will focus here on SPECT. 

Being intrinsically a 3D imaging technique, digital holography offers a great scope for solving... 

Perman, W., Heiberg, E., Grunz, J., et al. (1994). A fast 3D imaging technique for performing dynamic Gd-enhanced MRI of breast lesions, Mag. Reson. Imag., 12 545-551. 

In this chapter we will review the specific technical requirements necessary to obtain adequate studies of the upper gastrointestinal tract from esophagus to small bowel passing through the stomach and the clinical applications of 3D imaging techniques. 

Atomic force microscopy (AFM) is a high-resolution 3D imaging technique capable of measuring topographical features to less than 1 nm (Binning et al., 1986). A cantilever with a sharp tip is brought into contact with the surface, in which the force between the tip and the surface results in deflection of the cantilever. The cantilever is rastered over... 

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 . 

Atomic force microscopy (AFM) is a commonly employed imaging technique for the characterization of the topography of material surfaces. In contrast to other microscopy techniques (e.g., scanning electron microscopy), AFM provides additional quantitative surface depth information and therefore yields a 3D profile of the material surface. AFM is routinely applied for the nanoscale surface characterization of materials and has been previously applied to determine surface heterogeneity of alkylsilane thin films prepared on planar surfaces [74,75,138]. 

For the detailed study of reaction-transport interactions in the porous catalytic layer, the spatially 3D model computer-reconstructed washcoat section can be employed (Koci et al., 2006, 2007a). The structure of porous catalyst support is controlled in the course of washcoat preparation on two levels (i) the level of macropores, influenced by mixing of wet supporting material particles with different sizes followed by specific thermal treatment and (ii) the level of meso-/ micropores, determined by the internal nanostructure of the used materials (e.g. alumina, zeolites) and sizes of noble metal crystallites. Information about the porous structure (pore size distribution, typical sizes of particles, etc.) on the micro- and nanoscale levels can be obtained from scanning electron microscopy (SEM), transmission electron microscopy ( ), or other high-resolution imaging techniques in combination with mercury porosimetry and BET adsorption isotherm data. This information can be used in computer reconstruction of porous catalytic medium. In the reconstructed catalyst, transport (diffusion, permeation, heat conduction) and combined reaction-transport processes can be simulated on detailed level (Kosek et al., 2005). 

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