Alumina microscopy images

Figuic 4.5 Transmission electron microscopy image of well dispersed boehmite particles as a precursor to fine-pore alumina membranes... 

Figure 4.6 Transmission electron microscopy image of a very thin, partially calcin alumina membrane with nanometer-sized pores...

FIGURE 6.7 Scanning electronic microscopy images of inorganic membrane porous structures (a) asymmetric alumina (b) asymmetric carbon structure (c) homogeneous alumina structure and (d) homogeneous glass structure. 

Fig. 21.6. Scanning electron microscopy image of an alumina template.

This advantage can be used for growing nanowires (wires with nanometric diameter). Nanoporous membranes that can be fabricated by the anodic oxidation of aluminum are appropriate templates. This process leads to the formation of an alumina layer with parallel nanopores, as shown in Fig. 15A, which can then be filled by electrodeposition. Fig. 15B shows a schematic view of a multilayer nanowire and Fig.l5C a transmission electron microscopy image of a Cu/ CuCoNi layered nanowire grown in the nanopores. 

Fig. 6 (A) Anodized alumina, posted microreactor used for reforming of ammonia to hydrogen. (B) Optical microscope image of the microreactor posts. (C) Scanning electron microscopy image of a microreactor postsurface illustrating the porosity of the anodized surface. (View this art in color at www.dekker.com.)...

Figure 1.3 High-resolution transmission electron microscopy images of the grain boundaries of alumina samples sintered with 5 wt% calcium silicate additives. The numbers in the names ofthe specimens denote the molar...

Figure 13. Scanning Electron Microscopy image (Back scattered electrons mode) of a zirconia toughened alumina nano composite, showing the narrow distribution of well dispersed zirconia particles in an alumina matrix [39],...

Figure 12.2 Transmission electron microscopy image of 5% alumina-doped hydroxyapatite powders calcined at 650°C for 1 h with a Ca sucrose ratio of 1 15.

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). 

Figure 4.7 Three-dimensional image of a gamma-alumina membrane by atomic force microscopy [Bottinoeial., 1994]...

FICURE 10.11 AFM topographic and scanning electron microscopy (SEM) images from the external surface of siUcaUte layers over seeded nonporous alumina substrates after synthesis time of (a, b) 35 min and (c, d) 50 min. 

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