Image, bright-held

In Figure 14(a) the bright-held TEM cross-sectional image of the reference AuAg sample is shown. The size distribution of the clusters has an average diameter = 11.7nm and a standard deviation of the experimental bimodal distribution o- = 6.4nm. The effect of... 

Detection of the specimen image depends on the relative intensity differences, and therefore on the amplitudes, of the particle and surround (P and S) waves. If the amplitudes of the particle and surround waves are significantly different in the intermediate image plane, then the specimen acquires a considerable amount of contrast and is easily visualized in the microscope eyepieces. Otherwise, the specimen remains transparent and appears as in an ordinary bright-held microscope. 

Figure 2.3. A schematic diagram of bright-held (bf) TEM imaging. A dark-held (df) image is formed using a diffracted electron beam.

Figure 4.3. C0-ALPO5 catalyst (with (Co/Co + Al) = 0.036) (a) an SEM image (b) an HRTEM image (inset— simulated structure) and (c) x-ray elemental map of Co-ALPO indicating uniform distribution of the elements Al, P and Co. The bright-held image is also shown.

Figure 14a is a typical TEM micrograph of Pt/C shadowed standard-size PTFE dispersion particles, (here sample G) with dark-field images of unshadowed particles in the insets typical BFDC micrographs of several standard-size DuPont dispersion particles are shown in Fig. 14b and c. The dark-field micrographs, taken with 100 reflections, are similar to the bright-held ones except... 

Figure 7.22. Elemental dot-maps. Shown is (a) elemental concentrations of Si, O, and F (as white pixels) overlaid onto the SEM image of a Nafion resin/sihca composite[33l (b) bright-held STEM image of a GaN/AlN/AlGaN nanowire cross section, with elemental mapping of Ga, N, and A1 (scale bar is 50nm).[34l...

Figure 7.27. Energy-filtered TEM showing silica nanoparticles embedded within an organic coating. The conventional bright-held TEM image Geft) shows little/no contrast relative to the EF-TEM image (right).[50]...

Figure 1.25 Comet tailing generated by polishing on specimen surface (a) bright-held image and (b) Nomarski contrast image. (Reproduced with permission of Struers A/S.)...

Figure 3.19 Bright-held images of aluminum alloy. The contrast difference between (a) and (b) is generated by tilting the specimen. Individual grains are marked with numbers. (Reproduced with permission from M. von Heimandahl, Electron Microscopy of Materials, Academic Press, New York. 1980 Elsevier B. V.)...

Figure 3 Radiation-induced metal clusters, (a) Silver nanoclusters stabilized by PVA (10 nm). (b) STM imaging ofa single duster of the blue sol of silver oligomers Agd formed by y irradiation (n = 4). (c) Clusters ofAg, partially reduced by irradiation and then chemically developed by EDTA. (100 nm large and 15 nm thick), (d) TEM bright-held Image ofNi , PVA clusters (5 nm). (e) Two-dimensional self-assembled array of gold dusters (PVA) on mica with remarkable homodisperse size (5 nm). (f) Monocrystalline Pt nanotubes with CPCI (10 nm diameter and a few 100 nm long), (g) Pt nanorods with CTAB (3-4 nm thick and 20-40 nm long).

FIGURE 1.18 TEM bright-held images and SAD pattern for synthesized SrTiOj (120 h milling) (a) and (b). (Reprinted from Sensors /., 5, Hu Y, Tan O. K., Cao W., and Zhu W., Fabrication characterization of nano-sized SrTiOj-based oxygen sensor for near-room temperature operation, IEEE 825-832, 2005 with permission from Elsevier.)... 

Spiral Inertial Microfluidic Devices for Cell Separations, Fig. 4 (a) Photograph of the 5-loop spiral microchannel with two inlets and eight outlets fabricated in PDMS [3], (b) Bright-held and epifluorescent images... 

When the lenses are defocused, so that a small crossover is formed before or after the specimen, the central spot of the CBED pattern will become a bright-held shadow image of the specimen and each diffraction spot will become a dark- held shadow image showing the variation of intensity within the illuminated zone, this is the afore mentioned a) variant. 

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