Bright field imaging composites

Fig. 4.29. EDXS line-profile analysis across the interfacial region of a C-fiber reinforced SiC composite and corresponding TEM bright-field image.

The transmission electron microscope is now well established as a useful tool for the characterization of supported heterogeneous catalysts(l). Axial bright-field imaging in the conventional transmission electron microscope (CTEM) is routinely used to provide the catalyst chemist with details concerning particle size distributions, 3), particle disposition over the support material(2-6) as well as particle morphology(7). Internal crystal structure(8-10), and elemental compositions(ll) may be inferred by direct structure imaging. 

Figure 10.1.10, a and b, shows the TEM bright-field images with different magnifications for the Pt/carbon tube composite prepared at 500°C. These two images exhibit the presence of uniform carbon nanotubes, and their outer diameter and... 

Fig. 10.1.14 TEM photographs of the Fe/carbon nanotubc composites before the alkali treatment (MOCVD temperature, 400°C MOCVD period, 24 h ferrocene vapor pressure, 0.1 kPa (a) a bright-field image and (b) SAD pattern for the nanotubes from the image (a). (Front Ref. 41.)...

The nanotube network was successfully investigated in our laboratory by Dalmas et al. (63), in terms of distribution of radius of curvature. Indeed, the 2D apparent nanotube segment curvature radius distribution was then measured on TEM bright field images acquired on the composites (see Figure 3.8). The experimental curvature... 

Figure 3.11. TEM bright-field images of composites made of polystyrene and (a) raw and (b) polystyrene-grafted nitrogen-doped multiwalled nanotubes (69).

FIGURE 11. TEM bright field image from cross-section of Hi-Nicalon/BN/SiC/BSAS composite showing (a) multiple BN layers and (b) coarsening of the outer three BN layers. The iimer BN and the SiC interface layers are unaffected. (Reprinted, from reference 26, with kind permission from Elsevier). 

Fig. 2. TEM bright-field image of ZrC/Ti3AlC2 composite and the relative content of Al, Ti and Zr along the line across the interface.

Spiral Inertial Microfluidk Devices for Cell Separations, Fig. 5 (a) Image of the spiral sorting device [11, 12]. (b) Bright-field image of the outlet system, (c) At 1.8 mL/min flow rate (FI), two focused streams are observed, the narrow stream in the middle of the channel is formed by 7.32 pm particles, and the broad stream near the iimer channel wall is the composite of three streams of 10, 15, and 20 pm particles. Particles in the range of 10-20 pm are obtained out of the first outlet, and the 7.32 pm particles are obtained from the second and third outlets [11]. (d) Fluorescent image of the focused streams of all three particles, 10,15, and 20 pm in diameter, at the flow rate of 2.2 mL/min (F2) [11]. (e) Normalized... 

Figure 3, (a) Low magnification cross-sectional bright field image, (b) the corresponding HADDF image of the PEO layer in sample B and (c) EDX compositional point analysis of the PEO layer. 

Fig. 2. Bright field image of bulk // Cr-doped alloys after leaching. EDX spectra showing the Inhomogenelty of Al composition.

Fig. 3 (left) TEM bright-field and (middle) dark-field images, and (right) selected area diffraction pattern from a 20 vol% Si3N4/5052 Al composite at 548 °C. (from Ref. [8,9])... 

In some studies, a statistical description of the nanotube dispersion state was obtained from TEM images. For example, Uchida et al. (56) measured the diameter distribution of SWNT bundles in poly(acrylonitrile), with and without a purification treatment involving sonication in methanol. The different bundle diameter distributions (especially the mean diameter) could explain the different composite tensile moduli. Fornes et al. (57) also determined the diameter distribution of SWNTs bundles in a polymer matrix (namely polycarbonate). To improve the contrast in the bright-field TEM images and better measure the bundle diameter, they dissolved the polymer in chloroform and studied the remaining SWNT network. 

Figure 4.3. Bright field optical microscope images for epoxy composites containing 0.05 wt% SWNT (a), 0.05 wt% SWNT, and 2 wt% clay (c), images (b) and (d) are the same respective positions, but under cross-polarized light condition. Reprinted with permission from ref (41).

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