Particles, transmission electron micrographs

Figure C2.17.2. Transmission electron micrograph of a gold nanoneedle. Inverse micelle environments allow for a great deal of control not only over particle size, but also particle shape. In this example, gold nanocrystals were prepared using a photolytic method in surfactant-rich solutions the surfactant interacts strongly with areas of low curvature, thus continued growth can occur only at the sharjD tips of nanocrystals, leading to the fonnation of high-aspect-ratio nanostmctures [52].

Figure C2.17.4. Transmission electron micrograph of a field of Zr02 (tetragonal) nanocrystals. Lower-resolution electron microscopy is useful for characterizing tire size distribution of a collection of nanocrystals. This image is an example of a typical particle field used for sizing puriDoses. Here, tire nanocrystalline zirconia has an average diameter of 3.6 nm witli a polydispersity of only 5% 1801.

Fig. 13. Transmission electron micrograph (tern) showing dislocations in aluminum in the region near a siUcon carbide particle, SiC. ...

We measured the dispersion of Pt (impregnated from a chloroplatinic acid precursor, calcined at 450 C and reduced at 500 C) on a series of Nd203-loaded silica-aluminas (Fig. 8). We find, unexpectedly, that dispersion increases with increasing rare earth oxide loading up to about 18% Nd203, where it plateaus at between 40 and 50%, compared to 10% with unmodified Si-Al. This compares with dispersions of -60-80% measured on similarly Pt-loaded transitional AI2O3 catalysts. Transmission electron micrographs confirmed the decrease in particle size with rare earth content on Si-Al. 

Figure 6 shows transmission electron micrographs of Au particles supported by (a) monocrystalline ellipsoidal (B), (b) monocrystalline pseudocubic, and (c) monocrystalline platelet-type hematite particles (see also Figure 5 for Au particles on polycrystalline ellipsoidal (A) particles). Figure 7 shows Au particles deposited on (a) a-FeOOH, (b) P-FeOOH, (c) ZrOj (A), (d) ZrOj (B), and (e) Ti02 (anatase). 

Figure 5. Transmission electron micrographs of Au nanoclusters deposited on the surfaces of the polycrystalline ellipsoidal hematite particles. The left photograph is a close-up view of the right one.

Figure 2. Transmission electron micrographs of the copper nanocube from the spherical seed particles. Conditions total copper concentration 2xl0 M and [M ]/[M ] = 1 99. (Reprinted from Ref [30], 1998, with permission from Current Science Association.)...

Fig. 7.8 Transmission electron micrograph of nano CaC03 particles synthesized using polyacrylic acid as surfactant using sonocrystallization method [43]...

Figure 7.1 Transmission electron micrographs of rhodium particles supported on silica spheres (from Datye and Long [7]). 

Figure 7.5 Transmission electron micrographs of a Pd/AFC), catalyst in bright (above) and dark field (below). The latter shows enhanced contrast for the Pd particles as well as better resolution (from Freeman et al. [14]).

Figure 7.6 Transmission electron micrographs of An particles in different orientations on a crystalline MgO support (from Giorgio el al. 116]).

Figure 10.6. Transmission electron micrographs of polystyrene particles prepared by dispersion polymerization in Freon 113 and stabilized by Fluoro-PSB-IV (a) Sample 2 (b) Sample 3.

FIGURE 9.24 Transmission electron micrograph of soot particles collected from a laminar jet diffusion flame burning kerosene in air. 

Some typical transmission electron micrographs of these polystyrene lattices are shown (Sample 2 and Sample 3) in Figure 10.6. The effects ofthe amount of stabilizer S is the relative amount of stabilizer) on the particle size is strong the more stabilizer applied, the smaller the particles are. It must be emphasized that this effective stabilization of nanopowders by our fluorinated block copolymers is not restricted to polymerization processes, but can be generalized to the fabrication of all organic nanopowders in media with low cohesion energy density, e.g., to the dispersion of dyes, explosives, or drugs. 

Fig. 1. Transmission electron micrograph of RBL-2H3 cells with colloidal gold conjngated to a monoclonal antibody against the IgE receptor. (A) Gold con-jngate is localized primarily in coated pits. (B) Five minntes after exposing cells to antibody-coated gold, gold particles are localized in early endosomes. Bar = 0.5 pm.

Fig. 4 Transmission electron micrographs of a highly facetted mostly triangular gold particles, b a hexagonal particle, c electron diffraction pattern of the triangular particle showing that it is a single crystal. Diffraction from the (111), (220), (311), (331), (422) planes are identified...

Fig. 1.4.2 Transmission electron micrograph of Si02 particles produced at Wo = 5 in 0.10 mol kg-1 polyoxyethylene(6) nonylphenyl ether-cyclohexane system. [TEOS] 0.10 mol kg-1 [NH3]/[surfactant] = 0.5.

Fig. 1.5.10 Transmission electron micrographs of two different thicknesses of polyurea coating on titania core particles. In each case the titania was obtained under the same conditions as those in Fig. 1.5.3. HDI was kept at 80°C at flow rates of (A) 0.19 dm3 min-1 and (B) 0.42 dur1 min-1. The flow rate and temperature of ethylenediamine were held constant at 44.3 cmJ min-1 and 25°C, respectively. (From Ref. 39.)...

Figure 2.1.6 shows the results of such a continuous synthesis process. It shows the variation of the mean particle size during the experiment. The error bars indicate the standard deviation of the particle size distribution of each sample based on the transmission electron micrographs (number distribution). The experiment was performed under the following conditions (A) ammonia, water, and TEOS concentrations were 0.8, 8.0, and 0.2 mol dm-3 7", = 273 K, T2 = 313 K total flow rate was 2.8 cm3 min-1 100 m reaction tube of 3 mm diameter residence time 4 h and (B) ammonia, water, and TEOS concentrations were 1.5,8.0, and 0.2 mol dm- 3 Tx = 273 K, T2 = 313 K total flow rate was 8 cm3 min-1 50 m reaction tube of 6 mm diameter, residence time 3 h. Further details and other examples are described elsewhere (38). Unger et al. (50) also described a slightly modified continuous reaction setup in another publication. 

Fig. 2.1.7 Transmission electron micrograph of StOber silica particles.

Fig. 2.1.8 Transmission electron micrograph showing the internal structure of Stober silica particles. (From Ref. 51.)...

Fig. 3.3.2 Transmission electron micrographs showing the rapid growth process of the uniform CdS particles with aging time under the standard conditions (A) 15 s, (B) 30 s. (C) 1 min. and (D) 1 h. (From Ref. 2.)...

Figure 3.3.5 shows a high-resolution transmission electron micrograph showing a close-up view of a part of a CdS particle. One may find that the particle consists of randomly oriented crystallites, as is obvious from the clear lattice image of each... 

Fig. 4.3.1 Transmission electron micrograph of AgCI particles precipitated in 0.10 mol kg-1 cyclohexane system. Wo = 25 [Ag+] and [Cl ]/[Aerosol OT = 0.01.

Fig. 4.4.2 Transmission electron micrograph of Agl ultrafine particles prepared with an initial [I ]/[RSH] ratio of 9.0. (From Ref. 9.)...

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