Transmission electron microscopy pictures

Determined by inductively coupled plasma-mass spectrometry of acid digested catalyst samples Calculated from X-ray diffraction peak broadening at (101) foranatase and (110) formtile TiOa Mean particle diameter measured from transmission electron microscopy pictures of gold catalysts... 

Transmission electron microscopy pictures were taken using a JE0L 100 CX microscope. For some samples lateral micro-analysis of thin sections of zeolite was carried out using a HB-5 VG microscope equipped with EDX accessory at IFP (11). 

Fig. 5.5. Transmission electron microscopy picture of RuxSey cluster-like materials, (a) in form of powder (b) from a colloidal solution (xylene).

Picture 1. Transmission Electron Microscopy picture of an alumi--nium coating (25 nm thick) on a PP film... 

We note in passing that the recent transmission electron microscopy pictures of Cgo films by Wang and Buseck show evidence of Cjo-Cgo coalescence to form cylindrical bucky tubes in the solid Film, presumably triggered by the 400-keV electron beam. We wonder if metal atom encapsulation events would occur under similar circumstances with metal-doped fullerene films. 

From transmission electron microscopy pictures, it appeared that the graphite leaflets were identical in the starting material and in the supported catalysts and that... 

Fig. 20 Transmission electron microscopy pictures of nanocomposite from TFX and 10 wt% particles. Reprinted by permission from ref. [85]. Copyright 2006, National Academy of Sciences, U.S.A.

The easiest way to carry out heterophase polymerization is to mix water and a monomer, say styrene, which is able to undergo thermal polymerization, in a vessel at elevated temperatures. After a couple of hours, (the time depends on the temperature) the mixture becomes turbid because of the formation of polystyrene particles. Figure 19 shows a transmission electron microscopy picture of polystyrene particles obtained in this simple way. Although the amount of polystyrene formed was low and the reproducibility of this procedure very bad, a heterophase polymerization took place, and this offers a nice example of how easily heterophase polymerization can be carried out. 

Fig. 19. Transmission electron microscopy pictures of polystyrene particles obtained by thermal poljmierization at 90° C in an all-Teflon (DuPont) reactor after duration of 7 h the bar indicates 3.5 p,m.

Pig. 21. Transmission electron microscopy pictures of the small particle size fraction of the dispersion shown in Figure 20a. Sample C (potassium peroxodisulfate) b Sample D (dibenzoyl peroxide) the bars indicate 1 /.tm. 

Electrocatalysts for the Oxygen Reaction, Core-Shell Electrocatalysts, Fig. 1 (a) Schematic representation of a core-shell nanoparticle, (b) High-angle annular dark field scanning transmission electron microscopy picture... 

The picture of cement microstructure that now emerges is of particles of partially degraded glass embedded in a matrix of calcium and aluminium polyalkenoates and sheathed in a layer of siliceous gel probably formed just outside the particle boundary. This structure (shown in Figure 5.17) was first proposed by Wilson Prosser (1982, 1984) and has since been confirmed by recent electron microscopic studies by Swift Dogan (1990) and Hatton Brook (1992). The latter used transmission electron microscopy with high resolution to confirm this model without ambiguity. 

Fig. 15 Schematic drawing of the formation of amyloid fibrils, (a) Monomeric insulin having an a-helical conformation, (b) [i-sheet (arrows) rich oligomers are being formed, (c) Amyloid fibrils having a diameter around 10 nm are being formed, (d) Higher magnification of the intrinsic repetitive (S-pIcatcd sheet structure of the amyloid fibril. The pictures were taken by transmission electron microscopy (TEM)...

Under the conditions of Example 5-23 the rubber phase of the end product shows an interesting micro-morphology. It consists of particles of 1-3 microns diameter into which polystyrene spheres with much lower diameters are dispersed. These included polystyrene spheres act as hard fillers and raise the elastic modulus of polybutadiene. As a consequence, HIPS with this micro-morphology has a higher impact resistance without loosing too much in stiffness and hardness. This special morphology can be visualized with transmission electron microscopy. A relevant TEM-picture obtained from a thin cut after straining with osmium tetroxide is shown in Sect. 2.3.4.14. 

Further characterization of the mechanical properties and structures of such zeolite-reinforced PDMS elastomers by Wen and Mark [139] also utilized small-angle neutron scattering (SANS) [141, 143, 214—220] and transmission electron microscopy (TEM). The neutron-scattering profiles of the pure and zeolite-filled PDMS networks were identical, which indicated negligible penetration of the polymer into the zeolite pores. The TEM pictures showed that the zeolite with the larger pore size had a somewhat smaller particle size, and this is probably the origin of its superior reinforcing properties [62, 139]. 

Most primary condensates are extremely small, ranging from 5 nm to 50 nm in diameter. Adequate characterization of such grains must rely on very high spatial resolution techniques such as transmission electron microscopy (TEM) or analytical electron microscopy (AEM). In the former technique, the emphasis is on obtaining very clear pictures of the morphology, homogeneity, elemental and mineralogical... 

Demonstier-Champagne et al. used atomic force microscopy (AFM) to observe microphase separation within cast films of PS-PMPS-PS/ PS-PMPS block copolymer mixtnre [43] that were nsed to compatibilize a blend of PMPS and PS. The fractnre snrface of blend films with the block copolymer incorporated show a far finer dispersion of particle sizes than those without. Matyjaszewski et al. studied PMPS-PS thin films by SFM (scanning force microscopy) and TEM (transmission electron microscopy) and Fig. 8 shows a TEM picture of a thin section of a film which was prepared by slow evaporation from THE, which is slightly selective for the polystyrene block [73]. 

These are very intimate mixtures composed of two or more sohd phases that differ in composition and each with particle sizes of 10 to 20 mn. Solid phases of these dimensions produce sols when dispersed in a liquid. Two or more sols of different composition can be uniformly mixed and gelled to obtain compositionally different nanocomposites. Figure 13.1a shows the transmission electron microscopy (TEM) picture of a sol-gel nanocomposite of mulhte composition consisting of spherical sihca particles (20 nm) and rod-like alumina (boehmite) particles (approximately 7 nm). Such a uniform physical mixture can be distinguished from a homogeneous sol-gel material which does not show any nonuniformity because it is mixed on an atomic scale (Figure 13.1b). The compositionally... 

Figure 4.25. High magnification image.s obtained by transmission electron microscopy of stained thin sections of a hyperbolic mesopha.se of a linear diblock copolymer, polystyrene-polyisoprene, whose morphology follows the D-surface (single node circled in middle picture) and possibly the gyroid. Staining produces high contrast between the two block domains. Note the very different magnifications.

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