Micrographs, electron

Gordon R., Bender R., Herman G.T. Algebraic reconstruction techniques (ART) for three-dimensional electron micrographs and X-ray photography., J. Theor. Biol., V. 29, 1970, p. 471-481. 

Fig. IV-18. (a) Electron micrograph of a collapsing film of 2-hydroxytetracosanoic acid. Scale bar 1. [From H. E. Ries, Jr., Nature, 281, 287 (1979).] (b) Possible collapse mechanism. [Reprinted with permission from H. E. Ries, Jr. and H. Swift, Langmuir, 3, 853 (1987) (Ref. 223). Copyright 1987, American Chemical Society.]...

Fig, XIV-12. Freeze-fracture transmission electron micrographs of a bicontinuous microemulsion consisting of 37.2% n-octane, 55.8% water, and the surfactant pentaethy-lene glycol dodecyl ether. In both cases 1 cm 2000 A (for purposes of microscopy, a system producing relatively coarse structures has been chosen), [(a) Courtesy of P. K. Vinson, W. G. Miller, L. E. Scriven, and H. T. Davis—see Ref. 110 (b) courtesy of R. Strey—see Ref. 111.]... 

Fig. XV-11. Electron micrograph of a freeze fracture replica of a region inside a mul-tivesicular liposome. Note the tetrahedral coordination nearly every vertex has three edges, and each face is connected to three others. The average number of edges per face is 5.1. (From Ref. 77.)...

Figure Bl.17.6. A protein complex (myosin SI decorated filamentous actin) embedded in a vitrified ice layer. Shown is a defociis series at (a) 580 mn, (b) 1130 mn, (c) 1700 mn and (d) 2600 mn underfocus. The pictures result from averagmg about 100 individual images from one electron micrograph the decorated filament length shown is 76.8 nm.

Figure C2.11.2. A scanning electron micrograph showing individual particles in a poly crystalline alumina powder.

Figure C2.11.3. A scanning electron micrograph of tire spherical alumina granules produced by spray drying a ceramic slurry. The granules are comprised of individual alumina particles, sintering additives, and an organic binder.

Figure C2.11.5. Scanning electron micrographs showing the microstmcture of an alumina ceramic spark-plug body (a) fracture surface and (b) polished and thennally etched cross section.

Figure C2.17.1. Transmission electron micrograph of a Ti02 (anatase) nanocrystal. The mottled and unstmctured background is an amorjihous carbon support film. The nanocrystal is centred in die middle of die image. This microscopy allows for die direct imaging of die crystal stmcture, as well as the overall nanocrystal shape. This titania nanocrystal was syndiesized using die nonhydrolytic niediod outlined in [79].

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 C2.17.3. Close-packed array of sub-micrometre silica nanoparticles. Wlren nanoparticles are very monodisperse, they will spontaneously arrange into hexagonal close-packed stmcture. This scanning electron micrograph shows an example of this for very monodisperse silica nanoparticles of -250 nm diameter, prepared in a thin-film fonnat following the teclmiques outlined in [236].

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.

Figure C2.17.5. Transmission electron micrograph of a field of anisotropic gold nanocrystals. In tliis example, a lower magnification image of gold nanocrystals reveals tlieir anisotropic shapes and faceted surfaces [36],...

Figure C2.17.6. Transmission electron micrograph and its Fourier transfonn for a TiC nanocrystal. High-resolution images of nanocrystals can be used to identify crystal stmctures. In tliis case, tire image of a nanocrystal of titanium carbide (right) was Fourier transfonned to produce tire pattern on tire left. From an analysis of tire spot geometry and spacing, one can detennine that tire nanocrystal is oriented witli its 11001 zone axis parallel to tire viewing direction [217].

Figure 1.1 is a rather remarkable photograph which shows individual polystyrene molecules as spherical blobs having average diameters of about 20 nm. The picture is an electron micrograph in which a 10" % solution of polystyrene was deposited on a suitable substrate, the solvent evaporated, and the contrast enhanced by shadow casting. There is a brief discussion of both electron microscopy and shadowing in Sec. 4.7. Several points should be noted in connection with Fig. 1.1 ...

Note that a statistical study could be done on an electron micrograph like that shown in Fig. 1.1. The dimensions of the blobs could be converted to volumes and then to masses with a knowledge of the density of the deposited polymer. This approach could be organized into a table of classified data from which any of these averages could be calculated. 

Figure 4.11 Electron micrographs of polyethylene crystals, (a) Dark-field illumination shows crystals to have a hollow pyramid structure. (Reprinted with permission from P. H. Geil, Polymer Single Crystals, Interscience, New York, 1963.) (b) Transmission micrograph in which contrast is enhanced by shadow casting [Reprinted with permission from D. H. Reneker and P. H. Geil, /. Appl. Phys. 31 1916 (I960).]...

Figures 4.1 la and b, respectively, are examples of dark-field and direct transmission electron micrographs of polyethylene crystals. The ability of dark-field imaging to distinguish between features of the object which differ in orientation is apparent in Fig. 4.11a. The effect of shadowing is evident in Fig. 4.11b, where those edges of the crystal which cast the shadows display sharper contrast.

The electron micrographs of Fig. 4.11 are more than mere examples of electron microscopy technique. They are the first occasion we have had to actually look at single crystals of polymers. Although there is a great deal to be learned from studies of single crystals by electron microscopy, we shall limit ourselves to just a few observations ... 

Fig. 4. Scanning electron micrograph of 5-p.m diameter Zn powder. Neck formation from localized melting is caused by high-velocity interparticle coUisions. Similar micrographs and elemental composition maps (by Auger electron spectroscopy) of mixed metal coUisions have also been made.

Fig. 10. Scanning electron micrograph of amorphous nanostmctured iron powder produced from the ultrasonic irradiation of Fe(CO). ...

Fig. 12. Scanning electron micrograph of sonochemicaUy synthesized hemoglobin microspheres.

Fig. 1. Transmission electron micrograph of ABS produced by an emulsion process. Staining of the mbber bonds with osmium tetroxide provides contrast...

Fig. 2. Transmission electron micrograph of ABS produced by a mass process. The mbber domains are typically larger in size and contain higher...

Fig. 2. RepHca electron micrograph of the fracture surface of enstatite—P-spodumene—zirconia glass-ceramic, showing twinning in the enstatite grains...

Fig. 3. Replica electron micrograph showing "house-of-cards" microstmcture in a machinable fluormica glass-ceramic (white bar = 10 fiva).

Fig. 8. Electron micrograph showing crystallization of icosahedral phase from glassy Pd—U—Si alloy.

Fig. 11. Scanning electron micrograph showing the intersection of primary shear bands with the glassy ribbon surface produced by simple bending.

Fig. 21. Transmission electron micrograph (tern) made from a cross-section of a metal-evaporated tape medium with the typical banana-like shape of...

Fig. 5. (a) Preparation method and (b) scanning electron micrograph of a typical expanded polypropylene film membrane, ia this case Celgard. 

Fig. 16. Scanning electron micrograph of a silicone mbber composite membrane.

Fig. 18. Cross-sectional scanning electron micrograph of a three-layered alumina membrane/support (pore sizes 0.2, 0.8, and 12 p.m, respectively).

Fig. 27. Scanning electron micrograph (a) and cross-sectional comparison (b) of screen and depth filters both having a nominal particulate cut-off of 0.4 flm. The screen filter (a Nuclepore radiation track membrane) captures particulates at the surface. The phase-inversion ceUulosic membrane traps the...

Iridium Oxide. Iridium dioxide [12030 9-8] coatings, typically used in combination with valve metal oxides, are quite similar in stmcture to those of mthenium dioxide coatings. X-ray diffraction shows the mtile crystal stmcture of the iridium dioxide scanning electron micrographs show the micro-cracked surface typical of these thermally prepared oxide coatings. 

Fig. 10. A dark field (DF) transmission electron micrograph showing interface in a continuous fiber (F) a-Al202 (F)/Mg alloy (ZE41A) matrix (M) within...

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

Fig. 17. Structuie of U-700 after piecipitation hardening temperature of 1168 C/4 h + 1079" C/4 h + 843 C/24 h + TGO C/IG h with air cooling from each temperature. A grain boundary with precipitated carbides is passing through the center of the electron micrograph. Matrix precipitates are y -Nij(TiAl).

---