Dark shadow image

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.

Fig. 1. X-rays or gamma rays are used to create a shadow image of light and dark that reveals any flaw s or inclusions in a test pad...

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... 

Fig. 14 (a) Shadowed sample of dispersed resin G. The insets are dark-field images. Low-intensity bright-field diffraction contrast images of (b) TE-30 (bottom) and (c) TE-3698 (top), and TE-3170 (bottom). The upper part of b (d) has Pt/C-shadowed TE-30 particles the insets in c are enlargements of some of the particles. All scale bars in a given figure part represent the same scale unless otherwise identified. 

As we chanted our invocation, the space around and through us changed to deep dark underworld images and the serpentine power of the kundalini. The rocks took on hues of orange and purple and a reptilian consciousness that caused them to shift and undulate. I spoke aloud Shadow, be my friend. ... 

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. 

Dark field Visualization technique for ashes produced by microincineration and fluorescence microscopy useful for low-contrast subjects Electron systems imaging EM shadowing Detection, localization, and quantitation of light elements Structural information from ordered arrays of macromolecules... 

Fig. 12. Diagrammatic sketch of B6nard s direct-shadow system for locating the cell centers and cell partitions on the surface of the liquid. With the viewing screen at Pi, the cell centers appeared to be bright spots, A, B, and C on a dark background, whereas, when the screen was moved closer to the liquid, as at P2, the image became one of dark lines on a bright background. B nard s apparatus was actually somewhat different than shown, but the diagram illustrates its important features.

Although many studies on DNA and DNA-protein interaction have utilized metal shadowing to produce bright-held image contrast, dark-held TEM (annular or spectroscopic) of unstained or uranyl acetate-stained and metal-shadowed nucleic acid-protein complexes also provides useful resolution. In Figure 5, a short length of DNA (2356 base pairs), with attached progesterone receptor, is revealed by dark-held TEM. The RecA protein has the ability to... 

The light buff colors associate with the marine waters but are also found in the mountains where shadows are evident in the individual band and color composite images. Red occurs where there is some heavy vegetation. Dark olive is found almost exclusively in the ocean against the beach. The orange, green, and blue colors have less discrete associations. 

Fig. 13.4a,b. Normal (arrow) and stool-impacted diverticulum (arrowhead). VE shows complete dark ring at the normal diverticulum and incomplete ring shadowing at the impacted diverticulum simulating a polypoid lesion. On 2D images in the impacted diverticulum, a hyperdense ring with a hypodense center can be found... 

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