Gold decoration

Studies using gold decoration have been performed in several laboratories [345-349]. Thin solution cast films of nylon were studied by Spit 

Studies using gold decoration have been performed in several laboratories [282-286]. Thin solution cast films of nylon were studied by Spit [283], while Krueger and Yeh [284] studied stirred PE solutions which formed shish kebabs. Kojima and Magill [287] studied the morphology of spherulites of block copolymers by gold decorating sections. Shimamura [288] applied this method to the study of the internal structure of PE fibers. 

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Developments in electron microscopy also promise to revolutionize other studies of the surfaces of solids in general and/of catalysts in particular. Previously, monatomic steps and other topographical features at the exterior surfaces of solids were best investigated by the powerful but cumbersome, and destructive technique of gold-decoration - see refs 69 and 70 for studies of alkali halide and layered sulphides, respectively. 

Surface aggregation structure of the monolayer based on gold decoration technique... 

Bright field image after gold decoration... 

For insulating materials, on the contrary, the Fermi level lies in the gap, so that it is not detected on the photoelectron spectra. A possible calibration method stems from the gold decoration technique the binding energies can then be referred to the Au 4f doublet. This leads, however, to a poor reproducibility of the calibration Neither is the 1 s line of adventitious carbon a better energy standard. 

Silver and gold Decorating, mirrors, electrical contacts... 

Hardness measurements were made at 23 °C on 500 Angstroms gold-decorated epoxy square plates (2.50 cm by 2.50 cm, 2.00 mm thick) using a Leitz miniload micro-hardness tester, supplied by Ernst Leitz Company, Midland, Ontario, Canada. A load of 200 g was applied to the specimen. Experiments were done in accordance to ASTM D-785 and ASTM D-1706 test procedures. 

An even more refined method of study is interference-contrast microscopy [following Nomarski (767)] which converts minute topographical differences into color changes. Replica electron microscopy (77), gold decoration (see Section III,A,1), and scanning electron microscopy are also useful but less practicable. Occasionally it is profitable to follow the course of the reaction, in situ, using time-lapse cinematography (77). 

The surface topography of the partially oxidized specimens is examined, with low resolution, using interference-contrast microscopy and at high resolution by means of the gold-decoration technique 177, 180) in conjunction with transmission electron microscopy. 

Figure 3a. The y-globulin adsorbed on the sintered Teflon sample of Figure 2a (air-dry technique). Bovine Cohn II, lOOmg/dL, partial gold decoration. Key ...

Figure 4. Bovine y-globulin on sintered Teflon (3 mg/dL solution critical-point dried, partial gold decoration technique). Key bar equals 0.11xm.

Figure 5. Cohn I fibrinogen, 3 mg/dL, adsorbed on Teflon (partial gold decoration technique). Key a, air dried, sintered Teflon b, critical-point dried, sintered Teflon and c, critical-point dried, Fluorofilm Teflon. Bar equals 0.1 p,mfor b and c.

Partial gold decoration enhances the protein adsorbate image. Gold vapor atoms condense on the surface to be imaged and migrate until a stable... 

X-ray emission analysis of platinum-gold catalysts bears out that gold decorates the platinum particles rims pointing out that low coordination platinum atoms which are selectively deactivated by gold deposition, are responsible for the direct transformation of carvone into carvomenthone. 

Figure 1. Teflon, exposed to human albumin solution, 2500 mg/dl, for 1 hr at room temperature. Air drying and partial gold decoration TEM technique were employed. (Reproduced with permission from Ref. 4. Copyright 1977 American Society for Artificial Internal Organs.)...

B igure 3. Cohn I human fibrinogen, 3 mg/dl, adsorption on Teflon gold decoration TEM technique. (a) air dried (b) critical-point dried with bar equal to 0.1 ym. (Reproduced with permission from Ref. 5. Copyright 1982 American Chemical Society.)... 

Figure 4. Cohn I human fibrinogen, 30 mg/dl, adsorption on Teflon partial gold decoration TEM technique. Bar equal to 1000 A.

Figure 5. Effect of albumin preadsorption on fibrinogen adsorption. Air drying and partial gold decoration TEM were used for all samples. Key F, 30 mg/dl fibrinogen (Cohn I) and A F,...

K. MaUick, M.J. Witcomb, A. Dinsmore, and M.S. Scurrell, Polymerization of aniline by auric acid Formation of gold decorated polyaniline nanoballs, MacromoL Rapid Common., 26, 232 235 (2005). 

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