Silver spots

Adults are gray moths with a silver spot in the middle of each forewing. They emerge from overwintering pupae in May and lay light green, dome-shaped eggs on the undersides of leaves. 

Figure 10.14. Scheme 1 depicts the formation of the three-component sandwich assay discussed in the text. (a) and (b) show flatbed scanner images of microarrays treated with gold nanoparticles before and after silver enhancement, respectively, (c) shows a typical Raman spectrum acquired from one of the silver spots. (d) shows a profile of the Raman intensity at 1192 cm-1 as a function of position on the chip the laser beam from the Raman instrument is moved over the chip from left to right as defined by the line in (b). (With permission from Ref. 40.)... 

Description Adults gray moths with a silver spot iff the middle of each forewing I 1 /2 -2 wihgspan). Larvae green, IV2 caterpillars with 2 white lines down their backs,... 

Figure 31. Image of silver spots, produced by laser deposition, using transmitted light illumination. The diameter of a spot is typically 50 mm. The irradiance was 560 W/cm with a 40X, NA 1.2 objective. Images (A-F ) were taken 5 s apart. Adapted from reference 48.

Figure 33. Light-deposited silver produced electroehemically. Constant current circuit (Top), absorbance spectrum of silver spot on glass (Bottom).

The Model 412 PWR uses several control mechanisms. The first is the control cluster, consisting of a set of 25 hafnium metal rods coimected by a spider and inserted in the vacant spaces of 53 of the fuel assembhes (see Fig. 6). The clusters can be moved up and down, or released to shut down the reactor quickly. The rods are also used to (/) provide positive reactivity for the startup of the reactor from cold conditions, (2) make adjustments in power that fit the load demand on the system, (J) help shape the core power distribution to assure favorable fuel consumption and avoid hot spots on fuel cladding, and (4) compensate for the production and consumption of the strongly neutron-absorbing fission product xenon-135. Other PWRs use an alloy of cadmium, indium, and silver, all strong neutron absorbers, as control material. 

Qualitative. The classic method for the quaUtative determination of silver ia solution is precipitation as silver chloride with dilute nitric acid and chloride ion. The silver chloride can be differentiated from lead or mercurous chlorides, which also may precipitate, by the fact that lead chloride is soluble ia hot water but not ia ammonium hydroxide, whereas mercurous chloride turns black ia ammonium hydroxide. Silver chloride dissolves ia ammonium hydroxide because of the formation of soluble silver—ammonia complexes. A number of selective spot tests (24) iaclude reactions with /)-dimethy1amino-henz1idenerhodanine, ceric ammonium nitrate, or bromopyrogaHol red [16574-43-9]. Silver is detected by x-ray fluorescence and arc-emission spectrometry. Two sensitive arc-emission lines for silver occur at 328.1 and 338.3 nm. 

Coffey, C.S., Hot Spot Production by Moving Dislocations in a Rapidly Deforming Crystalline Explosive, in Eighth Symposium (International) on Detonation, NSWC MP 86-194 (edited by Short, J.M.), Naval Surface Weapons Center, White Oak, Silver Spring, MD, 1986, pp. 62-67. 

Figure 5.19 MALDI-ToF mass spectrum, providing a molecular-weight profile of the tryptic peptides derived from spot 22 (see Figure 5.18) of the silver-stained two-dimensional gel of the proteins extracted from the yeast S. cerevisiae. From Poutanen, M., Salusjarvi, L., Ruohonen, L., Penttila, M. and KaUddnen, N., Rapid Commun. Mass Spectrom., 15, 1685-1692, copyright 2001. John Wiley Sons Limited. Reproduced with permission.

GP 4] [R 5] For an undisclosed methanol derivative, no hot spot (close to 0 K rise) was found for the construction-material silver micro reactor (operational temperature 390 °C) hot spots of 160 and 60 K were found for laboratory pan-like (40% 50% 550 °C) and short sheU-and-tube reactors, respectively, using elemental silver [1,49-51, 108]. 

Stability of the silvering with respect to peel-off is increased, and spots are less likely. 

Since SERS and SERRS are substance specific, they are ideal for characterisation and identification of chromatographically separated compounds. SE(R)R is not, unfortunately, as generally applicable as MS or FUR, because the method requires silver sol adsorption, which is strongly analyte-dependent. SE(R)R should, moreover, be considered as a qualitative rather than a quantitative technique, because the absolute activity of the silver sol is batch dependent and the signal intensity within a TLC spot is inhomogeneously distributed. TLC-FTIR and TLC-RS are considered to be more generally applicable methods, but much less sensitive than TLC-FT-SERS FT-Raman offers p,m resolution levels, as compared to about 10p,m for FTIR. TLC-Raman has been reviewed [721],... 

Spanakis, E., Lamina, P, and Bennett, D. C. (1992). Effects of the developmental colour mutations silver and recessive spotting on proliferation of diploid and immortal mouse melanocytes in culture. Development 114 675-680. 

Neukirchen et al. (1982) from the Max-Planck Institute employed a similar miniaturized IEF/SDS-PAGE system that was roughly 2 cm x 2 cm. Silver staining was used to detect spots containing as little as 10 pg of protein, and electrophoresis was used to separate the proteins contained within a single Drosophila egg. 

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