Silver diffusion

Fig. 14. Schematic cross section of Spectra integral film. The 600 Plus film has a similar stmcture. In these films the yellow image is formed by silver-assisted cleavage of a yellow dye releaser. A colorless developer reduces exposed silver hahde in the blue-sensitive emulsion in unexposed areas dissolved silver diffuses to the dye releaser layer and triggers the release of the yellow image dye.

The junction potentials for cells A and B can be assumed to be very similar in magnitude because their liquid junction potentials will be dominated by chloride ions diffusing out from the sinter at the bottom of the SCE (see Figure 3.4), rather than by silver diffusing into the SCE. Cell C has no sinter but a salt bridge. If we therefore consider cells A and B ... 

Because lire silver oxide electrode is slightly soluble in the potassium hydroxide electrolyte die separator is of a harrier type tu minimize silver diffusion lo die opposite electrode. 

Table II Copper and silver diffusion rates as a function of solder type...

The deposition of fission products on primary circuit surfaces and, in particular, on the reformer tube walls causes difficulties during maintenance and catalyst refilling procedures, if the activity is intolerably high. Cesium and silver isotopes released during reactor operation are of major concern. Particularly silver diffuses easily out of the fuel elements at operating temperature conditions into the coolant and migrates easily into metal surfaces and is difficult to remove in decontamination operations [32]. 

Case 1. Suppose we have diffusion of a solute across a sharp boundary at a = 0 from a solution into a solvent. The solute may be a salt dissolved in water it may be radioactive lead dissolved in lead diffusing into pure lead or it may be an ion in an ionic lattice diffusing into another lattice, e.g. silver diffusing from silver sulphide into copper sulphide, while copper passes in the opposite direction. For the equation (34) to hold we know that D must not be a function of C and that the amounts of solution and solvent must be great enough, the diffusion slow enough, or the time short enough, so that no appreciable amount of solute diffuses from the far extremity of the solution, or reaches the far extremity of the solvent (Fig. 1). In these systems, at = 0, (7 = Cq for x< 0, (7 = 0... 

Just as in the case of silver diffusing into gold, the concentration-voltage relations must be known prior to the experiment. 

Charge storage over long periods of time will result in loss by silver diffusion in the electrode. This phenomena is relevant for small charges stored over long times. A 13 loss after 30 h has been observed with AgBr (37) and about the same value after 12 days. 

Arzhannikov VA, Neuymin AD, Pal guyev SF, Fedin VV (1979) Silver diffusion on the solid oxides surface in an electric field. Elektrokhimiya (Rus) 15 1049-1051... 

Fig. 3. The ramified fractal nature of diffuse interfaces is shown for (top) a computer simulated 2-d monomer-monomer interface where the heavy region represents the connected monomers on one side, (middle) a simulated 2-d random coil polymer interface at the reptation time, and (bottom) electrochemically deposited Silver diffusing in polyimide with the unconnected metal atoms removed to show the fractal diffusion front of the connected metal atoms. (Wool and Long)...

Table 3. Silver diffusion coefficients DAg-10 , m /s in AgAu-alloys calculated for solid-phase and mixed kinetics for an ideally smooth and rough electrodes...

Very low values of the silver diffusion coefficient, typical for the selective dissolution of Agl5Au and Ag20Au alloys at 298 K, provide so small displacement of the diffusion front in the solid phase during obtaining the potentiodynamic dependencies that this front repeats in fact the electrode surface microrelief Therefore, the voltammetric peak current is directly proportional to the roughness factor. 

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