Incorporating silver ions into

Under the chosen conditions aromatic compounds are nitrated to nitroaromatics [1]. The detection of rotenone [1] (see below) depends on the reduction of silver ions, incorporated into the layer, to metallic silver in the presence of ammonia [4]. The mechanism of the reaction of many substances leading to fluorescent derivatives has not yet been elucidated [2],... 

Figure 4.12 A solid-state electrode showing a second-order response. The electrode shown in Figure 4.11 can be modified by the incorporation of silver chloride into the membrane to enable the activity of chloride ions in a sample to be measured. A surface reaction between the test chloride ions and the membrane silver ions alters the activity of the latter, resulting in a change in the potential difference across the membrane.

Research into controlled-release antimicrobials continues with organo-silver compounds and silver zeolites, which are promising candidates for textile finishes. Silver ions, for example, incorporated in glass ceramic, have a very low toxicity profile and excellent heat stability. These principles are also used for fibre modification, an alternative to the antimicrobial finishes with high permanence. In recent years a variety of antimicrobial modified fibres have been developed, including polyester, nylon, polypropylene and acrylic types. An example of these fibre modifications is the incorporation of 0.5-2 % of organic nitro compounds... 

BFr< SbFg. This order parallels that observed for olefin solubility in concentrated silver salt solutions (40, 193). Structural investigations of crystalline silver-olefin complexes have shown a nearly covalent bond between the silver and the nitrate ions (28, 399), but an electrostatic bond only between silver and fluoroborate ions (537). Consequently, the differing complex stability may be largely attributable to the differences in the energy required for the expansion which permits incorporation of the olefin molecule into the salt lattice. These differences will depend upon the anion composition (537), geometry, and size. Similarly, the degree of silver ion-anion association in concentrated solutions will vary with the anion and a similar explanation can account for the dependence of olefin solubility on the anion. In dilute solutions, however, the silver ion environment and thus the olefin solubility may be essentially independent of the anion (193). 

The impregnation of the layer with silver ions is performed by either incorporating the silver salt into the silica gel slurry or by immersing or spraying the plate with water, ethanol, methanol, ammonia, or acetonitrile solutions of the salt. Silver nitrate is normally used. The only method that affords proper control of the Ag(I) content in the layer is to add silver nitrate to the slurry. However, this... 

The use of a pair of identical metallic electrodes to establish the equivalence point in amperometric titrations offers the advantages of simplicity of equipment and elimination of the need to prepare and maintain a reference electrode. This type of system has been incorporated into equipment designed for the routine automatic determination of a single species, usually with a coulometric generated reagent. An example of this type of system is an instrument for the automatic determination of chloride in samples of serum, sweat, tissue extracts, pesticides, and food products. Here, the reagent is silver ion coulometrically generated from a silver anode. The indicator system consists of a pair of twin silver electrodes that are maintained at a potential of perhaps 0.1 V. Before the equivalence point in the titration of chloride ion, there is essentially no current because no easily reduced species is present in the solution. Consequently, electron transfer at the cathode is precluded and that... 

A final method of enhancing resolution is to incorporate into the stationary phase a species that complexes or otherwise interacts with one or more components of the sample. A well-known example of the use of this option occurs when an adsorbent impregnated with a silver salt is used to improve the separation of olefins. The improvement is a consequence of the formation of complexes between the silver ions and unsaturated organic compounds. 

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