Silver-lead system

Thus films can be divided into two groups according to their morphology. Discontinuous films are porous, have a low resistance and are formed at potentials close to the equilibrium potential of the corresponding electrode of the second kind. They often have substantial thickness (up to 1 mm). Films of this kind include halide films on copper, silver, lead and mercury, sulphate films on lead, iron and nickel oxide films on cadmium, zinc and magnesium, etc. Because of their low resistance and the reversible electrode reactions of their formation and dissolution, these films are often very important for electrode systems in storage batteries. 

The first descriptions of heteronuclear luminescent supramolecular complexes were given by Fackler et al. in 1988 and 1989. In these studies, one gold-thallium and one gold-lead complex were reported. As in the case of the gold-silver dinuclear systems, the extended systems appeared as a result of the unidirectional polymerization of dinuclear or trinuclear units through metal-metal interactions. These were prepared by reaction of the gold precursor [PPN][Au(MTP)2] (PPN = N(PPh3)2 ... 

Fluoride, chloride, bromide, and iodide derivatives of thallium(I) are well known. Their solubilities and photosensitivity are similar to the corresponding silver(I) systems. TIE is water-soluble, whereas the chlorides, bromides, and iodides are water-insoluble solids. This property is exploited in ligand-transfer chemistry involving thallium precursors. Some solid-state structures of thal-lium(I) salts of weakly coordinated anions show TT -halide interactions. Selective abstraction of a fluoride from a C-F bond, leading to thallium fluoride, has been described. The compound [ P(CH2CH2PPh2)3 RuH( 7 -ClTl)]PF6 represents the first metal complex containing an 77 -Cl-bonded TlCl ligand. This compound act as a thallium(I)-ion carrier. 

The equilibrium at each electrode is given by equation (9.3.9) for the silver silver chloride system. Reversible operation of this cell leads to a decrease in the KCl activity in the left-hand compartment and an increase in the right-hand one. At the same time there is transport of CP ions across the liquid junction from left to right, and transport of K" " ions in the opposite direction. The net cell reaction for exchange of one electron at each electrode is... 

Fio. 2. The concentrations of silver, lead, and copper in sediments of the Quinniptac River (Connecticut) system (previously unpublished Yale University data). Analyses made by emission spectrography. Concentrations in parts per million. 

Fig. 8.2 Characteristics of a typical lithium silver vanadium oxide battery. See text for details. (From Mehra R, Cybulski Z. Tachyarrhythmia termination lead systems and hardware design. In Singer I, ed. Implantable cardioverter defibrillator. Armonk, NY Futura Publishing, 1994 127, with permission.)...

Operating Temperature Limits. Like most other batteries, the performance of liquid-electrolyte reserve batteries is affected by temperature. Military applications frequently demand battery operations at all temperatures between -40 and 60°C, with storage limits of -55 to 70°C. These requirements are routinely met by the lead/fluoboric acid/lead dioxide systems and, with some difficulty at the low-temperature end, by the lithium/thionyl chloride and zinc/potassium hydroxide/silver oxide systems. Provision is occasionally made to warm the electrolyte prior to the activation of the two latter systems. 

Silver readily forms alloys with lead. Lead is often used as a base metal solvent for silver recovery processes. The lead—silver system is a simple eutectic having the eutectic point at 2.5 wt % silver and 304°C. The soHd solubihty of silver in lead is 0.10 wt % at 304°C, dropping to less than 0.02 wt % at 20°C. 

Fig. 1. Schematic representation of a battery system also known as an electrochemical transducer where the anode, also known as electron state 1, may be comprised of lithium, magnesium, zinc, cadmium, lead, or hydrogen, and the cathode, or electron state 11, depending on the composition of the anode, may be lead dioxide, manganese dioxide, nickel oxide, iron disulfide, oxygen, silver oxide, or iodine.

Thin films of photochromic glass containing silver haUde have been produced by simultaneous vacuum deposition of siUcon monoxide, lead siUcate, aluminum chloride, copper (I) chloride, and silver haUdes (9). Again, heat treatment (120°C for several hours) after vacuum deposition results in the formation of photochromic silver haUde crystaUites. Photochemical darkening and thermal fade rates are much slower than those of the standard dispersed systems. 

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