Extended anode

Recommended Extended anode installation Mostly used for Aggressive soils and Soils Deep C/i... 

For extended anodes or strip grounds, 4t / so that the formula in line 9 in Table 24-1 becomes ... 

Less important oxides are Ag203, obtained impure by extended anodic oxidation of silver, and Ag30, obtained hydrothermally from Ag/AgO at 80°C, 4000 bar, which is a metallic conductor with the anti-BiI3 structure containing an hep array of silvers with oxide ions occupying 2/3 of the octahedral holes [32]. 

The limited anodic potential range of mercury electrodes has precluded their utility for monitoring oxidizable compounds. Accordingly, solid electrodes with extended anodic potential windows have attracted considerable analytical interest. Of the many different solid materials that can be used as working electrodes, the most often used are carbon, platinum, and gold. Silver, nickel, and copper can also be used for specific applications. A monograph by Adams (17) is highly recommended for a detailed description of solid-electrode electrochemistry. 

Equation 16.9 tells us that the protective oxide film on iron will be preserved in alkaline media, weakened in neutral water, and lost in acidic environments. Indeed, in very acidic solutions, the distinction between extended anodic and cathodic sites will be lost along with the oxide film, although local anodic and cathodic spots will persist, and so dissolution of iron with accompanying hydrogen evolution becomes general across the surface of the specimen. 

Lead-dioxide-coated electrodes are accessible by the sol-gel method described by Avaca, using Pb(acac)2 (23a) and a mixture of ethanol and acetic acid as starting materials. The solution was spread on a boron-doped diamond electrode body and heated at 400 °C for 1 h in argon atmosphere. Pb02 electrodes have been widely used as anodes under extreme conditions, due to their extended anodic window in aqueous media. ... 

It will be apparent from Table 3 that, apart from the use of tetrafluoroborates and hexafluorophosphates, extended anodic limits can be obtained at low temperatures [212] or by the use of acidic solvents such as CF3COOH [81,211,216], FSO3H [186,217-221], HF [222], and CF3SO3H (without supporting electrolyte) [213]. In addition to the electrolyte systems included in the tables, hydrocarbon oxidation has been realized in nitromethane. 

Fig 12 is a conceptual sketch of what a CT expls detection system might look like. The objects to be examined are placed on a conveyor belt, 2 to 3 meters long, which passes between an X-ray source on one side and an array of column detectors on the other. The design speed for the conveyor is 30cm/sec. The column detectors are 60cm hi with vertical slit collimators focused on the extended-anode X-ray source. Source and detector collimation will vary depending on the distance from the source to the detector, so that the spatial dispersion of the X-ray pencil beams thru the examined olqect will be the same for ail projection angles... 

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