Rotating-copper-disk electrode techniques

Rotating-copper-disk electrode techniques have been used to evaluate the efficiency of the nickel macrocycle catalyst for the reduction of CO2 to Studies have been performed using Ni(diazacyclam) + (diazacyclam = 3,10-dimethyl-1,3,5,8,10,12-hexaazacyclophane) (5.6), a complex derived from cy-clam, which appears to be more active than [Ni(cyclam)2] " under the same conditions (see Figure 5.70) . These results are consistent with a mechanism proposed by other authors - . ... 

Shuman and Michael [10] applied a rotating disk electrode to the measurement of copper complex dissociation rate constants in marine coastal waters. An operational definition for labile and non-labile metal complexes was established on kinetic criteria. Samples collected off the mid-Atlantic coast of USA showed varying degrees of copper chelation. It is suggested that the technique should be useful for metal toxicity studies because of its ability to measure both equilibrium concentrations and kinetic availability of soluble metal. 

The successful determination of copper in beer, a complex system that precludes meaningful measurements under silent conditions, opened up the possibility for analysis in even more inaccessible media such as biological samples. Cavita-tional depassivation provides a remarkable enhancement in measured Faradaic currents whilst the increased mass transport due to acoustic streaming lowered the accumulation times below those required for other hydrodynamic voltammetric techniques such as rotating disk electrodes. 

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