Oxide reduction behavior

Recent work has resolved some of the issues that complicate direct electrochemistry of myoglobin, and, in fact, it has been demonstrated that Mb can interact effectively with a suitable electrode surface (103-113). This achievement has permitted the investigation of more complex aspects of Mb oxidation-reduction behavior (e.g., 106). In general, it appears that the primary difficulty in performing direct electrochemistry of myoglobin results from the change in coordination number that accompanies conversion of metMb (six-coordinate) to reduced (deoxy) Mb (five-coordinate) and the concomitant dissociation of the water molecule (or hydroxide at alkaline pH) that provides the distal ligand to the heme iron of metMb. 

Shimada, H., and Orii, Y. (1976). Oxidation-reduction behavior of the heme c and heme d moieties of Pseudomonas aeruginosa nitrite reductase and the formation of an oxygenated intermediate at heme d. J. Biochem. (Tokyo) 80, 135-140. 

Krikorian, S.E. 1988. Methodology for quantifying functional group oxidation state levels and for analyzing organic reactions for oxidation-reduction behavior. Am. J. Pharm. Educ. 52, 177-180. 

The oxidation-reduction behaviors of neptunium, plutonium and americium in basic solution have been determined via polarographic and coulometric studies (6-9). These studies, which showed that the more soluble (V), (VI), and (VII) oxidation states of these actinides are stable in alkaline solution under certain redox conditions, helped identify possible actinide species and oxidation states in our experiments. Actual identification of radioelement oxidation states was not done in the present experiments. 

K) -1690 10 kJ mol 1. The preparation and properties of this and other actinide (IV) complex oxides are described and are compared with other perovskites BaM03. The relative stabilities of tetravalent and hexavalent uranium in various environments are compared in terms of the oxidation-reduction behavior of uranium in geological nuclear waste storage media in perovskite, uranium(IV) is very unstable in comparison with uranium(VI). ... 

The oxidation-reduction behavior, ascertained by direct current (conventional) polarography, and its dependence on pH in aqueous solution of the [P2Mo18062] 6, [As2Moi8062]-6, and [P2Wi8062]-6 anions may be found in Refs.1S9 161>. The polarographic behavior of the dimeric 9-molybdophosphate anion of (NH4)6 [P2Moi 8062] was examined by cyclic voltammetry and alternating current... 

A considerable amount of literature has appeared which describes the use of heteropolymolybdates and their tungsten analogs in various applications. Of these, the main applications have centered on catalysis. Of particular importance to the catalytic behavior of heteropoly compounds is the solubility and solvolytic behavior in both aqueous and organic media and the thermal stability and oxidation-reduction behavior. 

Additional information on the oxidation-reduction behavior of berkelium can be found in a comprehensive review (238). 

The oxidation-reduction behavior of plutonium is described by the redox potentials shown in Table I. (For the purposes of this paper, the unstable and environmentally unimportant heptavalent oxidation state will be ignored.) These values are of a high degree of accuracy, but are valid only for the media in which they are measured. In more strongly complexing media, the potentials will change. In weakly complexing media such as 1 M HClOq, all of the couples have potentials very nearly the same as a result, ionic plutonium in such solutions tends to disproportionate. Plutonium is unique in its ability to exist in all four oxidation states simultaneously in the same solution. Its behavior is in contrast to that of uranium, which is commonly present in aqueous media as the uranyl(VI) ion, and the transplutonium actinide elements, which normally occur in solution as trlvalent... 

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