Redox interaction between

In this reaction scheme, the steady-state concentration of peroxyl radicals will be a direa function of the concentration of the transition metal and lipid peroxide content of the LDL particle, and will increase as the reaction proceeds. Scheme 2.2 is a diagrammatic representation of the redox interactions between copper, lipid hydroperoxides and lipid in the presence of a chain-breaking antioxidant. For the sake of clarity, the reaction involving the regeneration of the oxidized form of copper (Reaction 2.9) has been omitted. The first step is the independent decomposition of the Upid hydroperoxide to form the peroxyl radical. This may be terminated by reaction with an antioxidant, AH, but the lipid peroxide formed will contribute to the peroxide pool. It is evident from this scheme that the efficacy of a chain-breaking antioxidant in this scheme will be highly dependent on the initial size of the peroxide pool. In the section describing the copper-dependent oxidation of LDL (Section 2.6.1), the implications of this idea will be pursued further. 

As shown earlier, A,A-dimethylaniline acts as an electron donor toward the electronically excited Ru(ll) tris(dipyridyl)complex (Bock et al. 1979). Nocera s group studied the effect of salt formation on the redox interaction between the ruthenium complex and the A/,At-dimethylaniline moiety. Two different salts, depicted in Scheme 5.26, were prepared and studied (Deng et al. 1997, Kirby et al. 1997, Roberts et al. 1997). 

Manganese. Photooxidation of Mn2+ upon flash excitation in an aqueous solution has been reported278. The redox interaction between Mn2+ and thionine278, in our opinion, is unlikely because Mn2+ is expected to be very short lived and the thionine concentration was very low. 

Cheraiti, N., Guezenec, S., Salmon, J. M. (2005) Redox interactions between Saccharomyces cerevisiae and Saccharomyces uvarum in mixed culture under enologjcal conditions. Applied... 

One factor that has greatly complicated elucidation of electron transfer in cytochrome oxidase is the strong redox interaction between the haems (see Refs. 12, 99). Although this phenomenon is relatively well elucidated, its functional relevance is not yet understood. 

The principal interest in salts of [Cr(bpy)3] + lies in their photochemical properties in particular the redox interactions between ground- and excited-state [Crfbpyls] with ground- and excited-state [Ruibpyla] are of great significance to photochemical systems (37,42,... 

Details of the coloration of glasses due to ligand field effects are further complicated by the possibility of redox interactions between two or more different transition metal ions. Other elements such as arsenic and antimony, which do not directly affect color, may alter the oxidation state of a coloring ion and alter the color of the glass. Changes in furnace atmosphere can also inadvertently alter the oxidation state of coloring ions due to changes in the concentrations of O2, CO, CO2, and H2O vapor. 

The redox interaction between transition metals and redox-active ligands is likely to permit a smooth reversible redox cycle in the transition metal-catalyzed oxidation reactions. Actually, the Wacker oxidation reaction of a terminal olefin proceeds catalytically only in the presence of a catalytic amount of polyaniline or polypyrrole derivative as a cocatalyst in acetonitrile-water under oxygen atmosphere to give 2-alkanone (Scheme Copper-free catalytic systems are... 

Reaction of main-group organometallic compounds with a metallic oxidant is considered to proceed via transmetaUation. Another reaction path lies in the redox interaction between them, affording the radical species (Scheme 2.57). These reactions are considered to provide a new route to reactive intermediates in oxidative transformations. 

Redox Interaction between Polyanilines and Transition Metals... 

To develop the redox catalyst system in water, a redox mediator is investigated using a water soluble polyaniline, poly(2-methoxyanilme-5-sulfonic acid) (PMAS). The redox interaction between PMAS (half ox) and V(1V) readily occurs to produce... 

At a therapeutic level, it is worth remembering that Zr is redox-inert and appears to play an inhibitory role in HzOz-mediated Ap toxicity by copper. After co-incubation of zinc with Cu(II), Zn(II) was found to rescue primary cortical and human embryonic kidney 293 cells that were exposed to Apl-42, correlating with the effect of Zn(II) in suppressing Cu(Il)-dependent HzOz formation from Abetal-42 [132]. Other antioxidants will also prove beneficial to counteract the toxicity of the redox interaction between Fe and Cu and Ap peptide. For example coenz)me coenzyme QIO is a well known nutraceutical that may serve this important antioxidant purpose for AD therapeutics [133]. 

Fig.6 shows the relationship between the Ce content and Pt dispersion. The maximum In the Pt dispersion curve corresponds perfectly with the minimum In the 50% CO conversion curve. It Is deduced that In the lwt% Pt-Ce0x-Ba0-A1203 system, 8wt% Ce content is the most suitable amount for promoting the redox Interaction between Pt and Ce and Inhibiting Pt sintering. 

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