Rate constants for reductive

With this assumption, the rate constants for reductive removal ofan ethyl, an isopropyl, and a teii-butyl group can be estimated as follows ... 

Under aqueous conditions, flavonoids and their glycosides will also reduce oxidants other than peroxyl radicals and may have a role in protecting membranal systems against pro-oxidants such as metal ions and activated oxygen species in the aqueous phase. Rate constants for reduction of superoxide anion show flavonoids to be more efficient than the water-soluble vitamin E analogue trolox (Jovanovic et al, 1994), see Table 16.1. 

Studies of medium effects on hexacyanoferrate(II) reductions have included those of dioxygen,iodate, peroxodisulfate, - [Co(NH3)5(DMSO)] +, and [Co(en)2Br2]+. Rate constants for reaction with dioxygen depended strongly on the electron-donor properties of the organic cosolvent. Rate constants for reduction of peroxodisulfate in several binary aqueous media were analyzed into their ion association and subsequent electron transfer components. Rate constants for reduction of [Co(en)2Br2] in methanol water and dioxan water mixtures were analyzed by a variety of correlatory equations (dielectric constant Grunwald-Winstein Swain Kamlet-Taft). 

Table II, Rate Constants for Reduction of Surface-Ferricenium by Various Reductants at 298 K.

Neta P, Eluie RE, Mosseri S, Shastri LV, Mittal JP, Maruthamuthu P, Steenken S (1989) Rate constants for reduction of substituted methylperoxyl radicals by ascorbate ions and N,N,N, Al -tetrameth-yl-p-phenylenediamine. J Phys Chem 93 4099-4104 Netto LES, Stadtman ER (1996) The iron-catalyzed oxidation of dithiothreitol is a biphasic process hyudrogen peroxide is involved in the initiation of a free-radical chain of reactions. Arch Biochem Biophys 333 233-242... 

The rate constant for reduction of primary alkyl radicals with Sml2 has been determined using a radical clock (see Section 10.6) providing further information for understanding the mechanism [22]. The commonly used 5-hexenyl radical clock, where the rate constant for cyclisation is known (kc = 2.3 x 105 s-1 at 20°C), was used to determine the rate constant... 

In the following discussion, it is assumed that the expression of the rate constants for reduction and oxidation processes is given by the Butler-Volmer formalist ... 

Selected Rate Constants for Reductions of Environmental Contaminants. 

Additional work by the Forster group, making use of transient emission spectroscopy, probed the rate of photoinduced electron transfer between metal centers within a novel trimeric complex [Os(II)(bpy)2(bpe)2 ] [Os(II) (bpy)2Cl]2 4+, where bpy is 2,2/-bipyridyl and bpe is fra s-l,2-bis-(4-pyridyl) ethylene. Transient emission experiments on the trimer, and on [Os(bpy)2(bpe)2]2+ in which the [Os(bpy)2Cl]+ quenching moieties are absent, reveal that the rate of photoinduced electron transfer (PET) across the bpe bridge is 1.3 0.1 x 108s-1. The electron transfer is believed to be from the peripheral Os(II)Cl metal centers to the [Os(bpy)2(bpe)2]2+ chro-mophore. Comparison to rate constants for reduction of monolayers at a Pt electrode reveals that the photoinduced process is significantly faster [39]. 

First-order rate constant for reduction of Chromium(VI) to Chromium(lll) in the red cell (day 1)... 

Table I. Comparisons of Rate Constants for Reduction of Disulfide Bonds in Proteins Using Dithiol Reagents (DTT, BMS, DMH) ...

Table 22 Rate Constants for Reductive Coupling of A -Substituted Pyridinium, Quinolinium, and Acridinium Compounds...

Figure 3. Dependence of pseudo-first order rate constant for reduction of OFeP TDCSPP by Acid Orange 12 on [Dye], pH 6.93 p = 0.05 mol dm 30 C...

If the substrate is an insulator, Js = 0. If both tip and substrate reactions are electrochemical processes, the rate constants for reduction (kf) and oxidation (kb) are given by the Butler-Volmer relations ... 

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