Kinetics of reduction

Metal/environment interface—V ne cs of metal oxidation and dissolution, kinetics of reduction of species in solution nature and location of corrosion products him growth and him dissolution, etc. 

HU M and SKIBSTED L H (2002b) Kinetics of reduction of ferryhnyoglohin by (-)-epigallocatetechin gallate and green tea extract, J Agric Food Chem, 50, 2998-3003. 

The first column of Table III lists all possible 13C NMR distinguishable E-V triads whose central units are V. In the next column we present the same triad structures in binary notation (0=E, 1=V) with the central unit labeled as the site of (n-Bu)3SnH attack and the terminal units as either — (preceeding site) or -j- (following site). The final column presents the relative reactivities of the central V(l) unit in each triad toward (n-Bu)3SnH based on the kinetics of reduction determined for DCP and TCH. 

It has been believed that P-450 reduction by NADPH cytochrome P-450 reductase is a biphasic process, but it was recently shown [7] that some P-450 cytochromes are reduced with single-exponential kinetics and that the presence of substrate is not an obligatory condition for the reduction of all P-450 forms. Thus, the kinetics of reduction of various ferric P-450 cytochromes possibly depends on many factors such as substrate, rate-limiting step, etc. 

Miller and co-workers have recently prepared nanometer-scaled molecular dumbbells based on poly(benzyl ether) dendrons (G1-G4) and oligoimide spacers [64], Their synthetic approach involved the coupling of amine-terminated oligoimides to dendrons with a carboxylic acid focal point. The resulting hybrid materials were found to be quite soluble thus allowing their analysis by cyclic voltammetry in DMF. Consistent with Roncali s observation, the kinetics of reduction of the oligoimide core was not found to be limited by the presence of the dendritic wedges. 

Ashby and Yu have studied the kinetics of reduction of benzophenone with TIBA in ether and showed that the overall kinetic rate expression is second order, first order in TIBA and first order in ketone (151). The observed activation parameters were AG - 18.8 kcal/mol AH = 15.8 kcal/mol and AS = - 10.1 e.u. The negative entropy of activation is consistent with a cyclic transition state for the rate-determining hydride-transfer step. A Hammett study gave a value of p = 0.362, supporting nucleophilic attack by the aluminum alkyl on the carbonyl group in the rate-determining step. 

Larson O, Postma D (2001) Kinetics of reductive bulk dissolution of lepidocrocite, ferrihydrite, and goethite. 

The catalytic rate of hydrogenase adsorbed on the graphite electrode was measured by potential step chronoamperometry, in which cnrrent is monitored throughout a fixed sequence of potentials. This allows for direct observation of hydrogen oxidation activity at a particular potential over a period of time. Figures 5.14 and 5.15 show how chronoamperometry can be used to study the kinetics of reductive activation and oxidative inactivation respectively. A series of oxidative inactivation curves from several experiments like that shown in Fig. 5.14, showing the effect of pFl on oxidative inactivation, are shown in Fig. 5.15. The kinetics of the reactivation process can be... 

Fig. 16.3 (a) Kinetics of reduction of soluble Cr(VI) added concentrations of 1 jig g" Cr(VI) in various soils and (b) first-order plots of In [relative Cr(VI) concentration] versus time for the reduction of Cr(VI) in various soils. The slope of the lines is equal to the first-order rate constants for the case of 1 qg g Cr(VI) added. Reprinted with permission from Kozuh N, Stupar J, Gorenc B (2000) Reduction and oxidation processes of chromium in soils. Environ Sci Technol 34 112-119. Copyright 2000 American Chemical Society... 

Even a very weak interaction between A and B can have a dramatic effect on the kinetics of reduction. The calculated equilibrium and rate parameters for the reduction of AB as a function of/are shown in Table 1. A value off — 0.05 leads to an increase in the rate constant of about one order of magnitude. It is also seen that for / < 0.2 the stabilization energies of the complex are similar to the barrier for diffusional separation of the fragments, which occurs with a rate constant of about lO s . At room temperature and... 

The convolution analysis is based on the use of convolution data and further manipulation to obtain information on the ET mechanism, standard potentials, intrinsic barriers, and also to detect mechanism transitions. It is worth noting that the general outlines of the methodology were first introduced in the study of the kinetics of reduction of terf-nitrobutane in dipolar aprotic solvents, under conditions of chemical stability of the generated anion radical. For the study of concerted dissociative ET processes, linear scan voltammetry is the most useful electrochemical technique. 

Kinetics of Reduction of Toluidine Blue with Sulfite - Kinetic Salt Effect in Elucidation of Mechanism 244... 

Tratnyek PG, Miehr R, Bandstra JZ. Kinetics of reduction of TNT by iron metal. Groundwater Quality 2001 Third International Conference on Groundwater Quality, Sheffield, UK. IAHS Press, 2002 275 427 433. 

Choe S, Chang YY, Hwang KY, Khim J. Kinetics of reductive denitrification by nanoscale zero-valent iron. Chemosphere 2000 41 1307-1311. 

The kinetics of reductive dissolution reactions is made complicated (relative to the conceptual picture developed in Section 3.1) by electron transfer processes, similar to the way in which these processes bring complexity to... 

Mikulova et al. (2006) Raman Zr-Ce-Pr (Nd)-Ox Kinetics of reduction, effect of additives, lattice dynamics + + + CO oxidation storage mode of TWC... 

Solid-State Kinetics of Reduction and Reoxidation of M0O3 With Propene and 02... 

Z is reduced in the native system by electrons coming from the water-splitting enzyme and the kinetics of Z reduction are affected by the charge storage state (the so-called S states) of the enzyme. The differential kinetics of reduction for each S state were first observed by EPR [179] and correspond to the values obtained for the kinetics of S state turnover measured by absorption changes in the UV [180]. 

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