Results 301 to 310 of about 1,922,304 (342)

Absolute Rate Constants for Iminyl Radical Reactions

The Journal of Organic Chemistry, 1997
The kinetics of cyclization of the 2-methyl-6,6-diphenyl-5-hexeniminyl radical (3) were measured by laser flash photolysis methods from 0 to 50 degrees C, and the kinetics of trapping of radical 3 by thiophenol and p-chlorothiophenol were determined between 4 and 83 degrees C by indirect methods using the unimolecular rate constants as the basis values.
Marie-Helene, Le Tadic-Biadatti, Anne-Claude, Callier-Dublanchet, John H., Horner, Béatrice, Quiclet-Sire, Samir Z., Zard, Martin, Newcomb   +5 more
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Rate constants for aminyl radical reactions

Tetrahedron Letters, 1993
Abstract Rate constants for cyclization of the N -methyl-5,5-diphenyl-4-pentenaminyl radical ( 4 ) and for reaction of this radical with t -BuSH were determined by direct methods.
Martin Newcomb, John H. Horner, Haifa Shahin   +2 more
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Absolute Rate Constants for α-Amide Radical Reactions

The Journal of Organic Chemistry, 1998
The 1-(diethylcarbamoyl)-6,6-diphenyl-5-hexenyl radical (4a), the 1-(diethylcarbamoyl)-7,7-diphenyl-6-heptenyl radical (4b), and the 1-(diethylcarbamoyl)-1-methyl-6,6-diphenyl-5-hexenyl radical (4c) were produced from the corresponding PTOC esters (anhydrides of the carboxylic acid and N-hydroxypyridine-2-thione) by laser flash photolysis methods.
Osama M., Musa, Seung-Yong, Choi, John H., Horner, Martin, Newcomb   +3 more
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Determination of Rate Constants for Rapid Peroxidase Reactions

Analytical Biochemistry, 1995
We describe an improved enzyme-monitored stopped-flow method for determining rate constants for peroxidase reactions that are too rapid to measure by conventional pseudo-first-order methods. Ascorbate will reduce many substrate radicals as rapidly as they are generated by a peroxidase.
D C, Goodwin, I, Yamazaki, S D, Aust, T A, Grover   +3 more
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Calculating Rate Constants in Forward Drug Transfer Reactions

Journal of Pharmaceutical Sciences, 1973
A simple method for obtaining and processing drug transfer data derived from in vitro model cells such as the Schulman cell is presented. Simplified calculation procedures are developed for determining the rate constants that describe the transfer of the drug through the compartments. Transfer of the acidic drug salicylic acid from a pH 2.0 compartment
W O, Thompson, S T, Christian
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The Reaction Rate Constant of Chlorine Nitrate Hydrolysis

Chemistry, 2001
The first-order rate constant for the decomposition of chlorine nitrate (ClONO2) by water in a cyclic 1:3 complex at stratospheric temperatures is shown to be close to the values for the hydrolysis rate coefficient of chlorine nitrate on an ice surface determined in the laboratory.
T, Loerting, K R, Liedl
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Quantum mechanical rate constants for bimolecular reactions

The Journal of Chemical Physics, 1983
Several formally exact expressions for quantum mechanical rate constants (i.e., bimolecular reactive cross sections suitably averaged and summed over initial and final states) are derived and their relation to one another analyzed. It is suggested that they may provide a useful means for calculating quantum mechanical rate constants accurately without ...
William H. Miller, Steven D. Schwartz, John W. Tromp   +2 more
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Calculations of parabolic reaction rate constants

Oxidation of Metals, 1987
The oxidation kinetics of only a very limited number of pure metals or binary alloys can be described by the simplest parabolic law, Δm2=kpt, Thus for a transient period of faster kinetics, the steady state parabolic law is given by (Δm−Δmi)2 = kp(t−ti) when the initial weight gain Δmi does not contribute to steady state rate control. In such a case, a
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Determination the rate constants of some biexponential reactions

Journal of Biochemical and Biophysical Methods, 2000
Reactions that are described by biexponential functions are typical for many biological processes. The kinetics of these reactions is described by transcendental irrational equations interconnecting the reagent concentrations, time and rate constants.
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Improved Calculation of Quasiequilibrium Reaction Rate Constants

The Journal of Chemical Physics, 1963
The method of steepest descents has been applied to the calculation of the total number of quantum states of a system of harmonic oscillators. The corresponding rate expressions of unimolecular reactions have also been derived.
S. H. Lin, Henry Eyring
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