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reactions with the OH radical. Here we report room temperature rate constants for the reaction of OH with ELA ( 1 ). Our work is part of a comprehensive experimental and theoretical study on the kinetics and photochemistry of 2G biofuels: the first

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Abstract  

On the basis of results of kinetic investigates of many compounds general temperature dependence of Gibbs free energy of activated complexes created in thermal decomposition processes and the reaction rate constant were calculated.

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Abstract  

Light emission during the dissolving of irradiated sugars (lyoluminescence, LL) allows the estimation of absorbed dose. The use of 1-mannose as LL substance and the correlation between the concentration of paramagnetic centres and LL yield in the presence of [Fe(CN)6]4− and CNS anions demonstrated the possibility to measure relative rate constants of the reaction of mannose peroxy-radicals with different substances soluble in water.

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We have analyzed the dependence of the thermal electron capture rate constant on molecular parameters as dipole moment, electronic and orientational polarizabilities. We have found that there is a linear dependence between the logarithm of the rate constant and the electronic polarizability on the electron-accepting center.

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Journal of Thermal Analysis and Calorimetry
Authors: Lisardo Núñez, F. Fraga López, L. Fraga Grueiro, and J. A. Rodriguez Añón

From the peak reaction temperatures as a function of heating rate, the activation energies were obtained for a system consisting of an epoxy resin (Badgen=0) and a curing agent (isophorone diamine), using a Perkin Elmer DSC7 operated in the dynamic mode. At the same time, the Arrhenius law was used to calculate rate constants.

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The kinetics of reaction of indium(III)ion with EDTA (H4 edta) has been studied in aqueous acidic solutions using carrier-free111In and low concentrations of EDTA. The reaction takes place predominatly between indium(III) and H3 edta. The rate constant k3 is determined to be k3=(1.3±0.1)·105 dm3 mol–1 s–1 (25 °C).

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The mechanism of the reduction reaction of lanthanide(III) ions by hydrated electrons in polar solvents has been investigated. The theoretical rate constants for the reaction of hydrated electrons with a number of lanthanide ions have been calculated using the energy gap laws of the charge shift reaction(D+−A→D−A+) and compared with experimental values. With these results, we have explained the large difference of the reaction rates of lanthanide ions with hydrated electrons, which depend upon the kind of lanthanide ion. The calculated results agree almost quantitatively with the experimental values.

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Radiation induced decomposition of solid alkali metal nitrates at room temperature has been studied up to an absorbed dose of 300 kGy. [NO 2 ] increases with absorbed dose. From the kinetic scheme
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$NO_3^ - \xrightarrow{{{}^k1}}NO_2^ - + 0; O + NO_2^ - \xrightarrow{{{}^k2}}NO_3^ - ;$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$O + NO_3^ - \xrightarrow{{{}^k3}}NO_2^ - + O_2$$ \end{document}
, rate constants have been evaluated for the overall radiolytic decomposition of alkali metal nitrates. This kinetic scheme is applicable in the low dose range. At higher doses, however, the radiation induced reaction, NO 2 +1/2 O2 NO 3 may also contribute. The overall rate constants are 0.13×10–6 (LiNO3), 1.05×10–6 (NaNO3), 10.10×10–6 (KNO3), 9.50×10–6 (RbNO3) and 25.50×10–6 (CsNO3) kGy–1.
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Determination of power-time curves of bacterial growth

Study of lowest growth temperature

Journal of Thermal Analysis and Calorimetry
Authors: Sun Haitao, Nan Zhaodong, Liu Yongjun, Zhang Honglin, and Zhang Tonglei

Bacterial growth power-time curves were determined with a 2277 Thermal Activity Monitor. Bacterial multiplication curves were measured at different temperatures and an experimental model was established. Both growth rate constants and lowest growth temperatures were calculated.

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Abstract  

Translational diffusion of poly-2,5-(1,3-phenylene)-1,3,4-oxadiazole (PMOD) in solution in 96% sulphuric acid was studied, and intrinsic viscosity was measured at different stages of thermal degradation. Polymer solution has previously been subjected to heating at temperature ranging from 75 to 104C and then investigated at 26C. A monotonic decrease in intrinsic viscosity and the molecular mass, M, of degraded products with increasing degradation temperature was detected. The rate constant of the degradation process has been obtained from the change in M of the degradation products with time at a fixed solution temperature, and the activation energy of the process was calculated by using the temperature dependence of the rate constant. The activation energy (E =1028 kJ–1 ) is close to that obtained previously for the hydrolysis of poly-2,5-(1,4-phenylene)-1,3,4-oxadiazole (PPOD) in sulphuric acid (106 kJ–1 ), the rate constant being approximately twice in the value.

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