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Abstract  

It has been demonstrated that a single plot of the values of Δlnα1/2/Δln(1-α) (taken from a single α−T curve obtained under a controlled linear increase of the reaction rate) as a function of the corresponding values of Δ(1/T)/Δln(1−α) permits the simultaneous determination of both the activation energy and the kinetic model in accordance with a solid state reaction.

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The errors in the activation energies of solid-state reactions determined with the Piloyan method are more larger than those previously assumed in the literature. On the other hand, the errors in the kinetic parameters are strongly dependent on the kinetic law obeyed by the reaction. A theoretical explanation of this behaviour is given.

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Kinetic investigation on thermal decomposition of organophosphorous compounds

N,N-dimethyl-N′,N′-diphenylphosphorodihydrazidic and diphenyl amidophosphate

Journal of Thermal Analysis and Calorimetry
Authors:
M. Sovizi
and
K. Anbaz

the activation energy ( E ) and the pre-exponential factor ( A ) for both the compounds studied. These methods are as follows: Kissinger equation [ 20 ]: (1) where & is heating rate, T m is the

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Journal of Thermal Analysis and Calorimetry
Authors:
S. M. Sidel
,
F. A. Santos
,
V. O. Gordo
,
E. Idalgo
,
A. A. Monteiro
,
J. C. S. Moraes
, and
K. Yukimitu

crystallization kinetic of the Li 2 O–TeO 2 –WO 3 glass system determining the activation energy and the Avrami exponent from the formed crystalline phases due to heating treatment of the samples. Materials and methods The glasses of

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resistance is the main reason for limitation in technical application of polyurethanes. The thermal degradation of polyurethanes has been studied by various methods. Mass loss and activation energy of the degradation as a function of soft segment length and

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Conditions are presented for application of the Piloyan method to the DTA of poly-nitro aromatic compounds. Activation energies (E) of the thermal decomposition and the initial valuesT D of the exotherms are determined for trinitrotoluene, trinitro-m-xylene, trinitromesitylene, picryl chloride and dichlorotrinitrobenzene. Linear relationships are derived between the termsE · T

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Abstract  

Using dynamic mechanical analysis (DMA) we have studied the variation with the frequency of the dynamic mechanical properties (storages modulus,E'; loss modulus,E'' and loss tangent or tan σ) for a system containg a diglycidyl ether of bisphenol A (DGEBA) and 1,3-bisaminomethylcyclohexane (1,3-BAC). These properties were measured both in the glass transition and β transition regions. An increase in frequency caused a shift of tan σ peak positions in both regions toward higher temperature. Finally, we report the activation energies of a DGEBA/1,3-BAC expoxy system for α and β transitions.

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Journal of Thermal Analysis and Calorimetry
Authors:
Libby Yoerg
,
M. Ellen Matthews
,
Lakshmi Kaza
,
Naullage Indika Perera
,
David W. Ball
,
John Moran
, and
Alan T. Riga

d -Mannose: 3rd run tan delta curve Activation energies for electrical charging of each of the monosaccharides undergoing molecular rearrangement indicated by the dielectric loss spectra were calculated from an

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energy and pre-exponential factor from the decomposition rate and the values are 112 kJ mol −1 and 4.3 × 10 10 s −1 , respectively. The report indicated that the activation energy remained same for both the cases whilst the pre-exponential factor

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Journal of Thermal Analysis and Calorimetry
Authors:
Vadim V. Krongauz
,
Yann-Per Lee
, and
Anthony Bourassa

constant, f (α) is a function that depends on a reaction mechanism, usually expressed through Gulbert and Waage’s Law of Mass Action [ 40 ]; E a is an apparent activation energy; R is the gas constant; A is preexponential factor. The equation is

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