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Journal of Thermal Analysis and Calorimetry
Authors: José Geraldo de P. Espínola, Evandro P. S. Martins, Franklin P. Aguiar, Haryane R. M. Silva, M. G. Fonseca, L. N. H. Arakaki, and Ercules E. S. Teotônio

obtaining process data from the complex thermal degradation. Theoretical foundations In determining the kinetic trip, activation energy, the pre-exponential factor and the possible decomposition mechanism of the complex, two

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-exponential factor, E a is the activation energy and R is the gas constant. The activation parameters ( A , E a and f ( α )) are often referred in the literature as “kinetic triplet.” Equation ( 1 ) can be transformed to the following expression: (2

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, and 15 K min −1 , in the temperature range of 30–900 °C. Obtained activation energies were 250 kJ kg −1 for polypropylene, 63 kJ kg −1 for the oil shale organic matter, and 242 kJ kg −1 for the mixture. Değirmenci and Durusoy [ 24 ] used the

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crystallization study of amorphous Se 85− x Te 15 Sn x ( x = 0, 2, 4 and 6) glassy alloys have been made using non-isothermal conditions at four different heating rates (5–20 °C min −1 ). From the heating rate dependence, activation energies for glass transition

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crystallization study using different methods for the same experimental data of a glass. The present work studies the crystallization kinetics and evaluates the activation energies for the Se 70 Te 15 In 15 glass under non-isothermal conditions. Using DSC scans

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Abstract  

Two glasses, the first one with the composition of Li2O·2SiO2 and the second one with the addition of CaO, P2O5 and CaF2 in the stoichiometric ratio corresponding to fluoroapatite were prepared and their tendency to crystallize has been studied by non-isothermal DTA analysis. The values of kinetic parameters calculated using the isoconversional integral method have been used to determine the temperature dependencies of both the length of isothermal induction period and the length of overall isothermal crystallization for both glasses. The estimated dependencies indicate that the glass containing CaO, P2O5 and CaF2 has a lower thermal stability.

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Abstract  

Osteoarthritis, although classically conceived of as a degenerative consequence of aging, is a disease with an increasingly well-characterized molecular pathophysiology. Pathologic changes in cartilage composition and molecular organization, as well as elevated water content, alter the exquisite balance of biomechanical properties. Much of what is known about changes in the extracellular matrix in osteoarthritis comes from animal models. Previously, thermogravimetric methods have not been used for compositional thermoanalytical study of normal and degenerative human hyaline cartilage. For this reason the research group established a sufficient new thermogravimetric protocol, which proved water content elevation contributing to disease progression.

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The electrical conductivities and the electronic, IR and NMR spectra were measured for some ethyl cyanoacetate phenylhydrazone derivatives and their lanthanide complexes in the temperature range 20–200‡C. Semiconducting behaviour was detected for these systems (positive dσ/dT). A correlation was established between the electrical properties and the structures of the free ligand molecules and their complexes. The mechanism of the conduction process was evaluated. The electronic absorption spectra in ethanol were measured and are discussed. Elemental analyses were performed and the IR and NMR spectra (of the diamagnetic complexes) were measured to throw more light on the structures of these complexes.

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