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Reaction Kinetics, Mechanisms and Catalysis
Authors: Susana Pinto-Castilla, Santiago Marrero, Yraida Díaz, Joaquín L. Brito, Pedro Silva, and Paulino Betancourt

passivated in a flow of ~1 % (v/v) O 2 /N 2 for 2 h. Characterization Elemental analysis was made by flame absorption atomic spectroscopy by the Centro de Química Analítica-UCV, Venezuela. The surface area, pore

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important role on the preparation of materials and the later treatment. However, with the appearance in the new and complex organic–inorganic materials, the single TA technique cannot fulfill their characterization. It is necessary to study the thermal

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Journal of Thermal Analysis and Calorimetry
Authors: J. Orbán, Kinga Pozsonyi, Krisztina Szarka, Szilvia Barkó, Emőke Bódis, and D. Lőrinczy

Abstract  

The thermodynamic properties of the ADP- and ATP-actin filaments were compared by the method of differential scanning calorimetry. The lower melting point for the ADP-F-actin filament (58.4 vs. 64.5°C for ATP-F-actin) indicated that compared to the ATP-actin filaments its structure was less resistant to heat denaturation. The detailed thermodynamic characterisation of the proteins was carried out by the analysis of the calorimetric enthalpy, the entropy and the free enthalpy changes. All of the determined parameters gave lower values to the ADP-actin filaments than to the ATP-actin filaments. The calculated values of the activation energy also demonstrated that compared to the ADP-F-actin the ATP-F-actin was thermodynamically more resistant to the denaturing effect of heat. Based on all of this information we have concluded that the actin filament prepared from ADP containing magnesium saturated actin monomers at pH 8.0 is thermodynamically less stable than the ones obtained from ATP-actin monomers.

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Abstract  

The thermal decomposition of electrolytic manganese dioxide (EMD), in an inert atmosphere, and the effect of chemical reduction on EMD, using 2-propanol under reflux (82C), was investigated by differential scanning calorimetry (DSC). This study is an extension of a study investigating the thermal decomposition of EMD and reduced EMD by TG-MS (J. Therm. Anal. Cal., 80 (2005)625)). The DSC characterisation was carried out up to 600C encompassing the water loss region up to 390C and the first thermal reduction step. Water removal was observed in two distinct endothermic peaks (which were not deconvolved in the TG-MS) associated with the removal of bound water. For the lower degrees of chemical reduction, thermal reduction resulted in the formation of Mn2O3; for higher degrees of chemical reduction, the thermal reduction resulted in Mn3O4 at 600C. In the DSC the thermal reduction of the EMD and chemically reduced specimen was observed to be endothermic. The reduced specimens, however, also showed an exothermic structural reorganisation.

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complete thermal characterization of mica composite, its components (resin, hardener, accelerator, and mica tape) and thermoanalytical interactions between them. The properties of the system, which is so relevant to its great electrical and thermal

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studies are developed related to the characterization, recycling, and solution of this waste [ 8 – 10 ]. Other different wastes and residues are generated in the aluminum industry. One such waste is a very fine black powder produced during the calcination

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Abstract  

Compositional characterisation aspects of materials of interest to the electronics industry are briefly reviewed based on the work carried out in car laboratory.

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of properties meant to characterize the continuum of materials comprising SOM in terms of how easily organic carbon present in the soil can be mineralized by the microbial community [ 3 ]. Characterization of SOM quality is critical because of its

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to damping ratio < 1. The activation energy, E a , and frequency factor, A , from temperature of onset to peak temperature are listed in Table 1 . From the above thermodynamical characterization, the structure of complex was found as in

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Abstract  

We give a new characterization of the logarithm as an additive arithmetical function.

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