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Solid adducts, SbBr3 · L (L = pyridine, 2-, 3- and 4-methylpyridine; abbreviated as Py, 2MPy, 3MPy and 4MPy) were synthesized and characterized by elemental analysis and IR spectroscopy. According to the results coordination of nitrogen of aromatic ring with antimony atom was supposed. Kinetic studies were accomplished by using thermogravimetric data obtained through non-isothermal technique. Determination of activation energy and pre-exponential factor was based on the Coats–Redfern integral Ozawa–Flynn–Wall model-free methods. The kinetics parameters Ea, and log A determined at 5 K min−1 were 150.6 kJ mol−1, 16.0 and 122.0 kJ mol−1, 12.4 for SbBr3 · Py and SbBr3 · 4MPy, respectively. [ABSTRACT FROM AUTHOR]

Biodiesel is susceptible to autoxidation if exposed to air, light and temperature, during its storage. Physic nut ( Jatropha curcas L.) seeds show potential application for biodiesel production since its oil yields high quality biodiesel. This work aims to evaluate the thermal behavior of the physic nut oil and biodiesel, from several Brazilian crops, by means of thermoanalytical techniques. Thermogravimetry (TG) and pressurized-differential scanning calorimetry (PDSC) were used in order to determine the applicability of physic nut biodiesel as fuel. Results suggest that physic nut biodiesel is a practical alternative as renewable and biodegradable fuel able to be used in diesel motors. [ABSTRACT FROM AUTHOR]

Cis-norbixin isomer obtained by hydrolysis of cis-bixin and isolated by solvent extraction from annatto seeds. The thermal decomposition data of the cis-norbixin samples were analyzed by thermogravimetric analysis at different heating rates in the 25–900°C temperature range. DSC curves showed that thermal decomposition reactions for cis-norbixin occurred in the solid phase. The kinetic parameters, such as activation energy and pre-exponential factor were determined using integral and approximate methods: Coats–Redfern, Madhusudanan, Horowitz–Metzger and Van Krevelen. F1 mechanism describes well the first stage of the thermal decomposition. [ABSTRACT FROM AUTHOR]

The standard molar enthalpy of formation of crystalline dialkyldithiocarbarnate chelates, [Pd(S2CNR2)2], with R=CH3 and i-C3H7, was determined through reaction-solution calorimetry in 1,2-dichloroethane, at 298 K. Using the standard molar enthalpies of format ion of the gaseous chelates, the homolytic (526±18 and 666±10) and heterolytic (2693±18 and 2957±10 kJ mol-1) mean enthalpies of palladiurn-sulphur bond dissociation were calculated. [ABSTRACT FROM AUTHOR]

The standard molar enthalpies of formation of crystalline dialkyldithiocarbamates chelates, [Pd(S2CNR2)2], with R=C2H5, n-C3H7, n-C4H9 and i-C4H9, were determined through reaction-solution calorimetry in acetone, at 298.15 K. From the standard molar enthalpies of formation of the gaseous chelates, the homolytic (172.4±3.8, 182.5±3.2,150.9±3.1 and 162.6±3.1 kJ mol−1) and heterolytic (745.0±3.8, 803.7±3.3,834.3±3.1 and 735.2±3.0 kJ mol−1) mean palladium-sulphur bond-dissociation enthalpies were calculated. [ABSTRACT FROM AUTHOR]