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Journal of Thermal Analysis and Calorimetry
Authors: Marcelo Kobelnik, Clóvis A. Ribeiro, Diógenes dos Santos Dias, Sonia de Almeida, Marisa Spirandeli Crespi and Jorge M. V. Capela

(II)–diclofenac (Co(Diclof) 2 in a solid state. This compound was evaluated by simultaneous thermogravimetry-differential thermal analysis (TG/DTA), differential scanning calorimetry (DSC), and X-ray powder diffractometry. The results of this study

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Journal of Thermal Analysis and Calorimetry
Authors: Seied Mahdi Pourmortazavi, Mehdi Rahimi-Nasrabadi, Iraj Kohsari and Seiedeh Somayyeh Hajimirsadeghi

/potassium chlorate mixtures by simultaneous thermogravimetry-differential thermal analysis . J Therm Anal Calorim . 84 : 557 – 561 10.1007/s10973-005-7008-x . 6. Santos , AFO

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Journal of Thermal Analysis and Calorimetry
Authors: Viorel Sasca, Elena Mosoarca, Livia Avram, Ramona Tudose and Otilia Costisor

Abstract  

The thermal decomposition of Mannich base N,N′-tetra(4-antipyrylmethyl)-1,2-diaminoethane (TAMEN), and its Ni(II), binuclear complex, Ni2(TAMEN)Cl4, in air and in nitrogen atmosphere, were investigated. X-ray powder diffractometry, infrared spectroscopy and simultaneous thermogravimetry-differential thermal analysis (TG-DTA), have been used to characterize and to study the thermal behavior of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and decomposition mechanism of the compound.

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Abstract  

Solid-state Ln(Bz)3·H2O compounds where Ln stands for trivalent yttrium or lanthanides and Bz is benzoate have been synthesized. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), X-ray powder diffractometry, infrared spectroscopy and chemical analysis were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, thermal stability and thermal decomposition of the isolated compounds.

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Solid-state compounds of 2-methoxybenzylidenepyruvate with some bivalent metal ions

Synthesis, characterization and thermal behavior studies

Journal of Thermal Analysis and Calorimetry
Authors: M. Kobelnik, E. Schnitzler and M. Ionashiro

Abstract  

Solid-state M-2-MeO-BP compounds, where M represents bivalent Mn, Fe, Co, Ni, Cu, Zn and 2-MeO-BP is 2-methoxybenzylidenepyruvate have been synthesized. Simultaneous thermogravimetry-differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), X-ray powder diffractometry, infrared spectroscopy, elemental analysis and complexometry were used to characterize and to study the thermal stability and thermal decomposition of these compounds. The results led to information about the composition, dehydration, crystallinity and thermal decomposition of the isolated compounds.

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Abstract  

Combustion experiments of three typical seaweeds (Gracilaria cacalia, Enteromorpha clathrata and Laminaria japonica) have been studied using a DTA-60H Thermal Analyzer and the combustion processes and characteristics are studied. Thermogravimetric experiments are carried out on the samples with 0.18 mm particle size at the heating rate of 20°C min−1. The results indicate that the ignition mode of seaweed is homogeneous and the combustion process is composed of dehydration, the pyrolysis and combustion of volatile, transition stage, the combustion of char as well as the reaction at high temperature. And the combustion characteristic parameters are obtained such as ignition temperature, maximum rate of combustion, burnout temperature etc. The combustion models of these seaweeds are also analyzed. The combustion characteristics and model differences between the seaweed and woody biomass are caused by the differences of volatile components. The combustibility indexes of seaweeds calculated are better than that of woody biomass, and the index of Gracilaria cacalia is the best. At last, activation energies are determined using Arrhenius model that is solved by binary linear regression method.

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Journal of Thermal Analysis and Calorimetry
Authors: Elena Mosoarca, Sasca Viorel, Livia Avram, Ramona Tudose and Otilia Costisor

Abstract  

The thermal decomposition in air and in nitrogen atmosphere of binuclear complex compounds of Cu(II) and Co(II) containing the Mannich base N,N′-tetra(4-antipyrylmethyl)-1,2 diaminoethane (TAMEN) as a ligand, Cu2(TAMEN)Cl4 and Co2(TAMEN)Cl4, were investigated. X-ray powder diffractometry, infrared spectroscopy and simultaneous thermogravimetry-differential thermal analysis (TG-DTA), have been used to characterize and to study the thermal behavior of these compounds. The results provided information concerning the stoichiometry, crystallinity, thermal stability and decomposition mechanism of the compounds.

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Abstract  

Three bio-fuels with or without additives and their fly ash samples were characterized using simultaneous Thermogravimetry-Differential Thermal Analysis-Fourier Transform Infrared Spectrometry-Mass Spectrometry (TG-DTA-FTIR-MS), X-ray Diffraction (XRD), X-ray Fluorescence (XRF), and Scanning Electron Microscopy-Energy Dispersive Spectrometry (SEM-EDS). The results show that the additives increase the reactivity of the bio-fuel during combustion. The additives also significantly decrease the amount of unburned carbon in the fly ash. The additives affect the compounds formed in the fly ash sample, and consequently the thermal behaviour of the fly ash. The fly ash samples are thermally stable in air up to 100C. The fly ash samples contain fine particles with irregular shape, small round particles, and large hollow spherical particles with entrapped gases.

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Studies on energetic compounds

Part 40. Kinetics of thermal decomposition of some bis(propylenediamine)metal perchlorate complexes

Journal of Thermal Analysis and Calorimetry
Authors: G. Singh and D. K. Pandey

Bis(propylenediamine)metal perchlorate (BPMP) complexes like [M(pn)2](ClO4)2 (where M=Cr, Mn, Ni, Cu, Zn and pn=propylenediamine) have been prepared and characterized by gravimetric methods, infrared and elemental analysis. Thermal properties have been studied using simultaneous thermogravimetry-differential thermal analysis in atmospheres of nitrogen and air to examine the effect of atmospheric change on thermal decomposition of these complexes. Changing of the atmosphere does not cause any measurable changes in the decomposition of complexes. However, as indicated by thermoanalytical techniques, the thermal stability of present complexes decreases in the order: [Cr(pn)2](ClO4)2>[Mn(pn)2](ClO4)2>[Zn(pn)2](ClO4)2>[Ni(pn)2](ClO4)2>[Cu(pn)2](ClO4)2. Isothermal thermogravimetry, over the temperature range of decomposition has been done for all the complexes. An analysis of the kinetics of thermal decomposition was made using a model fitting procedure as well as an isoconversional method, independent of any model. The results of both kinetic approaches have been discussed critically. The explosion delay (D E) was measured to investigate the trend of rapid thermal analysis.

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Abstract  

In this present work, barium ion was reacted with different ligands which are 5,7-dibromo 5,7-dichloro, 7-iodo and 5-chloro-7-iodo-8-hydroxyquinoline, in acetone/ammonium hydroxide medium under constant stirring and the obtained compounds were as follows: (I) Ba[(C9 H4 ONBr2 )2 ]⋅1.5H2 O; (II) Ba[(C9 H4 ONCl2 )(OH)]⋅1H2 O; (III) Ba[(C9 H5 ONI)2 ]⋅1H2 O and (IV) Ba[(C9 H4 ONICl)2 ]⋅5H2 O, respectively. The compounds were characterized by elemental analysis, infrared absorption spectrum (IR), inductively coupled plasma spectrometry (ICP), simultaneous thermogravimetry-differential thermal analysis (TG-DTA) and differential scanning calorimeter (DSC). The final residue of the thermal decomposition was characterized as orthorhombic BaBr2from (I); the intermediate residue, as a mixture of orthorhombic BaCO3 and BaCl2 and cubic BaO and the final residue, as a mixture of cubic and tetragonal BaO and orthorhombic BaCl2 (II); the intermediate residue, as orthorhombic BaCO3 and as a final residue, a mixture of cubic and tetragonal BaO from (III); and the intermediate residue, as a mixture of orthorhombic BaCO3 and BaCl2 and as a final residue, a mixture of cubic and tetragonal BaO and orthorhombic BaCl2 from (IV).

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