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Abstract  

Copper complexes of some 1-phenyl-3-methyl-4-acyl-5-pyrazolones have been prepared. The complexes were characterized by elemental analyses and thermal analyses. It was shown that the melting points decrease linearly in increasing the molecular weight of the complexes.

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Abstract  

For two typical actuators of intelligent systems (Ni–Ti SMA cantilever and SMA helical spring), the evaluation of their thermal characteristics is presented. In order to determine the transformation temperatures and other thermal parameters of the two studied elements, the attention was concentrated on thermal analysis experiments. For each actuator configuration, comprehensive graphical interfaces have been developed, to run in Visual Basic, with respect to the results of performed thermal analyses.

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Thermal decomposition of the amorphous coprecipitate of yttrium and aluminium hydroxides forming yttrium aluminium garnet has been investigated employing thermal analyses, X-ray diffraction and IR spectroscopy. On heating, the coprecipitate progressively loses water forming a stable but highly disordered hydroxy garnet which crystallizes at ∼1180 K and decomposes to YAG at ∼1290 K. Nucleation of the crystalline phase appears to begin at ∼800 K.

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Abstract  

This paper presents the results of oxyreactive thermal analyses of organic matter in rocks, heated naturally during diagenetic to metamorphic processes. During the experiments we traced the reactions in the temperature range up to 900C, it means from the very beginning of diagenetic transformations to the highest real temperatures acting in the Earth's crust as a solid phase. The results showed that TA could be a tool for the reconstruction of thermal regime in natural coal-bearing systems.

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Abstract  

Thirteen tellurites of rare-earth elements from cerium group (Sc, La, Ce, Pr, Nd, Sm, Eu) have been synthesized and characterized by chemical, X-ray and thermal analyses. The space group, crystal systems and parameters of the elementary cells of most of the tellurites have been established. The temperatures, enthalpies and entropies of melting were measured. The change of melting temperatures vs. ion radius occurs gradually in a uniform mode with some exceptions.

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Abstract  

There has been a significant research effort on the development of an oil industry based on Australian oil shales. However, to date the research has been based mainly on the processing aspects of oil shale. The thermal analyses of oil shales, while having been the subject of many studies, have been limited to some extent by instrumentation and analytical techniques. This paper reports on thermal analysis studies utilising traditional thermogravimetry/differential thermal analysis (TG/DTA) and differential scanning calorimetry (DSC). The application of modern thermal analysis techniques such as high resolution TG (HRTG) and modulated differential scanning calorimetry (MDSC) is also examined and compared to the traditional methods.

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Abstract  

The influence of certain experimental conditions on the courses of the thermal curves (DTA and DTG) of selected clay minerals was studied. The thickness of the sample layer, the sample mass, the type of sample holder and the parameters of the air atmosphere were varied in thermal analyses of 13 samples of clay minerals. Comparison of the results obtained on different clay samples analysed under different experimental conditions may serve as the basis for the improvement of the thermal analysis methodology applied for the study of clay minerals.

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Abstract  

The recovery of metals is the process of softening without crystallization in the mechanical stressed pieces and is well characterized by DSC measurements at temperatures < 600C. The present investigation was undertaken to detect similar effects also in traditional ceramics. Several ceramic samples, coming from different productions, were thermally analyzed by DSC and the presence, in the most stressed samples, of an exothermic peak at about 350C, was detected, confirming the presence of recovery in the ceramics too. However, owing to the complex structures of these materials, at present no mathematical model could be introduced.

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Journal of Thermal Analysis and Calorimetry
Authors: A. Barros, S. Prasad, V. Leite, A. Souza, G. Marino, Crislene Morais, and Marta Conceição

Abstract  

The present study was carried out for evaluating the retention behavior of sanitary sewage in relation to cadmium and cobalt ions in an ascendant continuous-flow reactor. It was found that the studied sludge presented a high assimilation of the metals, probably due to the presence of anionic groups, which favors adsorption and complexation processes. Thermal analyses of the samples showed a shift in the thermal decomposition of the ‘in natura’ sludge, when compared with those of the samples spiked with the metals, confirming the possibility of interactions between the heavy metals and the anionic groups present in the sludge.

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Abstract  

The focus of this work is the use of thermal analyses and Fourier Transform Infrared Spectroscopy (FTIR) for characterization of the gel decomposition, resulting from the formation of Y-barium hexaferrite substituted by Zn ions (Zn-Y-barium hexaferrite). Samples with Ba2Zn2Fe12O22 composition were synthesized by the citrate auto-combustion method. During the TG experiments the highest mass loss was attributed to citrate decomposition owing to the self-combustion reaction, confirmed by the disappearance of –OH band, and the drastic decrease of –CO2 and –NO3 bands. Zn substitution resulted in an X-band microwave absorber material.

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