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Abstract  

Metalorganic complexes of copper have been synthesized by modifying the ligand in the β-diketonate class of compounds. Detailed thermal analysis of several β-diketonate complexes of copper has been carried out to evaluate their suitability as precursors for chemical vapor deposition (CVD). A comparison of their relative volatilities has been made by determining their sublimation rates at different temperatures. Thermal analyses of these complexes reveal significant differences among their volatilities and decomposition patterns.

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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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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  

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  

Syrian phosphorite is subjected to mechanochemical activation carried out in planetary mill. Some phase transformations are ascertained by means of powder XRD and thermal analyses. They reveal as partial transformation of carbonate fluorine apatite into carbonate hydroxyl fluorine apatite and formation of Ca(PO3)2, as well. The solubility of the activated sample in 2% citric acid is increased as a result of these changes.

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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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Summary Thermomagnetometry has been applied to mineralized archaeological iron samples and samples from accelerated corrosion tests. It has successfully quantified the degree of corrosion, measured by the loss of iron, as well as the amount of magnetite formed and water held in the corrosion and adhered soil layers. Thermomagnetometry, thermogravimetric analysis and differential scanning calorimetry have been applied to the reported corrosion products from archaeological iron. Fourier transform infra-red and Raman spectroscopies and X-ray diffraction analyses were undertaken on the residues and at intermediate heating stages, where the thermal analyses indicated, to identify the reaction products.

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Abstract  

A Spanish hazardous waste from tertiary aluminium industry was used as a raw material for the synthesis of calcium aluminate. An amorphous precursor was obtained by a hydrothermal method at different values of pH. The transformation of the precursor in a crystalline aluminate was followed by TG/DTA up to 1300 °C. At temperatures between 719 and 744 °C, the precursors evolve towards the formation of C12A7 which becomes CA at circa 1016 °C. Mass spectrometry coupled to thermal analyser allowed the identification of the decomposition products.

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Abstract  

A complex of devices is described which consists of two thermal analysers (their working temperature ranges are 300–2500 K and 1000–3000 K) and a scanning calorimeter (its working temperature ranges from 300 to 2000 K) which are controlled by an automatic system based on IBM PC AT with the ADDA-14 card.

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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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