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XPOWDER analytical software was used for the semi-quantitative determination of the mineral phases. A Perkin Elmer STA6000 device was used for the thermogravimetrical analysis (TG/DTG-DTA). Approximately 10 mg of powdered mortars were placed in

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Abstract  

Roman ancient mortars have been widely studied, in connection with both diagnosis and application required for restoring. Thermoanalytical experiments performed on mortars from Pompeii and Herculaneum provided a very good understanding of the technology employed. The mortars from Pompeii were obtained by the proper mixing of lime and marble grains while mortars of Herculaneum by lime and silicates compounds. The position of the endothermic peak of calcite decomposition showed important variations in the different samples studied, which was assigned to the different crystallinity and particle sizes. Experiments under CO2 flow confirmed the presence of magnesium calcium carbonates.

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internal magnetic field ( H eff ) as well as the line widths (FWHM) and the relative weight of spectral partial components ( G ) were determined. The TG–DTG–DTA-analyses were conducted with thermal complex Stanton Redcroft (England). The samples

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Journal of Thermal Analysis and Calorimetry
Authors: C. Moldoveanu, Lucia Odochian, I. Mangalagiu, M. Dumitraş, and N. Apostolescu

Abstract  

The study is devoted to the characterization by TG, DTG, DTA, both in air and N2 atmosphere, of three cyclic ylides as well as two spirane derivatives, to the purpose of elucidating the correlation between structure, thermostability and thermal degradation mechanism. Thermal analysis data indicated that the degradation mechanism is characteristic for every sample, and the consequences of structural peculiarities are discussed. The thermostability series of the samples is correlated to their structure. The quantitative TG-DTG-DTA analysis allowed some considerations on the thermal degradation mechanism, subsequently confirmed by mass spectrometry. The melting points obtained by DTA and Boetius measurements along with the initial degradation temperatures from TG-DTG-DTA curves indicates the temperature range for the use and storage of these compounds, considering that some derivatives of cyclic ylides show biological activity and potential medical applications.

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The thermal decomposition of [Co(NH3)5CO3]NO3, [Co(NH3)5NO2](NO3)2 and [Co(NH3)5H2O](NO3)3 complexes was studied by simultaneous TG, DTG, DTA (Derivatograph-C), termogastitrimetry, continuous selective water detection, TG-MS, and XRD methods.

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The results of comparative thermal analysis (TG-DTG-DTA-DSC) of the thermal decomposition of hexamminecobalt(III) chloride in air atmosphere are reported. The kinetics and mechanism of the thermal decomposition, the process enthalpy and the variation in specific thermal capacity of the solid product reaction with temperature were determined.

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Journal of Thermal Analysis and Calorimetry
Authors: Z. D. Zivkovic, N. Milosavljevic, M. Grotowska, and W. Wojciechowski

In this paper the results of comparative thermal analysis TG-DTG-DTA-DSC for the thermal decomposition process of [Cr(NH3)6]Cl3 in air atmosphere are given. The kinetics and mechanism of this complex thermal decomposition, process enthalpy as the changes of specific thermal capacity of solid products reaction with temperature were determined.

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Abstract  

This research comprises the applicability of complex thermal analysis technique (TG/DTG, DTA) in the determination of calorific values of coals of different origin. The calorific values, those obtained by thermal analysis are compared with an adiabatic bomb calorimeter by the standard ASTM method, and the results are discussed.

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Abstract  

The thermal decomposition reactions of calcitic dolomite were investigated. Simultaneous TG/DTG/DTA were applied under non-isothermal conditions. From the recorded curves, the activation energies, pre-exponential factors and thermodynamic parameters of activation were calculated for the two thermal decomposition steps.

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Studies on (non) energetic compounds

Part 38. Kinetics of thermolysis of dichloroanilinium bromide salts

Journal of Thermal Analysis and Calorimetry
Authors: G. Singh, P. Srivastava, and J. Srivastava

Abstract  

Five salts of dichloroanilinium bromide (DCABr) were prepared and characterized by elemental and spectral studies. The thermal decomposition of DCABr was studied by using TG-DTG-DTA techniques and the results are discussed here. Kinetic parameters with the help of model fitting and isoconversional methods have been evaluated critically. A mechanism of decomposition has also been suggested.

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