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]. The final properties and thermal behavior of thermosets depend mainly on the degree of crosslinking of the polymer, which is determined by the functionality of the reactive monomers and the stoichiometry of the reaction [ 3 ]. The presence of the

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,3-dinitroazetidine (DNAZ, pK b = 6.5) [ 3 , 4 ] can prepare a variety of solid energetic DNAZ salts with high oxygen-balance [ 3 , 5 – 11 ]. In this study, the energetic salt of DNAZ with perchloric acid (HClO 4 ) was synthesized, its thermal behavior was studied

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their medicinal properties [ 2 , 3 ]. The thermal behaviour of the edible mushroom species is not yet to be found in the scientific literature. Since these mushrooms are used for food either as such or thermally processed in industry

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Abstract  

An improved method for the synthesis of four heterotrinuclearpolyacids of the type: Hx[EM′yM″zO40nH2O (E=P, Si; M′=Mo, W; M″=V, W) was elaborated. The studied compounds were characterized by elemental analysis, IR spectra and thermal behaviour over 20–800C temperature range.

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Abstract  

Thermal behaviour of raw fly ashes-wasted products from various Polish power plants has been investigated using X-ray diffractions (XRD), Fourier transform infrared spectroscopic (FT-IR), differential thermal analysis (DTA) and thermogravimetry (TG). On the basis of the DTA and TG analysis differentiation between examined ashes has been made, which could not be achieved by XRD and FT-IR methods.

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Abstract  

The paper describes the synthesis of low molecular mass poly(allyl chloride) (PAC) (M n= 856-3834 g mol-1) using Lewis acid (ALCL3, FeCL3, TiCL4) and al powder. Branching in PAC was indicated on the basis of elemental analysis and 1H-NMR spectroscopy. azidation of pac could be carried out at 100°C by using NaN3 and DMSO as solvent. Curing of poly(allyl azide) (PAA) by cyclic dipolar addition reaction with EGDMA (ethylene glycol dimethacrylate, 5-45 phr) was investigated by differential scanning calorimetry and structure of cured polymer was confirmed by FTIR. A two-step mass loss was exhibited by uncured and cured PAA in nitrogen atmosphere. A mass loss of 20-28% (155-274°C) and 50-61% (330-550°C) was observed.

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Journal of Thermal Analysis and Calorimetry
Authors: Agnieszka Jabłońska–Wawrzycka, Małgorzata Zienkiewicz, Maciej Hodorowicz, Patrycja Rogala, and Barbara Barszcz

gain information on: influence of the type of manganese(II) salt applied to the synthesis on the product of the reaction; influence of the furnace atmosphere on the thermal behavior and on

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Journal of Thermal Analysis and Calorimetry
Authors: E. Plevová, A. Kožušníková, L. Vaculíková, and G. Simha Martynková

Abstract  

The definition as well as prediction of rock thermal behavior seems to be a quite difficult problem significantly effected by rock composition and structure. Temperature increase causes various changes of rock material (such as decomposition, oxidation, phase and polymorphic transformation, etc.). These changes are connected to thermal expansion with following appearance of tensions and cracks in minerals and rock structure. After consequential temperature decrease, developed tensions and cracks still influence the process. This study presents the application of thermogravimetric analysis, differential thermal analysis and thermomechanical analysis in characterization of selected marble thermal behavior. The texture and morphological orientation of calcite grains for marble samples was determined by optical microscopy. FTIR spectroscopy application along with X-ray diffraction (XRD) extended data about mineralogical composition. According to optical microscopy, the calcite grains show marked morphological anisotropy in one direction for some samples. Therefore, the thermal expansion had to be measured in three different (perpendicular to each other) directions. It is evident, that the effect of temperature on the final marble properties depends not only on mineralogical composition, but also on structure, texture and morphological orientation of grains. All these facts significantly influence the interpretation of differences in various marble thermal behavior.

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Abstract  

The thermal behaviour of ammonium oxofluorotitanates (NH4)3TiOF5, (NH4)2TiOF4 and NH4TiOF3 was investigated by thermoanalytical, X-ray and IR spectroscopic methods. The first decomposition stages under quasi-isobaric conditions are characterized by the formation of (NH4)2TiF6 and ammonium oxofluorotitanate with the less content of ammonium and fluorine than in the initial compound. The decomposition process is accompanied by the Ti(IV) reducing due to ammonia evolved. The new ammonium oxofluorotitanate of high volatility was isolated and characterized. Ammonium-containing non-stoichiometric titanium oxyfluorides are the final products of thermal decomposition of ammonium oxofluorotitanates.

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Journal of Thermal Analysis and Calorimetry
Authors: L. Ji-zhen, F. Xue-zhong, H. Rong-zu, Z. Xiao-dong, Z. Feng-qi, and G. Hong-Xu

Abstract  

The thermal behavior of copper(II) 4-nitroimidazolate (CuNI) under static and dynamic states are studied by means of high-pressure DSC (PDSC) and TG with the different heating rates and the combination technique of in situ thermolysis cell with rapid-scan Fourier transform infrared spectroscopy (thermolysis/RSFTIR). The results show that the apparent activation energy and pre-exponential factor of the major exothermic decomposition reaction of CuNI obtained by Kissinger’s method are 233.2 kJ mol−1 and 1017.95 s−1, respectively. The critical temperature of the thermal explosion and the adiabatic time-to-explosion of CuNI are 601.97 K and 4.4∼4.6 s, respectively. The decomposition of CuNI begins with the split of the C-NO2 and C-H bonds, and the decomposition process of CuNI under dynamic states occurs less readily than those under static states because the dynamic nitrogen removes the strong oxidative decomposition product (NO2). The above-mentioned information on thermal behavior is quite useful for analyzing and evaluating the stability and thermal charge rule of CuNI.

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