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Abstract  

When ethylene-vinyl acetate copolymer, EVA, is heated, a two-stage thermal degradation occurs following its melting. The vinyl acetate content of the copolymer was determined to be 43.8% by using TA 2950 and TA 2050 thermogravimetric instruments. TG/FTIR was used to detect the evolved gas. Acetic acid and trans-1-R-4-R'-cyclohexane were the main products evolved from EVA in the first and second stage, respectively. The apparent activation energies were determined for both stages by differential methods.

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parameters should be avoided, and the different kinetics analysis techniques are complementary rather than competitive [ 45 ]. Thus, the apparent activation energy should be obtained by combining the obtained results in Tables 3 and 4 . The results

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apparent activation energy ( E a ) for dissociation of Mn(CO) 5 from solid Mn 2 (CO) 10 . Unlike traditional mass spectrometry (which involves ionization by high-energy electrons), EGA-IAMS offers a considerable advantage in that it preserves the structure

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Journal of Thermal Analysis and Calorimetry
Authors: Chun-Hong Jiang, Li-Fang Song, Jian Zhang, Li-Xian Sun, Fen Xu, Fen Li, Qing-Zhu Jiao, Zhen-Gang Sun, Yong-Heng Xing, Yong Du, Ju-Lan Zeng, and Zhong Cao

Thermal kinetic parameter for the first-step decomposition of this CoMOF was analyzed using Kissinger method [ 16 ], which has been widely applied to estimate the apparent activation energy. Figure 4 shows the TG curves of the CoMOF measured in air

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Abstract  

Ammonium niobium oxalate was prepared and characterized by elemental analysis, XRD and FTIR spectroscopy analysis, which confirmed that the molecular formula of the complex is NH4(NbO(C2O4)2(H2O)2)(H2O)3. Dynamic TG analysis under air was used to investigate the thermal decomposition process of synthetic ammonium niobium oxalate. It shows that the thermal decomposition occurs in three stages and the corresponding apparent activation energies were calculated with the Ozawa–Flynn–Wall and the Friedman methods. The most probable kinetic models of the first two steps decomposition of the complex have been estimated by Coats–Redfern integral and the Achar–Bridly–Sharp differential methods.

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Abstract  

The space charge trapping/detrapping in thermally charged polyimide (PI) samples have been studied by means of “Final Thermally Stimulated Discharge Current” (FTSDC). We investigate the effects associated with space charge behavior in PI near glass transition region. The FTSDC spectra consist of space charge peak attributed trapping of charges at different trapping levels. The peak positions are found to be very sensitive with poling time, discharging time, and heating rate. The apparent activation energy distributed in the range from 0.51 to 1.12 eV, and the charge released has been found to be varying with poling temperature (T p) and poling time (t c)/discharging time (t d). The decay of space charge (Q) resembled an agreement with interfacial polarization.

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the melt viscosity, which determine hematite proportion and the size of the developing crystals. This article focuses on the kinetics study of the hematite crystallization in an aventurine glaze. The apparent activation energy, as a function of

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apparent activation energy is important as it defines the reactor dimensions and energy consumptions. Activation energy values are dependent on the reducing gases, temperature of reduction, heating rates, presence of impurities, structural imperfections etc

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HPMo ( 1 ), HPVMo ( 2 ), (NH 4 ) 3 PMo ( 3 ), (NH 4 ) 3 HPVMo ( 4 ), (NH 4 ) 2 KHPVMo ( 5 ), (NH 4 ) 1,5 CsH 1,5 PVMo ( 6 ), Cs 3 HPVMo ( 7 ) By means of the well-known Arrhenius equation, the values of apparent activation energy were determined

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