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Journal of Thermal Analysis and Calorimetry
Authors: Yanni Qi, Jian Zhang, Shujun Qiu, Lixian Sun, Fen Xu, Min Zhu, Liuzhang Ouyang, and Dalin Sun

Abstract  

Polyaniline/NiO (PANI/NiO) composites were synthesized by in situ polymerization at the presence of HCl (as dopant). FTIR, TEM and XRD were used to characterize the composites. Thermogravimetry (TG)–mass spectrometer (MS) and temperature modulated differential scanning calorimetry (TMDSC) were used to study the thermal stability, decomposition and glass transition temperature (T g) of the composites, respectively. FTIR and XRD results showed that NiO nanoparticles connected with PANI chains in the PANI/NiO composites. TEM results exhibited that the morphologies of PANI/NiO composites were mostly spherical, which were different from the wirelike PANI. TG–MS curves indicated that the products for oxidative degradation of both PANI and PANI/NiO composite were H2O, CO2, NO and NO2. TG curves showed that with NiO contents increased in PANI/NiO composites, thermal stability of PANI/NiO composites increased firstly and then decreased when the NiO content was higher than 66.2 wt%. T g of PANI/NiO composites also increased from 163.19 to 252.36 °C with NiO content increasing from 0 to 50 wt%, and then decreased with NiO content increasing continuously.

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Journal of Thermal Analysis and Calorimetry
Authors: L. Yang, Li Sun, Fen Xu, J. Zhang, J. Zhao, Z. Zhao, C. Song, R. Wu, and Riko Ozao

Abstract  

The microcalorimetric method has been used to study the effects of cefpiramide and ceftizoxime sodium on the E. coli growth. The results revealed that these two cephalosporins may alter the metabolic way of the E. coli. Moreover, the lethal doses of cefpiramide and ceftizoxime sodium are 2.000 and 0.2000 μg mL−1, respectively. Combining with the relationships between growth rate constant (k), the maximum power output (P m), the time corresponding to the maximum power output (t m) and cephalosporins concentration (C), one can draw the conclusion that the ceftizoxime sodium has a stronger inhibition effects on the growth of E. coli than that of cefpiramide and they both have the possibility to induce the drug fever.

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Abstract

A three-dimensional lithium-based metal–organic framework Li2(2,6-NDC) (2,6-NDC = 2,6-naphthalene dicarboxylate) has been synthesized solvothermally and characterized by X-ray powder diffraction, elemental analysis, FT-IR spectroscopy, thermogravimetry and mass spectrometer analysis (TG–MS). The framework has exceptional stability and is stable to 863 K. The thermal decomposition characteristic of this compound was investigated through the TG–MS from 293 to 1250 K. The molar heat capacity of the compound was measured by temperature modulated differential scanning calorimetry (TMDSC) over the temperature range from 195 to 670 K for the first time. The thermodynamic parameters such as entropy and enthalpy versus 298.15 K based on the above molar heat capacity were calculated.

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Abstract

Two metal-organic frameworks, Ca(2,6-NDC)(DMF) (1) and Mn3(2,6-NDC)3(DMF)4 (2) (where 2,6-NDC = 2,6-naphthalene dicarboxylate and DMF = N,N′-dimethylformamide) have been solvothermally synthesized under optimized conditions and characterized by X-ray powder diffraction, elemental analysis, FT-IR spectroscopy, and TG analysis. The thermal decomposition characteristics were investigated under air atmosphere from 300 to 1,170 K (for 1) and from 300 to 971 K (for 2). The molar heat capacities were measured from 198 to 548 K (for 1) and from 198 to 448 K (for 2) by temperature modulated differential scanning calorimetry (TMDSC) for the first time. The fundamental thermodynamic parameters such as entropy and enthalpy variations with temperature were calculated based on the experimentally determined molar heat capacities.

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Journal of Thermal Analysis and Calorimetry
Authors: Li-Fang Song, Cheng-Li Jiao, Chun-Hong Jiang, Jian Zhang, Li-Xian Sun, Fen Xu, Qing-Zhu Jiao, Yong-Heng Xing, F. L. Huang, Yong Du, Zhong Cao, Fen Li, and Jijun Zhao

Abstract

One-three-dimensional metal-organic frameworks Mg1.5(C12H6O4)1.5(C3H7NO)2 (MgNDC) has been synthesized solvothermally and characterized by single crystal XRD, powder XRD, FT-IR spectra. The low-temperature molar heat capacities of MgNDC were measured by temperature modulated differential scanning calorimetry (TMDSC) over the temperature range from 205 to 470 K for the first time. No phase transition or thermal anomaly was observed in the experimental temperature range. The thermodynamic parameters of MgNDC such as entropy and enthalpy relative to reference temperature of 298.15 K were derived based on the above molar heat capacities data. Moreover, the thermal stability and decomposition of MgNDC was further investigated through thermogravimetry (TG)–mass spectrometer (MS). Three stages of mass loss were observed in the TG curve. TG–MS curve indicated that the oxidative degradation products of MgNDC are mainly H2O, CO2, NO, and NO2.

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Journal of Thermal Analysis and Calorimetry
Authors: Cheng-Li Jiao, Li-Fang Song, Chun-Hong Jiang, Jian Zhang, Xiao-Liang Si, Shu-Jun Qiu, Shuang Wang, Li-Xian Sun, Fen Xu, Fen Li, and Ji-Jun Zhao

Abstract

The low-temperature molar heat capacity of crystalline Mn3(HEDTA)2·10H2O was measured by temperature-modulated differential scanning calorimetry (TMDSC) for the first time. The thermodynamic parameters such as entropy and enthalpy relative to 298.15 K were calculated based on the above molar heat capacity data. The compound was characterized by powder XRD, FT-IR spectrum. Moreover, the thermal decomposition characteristics of Mn3(HEDTA)2·10H2O were investigated by thermogravimetry–mass spectrometer (TG–MS). The experimental result through TG measurement shows that a three-step mass loss process exists. H2O, CO2, NO, and NO2 were observed as products for oxidative degradation of Mn3(HEDTA)2·10H2O from the MS curves.

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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

Abstract

A novel metal organic framework [Co (BTC)1/3 (DMF) (HCOO)]n (CoMOF, BTC = 1,3,5-benzene tricarboxylate, DMF = N,N-dimethylformamide) has been synthesized solvothermally and characterized by single crystal X-ray diffraction, X-ray powder diffraction, and FT-IR spectra. The molar heat capacity of the compound was measured by modulated differential scanning calorimetry (MDSC) over the temperature range from 198 to 418 K for the first time. The thermodynamic parameters such as entropy and enthalpy versus 298.15 K based on the above molar heat capacity were calculated. Moreover, a four-step sequential thermal decomposition mechanism for the CoMOF was investigated through the thermogravimetry and mass spectrometer analysis (TG-DTG-MS) from 300 to 800 K. The apparent activation energy of the first decomposition step of the compound was calculated by the Kissinger method using experimental data of TG analysis.

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Journal of Thermal Analysis and Calorimetry
Authors: Li-Fang Song, Chun-Hong Jiang, Jian Zhang, Li-Xian Sun, Fen Xu, Yun-Qi Tian, Wan-Sheng You, Zhong Cao, Ling Zhang, and Dao-Wu Yang

Abstract  

A novel two-dimensional metal organic framework MgBTC [MgBTC(OCN)2·2H2O, where BTC = 1,3,5-benzenetricarboxylate] has been synthesized solvothermally and characterized by single crystal XRD, powder XRD, FT-IR spectra. The low-temperature molar heat capacities of MgBTC were measured by temperature modulated differential scanning calorimetry (TMDSC) over the temperature range from 190 to 350 K for the first time. No phase transition or thermal anomaly was observed in the experimental temperature range. The thermodynamic parameters of MgBTC such as entropy and enthalpy relative to reference temperature of 298.15 K were derived based on the above molar heat capacities data. Moreover, the thermal stability and decomposition of MgBTC was further investigated through thermogravimetry (TG)-mass spectrometer (MS). Four stages of mass loss were observed in the TG curve. TG-MS curve indicated that the products of oxidative degradation of MgBTC are H2O, N2, CO2 and CO. The powder XRD showed that the mixture after TG contains MgO and graphite.

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Journal of Thermal Analysis and Calorimetry
Authors: Yi-Xi Zhou, Li-Xian Sun, Zhong Cao, Jian Zhang, Fen Xu, Li-Fang Song, Zi-Ming Zhao, and Yong-Jin Zou

Abstract

Two metal–organic frameworks (MOFs) of M(HBTC)(4,4′-bipy)·3DMF [M = Ni (for 1) and Co (for 2); H3BTC = 1,3,5-benzenetricarboxylic acid (1,3,5-BTC); 4,4′-bipy = 4,4′-bipyridine; DMF = N,N′-dimethylformamide] were synthesized by a one-pot solution reaction and a solvothermal method, respectively, and characterized by powder X-ray diffraction and FT-IR spectra. The low-temperature molar heat capacities of M(HBTC)(4,4′-bipy)·3DMF were measured by temperature-modulated differential scanning calorimetry (TMDSC) for the first time. The thermodynamic parameters such as entropy and enthalpy relative to reference temperature 298.15 K were derived based on the above molar heat capacity data. Moreover, the thermal stability and the decomposition mechanism of M(HBTC)(4,4′-bipy)·3DMF were investigated by thermogravimetry analysis (TGA). The experimental results through TGA measurement demonstrate that both of the two compounds have a three-stage mass loss in air flow.

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Journal of Thermal Analysis and Calorimetry
Authors: Li-Fang Song, Chun-Hong Jiang, Cheng-Li Jiao, Jian Zhang, Li-Xian Sun, Fen Xu, Qing-Zhu Jiao, Yong-Heng Xing, Yong Du, Zhong Cao, and Feng-Lei Huang

Abstract

A metal-organic framework [Mn(4,4′-bipy)(1,3-BDC)]n (MnMOF, 1,3-BDC = 1,3-benzene dicarboxylate, 4,4′-bipy = 4,4′-bipyridine) has been synthesized hydrothermally and characterized by single crystal XRD and FT-IR spectrum. The low-temperature molar heat capacities of MnMOF were measured by temperature-modulated differential scanning calorimetry for the first time. The thermodynamic parameters such as entropy and enthalpy relative to reference temperature 298.15 K were derived based on the above molar heat capacity data. Moreover, the thermal stability and the decomposition mechanism of MnMOF were investigated by thermogravimetry analysis-mass spectrometer. A two-stage mass loss was observed in air flow. MS curves indicated that the gas products of oxidative degradation were H2O, CO2, NO, and NO2.

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