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Journal of Thermal Analysis and Calorimetry
Authors: I. Paukov, Yulia Kovalevskaya, Irina Kiseleva, and Tatiana Shuriga

Introduction This work continues a series of experimental investigations of low temperature heat capacity of the natural micas including ferrous micas, annite [ 1 ] and biotite [ 2 ], and lithium micas, lepidolite [ 3 ] and

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Introduction A comparison of the properties of the crystals of chiral amino acids and of their racemic counterparts attracts much attention. For example, a pronounced difference in the heat capacity [ 1 ], vibrational spectra

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heating rate) and β mean corresponds to the underlying heating rate. There exists different evaluation methods for deriving heat capacity in TMDSC from the raw data obtained. Reading et al. [ 1 ] showed that by superimposing periodic temperature

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: Molar heat capacities of materials at different temperatures are basic data in chemistry and engineering, from which many other thermodynamic properties such as enthalpy, entropy, and Gibbs free energy can be calculated, which are of importance to both

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Journal of Thermal Analysis and Calorimetry
Authors: Igor E. Paukov, Yulia A. Kovalevskaya, Alexei E. Arzamastcev, Natalia A. Pankrushina, and Elena V. Boldyreva

– 22 ] as examples). The aim of this study was to study the heat capacity of this crystal in a wide temperature range by adiabatic calorimetry, to calculate the thermodynamic functions and to compare the results with those previously obtained

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heat capacity of the tellurites is determined using differential scanning calorimeter DSC-III (Setaram, France). The working temperature interval is 300–600 K. The samples are finely ground and sieved through a 0.25 mm 2 sieve. The experimental

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immobilization is their ease of preparation at low temperatures, which is a pre-requisite to avoid loss of volatile fission products from the matrix during materials processing. The heat capacity data of these compounds are of importance to design the process

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Abstract  

Dysprosium hafnate is a candidate material for as control rods in nuclear reactor because dysprosium (Dy) and hafnium (Hf) have very high absorption cross-sections for neutrons. Dysprosium hafnate (Dy2O3·2HfO2-fluorite phase solid solution) was prepared by solid-state as well as wet chemical routes. The fluorite phase of the compound was characterized by using X-ray diffraction (XRD). Thermal expansion characteristics were studied using high temperature X-ray diffraction (HTXRD) in the temperature range 298–1973 K. Heat capacity measurements of dysprosium hafnate were carried out using differential scanning calorimetry (DSC) in the temperature range 298–800 K. The room temperature lattice parameter and the coefficient of thermal expansion are 0.5194 nm and 7.69 × 10−6 K−1, respectively. The heat capacity value at 298 K is 232 J mol−1 K−1.

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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

] or alkaline-earth metals [ 9 ] constructed MOFs are rarely investigated. Actually, these light metals have the priority in building frameworks with light volumetric density and novel topology. Heat capacities determinations of various

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Journal of Thermal Analysis and Calorimetry
Authors: F. Xu, L. Sun, P. Chen, Y. Qi, J. Zhang, J. Zhao, Y. Liu, L. Zhang, Zhong Cao, D. Yang, J. Zeng, and Y. Du

Abstract  

The heat capacities of LiNH2 and Li2MgN2H2 were measured by a modulated differential scanning calorimetry (MDSC) over the temperature range from 223 to 473 K for the first time. The value of heat capacity of LiNH2 is bigger than that of Li2MgN2H2 from 223 to 473 K. The thermodynamic parameters such as enthalpy (HH 298.15) and entropy (SS 298.15) versus 298.15 K were calculated based on the above heat capacities. The thermal stabilities of them were investigated by thermogravimetric analysis (TG) at a heating rate of 10 K min−1 with Ar gas flow rate of 30 mL min−1 from room temperature to 1,080 K. TG curves showed that the thermal decomposition of them occurred in two stages. The order of thermal stability of them is: Li2MgN2H2 > LiNH2. The results indicate that addition of Mg increases the thermal stability of Li–N–H system and decrease the value of heat capacities of Li–N–H system.

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