| Autor: |
Xinmin, W., Chuansong, Q., Songsheng, Q., Zhicheng, T. |
| Předmět: |
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| Zdroj: |
Journal of Thermal Analysis & Calorimetry; Nov2007, Vol. 90 Issue 2, p569-573, 5p, 1 Diagram, 3 Charts, 1 Graph |
| Abstrakt: |
Rare-earth perchlorate complex coordinated with glycine [Nd2(Gly)6(H2O)4](ClO4)6·5H2O was synthesized and its structure was characterized by using thermogravimetric analysis (TG), differential thermal analysis (DTA), chemical analysis and elementary analysis. Its purity was 99.90%. Heat capacity measurement was carried out with a high-precision fully-automatic adiabatic calorimeter over the temperature range from 78 to 369 K. A solid-solid phase transformation peak was observed at 256.97 K, with the enthalpy and entropy of the phase transformation process are 4.438 kJ mol−1 and 17.270 J K−1 mol−1, respectively. There is a big dehydrated peak appears at 330 K, its decomposition temperature, decomposition enthalpy and entropy are 320.606 K, 41.364 kJ mol−1 and 129.018 J K−1 mol−1, respectively. The polynomial equations of heat capacity of this compound in different temperature ranges have been fitted. The standard enthalpy of formation was determined to be −8023.002 kJ mol−1 with isoperibol reaction calorimeter at 298.15 K. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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