Cui, Yunlong Y Wu, Javier Y Kamanina, Natalie Y Pasaje, Alfredo Y Leyderman, Alexander Y Barrientos, Alfonso Y Vlasse, Marcus Y Penn, Benjamin G (1999) Dielectric study of dynamics of organic glasses. Journal of Physics D: Applied Physics, 32 (24). pp. 3215-3221.
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Resumen
The dynamics of organic compounds 2-cyclo-octylamino-5-nitropyridine (COANP), (S)-2-N--(methylbenzylamino)-5-nitropyridine (MBANP), 2-(N-prolinol)-5-nitropyridine (PNP), and N-(4-nitrophenyl)-(L)-prolinol (NPP) were studied by dielectric relaxation spectroscopy in the frequency range of 10 Hz-2 MHz and differential scanning calorimetry (DSC). The dielectric and DSC studies showed that COANP, MBANP and PNP underwent glass transition. However, NPP crystallized so rapidly upon cooling that the glass state could not be observed. It was found that the crystalline process of COANP did not slow the structure relaxation of COANP glass. The relaxation times fitted well to the empirical Vogel-Fulcher equation = expEa/kb(T-TVF). The activation energies Ea and the Vogel-Fulcher temperature TVF were 54.5 meV and 239 K for COANP, 86.2 meV and 249 K for MBANP and 84.9 meV and 245 K for PNP, respectively. The crystalline temperatures of COANP and MBANP were given as 300 K and 330 K, respectively. An anomalous behaviour of the dielectric permittivity of PNP glass was observed.
Tipo de Elemento: | Artículo |
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Asunto: | Q Ciencias > QC Physics |
Division: | Facultad de Ciencias Exactas y Naturales > Programa de Física > Productividad |
Depósito de Usuario: | Phd Alfredo Pasaje |
Fecha Deposito: | 04 Jun 2019 16:34 |
Ultima Modificación: | 04 Jun 2019 16:34 |
URI: | http://sired.udenar.edu.co/id/eprint/6013 |
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