Study of thermal currents in powder β-spodumene ceramics doped with Cuo, FeO and TiO 2
| Autor: | A. Shehap, W. H. Osman, H. S. Ragab, R. A. Abd Ellah, F. H. Abd El-Kader, M. S. Abo Ellil |
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| Rok vydání: | 2002 |
| Předmět: |
Arrhenius equation
Chemistry Analytical chemistry Mineralogy General Chemistry Activation energy Atmospheric temperature range Condensed Matter Physics Thermal conduction symbols.namesake Electrical resistivity and conductivity visual_art symbols visual_art.visual_art_medium Relaxation (physics) Ionic conductivity General Materials Science Ceramic |
| Zdroj: | Journal of Physics and Chemistry of Solids. 63:1839-1847 |
| ISSN: | 0022-3697 |
| DOI: | 10.1016/s0022-3697(02)00166-x |
| Popis: | Ternary-phase ceramic system of Li 2 O Al 2 O 3 4SiO 2 doped with CuO, FeO and TiO 2 has been prepared and subjected to dc electrical conductivity and thermally stimulated depolarization current (TSDC) measurements as a function of temperature (30–250 °C) and field strength. The electrical conductivity results are explained by assuming both ionic and electronic conduction mechanisms coexist with different contributions over the whole temperature range of experiments. TSDC spectra have been found to be characterized by a broad intense relaxation peak, which can be attributed to an ionic charge polarization. The broad relaxation transitions are apparently a result of the nonuniform nature of this process. Activation energies are calculated for both dc electrical conductivity and TSDC according to Arrhenius equation and initial rise method, respectively. |
| Databáze: | OpenAIRE |
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