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Abstract  

The heat capacity of 9.70 and 11.35 mol% yttria stabilized zirconia ((ZrO2)1–x(Y2O3)x; x=0.0970, 0.1135) was measured by adiabatic calorimetry between 13 and 300 K, and some thermodynamic functions were calculated and given in a table. A large excess heat capacity extending from the lowest temperature to room temperature with a broad maximum at about 75 K was found in comparison with the heat capacity calculated from those of pure zirconia and yttria on the basis of simple additivity rule. The shape of the excess heat capacity is very similar to the Schottky anomaly, which may be attributed to a softening of lattice vibration. The amount of the excess heat capacity decreased with increasing yttria doping, while the maximum temperature did not vary. The relationships among the excess heat capacity, defect structure and interatomic force constants, and also the role of oxygen vacancy were discussed.

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Central European Geology
Authors: Arnold Gucsik, Tasuku Okumura, Hirotsugu Nishido, Ildikó Gyollai, Kiyotaka Ninagawa, Natalie Deseta, and Péter Rózsa

. Sigel , G.H. , M.J. Marrone 1981 : Photoluminescence in as-drawn and irradiated silica optical fibers: An assessment of the role of non-bridging oxygen defect centers . – Journal of Non-Crystalline Solids , 45 , pp. 235 – 247

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Journal of Thermal Analysis and Calorimetry
Authors: A. Caneiro, L. Mogni, N. Grunbaum, and F. Prado

in the computation of the mixing entropy. Thus, n equals 0 for O(1), 4 for O(1) and O(3) and 6 for O(1), O(2) and O(3). In this model both, the oxygen defects and the localized charge carriers, contribute to the partial molar entropy

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2 O and CO 2 from the sample; (4) slow decreasing of the temperature for 4 h to about 620 K; (5) filling of the oxygen defects by O 2 at 4 hPa for 8 h at 620 K; (6) gentle deoxygenation of the volume over the sample through its repeated adjunction

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Journal of Thermal Analysis and Calorimetry
Authors: A. Caneiro, L. Mogni, N. Grunbaum, and F. Prado

temperature (1173 K) under reduced environments (N 2 , CH 4 ). Furthermore, as we discussed in the previous section, the high concentration of oxygen vacancies of SrFe 0.2 Co 0.8 O 3−δ increases the electrostatic interaction among oxygen defects and, thereby

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