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Loutfy H. Madkour
335
Journal of the University of Chemical Technology and Metallurgy, 45, 3, 2010, 335-346
SEMICONDUCTIVITY BEHAVIOUR OF EGYPTIAN NATURAL SINTERED OREFOR THERMOTECHNOLOGICAL APPLICATIONS
Loutfy H. Madkour
Chemistry Department, Faculty of Sciences and Arts,
Al-Kamil, King Abdul-Aziz University,
P.O. Box 80207 Jeddah 21589,
Kingdom of Saudi Arabia
E-mail: loutfy.madkour@yahoo.com
lmadkour@kau.edu.sa
ABSTRACT
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Received 05 May 2009
Accepted 22 July 2010
INTRODUCTION
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EXPERIMENTAL
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Fig. 1. Essential electric circuit.
Fig. 2. Cross-section of the apparatus used for thermalmeasurements.
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RESULTS AND DISCUSSION
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Fig. 3. Thermal analysis of: (a) the native ore sample, (b)sintered ore samples for 4 h at 573 K (B), 773 K (C), 973 K(D) and 1273 K (E).
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Fig. 4. X-ray diffraction pattern for the native ore sample(A) and sintered ore samples for 4 hrs. at 573 K (B), 773 K(C), 973 K (D), and 1273 K (E).
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Fig. 5. Infrared spectra of the native ore sample (A) andsintered ore samples for 4 hrs. at 573 K (B), 773 K (C), 973 K(D) and 1273 K (E).
Fig. 6. Effect of sintering temperature Ts on the bulk density
Db and shrinkage (% S) of the ore samples.
Fig. 7. D.C. current voltage characteristic of sintered oresamples.
Journal of the University of Chemical Technology and Metallurgy, 45, 3, 2010
340
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Fig. 8. Logarithmic current voltage characteristic of sintered ore samples.
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Fig. 9. Temperature dependence of electrical conductivitys for sintered ore samples.
Fig. 10. Effect of sintering temperature on the activationenergy Ea for electrical conductivity of the ore samples.
Journal of the University of Chemical Technology and Metallurgy, 45, 3, 2010
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Journal of the University of Chemical Technology and Metallurgy, 45, 3, 2010
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REFERENCES
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