14 madkour 335-345

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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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

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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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