Submitted on: 24 May 2002.
Revised on: 27 July 2002.
Accepted on: 05 September 2002.
___________________Applied Radiation and Isotopes
Submitted on: 17 August 2001.
Revised on: 13 October 2001.
Accepted on: 27 November 2001.
___________________Applied Radiation and Isotopes
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Submitted on: 25 June 2005.
Revised on: 21 October 2005.
Accepted on: 10 November 2005.
___________________Applied Radiation and Isotopes
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