Submitted on: 17 November 2002.
Revised on: 04 March 2003.
Accepted on: 18 March 2003.
___________________Chemical Bulletin of Kazakh National University
Submitted on: 03 January 2004.
Revised on: 28 January 2004.
Accepted on: 14 March 2004.
___________________Chemical Bulletin of Kazakh National University
Submitted on: 16 November 1999.
Revised on: 13 December 1999.
Accepted on: 19 January 2000.
___________________Chemical Bulletin of Kazakh National University
http://reply.papertrans.cn/1/51/5085/5085-34.png
http://reply.papertrans.cn/1/51/5085/5085-35.png
Submitted on: 29 December 2003.
Revised on: 19 April 2004.
Accepted on: 30 April 2004.
___________________Chemical Bulletin of Kazakh National University