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Advanced Materials Research Vols. 41-42 (2008) pp 259-264
online at http://www.scientific.net
© (2008) Trans Tech Publications, Switzerland
All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of the
publisher: Trans Tech Publications Ltd, Switzerland, www.ttp.net. (ID: 203.196.32.123-31/03/08,15:20:37)