(19)

(11)

EP 0 803 072 A2

(12)

(43) Date of publication: 29.10.1997 Bulletin 1997/44 (21) Application number: 96902584.0 (22) Date of filing: 11.01.1996

(51) International Patent Classification (IPC):  G01N 23/ 02( . ) (86) International application number: PCT/US1996/000045 (87) International publication number: WO 1996/022550 (25.07.1996 Gazette 1996/34)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB IT LI MC NL (30) Priority: 12.01.1995 US 19950371690 (71) Applicant: LOCKHEED MARTIN ENERGY SYSTEMS, INC. Oak Ridge, TN 37831-8243 (US)	(72) Inventors: HENSLEY, David, C. Oak Ridge, TN 37830 (US) SCHULTZ, Frederick, J. Knoxville, TN 37932 (US) PIERCE, Larry, A. Kingston, TN 37763 (US) COFFEY, Don, E. Cleveland, TN 37312 (US) (74) Representative: Pratt, Richard Wilson  D. Young & Co, 21 New Fetter Lane London EC4A 1DA London EC4A 1DA (GB)