GC Condition: Column: DB-1 (100% -polydimethylsiloxane), Length: 30m; I.D.: 0.25 mm; Film: 1.0 m; Injection temp.: 250 °CDetector(FID) temp.: 275 °C; Column Temp.:80 °C initial, programmed at 10 ° C/min. to 250 °C; hold for 15 min. Sample: 0.2 l in CH2Cl2