碎片离子峰 Commonly Lost Fragments Common Stable Ions m-15 .CH3 mle =43 CH3C三0 m-17 .OH m-26 .CN m-28 H2C=CH2 mle =91 n m-29 .CH2CH3 .CHO m-31 .OCH3 0 m-35 .Cl m/e m-1 R-C=0 R m-43 CHC=0 m-45 .OCH2CH3 m-91 CH2 23:13:12 23:13:12 碎片离子峰