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Analytical Chemistry
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Common Fragments; Molecular Ion Peak Characteristic Peaks High intensity Loss of R-groups attached to the >C=O (alpha cleavage); peak at m/z = 43 for all methyl ketones (CH3CO+); McLafferty rearrangement via beta cleavage if gamma hydrogen is present; loss of m/z = 28 (C=O) for cyclic ketones after initial alpha cleavage and McLafferty rearrangement Rather low intensity Similar to those of alcohols (-OH but higher than substituted by -SH); loss of m/z that of = 45 (CHS) and m/z = 44 (CS) for corresponding aromatic thiols alcohol M+1 ion may appear (especially at Unlikely to be higher pressures); M-1 peak is detected except in case of acetonitrile weak but detectable (R- CH=C=N+); base peak at m/z = (CH3CN) and propionitrile 41 (CH2=C=N+H); McLafferty (C2H5CN) rearrangement possible; loss of HCN is case of cyanobenzenes Absent (or very Base peak at m/z = 30 (NO+); large peak at m/z = 60 (CH2=O+NO) in weak at best) all unbranched nitrites at the alpha carbon; absence of m/z = 46 permits differentiation from nitro compounds Seldom observed Loss of 30 (NO); subsequent loss of CO (in case of aromatic nitro- compounds); loss of NO2, m/z = 46, from molecular ion peak High intensity Similar to sulfoxides; loss of mass equal to RSO2; aromatic heterocycles show peaks at M-32 (sulfur), M-48 (SO), M-64 (SO2) High intensity Loss of 17 (OH); loss of alkene (m/z equal to RSOH+.); peak at m/z = 63 (CH2=SOH)+; aromatic sulfoxides show peak at m/z = 125 (+S- CH=CHCH=CHCHC=O), 97(C5H5S+), 93(C6H5O); aromatic heterocycles show peaks at M-16 (oxygen), M-29(COH); M-48(SO)
Identification of diluent degradation products in radiolyzed PUREX solvent
Published in Solvent Extraction and Ion Exchange, 2018
Satyabrata Mishra, Anil Kumar Soda, Madabhushi Sridhar, C Mallika, N. K Pandey, U. Kamachi Mudali
GCMS analysis using HP1 capillary column revealed that F4 was a mixture of four compounds and mass spectral data indicated that the four compounds were isomers of nitrododecane. The 1H NMR spectrum of F4 (Figure 5) exhibited a broad multiplet signal at 4.55 ppm, which is the characteristic absorption signal of proton present in CHNO2 functionality. In contrast to F2, the individual isomers present in F4 could not be identified by GCMS analysis, as nitrododecane isomers did not generate characteristic fragmentation pattern through alpha cleavage in their mass spectra.