Alumatrane revisited: Distribution of oligomeric ions in electron impact ionization, chemical ionization and liquid secondary ion mass spectra

1995 ◽  
Vol 30 (5) ◽  
pp. 741-746 ◽  
Author(s):  
Michael G. Bartlett ◽  
Scot A. Burns ◽  
David A. Bruce ◽  
Kenneth L. Busch
Keyword(s):  
Electron Impact ◽  
Mass Spectra ◽  
Chemical Ionization ◽  
Impact Ionization ◽  
Electron Impact Ionization ◽  
Secondary Ion

Electron Impact and Chemical Ionization Mass Spectrometry of Some Butyrophenones

1977 ◽  
Vol 60 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Jos G Leferink ◽  
Robert A A Maes
Keyword(s):  
Mass Spectrometry ◽  
Electron Impact ◽  
Mass Spectra ◽  
Chemical Ionization ◽  
Impact Ionization ◽  
Electron Impact Ionization ◽  
Ionization Mass Spectrometry ◽  
Chemical Ionization Mass Spectrometry ◽  
Ionization Mass

Abstract The mass spectra of some butyrophenoncs are presented. Electron impact ionization and chemical ionization with isobutane as the reagent gas are compared. The chemical ionization spectra show the quasi molecular ion (M + H)+ to be the most abundant ion. Important fragments in the electron impact spectra are discussed for easy determination of other similar compounds.

scholarly journals Electron Impact Ionization Mass Spectra of 3-Amino 6-Chloro2-methyl Quinazolin-4-(3H)-one Derivative

2021 ◽  
pp. 1-5
Author(s):  
Osarumwense Peter Osarodion ◽  
◽  
Omotade Treasure Ejodamen ◽  
Keyword(s):  
Electron Impact ◽  
Mass Spectra ◽  
Impact Ionization ◽  
Cyclic Compound ◽  
Electron Impact Ionization ◽  
Ionization Mass ◽  
Fragmentation Pattern ◽  
Molecular Ion ◽  
Mass Spectral ◽  
Characteristic Fragmentation

Looking at the previous studies on quinazolinones derivatives, only limited information’s are available on their mass spectral along with the preparation of novel quinazolin-4-(3H)-one derivatives The condensation of Methyl-2-amino-4-Chlorobenzoate with acetic anhydride yielded the cyclic compound 2-methyl 7-Chloro-1, 3-benzo-oxazine-4-one (1) which further produce 3-Amino-2-Methyl 7-Chloro quinazolin-4(3H)-ones (2) via the reaction with hydrazine hydrate. The compounds synthesized were unequivocally confirmed by means of Infrared, Nuclear Magnetic Resonance (1H and 13C), Gas Chromatography-Mass spectrophotometry and Elemental analysis. Discussion: The molecular ion of m/z 235 fragments to give m/z 220 by loss of –NH group. The ion of m/z 220 was broken to give m/z 206 by losing CH2 group and fragment to m/z 177 by loss of HCO. This fragmented to m/z 162 by loss of –CH3 group and then m/z 136 by loss of CN group. The loss of O gave m/z 120 which fragment to give m/z 93 by loss of –HCN and finally gave m/z 65 by loss of CO group. Conclusion: The electron impact ionization mass spectra of compound 2show a weak molecular ion peak and a base peak of m/z 235resulting from a cleavage fragmentation. Compound 2 give a characteristic fragmentation pattern. From the study of the mass spectra of compound 2, it was found that the molecular ion had fragmented to the m/z 220. The final fragmentation led to ion of m/z 93 and ion of mass m/z 65, respectively

Gas-Liquid Chromatographic/Mass Spectrometric Screening Method for T-2 Toxin in Milk

1979 ◽  
Vol 62 (6) ◽  
pp. 1274-1280
Author(s):  
George J Collins ◽  
Joseph D Rosen
Keyword(s):  
Mass Spectrometry ◽  
Electron Impact ◽  
Chemical Ionization ◽  
Impact Ionization ◽  
Trimethylsilyl Ether ◽  
Screening Method ◽  
Internal Standard ◽  
Electron Impact Ionization ◽  
Gas Liquid Chromatography ◽  
Ionization Mass

Abstract A method for the analysis of T-2 toxin in milk is presented. Ethyl acetate extracts of milk samples which had been spiked with T-2 toxin were purified by thin layer chromatography and derivatized with N,O-bis(trimethylsilyl)acetamide to produce the T-2 toxin trimethylsilyl ether (T-2 toxin-TMS). N,O-bis(trimethylsilyl-d9)acetamide was used to make T-2 toxin d9-trimethylsilyl ether (T-2 toxin-d9TMS) which was added to the derivatized milk extract as an internal standard. Samples were analyzed by combined gas-liquid chromatography/mass spectrometry using either electron impact ionization or chemical ionization mass spectrometry. In electron impact ionization analyses, simultaneous monitoring of the T-2 toxin-TMS fragment ion at m/z 436 and the T-2 toxin-d9TMS fragment ion at m/z 445 gave a T-2 toxin-TMS detectability estimated at 6 μg/kg. In chemical ionization analyses, the T-2 toxin-TMS fragment ion at m/z 377 and the T-2 toxin-d9TMS fragment ion at m/z 386 were simultaneously monitored to give a T-2 toxin-TMS detectability estimated at 3 μg/kg. Average recovery was 85% at 200 μg/kg and 65% at 20 μg/kg.

Detection by mass spectrometry of hydrocarbon biradicals, pyridine and aniline in a flame ionization detector

1982 ◽  
Vol 35 (8) ◽  
pp. 1743 ◽  
Author(s):  
M Head ◽  
T McAllister
Keyword(s):  
Mass Spectrometry ◽  
Electron Impact ◽  
Aromatic Compounds ◽  
Mass Spectra ◽  
Impact Ionization ◽  
Electron Impact Ionization ◽  
Flame Ionization Detector ◽  
Ionization Detector ◽  
Flame Ionization ◽  
Reaction Zones

The mass spectra of ions of > 75 in an f.i.d.-type flame with benzene additive have shown that hitherto undetected species of formulas CllH9+ and CI3H9+ are present, which may be attributed to protonation of the biradicals C11H8 and C13H8 by H3O+. The remainder of the hydrocarbon ions present are attributable to protonation of aromatic compounds (e.g. naphthalene and indene) which have been detected previously in premixed benzeneloxygen flames by electron impact ionization. Addition of NH3 to the benzene sample suppresses all the hydrocarbon peaks of m/z > 100 but generates new peaks of m/z 80 and 94, attributable to the protonation of pyridine and aniline. Aniline may be generated by addition of NH2 radicals to benzene in the pyrolysis and reaction zones of the flame.

Fragmentation selectivity in electron impact ionization mass spectra of substituted dimethoxybenzenes

1992 ◽  
Vol 27 (6) ◽  
pp. 720-723 ◽  
Author(s):  
Hisao Nakata ◽  
Fumie Jitsukawa ◽  
Hitomi Toyama ◽  
Yuko Kato
Keyword(s):  
Electron Impact ◽  
Mass Spectra ◽  
Impact Ionization ◽  
Electron Impact Ionization ◽  
Ionization Mass
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