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of 143
pro vyhledávání: '"John E, Bartmess"'
Autor:
John E. Bartmess
Publikováno v:
PATAI'S Chemistry of Functional Groups. :1-27
Publikováno v:
Rapid Communications in Mass Spectrometry. 34
Rationale Over the last ten years, helium direct analysis in real time time-of-flight mass spectrometry (He DART-TOFMS) has become an established technique in rapid screening of forensic drugs to decrease the time necessary to triage forensic drug ca
Publikováno v:
Journal of the American Society for Mass Spectrometry. 29:640-650
Nitrogen can be an inexpensive alternative to helium used by direct analysis in real time (DART), especially in consideration of the looming helium shortage. Therefore, the ionization mechanism of positive-ion N2 DART has been systematically investig
Publikováno v:
Rapid communications in mass spectrometry : RCMREFERENCES. 34(1)
Over the last ten years, helium direct analysis in real time time-of-flight mass spectrometry (He DART-TOFMS) has become an established technique in rapid screening of forensic drugs to decrease the time necessary to triage forensic drug cases, there
Publikováno v:
Chemical Physics Letters. 732:136638
The photoelectron spectra of the linear CnH2n+1O− (n = 1–9) alkoxide anions are presented, building on previous reports pertaining to n = 1–3. The vertical detachment energies (VDE) and electron affinities (EA) show a monotonic increase with ca
Autor:
Joel F. Liebman, John E. Bartmess
Publikováno v:
Structural Chemistry. 24:2035-2045
The effect on heats of formation, of conjoined or proximate functional groups which can interact via polar or resonance effects, is examined using the –CF3 group as a standard. Two metrics are applied: the difference in heat of formation of G–CF3
Autor:
John E. Bartmess, Richard M. Pagni
Publikováno v:
Chirality. 25:16-21
A theoretical investigation of the photochemistry of racemic compounds with circularly polarized light was undertaken. The exact solutions of the differential equations by numerical integration to the approximate solutions used in an earlier article
Autor:
Liguo Song, Kelsey D. Cook, Zhenqian Zhu, Mary Ellen P. McNally, John E. Bartmess, Ron M. Hoffman
Publikováno v:
Analytical Chemistry. 84:7547-7554
Although qualitative and/or semiquantitative real-time monitoring of chemical reactions have been reported with a few mass spectrometric approaches, to our knowledge, no quantitative mass spectrometric approach has been reported so far to have a cali
Publikováno v:
Rapid Communications in Mass Spectrometry. 26:1320-1328
Rationale Differentiation of underivatized monosaccharides is essential in the structural elucidation of oligosaccharides which are closely involved in many life processes. So far, such differentiation has been usually achieved by electrospray ioniza
Publikováno v:
Tetrahedron. 67:9265-9272
A method for appending the ascorbyl moiety onto the framework of phenolic natural products has been developed. This reaction proceeds in two steps from l -ascorbic acid and employs acetic acid catalysis. Excellent stereoselectivity is observed during