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61.
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63.
B. J. Rendle und G. L. Franklin 《Fresenius' Journal of Analytical Chemistry》1939,118(7-8):292-293
Ohne Zusammenfassung 相似文献
64.
Roberto Beneduci James Brooke Ray Curran Franklin E. SchroeckJr. 《International Journal of Theoretical Physics》2011,50(12):3682-3696
We consider the Hamilton formulation as well as the Hamiltonian flows on a symplectic (phase) space. These symplectic spaces
are derivable from the Lie group of symmetries of the physical system considered. In Part 2 of this work, we then obtain the
Hamiltonian formalism in the Hilbert spaces of square integrable functions on the symplectic spaces so obtained. 相似文献
65.
66.
W. Dick A. Karl R. D. Evans Frau P. Curie F. Behounek W. Bothe N. E. Dorsey P. Ludewig W. A. Sokolow A. Piccard L. Meylan A. J. Allen J. A. C. Teegan A. S. Eve J. Katzmann C. L. Utterbeck D. Devaputra R. G. Franklin E. Witte H. A. Doerner und W. M. Hoskins 《Fresenius' Journal of Analytical Chemistry》1934,98(5-6):194-207
Ohne Zusammenfassung 相似文献
67.
The sodium anion of trans-1,3-dithiane-1,3-dioxide reacts with unhindered aromatic and heteroaromatic aldehydes to give adducts with 95:5 to 97:3 diastereoselectivity. 相似文献
68.
69.
Smyth WF Morgan JL O'Kane E Millar TJ Ramachandran VN 《Rapid communications in mass spectrometry : RCM》2011,25(9):1308-1314
Electrospray ionisation quadrupole time-of-flight tandem mass spectrometry (ESI-QTOF-MS/MS) has been used for characterisation of a selection of naturally occurring and synthetic coumarins from different structural classes. The product ions, suggested in earlier studies by electrospray ionisation ion trap mass spectrometry (ESI-MS(n)), are unequivocally established for the representative coumarins by virtue of accurate mass measurement. Synthetic coumarins that are unsubstituted in the heterocyclic ring give rise to a major product ion by loss of CO(2), whereas those substituted in the heterocyclic ring generally undergo alternative fragmentation releasing neutral species such as ketene or methyl ketene. Naturally occurring coumarins, unsubstituted in the heterocyclic ring and substituted in the benzene ring with chains or rings of hydrocarbons and oxygen, principally fragment at the side chain releasing unsaturated hydrocarbons. The ESI-QTOF-MS/MS behaviour of some naturally occurring and synthetic quinolines which are structurally similar or fragment similarly are included where appropriate. 相似文献
70.
Oh HB Leach FE Arungundram S Al-Mafraji K Venot A Boons GJ Amster IJ 《Journal of the American Society for Mass Spectrometry》2011,22(3):582-590
The structural characterization of glycosaminoglycan (GAG) carbohydrates by mass spectrometry has been a long-standing analytical
challenge due to the inherent heterogeneity of these biomolecules, specifically polydispersity, variability in sulfation,
and hexuronic acid stereochemistry. Recent advances in tandem mass spectrometry methods employing threshold and electron-based
ion activation have resulted in the ability to determine the location of the labile sulfate modification as well as assign
the stereochemistry of hexuronic acid residues. To facilitate the analysis of complex electron detachment dissociation (EDD)
spectra, principal component analysis (PCA) is employed to differentiate the hexuronic acid stereochemistry of four synthetic
GAG epimers whose EDD spectra are nearly identical upon visual inspection. For comparison, PCA is also applied to infrared
multiphoton dissociation spectra (IRMPD) of the examined epimers. To assess the applicability of multivariate methods in GAG
mixture analysis, PCA is utilized to identify the relative content of two epimers in a binary mixture. 相似文献