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61.
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A series of high-mannose and complex type glycoprotein-N-glycans was subjected to high-pH anion-exchange chromatography. The results revealed that this method represents a useful tool for analytical characterization of single oligosaccharides as well as preparative separation of complex mixtures of carbohydrate side-chains. On the other hand, it became evident that in several cases a combination of different chromatographic techniques is required for efficient separation of individual oligosaccharide species. 相似文献
63.
Winfried Geyer 《Order》1993,10(4):363-373
In this paper, we consider the following reconstruction problem: Given two ordered sets (G, ) and (M, ) representing join- and meet-irreducible elements, respectively together with three relationsJ,,
onG×M modelling comparability (gm) and maximal noncomparability with respect tog (gm, butgm*) and with respect tom (gm, butgm*). We determine necessary and sufficient conditions for the existence of a finite latticeL and injections :GJ(L) and :MM(L) such that the given order relations and the abstract relations coincide with the one induced by the latticeL. 相似文献
64.
Chemically modified steroids (designer steroids), including tetrahydrogestrinone and norbolethone, pose a threat to the integrity of the sport community. These compounds have recently been detected in urine specimens from athletes, resulting in temporary or permanent suspension from amateur and/or professional competition. Triple quadrupole mass spectrometers enable doping control laboratories to screen for unknown, anabolic, androgenic steroids utilizing precursor ion scans. On the basis of common dissociation patterns of steroids with common structural features, characteristic product ions were selected to serve as diagnostic markers for previously unidentified drugs or drug metabolites in human urine samples. An assay was established to complement standard screening procedures. Urine specimens were enzymically hydrolyzed, partitioned into ether, concentrated, and analyzed by precursor ion scanning. Spectra from samples fortified with eight standard compounds (methyltestosterone, ethyltestosterone, 1-testosterone, gestrinone, dihydrogestrinone, tetrahydrogestrinone, norbolethone, and propyltrenbolone) and one deuterium-labeled analog (d(4)-tetrahydrogestrinone) at 50 ng/ml of urine, had precursor ion peaks other than those from common endogenous steroids. Subsequent product ion scan experiments on precursor ions of peaks of unknown origin provided structural identification of the unknown compounds. 相似文献
65.
R. Geyer und G. Henze 《Fresenius' Journal of Analytical Chemistry》1960,177(3):185-190
Zusammenfassung Die kathodische Reduktion salzsaurer Wolfram(VI)-lösungen an Blei- oder Quecksilberelektroden verläuft über die 5 wertige Stufe bis zum 3 wertigen Wolfram. Wolfram(IV) tritt nicht auf. Reine Lösungen von dreiwertigem Wolfram hatten stets eine grüne Farbe; nur bei niedrigen Wolframkonzentrationen trat ein gelbgrüner Farbton hervor. Eine Reduktion über die 3 wertige Stufe hinaus konnte nicht festgestellt werden.Mit elektrolytisch hergestellten Wolfram(V)- und Wolfram(III)-lösungen führten wir Potentialmessungen an den Systemen WVI/V und WV/III in konzentriert salzsauren Lösungen durch. Es zeigte sich ein starker Einfluß der Säurekonzentration auf die Potentialwerte. 相似文献
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The Moyal product is used to cast the equation for the metric of a non-Hermitian Hamiltonian in the form of a differential equation. For Hamiltonians of the form p2+V(ix) with V polynomial this is an exact equation. Solving this equation in perturbation theory recovers known results. Explicit criteria for the hermiticity and positive definiteness of the metric are formulated on the functional level. 相似文献
69.
Lifetime of levels up to 22+, have been measured in 78Kr and an oblate shape is assigned to the ground state using the CSM and the configuration dependent shell correction calculations.
Calculations further show that 78Kr is highly γ-soft nucleus. The experimental Q
t values coupled with theoretical calculations indicate an oblate shape for 78Kr at low spins and triaxial shape at higher spins 相似文献
70.