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81.
R. Kadono J. H. Brewer K. Chow S. R. Kreitzman Ch. Niedermayer T. M. Riseman J. W. Schneider T. Yamazaki 《Hyperfine Interactions》1994,85(1):259-264
The electric quadrupole interaction of55Mn nuclei was studied in the weakly ferromagnetic system MnSi using muon level-crossing resonance (LCR) technique. The temperature dependence of the electric field gradient (EFG) shows a critical behavior near the ferromagnetic transition temperature, indicating that the EFG due to the conduction electron is strongly correlated with the magnetic susceptibility in the itinerant electron magnetism. The temperature dependence of EFG is in reasonable agreement with the self-consistent renormalization theory developed by Moriya and coworkers.We gratefully acknowledge helpful discussion with Dr. N. Nishida. We also wish to thank Keith Hoyle and Curtis Ballard for technical support. 相似文献
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Kurt Günther Reinhold Carle Ilona Fleischhauer Stefan Merget 《Fresenius' Journal of Analytical Chemistry》1993,345(12):787-790
Summary A semi-preparative low-pressure liquid-chromatographic procedure using tribenzoylcellulose has been developed for the separation and isolation of the four -bisabolol stereoisomers. Stereochemical assignments were made by HPLC-polarimeter coupling and by using the authentical isomers. This method can be applied to the quality control of chamomile preparations, as it allows the detection of adulterations resulting from admixtures of synthetic -bisabolol. In addition, the isolation of all four -bisabolol stereoisomers from commercially available synthetic -bisabolol has been made possible. 相似文献
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Haiges R Vij A Boatz JA Schneider S Schroer T Gerken M Christe KO 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(2):508-517
The highly explosive molecules As(N(3))(3) and Sb(N(3))(3) were obtained in pure form by the reactions of the corresponding fluorides with (CH(3))(3)SiN(3) in SO(2) and purification by sublimation. The crystal structures and (14)N NMR, infrared, and Raman spectra were determined, and the results compared to ab initio second-order perturbation theory calculations. Whereas Sb(N(3))(3) possesses a propeller-shaped, pyramidal structure with perfect C(3) symmetry, the As(N(3))(3) molecule is significantly distorted from C(3) symmetry due to crystal packing effects. 相似文献
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Kammerer D Carle R Schieber A 《Rapid communications in mass spectrometry : RCM》2003,17(21):2407-2412
Anthocyanins of black carrots (Daucus carota ssp. sativus var. atrorubens Alef.) were investigated by high-performance liquid chromatography/electrospray ionization mass spectrometry. Besides the main compounds which have already been characterized in detail as cyanidin glycosides, six anthocyanins with m/z 757, 565, 595, 903, 933 and 903 were detected and unambiguously characterized as peonidin and pelargonidin glycosides, based on their fragmentation patterns. Peonidin and pelargonidin were identified after acid hydrolysis by comparison of the fragmentation patterns and retention times of the released aglycones with those of standard compounds. To the best of our knowledge this is the first report on anthocyanins in black carrots consisting of aglycones other than cyanidin. 相似文献