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981.
D. Kucheida F. Wagner G. Kaindl P. Kienle 《Zeitschrift für Physik A Hadrons and Nuclei》1968,216(4):346-354
The 69.6-keV level with spin 5/2? in189Os was investigated by the recoilless resonance absorption technique. Its magnetic moment was found to beμ (5/2)=(0.977±0.014)μ N. From the measured ratio of the excited and ground-state electric quadrupole moments,Q(5/2)/Q(3/2)=?0.79±0.09, the excited-state quadrupole momentQ(5/2)=?(0.72±0.11)b could be derived. TheE2/M1 mixing parameter of the 69.6-keV ground-state transition was found to beδ=+0.69±0.10. The results are interpreted in terms of two low-energy rotational bands with strong Coriolis mixing. 相似文献
982.
Numerical calculations of the line shape of the rf size effect for 0.1 mm thick potassium plates in the transmission geometry at 1.25 MHz, show that the amplitude of the fundamental resonance is proportional to exp (?1.22d/l), while that of the second resonance is proportional to exp (?0.92d/l), whered andl are the plate thickness and electron mean-free path, respectively. In the case of the fundamental, our result differs significantly from the exp (?1.57d/l) dependence usually assumed for the purpose of determiningl, and indicates that the conventional analysis leads to an overestimate ofl by approximately 30%. The amplitude dependence found here can be explained physically in terms of the finite skin depth, and in the case of the second resonance, in terms of the strength of the electric field splash at the center of the plate. 相似文献
983.
O. Fuchs R. Fresenius E. Dittrich A. Niemann A. Emr P. Buehler G. Winkhaus H. Wagner W. Stbernik G. Krall H. Zimmber K. Bobmann L. Johannsen K. H. Birr K. Henning M. Bartuek G. Peters H.-M. Lüschow und L. J. Ottendorfer 《Fresenius' Journal of Analytical Chemistry》1968,239(1):63-80
Ohne Zusammenfassung 相似文献
984.
Silvano Bozzini Patrizia Nitti Giuliana Pitacco Alessandro Pizzioli Claudio Russo 《Journal of heterocyclic chemistry》1996,33(4):1217-1221
Tricyclic compounds with an imidazolinone ring fused to 1,2- and 1,4-naphtoquinones were synthesized by a reaction of 4-amino-1,2-naphthoquinone and 2-amino-1,4-naphthoquinone with electrophilic symmetric and non symmetric diazenes. 相似文献
985.
Alessandro Bongini Roberto Camerini Mauro Panunzio Elisa Bandini Giorgio Martelli Giuseppe Spunta 《Tetrahedron: Asymmetry》1996,7(12):3485-3504
Stereocontrol in the asymmetric phosphonylation of aldehydes via organophosphorous esters has been obtained starting from chiral aldehydes. The nature of the O-protecting group is crucial to obtain, in terms of diastereoselectivity and chemical yields, the best results. An ab initio molecular orbital study on 2-silyloxy propanal and MM2 studies on 2-alkoxy propanal show the existence of stable cyclic and acyclic conformers, which are presumably responsible for the high syn diastereoselectivity observed in the addition of non-metal carrying phosphites. 相似文献
986.
The chemical state of gold in gold ores, mattes and roaster products has been studied by197Au Mössbauer spectroscopy. Gold minerals were studied in order to provide reference data for the ore spectra.57Fe Mössbauer spectroscopy was used to monitor the iron compounds always present in gold ores and to follow their transformations caused by smelting and roasting. 相似文献
987.
988.
A reversed-phase high-performance liquid chromatographic procedure was developed that accurately quantitates methylprednisolone (MP) and methylprednisolone acetate (MPA) in human plasma over the range 2.00-50.0 ng/ml. The internal standard, fluorometholone, was added to an aliquot of sodium fluoride-potassium oxalate-derived plasma. Samples were prewashed with hexane and extracted twice with methylene chloride. The extracts were dried with anhydrous sodium sulfate, centrifuged, and the organic layer separated and dried under nitrogen. The samples were reconstituted in mobile phase and washed an additional time with hexane before 100 microliters were injected onto a Beckman/Altex Ultrasphere ODS column with ultraviolet absorbance detection at 254 nm. Composition of the mobile phase was acetonitrile-water-glacial acetic acid (33:62:5, v/v/v). Calibration curves were obtained by unweighted, linear regression of peak-height ratios of MP (or MPA)/internal standard versus theoretical concentrations of MP or MPA using a Hewlett-Packard 3357 Laboratory Automation System. Extraction efficiencies for MP and MPA over the linear range were 86.4 and 84.7%, respectively. This method was successfully implemented for the analysis of specimens generated from a single-dose bioavailability and safety study for a new formulation of Depo-Medrol sterile aqueous suspension. 相似文献
989.
K. Wagner 《Mathematische Annalen》1960,141(1):49-67
Ohne Zusammenfassung 相似文献
990.
K. Wagner 《Fresenius' Journal of Analytical Chemistry》1957,154(6):445-446
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