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Makins NC Ent R Chapman MS Hansen J Lee K Milner RG Nelson J Arnold RG Bosted PE Keppel CE Lung A Rock SE Spengos M Szalata ZM Tao LH White JL Coulter KP Geesaman DF Holt RJ Jackson HE Papavassiliou V Potterveld DH Zeidman B Arrington J Beise EJ Belz E Filippone BW Gao H Lorenzon W Mueller B McKeown RD O'Neill TG Epstein M Margaziotis DJ Napolitano J Kinney E Anthony PL van Bibber K Dietrich FS Gearhart RA Patratos GG Kuhn SE van den Brand JF Bulten H Jones CE 《Physical review letters》1994,72(13):1986-1989
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I. Alfter E. Bodenstedt B. Hamer J. van den Hoff W. Knichel H. Münning S. Piel R. Sajok J. Schüth 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(3):273-283
Theg-factors of the four lowest states of the ground state rotational band of158Dy have been determined asg(2 1 + )=+0.362(23),g(4 1 su+ )=+0.340(20),g(6 1 su+ )=+0.207(36) andg(8 1 su+ )=+0.21(11). Theg-factors of the 2+ and 4+ states were measured by the IPAC method with radioactive samples of 2.4 h158Er in external magnetic fields. To investigate the higher states, for the first time an on-line γ—γ IPAC experiment was performed with the reaction156Gd(α, 2n)158Dy by use of the static hyperfine field of DyGd. 相似文献
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I. Koenig E. Berdermann F. Bosch P. Kienle W. Koenig C. Kozhuharov A. Schröter H. Tsertos 《Zeitschrift für Physik A Hadrons and Nuclei》1993,346(2):153-168
We present the results obtained from a series of +–-coincidence measurements in heavy-ion collisions using the double-Orange-spectrometer at GSI. The collision systems U+U, U+Pb, and U+Ta were investigated at bombarding energies close to and slightly above (U+Ta) the Coulomb barrier. For all systems studied, very narrow (FWHM–20 keV) +– lines were observed in the sum-energy spectra, with kinetic energies ranging from 555 keV to 810 keV, superimposed on a continuous distribution mainly due to uncorrelated +– emission. Particularly in the U+Ta system, a pronounced sum-energy line appears at 634 keV, predominantly in deep-inelastic collisions. In some cases (e.g. U+Pb) the line characteristics is consistent with a two-body decay mode of an emitter which moves with the c.m. velocity of the colliding ions. However, other lines, and in particular the 634 keV line (U+Ta), exhibit a rather isotropical opening-angle distribution whereas their energy is unequally shared between positrons and electrons, thus being in clear disagreement with this scenario. In general, the data preclude an emission from the separated (moving) nuclei, and, in the latter cases, provide evidence that the e+e–-pair decay occurs in the vicinity of the Coulomb field of a third heavy (positively charged) partner having only a small transverse velocity (|v|<>Dedicated to Prof. B. Povh on the occasion of his 60th birthday 相似文献
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den Brok MW Nuijen B Miranda E Floriano P Munt S Manzanares I Beijnen JH 《Journal of chromatography. A》2003,1020(2):251-258
ES-285 x HCl [(2S,3R)-2-amino-3-octadecanol hydrochloride] is a novel investigational anticancer agent, which has shown in vitro and in vivo cytotoxic activity against various tumor cell lines with selectivity for certain solid tumors. The pharmaceutical development of ES-285 x HCl warranted the availability of an assay for the quantification and purity determination of ES-285 x HCl active pharmaceutical ingredient (API) and its pharmaceutical dosage form. A liquid chromatographic method (LC) comprising of derivatisation of ES-285 x HCl with phenylisothiocyanate and UV-detection was developed. The method was found to be linear, precise and accurate. The assay also proved selectivity as determined by analysing ES-285 x HCl in combination with 15 analogues and in combination with hydroxypropyl-beta-cyclodextrin, the excipient used in the lyophilised pharmaceutical dosage form. Stress testing showed that the degradation products were separated from the parent compound, confirming its stability indicating capacity. The method was found robust as determined with design of experiments (DoE), which made it possible to predict system suitability responses in worst case experimental conditions and to define criteria for system suitability testing. 相似文献