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991.
992.
993.
994.
995.
Nernst R Antreasyan D Aschman D Besset D Bienlein JK Bloom ED Brock I Cabenda R Cartacci A Cavalli-Sforza M Clare R Conforto G Cooper S Cowan R Coyne D de Judicibus D Edwards C Engler A Folger G Fridman A Gaiser J Gelphman D Godfrey G Heimlich FH Hofstadter R Irion J Jakubowski Z Keh S Kilian H Kirkbride I Kloiber T Koch W König AC Königsmann K Kraemer RW Lee R Leffler S Lekebusch R Lezoch P Litke AM Lockman W Lowe S Lurz B Marlow D Maschmann W Matsui T Messing F Metzger WJ Monteleoni B 《Physical review letters》1985,54(20):2195-2198
996.
LoSecco JM Bionta RM Biewitt G Bratton CB Casper D Chrysicopoulou P Claus R Cortez BG Errede S Foster GW Gajewski W Ganezer KS Goldhaber M Haines TJ Jones TW Kielczewska D Kropp WR Learned JG Lehmann E Park HS Reines F Schultz J Seidel S Shumard E Sinclair D Sobel HW Stone JL Sulak L Svoboda R van der Velde JC Wuest C 《Physical review letters》1985,54(21):2299-2301
997.
G. Münzenberg S. Hofmann H. Folger F. P. Heßberger J. Keller K. Poppensieker B. Quint W. Reisdorf K. H. Schmidt H. J. Schött P. Armbruster M. E. Leino R. Hingmann 《Zeitschrift für Physik A Hadrons and Nuclei》1985,322(2):227-235
In irradiations of207Pb and208Pb, respectively, with54Cr theα-decay of the isotopes259106,260106, and261106 could be observed for the first time. For260106 a spontaneous fission branch of (50 ?20 +30 )% was observed. The isotopes were identified by genetic relationships of α-decay after separation in-flight with the velocity filter SHIP and implantation into a position-sensitive silicon surface-barrier detector. The measured partial fission halflife of the doubly even isotope260106 of (7.2 ?2.7 +4.8 )ms exceeds the predicted values by at least a factor of 40. This result could be explained by the high shell corrections of the ground state mass, derived from the measured α-decay energies. The experimental results show evidence for an island of purely shell stabilized nuclei in the region of deformed isotopes beyond the actinides. 相似文献
998.
M. M. Abd-Elmeguid Ch. Sauer U. Köbler W. Zinn 《Zeitschrift für Physik B Condensed Matter》1985,60(2-4):239-248
X-ray diffraction,151Eu Mössbauer effect (ME) and magnetic susceptibility measurements have been performed to investigate the valence behavior and the magnetic interactions of the Eu ions in the intermetallic series Eu(Pd1–x
Au
x
)2Si2 (0x1) as a Forx>0.4 all experimental techniques are in agreement with each other and suggest a divalent 4f
7 ground state of the Eu ion. Belowx=0.4 the different methods lead to different results: while the lattice parameters and the ME isomer shift suggest an instable behavior of the valence the magnetic susceptibility proves a pure divalent 4f
7 ground state. These differences can be explained by assuming a partial extension of the 4f-shell radius such that the localized character of the 4f-electrons is preserved.Dedicated to B. Mühlschlegel on the occasion of his 60th birthday 相似文献
999.
Quench condensed Zr
x
Cu1–x
films offer a wide concentration range (0.1x0.9) for measurements of the Hall coefficientR
H
of amorphous Zr–Cu alloys.R
H
changes sign as a function of composition, from negative to positive, as the Zr concentration is increased. The sign change is observed in a narrow concentration range at aboutx=0.22, without any peculiarity of the conductivity at this crossover concentration. The Hall coefficient of the unannealed Zr-rich films is nearly independent of temperature. However, both, the values ofR
H
and of the temperature dependence ofR
H
change with a heat treatment well below the crystallization temperature. This is most obvious for the films with a composition close to the cross-over concentration.Dedicated to B. Mühlschlegel on the occasion of his 60th birthday 相似文献
1000.
An extensive investigation is made of electron correlations in the ground state of hydrocarbon molecules. This is done by starting from a semiempirical self-consistent field (SCF) calculation. The interatomic correlations are studied by means of a previously developed local approach to the correlation problem. It is demonstrated that the various contributions to the interatomic correlation energy can be described by simple analytical expressions which depend on the type of bond as well as on the bond lengths and angles. The results are easily understood in physical terms. The intraatomic correlations are obtained from an atoms in molecules type of approach as elaborated by Lievin et al. It makes use of a population analysis of the ground-state wave function as well as of calculations for the C and H atoms. We have then a very simple, and as it turns out rather accurate calculational scheme at hand. The computational times involved are of the same order as those for the fast SCF programs. As an application of the theory we have calculated the correlation energy difference between naphthalene and azulene.Dedicated to B. Mühlschlegel on the occasion of his 60th birthday 相似文献