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D. Bonatsos A. I. Kuleff J. Maruani P. P. Raychev P. A. Terziev 《International journal of quantum chemistry》2002,89(4):377-388
Strutinsky's standard averaging method is applied to metal clusters described by two different potentials—Clemenger–Nilsson (CN) and q‐deformed 3‐D (Q3D) harmonic oscillator (HO). In addition, a new approximate fitting formula—of the liquid drop model type—is derived for the smooth part of the energy. The results obtained for the oscillating part of the energy (shell correction term) with the two cluster potentials through the two averaging methods are compared and discussed. It is found that with both CN and Q3D HO potentials the standard and approximate methods give similar results for clusters with a large number of particles, whereas for smaller clusters significant differences appear. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 相似文献
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D. Bonatsos D. Lenis N. Minkov P. P. Raychev P. A. Terziev 《Physics of Atomic Nuclei》2004,67(10):1767-1775
The E(5) symmetry describes nuclei related to the U(5)-SO(6) phase transition, while the X(5) symmetry is related to the U(5)-SU(3) phase transition. First, a chain of potentials interpolating between the U(5) symmetry of the five-dimensional harmonic oscillator and the E(5) symmetry is considered. Parameter-independent predictions for the spectra and B(E2) values of nuclei with R4 = E(4)/E(2) ratios of 2.093, 2.135, and 2.157 (compared to the ratio of 2.000 of the U(5) case and the ratio of 2.199 of the E(5) case) are derived numerically and compared to existing experimental data, suggesting several new experiments. TheX(5) symmetry describes nuclei characterized byR4=2.904.Using the same separation of variables of the original Bohr Hamiltonian as in X(5), an exactly soluble model with R4=2.646 is constructed and its parameter-independent predictions are compared to existing spectra and B(E2) values. In addition, a chain of potentials interpolating between this new model and the X(5) symmetry is considered. Parameter-independent predictions for the spectra and B(E2) values of nuclei with R4 ratios of 2.769, 2.824, and 2.852 are derived numerically and compared to existing experimental data, suggesting several new experiments. 相似文献
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In this work we present a matrix analysis of the sensitivity of otherwise dispersionless 4f and 2f-2f optical systems to misalignments resulting in spatio-temporal distortions of ultrashort laser pulses. Special attention is given to the possible creation of a pulse-front tilt (PFT). The exact analytical expression for the second-harmonic interferometric autocorrelation signal of an inverted-field autocorrelator is calculated. It confirms the effective broadening of the ultrashort pulses in the presence of an arbitrary PFT. 相似文献
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In this paper we use the approach introduced in (Goerss et al., Ann Math 162(2):777–822, 2005) in order to analyze the homotopy groups of $L_{K(2)}V(0)$ , the mod- $3$ Moore spectrum $V(0)$ localized with respect to Morava $K$ -theory $K(2)$ . These homotopy groups have already been calculated by Shimomura (J Math Soc Japan 52(1): 65–90, 2000). The results are very complicated so that an independent verification via an alternative approach is of interest. In fact, we end up with a result which is more precise and also differs in some of its details from that of Shimomura (J Math Soc Japan 52(1): 65–90, 2000). An additional bonus of our approach is that it breaks up the result into smaller and more digestible chunks which are related to the $K(2)$ -localization of the spectrum $TMF$ of topological modular forms and related spectra. Even more, the Adams–Novikov differentials for $L_{K(2)}V(0)$ can be read off from those for $TMF$ . 相似文献
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Magnetic behavior of Fe atoms in YBa2(Cu1−x
Fe
x
)3O
y
system in superconducting (SC) and non-SC states is studied. In SC region one magnetic ordering point Tm1 is observed for all Fe atoms in Cu1 sites: Tm1=10 K and 16 K for x=0.05 and x=0.10, respectively. In the non-SC state for x=0.05 Cu1 and Cu2 sublattices are magnetically
independent and two magnetic ordering points are found: Tm1=20 K and Tm2=405K. For x=0.10 a strong magnetic interaction between Cu1 and Cu2 sublattices appears and only one ordering point Tm2=435 K is observed. 相似文献
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New results on the Mossbauer spectroscopy of the YBa2(Cu1−xFex)3Oy system are reported and the availible reliable experimental data are briefly summarized. 相似文献
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D. Barb S. Constantinescu D. Tarina I. S. Lyubutin B. V. Mill V. G. Terziev T. D. Dmitrieva A. V. Butashin 《Hyperfine Interactions》1989,46(1-4):645-650
Western Canadian cretaceous coal (WC5) and Appalachian carboniferous coal (AC4) are good coking coals, although their rheological properties predict a different behaviour with this respect. According to Mössbauer Spectroscopy, iron-based mineral matters of these coals are very different: WC5 spectrum exhibits chiefly Fe3O4 while AC4 contains mainly ferrous silicate and no ferric ion. However the spectra of the ashes exhibit a similarity: they characterize α-Fe2O3 with a distribution of particle sizes extended down to some tens of nanometers. Such a dispersion could favour catalytic processes during the low temperature stages of coking. 相似文献