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991.
G. V. Danilyan A. M. Fedorov A. M. Gagarski F. Goennenwein P. Jesinger J. von Kalben A. Koetzle Ye. I. Korobkina I. T. Krasnoshchekova M. Mutterer V. V. Nesvizhevsky S. R. Neumaier Yu. B. Novozhilov V. S. Pavlov G. A. Petrov V. I. Petrova S. M. Solovyev W. H. Trzaska O. Zimmer 《Physics of Atomic Nuclei》2000,63(9):1671-1672
992.
M. Pinterić T. Vuletić M. Lončarić S. Tomić J.U. von Schütz 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,16(3):487-493
We report a detailed characterization of an unique 3-fold commensurate insulating state in single crystals of the organic
– inorganic d hybrid Cu(DMe-DCNQI)2 systems with deuterated and partially deuterated DCNQI ring, by means of low-frequency dielectric spectroscopy. A broad relaxation
mode of strength centred at kHz is observed in the hysteresis temperature region in which the insulating phase coexists with metallic islands. At lower
temperatures, outside the nucleation range, the relaxation narrows, approaching a Debye-like form for an overdamped response
of a system with a single degree of freedom. Both, the relaxation strength and the mean relaxation time () are much larger than that expected for single-particle excitations. These features suggest the origin of the dielectric
relaxation as an intrinsic property of the N = 3 charge density wave state.
Received 1 December 1999 and Received in final form 5 April 2000 相似文献
993.
S. von Rotz M.P. Locher V.E. Markushin 《The European Physical Journal A - Hadrons and Nuclei》2000,7(2):261-269
We evaluate three meson doorway mechanisms for nucleon-antinucleon annihilation at rest for the first time. Detailed results
are presented for the final state φπ0 originating from the 3S1 initial state and for the φρ channel originating from 1S0. The results presented also include the improved contributions from two meson doorway states and from the tree diagrams.
For all the channels considered a consistent explanation of large and small OZI violations emerges.
Received: 22 December 1999 相似文献
994.
T. von Egidy P. Figuera J. Galin F. Goldenbaum Ye. S. Golubeva M. Hasinoff D. Hilscher A. S. Iljinov U. Jahnke M. Krause W. Kurcewicz X. Ledoux B. Lott L. Maier M. Manrique de Lara G. Pausch L. Pienkowski B. Quednau W. Schott W. U. Schröder J. Tõke 《The European Physical Journal A - Hadrons and Nuclei》2000,8(2):197-204
Inclusive neutron energy spectra were measured by time of flight using 1.22 GeV antiprotons from LEAR, CERN, as projectiles
and targets from natural Al, Cu, Ag, Ho, Ta, Au, Pb, Bi, U. The sum of two Maxwellian distributions was fitted to the spectra
obtained at several forward and backward angles yielding neutron multiplicities Mi and slope or temperature parameters T
i for the low-energy (evaporative, i=1) and high-energy (pre-equilibrium,i=2) parts, respectively. M
1 increases with A, proportional to the nuclear volume, and M
2 is growing with A
, proportional to the nuclear radius. The T parameters are nearly independent of A. The results are compared with previous multiplicity measurements with a neutron detector, intranuclear cascade calculations and neutron spectra from stopped antiproton annihilation on nuclei. With
the measured proton spectra also the ratio of emitted neutrons to protons was determined for Au.
Received: 25 February 2000 / Accepted: 19 May 2000 相似文献
995.
A. Derevianko W. R. Johnson V. D. Ovsyannikov V. G. Pal’chikov D. R. Plante G. von Oppen 《Journal of Experimental and Theoretical Physics》1999,88(2):272-277
We use the relativistic configuration-interaction method and the model potential method to calculate the scalar and tensor
components of the dipole polarizabilities for the excited states 1s3p
3
P
0 and 1s3p
3
P
2 of the helium atom. The calculations of the reduced matrix elements for the resonant terms in the spectral expansion of the
polarizabilities are derived using two-electron basis functions of the relativistic Hamiltonian of the atom, a Hamiltonian
that incorporates the Coulomb and Breit electron-electron interactions. We formulate a new approach to determining the parameters
of the Fuss model potential. Finally, we show that the polarizability values are sensitive to the choice of the wave functions
used in the calculations.
Zh. éksp. Teor. Fiz. 115, 494–504 (February 1999) 相似文献
996.
K. Jessen W. Andrejtscheff M. Bergström P. von Brentano A. Dewald B. Herskind H. Meise C. Schumacher G. Sletten O. Stuch D. Weißhaar I. Wiedenhöver J. Wrzesinski 《The European Physical Journal A - Hadrons and Nuclei》1999,4(1):9-10
A new high-spin isomer in 145Sm was observed by in-beam γ-ray spectroscopy with the reaction 122Sn(27Al,3np) at 127 MeV performed at the Nordball multi-detector array in Roskilde. The excitation energy of the isomer was determined
to be E
x= 11147 keV, and using the generalized centroid-shift method its half-life was found to be T
1/2= (7.4 ± 1.0) ns.
Received: 23 October 1998 相似文献
997.
I. Peter W. von Oertzen H.G. Bohlen A. Gadea B. Gebauer J. Gerl M. Kaspar I. Kozhoukharov T. Kröll M. Rejmund C. Schlegel S. Thummerer H.J. Wollersheim 《The European Physical Journal A - Hadrons and Nuclei》1999,4(4):313-317
One and two neutron transfer has been measured in the heaviest asymmetric nuclear system with semi magic nuclei showing superfluid
properties, in 206Pb+118Sn collisions at an energy well below the Coulomb barrier with scattering orbits covering the largest angles. Particle-γ coincidence
techniques using 5 Euroball-Cluster detectors (EB) combined in a set-up with the Heidelberg-Darmstadt NaI-Crystal Ball (CB)
have been used. Transfer channels are identified with EB via their known γ-decays of the lowest excited states. Using the
unique feature of the set-up with the CB, transfer to well defined final states with known quantum numbers (without feeding)
are selected using the high efficiency multiplicity filter of the CB (no second γ-ray). The data are analysed using the semiclassical approach and transfer probabilities are obtained. The enhancement
for the two-neutron transfer populating the low lying superfluid 2+ state in 120Sn (and 116Sn), while the Pb-branch is in the groundstate is deduced by comparison with the strongest single neutron transfer transition.
Large enhancements (EF ≃ 103) are observed. This is the first direct measurement of enhancement for a heavy nuclear binary system with experimentally
separated levels suggesting a strong contribution from superfluid pair transfer.
Received: 18 December 1998 / Revised version: 23 February 1999 相似文献
998.
J.M. Hughes E.I. von Nagy-Felsobuki 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(2):185-192
The electronic structure and molecular properties of helides of the form (where , Al-Ar and ) were studied using the CCSD(T) method in conjunction with the series of correlation-consistent basis sets. The highest level
of theory employed, the CCSD(T)-FC/cc-pVQZ model, was used to elucidate trends in bond lengths, dissociation energies and harmonic frequencies. The more highly
charged species were found to have shorter bond lengths than the singly charged species. The ground states of the helide cations
were often those with longer bond lengths when compared with the excited state ions.
Received: 11 May 1998 / Received in final form: 2 September 1998 相似文献
999.
The orbital deletion procedure is introduced, which is suited to quantitatively investigating the electronic delocalization effiect in earboeations and boranes. While the routine, ab initio molecular orbital methods can generate wavefunetions for real systems where all electrons are delocalized, the present orbital deletion procedure can generate wavefunctions for hypothetical reference molecules where electronic delocalization effect is deactivated. The latter wavefunetion normlly corresponds In the most stable resonance structure in terms of the resonance theory. By comparing and analyzing the delocalized and the localized wavefunetions, one can obtain a quantitative and instinct pieture to show how electronic deloealizalion inside a molecule affects the molecular structure, energy as well as other physical properties. Two examples are detailedly discussed. The first is related to the hypercoujugation of alkyl groups in carbocations and a comparison of the order of stability of carbocations is made, T 相似文献
1000.
Liu J.-S. Marison I. W. von Stockar U. 《Journal of Thermal Analysis and Calorimetry》1999,56(3):1191-1195
To meet the need for studies of anaerobic microbial and animal cell cultures involving much lower heat effects as compared
to aerobic microbial cultures, a bench scale calorimeter, Bio-RCl, has been improved for achieving a higher long-term sensitivity.
This newly improved Bio-RCl was used for heat measurement of anaerobic growth of Lactobacillus helveticus. The results showed
that the bench-scale calorimetry has powerful potential for on-line monitoring and control of anaerobic bioprocesses as well
as fundamental studies, such as stoichiometry, thermodynamics and kinetics of cellular growth.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献