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61.
M. Sainath K. Venkataramaniah P. C. Sood 《The European Physical Journal A - Hadrons and Nuclei》2007,31(2):135-140
Low-lying two-quasiparticle bandhead energies for the Z = 99 odd-odd nucleus 254Es are evaluated using a simple phenomenological model with the inclusion of the residual p-n interaction. Configurations of the intrinsic levels directly fed in 254Es from the parent 258Md are discussed in the light of this model. Our analysis predicts the occurrence of ten K≤5 bandheads in 254Es with excitation energies E
x≤300keV. Structures of these as yet unidentified low-lying intrinsic levels and their expected locations are discussed in
the light of available experimental information. 相似文献
62.
J. Khuyagbaatar S. Hofmann F. P. Heßberger D. Ackermann S. Antalic H. G. Burkhard S. Heinz B. Kindler A. F. Lisetskiy B. Lommel R. Mann K. Nishio H. J. Schött B. Sulignano 《The European Physical Journal A - Hadrons and Nuclei》2007,34(4):355-361
Isomeric states in 214Th and 213Th were identified by means of γ -rays measured in delayed coincidence with the implanted evaporation residues. These were
produced in irradiations of 164Dy with 54Cr projectiles and separated in-flight by the velocity filter SHIP. An isomeric state of I
π = 8+ with a half-life of (1.24±0.12) μs was identified in 214Th . The configuration π[1h
9/2 ⊗ 2f
7/2] was assigned to this state. An isomeric state with a half-life of (1.4±0.4) μs was observed in 213Th . Tentatively it was assigned to an I
π = 13/2+ state. 相似文献
63.
A previous publication1 utilizing the INDO2 and CND0/23 semi-empirical SCF-MO techniques has shown that these methods predict anomalous minima in the potential surfaces of small molecules and molecular ions, particularly those of type 0-X-0. Two studies have bcmen published concerning the removal of such anomalous pre-dictiors. The first approach4 involved reparameterization of the INDO method – specifically involving the Slater exponents α, and the bonding parameters B° of carbon and oxygen – to remove the anomalous iinimum from the potential surface of C02. It was de-monstrated that reparameterization could be used to remove the Salse minimum in this case; but only at the expense of the other predictive qualities of INDO, or with the prediction of an unreal-istically broad energy minimum – neither of which could b e con-sidered an acceptable solution. 相似文献
64.
Meiqiang Feng Xuemei Zhang Weigao Ge 《Journal of Mathematical Analysis and Applications》2008,338(2):784-792
In this paper, exact number of solutions are obtained for the one-dimensional p-Laplacian in a class of two-point boundary value problems. The interesting point is that the nonlinearity f is general form: f(u)=λg(u)+h(u). Meanwhile, some properties of the solutions are given in details. The arguments are based upon a quadrature method. 相似文献
65.
K.A. Schmidt M. Bergström G.B. Hagemann B. Herskind G. Sletten P.G. Varmette J. Domscheit H. Hübel S.W. Ødegård S. Frattini A. Bracco B. Million M.P. Carpenter R.V.F. Janssens T.L. Khoo T. Lauritsen C.J. Lister S. Siem I. Wiedenhöver D.J. Hartley L.L. Riedinger A. Maj W.C. Ma R. Terry 《The European Physical Journal A - Hadrons and Nuclei》2001,12(1):15-28
High-spin properties of the nucleus 169Hf have been studied through the fusion evaporation reaction 96Zr(76Ge,3n)169Hf at a beam energy of 310 MeV. The known rotational bands have been extended considerably and 6 new bands have been established,
four of which form coupled bands with pronounced M1 connections. Quasiparticle assignments are suggested for the new band structures, and it appears that coupling to vibrational
degrees of freedom plays a role. Both coupled bands involve the excitation of quasiprotons. In the region of highest spin,
a large alignment gain is interpreted in terms of a mixed crossing where an h
9/2 and an h
11/2 quasiproton provide the two signatures of the aligning configuration.
Received: 23 March 2001 / Accepted: 20 September 2001 相似文献
66.
红粘土的微结构及其概化模型 总被引:3,自引:0,他引:3
本文论述红粘土的物质组成和微结构特征,在此基础上提出了红粘土微结构的概化模型,并根据这种模型对红粘土的工程特性进行了探讨。 相似文献
67.
68.
C. Madhukar Reddy G.R. Dillip B. Deva Prasad Raju 《Journal of Physics and Chemistry of Solids》2011,72(12):1436-1441
Lead containing calcium zinc sodium fluoroborate (LCZSFB) glasses doped with different concentrations of trivalent dysprosium ions were prepared and investigated by the XRD, FTIR, optical absorption, photoluminescence and decay curve analysis. The experimentally determined oscillator strengths have been determined by measuring the areas under the absorption peaks and the Judd–Ofelt (J–O) intensity parameters were calculated using the least squares fit method. From the evaluated J–O parameters the radiative transition probability rates, radiative lifetimes and branching ratios were calculated for 4F9/2 excited level. Room temperature photoluminescence spectra for different concentrations of Dy3+-doped LCZSFB glasses were obtained by exciting the glass samples at 386 nm. The intensity of Dy3+ emission spectra increases with increasing concentration of 0.1, 0.25, 0.5 and 1.0 mol% and beyond 1.0 mol% the concentration quenching is observed. The measuring branching ratios are reasonably high for transitions 4F9/2→6H15/2 and 6H13/2, suggesting that the emission at 484 and 576 nm, respectively, can give rise to lasing action in the visible region. From the visible emission spectra, yellow–blue (Y/B) intensity ratios and chromaticity color coordinates were also estimated. The lifetimes of 4F9/2 metastable state for the samples with different concentrations were also measured and discussed. 相似文献
69.
Soda-lime-silicate glasses doped with different rare-earth oxides (La2O3, CeO2, Nd2O3, Gd2O3 and Y2O3) of 1 mol% content were prepared with the traditional melting-quenching methods. In order to reveal the effects of rare-earth elements on the behavior of soda-lime-silicate glass, the structure of soda-lime-silicate glasses doped with different rare-earth oxides were determined with Fourier transform infrared spectrometer using the KBr method, and viscosity of glass melts were measured by the rotating crucible viscometer, the melting temperature of the studied glasses were derived on the basis of Arrhenius Equation, moreover the density, bending strength and molar volume were measured and calculated. The effect of rare-earth dopants on the structure of soda-lime-silicate was analyzed by a shift of peak position and variation in the full-width at half-maximum. The effect of doping rare-earth oxides into glass on the viscosity, density and bending strength was interpreted by changing in structure of soda-lime-silicate glasses doped with rare-earth oxides. 相似文献
70.
H.-K. Kim E. Tuite B. Nordén B.W. Ninham 《The European physical journal. E, Soft matter》2001,4(4):411-417
The source of the activation energy that allows cutting of DNA by restriction enzymes is unclear. A systematic study of the
cutting efficiency of the type-II restriction endonuclease EcoRI, with varying background electrolyte ion pair and buffer reported here, shows only a modest dependence of efficiency on
cation type. Surprisingly, efficiency does depend strongly on the presumed indifferent anion of the background salt. What
emerges is that competition between the background salt anion and the buffer anion for the enzyme and DNA surfaces is crucial.
The results are unexpected and counterintuitive from the point of view of conventional electrolyte theory. However, taken
together with recent developments in surface chemistry, the results do fall into place and could also suggest a novel mechanism
for enzyme activity as an alternative to metal-activated hydrolysis: microscopic cavitation in a hydrophobic pocket might
be the source of activation energy.
Received 19 June 2000 and Received in final form 17 October 2000 相似文献