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1.
The Raman spectroscopic studies of two rare earth trihydrides: Y H3, HoH3, have been performed in the pressure range from ambient up to 16 GPa and 25 GPa respectively. For the first time samples of REH3 in the form of powder have been studied by Raman spectroscopy using the Diamond Anvil Cell (DAC) technique. A rapid decrease of Raman activity has been observed for the hydrides under pressure values in the vicinity of structural phase transition. Metallization as a possible reason for the observed dramatic change of the REH3 Raman activity has been discussed. 相似文献
2.
F. Crisciani R. Purini 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,31(4):571-575
The present note deals with Munk's ocean model and proposes an alternative approach to find its solution, with special regard
to the western boundary layer. We introduce a suitable “distance” between the related Sverdrup streamfunction and all the
admissible streamfunctions which are valid in the western boundary layer. We prove that such distance has a minimum that singles
out a unique solution. Unlike the traditional method, this procedure works without assuming a priori any dynamic boundary
condition.
Received 16 July 2002 Published online 6 March 2003
RID="a"
ID="a"e-mail: fulcri@itt.ts.cnr.it 相似文献
3.
C. Giusti F. D. Pacati M. Schwamb S. Boffi 《The European Physical Journal A - Hadrons and Nuclei》2007,33(1):29-38
Results for the cross-sections of the exclusive 16O(e, e'pn)14N and 16O(γ, pn)14N knockout reactions are presented and discussed in different kinematics. In comparison with earlier work, a complete treatment
of the center-of-mass (CM) effects in the nuclear one-body current is considered in connection with the problem of the lack
of orthogonality between initial bound and final scattering states. The effects due to CM and orthogonalization are investigated
in combination with different treatments of correlations in the two-nucleon overlap function and for different parametrizations
of the two-body currents. The CM effects lead in super-parallel kinematics to a dramatic increase of the 16O(e, e'pn) cross-section to the 12
+ excited state (3.95MeV) of 14N . In all the situations considered the results are very sensitive to the treatment of correlations. A crucial role is played
by tensor correlations, but also the contribution of long-range correlations is important. 相似文献
4.
5.
Intense Green Upconversion Luminescence in Er^3+:Yb^3+ Codoped Fluorophosphate Glass Ceramic Containing SrTe5O11 Nanocrystals 下载免费PDF全文
Er^3+ :Yb^3+ codoped tellurite-fluorophosphate (TFP) glass ceramic exhibits much stronger upconversion luminescence. The intensity of the 540nm green light and 651 nm red light of the TFP glass ceramic is 120 times and 44 times stronger than that of the fluorophospahte (FP) glass, respectively. XRD analysis shows that the nanocrystal in TFP glass ceramic is SrTe5O11. TFP glass ceramic also displays much higher upconversion fluorescence lifetime and crystallization stability. The narrow and strong peak at 540nm is very ideal for practical upconversion luminescence realization. This work is a new trial for exploring non-PbF2 involved nanocrystal upconversion glass ceramics. 相似文献
6.
M. Schwamb S. Boffi C. Giusti F.D. Pacati 《The European Physical Journal A - Hadrons and Nuclei》2003,17(1):7-10
The influence of the mutual interaction between the two outgoing nucleons (NN-FSI) in the 16O(e, e'pp) reaction has been investigated. Results for various kinematics are discussed. In general, the effect of NN-FSI depends on
kinematics and the chosen final state in the excitation spectrum of 14C.
Received: 19 December 2002 / Accepted: 6 February 2003 / Published online: 15 April 2003 相似文献
7.
S.A. Emelyanov 《Solid State Communications》2005,133(10):675-680
We have directly demonstrated that homogeneous photoexcitation of a quantum well in presence of uniform tilted magnetic field gives rise to a set of bypass in-plane electric currents of a different value which may flow even in the opposite directions simultaneously. The effect has been observed in an asymmetric InAs quantum well under the Landau quantization. Theoretical model of the effect are discussed as well as the related problems. 相似文献
8.
D. Andreasi S. Quaglioni V. D. Efros W. Leidemann G. Orlandini 《The European Physical Journal A - Hadrons and Nuclei》2006,27(1):47-52
The two-body knock-out reaction 4He(e, e'd )d is calculated at various momentum transfers. The full four-nucleon dynamics is taken into account microscopically both in
the initial and the final states. As NN interaction the central MT-I/III potential is used. The calculation shows a strong
reduction of the coincidence cross-section due to the final-state interaction. Nonetheless, the theoretical results exhibit
a considerable overestimation of the experimental cross-section at lower momentum transfer. Comparisons with other, less complete,
calculations suggest that consideration of a more realistic ground state might not be sufficient for a good agreement with
experiment, rather a more realistic final-state interaction could play an essential role. 相似文献
9.
C. Jing Z. Li H. L. Zhang J. P. Chen Y. F. Qiao S. X. Cao J. C. Zhang 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(2):193-196
This study predicts the structural behaviour of selected M2SbP compounds with the same structure as MAX phases. Zero pressure results of the lattice parameters, equilibrium volume,
and the internal parameter ZM are calculated with an error less than 3%. Band structure, total and partial density of states were calculated and show the
metallic character of these phases. Moreover we observed strong hybridising states; M d–P p, and M d–Sb p. The pressure dependence
of the volume, and the lattice parameters were studied. The stiffness of M–P, and M–Sb bonds was discussed in term of relative
length change under hydrostatic pressure. Hf2SbP present the highest bulk modulus and the unidirectional elastic modulus C33 is slightly greater than C11. 相似文献
10.
F. Crisciani 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,13(3):393-399
The effect of the time-dependent interface, separating an inertial quasi-geostrophic upper fluid layer from the quiescent
abyss, on the non-linear stability of a steady circulation that takes place in this layer is explored. The analysis resorts
to the method of Arnol'd's invariant resulting in a conditional stability criterion, which proves the stabilizing effect of
the interface with respect to the single-layer case. The uniqueness of the stable basic flow field follows. Finally, non-linear
and linear analyses are compared in the special case of a channeled flow with a fluctuating interface, the latter leading
to an unconditional stability statement, whose meaning is clarified by resorting to the previously obtained nonlinear criterion.
Received 8 June 2000 and Received in final form 18 September 2000 相似文献