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101.
J. -L. Charvet R. Dayras D. Durand O. Lopez D. Cussol D. Dor L. Nalpas A. Van Lauwe C. Volant 《Nuclear Physics A》2004,730(3-4):431-447
A previous analysis of the charge (Z) correlations in the ΔZ−Z plane for 129Xe+natSn central collisions at 32 MeV/n has shown an enhancement in the production of equally sized fragments (low ΔZ) which was interpreted as an evidence for spinodal decomposition. However, the signal is weak and rises the question of the estimation of the uncorrelated yield. After a critical analysis of its robustness, we propose in this paper a new technique to build the uncorrelated yield in the charge correlation function. The application of this method to 129Xe+natSn central collision data at 32, 39, 45 and 50 MeV/n does not show any particular enhancement of the correlation function in any ΔZ bin. 相似文献
102.
The characteristic features of model potentials, effective potentials and pseudopotentials are carefully investigated. Then we justify our choice to work only with hermitian pseudopotential operators, and we develop a general non-empirical method to determine atomic pseudopotentials. In view of their numerical use for molecular calculations, these pseudopotentials are cast into semi-local forms, and their parameters are obtained by a least-squares process; tables of parameter values are given for the two first rows of the periodic system. 相似文献
103.
The Ruderman-Kittel-Kasuya-Yosida interaction in amorphous La80Au20 alloys with dilute Gd impurities
From magnetization measurements on some amorphous dilute La80?xGdxAu20 alloys with x ? 1 we have shown that the magnetic behavior follows the scaling laws of a spin-glass system, characteristic of the 1/r3 dependence of the pairwise interaction. We have also determined the strength of the Ruderman-Kittel-Kasuya-Yosida interaction V(r) = (V0cos 2kFr)/r3, to be V0 = 0.20 × 10?37 ergcm3. The corresponding value of the s-f exchange integral is |Jsf| = 0.14 eV, which is compared with values determined from other experiments. 相似文献
104.
Summary Direct reaction of K2MCl4 (M=Pt or Pd) with acetamide leads reproducibly to complexes which can be formulated as [Pt(C2H4ON)2Cl]n and Pd4(C2H4ON)7(OH)2. Analytical and spectroscopic (i.r., n.m.r. and e.p.r.) data support the existence of polynuclear structures involving bridging ligands and partially oxidized metal centres. 相似文献
105.
106.
63-Cu and 75-As quadrupole resonance results have been obtained for the tetrameric triethylarsine copper(I) halides (Cl, Br and I). Unusual behaviours of the temperature dependence of the 63-Cu and 75-As quadrupole resonance lines have been observed simultaneously. Between 77 and 300 K, the chlorine derivative undergoes two structural phase changes at 93 and 173 K, while phase transformations occur at 152 and 86 K respectively for the bromine and iodine derivatives. 相似文献
107.
Syntheses of the enantiomerically pure phytoprostanes B(1) type I and II are described starting from furfural and n-propylfuran. Key steps include the preparation of the Freimanis (+/-)-hydroxycyclopentenone and Wittig coupling using chiral phosphonium salts. 相似文献
108.
Necessary and Sufficient Conditions to be an Eigenvalue for Linearly Recurrent Dynamical Cantor Systems 总被引:2,自引:0,他引:2
Bressaud Xavier; Durand Fabien; Maass Alejandro 《Journal London Mathematical Society》2005,72(3):799-816
Necessary and sufficient conditions are given for linearly recurrentCantor dynamical systems to have measurable and continuous eigenfunctions.Also an example of a linearly recurrent system with a nontrivialKronecker factor and a trivial maximal equicontinuous factoris constructed explicitly. 相似文献
109.
M. Durand 《Nuclear Physics A》1973,201(2):313-325
The Faddeev equations for three nucleons are iterated up to third order using separable interactions: the Tabakin potential for the first order and the Yamaguchi potential for the other orders. This method is applied to the quasi-free scattering 2H(p, 2p)n and 2H(s, np)p. Apparent convergence of the rescattering series is obtained for incident lab energies and the shape and magnitude of the experimental results are thus reproduced. 相似文献
110.
We observe the anisotropy and the polarization properties of the Rayleigh scattered light for a planar smectic A texture of butoxyl benziledene-p-n anilino-acetophenone (BBAA). This scattering is attributed to static bends of the smectic layers, with wave vectors parallel to the smectic planes. This effect gives a simple method to measure the ratio of the extraordinary to the ordinary indices: ne/n0 = 1.18 at 89°C. 相似文献