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51.
Nuclear system interacting via quadrupole and octupole particle-hole forces is studied by the boson expansion technique. Energy spectra of the negative parity yrast band and the ground state band are calculated and compared with experiment for100Ru,112Cd,150Sm and150Gd. ExperimentalB(E1)/B(E2) ratios show strong hindrance for E1 transitions, and are used to deduce the static polarizability of E1 transitions.  相似文献   
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The present resonant x-ray scattering has been performed on a monoclinically split single domain of NaV(2)O(5). The observation of a critically enhanced contrast between V(4+) and V(5+) ions has led us to the unequivocal conclusion of the charge-order pattern of the low-temperature phase of NaV(2)O(5) below T(c) = 35 K. In spite of the possible four types of configuration of the zigzag-type charge-order patterns in the ab plane (A,A',B and B'), the stacking sequence along the c axis is determined as the AAA'A' type by comparison with model calculations.  相似文献   
54.
We study a square-lattice three-state Potts antiferromagnet with a staggered polarization field at finite temperature. Numerically treating the transfer matrices, we determine two phase boundaries separating the model-parameter space into three parts. We confirm that one of them belongs to the ferromagnetic three-state Potts criticality, which is in accord with a recent prediction, and another to the Ising-type; these are both corresponding to the massless renormalization-group flows stemming from the Gaussian fixed points. We also discuss a field theory to describe the latter Ising transition.  相似文献   
55.
Micrometer pixelated arrays comprised of different functional organic molecules were formed on a polymer film using a laser implantation and transfer dry processing technique. The spatial distribution of the implanted organic molecules and the extended pattern that they formed could be controlled with high resolution as determined using fluorescence microscopy. The individual molecular implant pixels had a diameter of less than 4 m. This method of molecular manipulation is both precise and reproducible and could therefore be used in many applications such as molecular devices, molecular sensors, non-linear optical devices, drug delivery and opto-electronic displays. PACS 81.05.Lg; 81.16.Mk; 81.65.Cf  相似文献   
56.
A kinetic study of peroxyoxalate chemiluminescence reactions employing 2,4,6-trichlorophenyl N-aryl-N-tosyloxamates supports the 1,2-dioxetanones still bearing the eliminating group as the key intermediates that interact with the fluorophores rather than 1,2-dioxetanedione.  相似文献   
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When A is a unital simple AF C∗-algebra and has a unique tracial state, it is shown that the crossed product of the two-sided infinite tensor product by the shift is a tracially AF C∗-algebra. A similar result is given to the crossed product of a certain non-unital two-sided infinite tensor product by the shift. Applying a far-reaching classification result of such C∗-algebras by H. Lin, we obtain an example of a one-parameter automorphism group on some AF C∗-algebra which is not approximately inner, a counter-example to the AF version of the so-called Powers-Sakai conjecture [23].  相似文献   
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A new vanadate PbCo2V2O8 was obtained through the study of PbO-CoO-V2O5 ternary system. The crystal structure was determined by Rietveld method, indicating that PbCo2V2O8 has a tetragonal structure of space group I41cd with a spiral chain along the c-axis. Magnetic properties of the titled compound were investigated by means of susceptibility, magnetization, and heat capacity measurements. The results show that PbCo2V2O8 is a quasi-one-dimensional canted antiferromagnet with Neel temperature of ∼4 K, being consistent with its crystal structure.  相似文献   
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