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961.
The hydrothermal reaction of 1,2-bis(imidazol-1′-yl)ethane (Bime) and Ni(NO3)2·6H2O gave rise to a two-folded interpenetrating 3D coordination polymer, [Ni(Bime)3·(NO3)2]n. Singlecrystal X-ray diffraction analyses show that the complex crystallizes in rhombohedral space group R-3. Ni(II) lies on a crystallographic S6 centre and connects six bimes into a 3D porous network. Bime exhibits an anti conformation. NO3- locates as the void filler to balance the charge in the system. The framework is stable through the two-folded interpenetration among the building units. 相似文献
962.
Several new phases containing platinum in Y-Ba-Cu-O system are reported in this paper. When Ba-Y-Cu-O system containing platinum is sintered at 950°C, two hexagonal phases YBa2(Pt, Cu)3O9-δ and Ba4Pt1+x Cu2-x Cu2-x O9-δ (x = 0.1 – 0.9) are found, respectively. The super-K2NiF4 structure Ba x Y2-x (Cu, Pt)O4 is obtained above 1000°C in the Y-Ba-Cu-O system containing platinum. Electrical properties of these phases are also reported. 相似文献
963.
We have investigated the structure evolution of the124-134Xe isotopic chain in the framework of the proton-neutron interacting model IBM2. The positive parity spectra of the ground state, quasi-β and quasi-γ bands are reproduced well. The staggering in124-130Xe are almost completely removed and the γ band agree well with the experiment data, even for the high-spin quasi-γ states. The key quantities of the collective structure evolution, including level energies, the B(E2) transition branching ratios, and the M1 excitations to 1+1mixer-symmetry states are analyzed by comparing with the experimental data. The parameters for representation of the Oπν(6) and SU πν(3) features in isotopes are examined. Both experimental data and theoretical results show that the shape phase transition of124 134Xe isotopic chain is from the SU πν(3)(triaxial rotation) to the Uπν(5)(vibration motion) with a considerable constituent of the Oπν(6) symmetry(γ-unstable rotation), where the shape phase transition rapidly takes place between the neutron number N = 76 and N = 78. 相似文献
964.
A multireference configuration interaction(MRCI) study has been carried out on the LiCl molecule. The potential energy has been calculated over a wide range of internuclear separation for the 21 low-lying electronic states of the LiCl molecule dissociating into Li(2S,2P,3S)+Cl(2P). The(4)1Σ+,(3)1Π, 1-33Σ+, 1-33Π,1,3,1,3Σ,(5)1Σ+,(4)3Σ+,(4)1Π,(4)3Π excited states are studied for the first time in theory. Molecular spectroscopic constants(Re, De,ωe, ωeχe, Be and αe) have been derived for the 9 bound states(X1Σ+,(3)1Σ+,(2)3Σ+,1,3,1,3Σ,(4)1Π,(4)3Π) with a regular shape, and the spectroscopic constants of ground states X1Σ+are in good agreement with available experimental and theoretical values. The relative diferences between experimental values and our values for Re, De, ωe, ωeχe, Be andαe are 1.02%, 0.60%, 1.72%, 9.46%, 2.0%, and 0.75%, respectively. Moreover, vibrational levels of 9 bound states, which have not been investigated experimentally, are computed. 相似文献
965.
A small fluctuation of the photon beam position will affect the intensity and polarization characteristics of synchrotron radiation (SR) when it enters an endstation through the related beamline. In this paper, by changing the electron orbit equilibrium position in the vertical direction, we have measured the corresponding changes in the absorption strength of the SR with a gold mesh in different chopper aperture positions. It is found that for three aperture positions, the absorption intensity of the gold mesh shows a good Gaussian distribution as the photon beam position moves, while the ratio of the SR intensity passing through the upper and lower apertures shows a monotonous variation. This suggests a new method for estimating the circular polarization degree of SR originating from the bending magnet based on our current measurement. 相似文献
966.
《偏微分方程通讯》2013,38(5-6):1005-1022
Abstract The combined semi-classical and quasineutral limit in the bipolar defocusing nonlinear Schrödinger–Poisson system in the whole space is proven. The electron and current densities, defined by the solution of the Schrödinger–Poisson system, converge to the solution of the compressible Euler equation with nonlinear pressure. The corresponding Wigner function of the Schrödinger–Poisson system converges to a solution of a nonlinear Vlasov equation. The proof of these results is based on estimates of a modulated energy functional and on the Wigner measure method. 相似文献
967.
微积分看作0.9 总被引:3,自引:3,他引:0
林群 《数学的实践与认识》2013,43(7)
由一张示意图入手,把山坡分割为"微分三角形",后者的高简称微分,图中还有小缝.于是,山坡全高=微分的和+小缝的和,或变为:微分的和=全高一小缝的和.当山坡为多项式曲线,小缝的和可以精确计算,特别,可以相继取为小数,0.1,0.01,0.001,….若令全高=1,那么:微分的和=0.9,求出了!如果承认0.9=1,又有:微分的和=全高,此即微积分基本公式.谁想的到这个公式即1=0.9? 相似文献
968.
杨征 《应用数学与计算数学学报》2013,(4):415-420
利用Riccati方程映射法和变量分离法,得到了推广的(2+1)维浅水波系统的变量分离解(包括孤波解、周期波解和有理函数解).根据得到的孤波解,构造出了方程的单孤子和双孤子结构,研究了孤子的混沌行为. 相似文献
969.
利用广义代数运算,定义了一类不变凸函数和不完全向量值Lagrange函数的鞍点,研究了涉及此类函数的多目标半无限规划问题,得到了广义鞍点的必要性和充分性条件.在更弱的凸性条件下,得到了几个重要结果. 相似文献
970.
In this paper, we focus on combining the theories of fuzzy soft sets with Γ-modules, and establishing a new framework for fuzzy soft Γ-submodules. The main contributions of the paper are 3-fold. First, we present the concepts of (R, S)-bi-Γ-submodules, quasi-Γ-submodules and regular Γ-modules. Meanwhile, some illustrative examples are given to show the rationality of the definitions introduced in this paper. Second, several new kinds of generalized fuzzy soft Γ-submodules are proposed, and related properties and mutual relationships are also investigated. Third, we discover some intrinsic connections between the generalized fuzzy soft Γ-submodules presented in this paper and crisp Γ-submodules, and describe the relationships between regular Γ-modules and the generalized fuzzy soft Γ-submodules presented in this paper. 相似文献