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51.
Zhi-Yong Jiao Jun-Mao Ma Ning Li Xia Fu 《International Journal of Theoretical Physics》2008,47(11):2841-2849
In this paper, we investigate entropy properties of the single-mode binomial field interacting with the two entangled two-level
atoms. It is found that the different initial conditions lead to the different evolutions of entropy of the binomial field. 相似文献
52.
Jiang ZY Zhang XM Zhou J Zhang FX Chen JJ Lü Y Wu L Zheng QT 《Chemical & pharmaceutical bulletin》2007,55(6):905-907
Two new sesquiterpenoids named alismorientols A (1) and B (2) were isolated from the rhizomes of Alisma orientalis collected in Sichuan province, People's Republic of China. Their structures were elucidated based on spectroscopic analyses (1D and 2D NMR data including HSQC, HMBC, COSY, and ROESY) and X-ray crystallographic analysis. Anti-hepatitis B virus (HBV) bioassay revealed that compound 1 showed moderate anti-HBV activity in vitro with IC50 for HBsAg: 1.1 microM, for HBeAg: 14.7 microM. 相似文献
53.
Entrance Channel Dependence of the Correlation Function of IMFs in 36Ar+112,124Sn at 35MeV/u 下载免费PDF全文
HU Rong-Jiang XIAO Zhi-Gang WU He-Yu DUAN Li-Min WANG Hong-Wei YUAN Xiao-Hua JIN Gen-Ming ZHU Yong-Tai LI Zu-Yu WANG Su-Fang XU Hu-Shan ZHANG Bao-Guo WEI Zhi-Yong FENG Zhao-Qing FU Fen 《中国物理C(英文版)》2007,31(4):350-356
The reduced velocity correlation functions of the Intermediate Mass Fragments (IMFs) were measured in the reactions of 36Ar+112,124Sn at 35MeV/u. The anti-correlation at small reduced velocities is more pronounced in 36Ar+124Sn system than that in 36Ar+112Sn system. The difference of the correlation functions between the two reactions is mainly contributed by the particle pairs with high momenta. A three-body Coulomb repulsive trajectory code (MENEKA) is employed to calculate the emission time scale of IMFs for the both systems. The time scale is 150fm/c in the 36Ar+112Sn system and 120fm/c in the 36Ar+124Sn system, respectively. A calculation based on an Isospin dependence Quantum Molecular Dynamics code (IQMD) reveals that the emission time spectrum of IMFs is shifted slightly leftwards in 36Ar+124Sn compared with that in the 36Ar+112Sn system, indicating a shorter emission time scale. Correspondingly, the central density of the hot nuclei decreases faster in 36Ar+124Sn than in 36Ar+112Sn. 相似文献
54.
Via the proper-time eigenstates (event states) instead of the proper-mass eigenstates (particle states), free-motion time-of-arrival theory for massive spin-1/2 particles is developed at the level of quantum field theory. The approach is based on a position-momentum dual formalism. Within the framework of field quantization, the total time-of-arrival is the sum of the single event-of-arrival contributions, and contains zero-point quantum fluctuations because the clocks under consideration follow the laws of quantum mechanics. 相似文献
55.
In this paper, we have studied the atomic population difference and the atomic tunneling current of twocomponent Bose-Einstein condensates with a coupling drive. It is found that when the two-component Bose-Einstein condensates are initially in the coherent states, the atomic population difference may exhibit the step structure, in which the numbers of the step increase with the decrease of the Rabi frequency and with the increment of the initial phase difference. The atomic population difference may exhibit collapses, and revivals, in which their periods are affected dramatically by the Rabi frequency and the initial phase difference. The atomic tunneling current may exhibit damping oscillation behaviors, and exist the step structure for the time range of 10-10 ~ 10-9 second. 相似文献
56.
Jin-Ju Nie Yan-Tuan Li Xiao-Wen Li Zhi-Yong Wu Cui-Wei Yan 《Transition Metal Chemistry》2011,36(4):341-349
Two tetranuclear copper(II) complexes bridged by asymmetrical N,N′-bis(substituted)oxamides have been synthesized and characterized as [Cu4(dmapob)2(Me2bpy)2](pic)2·6H2O (1) and [Cu4(oxbe)2(dabt)2](pic)2 (2), where H3dmapob and H3oxbe denote N-benzoato-N′-[3-(dimethylamino)propyl]oxamido and N-benzoato-N′-(2-aminoethyl)oxamide, respectively; and Me2bpy, dabt, and pic represent 4,4′-dimethyl-2,2′-bipyridine 2,2′-diamino-4,4′-bithiazole, and 2,4,6-trinitrophenol, respectively.
Complex 1 was characterized by elemental analyses, IR and electronic spectra, and single-crystal X-ray diffraction. Its structure consists
of two asymmetrical binuclear copper(II) units linked by carboxyl bridges into a circular tetranuclear copper(II) complex
with an embedded center of inversion. The copper(II) centers are in square-planar and distorted square-pyramidal environments.
Hydrogen bonds and aromatic stacking interactions link the tetranuclear copper(II) fragments into a 3D supramolecular structure.
The interactions of complexes 1 and 2 with herring sperm DNA (HS-DNA) were investigated by electronic and fluorescence spectra and viscosity measurements. Both
complexes bind to HS-DNA via the intercalative mode, and complex 2 displays a significant binding propensity to HS-DNA. 相似文献
57.
Ben-Mei Wei Zhi-Yong Zhang Zhi-Qun Dai Kai-Cheng Zhang 《Monatshefte für Chemie / Chemical Monthly》2011,57(1):1029-1033
Abstract
Dealkylation of esters to carboxylic acids was performed using chloroaluminate ionic liquids (PyHBr/AlCl3, PyHCl/AlCl3, Me3NHCl/AlCl3, Et3NHCl/AlCl3) as catalyst and medium. The catalytic activity of PyHBr/AlCl3 (X(AlCl3) = 0.67) proved to be superior to the other three ionic liquids for the dealkylation of methyl benzoate with a conversion of 97% after 3 h at 140 °C. After easy separation from the products the ionic liquid PyHBr/AlCl3 could be reused six times without loss of its activity. 相似文献58.
Catalytic asymmetric 1,3-dipolar cycloaddition of various azomethine ylides with diethyl 2-(3,3-diphenylpropa-1,2-dienylidene)malonate has been developed successfully with good to excellent enantioselectivity for the effcient construction of 3-vinylidene-pyrrolidine derivatives containing a unique allene moiety. 相似文献
59.
60.
Rakesh Kumar Gupta Li Li Zhi Wang Bao-Liang Han Lei Feng Zhi-Yong Gao Chen-Ho Tung Di Sun 《Chemical science》2023,14(5):1138
Precise control over the shape and size of metal nanoclusters through anion template-driven self-assembly is one of the key scientific goals in the nanocluster community, however, it is still not understood comprehensively. In this work, we report the controllable synthesis and atomically precise structures of silver nanowheels Ag37 and Ag46, using homo (Cl− ions) and heteroanion (Cl− and CrO42− ions) template strategies, along with macrocyclic p-phenyl-thiacalix[4]arene and small iPrS− ligands. Structural analyses revealed that in Ag37, Cl− ions serve as both local and global templates, whereas CrO42− ions function as local and Cl− ions as global templates in Ag46, resulting in a pentagonal nanowheel (Ag37) and a hexagonal (Ag46) nanowheel. The larger ionic size and more negative charges of CrO42− ions than Cl− ions offer more coordination sites for the silver atoms and are believed to be the key factors that drive the nanowheel core to expand significantly. Also, by taking advantage of the deep cavity of thiacalix[4]arene with an extended phenyl group, Ag46 has been used as a host material for dye adsorption depending on the charge and size of organic dyes. The successful use of heteroanions to control the expansion of well-defined silver nanowheels fills the knowledge gap in understanding the directing role of heteroanions in dictating the shape and size of nanoclusters at the atomic level.A heteroanion self-assembly strategy for regulating the shape and expanding the size of the silver cluster from Ag37 to Ag46 with a macrocyclic (p-phenyl-thiacalix[4]arene) ligand has been presented. 相似文献