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71.
A new supramolecular compound,{[2-(2-pyridyl)benzimidazoleH2]2 ·[SbCl5]2-}2,was synthesized by the hydrothermal reaction of o-diaminobenzene,2-pyridinecarboxylic acid and SbCl3 in 1:1 HCl solution,and characterized by chemical analysis,elemental analysis,IR spectra,thermogravimetric analysis and fluorescence spectra. The crystal structure was deter-mined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system,space group P21/c,with a=16.0397(13),b=14.3189(12),c=15.6370(13),β=105.8980(10)°,V=3454.0(5)3,Z=4,C24H22Cl10N6Sb2,Mr=992.48,Dc=1.909 g/cm3,μ=2.366 mm-1,S=1.010,F(000)=1920,R=0.0254 and wR=0.0555. The coordination anion,[SbCl5]2-which is a distorted tetragonal pyramid,is composed by coordinating action with Sb3 ion and five adjacent chloride ions. Every four coordination anions of [SbCl5]2-form a biquaternion ring structure through the secondary bonding of Sb···Cl. Moreover,the compound adopts a three-dimensional network supramolecular structure because of the hydrogen bonds and π-π stacking between the rings and the 2-(2-pyridyl)benzimidazole divalent cations. The title compound also shows good fluorescent behaviors. 相似文献
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74.
采用溶胶法合成了TiO2-活性白土复合光催化剂,借助XRD、XPS、SEM和UV-Vis等技术对其进行了表征,并以甲基橙为模型污染物考察了合成工艺对其光催化活性的影响规律。物相结构、扫描电镜和比表面积测试结果表明,部分纳米TiO2粒子插入活性白土层间,使其层间距扩大,复合光催化剂因而具有较高的比表面积;紫外-可见吸收光谱分析表明,与纯纳米TiO2相比,复合光催化剂在其吸收带内具有更强的吸收,且吸收边发生红移;光催化实验表明,当TiO2理论负载量为66%、煅烧温度为400 ℃时,所得复合光催化剂对甲基橙的脱色及卷烟厂蒸叶废水的处理均具有较高的催化活性。 相似文献
75.
The Contribution of the Fourth Order Exchange Diagrams to The Relativistic Microscopic Optical Potential 下载免费PDF全文
The contribution of the fourth order exchange diagrams is first studied to the imaginary part of nucleon self-energy,the relativistic microscopic optical potential and the Schrodinger equivalent potential of the relativistic microscopic optical potential based on Walecka's meson-nucleon model. 相似文献
76.
The Brownian motion driven by colored noise in the harmonic oscillator potential is studied, and the "best Fokker-Planck equationn" is proposed. The analytical formulse of the second moments of coordinate and velocity are obtained. The fluctuation behavior of a system under influence of the correlation time of colored noise is discussed. 相似文献
77.
The imaginary part of the off-energy shell optical potential of a nucleon in nuclear matter, where the polarization and correlation contribution of the exchanges of the σ and ω mesons are taken into account, is derived in the framework of the relativistic meson-nucleon field theory. The second order correction of the real part of the optical potential is calculated in terms of the dispersion relation and the effective mass of a nucleon in the nuclear medium is also investigated in this paper. 相似文献
78.
The influence of quantum effects on the one-body dissipation has been studied in a Monte Carlo simulation method.The results show that the influence of quantum effects decreases and finally dissappears as the frequency and amplitude of the collective oscillation increases.The wall formula with quantum effect taken taken into account to some extent is given analytically. 相似文献
79.
The experimental data of the neutron total cross section σt,nonelastic cross section σnon and elastic scattering angular distribution σel(θ) for ten target nuclei ranging from 12C to 238U with incident energies En=20—1000MeV were used to optimize the relativistic phenomenological optical potential (RPOP) through automatic search of the best parameters by computer.In addition,a relativistic microscopic optical potential (RMOP) based on Walecka model were also used to analyze the same data and compare with the RPOP.
Through comparison between these two kinds of relativistic optical potential hints in improving both the RMOP and RPOP is indicated. 相似文献
Through comparison between these two kinds of relativistic optical potential hints in improving both the RMOP and RPOP is indicated. 相似文献
80.
In this paper, the liquid-drop model with three parameters {c, h,a} is used to describe symmetric or asymmetric fission process. The analytical expression of the effective moment of inertia is given. The inertial and frictional tensors of nucleus are evaluated by the Werner-Wheeler method. Based on a standard liquid-drop model, the Coulomb energy and surface energy are accurately calculated. The scission point of the fissioning nucleus is defined by energy criteria. The salient features of the dynamical coefficients are discussed. 相似文献