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Isomerization of B_6,B_6^- and B_6^+ clusters

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Science china Chemistry 2010年第1期53卷 202-209页

作者： WEI GongMin1,PU ZhiFeng2.ZOU Rong3,LI GuoLiang2.3 & LUO Qiong2.3 1Department of physics,Capital normal University,Beijing 100048,{2. 2.tate Key Laboratory of Explosion Science and Technology Beijing Institute of Technology,Beijing 100081,{2. 3Center for Computational Quantum Chemistry,South china normal University,Guangzhou 510631,{2. 1. Department of physics Capital Normal University Beijing 100048 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Center for Computational Quantum Chemistry South China Normal University Guangzhou 510631 China

The interconversions between isomers with the same spin multiplicity of neutral B6 and charged B6-and B6+ clusters have been investigated at the B3LYP/6-311+G level of theory,including determination of the minimum energy pathways with transition states connecting the corresponding reactants and *** dynamic calculations,2. isomers were optimized,including 11 novel *** order to further refine the energies,single-point B3LYP/6-311+G(3df) calculations were carried out on the corresponding B3LYP/6-311+G geometries of all isomers of B6,B6-and B6+ and the corresponding isomerization transition *** stability of each isomer of B6(singlet and triplet states),B6-(doublet state) and B6+(doublet state) was analyzed from both thermodynamic and dynamic viewpoints.

关键词： B6 transition state intrinsic reaction coordinate barrier height

Bloch constant of holomorphic mappings on the unit polydisk of C^n

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Science china Mathematics 2008年第4期51卷 652-659页

作者： WANG JianFei~(1+) LIU TaiShun~2.1 college of Mathematics and physics Information Engineering Zhejiang {2. University Jinhua 32.004,china 2.Department of Mathematics Huzhou Teachers college Huzhou 313000 china college of Mathematics and physics Information Engineering Zhejiang Normal University Jinhua China Department of Mathematics Huzhou Teachers College Huzhou China

In this paper,we give a definition of Bloch mappings defined in the unit polydisk D^n, which generalizes the concept of Bloch functions defined in the unit disk *** is known that Bloch theorem fails unless we have some restrictive assumption on holomorphic mappings in several complex *** shall establish the corresponding distortion theorems for subfamiliesβ(K)andβ_(loc)(K) of Bloch mappings defined in the polydisk D^n,which extend the distortion theorems of Liu and Minda to higher *** an application,we obtain lower and upper bounds of Bloch constants for various subfamilies of Bloeh mappings defined in D^*** particular,our results reduce to the classical results of Ahlfors and Landau when n=1.

关键词： Bloch constant Bloch mapping univalent ball critical point Julia lemma locally biholomorphic mapping Landau constant

Studies on the microstructure,optical and electrical properties of organic microcavity devices based on a porous silicon reflector

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Science china(Technological Sciences) 2005年第2期48卷 191-201页

作者： XIONG Zuhong1, FAN Yongliang2. ZHAN Yiqiang2. ZHANG Songtao2. DING Xunmin2.& HOU Xiaoyuan2.1. School of physics, Southwest china-{2. University, Chongqing 400715, china 2. Surface physics Laboratory (National Key Laboratory), Fudan University, Shanghai 2.0433, china 1. School of physics Southwest China-Normal University 400715 Chongqing China 2. Surface physics Laboratory (National Key Laboratory) Fudan University 200433 Shanghai China

A novel type of microcavity organic light-emitting diode based on a porous silicon distributed Bragg reflector (PS-DBR) has first been achieved and its microstructure, optical, and electrical properties have also been investigated in detail. The microcavity is made up of the central active organic multilayer sandwiched between a top silver film and a bottom PS-DBR, formed by electrochemical etching of p++-Si substrate. The field- emission scanning electron microscopy cross-section images show the nanometer-scale layered structure and flat interfaces inside the microcavity. The reflectivity (relative to an Al mirror) of the PS-DBR is up to 99%, and the stopband is about 160 nm wide. Resonant cavity mode appears as a tip in the reflectivity spectrum of the Si-based organic multilayer films, which is a symbol that the Si-based organic multilayer structure is indeed a microcavity. The peak widths of the electroluminescence (EL) spectra from the cavities emitting green and red light are greatly reduced from 85 nm and 70 nm to 8 nm and 12.nm, respectively, as compared with those measured from non-cavity structures. Note that the EL emission from the cavity devices is single-mode, and the off-resonant optical modes are highly suppressed. Moreover, increases of a factor of about 6 and 4 of the resonant peak intensity from the cavities emitting green and red light are also observed, respectively. In addition, the current-brightness-voltage characteristics and effect parameters on the lifetime of the cavity devices are also discussed. The present technique for obtaining enhanced EL emission from Si-based organic microcavity may also be another novel effective method for realizing Si-based optoelectronics device integration.

关键词： electrochemical etching, Si-based microcavity, electroluminescence, organic light-emitting diodes.

Stochastic bi-resonance induced by external noise for Ca^2. signaling in hepatocytes

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Science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1,2.HOU Zhonghuai1 & XIN Houwen1 1.Department of Chemical physics,University of Science and Technology of china,Hefei 2.002.,{2. 2.college of physics and Electronic Information,Anhui normal University,Wuhu 2.1000,{2. 1. Department of Chemical physics University of Science and Technology of China 230026 Hefei China 2. college of physics and Electronic Information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2. oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2. oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Exchange bias for ferromagnetic/antiferromagnetic bilayers with the uniaxial anisotropy being misaligned with the exchange anisotropy

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Science china(physics,Mechanics & Astronomy) 2009年第12期52卷 1885-1892页

作者： BAI YuHao1 & YUN GuoHong1,2.1 college of Physical Science and Technology,Inner Mongolia University,Hohhot 01002.,china 2.Key Laboratory of {2. and Chemistry of Functional Materials,college of {2. and Electronic Information,Inner Mongolia normal University,Hohhot 01002.,china 1. college of Physical Science and Technology Inner Mongolia University Hohhot 010021 China 2. Key Laboratory of physics and Chemistry of Functional Materials College of Physics and Electronic Information Inner Mongolia Normal University Hohhot 010022 China

Using the principle of minimal energy and S-W model,the exchange bias for ferromagnetic/antiferro-magnetic bilayers has been investigated when the uniaxial anisotropy is misaligned with the exchange anisotropy. According to the relation between the energy of the bilayer and the orientation of ferro-magnetic magnetization,it is found that the bilayer will be in the monostable state or bistable state when the external field is absent in the initial magnetization state. The monostable state or bistable state of the bilayer,which determines the angular dependence of exchange bias directly,is controlled by the competition between the exchange anisotropy and uniaxial anisotropy. When the applied field is parallel to the intrinsic easy axes and intrinsic hard axes,one of the switching fields of the hysteresis loop shows an abrupt change,while the other keep continuous by analyzing the magnetization reversal processes. Consequently,the exchange bias field and the coercivity will show a jump phenomenon. The numerical calculations indicate that both the magnitude and direction of the exchange anisotropy will significantly affect the angular dependence of exchange bias. The jump phenomenon of exchange bias is an intrinsic property of the bilayer,which is dependent on the interfacial exchange-coupling constant,the orientation of the exchange anisotropy,the thickness and uniaxial anisotropy constant of the ferromagnetic layer.

关键词： monostable state bistable state intrinstic easy axis intrinstic hard axis switching field

Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological Sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2. ZHANG Taihua1, LI Weihuo3 & WEI Bingchen3 1. State Key Laboratory of Nonlinear Mechanics (LNM), Institute of Mechanics, Chinese Academy of Sci- ences, Beijing 100080, china 2. college of {2. and Electronic Information Science, Tianjin normal University, Tianjin 300074, china 3. National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, china 1. State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. college of physics and Electronic Information Science Tianjin Normal University Tianjin 300074 China 3. National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

Lepton flavor violating Z-boson decays at GigaZ as a probe of supersymmetry

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1949-1952页

作者： YANG JinMin 1,2.1 Department of physics,Henan normal University,Xinxiang 453007,{2. 2.Institute of Theoretical physics,Chinese Academy of Sciences,Beijing 100190,{2. 1. Department of physics Henan Normal University Xinxiang 453007 China2. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China

This paper briefly reviews the lepton flavor violating Z-decays at GigaZ as a probe of supersymmetry by focusing on Z → i j in two representative supersymmetric models: the minimal supersymmetric model without R-parity and the supersymmetric seesaw *** work concludes that under the current experimental constraints from LEP and i → j γ,these rare decays can still be enhanced to reach the sensitivity of the ***,supersymmetry can be probed via these decays at GigaZ.

关键词： Z-decay GigaZ supersymmetry

Imaging theory of nonlinear second harmonic and third harmonic generations in confocal microscopy

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 8-16页

作者： TANG Zhilie1, XING Da2.& LIU Songhao2.1. Department of physics, South china {2. University, Guangzhou 510631, china 2. School for Information and Optoelectronic Science and Engineering, South china {2. University, Guangzhou 510631, china Correspondence should be addressed to Tang Zhilie (email: tangzhl@***) Received April 2., 2.03 1. Department of physics South China Normal University 510631 Guangzhou China 2. School for Information and Optoelectronic Science and Engineering South China Normal University 510631 Guangzhou China

The imaging theory of nonlinear second harmonic generation (SHG) and third harmonic generation (THG) in confocal microscopy is presented in this paper. The nonlinear effect of SHG and THG on the imaging properties of confocal microscopy has been analyzed in detail by the imaging theory. It is proved that the imaging process of SHG and THG in confocal microscopy, which is different from conventional coherent imaging or incoherent imaging, can be divided into two different processes of coherent imaging. The three-dimensional point spread functions (3D-PSF) of SHG and THG confocal microscopy are derived based on the nonlinear principles of SHG and THG. The imaging properties of SHG and THG confocal microscopy are discussed in detail according to its 3D-PSF. It is shown that the resolution of SHG and THG confocal microscopy is higher than that of single- and two-photon confocal microscopy.

关键词： second harmonic generation, third harmonic generation, confocal microscopy, three-dimensional point spread function.

The study of energy bands in nucleus ^(102.Zr

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Science china(physics,Mechanics & Astronomy) 2010年第1期53卷 106-110页

作者： DONG GuoXiang 1,2., YU ShaoYing 1,2.3 , LIU YanXin 1 , SHEN CaiWan 1,2.4 & DONG YongSheng 1,2.5I School of Science, Huzhou Teachers college, Huzhou 313000, china 2.School of Science and Information Engineering, Zhejiang {2. University, Jinhua 32.000, china 3 Institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100080, china 4 Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, china 5 Department of physics, Jining Teachers college, Jining 012.00, china 1. School of Science Huzhou Teachers College Huzhou 313000 China2. School of Science and Information Engineering Zhejiang Normal University Jinhua 321000 China3. Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China4. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China5. Department of Physics Jining Teachers College Jining 012000 China

Theoretical calculations of the energy bands in nucleus 102.Zr are carried out by taking the projected shell model approach, which has reproduced the experimental data. In addition, by analyzing band-head energies, corresponding configurations of yrast band, quasi-particle rotational bands and side bands, we have worked out the microscopic formation mechanism of axially symmetric deformation bands: The low-excitation deformation bands are attributed to the high-j intruder states 1g 7/2.and 1h 11/2.in the N=4, 5 shells; the quasi-particles in the orbit v5/2.[532., v3/2.[411] and v3/2.[413] in particular play an important role in the deformation of 102.Zr.

关键词： projected shell model yrast band quasi-particle rotational band side band