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Theoretical studies of the transport property of oligosilane

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science china Chemistry 2010年第12期53卷 2571-2580页

作者： ZHANG GuiLing 1,YUAN HongLiang 1,ZHANG Hui 1,SHANG Yan 1,SUN Miao 1,LIU Bo 1 & LI ZeSheng 2 1 college of Chemical and Environmental Engineering,Harbin university of science and {3.,Harbin 150080,china 2 State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry,jilin university,changchun 13.023.china 1. college of Chemical and Environmental Engineering Harbin University of Science and Technology Harbin 150080 China2. State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China

The transport mechanisms of four-conjugated systems were comparatively studied by combining ATK and Gaussian 03.*** was found that the charge-doped oligosilane behaved in a different way from the boron doped and phosphorus doped oligosilanes in terms of the transmission *** charge-doped oligosilane showed almost no conductivity owing to the damage of the electron transfer path by *** contrast,the boron doped and phosphorus doped oligosilanes were demonstrated to be good semiconductors and NDR behavior was observed for *** is a reasonable result after the analysis of the transmission spectra,MPSH states,energy gap,conjugation effect,and scattering effect.

关键词： theoretical study transport property oligosilane

Analysis of a kind of quantum cryptographic schemes based on secret sharing

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science china(Physics,Mechanics & Astronomy) 2009年第9期52卷 1313-1316页

作者： ZHANG XingLan1 & JI DongYao2 1 college of computer science and {3., Beijing university of {3., Beijing 100124, china 2 State Key Laboratory of Information Security, Graduate university of Chinese Academy of sciences, Beijing 100049, china college of computer science and {3. Beijing University of Technology Beijing 100124 China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China

Recently, Yang et al. proposed a kind of quantum cryptographic schemes based on secret sharing. The main idea is drawn from the case, where any n participants who share a secret K can co-operate as K does. This process can be applied to encryption, authentication, signature and so on. Unfortunately, since there is no identity authentication of the share's holder, these schemes inherit the limitation of secret sharing in practice. If some participants do not follow the protocol, the protocol would be a failure at last. Moreover, these schemes encounter another serious attack. Any two participants can co-operate to defeat the schemes by sending different shares to the parties unknown to the distributor of the secret K, such that these parties can execute the protocol as well. The attack proves that it is not enough for quantum cryptographic schemes that only the secret key is secure.

关键词： quantum identity authentication quantum secure direct communication quantum signature secret sharing

Static shape control of a flat shell structure

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吉林大学学报(工学版) 2006年第S1期 1-3页

作者： Yao Guo-feng, Zhang Lin-wen, Luo Zhi-jiu (college of Mechanical science and Engineering, jilin university, {3. 13.022, china jilin college of Traffic Profession Technique, {3. 13.021 ,china)

The eight-node and forty-DOF piezoelectric shell element were applied to shape control of a flat shell structure. By the direct and converse effects, a distributed piezoelectric sensor layer was used to monitor the shape deformation and a distributed actuator layer was used to suppresse the deflection. A finite element model was for static response of laminated shell with piezoelectric sensors/actuators was derived. The model was verified by calculating piezoelectric polymeric PVDF bimorph beam. The results are in good agreement with those obtained by theoretical analysis of Tzou and Hwang . A case study of the static shape control of a flat shell structure is presented.

关键词： piezoelectric shell element static shape control feedback control

DFT evaluation of the electronic structures and spectroscopic properties of the self-assembled [Pt_2M_4(C≡CH)_8](M=Cu,Ag) clusters

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science china Chemistry 2009年第11期52卷 1954-1960页

作者： BAI FuQuan1,XIA BaoHui1,2,ZHANG HongXing1,YANG BaoZhu1,WANG Jian1 & SUN Lei1 1 State Key Laboratory of Theoretical and Computational Chemistry,Institute of Theoretical Chemistry,jilin university,changchun 13.023.{3. 2 college of Chemistry,jilin university,changchun 13.023.{3. State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130023 China college of Chemistry Jilin University Changchun 130023 China

Electronic structures and spectroscopic properties of self-assembled [Pt2M4(C≡CH)8](M=Cu,Ag) clusters have been studied by the TD-DFT(time-dependent density functional theory) calculations with the polarizable continuum model(PCM).The ground-and excited-state structures were optimized by the DFT(density functional theory) *** calculated structures and spectroscopic properties are in agreement with the corresponding experimental *** [Pt2Ag4(C≡CH)8] clusters have two stable ground state geometries(D4 and D4h symmetry).The calculated Pt-M distances suggest only very weak *** Cu-Cu distances are larger than the van der Waals radii of two Cu atoms and the Ag-Ag distances are analogous with the sum of van der Waals radii of two Ag *** excitation,the interaction of Pt…M,Ag…Ag is strengthened,while the Cu…Cu distances are shortened but they are still larger than the sum of van der Waals radii of two Cu *** lowest-energy absorptions are at 450,3.5 and 3.5 nm and the emissions are at 611,43. and 43. nm for [Pt2Cu4(C≡CH)8],[Pt2Ag4(C≡CH)8](A) and(B),*** transitions are all perturbed by the Cu or Ag composition through the UV-Vis spectra region;therefore,there are not pure ILCT or MPtLCT characteristics(ILCT:intraligand charge transfer;MLCT:metal-to-ligand charge transfer) in absorptions of heteropolynuclear [Pt2M4(C≡CH)8] *** the emissions and the lowest-absorptions have different transition characteristics for each complex,the emissions should not come from the lowest-energy *** the M…M interactions in the excited state of [Pt2Ag4(C≡CH)8] are augmented,the emissions of [Pt2Ag4(C≡CH)8] clusters bear prominent ILCT character,which is the reason why the emission wavelengths of [Pt2Ag4(C≡CH)8] have a small hypsochromic shift relative to the emission wavelength of homoleptic [Pt(C≡CH)4]2-precursor.

关键词： electronic structures luminescence behavior heteropolynuclear complexes TDDFT

A Novel Vision Localization Method of Automated Micro-Polishing Robot

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Journal of Bionic Engineering 2009年第1期6卷 46-54页

作者： Zhao-jun Yang, Fei Chen, Ji Zhao, Xiao-jie Wucollege of Mechanical science and Engineering, jilin university, {3. 13.022, P. R. china [a]college of Mechanical science and Engineering Jilin University Changchun 130022 P. R. China

Based on photogrammetry technology,a novel localization method of micro-polishing robot,which is restricted within certain working space,is presented in this *** the basis of pinhole camera model,a new mathematical model of vision localization of automated polishing robot is *** vision localization is based on the distance-constraints of feature *** method to solve the mathematical model is *** to the characteristics of gray image,an adaptive method of automatic threshold selection based on connected components is *** center coordinate of the feature image point is resolved by bilinear interpolation gray square weighted ***,the mathematical model of testing system is verified by global localization *** experimental results show that the vision localization system in working space has high precision.

关键词： micro-polishing robot vision localization threshold segmentation distance constraint

Resonant Interaction between Atom and Large Period Quantized StandingLight Wave in a Quantized Trap

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Chinese Journal of Lasers 1997年第1期B6卷 39-42页

作者： WANG Xiaoguang Xie Chengjun LIU Xiuhuan LIU Xiaohua(Department of computer, changchun university, changchun,13.022 changchun Institute of Physics, Chinese Academy of Scieces, changchun, 13.021 Department of Physics,jilin Teacher's college, jilin, 13.011 Chungchun Univ Changchun China

A two-level atom in a quantized trap interacting with a large period quantized standing light wave is considered, an exactly solvable model is obtained. The coupling coeffiecients between the atom and the field are ti... 详细信息

关键词： quantized trap coherent state collapse and revival phenomenon

Supramolecular science: A new way to understand the matter world

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Chinese science Bulletin 2003年第15期48卷 1517-1518页

作者： ZHANG Xi & SHEN Jiacong Key Lab for Supramolecular Structure & Materials, college of Chemistry, jilin university, changchun 13.023. {3. Key Lab for Supramolecular Structure & Materials College of Chemistry Jilin University Changchun 130023 China

Explores supramolecular science as a new way for understanding the world of matter. Autonomous organization of components in supramolecular chemistry; Nature mimic as the the most significant source for supramolecular research; Construction of functional organized systems; Demand for miniaturization and high-performance properties in microelectronics.

关键词：超分子化学分子识别分子自组装超分子材料

DOUBLE Φ-FUNCTION INEQUALITY FOR NONNEGATIVE SUBMARTINGALES

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 211-216页

作者： MEI TAO(college of Mathematics and computer sciences, Wuhan {3., Wuhan 43.072, china.) LIU PEIDE(college of Mathematics and computer sciences, Wuhan {3., Wuhan 43.072, china.) college of Mathematics and computer sciences Wuhan University Wuhan 430072 China

The authors establish a kind of inequalities for nonnegative submartingales which depend on two functions　ψ and ψ, and obtain the equivalent conditions for　Φ and ψ such that this kind of inequalities holds. In t... 详细信息

关键词： Matingale Nonnegative submartingale Maximal function Φ-function inequality

Approximate merging of multiple Bézier segments

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Progress in Natural science:Materials International 2008年第6期18卷 757-762页

作者： Min Chenga,b,Guojin Wanga,* aInstitute of computer Graphics and Image Processing,Zhejiang university,Hangzhou 3.0027,china b{3. of science,Zhejiang university of technology,Hangzhou 3.003.,china Institute of computer Graphics and Image Processing Zhejiang University Hangzhou 310027 China college of science Zhejiang University of Technology Hangzhou 310032 China

This paper deals with the approximate merging problem of multiple adjacent Bézier curves with dierent degrees by a single Bézier curve,which is a frequently seen problem in *** unified matrix representation for precise merging is presented and the approx-imate merging curve is further derived based on matrix *** at the endpoints of curves is also discussed in the merging *** show that the method in this paper achieves satisfying merging results.

关键词： computer-aided geometric design Bézier curve Approximate merging Matrix representation