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Chinese Science Bulletin 1999年第19期44卷 1778-1783页

作者： SONG Daojun and YU XunCenter of Ion Beam Bioengineering, Institute of Plasma physics , Chinese Academy of Sciences , Hefei 230031, china college of Life Science , university of Science and technology of china , Hefei 230026, china Center of Ion Beam Bioengineering Institute of Plasma Physics Chinese Academy of Sciences Hefei China college of Life Science University of Science and Technology of China Hefei China

Using calcium chloride method of transfer gene as control, a new technique of transferring gene by low energy ion beam has been applied to the study of improving DMA damage repair ability of E. coli to UV-radiosensitivity. The genome DMA pieces of Deinococcus radio-durans, as 'foreign' genetic materials, were introduced into the UV-radiosensitive strains of E.

关键词： ion implantation Deinococcus radiodurans transfer gene survival rate unscheduled DNA synthesis.

PRECIPITATION AND MICROSTRUCTURE OF Cr MODIFIED Al_3Ti

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 13-20页

作者： W.H. Tian and M. Nemoto (Department of Materials physics and Chemistry, university of Science and technology Beijing, Beijing 100083, china Sasebo National college of technology, Okishin 1-1, Sasebo 857-1193, Japan) Dept. of Mat. Phys. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The microstructures of Cr modified Al3Ti containing Al2Ti and L10-AlTi precipitates have been investigated in terms of transmission electron microscopy(TEM). Fine precipitation of Al2Ti (Ga2Hf type structure) and Ll0-AlTi(Cr) occurs in Ll2-Al3Ti(Cr) by aging around 973K. The aging behavior was investigated by microhardness measurements. TEM observations reveal that plate-like Al2Ti precipitates lie on{100} planes of the Ll2-Al3Ti(Cr) matrix with the c axis of the tetragonal phase perpendicular to the thin plate. As contrast with Al2Ti precipitates, Ll0-AlTi(Cr) precipitates form thin plate and lie on {100} planes of Ll2-Al3Ti(Cr) matrix at the initial aging time and for long time aging the habit plane of the thin plate deviates from {100} plane and finally forms a kinked plate. The coherency stresses across the precipitate/matrix interface are considered to be the main factors controlling the precipitate morphology.

关键词： Age hardening Aluminum compounds Microstructure Precipitation (chemical) Titanium compounds

Shape phase transitions in nuclei:Effective order parameters and trajectories

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 88-97页

作者： ZHANG Yu1,2, HOU ZhanFeng2 & LIU YuXin2,3 1Department of physics, Liaoning normal university, Dalian 116029, china 2Department of physics and the State Key Laboratory of Nuclear physics and technology, Peking university, Beijing 100871, china 3Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 720000, china Department of physics Liaoning Normal University Dalian China Department of physics and the State Key Laboratory of Nuclear physics and technology Peking University Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

We analyze systematically the effective order parameters in nuclear shape phase transition both in experiments and in the interacting boson model. We find that energy ratios and B(E2) ratios can distinguish the first from the second-order phase transition in theory above a certain boson number N (about 50), but in experiments, only those quantities, such as E(L1+)/E(02+) and B(E2; (L+2)1 → L1)/B(E2; 21 → 01), etc., of which the monotonous transitional behavior in the second-order phase transition is broken in the first order phase transition independent of N, are qualified as the effective order parameters. By implementing the originally proposed effective order parameters and the new ones, we find that the isotones with neutron number Nn = 62 are a trajectory of the second order phase transition. In addition, we predict that the transitional behavior of isomer shifts of Xe, Ba isotopes and Nn = 62 isotones is approximately monotonous due to the finiteness of nuclear system.

关键词： nuclear shape phase transition interacting boson model effective order parameter finite particle number effect transition trajectory

Accurate studies on dissociation energies of diatomic molecules

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 611-621页

作者： SUN WeiGuo1, FAN QunChao1 & REN WeiYi1,2 1 Institute of physics, Sichuan university, Chengdu 610065, china 2 Institute of Theoretical physics, Xihua normal university, Nanchong 637002, china Institute of physics Sichuan University Chengdu China Institute of Theoretical physics Xihua Normal University Nanchong China

The molecular dissociation energies of some electronic states of hydride and N2 molecules were studied using a parameter-free analytical formula suggested in this study and the algebraic method (AM) proposed recently. The results show that the accurate AM dissociation energies DeAM agree excellently with experimental dissociation energies Deexpt, and that the dissociation energy of an electronic state such as the 23Δg state of 7Li2 whose experimental value is not available can be predicted using the new formula.

关键词： algebraic method, diatomic molecule, vibrational energy, dissociation energy

SYSTEM OF GENERALIZED VECTOR QUASI-EQUILIBRIUM PROBLEMS ON PRODUCT FC-SPACES

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Acta Mathematica Scientia 2007年第3期27卷 522-534页

作者：丁协平 college of Mathematics and Software Science Sichuan Normal University

By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equilibrium existence theorems, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are established in noncompact product FC-spaces. These results improve and generalize some recent results in literature to product FC-spaces without any convexity structure.

关键词： Maximal element generalized game equilibrium system of generalized vector quasi-equilibrium problems FC-spaces

Lyapunov exponents for continuous random transformations

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Science china Mathematics 2010年第2期53卷 413-424页

作者： ZHU YuJun & ZHANG JinLian college of Mathematics and Information Science, Hebei normal university, Shijiazhuang 050016, china college of Mathematics and Information Science Hebei Normal University Shijiazhuang China

In this paper, the concept of Lyapunov exponent is generalized to random transformations that are not necessarily differentiable. For a class of random repellers and of random hyperbolic sets obtained via small pertur... 详细信息

关键词： random transformation Lyapunov exponent multiplicative ergodic theorem random repeller random hyperbolic set

Symmetries and exact solutions of discrete nonconservative systems

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1699-1706页

作者： FU JingLi1,LI XiaoWei2,LI ChaoRong1,ZHAO WeiJia3 & CHEN BenYong4 1 Institute of Mathematical physics,Zhejiang Sci-Tech university,Hangzhou 310018,china 2 Department of physics,Shangqiu normal university,Shangqiu 476000,china 3 Department of Mathematics,Qingdao university,Qingdao 266071,china 4 Faculty of Mechanical Engineering & Automation,Zhejiang Sci-Tech university,Hangzhou 310018,china Institute of Mathematical physics Zhejiang Sci-Tech University Hangzhou China Department of physics Shangqiu Normal University Shangqiu China Department of Mathematics Qingdao University Qingdao China Faculty of Mechanical Engineering & Automation Zhejiang Sci-Tech University Hangzhou China

Based on the property of the discrete model entirely inheriting the symmetry of the continuous system,we present a method to construct exact solutions with continuous groups of transformations in discrete nonconservative *** Noether's identity of the discrete nonconservative system is *** symmetric discrete Lagrangian and symmetric discrete nonconservative forces are defined for the *** quasi-extremal equations of discrete nonconservative systems are *** conserved quantities are derived with symmetries associated with the continuous *** have also found that the existence of the one-parameter symmetry group provides a reduction to a conserved quantity;but the existence of a two-parameter symmetry group makes it possible to obtain an exact solution for a discrete nonconservative *** examples are discussed to illustrate these results.

关键词： discrete nonconservative system symmetry conserved quantity quasi-extremal equation exact solution

Threshold proxy quantum signature scheme with threshold shared verification

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Science china(physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4 & WEN QiaoYan2 1 college of Computer Science and technology,Beijing university of technology,Beijing 100124,china 2 State Key Laboratory of Networking and Switching technology,Beijing university of Posts and Tele-communications,Beijing 100876,china 3 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 4 State Key Laboratory of Information Security(Graduate university of Chinese Academy of Sciences) ,Beijing 100049,china college of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (Graduate university of Chinese Academy of Sciences) Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Cis-regulatory element-based genome-wide identification of DREB1/CBF targets in Arabidopsis

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Progress in Natural Science:Materials International 2008年第5期18卷 579-583页

作者： Huan Zhao a, Weizhong Liu a,b, Yong Hu a, Xianglin Liu a, Yikun He a, a college of Life Science, Capital normal university, Beijing 100037, china b college of Life Sciences, Shanxi normal university, Linfen 041004, china college of Life Science Capital Normal University Beijing 100037 China college of Life Sciences Shanxi Normal University Linfen 041004 China

Microarray analysis is used to identify transcriptional targets. However, the direct targets of transcription factors cannot be distin- guished from indirect ones; further, genes with low-expression levels cannot be identi ed by this method. In the present study, we exploit the cis-element dehydration-responsive element (DRE) that is known to be responsible for the transcription of DRE binding factor 1 (DREB1) targets in the promoter region of all Arabidopsis genes. Putative targets whose promoters contain the elements were veri ed by both microarray and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Five new DREB1/CBF direct targets were identi ed. Compared with traditional microarray analysis, our method is convenient and cost-e ective for identifying the downstream targets of transcription factors.

关键词： Arabidopsis Cis-element Transcription factor DREB1/CBF Stress

Quantum threshold group signature

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4 1 college of Computer Science and technology, Beijing university of technology, Beijing 100124, china 2 State Key Laboratory of Integrated Services Network, Xidian university, Xi’an 710071, china 3 State Key Laboratory of Information Security (Graduate university of Chinese Academy of Sciences), Beijing 100049, china 4 State Key Laboratory of Networking and Switching technology, Beijing university of Posts and Tele-communications, Beijing 100876, china college of Computer Science and technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography