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The information entropy of a static dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2008年第2期51卷 113-125页

作者： LIU ChengZhou Institute of theoretical physics, Binzhou University, Binzhou 256600, china Department of physics, Beijing Normal University, Beijing 100875, china Institute of theoretical physics Binzhou University Binzhou China Department of physics Beijing Normal University Beijing China

In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed.

关键词： black hole entropy holographic principle non-commutative quantum field theory event horizon loop quantum gravity

Dynamics of DNA in vitro evolution

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Progress in Natural Science:Materials International 2009年第2期19卷 137-144页

作者： Xiaojing Yang 1,Xili Liu 1,Chunbo Lou,Qi Ouyang center for theoretical Biology,School of physics,Peking University,Beijing 100871,china center for theoretical Biology School of Physics Peking University Beijing 100871 China

In vitro evolution has become a very important research area in recent years. From a practical point of view,it provides a powerful and reliable tool for engineering functional molecules (DNA,RNA or proteins) in reasonably short periods of time. From a theoretical point of view,since in vitro evolution is analogous to natural evolution in many respects,the study of the dynamic details of in vitro evolution may provide some instructive insights into the process of evolution. In this review,we summarize current theoretical and exper-imental studies,including several efforts made by our group,on the dynamics of DNA in vitro evolution.

关键词： DNA-TF interaction DNA in vitro evolution Natural evolution Crossover

Structure and optical properties of the Ge and Sn quantum-dots

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nuclear Science and Techniques 2000年第2期11卷 119-123页

作者： HAN Zhao-Hui ZHAO Zi-Qiang(Institute of heavy ion physics, Technical physics Depariment, Peking University,Beijing 100871) 北京大学北京 100871

Embedded cluster samples Ge:CaF2 and Sn:CaF2 with different sizes less than 8nm were produced and their optical properties were *** diffraction reveals that the clusters’ structures are crystallites and compared with the bulk Germanium and Stannum, lattice constants expand about 4.7% in the case of Ge:CaF2 and 5.2% of Sn:CaF2. Optical absorption and photoluminescence spectra of these samples show good agreement with the Quantum-Confinement-Effect(QCE) theory. With the decreasing of the cluster’s size, the energy gap broadens and the absorption edge blueshift is observed, and the absorption edge also shifts with the changing of the fraction of Sn and Ge. The XPS results show that in the cluster state,the binding energy becomes higher.

关键词：锗微晶锡微晶半导体 X射线光电子能谱结构光学性质电子衍射氟化钙

Normal scalar curvature and a pinching theorem in S^m×R and H^m×R

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Science china Mathematics 2011年第9期54卷 1977-1984页

作者： CHEN Qun 1,2 & CUI Qing 3,1,1 School of Mathematics and Statistics,Wuhan University,Wuhan 430079,china 2 International center for theoretical physics,Trieste 34100,Italy 3 School of Mathematics,Southwest Jiaotong University,Chengdu 610031,china School of Mathematics and Statistics Wuhan University Wuhan China International center for theoretical physics Trieste Italy School of Mathematics Southwest Jiaotong University Chengdu China

We obtain an inequality in Sm×R and Hm×R which is similar to DDVV *** an application,we show that a minimal submanifold in H m×R with nonnegative scalar curvature must be a surface of the type γ×R,where γ is a g... 详细信息

关键词： product spaces DDVV conjecture pinching theorem

Improved Glauber model for the reactions induced by Halo Nuclei and Stable Nuclei

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Improved Glauber model for the reactions induced by Halo Nuc...

Relativistic mean-field approximation with density-dependent screening meson masses in nuclear matter

CCAST“放射性束物理”研讨会

作者： Wenjun Guo, Huanqing Jiang, Jianye Liu Wei zuo, Zhongzhou Ren, Xiguo Lee, Zenghua Li1. center of theoretical nuclear physics, national laboratory of heavy ion accelerator,lanzhou 730000, P.R.china2. Institute of Modem physics, The Chinese Academy of Sciences, lanzhou 730000, P.R.china 3.Institute of High Energy physics, The Chinese Academy of Sciences, Beijing 100039, P.R.china4.physics department of Nanjing University, Nanjing 210008, P.R.china

＜正＞We develop the method for the calculation of the total reaction cross sections induced by thehalo nuclei and stable nuclei. This approach is based on the Glauber theory, which is valid for thereactions at high energies. It is extended for reactions at low energy and at the intermediate energy bycorrecting with the quantum correction and Coulomb correction under the assumption of the effectivenuclear density distribution. The calculated results for the total reaction cross section induced by stablenuclei agrees well with the experimental data within 10 percent accuracy. The comparison between thenumerical results and the experimental data for the neutron halo nucleiand the proton halo nucleiindicates a satisfactory agreement after considering the halo structure of these nuclei, which implies thequite different mean fields for the reactions induced by halo nuclei and stable nuclei. The halo nucleondistributions and the root mean square radii of these nuclei can be extracted from above ***, it is clear to see that the medium correction of the nucleon-nucleon collision has little effecton the total reaction cross sections induced by the halo nuclei due to the very weak binding and the veryextended density distribution, which is quite different from the reactions induced by the stable nucleiwith the salient medium correction.

关键词： total reaction cross section improved Glauber theory halo nuclei

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Relativistic mean-field approximation with density-dependent...

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

CCAST“兰州CSR上的介子物理”研讨会

作者： Bao-Xi Sun,Xiao-Fu Lu, Peng-Man Shen, Ea-Guang Zhao Institute of High Energy physics, The Chinese Academy of Sciences, P.O.Box 918(4), Beijing 100039, china Institute of theoretical physics, The Chinese Academy of Sciences, Beijing 100080, china Department of physics, Sichuan University, Chengdu 610064, china center of theoretical nuclear physics, national laboratory of heavy ion accelerator,lanzhou 730000, china Department of physics, Tsinghua University, Beijing 100084, china and china center of Advanced Science and Technology (World laboratory), Beijing 100080, china

＜正＞ The Debye screening masses of the σ,ωand neutral p mesons and the photon are calculated in the relativistic mean-field approximation. As the density of the nucleon increases, all the screening masses of mesons increase. It shows a different result with Brown-Rho scaling, which implies a reduction in the mass of all the mesons in the nuclear matter except the pion. Replacing the masses of the mesons with their corresponding screening masses in Walecka-1 model, five saturation properties of the nuclear matter are fixed reasonably, and then a density-dependent relativistic mean-field model is proposed without introducing the non-linear self-coupling terms of mesons.

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of physics and Bio-X disciplinary laboratory, Zhejiang University, Hangzhou 310027,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, china 2Institute of High Energy physics and Key laboratory of nuclear Analysis Techniques, Chinese Academy of Sciences, P.O. Box 918, Beijing 100039, china 3Wuhan Institute of physics and Mathematics, State Key laboratory of Magnetic Resonance and Atomic and Molecular physics, Chinese Academy of Sciences, Wuhan 430071, china Department of physics and Bio-X disciplinary laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan Institute of physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China Institute of High Energy physics and Key laboratory of nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2* signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser202 was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24 h after isoproterenol injection. (3) A sensitivity threshold of resting T2* signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

Anomalous Phenomena in E<18 keV Hydrogen ion Beam Implantation Experiments on Pd and Ti

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Chinese journal of nuclear physics 1997年第4期19卷 244-249页

作者： Wang Tieshan~(1) Piao Yubo~(2) Hao Jifang~(1) Wang Xuezhi~(2) Jin Genming~(1) Niu Zhanqi~(2) (1)Institute of Modern physics,the Chinese Academy of Sciences,lanzhou 730000 (2)Department of Modern physics of lanzhou University,lanzhou 730000 中科院近代物理所甘肃兰州兰州大学现代物理系甘肃兰州

Implantation experiments of low energy（1 keVmax1.2 mA/cm2)and lowbeam density(Jmin0.02 mA/cm2).Palladium and titanium foils（plates）are bombarded withproton and deuteron beams in order to compare the atomic and nucl... 详细信息

Implantation experiments of low energy（1 keVion beamson hydrogen loaded metals are performed with high beam density(Jmax1.2 mA/cm2)and lowbeam density(Jmin0.02 mA/cm2).Palladium and titanium foils（plates）are bombarded withproton and deuteron beams in order to compare the atomic and nuclear interactions between dif-ferent ion beams.X-ray and charged particles are measured,and neutron and gamma doses arealso monitored during the implantation *** anomalous peak in X-spectra,whoseenergy is about four times the beam energy,is observed during the high beam density *** peak moves from about 40 keV to 62 keV and FWHM reduces rapidly,while thebeam energy and intensity *** wide peak with over twice the beam energy is mea-sured in experiment with low beam *** is located between 16 keV and 30 keV,and itspeak energy increases with the increase of implantation dose（implantation time）.Some anoma-lous intensities of neutrons correlated with a charged particle peak（2.93,3.85 MeV）are alsoobserved in the deuteron-palladium *** highest neutron intensity reaches about8×104 n/s,while the beam energy and intensity are about 15 keV and 1.0 mA,respectively.

关键词： Hydrogen ion beam Low energy Implantation Palladium and titanium foils

Characterization of microarc oxidation coatings on pure titanium

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Rare Metals 2003年第1期22卷 42-48页

作者： XUE Wenbin, WANG Chao, Li Yongliang, and CHEN RuyiKey laboratory for Beam Technology and Materials Modification, Institute of Low Energy nuclear physics, Beijing Normal University, Beijing 100875, china 北京师范大学射线束技术与材料改性教育部重点实验室北京 100875

Key laboratory for Beam Technology and Materials Modification, Institute ofLow Energy nuclear physics, Beijing Normal UniversityThe morphology, composition, and phase structure of the oxide coatings produced on the surface ofpure titanium by alternating-current microarc discharge in aluminate solution were investigated byX-ray diffraction and scanning electron microscopy. The profiles of the hardness H and the elasticmodulus E in the coatings were determined using a nanoindentation method. The concentrationdistributions of Ti, Al, and O in the coating show that this coating over 30 mu m thick contains twolayers: an outer layer and an inner layer. The oxide coating is mainly composed of TiO_2 rutile andAl_2TiO_5 compounds. During oxidation, the temperature in the microarc discharge channel was veryhigh to make the local coating molten. From the surface to the interior of the coating, H and Eincrease gradually, and then reach maximum values of 9.78 GPa and 176 GPa respectively at a distanceof 7 mu m from the coating/titanium interface. They are also rather high near the interface.

关键词： pure titanium ceramic coating microarc oxidation microstructure nanoindentation