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An analytic relation for the thickness of accretion flows

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 82-85页

作者： CAI ZhenYi,GU WeiMin,XUE Li & LU JuFu department of physics and institute of theoretical physics and astrophysics,xiamen university,xiamen 361005,china 1. department of physics and institute of theoretical physics and astrophysics Xiamen University Xiamen 361005 China

We take the vertical distribution of the radial and azimuthal velocities into account in spherical coordinates,and find that the analytic relation cs0/υKΘ = [(γ-1)/2γ]1/2 is valid for both geometrically thin and thick accretion flows,where cs0 is the sound speed on the equatorial plane,υK is the Keplerian velocity,Θ is the half-opening angle of the flow,and γ is the adiabatic index.

关键词： accretion disks black hole physics hydrodynamics

表面压诱导的外消旋双亲分子单层手征相分离的数学模型及其二维古典解

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物理学报 1998年第10期47卷 1673-1679页

作者： YANG SHI XIN (department of Mathematics,xiamen university,xiamen\ 361005) (institute of theoretical physics Academia Sinica,Beijing\ 100080) 厦门大学数学系中国科学院理论物理研究所

研究表面压诱导的外消旋双亲分子单层手征相分离问题，通过视双亲分子单层为混合胆甾液晶薄膜、应用自由能极小化法所建立的数学模型，进而求出手性分离序参数与分子排列图案所满足的平衡方程的几类二维古典解．

关键词：手性分离双亲分子表面压数学模型外消旋

Lookback time as a test for f(R) gravity in the Palatini approach

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Research in Astronomy and astrophysics 2011年第11期11卷 1257-1265页

作者： Zhong-Xu Zhai and Wen-Biao Liu department of physics, institute of theoretical physics, Beijing Normal university, Beijing 100875, china department of physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

We use the recently released data of lookback time (LT)-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f (R) gravity in the Palatini formalism by considering the f (R) form of type (a) f (R) = R β/Rn and (b) f (R) = R + α ln R β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters (Ωm0, n) for (a) and (Ωm0, α) for (b). We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.

关键词： cosmology cosmic microwave background

Coexistence of normal, super-, and hyper-deformation in nuclei: A study with angular momentum projection method

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Chinese Science Bulletin 2009年第3期54卷 358-363页

作者： SUN Yang1,2, ZHANG JingYe3, LONG GuiLu4,5 & WU ChengLi6,7 1 department of physics, Shanghai Jiao Tong university, Shanghai 200240, china 2 Joint institute for Nuclear astrophysics, university of Notre Dame, Notre Dame, Indiana 46556, USA 3 department of physics and Astronomy, university of Tennessee, Knoxville, Tennessee 37996, USA 4 department of physics, Tsinghua university, Beijing 100084, china 5 Center of Nuclear Theory, Lanzhou National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 6 department of physics, xiamen university, xiamen 361005, china 7 department of physics, Chung Yuan Christian university, Chung-Li, Taiwan 32023, china department of physics Shanghai Jiao Tong University Shanghai 200240 China Joint institute for Nuclear astrophysics University of Notre Dame Notre Dame Indiana 46556 USA department of physics and Astronomy University of Tennessee Knoxville Tennessee 37996 USA department of physics Tsinghua University Beijing 100084 China Center of Nuclear Theory Lanzhou National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China department of physics Xiamen University Xiamen 361005 China department of physics Chung Yuan Christian University Chung-Li Taiwan 32023 China

Angular-momentum-projected energy surface calculations for A ≈ 110 nuclei indicate three distinct energy minima occurring at different angular-momenta. These correspond to normal, super-, and hy- per-deformed shapes coexisting in one nucleus. 110Pd is studied in detail, with a quantitative prediction on super- and hyper-deformed spectra by the Projected Shell Model calculation. It is found that several other neighboring nuclei in the A-110 mass region, with the neutron number around 64, also exhibit clear super- and hyper-deformation minima in the projected calculation.

关键词：原子核光谱角动量能量

Hawking radiation and thermodynamics of a Vaidya-Bonner black hole

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Research in Astronomy and astrophysics 2010年第1期10卷 33-38页

作者： Zhen-Feng Niu Wen-Biao Liu department of physics Hebei North University Zhangjiakou 075000 China department of physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

Using Parikh＇s tunneling method, the Hawking radiation on the apparent horizon of a Vaidya-Bonner black hole is calculated. When the back-reaction of particles is neglected, the thermal spectrum can be precisely obtained. Then, the black hole thermodynamics can be calculated successfully on the apparent horizon. When a relativistic perturbation is applied to the apparent horizon, a similar calculation can also lead to a purely thermal spectrum. The first law of thermodynamics can also be derived successfully at the new supersurface near the apparent horizon. When the event horizon is thought of as a deviation from the apparent horizon, the expressions of the characteristic position and temperature are consistent with the previous viewpoint which asserts that the thermodynamics should be based on the event horizon. It is concluded that the thermodynamics should be constructed exactly on the apparent horizon while the event horizon thermodynamics is just one of the perturbations near the apparent horizon.

关键词： black hole physics -- relativity -- kinematics and dynamics

The effect of tensor interaction on the halo structure of 31Ne

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The effect of tensor interaction on the halo structure of 31...

Mechano-chemical selections of two competitive unfolding pathways of a single DNA i-motif

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： Qiu Chen,Xian Rong Zhou~(1)) (department of physics and institute of theoretical physics and astrophysics,xiamen university,xiamen 361005,P.R.china)

The tensor interaction is important to reproduce the experimental isospin dependence of the spinorbit splittings in the N=82 isotones and Z=50 isotopes with the Skyrme Hartree-Fock（SHF） *** this paper,the effect of tensor interaction is discussed on halo structure of Ne within the deformed SHF+BCS *** SHF calculation with SLY5+T（with tensor interaction） can reproduce the experimental halo structure of Ne,while Ne is not a bound system according to the calculation without tensor force.

关键词： Tensor interaction halo structure 31Ne

来源： cnki会议评论

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cnki会议

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Chinese physics B 2014年第6期23卷 621-628页

作者：徐悦陈虎璩玉杰 Artem K.Efremov 黎明欧阳钟灿刘冬生严洁 State Key Laboratory of theoretical physics Institute of Theoretical Physics Mechanobiology institute National University of Singapore department of physics National University of Singapore School of physics University of Chinese Academy of Sciences department of physics Xiamen University Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University

The DNA i-motif is a quadruplex structure formed in tandem cytosine-rich sequences in slightly acidic conditions. Besides being considered as a building block of DNA nano-devices, it may also play potential roles in regulating chromo- some stability and gene transcriptions. The stability of i-motif is crucial for these functions. In this work, we investigated the mechanical stability of a single i-motif formed in the human telomeric sequence 51-（CCCTAA）3CCC, which revealed a novel pH and loading rate-dependent bimodal unfolding force distribution. Although the cause of the bimodal unfolding force species is not clear, we proposed a phenomenological model involving a direct unfolding favored at lower loading rate or higher pH value, which is subject to competition with another unfolding pathway through a mechanically stable inter- mediate state whose nature is yet to be determined. Overall, the unique mechano-chemical responses of i-motif-provide a new perspective to its stability, which may be useful to guide designing new i-motif-based DNA mechanical nano-devices.

关键词： single-molecule techniques i-motif folding/structure of biomolecules mechanical proper-ties/biomolecules

Studies of low-lying states of even-even Xe isotopes within the nucleon pair approximation

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 103-108页

作者： ZHANG LiHua1, JIANG Hui1,2 & ZHAO YuMin1,3,4 1institute of Nuclear, Particle, astrophysics and Cosmology, department of physics, Shanghai Jiao Tong university, Shanghai 200240, china 2School of Arts and Sciences, Shanghai Maritime university, Shanghai 200135, china 3Center of theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china 4CCAST, World Laboratory, P.O. Box 8730, Beijing 100080, china 1. institute of Nuclear Particle Astrophysics and Cosmology Department of Physics Shanghai Jiao Tong University Shanghai 200240 China2. School of Arts and Sciences Shanghai Maritime University Shanghai 200135 China3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 730000 China4. CCAST World Laboratory P.O. Box 8730 Beijing 100080 China

We study the relevance of nucleon pairs with higher spins, in addition to spin-zero and spin-two pairs (i.e., S D pairs), in low-lying states of even-even Xe nuclei. By including those higher-spin pairs in our configuration, we recalculate energy level schemes, elec trical quadrupole moments, magnetic moments and electric quadrupole transition rates, for low-lying states of even-even 128-142Xe nuclei. The agreement between our calculated results and the experimental data is substantially improved in comparison with previous studies.

关键词： nucleon pair approximation shell model configuration space low-lying states

1^(++)→Gq^- DECAY IN THE BROKEN QCD

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Chinese Science Bulletin 1985年第1期30卷 42-46页

作者：林仲金黄朝商赵光达 department of physics Xiamen University institute of theoretical physics Academia Sinica Beijing department of physics Peking University

Problems concerning massive gluons have been investigated in recent years. In Ref. [2] it is assumed that gluons acquire masses through spontaneous breaking of the local color gauge symmetry while quasiconfinement of gluons and quarks are still maintained. This may be called a broken QCD scheme. In order to distinguish the broken QCD from conventional QCD experimentally, the decay rate and branching ratio for the process 1++→2G which is not allowed in conventional QCD were studied in Ref. (2)Instead of using the calculated decay rate of 1++→Gqq in conven-

关键词： branching decay broken symmetry distinguish assumed Gq breaking spontaneous quark