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FROM UNWEIGHTED TO WEIGHTED GENERALIZED FAREY ORGANIZED TREE AND THE PYRAMID NETWORKS

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Journal of Systems Science & Complexity 2010年第4期23卷 681-700页

作者： Yong LI·Jinqing FANG·Qiang LIU china institute of atomic {3.,beijing 102413.china. china institute of atomic {3.

Generalized Farey tree network （GFTN） and generalized Farey organized pyramid network （CFOPN） model are proposed, and their topological characteristics are studied by both theoretical analysis and numerical simulations, which are in good accordance with each other. Then weighted GFTN is studied using cumulative distributions of its Farey number value, edge weight, and node strength. These results maybe helpful for future theoretical development of hybrid models.

关键词： Generalized Farey organized pyramid network topological properties weighted generalized Farey tree network.

Theoretical research progress in complexity of complex dynamical networks

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Progress in Natural Science:Materials International 2007年第7期17卷 761-774页

作者： Fang Jinqing(Joint Complex Network Research Group,china institute of atomic {3.,beijing 102413.china) [a]Joint Complex Network Research Group China Institute of Atomic Energy Beijing China

This article reviews the main progress in dynamical complexity of theoretical models for nonlinear complex networks proposed by our Joint Complex Network Research Group(JCNRG).The topological and dynamical properties of these theoretical models are numerically and analytically *** findings are useful for understanding and deeply studying complex networks from macro- scopic to microscopic levels and have a potential of applications in real-world networks.

关键词： Harmonions unifying hybrid preferential model a large unifying hybrid network model quantum interference network nonowire networks generalized local-world model non-local links model evolving model of weighted networks small-world network with the unchanged degree

Effects of Y211 phase contents on the critical current density J_c and microstructural analysis in YBCO bulk superconductors

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Rare Metals 2002年第4期21卷 282-288页

作者： SHA Jianjun, YU Gang, and YU Jinnanchina institute of atomic {3., P. O. Box 275-51, beijing 102413. china china institute of atomic {3. P.O. Box 275-51 北京 102413

YBCO bulk superconductors were prepared by the solid state reaction andtop-seed-melt-textured growth (TSMTG) process. By using the AC susceptibility measurement, thecritical transition temperature T_c of samples is 91.5 K for the highest value, and the transitionwidth ΔT_c is less than 1 K. The highest magnetization critical current densities J_c achieved 10~6A/cm^2 under 5 T at 10 K and 1.3.X10^4 A/cm^2 under 2 T at 70 K (H//c), respectively. The resultscombining the SEM observation indicate that doping of Y211 particles is more effective in improvingthe growth quality of melt-textured YBCO superconductor and in reducing the micro-cracks ofspecimens. Doping of Y_2O_3.powder forms the rod-shaped Y211 particles, but doping of Y211 particlesdirectly to matrix materials forms the spherical Y211 particles mainly. Combining themicrostructures with J_c measurements shows that the interfaces are most important on flux bundlepinning, in which the gradient of free energy is larger than that of other place between the Y211particles and the Y123.matrix materials.

关键词： quasi-single domain melt-textured Y211 particles critical current density magnetic flux pinning

The Angular Distribution of Light Composite Particle Projectile in Preequilibrium Reactions

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Chinese journal of nuclear physics 1994年第2期16卷 160-169页

作者： Shen Qingbiao(china institute of atomic {3.,P.O.Box 275,beijing 102413. china Inst of atomic energy Beijing China

Formulations of double differential cross sections of light composite particleconsidering (1,m) and (2,m) pickup type reactions simultaneously for semi-classicalmulti-step compound and direct processes are *** calculated results of crosssections,spectra,and double differential cross sections indicate that generally the con-tributions of the (2,m) pickup type reactions are about 15%-25% when the incident en-ergies are below 50 MeV but can become dominant when the incident energies areabove 50 MeV in some region of the outgoing energies and *** forward tenden-cy of the calculated angular distributions by (2,m) configuration is weaker than those by(1,m) *** the reactions of outgoing composite particle with higher inci-dent energy,the multi-step direct process must be considered.

关键词： Preequilibrium Composite particle Double differential cross section

Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, beijing Normal University, beijing 100875, china 2. Physics Department, beijing Normal University, beijing 100875, china 3. china institute of atomic energy, beijing 102413. china Key Laboratory of Beam Technology Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics Department Beijing Normal University Beijing 100875 China china institute of atomic {3. Beijing 102413 China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 248Cm(26Mg,4n)270Hs, 244Pu(3.Si,4n)270Hs, 23.U(3.S,4n)270Hs and 226Ra(48Ca,4n)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(48Ca,4n)270Hs and 23.U(3.S,4n)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Exotic structure of the third excited state in^(21)Na

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Chinese Science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2,3. LIANG Yujie1,2,3. DENG Fuguo1,2,3. LIU Zuhua1,4 & ZHOU Hongyu1,2,3.1. Key Laboratory of Beam Technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875, china 2. {3. of Low energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal University, beijing 100875, china 3. beijing Radiation Center, beijing 100875, china 4. china {3. of {13. energy, beijing 102413. china Key Laboratory of Beam Technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China institute of Low energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China china institute of atomic {3. Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2= of the third excited state in 21Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 1/2=5.28 fm respectively. The P value and the contribution of the asymptotic part to the 1/2 are compared with those of several other low energy states in 21Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 20Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 21Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

β-delayed proton decays near the proton drip line

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2. Nuclear Physics Department, china institute of atomic energy, beijing 102413. china 3. Department of Technical Physics, Peking University, beijing 100871, china 4. Shanghai institute for Nuclear Research, Shanghai 201800, china 1. institute of Modern Physics Chinese Academy of Sciences 730000 Lanzhou China 2. Nuclear Physics Department China Institute of Atomic Energy 102413 Beijing China 3. Department of Technical Physics Peking University 100871 Beijing China 4. Shanghai institute for Nuclear Research 201800 Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.

Influence of some factors on alpha energy spectrum of^(241)Am fire alarm source

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Nuclear Science and Techniques 1999年第1期10卷 11-13页

作者： FENG Gensheng FENG Xinzhan LI Shujuan (china institute of atomic {3., beijing 102413. china institute of atomic {3. Beijing 102413 China

Several primary factors influencing the alpha energy spectrum of 241Am fire alarm source have been studied in order to get better alpha energy spectrum. The results show that the homogeneity and the thickness of metal surface coat and the size of active area of the source have considerable influence on the alpha energy spectrum of the source.

关键词：火警 241Am警报源 α-能谱

Properties of the 3.2^-[521] band in the odd-N rare-earth nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 37-43页

作者： CHEN Liang1,2, ZHOU XiaoHong1,2, ZHANG YuHu1, ZHANG ShuangQuan3.& ZHU LiHua4 1institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2Graduate University of Chinese Academy of Sciences, beijing 100049, china 3.tate Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, beijing 100871, china 4china institute of atomic energy, beijing 102413. china 1. institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. State Key Laboratory of Nuclear Physics and Technology School of Physics Peking University Beijing 100871 China4. China Institute of Atomic Energy Beijing 102413 China

High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3.2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3.2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3.2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated with the 3.2-[521] configuration in the rare-earth region is discussed. The band properties are analyzed within the framework of a triaxial particle-rotor model, and a triaxial deformation is proposed to the 3.2-[521] band.

关键词： high-spin states signature inversion triaxial particle-rotor model