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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 energy,beijing 102.13,china. china institute of atomic energy

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 energy,beijing 102.13,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

STUDY OF PHASES IN U-10wt%Zr ALLOY BY NEUTRON DIFFRACTION

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Acta Metallurgica Sinica(English Letters) 1995年第3期8卷 174-180页

作者： XIE Guoqiang YANG Jijian ZHANG Baisheng LI Wendan(china institute of atomic energy, beijing) china Inst of atomic energy Beijing China

U 10wt%Zr alloy has been analysed by neutron diffraction method to determine the constituent phases and their crystal *** collected diffraction data are processed using Rietveld' s profile technique (with program“ Fullprof ”). Four phases,α-U,δ, γand α Zr, in the alloy at room temperature and the corresponding volume fractions as well their structural parameters are obtained from the data analysis, For the δ-phase, a partially ordered unusual hexagonal structure of the modified C32(AlB2) type is confirmed.

关键词： U-10wt%Zr alloy neutron diffraction δ-phase

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 energy,P.O.Box 275,beijing 102.13) 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

Study for ^(228)Th reduction in thermal reactor with Th-U fuel cycls

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Nuclear Science and Techniques 1999年第1期10卷 48-50页

作者： XU Xiaoqin (china institute of atomic energy, beijing 10241s) china institute of atomic energy Beijing 102413 China

By using computer code WIMS/CENDL, the effects of some parameters, core configuration such as fuel element structure, neutron flux and burn-up, are discussed in this paper. It is shown that high neutron flux, small fuel rod diameter, large volume ratio of coolant to fuel, seed-blank heterogeneous core arrangement and 231 Pa chemical separation are necessary for reducing 228Th production in reactor.

关键词：热反应堆钍-铀 228钍减少

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 energy, P. O. Box 275-51, beijing 102.13, china china institute of atomic energy 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 1.35X10^4 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 Y12. matrix materials.

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

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 102.13, 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 energy 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(30Si,4n)270Hs, 238U(36S,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 238U(36S,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. institute 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 institute of atomic energy, beijing 102.13, 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 energy 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

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 energy, beijing 102.13) china institute of atomic energy 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