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FirstIdentificationofLevelSchemesinNeutron─richIsotopes141Xe,152Ceand160Sm
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作者 朱胜江 王牧歌 +12 位作者 邓景康 HamiltonJH RamayyaAV BabuBRS MaWC RasmussenJ StoyerMA ChuSY LeeIY ColeJD AyaeinejadR JohnsonNR McGowanFK 《Tsinghua Science and Technology》 EI CAS 1996年第3期9-13,共5页
Level schemes of the extremely neutron rich isotopes, 141 Xe, 152 Ce and 160 Sm are identified for the first time using γ γ, γ γ γ, X γ( and X X coincidence ex... Level schemes of the extremely neutron rich isotopes, 141 Xe, 152 Ce and 160 Sm are identified for the first time using γ γ, γ γ γ, X γ( and X X coincidence experiments through measuring prompt γ rays from spontaneous fission of 252 Cf. Two collective band structures are observed in 141 Xe that most probably belong to octupole deformation. The yrast bands up to 16 + in 152 Ce and 14 + in 160 Sm demonstrated well deformed character. Two side bands in 152 Ce are tentatively assigned as octupole vibrational rotational bands with K=1 - and 2 - respectively. The behavior of J 1 with h- ω in Ce and Sm isotope chains is also discussed. 展开更多
关键词 nuclear structure level schemes high spin states 141 Xe 152 Ce and 60 Sm
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Novel Discrete Particle Swarm Optimization Based on Huge Value Penalty for Solving Engineering Problem 被引量:7
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作者 YU Ying YU Xiaochun LI Yongsheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第3期410-418,共9页
For the purpose of solving the engineering constrained discrete optimization problem, a novel discrete particle swarm optimization(DPSO) is proposed. The proposed novel DPSO is based on the idea of normal particle s... For the purpose of solving the engineering constrained discrete optimization problem, a novel discrete particle swarm optimization(DPSO) is proposed. The proposed novel DPSO is based on the idea of normal particle swarm optimization(PSO), but deals with the variables as discrete type, the discrete optimum solution is found through updating the location of discrete variable. To avoid long calculation time and improve the efficiency of algorithm, scheme of constraint level and huge value penalty are proposed to deal with the constraints, the stratagem of reproducing the new particles and best keeping model of particle are employed to increase the diversity of particles. The validity of the proposed DPSO is examined by benchmark numerical examples, the results show that the novel DPSO has great advantages over current algorithm. The optimum designs of the 100-1 500 mm bellows under 0.25 MPa are fulfilled by DPSO. Comparing the optimization results with the bellows in-service, optimization results by discrete penalty particle swarm optimization(DPPSO) and theory solution, the comparison result shows that the global discrete optima of bellows are obtained by proposed DPSO, and confirms that the proposed novel DPSO and schemes can be used to solve the engineering constrained discrete problem successfully. 展开更多
关键词 discrete particle swarm optimization location updating scheme of constraints level huge value penalty optimization design BELLOWS
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Quest for Chirality in ^(107)Ag 被引量:1
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作者 贺创业 张彪 +10 位作者 竺礼华 吴晓光 孙慧斌 郑云 于蓓蓓 王烈林 李广生 姚顺和 徐川 王建国 顾龙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第6期518-520,共3页
High spin states in 107Ag have been studied via the 100Mo (11B, 4n) 107Ag reaction at a beam energy of 60 MeV on the HI-13 tandem accelerator at the China Institute of Atomic Energy. By analyzing the gamma-gamma coi... High spin states in 107Ag have been studied via the 100Mo (11B, 4n) 107Ag reaction at a beam energy of 60 MeV on the HI-13 tandem accelerator at the China Institute of Atomic Energy. By analyzing the gamma-gamma coincidence and their DCO ratios, a new level scheme of 107Ag is presented. The structures for the newly constructed bands are briefly discussed and tentatively assigned to be chiral doublet bands. 展开更多
关键词 high spin states level scheme CHIRALITY
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High Spin Structure in ^(106)Pd
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作者 于蓓蓓 竺礼华 +11 位作者 贺创业 吴晓光 郑云 李广生 王烈林 姚顺和 张彪 徐川 郝昕 王建国 顾龙 张明 《Plasma Science and Technology》 SCIE EI CAS CSCD 2012年第6期531-533,共3页
The high spin states of 106pd have been populated through the 100Mo(11B, lp4n)106Pd reaction using a beam energy of 60 MeV provided by the Beijing HI-13 tandem accel- erator at China Institute of Atomic Energy. By a... The high spin states of 106pd have been populated through the 100Mo(11B, lp4n)106Pd reaction using a beam energy of 60 MeV provided by the Beijing HI-13 tandem accel- erator at China Institute of Atomic Energy. By analyzing the V-3' coincidence relation and DCO raios of transitions, 3 rotational bands with 13 new states and 22 new 7 transitions belonging to 106pd were constructed. Bands 2 and 3 with negative parity were supposed to build on the vh1l/297/2 and vh11/2ds/2 configuration, respectively. 展开更多
关键词 heavy ion fusion-evaporation reaction high spin state level scheme rotational band structure
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Level structure of the double-shell closure system with Z=14 and N=20:^(34)Si
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作者 Chang-Bum Moon 袁岑溪 《Chinese Physics C》 SCIE CAS CSCD 2022年第12期226-231,共6页
The level structure of the double-magic nucleus ^(34)Si(Z=14,N=20)was investigated by evaluating the available data.On the basis of experimental results from the beta-decay and fusion-evaporation reactions,we establis... The level structure of the double-magic nucleus ^(34)Si(Z=14,N=20)was investigated by evaluating the available data.On the basis of experimental results from the beta-decay and fusion-evaporation reactions,we established the level scheme by assigning spin-parities up to 6_(1)^(+)at 6233 keV.The high energy positions of the excited states are consistent with the magicity at ^(34)Si,such as the 2_(2)^(+)state of the spherical ground band at 4.519 MeV and the 3^(-),4^(-),and 5^(-)states of the one-particle one-hole cross-shell states at approximately 4.5 MeV.This nucleus,for a long time,has attracted much attention because of,on one side,a proton bubble structure in the ground state and,on the other side,a deformation in the second 0^(+)state,0_(2)^(+).By a comparison of the constructed level scheme with the shell model calculations,we describe the emerging structures in the ground and second 0+states and the negative-parity 3^(-)states within the framework of the shell model context.We propose a deformed rotational band with the cascading 6_(2)^(+)−4_(1)^(+)−2_(1)^(+)transitions built on the 0_(2)^(+)state. 展开更多
关键词 double shell closure level scheme two particle-two hole excitations large-scale shell model calculations
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Level structure of ^(159)Lu
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作者 盛海清 翟健 +10 位作者 李险峰 马英君 赵延新 王亚坤 赵磊 竺礼华 吴晓光 贺创业 刘颖 郝昕 李雪琴 《Chinese Physics C》 SCIE CAS CSCD 2009年第S1期164-166,共3页
The high-spin states of 159Lu were populated by fusion-evaporation reaction 144Sm (19F, 4n) with beam energy 106 MeV. A new level scheme was established, which consists of the yrast band with negative parity, the octu... The high-spin states of 159Lu were populated by fusion-evaporation reaction 144Sm (19F, 4n) with beam energy 106 MeV. A new level scheme was established, which consists of the yrast band with negative parity, the octupole vibration band based on the states and quasipartical band with positive parity. The high spin states of 159Lu were discussed by systemic characteristics. 展开更多
关键词 high spin states level scheme octupole deformation
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High spin states in stable nucleus ^(84)Sr 被引量:4
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作者 KANG XuZhong SHEN ShuiFa +6 位作者 HAN GuangBing PAN Feng GU JianZhong DRAAYER J P WU XiaoGuang ZHU LiHua WEN TingDun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第10期1861-1867,共7页
High spin states of 84Sr were populated through the reaction 70Zn(18O,4n)84Sr at 75 MeV beam energy.Measurement of excitation function,γ-γ coincidences,directional correlation from oriented state (DCO) ratios and γ... High spin states of 84Sr were populated through the reaction 70Zn(18O,4n)84Sr at 75 MeV beam energy.Measurement of excitation function,γ-γ coincidences,directional correlation from oriented state (DCO) ratios and γ-transition intensities were performed using eight anticompton HPGe detectors and one planar HPGe detector.Based on the measured results,a new level scheme of 84Sr was established in which 12 new states and nearly 30 new γ-transitions were identified in the present work.The positive-parity states of the new level scheme were compared with the results from calculations in the framework of the projected shell model (PSM).One negative-parity band was extended to spin Iπ=19-and it can be found that in the high spin states,the γ-transition energies show the nature of signature staggering.The negative-parity band levels are in good agreement with deformed configuration-mixing shell model (DCM) calculations. 展开更多
关键词 high spin states γ-γcoincidence DCO ratio level scheme PSM
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New band structures in ^(107)Ag 被引量:1
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作者 张彪 竺礼华 +13 位作者 孙慧斌 贺创业 吴晓光 陆景彬 马英君 郝昕 郑云 于蓓蓓 李广生 姚顺和 王烈林 徐川 王建国 顾龙 《Chinese Physics C》 SCIE CAS CSCD 2011年第11期1009-1012,共4页
High spin states in 107Ag are studied via the 100Mo(11B,4n) 107Ag reaction at an incident beam energy of 60 MeV. Prompt γ-γ coincidence and DCO ratios are measured by the detector arrays in CIAE. The level scheme ... High spin states in 107Ag are studied via the 100Mo(11B,4n) 107Ag reaction at an incident beam energy of 60 MeV. Prompt γ-γ coincidence and DCO ratios are measured by the detector arrays in CIAE. The level scheme has been updated and a new negative band belonging to 107 Ag is identified. The new negative side band has been constructed and its configuration is tentatively assigned to πg9/2νh11/2(g7/2/d5/2). 展开更多
关键词 high spin states level scheme routhian ALIGNMENT
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EXPERIMENT ON THE FORECAST OF CHARACTERISTIC QUANTITIES OF ATMOSPHERIC TURBULENCE BY MESOSCALE MODEL MM5 被引量:2
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作者 赵鸣 许丽人 汤剑平 《Acta meteorologica Sinica》 SCIE 2002年第1期94-106,共13页
In nested nonhydrostatic mesoscale model MM5,the characteristic quantities of atmospheric turbulence,i.e.,the standard deviations of the turbulent fluctuated speeds for three directions in PBL are computed by Mellor-Y... In nested nonhydrostatic mesoscale model MM5,the characteristic quantities of atmospheric turbulence,i.e.,the standard deviations of the turbulent fluctuated speeds for three directions in PBL are computed by Mellor-Yamada's level 2.5 closure scheme.The magnitudes and the vertical profiles of these quantities computed from the model are closely connected with temperature and wind speed profiles as well as the type of the ground with a significant diurnal variation,and are in agreement with known magnitudes and regularities in different stratification conditions.Hence the method in this paper is reasonable and convincible.Their horizontal distribution depends on the horizontal distribution of the stratification.The method of predicted characteristic quantities of turbulence from mesoscale model in this paper can be used in the problem of atmospheric diffusion and atmospheric environment. 展开更多
关键词 atmospheric turbulence standard deviation of turbulent speed mesoscale model MM5 level 2.5 closure scheme
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Shears bands in ^(112)In
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作者 李雪琴 竺礼华 +13 位作者 吴晓光 贺创业 刘颖 潘波 郝昕 李立华 王治民 李广生 李忠宇 王守宇 徐强 王建国 丁怀博 翟建 《Chinese Physics C》 SCIE CAS CSCD 2009年第S1期209-211,共3页
A new level scheme of 112In have been established up to 6.8 MeV in excitation energy and to a tentative spin of (21+) through the reaction 110Pd(7Li,5n)112In at a beam energy of 50 MeV. In-beam measurements involving ... A new level scheme of 112In have been established up to 6.8 MeV in excitation energy and to a tentative spin of (21+) through the reaction 110Pd(7Li,5n)112In at a beam energy of 50 MeV. In-beam measurements involving γ-γ coincidences and directional correlation of oriented states were performed. M1 bands consisting of I =1 dipole transitions have been observed. Possible quasiparticle configurations suggest that these bands are similar to the shears bands observed in Pb nuclei. 展开更多
关键词 high spin state in-beam gamma-ray spectroscopy level scheme shear rotational band
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High-spin states in ^(128)I
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作者 郑云 竺礼华 +10 位作者 吴晓光 李广生 郝昕 王烈林 贺创业 刘颖 李雪琴 潘波 汪雷 李忠宇 丁怀博 《Chinese Physics C》 SCIE CAS CSCD 2009年第S1期179-181,共3页
The high-spin states in 128I have been studied by using in-beam γ-ray spectroscopy with the 124Sn(7Li,3n)128I reaction at beam energies of 25, 28 and 42 MeV. A new level scheme including 20 new levels and 27 new γ-t... The high-spin states in 128I have been studied by using in-beam γ-ray spectroscopy with the 124Sn(7Li,3n)128I reaction at beam energies of 25, 28 and 42 MeV. A new level scheme including 20 new levels and 27 new γ-transitions for 128I has been established preliminarily. 展开更多
关键词 high spin state level scheme doubly odd nucleus
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