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强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Zheng Xiangdong 1 ,Shen Chengde 2,Wan Guojiang 3,Tang Jie 4,Liu Kexin 5 1.Chinese Academy of Meteorological Sciences,beijing,100081,P.R.china 2.state key laboratory of Isotope Geochronology and Geochemistry,Guanzhou institute of Geochemistry,Chinese Academy of Sciences,Guanzhou 510640,P.R.china3.3.state key laboratory of Environment Geochemistry,institute of Geochemistry,Chinese Academy of Sciences,Guiyang,550002 P.R.china 4.Center of Meteorological sounding,Chinese Meteorological Administration,beijing,100081 5.state key laboratory of nuclear physics and technology & institute of heavy ion physics,peking university,beijing 100871,china

Mass concentration,13 C PDB(13 δC) of water-insoluble and refractory carbon(WIRC)as the proxy for black carbon(BC) chemically extracted from total suspended particles(TSP) samples collected from December 2002 to January 2004(50 samples) and from October 2005 to May 2006(29 samples) at Waliguan(36.287oN 100.898oE,3810 m) are *** concentration of WIRC was 1183 ± 120 ng/m 3,with the highest values in spring-winter,and its variation was in agreement with the optical BC concentration measured by aethalometer-but WIRC have higher values,especially in winter-spring with factor of *** seasonal mass concentration difference between WIRC and optical BC perhaps indicates that water soluble / insoluble carbon aerosols dominate the fraction of summer-autumn/winter-spring carbonaceous aerosols at the *** 13 δC of-25.3 ± 0.8‰ revealed that C3 plant burning was the major source of the WIRC.14 C PMC for the later 29 samples revealed that the overall mean fraction of contemporary-derived carbon(f C) of BC was 67.2 ± 7.7%(n = 29).The f C and BC concentration was strongly associated with air parcel *** f C accompanying moist air-parcels were transported from eastern Waliguan in autumn and early winter,but the continuous fossil combustion heating in the region decreased f C in late winter and ***-storm transport through the remote areas of western may have caused high f C even though mass concentrations of TSP and BC were abnormally ***-to-week variations of 210 Pb activity concentration in TSP and percentage of fossil-derived carbon(f f) were in agreement,providing some evidence that coal combustion was the dominant fossil source of BC at Waliguan.

关键词： water-insoluble and refractory carbon(WIRC) mass concentration 13δC 14C Mt.Waliguan

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Shape phase transitions in nuclei:Effective order parameters and trajectories

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 88-97页

作者： ZHANG Yu1,2, HOU ZhanFeng2 & LIU YuXin2,3 1Department of physics, Liaoning Normal university, Dalian 116029, china 2Department of physics and the state key laboratory of nuclear physics and technology, peking university, beijing 100871, china 3Center of Theoretical nuclear physics, National laboratory of heavy ion Accelerator, Lanzhou 720000, china Department of physics Liaoning Normal University Dalian China Department of physics and the state key laboratory of nuclear physics and technology Peking University Beijing China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

We analyze systematically the effective order parameters in nuclear shape phase transition both in experiments and in the interacting boson model. We find that energy ratios and B(E2) ratios can distinguish the first from the second-order phase transition in theory above a certain boson number N (about 50), but in experiments, only those quantities, such as E(L1+)/E(02+) and B(E2; (L+2)1 → L1)/B(E2; 21 → 01), etc., of which the monotonous transitional behavior in the second-order phase transition is broken in the first order phase transition independent of N, are qualified as the effective order parameters. By implementing the originally proposed effective order parameters and the new ones, we find that the isotones with neutron number Nn = 62 are a trajectory of the second order phase transition. In addition, we predict that the transitional behavior of isomer shifts of Xe, Ba isotopes and Nn = 62 isotones is approximately monotonous due to the finiteness of nuclear system.

关键词： nuclear shape phase transition interacting boson model effective order parameter finite particle number effect transition trajectory

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A new simulated annealing method of designing NMR biplanar shim coils

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Progress in Natural Science:Materials International 2006年第7期16卷 747-752页

作者： QI Feng, TANG Xin, WANG Weimin, SHEN Yifei, LIU Shaopo and JIANG Zhongde ( key laboratory for Quantum Information and Measurements of Ministry of Education, School of Electronics Engineering & Computer Science, peking university, beijing 100871, china institute of heavy ion physics, and beijing key laboratory of Medical physics and Engineering, Physical School, peking university, beijing 100871, china) peking Univ Sch Elect Engn & Comp Sci Minist Educ Key Lab Quantum Informat & Measurements Beijing 100871 Peoples R China peking Univ Sch Phys Beijing Key Lab Med Phys & Engn Beijing 100871 Peoples R China peking Univ Inst Heavy Ion Phys Beijing 100871 Peoples R China

A new SA (simulated annealing) method is presented for the design of longitudinal shim coils for NMR (nuclear magnetic resonance) equipment. First, AGL (adaptive Gauss-Lobatto) quadrature used by the traditional SA method is analyzed. Two kinds of complete elliptic integrals are introduced to integrate the spatial magnetic field, which increases the computing speed by 13. 3 times. Then, the system energy calculation is extended to the field of the z-axis. The results illustrate that the coil-set efficiency designed by the new SA method is 15 % higher than that of the traditional one, and the field inhomogeneity is reduced from 1.20 % to 0.49 % . Finally, a prototype of coil assembly for NMR rock-core analyzer is built, and the experimental results are in good agreement with the theoretically calculated results.

关键词： NMR shim coil design simulated-annealing method complete elliptic integral.

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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 730000, china 2Graduate university of Chinese Academy of Sciences, beijing 100049, china 3state key laboratory of nuclear physics and technology, School of physics, peking university, beijing 100871, china 4china institute of Atomic Energy, beijing 102413, china institute of Modern physics Chinese Academy of Sciences Lanzhou China Graduate university of Chinese Academy of Sciences Beijing China state key laboratory of nuclear physics and technology School of Physics Peking University Beijing China china institute of Atomic Energy Beijing 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

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Soil Properties in Two Soil Profiles from Terraces of the Nam Co Lake in Tibet,china

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Journal of Mountain Science 2009年第4期6卷 354-361页

作者： WANG Liqiang YI Chaolu Brigitta Sehiitt LIU Kexin ZHOU Liping institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Department of Physical Geography Freie University of Berlin Berlin12249 Germany state key laboratory of nuclear physics and technology Peking University Beijing 100871 China College of Urban and Environmental Sciences Peking University Beijing100871 China

This article investigates the soil properties in two soil profiles from the terraces of the Nam Co Lake in Tibet,china. Profile 1,with a slope aspect to east,is 37 m,and profile 2,to southwest,is 32 m above the lake level. Twelve and nine layers were identified in profile 1 and profile 2,respectively,based on the color,texture,structure,moisture content,presence of carbonate,and root density. Grain sizes and measurements of water content,total organic carbon,total inorganic carbon,total carbon,pH value and electrical conductivity were all analyzed for each sample. The results show that soil is poorly developed because of sparse vegetation coverage and weak chemical weathering in the cold and arid area. The results also indicate that the soil properties are different between the two profiles and suggest that soil is better developed in profile 1 than in profile 2. These differences are ascribed to the dissimilarity of landform,vegetation and timing. Profile 1 faces to east as compared with profile 2 facing to southwest and gets less insolation and therefore less evaporation. Thus,vegetation grows better in profile 1 than in profile 2. Radiocarbon dating and OSL dating show that profile 1 underwent a longer soil forming process than profile 2,which is helpful for the soil development in profile 1.

关键词： Soil property Soil genesis Environmental change Marine isotope stage 3 (MIS 3)

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Differential Cross Section Measurement for the ~6Li(n,t)~4He Reaction

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中国核科技报告 2002年第S1期 5-7页

作者： ZHANG Guohui TANG Guoyou CHEN Jinxiang SHI Zhaomin institute of heavy ion physics & MOE key laboratory of heavy ion physics, peking university, beijing 100871CHEN Zemin Department of physics, Tsinghua university, beijing 100084Yu.M.Gledenov M. Sedysheva G. Khuukhenkhuu Joint institute for nuclear Research, Frank laboratory of Neutron physics, Dubna 141980, Russia

The differential cross sections and integrated cross sections of the 6Li(n,t)4He reaction were measured at 1.85 and 2.67 MeV by using a gridded ionization chamber. Neutrons were produced through the T(p,n)3He reaction. The absolute neutron flux was determined through the 238U(n,f) reaction. Present results are compared with existing data.

关键词： Li Differential Cross Section Measurement for the n,t

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The Isovector Channel of the Energy Density Functional

The Isovector Channel of the Energy Density Functional

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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： Xiaobao Wang~1 Chong Qi~2 Furong Xu~(1,3) 1 School of physics,and state key laboratory of nuclear physics and technology,peking university,beijing 100871,china 2 KTH,Alba Nova university Center,SE-10691 Stockholm,Sweden. 3 Center for Theoretical nuclear physics,National laboratory for heavy ion physics,Lanzhou 730000,china

Both relativistic and non-relativistic energy density functional models have been widely used in describing the nuclear many-body *** calculations show that both relativistic and non-relativistic models give quite similar results for the ground state properties and low-energy dynamics of stable ***,significant differences are found when calculations go to the extreme cases of high isospin and high *** origin of these differences is still not *** non-relativistic Skyrme-Hartree-Fock (SHF) model has been extensively employed in the investigation of nuclear structure since the first work of Vautherin and *** 1970s,almost at the same time as SHF,the Relativistic-Mean-Field(RMF) model was developed to give a competitive description of finite *** relativistic Quark-Meson-Coupling model(QMC) was proposed by ***,the Hartree approximation is usually used in both RMF and QMC *** real treatment of the Fock term remains *** comparisons between relativistic models within the non-relativistic Hartree-Fock approximation and the Skyrme model can be instructive in clearing the *** this work,we compare the non-relativistic approximations of the QMC and RMF models and SHF models,with focusing on possible *** list the QMC energy density functional within the Hartree-Fock approximation and make comparison with RMF and Skyrme *** find that the discrepancy of these models is mainly caused by the isovector channel of the energy density functional.A new Skyrme parametrization is obtained by the *** also give the calculation results of the new parametrization.

关键词： energy density functional non-relativistic approximation Skyrme parametrization

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Study of proton resonances in ^(18)Ne via resonant elastic scattering of ^(17)F+p and its astrophysical implication

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 32-36页

作者： HE JianJun1, HU Jun1,2, XU ShiWei1, CHEN ZhiQiang1, ZHANG XueYing1, WANG JianSong1, YU XiangQing1, ZHANG LiYong1,2, LI Long1,2, YANG YanYun1,2, MA Peng1,2, ZHANG XueHeng1, HU ZhengGuo1, GUO ZhongYan1, XU Xing1,2, YUAN XiaoHua1, LU Wan1,2, YU YuHong1, ZANG YongDong1,2, TANG ShuWen1,2, YE RuiPing1,2, CHEN JinDa1,2, JIN ShiLun1,2, DU ChengMing1,2, WANG ShiTao1,2, MA JunBing1,2, LIU LongXiang1,2, BAI Zhen1,2, LEI XiangGuo1, SUN ZhiYu1, ZHANG YuHu1, ZHOU XiaoHong1, XU HuShan1, SU Jun3, LI ErTao3, WANG HongWei4, TIAN WenDong4 & LI XiangQing5 1 institute of Modern physics (IMP), Chinese Academy of Sciences, Lanzhou 730000, china 2 Graduate university of Chinese Academy of Sciences, beijing 100049, china 3 china institute of Atomic Energy (CIAE), beijing 102413, china 4 Shanghai institute of Applied physics (SINAP), Chinese Academy of Sciences, Shanghai 201800, china 5 School of physics and state key laboratory of nuclear physics and technology, peking university, beijing 100871, china institute of Modern physics (IMP) Chinese Academy of Sciences Lanzhou China Graduate university of Chinese Academy of Sciences Beijing China china institute of Atomic Energy (CIAE) Beijing China Shanghai institute of Applied physics (SINAP) Chinese Academy of Sciences Shanghai China School of physics and state key laboratory of nuclear physics and technology Peking University Beijing China

The proton resonant properties in 18Ne, which determine the reaction rate of the key stellar 14O(α,p)17F reaction, have been studied by using a technique of proton resonant elastic scattering of 17F+p. A 4.22 MeV/nucleon 17F radioactive ion (RI) beam was produced via a projectile-fragmentation reaction, and separated by a Radioactive ion Beam Line in Lanzhou (RIBLL). By bombarding a thick (CH2)n target, the energy spectra of the recoiled protons were measured by two ΔE-E silicon telescopes at the center-of-mass scattering angles of θc.m.≈175°±5°, θc.m.≈152°±8°, respectively. Several proton resonances in 18Ne were ob served clearly. A further R-matrix analysis of the experimental data is under way to determine the resonant parameters. The present work reports the preliminary results briefly.

关键词： resonant reaction reaction rate explosive burning accreting binary systems

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Transmission degradation of the laser pulse due to the pre-plasma filling of the opened cone targets

Transmission degradation of the laser pulse due to the pre-p...

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第十五届全国等离子体科学技术会议

作者： Feng Liu~1,Bicheng Liu~(1,2,3),Xiaoxuan Lin~1,Fei Du~1,Wenjun Ding~1,Xiaolong Liu~1,Jinglong Ma~1, Yutong Li~1 1 institute of physics,Chinese Academy of Sciences,beijing 100190 2 Graduate university of Chinese Academy of Sciences,beijing 100190 3 state key laboratory of nuclear physics and technology,institute of heavy ion physics,peking university,beijing 100871

Irradiated by laser pulses with different energies,the opened cone target behaves very differently on the transmission of the incident laser *** the incident laser energy is low enough,the cone target is like an optical device to reflect the pulse laser and part of the laser energy can transmit the *** contrast,when the incident laser energy is high enough to generate plasmas,which fill the inner cone,the cone will

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A bound on the effective boson number from shape phase transition in IBM

A bound on the effective boson number from shape phase trans...

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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： Yu Zhang~(1 2)) Zhan-feng Hou~(2)) Yu-xin Liu~(2 3)) Feng Pan~(1)) 1(Department of physics,Liaoning Normal university,Dalian 116029,china) 2(Department of physics and state key laboratory of nuclear physics and technology peking university,beijing 100871, china) 3(Center of Theoretical nuclear physics,National laboratory of heavy ion Accelerator,Lanzhou 730000,china)

We study the effects driven by the boson number on the critical behavior of some observable quantities that are sensitive to the nuclear shape phase transitions in the interacting boson model（IBM）.By comparing the experiments with the theory calculation,we find that the effective boson number in IBM best consistent to experiments is not more than the total pairs number of valence nucleons or holes,and an up bound of the effective boson number can be found in the U（5）-O（6） transition region at least in ***, two trajectories of second order phase transitions,the isotones with neutron number N_n=62 and the one with N_n=74,are confirmed by comparing the observable quantities in experiments with those in theory

关键词： keyword1 keyword2 keyword3 keyword4

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