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Synthesis of superheavy nuclei with ^(238)U target

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3 & BAO JingDong2,4 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,beijing Normal university,beijing 100875,china 2 department of physics,beijing Normal university,beijing 100875,china 3 china Institute of Atomic Energy,beijing 102413,china 4 center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China department of physics Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 238U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112 and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 238U target

POPULATION DYNAMICS IN THE FOUR-PHOTON THREE-STEP PHOTOIONIZATION

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原子与分子物理学报 1994年第2期11卷 129-136+140页

作者： Shiliang Xie Dewu Wang Chuntion Ying(department of engineering physics, tsinghua university, beijing. PRC) 清华大学工程物理系北京

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ＰＯＰＵＬＡＴＩＯＮＤＹＮＡＭＩＣＳＩＮＴＨＥＦＯＵＲ－ＰＨＯＴＯＮＴＨＲＥＥ－ＳＴＥＰＰＨＯＴＯＩＯＮＩＺＡＴＩＯＮ￥ＳｈｉｌｉａｎｇＸｉｅ；ＤｅｗｕＷａｎｇ；ＣｈｕｎｔｉｏｎＹｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＥｎｇｉｎｅｅｒｉｎｇＰｈｙｓｉｃｓ，...

关键词： STEP POPULATION DYNAMICS IN THE FOUR-PHOTON THREE-STEP PHOTOIONIZATION

Current distribution and stability of LTS/HTS hybrid superconducting conductors

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Science china(Technological Sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2, WANG YinShun1 & ZHOU WeiWei3 1 Key Laboratory of HV and EMC beijing, North china Electric Power university, beijing 102206, china 2 department of physics, Baoding university, Baoding 071000, china 3 Institute of Electrical engineering, Chinese Academy of Sciences, beijing 100190, china 1. Key Laboratory of HV and EMC beijing North China Electric Power University Beijing 102206 China2. Department of Physics Baoding University Baoding 071000 China3. Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2223/Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2223/Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

Electronic structure and magnetism of R(Fe,Si)_(12) (R=Y,Nd)

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2, FAN Zhijian1, GAO Tao3 & QI Xinhua31. Institute of Nuclear physics and Chemistry, china Academy of engineering physics, Mianyang 621900, china 2. department of physics, Peking university, beijing 100871, china 3. Institute of Atomic and Molecular physics, Sichuan university, Chengdu 610065, china 1. Institute of Nuclear physics and Chemistry China Academy of Engineering Physics Mianyang 621900 China 2. department of physics Peking university Beijing 100871 China 3. Institute of Atomic and Molecular physics Sichuan University Chengdu 610065 China

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12 compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2 (R = Y, Nd) are larger than those of RFe10M2 (M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12(R = Y Nd) magnetic moment Density of state.

Spontaneous chiral-symmetry breaking of lattice QCD with massless dynamical quarks

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Science china(physics,Mechanics & Astronomy) 2007年第1期50卷 6-14页

作者： LUO XiangQian department of physics,School of physics and engineering,Sun Yat-Sen university,Guangzhou 510275,china 1. department of physics School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

One of the most challenging issues in QCD is the investigation of spontaneous chiral-symmetry breaking, which is characterized by the non-vanishing chiral condensate when the bare fermion mass is zero. In standard methods of the lattice gauge theory, one has to perform expensive simulations at multiple bare quark masses, and employ some modeled functions to extrapolate the data to the chiral limit. This paper applies the probability distribution function method to computing the chiral condensate in lattice QCD with massless dynamical quarks, without any ambiguous mass extrapolation. The results for staggered quarks indicate that this might be a promising and efficient method for investigating the spontaneous chiral-symmetry breaking in lattice QCD, which deserves further investigation.

关键词： lattice QCD spontaneous chiral-symmetry breaking dynamical quarks

Micro-plate magnetic chemiluminescence immunoassay and its applications in carcinoembryonic antigen analysis

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Science china Chemistry 2010年第4期53卷 812-819页

作者： LI ZhiYong1, ZHANG QianYun2, ZHAO LiXia1, LI ZhenJia3, HU GuoMao3, LIN Jin-Ming2 & WANG Shan4 1State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china 2department of Chemistry, tsinghua university, beijing 100084, china 3beijing Chemclin Biotech Co., Ltd., beijing Academy of Science and Technology, beijing 100094, china 4School of Chemistry and Chemical engineering, Xianyang Normal College, Xianyang 712000, china 1. State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Department of Chemistry Tsinghua University Beijing 100084 China3. Beijing Chemclin Biotech Co. Ltd. Beijing Academy of Science and Technology Beijing 100094 China4. School of Chemistry and Chemical Engineering of Xianyang Normal College Xianyang 712000 China

A micro-plate magnetic chemiluminescence immunoassay was developed for rapid and high throughput detection of carcinoembryonic antigens (CEA) in human sera. This method was based on a sandwich immunoreaction of fluorescein isothiocyanate (FITC)-labeled anti-CEA antibodies, CEA antigens, and horseradish peroxidase (HRP)-conjugated anti-CEA antibodies in mi- cro-plate. The immunomagnetic particles coated with anti-FITC antibodies were used as the solid phase for the immunoassay. The separation procedure was carried out by a magnetic plate adaptor and the luminol-hydrogen peroxide (H2O2)-HRP system was employed for the chemiluminescence detection. The proposed method combined the advantages of the micro-plate reactor and magnetic particle separation technology with the linear range of 5-250 ng mL·1. The detection limit of CEA was 0.61 ng mL·1. The coefficient of the variation was less than 7% and 13% for intra-assay and inter-assay precision, respectively. Compared with the commercial micro-plate chemiluminescent kit, the proposed method showed a good correlation.

关键词： micro-plate magnetic chemiluminescence immunoassay carcinoembryonic antigen tumor marker

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 1. department of physics Liaoning Normal University Dalian 116029 China2. Department of Physics and the State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China3. Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou 720000 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

Complete multiple round quantum dense coding with quantum logical network

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Chinese Science Bulletin 2007年第9期52卷 1162-1165页

作者： LI ChunYan1,2,LI XiHan1,2,DENG FuGuo1,2,3,ZHOU Ping1,2 & ZHOU HongYu1,2,3 1 Key Laboratory of Beam Technology and Material Modification of Ministry 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 Key Laboratory of Beam Technology and Material Modification of Ministry ofEducation Beijing Normal University Beijing 100875 China

We present a complete multiple round quantum dense coding scheme for improving the source ca-pacity of that introduced recently by Zhang et al. The receiver resorts to two qubits for storing the four local unitary ope... 详细信息

关键词：量子通信多重量子紧凑编码量子逻辑网络量子纠缠

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2,3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy physics, Chinese Academy of Sciences, beijing 100049, china 2. Graduate School of Chinese Academy of Sciences, beijing 100049, china 3. department of physics, Zhoukou Normal university, Zhoukou 466100, china 4. Research Imaging center, university of Texas Health Science center, San Antonio, Texas 78229, USA 5. National ASIC Design and engineering center, Institute of Automation, Chinese Academy of Sciences, beijing 100049, china 6. department of physics, Zhejiang university, Hangzhou 310027, china) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]department of physics Zhoukou Normal University Zhoukou China [d]Research Imaging center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and engineering center Institute of Automation Chinese Academy of Sciences Beijing China [f]department of physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.