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Shell effect and capture cross sections in the synthesis of superheavy nuclei

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science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1489-1493页

作者： DU SaiSai1,2,BIAN BaoAn1,2,3,LIU Min1,2,4,FENG ZhaoQing5,6 & ZHANG FengShou1,2,6 1 Key Laboratory of Beam Technology and material Modification of Ministry of Education,College of nuclear science and Technology,beijing Normal university,beijing 100875,china 2 beijing Radiation Center,beijing 100875,china 3 School of science,Jiangnan university,Wuxi 214122,china 4 College of {13. and Technology,Guangxi Normal university,Guilin 541004,china 5 institute of Modern {13.,Chinese Academy of sciences,Lanzhou 730000,china 6 Center of Theoretical nuclear {13.,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china Key Laboratory of Beam Technology and material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China School of science Jiangnan University Wuxi 214122 China College of physics and Technology Guangxi Normal University Guilin 541004 China institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The shell effect is included in the improved isospin dependent quantum molecular dynamics model in which the shell correction energy of the system is calculated by using the deformed two-center shell model. A switch function is introduced to connect the shell correction energy of the projectile and the target with that of the compound nucleus during the dynamical fusion process. It is found that the calculated capture cross sections reproduce the experimental data quantitatively at the energy near the Coulomb barrier. The capture cross sections for reaction 35 80 Br + 82 208 Pb → 117 288 X are also calculated and discussed.

关键词： superheavy nuclei transport theory shell effect cross sections

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.

Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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science china Earth sciences 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2,DONG JinQuan2,GUO ZhaoJie3 & DENG Jun1 1 State Key Laboratory of Geological Processes and Mineral Resources,china university of Geosciences,beijing100083,china 2 Laboratory of nuclear Analysis Techniques,institute of High energy physics,Chinese Academy of sciences,beijing 100039,china 3 department of Geology,Peking university,beijing 100871,china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Laboratory of nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 289 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～250℃ for zircon fission track,and metallogenetic temperature of 120―350℃ in this ore *** three mineralization epochs have been identified,i.e.,289―276 Ma,232―200 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―13. Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～250℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 20 Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang

Simulation study of real-time monitor for BEPC-Ⅱ luminosity

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science china(Technological sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2,WU Jian2,XUE Zhen2,XU ZiZong2,HU Tao3,WANG YiFang3 & WANG XiaoLian2 1 College of material science and Technology,Nanjing university of Aeronautics and Astronautics,Nanjing 210016,china 2 department of Modern physics,university of science and Technology of china,Hefei 230026,china 3 institute of High energy physics,Chinese Academy of sciences,beijing 100049,china College of material science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China department of Modern physics University of Science and Technology of China Hefei China institute of High energy physics Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEPC-Ⅱ(beijing Electron Positron Collider,china).Photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEPC-Ⅱ Cherenkov detector radiative Bhabha

Influence of Yb^(3+) concentration on the upconversion luminescence of oxyfluoride material doped with Er^(3+)

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science china(physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3 1 institute of Optoelectronic Technology,Key Laboratory of Luminescence and Optical Information (beijing Jiaotong university),Ministry of Education,beijing 100044,china 2 department of physics,Chinese People’s Public Security university,beijing 100038,china 3 physics & engineering Mathematics department Faculty of Electronic engineering Menufiya university,Menouf 32952,Egypt 1. institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China2. Department of Physics Chinese People’s Public Security University Beijing 100038 China3. Physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya University Menouf 32952 Egypt

In this paper,a new upconversion luminescent material co-doped with Erbium and Ytterbium is reported. The upconversion luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3+ concentration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upconversion mechanism.

关键词： upconversion luminescence Er3+ Yb3+

Further research on high-spin structure in ^(161)Lu

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science china(physics,Mechanics & Astronomy) 2008年第3期51卷 315-320页

作者： LI YanXia1,2,YU ShaoYing1,2,4,SHEN CaiWan1,5,LI XiaoWei6 & CHEN YongShou3,4 1 School of science,Huzhou Teachers College,Huzhou 313.00,china 2 College of Mathematics,physics and Information engineering,Zhejiang Normal university,Jinhua 321000,china 3 china institute of Atomic energy,beijing 102413.china 4 institute of Theoretical physics,Chinese Academy of sciences,beijing 100080,china 5 Center of Theoretical nuclear physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 730000,china 6 department of physics,Chifeng university,Chifeng 024001,china School of science Huzhou Teachers College Huzhou 313000 China College of Mathematics Physics Information engineering Zhejiang Normal University Jinhua 321000 China china institute of Atomic energy Beijing 102413 China institute of Theoretical physics Chinese Academy of Sciences Beijing 100080 China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China department of physics Chifeng University Chifeng 024001 China

The two-dimensional total routhian surface (TRS) calculations were performed to probe into the triaxial superdeformed characteristics of a strongly populated band X2 in 161Lu. This band was identified as a triaxial superdeformed band by using our TRS method. We also got its formation mechanics,i.e. the neutron-shell correction energy plays a crucial role,while the rotating energy and the deformation-driving effect of high j intruder orbit i13.2 also play an additional role.

关键词： TRS method triaxial superdeformation formation mechanism

A DOMINANT DEFECT AT THE Si/SiO_2 INTERFACE IN MOS STRUCTURE

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science china Mathematics 1989年第12期32卷 1458-1468页

作者：陈开茅卢殿通 department of physics Peking University institute of low energy nuclear physics of beijing Normal university

The interface defects at the Si/SiO_2 interface in ρ-type silicon (111) MOS structures have been studied by the DLTS method. A dominant defect H_(it),(0.503) at the Si/SiO_2 interface has been found. Its characteristics are (i) the average hole ionization Gibbs free energy △G_p≥0.503 eV; (ii) by changing the gate bias when the distance from Fermi level to the top of Si valence band at the Si/SiO_2 interface is less than △G_p there is still the strong DLTS peak; (iii) its hole apparent activation energy increases with the dectease of the height of semiconductor surface potential barrier; and (iv) its hole capture process causes the multiexponential capacitance transience as a function of pulse width and the H_(it)(0.503) level are very difficult to be fully filled with the holes introduced by thepulst with alimited width. All above show that there is a continuous transition energy band between the energy bands of the covalent crystal silicon and the SiO_2 in the Si/SiO_2 systems formed by thermal oxidation; the dominant defect H_(it)(0.503) is distributed in the transition region, and the distance of H_(it)(0.503) level from the top of the valence band increases with the distance from the silicon surface.

关键词： interface defects MOS structure physics model of Si/SiO_2 interface.

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.

Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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Chinese science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, XIE Jianzhong1, FENG Songlin3, FAN Dongyu3, ZHANG Ying3, CAI Zhifang3, ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical engineering, Zhengzhou university, Zhengzhou 450052, china 2. department of physics, beijing Normal university, beijing 100875, china 3. High energy physics institute, the Chinese Academy of sciences, beijing 100080, china 4. Archaeology Research institute, Shanxi Province, Xian 710000, china Correspondence should be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical engineering Zhengzhou University Zhengzhou 450052 China department of physics Beijing Normal University Beijing 100875 China High energy physics institute Chinese Academy of Sciences Beijing 100080 China Archaeology Research institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 29 kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (1271—13.8 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—1279 A.D.) and the Jin Dynasty (1115—1234 A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析