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CRYSTALLIZATION OF METALLIC GLASS Zr_70Cu_30 UNDER HIGH PRESSURE

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 137-140页

作者： SHEN Dejiu WU Haoquan Yanshan University,Qinhuangdao,china SHEN Zhongyi CHEN Guiyu YIN Xiujun institute of physics,Academia Sinica,Beijing,china Iectrurer,Department of Materials engineering,Yanshan University,Qinhuangdao 066004,china Yanshan Univ Qinghuangdao China

Crystallization temperature of the metallic glass Zr_(70)Cu_(30),observed by X-ray diffraction analysis,may be increased about 20℃,the superior limit of increase range of the temperature is about 30℃,under high pres... 详细信息

关键词： metallic glass Zr_(70)CU_(30) crystallization high pressure

Radiation Effect of Neutrons in a Reactor on Polyurethane

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Journal of Wuhan University of Technology(Materials Science) 2010年第6期25卷 966-968页

作者：黄玮 institute of Nuclear physics and Chemistry China Academy of Engineering Physics

The radiation effect of neutrons in a reactor on polyurethane was *** gases produced by irradiated samples were analyzed by gas chromatography,and the dynamic mechanical and compression properties of the samples were also *** positron annihilation lifetime of irradiated samples was measured at room temperature in *** experimental results indicate that gas chromatography is a powerful tool to quantitatively analyze the gas products from neutron-irradiated polyurethane and characterizes the chemical changes in the *** the changes in microstructure determined from the PAL correlate well with the measurements of the mechanical properties by dynamic mechanical analysis（DMA）.

关键词： neutrons in a reactor polyurethane radiation effect

Containerless solidification of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) glass-forming alloy in drop tube

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Chinese Science Bulletin 2002年第20期47卷 1700-1703页

作者： LI Gong, SUN Liling & WANG WenkuiCollege of Material Sciences and engineering, Yanshan University, Qinhuangdao 066004, china Center for Condensed Matter physics, institute of physics, Chinese Academy of Sciences, Beijing 100080, china National Microgravit Coll. of Mat. Sci. and engineering Yanshan University Qinhuangdao 066004 China Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China National Microgravity Laboratory Chinese Academy of Sciences Beijing 100080 China

Droplets of Zr41Ti14Cu12.5Ni10Be22.5 glass forming alloys with different sizes are solidified in a drop tube containerless processing. Glass transition behavior, crystallization kinetics, and the phase evolution during annealing of the Zr41Ti14Cu12.5Ni10Be22.5 glassy spheres are investigated. The experimental results indicate that the apparent activation energy of the glass transition (Eg=435.5 kJ/mol), and the activation energy of the main crystallization reaction (Ep1 = 249.6 kJ/mol) are obviously different from those of bulk glass samples prepared by water quenched (Eg=559.1 kJ/mol and Ep1=192.5 kJ/mol). The difference is discussed in the view point of the atomic configuration of the liquid state of the metallic glass and nucleation mechanism.

关键词： ZrTiCuNiBe alloy containerless processing activation energy drop tube.

Study on Doped DLC Films Deposited by Pulse Arc Technology

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稀有金属材料与工程 2011年第S4期40卷 243-245页

作者： Zhao Dongcai,Ren Ni,Ma Zhanji,Xiao Gengjie,Wu Shenghu Science and Technology on Surface engineering Laboratory,Lanzhou institute of physics,Lanzhou 730000,china Lanzhou Inst Phys Sci & Technol Surface Engn Lab Lanzhou 730000 Peoples R China

The bonds of metal and carbon don't form in metal-doped DLC films which be deposited by pulse arc facility for the condition of low temperature and alternate *** hardness and internal stress decreases as the doped content increase,the good luck is that the stress decreases more *** the friction coefficient increase as the doped content *** the Si was doped,Si-C bonds has been formed,and the hardness of films keep constant as the Si content under 6.7%,so the properties of mechanic have been improved by doping *** Si doped target be used in film deposition process,atoms of Si and C were deposited at one time,so that the Si-C bond formed.

关键词： Diamond like carbon doped pulse arc deposition mechanics properties

A SQP optimization method for shimming a permanent MRI magnet

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Progress in Natural Science:Materials International 2009年第10期19卷 1439-1443页

作者： Zhe Jina,Xing Tangb,Bin Menga,Donglin Zu b,Weimin Wanga,a institute of Quantum Electronics,School of Electronics engineering and Computer Science,Peking University,Beijing 100871,china b institute of Heavy Ion physics,Beijing Key Laboratory of Medical physics and engineering,School of physics,Peking University,Beijing 100871,china institute of Quantum Electronics School of Electronics Engineering and Computer Science Peking University Beijing 100871 China institute of Heavy Ion physics Beijing Key Laboratory of Medical Physics and Engineering School of Physics Peking University Beijing 100871 China

Based on the sequential quadratic programming(SQP) method,a new approach is presented in this paper to gain a uniform magnetic field for a permanent MRI magnet with biplanar ***,the adopted shimming piece is modeled as a magnetic dipole moment to calculate its effect on the background field over the imaging region of ***,the SQP method is utilized to determine the ideal solution for the shimming ***,the ideal solution is discrete,and the quantization error control technique is used for special *** new method helps to reduce the inhomogeneity from 1234.5 ppm to 21.4 ppm over a 36 cm diameter spherical volume(DSV),within hours in practical shimming work.

关键词： Magnetic resonance imaging(MRI) Field shimming Sequential quadratic programming(SQP) Permanent MRI magnet

Suppression　of　Interference　Speckles　in　the　Uniform　Line　Focus　System　of　Segmented　Wedge　Array　Using　Phase－disturbed　Plate

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Chinese Journal of Lasers 1996年第4期B5卷 363-370页

作者： LIU Zhongyong ZHENG Ruilun(physics Department of South-West Normal University,Chongqing630715,china)SUI Zhan(Laboratory for Laser Fusion,institute of Nuclear physics and Chemistry ,china Academy of engineering physics,Chendu 610003, china)LU Baida CAI South West Normal Univ Chongqing China

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ＳｕｐｐｒｅｓｓｉｏｎｏｆＩｎｔｅｒｆｅｒｅｎｃｅＳｐｅｃｋｌｅｓｉｎｔｈｅＵｎｉｆｏｒｍＬｉｎｅＦｏｃｕｓＳｙｓｔｅｍｏｆＳｅｇｍｅｎｔｅｄＷｅｄｇｅＡｒｒａｙＵｓｉｎｇＰｈａｓｅ－ｄｉｓｔｕｒｂｅｄＰｌａｔｅ￥ＬＩＵＺｈｏｎｇｙｏｎｇ；ＺＨＥＮＧ...

关键词： phase-disturbed plate phase modulation time smoothing interference

Theory study of shapes in ^(187,189)Tl nuclei

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Science china(physics,Mechanics & Astronomy) 2009年第6期52卷 818-821页

作者： LIU YanXin1, YU ShaoYing1,2,3, SHEN CaiWan1,5 & DONG YongSheng1,2,4 1 School of Science, Huzhou Teachers College, Huzhou 313000, china 2 School of Science and Information engineering, Zhejiang Normal University, Jinhua 321000, china 3 institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100080, china 4 Department of physics, Jining Teachers College, Jining 012000, china 5 Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000, china School of Science Huzhou Teachers College Huzhou China School of Science and Information engineering Zhejiang Normal University Jinhua China institute of Theoretical physics Chinese Academy of Sciences Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China Department of physics Jining Teachers College Jining China

The nuclear shapes of 187,189Tl were investigated theoretically in this work. The total routhian surface (TRS) calculations were performed for N=106 and 108 isotopes of thallium (Z=81). The single-particle energies were obtained from the deformed Woods-Saxon potential, with the Lipkin-Nogami (LN) treatment of pairing. It is found that the collective oblate rotation coexists with the high-K prolate rotation. Superdeformed prolate rotation is included in this calculation.

关键词： nuclear shape oblate rotation prolate rotation

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science china Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3, WU Yishi1, YUAN Gu3, AI Xicheng1, WANG Li4 & ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, china 2. School of Life Science and Technology, Beijing institute of Technology, Beijing 100081, china 3. College of Chemistry and Molecular engineering, Peking University, Beijing 100080, china 4. Center for Condensed Matter physics, institute of physics, Chinese Academy of Sciences, Beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China School of Life Science and Technology Beijing Institute of Technology Beijing China College of Chemistry and Molecular engineering Peking University Beijing China Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32 ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

The complex variable reproducing kernel particle method for elasto-plasticity problems

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 954-965页

作者： CHEN Li1 & CHENG YuMin2 1 Department of engineering Mechanics,Chang’an University,Xi’an 710064,china 2 Shanghai institute of Applied Mathematics and Mechanics,Shanghai University,Shanghai 200072,china Department of engineering Mechanics Chang'an University Xi'an 710064 China

On the basis of reproducing kernel particle method(RKPM),using complex variable theory,the complex variable reproducing kernel particle method(CVRKPM) is discussed in this *** advantage of the CVRKPM is that the correction function of a two-dimensional problem is formed with one-dimensional basis function when the shape function is *** the CVRKPM is applied to solve two-dimensional elasto-plasticity *** Galerkin weak form is employed to obtain the discretized system equation,the penalty method is used to apply the essential boundary *** then,the CVRKPM for two-dimensional elasto-plasticity problems is formed,the corresponding formulae are obtained,and the Newton-Raphson method is used in the numerical *** numerical examples are given to show that this method in this paper is effective for elasto-plasticity analysis.

关键词： meshless method reproducing kernel particle method(RKPM) complex variable reproducing kernel particle method(CVRKPM) correction function elasto-plasticity