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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 {4.,Chinese Academy of Sciences,beijing 10003.,China 3.{4. 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 14. *** 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 14.―3.0℃ and retention temperature of ～250℃ for zircon fission track,and metallogenetic temperature of 120―3.0℃ in this ore *** three mineralization epochs have been identified,i.e.,289―276 Ma,23.―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 14.―13. Ma,109―97 Ma and 64.Ma,which means age at about 100℃ after the *** three epochs lasted 14. 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

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A NEW BIFUNCTIONAL CHELATING AGENT α,ε-N,N'-BIS(L-CYSTEINYL)-L-LYSINE FOR RADIOLABELLING OF MONOCLONAL ANTIBODIES WITH TECHNETIUM-99M

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Chinese Chemical Letters 1991年第4期2卷 285-288页

作者： Bi Zhong LI Yuan Fang LIU Yong Hui WU department of technical physicsYun Hua YE department of Chemistry,{4. university,beijing 100871

α,ε-N,N'-bis(L-cysteinyl)-L-lysine was synthesized and char- acterized for the first *** was then employed as a bifunctional chelating agent to chelate technetium-99m and subsequently conjugated to fragment F(ab')_2... 详细信息

关键词： A NEW BIFUNCTIONAL CHELATING AGENT L-CYSTEINYL L-LYSINE FOR RADIOLABELLING OF MONOCLONAL ANTIBODIES WITH TECHNETIUM-99M N,N BIS

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The refined theory of deep rectangular beams for symmetrical deformation

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Science China(physics,Mechanics & Astronomy) 2009年第6期52卷 919-925页

作者： GAO Yang1 & WANG MinZhong2 1 College of Science, China Agricultural university, beijing 100083. China 2 State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace Engineering,{3.,{4., China College of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence and Complex Systems and department of Mechanics and Aerospace Engineering Peking University Beijing 100871 China

Based on elasticity theory, various one-dimensional equations for symmetrical deformation have been deduced systematically and directly from the two-dimensional theory of deep rectangular beams by using the Papkovich-Neuber solution and the Lur'e method without ad hoc assumptions, and they construct the refined theory of beams for symmetrical deformation. It is shown that the displacements and stresses of the beam can be represented by the transverse normal strain and displacement of the mid-plane. In the case of homogeneous boundary conditions, the exact solutions for the beam are derived, and the exact equations consist of two governing differential equations: the second-order equation and the transcendental equation. In the case of non-homogeneous boundary conditions, the approximate governing differential equations and solutions for the beam under normal loadings only and shear loadings only are derived directly from the refined beam theory, respectively, and the correctness of the stress assumptions in classic extension or compression problems is revised. Meanwhile, as an example, explicit expressions of analytical solutions are obtained for beams subjected to an exponentially distributed load along the length of beams.

关键词： deep rectangular beams the refined theory symmetrical deformation the Papkovich-Neuber solution the Lur’e method

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EFFECT OF MOLECULAR WEIGHT OF PEO ON THE STRUCTURE AND PROPERTIES OF PDMAEMA/PEO HYDROGELS

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Chinese Journal of Polymer Science 2006年第1期24卷 35-40页

作者： Zhu-gen Liu Min Yi Mao-lin Zhai and Hong-fei Ha department of Applied Chemistry and The Key Laboratory of Polymer Chemistry and physics of Ministry of Education,College of Chemistry & Molecular Engineering,peking {3.,{4. 100871,China peking Univ Coll Chem & Mol Engn Dept Appl Chem Beijing 100871 Peoples R China peking Univ Coll Chem & Mol Engn Minist Educ Key Lab Polymer Chem & Phys Beijing 100871 Peoples R China

A new kind of binary hydrogels composed of poly（dimethylaminoethylmethacrylate）（PDMAEMA） and poly（ethylene oxide）（PEO） with varying weight average molecular weights （M^-w = 5 × 10^4. 1 × 10^5 and 2.5 × 10^6） were prepared by У-irradiation technology. The properties of PDMAEMA/PEO hydrogels obtained were evaluated in terms of gel fraction, gel strength, thermal characterization and swelling behavior. The gel strength and swelling degree of the hydrogels could be improved obviously after adding PEO into the PDMAEMA system, while the degree of improvement decreased with increasing M^-w of PEO. The temperature sensitivity of PDMAEMA/PEO was retained only in the sample with PEO of M^-w = 5 × 10^4. and the pH sensitivity was retained in samples with PEO of M^-w = 5 × 10^4.and 1 × 10^5. When DMAEMA/PEO mixtures containing PEO of M^-w = 5 × 10^4.were irradiated, the main reaction could be the cross-linking of DMAEMA, and the linear PEO molecular chains could penetrate into the cross-linked network of PDMAEMA. With increasing M^-w of PEO, some side reactions were induced, such as grafting of DMAEMA onto PEO molecules, the scission or cross-linking of PEO.

关键词： Poly(dimethylaminoethylmethacrylate) Poly(ethylene oxide) Molecular weight Binary hydrogels Irradiation.

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X（3.72） and Bound State Problem of D0*0（0 D*0）

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原子核物理评论 2009年第S1期 16-21页

作者： LIU Yan-rui1,LIU Xiang2,3.DENG Wei-zhen2 (1 Institute of High Energy physics,Chinese Academy of Sciences,beijing 10004.,China 2 department of physics,{4. university,beijing 100871,China 3.Centro de Física Terica,Departamento de Física,Universidade de Coimbra,P-3.04.516,Coimbra,Portugal)

We have performed a dynamical calculation of the bound state problem of D0D*0 by considering the pion and sigma meson exchange potential. Our preliminary analysis disfavors the molecular interpretation of X(3.72) if we use the experimental D*Dπ coupling constant g=0.59 and a reasonable cutoff around 1 GeV,which is the typical hadronic scale. In contrast,there probably exists a loosely bound S-wave BB* molecular state. Such a molecular state would be rather stable since its dominant decay mode is the radiative decay through B*→Bγ.

关键词： X(3.72) bound state molecule

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Micro-mechanical analysis of dynamic processes of nanomanipulation

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Science China(physics,Mechanics & Astronomy) 2004年第z1期47卷 88-92页

作者： HU Jie, ZHANG Yujun, LI Peng, WANG Hui, HUANG Lan & HU YuanzhongState Key Laboratory of Tribology, Tsinghua university, beijing 100084. China department of {3., Tsinghua university, beijing 100084. China College of Chemistry and Molecular Engineering, peking university, beijing 100871, China 1. State Key Laboratory of Tribology Tsinghua University 100084 Beijing China 2. department of physics Tsinghua University 100084 Beijing China 3. College of Chemistry and Molecular Engineering Peking University 100871 Beijing China

In this study, atomic force microscope (AFM) tips are used as tools to cut and manipulate carbon nanotubes on various surfaces. The lateral forces acting on AFM tips during manipulation are also recorded and analyzed from the perspective of micro-mechanics. It is found that differences in surface conditions can lead to obvious increase in micro-friction between nanotube and substrate. And also due to rehybridization, carbon nanotubes present excellent resilience when undergoing different degrees of strain. Finally, carbon nanotubes can complexly deform from elastic stage to plastic stage before complete rupture.

关键词： nanomanipulation, carbon nanotubes, AFM tips, micro-mechanics.

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Supersymmetric WKB Approximation of Anharmonic Potential V(γ)=aγ~2+bγ-4.cγ-6

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Communications in Theoretical physics 2006年第7期46卷 37-38页

作者： QIAN Shang-Wu,~1 MIAO Chun-Hui,~1 and GU Zhi-Yu~2 ~1physics department, peking university,{3., China ~2physics department, Capital Normal university, beijing 10003., China

This article uses the supersymmetric WKB approximation to obtain the approximate energy levels and wave functions of the anharmonic potential V(r) = ar~2+br+crin order to tesify the correctness between [Phys. Lett. A ... 详细信息

关键词： supersymmetric WKB approximation energy level wave function

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Progress Toward Integrated Devices of High Tc Superconductors

Progress Toward Integrated Devices of High Tc Superconductor...

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第三届青年超导会

作者： WANG Shiguang department of physics,peking {3.,{4. 100871

This article reviews the development of high T superconducting devices in the recent *** innovation in the deposition and the microfabrication technologies for the oxide thin films has spurred the evolution of the Josephson weak *** researchers in the field have surmounted many of the initial hurdles,working towards the complex high-temperature superconducting electronics.

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The numerical method for three-dimensional impact with friction of multi-rigid-body system

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Science China(physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2, LIU Caishan2 & CHEN Bin2 1. beijing Institute of Graphic Communication, beijing 102600, China 2. department of Mechanics & Engineering Science,{3.,{4., China beijing Institute of Graphic Communication Beijing 102600 China department of Mechanics & Engineering Science Peking University Beijing 100871 China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

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A quantification model for apoptosis in mouse embryos in the early stage of fetation

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Science China(Life Sciences) 2009年第10期52卷 922-927页

作者： WANG PengFei1, FU JianHua1, MA WanYun1, CHEN DieYan1, Lü DanYu2 & BAI WenJia3.1 Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry, department of physics, Tsinghua university, {3. 100084. China 2 department of Anatomy & Histology and Embryology, School of Basic Medical Sciences peking university Health Science Center, {3. 100083. China 3.department of Automation, Tsinghua university, {3. 100084. China 1. Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry Department of Physics Tsinghua University Beijing 100084 China 2. department of Anatomy & Histology and Embryology School of Basic Medical Sciences Peking University Health Science Center Beijing 100083 China 3. department of Automation Tsinghua University Beijing 100084 China

Apoptosis is the most important inducement and modulator for embryos in the early stage of fetation, i.e. after the 8-cell stage, mostly the morula and blastula stage, to proceed to the stage of nonlinear development. Using a two-photon laser scanning microscopy (TPLSM) system, we obtained 3.dimensional (3.) fluorescent images of preimplantation mouse embryos. A model for quantification was established. The statistical results for the spatial location of apoptosis bodies in embryos was obtained following image processing, as well as investigation of the kinetics of apoptosis. It was found that most (70%) apoptosis occurred in the trophectoderm, and the departure between the centroid and geometric center of embryos had a step transition when embryos developed into the 3.-cell stage, which was consistent with the theoretical prediction that the blastocele would induce a symmetry break of the distribution of cells in embryos.

关键词： apoptosis preimplantation mouse embryo TPLSM quantification model

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