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Magnetic Field Effects on Quantum-Dot Spin Valves

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Communications in Theoretical physics 2009年第3期51卷 555-562页

作者： GAO Jin-Hua,~1 SUN Qing-Feng,~1 and XIE Xin-Cheng~(1,2)1 Beijing National Lab for Condensed Matter physics and Institute of physics, Chinese Academy of Sciences,Beijing 100080, china2 department of physics, Oklahoma State University, Stillwater, Oklahoma 74078, USA Beijing National Lab for Condensed Matter physics and Institute of physics Chinese Academy of Sciences Beijing 100080 China department of physics Oklahoma State University Stillwater Oklahoma 74078 USA

We study the magnetic field effects on the spin-polarized transport of the quantum dot (QD) spin valve inthe sequential tunneling regime. A set of generalized master equation is derived. Based on that, we discuss the collinearand noncollinear magnetic field effects, respectively. In the collinear magnetic field case, we find that the Zeeman splittingcan induce a negative differential conductance (NDC), which is quite different from the one found in previous *** has a critical polarization in the parallel arrangement and will disappear in the antiparallel configuration. In thenoncollinear magnetic field case, the current shows two plateaus and their angular dependence is analyzed. Althoughsometimes the two current plateaus have similar angular dependence, their mechanisms are different. Our formalism isalso suitable for calculating the transport in magnetic molecules, in which the spin splitting is induced not by a magneticGeld but by the intrinsic magnetization.

关键词： spin value spintronics quantum dot

Excitation Spectrum of Spin-1 Bosonic Atoms in Mort Insulating Phase

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Communications in Theoretical physics 2006年第1期 87-94页

作者： HOU Jing-Min~(1,2,+) TIAN Li-Jun~31 department of physics,Southeast University,Nanjing 210096,china2 Theoretical physics Division,Nankai Institute of Mathematics,Nankai University,Tianjin 300071,china3 department of physics,Shanghai University,Shanghai 200436,china

The effective action for spin-1 bosonic atom in an optical lattice is *** quasiparticle and quasiholedispersions are calculated for different cases by using a functional integral *** all cases,the excitation spectraar... 详细信息

关键词： collective excitations optical lattice Mott-insulating phase spinor atoms

BEHAVIOUR OF VACANCY INFLUENCE DURING DIFFUSION IN METALS

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Acta Metallurgica Sinica(English Letters) 1992年第6期5卷 395-401页

作者： ZHANG Sanhong HE Xinlai CHU Youyi KE Jun (T.Ko) University of Science and Technology Beijing,china Doctor,department of Materials physics,University of Science and Technology Beijing,Beijing 100083 Beijing Univ of Science and Technology Beijing China

The effects of vacancies on diffusion of interstitial and substitutional atoms as well as interaction between them in metals were *** the interstitial alloy,a coupling between interstitial atoms and vacancy is interre... 详细信息

关键词： vacancy diffusion Fick's law

A Study on Uptake and Localization of Merocyanine 540 (MC540) in Murine Myeloid Leukemia Cells by Confocal Laser Scanning Microscopy (CLSM)

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Chinese Journal of Lasers 2000年第3期9卷 35-41页

作者： J. Y. Chen-1 N. H. Cheung-2 S. C. Chen-2, M. C. Fung-3 W. N. Leung-4 N. K. Mak- 4+ ( -1department of physics, Fudan University, Shanghai 200433, china -2department of physics, Hong Kong Baptist University, Hong Kong, china -3department of Bi 复旦大学上海香港浸会大学香港香港大学香港

The intracellular localization of merocyanine 540 (MC540), a photosensitizer commonly used in the photo-inactivation of leukemia cells, was studied using confocal laser scanning microscopy. It was found for the first time that MC540 not only localized in the plasma membrane but also in the cytoplasm and the nuclear membrane of the murine myeloid leukemia M1 and WEHI 3B (JCS) cells. Exposure of MC540 treated leukemia cells to light under conditions that could cause photobleaching did not cause the redistribution of cell-bound MC540. Rapid localization of MC540 in the cytoplasm was observed 5 minutes after exposure of leukemia cell to MC540, indicating that MC540 could promptly be internalized by these two leukemia cell lines. In contrast, localization of MC540 was limited only to the plasma membrane of erythrocytes. These results suggest that the binding pattern of MC540 is cell type dependent and may be related to the efficacy of photosenitization in photodynamic therapy.

关键词： merocyanine 540 Confocal Laser Scanning Microscopy Myeloid Leukemia cell

Effect of ambient oxygen pressure on structural, optical and electrical properties of SnO_2 thin films

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Rare Metals 2006年第6期25卷 693-696页

作者： ZHAO Songqing ZHOU Yueliang WANG Shufang ZHAO Kun HAN Peng Beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China department of Mathematics and physics China University of Petroleum Beijing 102249 China

PolycrystaUine SnO2 thin films were deposited on sapphire substrates at 450℃ under different ambient oxygen pressures by pulsed laser deposition technique. The effect of ambient oxygen pressure on the structural, optical and electrical properties of SnO2 thin films was studied. X-my diffraction and Hall measurements show that increasing the ambient oxygen pressure can improve crystallization of the films and decrease resistivity of the films. A violet emission peak centered at 409 nm was observed from photoluminescence measurements for SnO2 films under deposition ambient oxygen pressure above 5 Pa, which is related to the improvement of crystalline of the films.

关键词： tin oxide pulsed laser deposition oxygen pressure PLD resistivity

Investigation on the 773 K isothermal section of La-Fe-Sn ternary systems by X-ray powder diffraction

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Rare Metals 2010年第6期29卷 567-571页

作者： CHEN Xiang ZHUANG Yinghong CHEN Yungui Key Laboratory of Nonferrous Metal and New Processing Technology of Materials (Ministry of Education of china) Guangxi University Nanning 530004 China department of physics and Electronic Information Engineering Neijiang Teachers College Neijiang 641002 China department of Metallic Materials Engineering Sichuan University Chengdu 610065 China

The 773 K isothermal section of the La-Fe-Sn ternary system was investigated and constructed by X-ray powder diffraction（XRD）.The existence of two reported ternary intermetallic compounds,La6Fe13Sn and La3FeSn6,is confirmed in this *** with other R-Fe-Sn phase diagrams（R = Pr and Sm）,the binary alloys Fe3Sn and Fe5Sn3 are not *** compound Fe3Sn2 was observed from the XRD pattern of Fe3Sn2 samples,but it is not an equilibrium phase at 773 K and decomposes into Fe and FeSn phases completely for a longer heat treated *** to now,the crystal structure data of La2Sn3 has not been reported,so the X-ray pattern of La2Sn3 was only *** phase relationship for this compound was drawn by a dotted line.

关键词： intermetallics quenching phase diagrams X-ray diffraction.

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时空混沌的单向耦合同步

物理学报 2002年第12期51卷 2702-2706页

作者：张旭沈柯河北工业大学理学院应用物理系长春理工大学理学院物理系长春130022 长春理工大学理学院物理系

以耦合映象格子模型为例 ,提出利用单向耦合驱动时空混沌的同步方案 ,并进行了数值分析 .结果表明 ,适当地选择耦合驱动强度因子和均衡系数 ,两个时空混沌系统可以达到准确同步 .通过计算最大条件Lyapunov指数 ,给出了可实现时空混沌同... 详细信息

以耦合映象格子模型为例 ,提出利用单向耦合驱动时空混沌的同步方案 ,并进行了数值分析 .结果表明 ,适当地选择耦合驱动强度因子和均衡系数 ,两个时空混沌系统可以达到准确同步 .通过计算最大条件Lyapunov指数 ,给出了可实现时空混沌同步的最小耦合强度以及最小耦合强度与系统参数之间的关系曲线 .数值模拟还证明 ,此方法工作鲁棒 .

关键词：时空混沌同步单向耦合最大条件Lyapunov指数数值模拟耦合映象格子模型

Progress in multi-waveband observations of supernova remnants

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Progress in Natural Science:Materials International 2008年第9期18卷 1057-1062页

作者： Xuejuan Yang a,b, Fangjun Lua, Wenwu Tian c,d,* a Particle Astrophysics Center, Institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049, china b department of Astronomy, Beijing Normal University, Beijing 100875, china c National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, CAS, Beijing 100012, china d department of physics & Astronomy, University of Calgary, Alberta, Canada T2N 1N4 Particle Astrophysics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences 20A Datun Road Chaoyang District CAS Beijing 100012 China department of physics & Astronomy University of Calgary Alberta Canada T2N 1N4

The development of observational techniques has enriched our knowledge of supernova remnants. In this paper, we review the main progresses in the last decade, including new discoveries of supernova remnants and the associated (rare type of) pulsars, nucleosynthesis, the interaction between supernova remnants and molecular clouds, dust in the supernova remnants, shock physics, and cosmic ray accelerations.

关键词： Supernova remnant Observations

EFFECT OF Ce ON OXIDATION BEHAVIOUR OF Ni_3Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 1997年第1期10卷 74-78页

作者： T.H Xi Z.X. Yuan and Z.S. Yu (Research Institute of Wuhan Iron & Steel (Group) Company, Wuhan 430080, china)(department of Materials, Wuhan Yejin University of Science and Technology, Wuhan 430081, china)(department of Materials physics, Beijing Universi Research Inst of Wuhan Iron and Steel (Group) Co Wuhan China

The effect of Ce on the oxidation behaviour of undoped and B-doped Ni3 Al has been studied. Ce can refine Al2O3 grains produced in the course of oxidation of polycrystalline Ni3Al, accelerate the diffusion of oxygen along Al2O3 grain boundaries,and promote the growth of Al2O3 grains. As a result, the quantity of less-protective NiO decreases. The oxidation resistance of 0.011% Ce-doped alloy is the best of all Ce-doped Ni3Al alloys. Because B is benefitial to the formation of Al2O3 and Ce can refine Al2O3 grains, the oxidation resistance of the alloy containing both B and Ce is the best.

关键词： Ni_3Al Ce oxidation