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物理学报 1997年第7期46卷 1267-1272页

作者：刘宇峰曾谨言北京大学物理系

分析表明，对于二维氢原子和各向同性谐振子，从径向Ｓｃｈｒｄｉｎｇｅｒ方程的因式分解导出的升降算子与ＲｕｎｇｅＬｅｎｚ矢量等价．这表明径向方程能够因式分解。

关键词： R-L矢量升降算子量子论二维氢原子

Synergic Extraction of Uranium Thiocyanate by the Ternary System of ABC Species Composed of PMBP-TBP-（C6H5）4.sCI

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Chemical Research in Chinese Universities 1985年第1期 15-20页

作者： Yi Min,Chen Dingfong,Mou Xiru and Wang Wenqing (department of Technical physics,peking university,{4.)

The synergic extraction of uranyl thiocyanate with binary system of 1-phenyl-3-methy1～4.benzoylpyrazolone-5 (PMBP)and tributyl phosphate(TBP)or tetraphenylarsonium chloride [(C6H5)4.sCl] and ternary system of PMBP-TBP-(C6H5 )4.sCl was *** was an obvious synergic effect of uranium (VI)from thiocyanate medium in binary and ternary *** formation of a ternary extracted complex,(C6H5)4.sUO2.(NCS)A2 TBP,was confirmed by the slope method.A method was first proposed for the calculation of the equilibrium constant of ternary synergic reaction.

关键词： PMBP As C6H5 Synergic Extraction of Uranium Thiocyanate by the Ternary System of ABC Species Composed of PMBP-TBP

Rapid spin-lattice relaxation time mapping incorporating fiip angle calibration in quantitative magnetic resonance imaging

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Progress in Natural Science:Materials International 2008年第9期 1077-1081页

作者： Zhongliang Zu a, Qi Liu a, Yanming Yu a, Song Gaob, Shanglian Bao a, a The Key Laboratory of Medical physics and Engineering, peking university, beijing 100871, China b Medical physics{4., Health Science Center of peking university, beijing 100083, China

Driven equilibrium single pulse observation of T1 (DESPOT1) is a rapid spin-lattice relaxation constant (T1) mapping technique in magnetic resonance imaging (MRI).However, DESPOT1 is very sensitive to fiip angle (FA) inhomogeneity, resulting in T1 ***, a five-point DESPOT1 method is proposed to reduce the sensitivity to FA inhomogeneity through FA measurement and *** and in vivo experiments are performed to validate the *** a result, a rapid and accurate T1 mapping is acquired by using the proposed five-point DESPOT1 method.

关键词： Spin-lattice relaxation time Flip angle inhomogeneity Flip angle calibration

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基于电光聚合物的表面等离激元调制器

物理学报 2008年第9期57卷 5893-5898页

作者：陈建军李智张家森龚旗煌北京大学物理系人工微结构和介观物理国家重点实验室北京100871

基于电光聚合物,提出了一种结构简单,尺寸小,效率高的表面等离激元(SPP)调制器.该调制器采用M-Z干涉仪结构的金属波导,金属周围是均匀极化后的电光聚合物,通过在金属波导两臂间加电压对聚合物折射率进行调制,折射率调制再通过M-Z干涉仪... 详细信息

基于电光聚合物,提出了一种结构简单,尺寸小,效率高的表面等离激元(SPP)调制器.该调制器采用M-Z干涉仪结构的金属波导,金属周围是均匀极化后的电光聚合物,通过在金属波导两臂间加电压对聚合物折射率进行调制,折射率调制再通过M-Z干涉仪结构转化为对金属波导中SPP强度的调制.通过求解金属波导附近的电场分布,并结合SPP场分布的特点,在理论上说明了这种结构可以通过外加电压有效地调制金属波导输出端SPP的强度,调制所需的半波电压约为2.8 V.

关键词：表面等离激元电光调制电光聚合物

γ Radiative Decays to Light Quark Jets and Color Octet Mechanism

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Communications in Theoretical physics 2006年第12期 1017-1022页

作者： GAO Ying-Jia,~1 ZHANG Yu-Jie,~1 and CHAO Kuang-Ta~(1,2) 1 department of physics, peking university, beijing 100871, China 2 China Center of Advanced Science and Technology (World Laboratory), Belling 100080, China

We study radiative decays of T to light quark jets in nonrelativistic QCD by taking both the color singlet and color octet b5 operators into consideration. The cut for quark jet energy and cut for the angle between two quark jets are introduced. The sensitivity to the soft and collincar singularities in the loop integrals are greatly reduced by these cuts. With the jet energy cut of about 1 GeV, and the jet angle cut of about 36°, the branching ratio for γ→γqqis found to be 8.2×10;from color singlet contributions. The color octet contributions could be much larger than that of color singlet, depending on the estimate of the color octet matrix elements. This process may provide a new test for the color octet mechanism in nonrelativistic QCD.

关键词： radiative decay jet color octet

Nanofabrication by two-photon polymerization with femtosecond laser pulses

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Nanofabrication by two-photon polymerization with femtosecon...

第一届激光加工前沿国际会议

作者： Qihuang Gong,Hong Yang,Yan Li and Yunfeng Xiao department of physics &State Key Laboratory for Mesoscopic physics,peking{4.,beijing,100871,China

Direct laser writing by two-photon polymerization with femtosecond laser pulses has become a powerful tech-nique for creating fully 3Dnanostructures,such as photonic crystals,metamaterials,waveguide-based devices,laps on a chip and *** systematically investigate the polymerization of suspended nanorods to find the way to reduce the featuresize to～15nm,to compensate for the shrinkage and tapering,and to control the aspect ratio of cross-section,which enable us to fabricate single-mode dielectric-loaded surface plasmon-polariton nanowaveguides and high quality optical whispering gallery *** feature-size of suspended nanorods has been reduced toλ/*** with sub-25nm width are produced by controlling the incident laser power and the laser focus scan speed up to 700m/*** on re-polymerization between two structures close to each other,the feature-size is further reduced to～15nm,which demonstrates the potential for three-dimensional nanofabrication with high spatial resolution.

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来源： cnki会议评论

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星际甲醇(CH_3OH)脉泽

天文学进展 1997年第3期15卷 247-253页

作者：周昇刘永翊吴月芳中国科学院射电联合实验室上海分部

简要综述了近年来对于星际CH3OH脉泽的观测和研究成果，对CH3OH脉泽的性质从分类、生成区域及分布、辐射特性、运动状况等方面做了介绍，并阐明了理论上对其时变特性、激发机制及河外脉泽的探讨，最后对两种类型的CH3OH脉泽作了对比和... 详细信息

简要综述了近年来对于星际CH3OH脉泽的观测和研究成果，对CH3OH脉泽的性质从分类、生成区域及分布、辐射特性、运动状况等方面做了介绍，并阐明了理论上对其时变特性、激发机制及河外脉泽的探讨，最后对两种类型的CH3OH脉泽作了对比和讨论。

关键词：脉泽星际介质运动学动力学甲醇

超导球在磁场中的受控运动——迈斯纳效应演示实验方案

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物理 2002年第1期31卷 52-54页

作者：刘彦良北京大学物理系本科二年级北京100871

用相互垂直的数个线圈构造空间磁场的极小值点 ,通过计算机改变线圈中的电流 ,使此极小值点做受控运动 ,从而实现通过悬浮于该处的超导球对迈斯纳效应的动态展示 .

关键词：迈斯纳效应动态演示超导球磁场受控运动实验方案

A mathematical method for the de-dispersion of the pulsar profile

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Science China(physics,Mechanics & Astronomy) 2010年第S1期53卷 228-230页

作者： YUAN JianPing1,2,WANG Na1,WU XinJi3 & ESAMDIN Ali1 1 Urumqi Observatory,National Astronomical Obsevatories,Urumqi 830011,China 2 Graduate university of the Chinese Academy of Sciences,beijing 10004.,China 3 department of Astronomy,peking university,beijing 100871,China 1. Urumqi Observatory National Astronomical Obsevatories Urumqi 830011 China 2. Graduate university of the Chinese Academy of Sciences Beijing 100049 China 3. department of Astronomy Peking University Beijing 100871 China

This paper presents a mathematical method for de-dispersion of average pulsar *** applied this method to four dispersed pulsar *** results revealed that this method significantly removed the dispersion broadening and ... 详细信息

关键词： pulsar dispersion measure interstellar medium