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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5 1. Key Laboratory For Quantum Information and Measurements of MOE, Department of Physics, Tsinghua university, beijing 100084,china 2. Department of Materials Science and Engineering, beijing normal university, beijing 100875, china 3. testing and analytical center, beijing normal university, beijing 100875,china 4. Department of Physics, beijing normal university, beijing 100875, china 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, beijing 100084,china 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. Department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. testing and analytical center Beijing Normal University 100875 Beijing China 4. Department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

改进的反Stokes能量传递对ErP5O14非晶中荧光动力学研究的影响

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物理学报 2011年第7期60卷 743-748页

作者：陈英陈晓波张会敏徐晓灵王策北京师范大学应用光学北京市重点实验室分析测试中心北京100875

本文通过建立不同浓度五磷酸盐非晶材料(ErxLa1-xP5O14)动力学过程的速率方程,特别是引入了改进系数exp{hcv珋k/kT}以区别能量传递Stokes过程和反Stokes过程,分别对Er0.01La0.99P5O14,Er0.1La0.9P5O14,和ErP5O14非晶材料中979.3nm,803.8nm和521.8nm光激发下所有能级的动力学过程在改进能量传递理论前后进行了比较,结果发现,当稀土离子间距较小时(如在ErP5O14非晶中),考虑能量传递Stokes和反Stokes过程差别对计算模拟非常重要,说明此时能量传递起到了关键性作用.而离子间距较大时,则几乎无影响.并且发现全浓度ErP5O14非晶材料在可见光激发下存在红外量子剪裁现象.且详细计算了有关的无辐射弛豫速率、自发辐射速率和能量传递速率,分析了有关的能量传递动力学过程,发现速率为239500s-1的{2H11/2→4I9/2,4I15/2→4I13/2}交叉能量传递是导致光激发2H11/2能级的红外量子剪裁现象的主要原因,该研究对于寻找高效率的太阳能电池材料很有意义.

关键词：反Stokes能量传递改进系数动力学过程五磷酸盐非晶红外量子剪裁

布居分支比模型——一种定性分析上转换效率的有效方法

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物理学报 2000年第6期49卷 1176-1179页

作者：陈晓波孟超王亚非马辉李美仙北京师范大学分析测试中心北京100875 首都经济贸易大学安全工程系北京100026

通过对在上转换的过程中起关键作用的是发动上转换的关键亚稳态的动力学因素的分析 ,建立了在连续激光激发下的定性分析上转换的“布居分支比 β”物理模型 :即上转换可以由关键亚稳态上的布居再次被激发至更高激发态的分支比 β来描述 ... 详细信息

通过对在上转换的过程中起关键作用的是发动上转换的关键亚稳态的动力学因素的分析 ,建立了在连续激光激发下的定性分析上转换的“布居分支比 β”物理模型 :即上转换可以由关键亚稳态上的布居再次被激发至更高激发态的分支比 β来描述 ;其特别的物理意义在于这种方法易于从总体上对上转换的性能有全面的定性的掌握 .还进一步论证了对于Er3+离子步进吸收上转换 ,石英、五磷酸盐等截止声子能量大于 10 0 0cm-1的材料的上转换发光约为氟化物的万分之一的原因是它们的多声子无辐射弛豫速率Wn 远大于自发辐射速率A ,而自发辐射A和多声子无辐射弛豫Wn 是同时起作用的 .还发现声子对于上转换的有益的价值的条件为Wn

关键词：布居分支比模型上转换陆续激光激发

实验室资质认定制度在大型仪器设备开放共享管理中的作用

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实验技术与管理 2011年第11期 350-354页

作者：梅建平冯建跃李崧东南大学分析测试中心浙江大学分析测试中心北京师范大学分析测试中心

提出了运用实验室资质认定制度的有关理念,从人员、设备、过程管理的角度,为解决高校大型仪器设备管理运行中出现的现实问题,为大型仪器设备的开放共享管理提出了一些思路与对策。

关键词：大型仪器设备资质认定开放共享

动物组织中阿莫西林残留的液相色谱分析方法研究

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色谱 2003年第6期21卷 541-544页

作者：刘媛丁岚谢孟峡刘素英杨清峰单吉浩北京师范大学分析测试中心北京100875 农业部畜禽产品质量监督检验测试中心北京100026

建立了反相高效液相色谱分析鸡肉、猪肉、猪皮、猪脂肪等动物组织样品中阿莫西林残留量的方法。对4种动物组织样品采用磷酸盐缓冲溶液提取、三氯乙酸沉淀蛋白、固相萃取净化和富集、1,2,4 三唑氯化汞衍生化。研究了样品在C18柱上的保... 详细信息

建立了反相高效液相色谱分析鸡肉、猪肉、猪皮、猪脂肪等动物组织样品中阿莫西林残留量的方法。对4种动物组织样品采用磷酸盐缓冲溶液提取、三氯乙酸沉淀蛋白、固相萃取净化和富集、1,2,4 三唑氯化汞衍生化。研究了样品在C18柱上的保留行为和阿莫西林的衍生化条件。衍生物采用高效液相色谱法分离,外标法定量分析,标准曲线的线性相关系数为0 9997,线性范围为8 6～860μg/L。动物组织样品中阿莫西林的加标回收率为70.9%～86 8%,相对标准偏差为3 2%～16 4%,最低检出限低于10μg/kg。该分析方法具有良好的重现性,批内、批间定量结果的相对标准偏差均小于10%。

关键词：动物组织阿莫西林残留量液相色谱分析方法固相萃取衍生反应药物残留

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

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Science china(Physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2 1. Applied Optics beijing Area Major Laboratory, Analysis and testing center, beijing normal university, beijing 100875, china 2. Peking university, Physics School, beijing 100871, china Applied Optics beijing Area Major Laboratory Analysis testing center Beijing Normal University Beijing 100875 China Physics School Peking University Beijing 100871 China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2(Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2(Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 23.040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials

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Journal of Materials Science & Technology 1999年第4期15卷 315-319页

作者： Shaojun LIU(Department of physics, beijing normal university, beijing 100875, china)Xiaobo WEI(Department of Physics, Liuzhou College of Education, Liuzhou 545005, china)Zhaodou CHEN Jun CAI and Benkun MA(Department of Physics, beijing normal university, beijing normal Univ Dept Phys Beijing 100875 Peoples R China Liuzhou Coll Educ Dept Phys Liuzhou 545005 Peoples R China

In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.

关键词： Rev Li Chen From the Green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body

Approach to synthesis of novel chiral 3-chloro-2(5H)- furanone and its application in asymmetric reactions

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Chinese Science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. Department of Chemistry, Tonghua Teacher’s College, Tonghua 134002, china 2. Department of Chemistry, beijing normal university, beijing 100875, china Department of Chemistry Tonghua Teacher’s College Tonghua China Department of Chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3-chloro-2-(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13 C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2,3i(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3-chloro-2-(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

Theorems for testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied Science School, university of Science and Technology beijing, beijing 100083, china) Applied Science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat