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Dense coding scheme using superpositions of Bell-states and its NMR implementation

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Science China(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, Department of Physics, Tsinghua University, beijing 100084. China center for Quantum Information, Tsinghua University, beijing 100084. China Department of Materials Science and Engineering, beijing {4. University, beijing 100875, China testing and analytical center, beijing {4. University, beijing 100875, China Department of Physics, beijing {4. University, beijing 100875, China 1. Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University 100084 Beijing China 2. center for Quantum Information Tsinghua University 100084 Beijing China 3. Department of Materials Science and Engineering Beijing Normal University 100875 Beijing China 4. testing and analytical center Beijing Normal University 100875 Beijing China 5. Department of Physics Beijing Normal University 100875 Beijing China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

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 {2., beijing {4. 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 4.0.1, 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 = 2..04.×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.

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 134.02. China 2. Department of Chemistry, beijing normal University,{2., 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.

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,{2., China)Xiaobo WEI(Department of Physics, Liuzhou College of Education, Liuzhou 54.005, 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

Mechanisms of invasive population establishment and spread of pinewood nematodes in China

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Science China(Life Sciences) 2009年第6期52卷 587-594页

作者： XIE BingYan1,CHENG XinYue2.SHI Juan3,ZHANG QingWen4.DAI ShuMing1,CHENG Fei Xue2.& LUO YouQing3 1 Institute of Vegetables and Flowers,Chinese Academy of Agricultural Sciences,beijing 100081,China 2.beijing {2. University,beijing {4.,China 3 beijing Forestry University,beijing 100083,China 4.Chinese Agricultural University,beijing 100094.China 1. Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 China 2. beijing normal University Beijing 100875 China 3. beijing Forestry University Beijing 100083 China 4. Chinese Agricultural University Beijing 100094 China

This paper summarizes the results of our study of the pinewood nematode(Bursaphelenchus xylophi-lus).By population genetic analysis,it was determined that there was no genetic bottle caused by the founder effect and genetic drift in the Chinese invasive *** invasions with large amounts of nematodes from different sources led to rich genetic diversity in the invasive *** high genetic diversity in the invasive process may be one of the genetic mechanisms in its successful *** testing interspecies competition,it was shown that,with high fecundity and a strong competitive ability,*** outcompeted the native species *** in the natural ecosystem during the invasion *** displacement may be one of the ecological mechanisms of ***'s *** addition,an unequal interspecific hybridization with intro-gress was in favor of the invasive species which also accelerated the replacement of *** by *** structures,functions and evolutions of a few important genes that are closely related to the ecological adaptation of pinewood nematodes were studied to explore the molecular mechanism of its ecological ***,the resistance and resilience mechanism of the pine ecosystem invaded by pinewood nematodes was also *** results of these studies uncovered a portion of the genetic and ecological mechanisms of PWN's successful invasion and laid a foundation for further study to obtain a comprehensive interpretation of the mechanisms of the nematode *** results also provided a scientific basis for effectively controlling the occurrence and spread of pine wilt disease which is caused by *** aspects requiring further investigation are considered.

关键词： pinewood nematode bioinvasion genetic diversity ecological adaptation resistance resilience

Characterization of the interaction between human serum albumin and flavonol

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Characterization of the interaction between human serum albu...

Determination and confirmation of the thyreostats by matrix solid phase dispersion and GC-MS

中国化学会第十三届有机分析与生物分析学术会议

作者： XIE Meng-xia , XU Xiao-yun, LIU Yuan, QIN Chuan (analytical & testing {2., beijing {4. University, beijing 100875)

＜正＞Morin and quercetin are active naturally occurring flavonols and possess various biological and pharmacological effects. The interactions of morin and quercetin with human serum albumin （HSA） have been comparatively investigated by the fluorescence, UV absorption and Fourier transform infrared spectroscopic approaches. Fluorescence data revealed the presence of one specific binding site on HSA for morin and quercetin, and their

关键词： Morin Quercetin Flavonol Human serum albumin Fourier transform infrared spectroscopy Fluorescence UV absorption Secondary structure

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Determination and confirmation of the thyreostats by matrix ...

Spectroscopic and photometric observations of unidentified ultraviolet variable objects in the GUVV-2.Catalog

中国化学会第十三届有机分析与生物分析学术会议

作者： ZOU Qiong-hui, LIU Yuan, XIE Meng-xia , HAN Jie (analytical & testing {2., beijing {4. University, beijing 100875)

＜正＞A rapid and simple method for determination and confirmation of the thyreostats in milk, urine and animal tissues has been developed. The samples were extracted and purified by matrix solid phase dispersion （MSPD） with silica gel as the solid support, and the thyreostats including tapazole, 2.thiouracil, 6-methyl-2.thiouracil, 6-propyl-2.thiouracil and 6-phenyl-2.thiouracil have been separated and detected by gas chromatography-mass

关键词： Thyreostats Matrix solid-phase dispersion Gas chromatography-mass spectrometry Milk Urine, animal tissues

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Research in Astronomy and Astrophysics 2011年第7期11卷 833-842页

作者： You Li Jing Wang Jian-Yan Wei Xiang-Tao He Department of Astronomy Beijing Normal University Beijing 100875 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

An NUV-optical diagram composed from sources from the second Galaxy Evolution Explorer（GALEX） Ultraviolet Variability（GUVV-2. Catalog provides us with a method to tentatively classify the unknown GUVV-2.sources by their NUV-optical *** the purpose of testing the correctness and generality of the method,we carry out a program on the spectroscopic observations of the unidentified GUVV-2.*** spectroscopic identification of these 37 sources are 19 type-A to-F stars,10 type-G to-K stars and 7 M dwarf stars together with an *** also present the light curves in the R-band for two RR Lyrae star candidates selected from the NUV-optical diagram,both of which undergo cyclic *** their light curves and colors,we classify them as RR Lyrae *** confirm the re-sults,we show a color-color diagram for the 37 newly identified spectroscopic objects compared with previously identified ones,which are consistent with our previous re-sults,indicating that the ultraviolet variable sources can initially be classified by their NUV/optical color-color diagram.

关键词： stars:variables:general—galaxies:active—methods:observational—ultraviolet emission

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钠蒸气参量四波混频紫外辐射的产生

中国激光 1997年第9期24卷 833-836页

作者：方允孙寅官李晓文汪凯戈尤秉信北京师范大学物理系北京师范大学分析测试中心广东韶关大学物理系

记录并分析了钠原子蒸气形成近４Ｄ能级双光子共振参量四波混频产生的３３０ｎｍ信号，描述了信号强度随实验条件变化的规律，确定了最强辐射条件。

关键词：双光子共振参量四波混频钠蒸气紫外辐射激光