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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 {3. for Quantum Information, Tsinghua university, beijing 100084. china Department of Materials Science and Engineering, beijing normal university, beijing 100875, china testing and analytical {3., beijing normal university, beijing 100875, china Department of Physics, beijing normal university, beijing 100875, china 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 100875 China testing and analytical center Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 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.

Influence of Ethylene Glycol on the Formation of Calcium Phosphate Nanocrystals

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Journal of Materials Science & Technology 2003年第6期19卷 628-630页

作者： Yi ZUO, Yubao LI, Jie WEI and Yonggang YANResearch center for Nano-Biomaterials, analytical and testing center, Sichuan{4., Chengdu 610064. china Res. Ctr. for Nano-Biomaterials Analytical and Testing Ctr. Sichuan Univ. Chengdu 610064 China

A synthesis route of using calcium hydroxide Ca(OH)2 with ethylene glycol solvent and orthophosphoric acid (H3.O4. as reagents is described. Three ratios of ethylene glycol to distilled water 1:0, 1:1 and 0:1 are used as diluting media for Ca(OH)2. Crystals of different morphology and composition are formed under weak alkaline circumstance at pH 7.0-8.0. Acicular calcium phosphate nanocrystals are prepared in pure ethylene glycol while rod-like calcium phosphate nanocrystals form in pure distilled water. The nanograde size of the former is smaller than that of the latter. Calcium-deficient apatite (CDAP) is obtained with a Ca/P molar ratio of 1.66. Therefore, it was deduced that the usage of ethylene glycol solvent could influence the formation of calcium phosphate crystal lattice.

关键词： Acicular nanocrystals Calcium phosphate Ethylene glycol solvent Weak alkaline circumstance

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3.& FENG Hao4.1. Institute of Physics, College of Chemical Engineering, Sichuan university, Chengdu 610065, china 2. Institute of Theoretical Physics, Xihua normal university, Nanchong 63.002, china 3. Department of Physics, china Oceanography university, Qingdao 266003. china 4. College of Physics, Sichuan university, Chengdu 610065, china Institute of Physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China College of Physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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,{3., beijing 100875, china 2. Peking university, Physics School, beijing 100871, china Applied Optics beijing Area Major Laboratory Analysis and testing center Beijing Normal University Beijing China Physics School Peking University Beijing 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 63..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.)→3.1(Pr3.)], the 789.0 nm upconver-sion excitation transition 1G4.Pr3.)→3.2(Pr3.), and the 803.7 nm upconversion excitation transition 3.6(Pr3.)→1D2(Pr3.). The upconversion excitation transition 1G4.Pr3.)→1I6(Pr3.) is strong because its oscillator strength f = 23.04.×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.

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{4.,beijing 100875,china 3.beijing Forestry university,beijing 100083.china 4.Chinese Agricultural university,beijing 100094.china Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing China beijing normal university Beijing China beijing Forestry university Beijing China Chinese Agricultural university Beijing 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

First Preparation and Reactivity of γ-Oxo Vinyliminophosphorane

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Chinese Chemical Letters 1997年第4期8卷 289-290页

作者： Ming Wu DING Wen Fau HUNG Hai Yang TO(Institute of Organic Synthesis,Central china normal university,Wuhan, 4.3}070)Tian Jie WU({3. of Analysis and {4.,Central china normal university,Wuhan,4.3}070) Institute of Organic Synthesis Central China Normal University Wuhan 430070 China center of Analysis and testing Central China Normal University Wuhan 430070 China

The γ-oxo vinyliminophosphorane 3.was prepared for the first time from the Staudinger reaction of vinyl azide 2 and triphenylphosphine. The reaedvity of 3.was studied

关键词： First Preparation and Reactivity of Oxo Vinyliminophosphorane

PRECIPITATION IN A Cu-BASED SMA　

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中国有色金属学会会刊：英文版 1995年第1期5卷 71-75页

作者： Chang Fenglian Wang Shidong Wang Yurui Zhao Liancheng (analytical and testing center, Southeast {3., Manjing 210018) SE UNIV CTR ANALYT & TESTINGNANJING 210018PEOPLES R CHINA

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ＰＲＥＣＩＰＩＴＡＴＩＯＮＩＮＡＣｕ－ＢＡＳＥＤＳＭＡＣｈａｎｇ；ＦｅｎｇｌｉａｎＷａｎｇ；ＳｈｉｄｏｎｇＷａｎｇ；ＹｕｒｕｉＺｈａｏ；Ｌｉａｎｃｈｅｎｇ（ＡｎａｌｙｔｉｃａｌａｎｄＴｅｓｔｉｎｇＣｅｎｔｅｒ，ＳｏｕｔｈｅａｓｔＵｎｉｖｅｒｓｉｔｙ，...

关键词： crystal structure shape memory second phase

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 54.005, china)Zhaodou CHEN Jun CAI and Benkun MA(Department of Physics, beijing normal university, Department of Physics Beijing Normal University Beijing 100875 China Department of Physics Liuzhou College of Education Liuzhou 545005 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

Separation of Hydrophobic Neutral Compounds by Microemulsion Electrokinetic Chromatography

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Chinese Chemical Letters 1998年第11期9卷 0-0页

作者： Xiao Yun FU Xiu Zhu XU Jian De LU (analytical and testing center, Zhejiang {3., Hangzhou 3.0027) analytical and testing center Zhejiang University Hangzhou 310027 China

Microemulsion electrokinetic chromatography (MEEKC) was developed for the separation of hydrophobic neutral compounds. The effects of core phase and co-surfactant on the separations were investigated. Under the selected condition, good resolutions were obtained for the test mixtures. The separation efficiencies were higher than 105 theoretical plates per metre.

关键词： Microemulsion electrokinetic chromatography hydrophobic compounds