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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,{2. 2. Department of Materials Science and Engineering, {5. Normal university, {5. 100875. china 3. Testing and Analytical center, {5. Normal university, {5. 100875.{2. 4. Department of Physics, {5. Normal university, {5. 100875. china 5. Key Laboratory For atomic and molecular nanosciences, tsinghua university, beijing 100084,{2. Key Laboratory For Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China Department of Materials Science and Engineering Beijing Normal University Beijing 100875 China Testing and Analytical center Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China Key Laboratory for Atomic and molecular nanosciences Tsinghua University Beijing 100084 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 2.+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

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural Science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2., Zhang Yong3 and Long Guilu1,2.1. Key Laboratory for Atomic and molecular nanosciences, and Department of Physics,{2.,{5., china 2. center of Quantum Information Science and Technology, tsinghua National Laboratory for information Science and Technology,{5., china 3. Institute of Physics, School of Sciences, beijing university of Posts and Telecommunications, beijing 100876, china) Key Laboratory for Atomic and molecular nanosciences and Department of Physics Tsinghua University Beijing 100084 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4,5.1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, Institute of Low Energy Nuclear Physics, beijing Normal university, beijing 100875. china 2.beijing Radiation center, beijing 100875. china 3 Laboratory of Optical Physics, Institute of Physics, Chinese Academy of Sciences, beijing 100080, china 4 Key Laboratory of Advanced Materials of the Ministry of Education, Department of Materials Science and Engineering, tsinghua university, beijing 100084, china 5.beijing National center for Electron Microscopy, tsinghua university, beijing 100084, china Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation center Beijing China Laboratory of Optical Physics Institute of Physics Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China beijing National center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4+, and Mn3+ ions are partly converted into Mn2. and Mn4+ due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4+ was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4+; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4+. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

Multiparty quantum secret sharing of classical and quantum messages

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Progress in Natural Science:Materials International 2007年第1期17卷 26-31页

作者： CHEN Pan, DENG Fuguo and LONG Guilu ( Key Laboratory for Quantum Information and Measurements, and Department of Physics, tsinghua university, beijing 100084,{2. Key Laboratory of Beam Technology and Material Modification, MOE, Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, beijing Normal university, beijing 100875.{2. beijing Radiation center, beijing 100875.{2. Key Laboratory for Atomic and molecular Nano-Sciences, tsinghua university, beijing 100084,{2.) Key Laboratory for Quantum Information and Measurements and Department of Physics Tsinghua University Beijing 100084 China Key Laboratory of Beam Technology and Material Modification MOE Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation center Beijing 100875 China Key Laboratory for Atomic and molecular Nano-Sciences Tsinghua University Beijing 100084 China

A scheme for multiparty quantum secret sharing of classical and quantum messages is proposed by using entanglement swapping. This scheme can distribute not only the classical information but also the quantum informati... 详细信息

关键词： quantum secret sharing classical message quantum message EPR pair.

Simulation of freezing and melting of soil on the northeast Tibetan Plateau

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Chinese Science Bulletin 2011年第20期56卷 2145-2155页

作者： XIA Kun 1,2.3,LUO Yong 2.4,5.& LI WeiPing 2.1 Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 10002.,{5. 2.ational Climate {2.,{5. Meteorological Administration,beijing 100081,{5. 3Graduate university of Chinese Academy of Sciences,beijing 100049,{5. 4 {2. for Earth System Science,{15. university,beijing 100084,{5. 5.ey Laboratory of Earth System Numerical Simulation,Ministry of Education,beijing 100084,{5. Institute of Atmospheric Physics Chinese Academy of Sciences National Climate center China Meteorological Administration Graduate university of Chinese Academy of Sciences center for Earth System Science Tsinghua University Key Laboratory of Earth

Using observational data spanning the period from February to December 2.09 and recorded at the Suli station in Qinghai Province,the land-surface model CLM3.0 was employed to simulate the freezing and melting of *** results indicate that the simulated soil temperature is higher than the observed soil temperature and the ultimate thawing date is earlier than the observed date during the melting *** the freezing period,the simulated soil temperature is lower than the observed soil temperature and the ultimate freezing of the deep soil is earlier than that ***,the simulation of freezing is better than that of melting,and the simulation of a shallow layer is better than that of a deeper *** the original CLM3.0,it is assumed that frozen soil begins to melt when the soil temperature exceeds 0C,which is inconsistent with *** critical freeze-thaw temperature was calculated according to thermodynamics equations and the freeze-thaw condition was *** this work,the melting rate for frozen soil was reduced using the modified scheme,and the simulated soil temperature was lowered. Meanwhile,the refreezing of soil during the melting season was well simulated and more closely matched ***,it was found that the rates of melting and freezing differ,with the former being slower than the latter,but refreezing during the melting season is rather quick.

关键词：土壤温度冻结期青藏高原东北部模拟融化观测数据热力学方程表面模型

Tissue-specific expression of GFP reporter gene in germline driven by GATA-2.promoter and enhancers in zebrafish

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Chinese Science Bulletin 2000年第1期45卷 31-34,97页

作者： MENG Anming & LIN Shuo1. Laboratory of Developmental Biology, Department of Biological Sciences and Biotechnology, tsinghua university, beijing 100084,{2. 2. Institute of molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912. USA Laboratory of Developmental Biology Department of Biological Sciences and Biotechnology Tsinghua University Beijing China Institute of molecular Medicine and Genetics Medical College of Georgia Augusta USA

GATA-2. a transcription factor, is expressed in several types of blood cells and in the central nervous system (CNS), and regulates the differentiation of these cells. We have obtained five zebrafish transgenic germlines that carry and express the green fluorescent protein (GFP) gene ligated to various 5. flanking sepuences of zebrafish GATA-2.gene. The spatial pattern of GFP expression varies, mainly depending on which regulatory sequence is used, among the germlines. In some of the germlines, the expression of GFP is restricted to the CNS and the enveloping layer (EVL) cells, while in some other lines GFP is observed only in the CNS. it is noted that the intensity of GFP in the transgenic fish remain unchanged after a six-generation passage of the transgenes. The transgenic fish could find its uses in the future in generating tissue-specific, even cellspecific mutant fish and in functional study of related genes through transgenesis.

关键词： zebrafish transgenic GATA-2 GFP germline.

Crystallization and preliminary X-ray studies of porcine kidney aminoacylase Ⅰ

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Chinese Science Bulletin 1997年第20期42卷 1750-1752页

作者： ZHAOHaiyan, MENGWuyi, LIN Zhengjiong and ZHOU Haimeng1. National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, beijing 100101, china 2. Department of Biological Science and Biotechnology,{2., beijing 100084, china National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing China Department of Biological Science and Biotechnology Tsinghua University Beijing China

AMINOACYLASE Ⅰ（ACY-1）（E. C. 3. 5. 1. 14 ） participated in amino acid metabolism existingin mammalian kidney and microorganisms, and catalyzes reversible hydrolysis of acylaminoacids. ACY-1 consists of 772.amino acids, and the molecular weight is 85.5.0 daltons. It is adimeric metalloprotein having two Zn2. in the molecule. The nucleotide and the amino acid se-quence of porcine and human ACY-1 have been determined. The nucleotide sequence and

关键词： aminoacylase I crystallization preliminary crystallography.

Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2. DENG Jinfu3, ZHOU Su3, LI Jinfa4, XIAO Qinghui1,5. WU Zongxu6 & LIU Cui3 1. Institute of Geology, Chinese Academy of Geological Sciences, beijing 100037, china 2. Development and Research {2., china Geological Survey, beijing 100037, china 3. china university of Geosciences, beijing 100083, china 4. china university of Geosciences, Wuhan 430074, china 5. Information {2. of Ministry of Land and Resources, beijing 100812. china 6. Institute of Geology, State Seismological Bureau, beijing 10002., china Institute of Geology Chinese Academy of Geological Sciences Beijing China Development and Research center China Geological Survey Beijing China china university of Geosciences Beijing China china university of Geosciences Wuhan China Information center of Ministry of Land and Resources Beijing China Institute of Geology State Seismological Bureau Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

In flight MTF monitoring and compensation for CCD camera on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2.3, LI Xiaoying1,2.4, MIN Xiangjun5. YU Tao1,2. SUN Jijuan5. ZENG Yong1,2.4, XU Hua1,2.& GUO Ding2.6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal university, beijing 100101, china 2. The center for National Spaceborne Demonstration, beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. Graduate university of Chinese Academy of Sciences, beijing 100039, china 5. china center for Resource Satellite Data and Application, beijing 100830, china 6. university of Electronic Science and Technology of china, Chengdu 61005., china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University The center for National Spaceborne Demonstration

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5.for 45. directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 45. axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.