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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

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Science china Earth Sciences 2004年第10期47卷 886-895页

作者： TANG Liangjie1,2, JIA Chengzao3, PI Xuejun4, CHEN Suping1,2, WANG Zhiyu5. XIE Huiwen4 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry, beijing 102.49, china 2. Basin & Reservoir Research Center, university of petroleum, beijing 102.49, china 3. Petro{5. Company Limited, beijing 100011, china 4. Tarim Oilfield Company, Petro{5. Company Ltd., Kurle 841000, china 5. department of geology, university of petroleum, beijing 102.49, china 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry 102249 Beijing China 2. Basin & Reservoir Research Center University of Petroleum 102249 Beijing China 3. Petrochina Company Limited 100011 Beijing China 4. Tarim Oilfield Company PetroChina Company Ltd. 841000 Kurle China 5. department of geology University of Petroleum 102249 Beijing China

The salt beds of Lower Tertiary developed in the mid-segment of Kuqa foreland fold belt, northern Tarim basin. They considerably controlled structural deformation of the belt. Ac- cording to the field observation, seismic profile interpretation and drilling data, three different structural styles of supra-salt, intra-salt and sub-salt occurred in the Kuqa foreland fold belt. Su- pra-salt structural styles mainly include thrust faults and fault-related sags. Intra-slat structural styles essentially are salt-pillows, intra-salt faults and folds, and salt weld structures. Sub-salt structural styles mainly consist of imbricated thrust faults, duplex structures, pop-up and fault-related folds. It is indicated that great differences exist among supra-salt, intra-salt and sub-salt structures of Kuqa foreland fold belt. The salt-related structures were formed in the same structural stress field. The dynamic mechanism of the salt-related structures is mainly associated with gravitation, compression and plastic flow of salt beds.

关键词： salt-related structural style, supra-salt structure, intra-salt structure, sub-salt structure, Kuga foreland fold belt.

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science china Earth Sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5.& LI Zhen6 1. SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075. china 2. department of Urban and Resources Sciences, Nanjing university, Nanjing 210093, china 3. department of Earth Sciences, Nanjing university, Nanjing 210093, china 4. department of Geography, Shaanxi Normal university, Xi’an 710062, china 5. Institute of geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 6 department of Geography, Qinghai Normal university, Xining 810008, china 7. Graduate School of the Chinese Academy of Sciences, beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of Sciences Beijing 100039 China 2. department of Urban and Resources Sciences Nanjing University Nanjing 210093 China 3. department of Earth Sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25.visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth Sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2 & ZHOU Hui3 1. Laboratory of Material in the Earth’s Interior, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 5.0002, china 2. department of geology, china university of Geosciences, {5. 100083, china 3. department of geology, Peking university, {5. 100871, china 1. Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. department of geology China University of Geosciences 100083 Beijing China 3. department of geology Peking University 100871 Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12―200 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12 h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 85.℃, varying the annealing time (12―200 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12 h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 85.℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5.vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 85.℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.

Application of C5.C13 light hydrocarbons in depositional environment diagnosis

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Progress in Natural Science:Materials International 2008年第9期18卷 1129-1137页

作者： Peirong Wanga,b,, Guanjun Xu a,c, Tingrong Xiaoc, Dajiang Zhanga,c, Bin Zhanga,c a Key Laboratory of petroleum Geochemistry, china National petroleum Corporation, beijing 100083, china b {5. of Organic Geochemistry, Yangtze university, Jingzhou 434023, china c Central Laboratory of petroleum geology, Research Institute of petroleum Exploration and Development, Petrochina, beijing 100083, china Key Laboratory of petroleum Geochemistry China National Petroleum Corporation Beijing 100083 China department of Organic Geochemistry Yangtze University Jingzhou 434023 China Central Laboratory of petroleum geology Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

Based on the geological background and Gammacerane/C31H(S + R) ratios, source rock depositional environments of the studied oil samples (194) from 13 oilfields were classified into three groups according to salinity:saline-lacustrine facies, fresh to brackish lacustrine facies (including limnetic facies), and semi-saline to saline facies (including marine facies of the Tarim Basin).C5.C13 compound groups in the crude oils were separated by GC, and about 286 compounds were qualitatively *** geochemical application of the C6-C13 compound groups and their ratios between each group with individual carbon number was *** studies show that (1) C6-C13 compound groups and their ratios in the crude oils could serve as new reliable parameters for oil-oil correlation because the C6-C13 light fractions are the major oil component, especially in light oil or condensate, in which they account for almost 90% of the whole oil;(2) the compound groups of C7 light hydrocarbons in oils derived from difierent depositional environments with difierent salinity have difierent characteristics;(3) C6-C13 compound groups and ratios may be afiected by other factors such as maturity, but they are mainly controlled by salinity of depositional waters.

关键词： Light hydrocarbons Crude oil Depositional environment Salinity

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Atomic phase diagram

Progress in Natural Science:Materials International 2004年第2期14卷 17-22页

作者： LI Shichun*(Materials department, university of petroleum, Dongying 25.061, china) Univ Petr Dept Mat Dongying 257061 Peoples R China

Based on the Thomas-Fermi-Dirac-Cheng model, atomic phase diagram or electron density versus atomic radius diagram describing the interaction properties of atoms of different kinds in equilibrium state is developed. Atomic phase diagram is established based on the two-atoms model. Besides atomic radius, electron density and continuity condition for electron density on interfaces between atoms, the lever law of atomic phase diagram involving other physical parameters is taken into account, such as the binding energy, for the sake of simplicity.

关键词： TFDC model atom phase diagram two-atoms model electron density atomic radius.

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 Normal university, beijing 100875. china Testing and Analytical Center, beijing Normal university, beijing 100875. china department of Physics, beijing Normal 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.

Gas formation mechanism of marine carbonate source rocks in china

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Science china Earth Sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2, ZHANG Mingjie3, WANG Hongjun1, WANG Yunpeng4 & QIN Yong5.1. Research Institute of petroleum Exploration & Development, Petrochina, beijing 100083, china 2. Petrochina Exploration & Production, beijing 100011, china 3. department of geology, Lanzhou university, Lanzhou 730000, china 4. Guangzhou Geochemical Institute, Chinese Academy of Sciences, Guangzhou 5.0640, china 5. china university of Mining and Technology, Xuzhou 221000, china 1. Research Institute of petroleum Exploration & Development 100083 PetroChinaBeijin China 2. Petrochina Exploration & Production 100011 Beijing China 3. department of geology Lanzhou University 730000 Lanzhou China 4. Guangzhou Geochemical Institute Chinese Academy of Sciences 510640 Guangzhou China 5. china university of Mining and Technology 221000 Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the Chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.

Carbon isotope ratios of C_(4) plants in loess areas of North china

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Science china Earth Sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3, HAN Jiamao 2, ZHOU Liping3, XIONG Xiaogang4, TAN Ming2, WU Zhenhai5.& PENG Jun6 1. department of Plant Nutrition, china Agricultural university, beijing 100094, china 2. Institute of {5. and Geophysics, Chinese Academy of Sciences, beijing 100029, china 3. College of Environmental Sciences, MOE Laboratory for Earth Surface Processes, Peking university, beijing 100871, china 4. Institute of Botany, Chinese Academy of Sciences, beijing 100093, china 5. Northwest Sci-Tech university of Agriculture and Forestry, Yangling 712100, china 6. Network Center, china Agricultural university, beijing 100094, china 1. department of Plant Nutrition China Agricultural University Beijing 100094 China 2. Institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. Institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech university of Agriculture and Forestry Yangling 712100 China 6. Network Center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13)C) of 89 C_4 plant samples were determined fromthe loess area in North china. δ^(13)C values vary between -10.5.er thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13)C values of C_4 plants show a slight decreasingtrend. The δ^(13)C values of C_4 plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3 species.

关键词： C4 plants, carbon isotope ratios, loess area.