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Study on forward modeling of through-casing resistivity logging

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Science china Earth Sciences 2008年第S2期51卷 207-211页

作者： GAO Jie1,LIU FuPing2,BAO DeZhou3,CHENG Xi3 & ZHANG YuLing4.1 china University of Petroleum,beijing 10224.,china 2 beijing {4. of Graphic Communication,beijing 102600,china 3 china Petroleum Logging CO. LTD.,Xi’an 710021,china 4.0} National Logging Corporation,beijing 100101,china china Univ Petr Beijing 102249 Peoples R China beijing Inst Graph Commun Beijing 102600 Peoples R China china Petr Logging CO LTD Xian 710021 Peoples R China china Natl Logging Corp Beijing 100101 Peoples R China

Through-casing resistivity logging (TCRL) is a new kind of logging method for formation evaluation,reservoir monitoring and saturation changes tracking. In this paper,the basic principle of TCRL is de-tailed,and the modified transmission line equation method (MTLEM) is first proposed in china. The MTLEM has been employed to simulate the responses of TCRL,on the basis of which,the effects of formation resistivity,cement and casing on the responses of TCRL are analyzed,and the signals in-duced in different formations are also calculated,which can help the design of TCRL tool and data processing and interpretation in china.

关键词： through-casing resistivity logging (TCRL) modified transmission line equation method (MTLEM) casing cement sheath

北京城市副中心0701街区D#地块住房百年住宅示范项目

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建筑实践 2024年第3期 96-103页

作者： china institute of Building Standard Design & Research Co., Ltd. 中国建筑标准设计研究院有限公司

北京城市副中心是规划建设疏解北京非首都功能、推动京津冀协同发展的历史性工程。项目对于落实首都城市战略定位、建设国际—流的和谐宜居之都,对于建设以首都为核心的世界级城市群,都具有十分重大而深远的意义。项目规划设计打破传统...

北京城市副中心是规划建设疏解北京非首都功能、推动京津冀协同发展的历史性工程。项目对于落实首都城市战略定位、建设国际—流的和谐宜居之都,对于建设以首都为核心的世界级城市群,都具有十分重大而深远的意义。项目规划设计打破传统封闭社区规划模式,以小街区密路网、开放式社区的设计骨架,用半围合式住宅,院落内外高差处理等设计手法打造和谐、有序而具有活力的多元示范住区。

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Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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Science china Earth Sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2, SHEN Ji3, ZHANG Yixiang2, ZHANG Peizhen4. WANG Sumin3, LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2, JIANG Shaoren2, LIU Xingqi3 & WANG Yong31. institute of Earth Environment, Chinese Academy of Sciences (CAS), Xi’an 710075, china 2. South china Sea institute of Oceanology, CAS, Guangzhou 510301, china 3. Nanjing institute of Geography and Limnology, CAS, Nanjing 210008, china 4. institute of Geology, china Earthquake Administration, beijing 100029, china 1. institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an 710075 China 2. South china Sea institute of Oceanology CAS Guangzhou 510301 China 3. Nanjing institute of Geography and Limnology CAS Nanjing 210008 China 4. institute of Geology China Earthquake Administration Beijing 100029 China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.

Simulating　Experimental　Investigation　on　the　Safety　of　Nuclear　Heating　Reactor　in　Loss－of－Coolant　Accidents

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Journal of Thermal Science 1996年第4期5卷 285-291页

作者： Zhanjie Xu(institute of Nuclear energy Technology, Tsinghua University, beijing, 100084. china) institute of Nuclear energy Technology Tsinghua University Beijing China

The 5MW low temperature nuclear heating reactor (NHR-5) is a new and advanced type of nuclear reactor developed by institute of Nuclear energy Technology (INET) of Tsinghua University of china in 1989. Its main loop is a thermal-hydraulic system with natural circulation. This paper studies the safety of NHR under the condition of loss-of-coolant accidents (LOCAs) by means of simulant experiments. First, the background and necessity of the experiments are presented, then the experimental system, including the thermal-hydraulic system and the data collection system, and similarity criteria are introduced. UP to now, the discharge experiments with the residual heating power (20% rated heating power) have been carried out on the experimental system. The system parameters including circulation flow rate, system pressure, system temperature, void fraction, discharge mass and so on have been recorded and analyzed. Based on the results of the experiments, the conclusions are shown as folios: on the whole, the reactor is safe under the condition of LOCAs, but the thermal vacillations resulting from the vibration of the circulation flow rate are disadvantageous to the internal parts of the reactor core.

关键词： nuclear heating reactor natural circulation LOCA safety.

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3, WANG Yong2, DU Xiaolong1, MEI Zengxia1, KONG Xianghe3, JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2, 4.1. State Key Laboratory for Surface Physics, institute of Physics, Chinese Academy of Sciences, beijing 100080, china 2. Laboratory of Electron Microscopy, institute of Physics, Chinese Academy of Sciences, beijing 100080, china 3. College of Physics and Engineering, Qufu Normal University, Qufu 273165, china 4. beijing University of Technology, beijing 100022, china 1. State Key Laboratory for Surface Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. College of Physics and Engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. beijing University of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 30 rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

Study on the changes of water cycle and its impacts in the source region of the Yellow River

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Science china(Technological Sciences) 2004年第z1期47卷 142-151页

作者： ZHANG Shifeng1, JIA Shaofeng1, LIU Changming1, CAO Wenbing2, HAO Fanghua3, LIU Jiuyu4.& YAN Huayun5 1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 2. china University of Geosciences, beijing 100083, china 3. beijing Normal University, beijing 100875, china 4. Bureau of Hydrology of Yellow River Conservancy Commission, Zhengzhou 4.0003, china 5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province, Xining 810001, china 1. institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China2. China University of Geosciences 100083 Beijing China3. Beijing Normal University 100875 Beijing China4. Bureau of Hydrology of Yellow River Conservancy Commission 450003 Zhengzhou China5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province 810001 Xining China

The water cycle in the source region of the Yellow River underwent great changes in the 1990s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 21st century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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Science china Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3, WU Yishi1, YUAN Gu3, AI Xicheng1, WANG Li4.& ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 2. School of Life Science and Technology, beijing institute of Technology, beijing 100081, china 3. College of Chemistry and Molecular Engineering, Peking University, beijing 100080, china 4. Center for Condensed Matter Physics, institute of Physics, Chinese Academy of Sciences, beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. School of Life Science and Technology Beijing Institute of Technology Beijing 100081 China 3. College of Chemistry and Molecular Engineering Peking University Beijing 100080 China 4. Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 32 ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

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电力变压器中的热工水力学问题及其实验研究

变压器 1997年第11期34卷 15-17页

作者： Ding Zhenxin (china institute of atomic energy,{4.) 中国原子能科学研究院

概述了电力变压器中的热工水力学问题及其实验研究的内容，阐述了热工水力学实验的发展方向及其作用。

关键词：电力变压器热工水力学实验

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. 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]Key Laboratory for Quantum Information and Measurements and Department of Physics Tsinghua University Beijing China [b]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 China [c]beijing Radiation Center Beijing China [d]Key Laboratory for atomic and Molecular Nano-Sciences Tsinghua University Beijing 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.