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| 1 | A study of interaction between surface water and groundwater using environmental isotope in Huaisha River basin显示文摘The surface water and groundwater are important components of water cycle, and the interaction between surface water and groundwater is the important part in water cycle research. As the effective tracers in water cycle research, environmental isotope and hydrochemistry can reveal the interrelationships between surface water and groundwater effectively. The study area is the Huaisha River basin, which is located in Huairou district, Beijing. The field surveying and sampling for spring, river and well water were finished in 2002 and 2003. The hydrogen and oxygen isotopes and water quality were measured at the laboratory. The spatial characteristics in isotope and evolution of water quality along river lines at the different area were analyzed. The altitude effect of oxygen isotope in springs was revealed, and then using this equation, theory foundation for deducing recharge source of spring was estimated. By applying the mass balance method, the annual mean groundwater recharge rate at the catchment was estimated. Based on the groundwater recharge analysis, combining the hydrogeological condition analysis, and comparing the rainfall-runoff coefficients from the 1960s to 1990s in the Huaisha River basin and those in the Chaobai River basin, part of the runoff in the Huaisha River basin is recharged outside of this basin, in other words, this basin is an un-enclosed basin. On the basis of synthetically analyses, combining the compositions of hydrogen and oxygen isotopes and hydrochemistry, geomorphology, geology, and watershed systems characteristics, the relative contributions between surface water and groundwater flow at the different areas at the catchments were evaluated, and the interaction between surface water and groundwater was re- vealed lastly. | SONG Xianfang1, LIU Xiangchao1, 2, XIA Jun1, YU Jingjie1 & TANG Changyuan1, 3 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographical Sciences and Natural Re- sources Research, Chinese Academy of Sciences, Beijing 100101, China 2. College of River and Ocean, Chongqing Jiaotong University, Chongqing 400074, China 3. Chiba University, Chiba 263-8522, Japan | 2006 | Science China Earth Sciences2006，49，12： | 34 |
| 2 | Alkaline polymer electrolyte fuel cells: Principle, challenges, and recent progress显示文摘Polymer electrolyte membrane fuel cells (PEMFC) have been recognized as a significant power source in future energy systems based on hydrogen. The current PEMFC technology features the employment of acidic polymer electrolytes which, albeit superior to electrolyte solutions, have intrinsically limited the catalysts to noble metals, fundamentally preventing PEMFC from widespread deployment. An effective solution to this problem is to develop fuel cells based on alkaline polymer electrolytes (APEFC), which not only enable the use of non-precious metal catalysts but also avoid the carbonate-precipitate issue which has been troubling the conventional alkaline fuel cells (AFC). This feature article introduces the principle of APEFC, the challenges, and our research progress, and focuses on strategies for developing key materials, including high-performance alkaline polyelectrolytes and stable non-precious metal catalysts. For alkaline polymer electrolytes, high ionic conductivity and satisfactory mechanical property are difficult to be balanced, therefore polymer cross-linking is an ultimate strategy. For non-precious metal catalysts, it is urgent to improve the catalytic activity and stability. New materials, such as transition-metal complexes, nitrogen-doped carbon nanotubes, and metal carbides, would become applicable in APEFC. | TANG DaoPing, PAN Jing, LU ShanFu, ZHUANG Lin* & LU JunTao Hubei Key Lab of Electrochemical Power Sources College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China | 2010 | Science China Chemistry2010，53，2： | 9 |
| 3 | Analysis of tandem repeats in the genome of Chinese shrimp Fenneropenaeus chinensis显示文摘Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of Chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2159 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 20.6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2% of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42%. In decreasing order, the 20 most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (274), AAT (92), A (56), AAG (28), ATC (27), ATAG (27), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them. | KONG Jie1 & GAO Huan2,3 1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, Chinese Academy of Fishery Sciences, Qingdao 266071, China 2. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China 3. The Graduate School of the Chinese Academy of Sciences, Beijing 100039, China | 2005 | Chinese Science Bulletin2005，50，14： | 7 |
| 4 | COMPLEX HEAT TRANSFER ENHANCEMENT BY FLUID INDUCED VIBRATION显示文摘A new method of heat transfer enhancement by fluid induced vibration was put forward, and its theoretical analysis and experimental study were performed. Though people always try to prophylaxis fluid induced vibration for regarding it as an accident, the utilization space of fluid induced vibration is still very large. The in surface and out surface vibrations which come from the fluid induce elastic tube bundles, can effectively increase the convective heat transfer coefficient, and also decrease the fouling resistance, then increase the heat transfer coefficient remarkably. | Cheng Lin, Qiu YanSchool of Energy Source and Power Engineering, Shandong University, Jinan 250061, China | 2003 | Journal of Hydrodynamics2003，15，1： | 7 |
| 5 | Effect of Fe(III) impurity on the electrochemical performance of LiFePO_4 prepared by hydrothermal process显示文摘Lithium iron phosphate (LiFePO4) was synthesized from LiOH, FeSO4 and H3PO4 by a hydrothermal process at 180℃. The samples were characterized by X-ray diffraction, scanning electron microscopy and chemical analysis. Electrochemical performance of the samples was tested in terms of charge-discharge capacity and cycling behavior. The results indicated that Fe(III) impurity had obvi- ously effect on the electrochemical properties of LiFePO4, and the formation of Fe3+ was caused by the oxidation of Fe2+ in the dissolving and feeding processes accompanying the increase of pH value. It was found that the precipitation separation was effective in decreasing the content of Fe3+ in the solu- tion of FeSO4 and the sealed feeding was useful in preventing the conversion of Fe2+ to Fe3+. When the content of Fe3+ < 0.5 wt%, the hydrothermally synthesized LiFePO4 calcined at 750℃ with sucrose as carbon source exhibited an initial discharge capacity of 154.9 mAh·g-1 at the rate of 0.1 C (1 C = 150 mA·g-1) and the cycling retention rate could reach 98% after 50 cycles at room temperature. | OU XiuQin, XU ShengZhao, LIANG GuangChuan, WANG Li & ZHAO Xia Institute of Power Source & Ecomaterials Science, Hebei University of Technology, Tianjin 300130, China | 2009 | Science China(Technological Sciences)2009，52，1： | 6 |
| 6 | Visualization and quantification of water movement in porous cement-based materials by real time thermal neutron radiography:Theoretical analysis and experimental study显示文摘Water movement in porous cement-based materials is of great importance when studying their deterioration processes and durability.Many traditional methods based on mass changes,electricity or nuclear magnetic resonances are available for studying water transport in cement-based materials.In this research,an advanced technique i.e.thermal neutron radiography was utilized to achieve visualization and quantification of time dependent water movement including water penetration and moisture vapor in porous cement-based materials through theoretical analysis and experimental study.Because thermal neutrons ex-perience a strong attenuation by hydrogen,neutron radiography exhibits high sensitivity to small amounts of water.A neutron transmission analysis for quantitative evaluation of raw radiographic measurements was developed and optimized based on point scattered functions(PScF).The determinations of the real time and space dependent water penetration into uncracked and cracked mortar samples,as well as the drying process have been presented in this paper.It is illustrated that thermal neutron radiography can be a useful research tool for visualization and quantification of water movement in porous building materials.The obtained results will help us to better understand deteriorating processes of cement-based materials and to find ways to improve their durability. | ZHANG Peng1,WITTMANN F H1,2,ZHAO TieJun1,LEHMANN E3 & JIN ZuQuan1 1 Center for Durability & Sustainability Studies of Shandong Province,Qingdao Technological University,Qingdao 266033,China 2 Aedificat Institute Freiburg,Freiburg D-79100,Germany 3 Department of Spallation Neutron Source(ASQ),Paul Scherrer Institute,Villigen PSI CH-5232,Switzerland | 2010 | Science China(Technological Sciences)2010，53，5： | 6 |
| 7 | 太阳能光电、光热技术在住宅建设中的应用显示文摘 | Xinjiang New Energy Sources Stock Co.,Ltd. | 2004 | 住宅科技2004，24，10： | 4 |
| 8 | Geochemical characteristics of pyrolysis gas from epimetamorphic rocks in the northern basement of Songliao Basin,Northeast China显示文摘The Xushen gas field,located in the north of Songliao Basin,is a potential giant gas area for China in the future.Its proved reserves have exceeded 1000×10 8 m 3 by the end of 2005.But,the origin of natural gases from the deep strata is still in debating.Epimetamorphic rocks as a potential gas source are widely spreading in the northern basement of Songliao Basin.According to pyrolysis experiments for these rocks in the semi-confined system,gas production and geochemistry of alkane gases are discussed in this paper.The Carboniferous-Permian epimetamorphic rocks were heated from 300℃to 550℃,with temperature interval of 50℃.The gas production was quantified and measured for chemical and carbon isotopic compositions.Results show thatδ13C 1 is less than?20‰,carbon isotope trend of alkane gas isδ13C 1 <δ13C 2 <δ13C 3 orδ13C 1 <δ13C 2 >δ13C 3 ,these features suggest that the gas would be coal-type gas at high-over maturity,not be inorganic gas with reversal trend of gaseous alkanes (δ13C 1 >δ13C 2 >δ13C 3 ).These characteristics of carbon isotopes are similar with the natural gas from the basin basement,but disagree with gas from the Xingcheng reservoir.Thus,the mixing gases from the pyrolysis gas with coal-typed gases at high-over maturity or oil-typed gases do not cause the reversal trend of carbon isotopes.The gas generation intensity for epimetamorphic rocks is 3.0×10 8 ―23.8×10 8 m 3 /km 2 ,corresponding to Ro from 2.0%to 3.5%for organic matter. | YANG Chun 1 ,LUO Xia 2 ,LI Jian 2 ,LI ZhiSheng 2 ,LIU QuanYou 3 &Wang YuLin 4 1 Department of Earth Sciences,Zhejiang University,Hangzhou 310027,China 2 Research Institute of Petroleum Exploration and Development(Langfang Branch),Langfang 065007,China 3 Research Institute of Petroleum Exploration and Development,Beijing 100083,China 4 Department of Source and Environment,Liaoning Technical University,Fuxin 123000,China | 2008 | Science China Earth Sciences2008，51，S1： | 3 |
| 9 | Response characteristics of an ascending auditory neuron AN3 and its projections in the brain of the bushcricket Gampsocleis grationsa显示文摘The phonotaxis of bushcrickets demonstrates that they have goodcapability of recognizing conspecific songs and locating the sound source,which bases on complicated auditory mechanisms of the central nervoussystem(CNS).This article describes the response characteristics of AN3,an auditory ascending neuron in the prothoracic ganglion,and its projec-tions within the brain.The AN3,with a quasi-tonic discharge pattern,has high sensitivity,directionality and ability to encode sound intensity.Therefore,it plays an important role in auditory information processingof CNS.Its projections in the brain are mainly concentrated in the lateralzone of the deutencephalon,where synaptically connecting local auditoryinterneurons in the brain. | GAO Panpan and SHEN Jun -Xian(Institute of Biophysics, Academia Sinica, Beijing 100080)The phonotaxis of bushcrickets demonstrates that they have good capability of recognizing conspecific songs and locating the sound source, which bases on complicated auditory mechanisms of the central nervous system (CNS). This article describes the response characteristics of AN3, an auditory ascending neuron in the prothoracic ganglion, and its projections within the brain. The AN3 , with a quasi-tonic discharge pattern, has high sensitivity, directionality and ability to encode sound intensity. Therefore, it plays an important role in auditory information processing of CNS. Its projections in the brain are mainly concentrated in the lateral zone of the deutencephalon, where synaptically connecting local auditory interneurons in the brain. | 1992 | Chinese Journal of Acoustics1992，11，1： | 3 |
| 10 | 采购绩效评价与评价内容分析显示文摘在一个高度全球化和高度竞争的环境下,想要保持企业的高效率运作,保证企业的持续经营,对企业运行的各个方面进行评价是不可或缺的。采购绩效评估,主要是评价采购部门、采购管理人员和专业经理,并衡量目前采购环节的营运效率和采购供应功能的极小差异,以及预算或预测绩效的差异。适当的绩效评估的建立,可以帮助企业管理和公司资源集中在关键领域,它是加强沟通与经营管理的基础。 | Sources Messenger | 2008 | 国际市场2008，，5： | 2 |
| 11 | Experimental study on high-voltage solar array sustained arc discharge induced by high charging显示文摘It has been reported that sustained arc discharge induced by electrostatic discharge (ESD) could cause permanent damage to high-power and high-voltage solar array of spacecrafts. The paper focuses on ESD simulating experiments on Si and GaAs samples, and induces sustained arc discharge. The physical mechanism of sustained arc discharge is discussed by comparing the charging/discharging phenomena between Si and GaAs samples. The experiments show that sustained arc discharge can produce a permanent short-circuit channel between solar cell strings through which the solar array’s photovoltaic power may flow out sustainedly. The analyses show that sustained arc discharge strongly depends on solar array structure, solar array operating voltage, ESD characteristics and cell materials. | LI Kai1,2, XIE ErQing1, WANG Li2, LIU YanXia1, YANG Yang1, SUN YanZheng3, CUI XinYu3 & MAI ShengLi2 1 School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China 2 Lanzhou Institute of Physics, Lanzhou 730000, China 3 Tianjin Institute of Power Source, Tianjin 300381, China | 2007 | Science China(Technological Sciences)2007，50，2： | 2 |
| 12 | Efficiency of sediment transport by flood and its control in the Lower Yellow River显示文摘This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for Sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 20 kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 20 kg/m3, the optimized controlling discharge ranges from 2390 to 2900 m3/s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir. | NI Jinren1, LIU Xiaoyong2, LI Tianhong1, ZHAO Ye’an3 & JIN Ling1 1. Department of Environmental Engineering, Peking University The Key Laboratory of Water and Sedi- ment Sciences, Ministry of Education, Beijing 100871, China 2. General Institute of Water Resources and Hydropower Planning and Design, Ministry of Water Re- sources, Beijing 100011, China 3. The Yellow River Conservancy Commission, Zhengzhou 450003, China | 2004 | Science China(Technological Sciences)2004，47，z1： | 2 |
| 13 | Procedures, and Microeconomic Effects of Inno- vation 显示文摘 | Dosi G Sources | 1988 | Journal of Economic Literature1988，26，3： | 1 |
| 14 | Vitamin B biosynthesis in higher plants 显示文摘 | B6 status Nutricion sources in American Tambasco-Studart M Titiz O Raschle T | 2005 | Proceedings of the National Academy of Sciences of the United States of America2005，102，13： | 1 |
| 15 | A survey of automated assessment ap- proaches for programming assignments 显示文摘 | Ala-Mutka Kirsti Source | 2005 | Computer Science Education Volume 15 Number 22005，2005，： | 1 |
| 16 | 5 in Beijing: seasonal perspective 显示文摘 | ZHANG R JING J TAO J Chemical characterization and source apporlionment of PM2 | 2013 | Atmospheric Chemistry and Physics2013，13，14： | 1 |
| 17 | Industrial derivatives,and commercial applications of cellulose显示文摘 | | 1995 | Carbohydr Eur1995，12，： | 1 |
| 18 | Precedures and Microeconomic Effects of In- novation显示文摘 | Dosi G Sources | 1988 | Journal ''Economic Literature1988，26，3： | 1 |
| 19 | Validating the approach for phosphorus and sediment losses in grazed headwater catchments显示文摘 | McDowell R W Srinivasan M So Identifying critical source areas for water quality: 2 | 2009 | Journal of Hydrology2009，379，12： | 1 |
| 20 | Dynamic behaviors of the bridge considering pounding andfriction effects under seismic excitations 显示文摘 | KIM Sang-hyo LEE Sang-woo MHA Ho-seong Source | 2001 | StructuralEngineering and Mechanics2001，10，6： | 1 |
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