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Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

Chinese Science Bulletin 2003年第B6期48卷 42-48页

作者： FU Mingzuo~(1,2.3), li Zhen~1, XU Xiaowei~1 & SHl Xuefa~1 1. Key Laboratory of Marine Sedimentology and Environmental geology, First {2. of Oceanography. State Oceanic administration, Qingdao 2.6061. china 2. {2. of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071. china 3. Graduate School, Chinese Academy of Sciences, Beijing 100039. china Key Laboratory of Marine Sedimentology and Environmental geology First institute of Oceanography State Oceanic Administration Qingdao China institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School Chinese Academy of Sciences Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2. eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3) the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14年代测定底基压型数据更新世沉积环境大西洋

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Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： li Chensha1*, WANG Dazhi1, zhang Baoyou2. WANG Xiaofeng1, CAO Maosheng3 and liANG Ji1(1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, china 2. Center for Analysis and Measurement, Harbin institute of Technology, Harbin 150001, china 3. School of Material Science and Engineering, Tsinghua University, Beijing 100084, china) Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China Ctr. for Analysis and Meas. Harbin Inst. of Technol. Harbin 150001 China Sch. of Mat. Sci. and Eng. Tsinghua Univ. Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

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Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2.*) zhang Hongfu~2.liu Xiaoming~3 li Zhitong~4 (1.School of Earth and Space Sciences,Peking University,Beijing 100871,china 2.institute of geology and Geophysics and Key Laboratory of Mineral Resources,Chinese Academy of Sciences,Beijing 10002.,china 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.institute of geology and Mineral Resources of Shenyang,Shenyang 110032.china) School of Earth and Space Sciences Peking University Beijing 100871 China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Acad. of Sci. Beijing 100029 China Key Laboratory of Continental Dynamics Northwestern University Xi'an 710069 China institute of geology and Mineral Resources of Shenyang Shenyang 110032 China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

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High-safety and high-voltage lithium metal batteries enabled by nonflammable diluted highly concentrated electrolyte

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Nano Research 2024年第4期17卷 2638-2645页

作者： Han zhang Ziqi zeng Shuping Wang Yuanke Wu Changhao {2. Mengchuang {2.u Xinlan Wang Shijie Cheng Jia Xie State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Grid Anhui Electric Power Research institute Anhui Province Key Laboratory of Electric Fire and Safety Protection(State Grid Laboratory of Fire Protection for Transmission and Distribution Facilities)Hefei 230601China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China

lithium metal batteries(LMBs)show great promise for achieving energy densities over 400 Wh·kg^(-1).However,highly flammable organic electrolytes are a long-lasting problem that triggers safety hazards and hinders the commercial application of ***,a nonflammable diluted highly concentrated electrolyte(DHCE)with ethoxy(pentafluoro)cyclotriphosphazene(PFPN)as a diluent is developed to simultaneously achieve high safety and cycling stability of high-voltage *** optimal DHCE not only ensures reversible li deposition/dissolution behavior with a superior average Coulombic efficiency(CE)over 99.1%on lithium metal anode(LMA),but also suppresses side reactions and stress crack on the liCoO_(2.(LCO)under high cut-off *** newly developed DHCE exhibits high thermal stability,showing complete nonflammability and reduced heat generation between the electrolyte and delithiated LCO/cycled *** work offers an opportunity for rational designing nonflammable electrolytes toward high-voltage and safe LMBs.

关键词： lithium metal batteries thermal stability nonflammable electrolyte high-voltage phosphazene

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A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW china

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Science china Earth Sciences 2006年第2期49卷 154-162页

作者： li Chunhai12. TANG lingyu1, FENG Zhaodong3,4, {2. Hucai2. WANG Weiguo3 & AN Chenbang3 1. Nanjing institute of geology and Palaeontology, Chinese Academy of Sciences, Nanjing 2.0008, china 2. Nanjng institute of Geography and limnology, Chinese Academy of Sciences, Nanjing 2.0008, china 3. Environment and Resources College, Lanzhou University, Lanzhou 730000, china 4. Beijing Normal University, Beijing 100875, china Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China Nanjng institute of Geography and limnology Chinese Academy of Sciences Nanjing China Environment and Resources College Lanzhou University Lanzhou China Beijing Normal University Beijing China

With the support of 18 AMS-14C data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 44.2.to 11 ka B.P. in the Jingning area. Over the period of 44―2. ka B.P. (MIS3), coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 2. ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3, further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

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An experimental indoor phasing system based on active optics using dispersed Hartmann sensing technology in the visible waveband

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Research in Astronomy and Astrophysics 2011年第9期11卷 1111-1122页

作者： Yong zhang Gen-Rong liu Yue-Fei Wang Ye-Ping li Ya-Jun zhang liang zhang Yi-Zhong zeng Jie zhang National Astronomical Observatories / Nanjing institute of Astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China Key Laboratory of Astronomical Optics ＆ Technology Nanjing Institute of Astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technicians. Instead of using a monolithic primary mirror, more and more large telescopes, which are currently being planned or in construction, have adopted a segmented primary mirror design. Therefore, how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infrared telescopes. The Dispersed Fringe Sensor （DFS）, or Dispersed Hartmann Sensor （DHS）, is a non-contact method using broadband point light sources and it can estimate the piston by the two-directional spectrum formed by the transmissive grating＇s dispersion and lenslet array. Thus it can implement the combination of co-focusing by Shack-Hartmann technology and phasing by dispersed fringe sensing technologies such as the template-mapping method and the Hartmann method. We introduce the successful design, construction and alignment of our dis- persed Hartmann sensor together with its design principles and simulations. We also conduct many successful real phasing tests and phasing corrections in the visible waveband using our existing indoor segmented mirror optics platform. Finally, some conclusions are reached based on the test and correction of experimental results.

关键词： astronomical instrumentation -- methods and techniques -- instrumen- tation: active optics -- adaptive optics

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Fundamental study of CO_2.control technologies and policies in china

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Science china(Technological Sciences) 2008年第7期51卷 857-870页

作者： JIN HongGuang1, zhang Xiliang2. GAO lin1, YUE li2. HE JianKun2.& CAI RuiXian1 1 institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, china 2.institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China institute of Nuclear and New Energy Technology Tsinghua University Beijing China

The technical roadmap and policies for CO2.mitigation suitable for china are a common center of attention in the fields of energy, environment, and management science in the country. Emphasizing interaction between technical research and policy research, this work discovers the potential breakthrough in the integrated field. The technical difficulties of recovering CO2.are pointed out, the mechanism of combining CO2.recovery with energy conversion is investigated, and the basic principle for integrating an environmental-friendly energy system is discussed. Moreover, the formulation of a new energy system that can recover CO2.with very low or even zero energy penalty is proposed, while the assessment methodology and model system for the technical roadmap of CO2.emission control are developed. Finally, a new technical roadmap constructing an energy network suitable for china is proposed, which may provide a new way for the development of sustainable energy and environment technologies.

关键词： CO2 capture and storage technical roadmap energy policy

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A statistical analysis of typhoon frequency and application in design wave height

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Acta Oceanologica Sinica 2011年第4期30卷 24-32页

作者： WANG liping zhang Jianfang li Yongping zhang Yufang College of Mathematical Science Ocean University of China Qingdao 266071 China Shanghai Typhoon institute Shanghai 200030 China

A typhoon leading is an important natural disaster to many disasters to china. A giant wave caused by it has brought large threat for an offshore project. Based on the maximum entropy principle,one new model which has 4 undetermined parameters is constructed,which is called the discrete maximum entropy probabilistic model. In practical applications,the design wave height is considered as soon as possible in a typhoon affected sea areas,the result fits the observed data well. Further more this model does not have the priority compared with other distributions as Poisson distribution. The model provides a theoretical basis for the engineering design more reasonable when considering typhoon factors comprehensively.

关键词： discrete maximum entropy compound extreme values typhoon wave heights

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Field experimental study on the effect of thawed depth of frozen alpine meadow soil on rill erosion by snowmelt waterflow

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International Soil and Water Conservation Research 2024年第1期12卷 54-63页

作者： Ying Zheng Xiaonan Shi Fan zhang Tingwu Lei Chen zeng Xiong Xiao {2. Wang Guanxing Wang State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100101China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China College of Geographic Science Hunan Normal UniversityChangsha410081China

Soil erosion by snow or ice melt waterflow is an important type of soil erosion in many high-altitude and high-latitude regions and is further aggravated by climate *** snowmelt waterflow erosion process is affected by soil freeze-thaws and is highly dynamically *** this study,a methodology was developed to conduct in situ field experiments to investigate the effects of the thawed depth of the frozen soil profile on snowmelt waterflow *** method was implemented on an alpine meadow soil slope at an altitude of 3700 m on the northeastern Tibetan *** erosion experiments involved five thawed soil depths of 0,10,30(35),50,and 80(100)mm under two snowmelt waterflow rates(3 and 5 L/min).When the topsoil was fully frozen or shallow-thawed(≤10 mm),its hydrothermal and structural properties caused a significant lag in the initiation of runoff and delayed soil erosion in the initial *** runoff and sediment concentration curves for fully frozen and shallow-thawed soil showed two-stage patterns characteristic of a sediment supply limited in the early stage and subject to hydrodynamic-controlled processes in the later ***,this effect did not exist where the thawed soil depth was greater than 30 *** deep-thawed cases(≥30 mm)showed normal hydrograph and sedigraph patterns similar to those of the unfrozen *** findings of this study are important for understanding the erosion rates of partially thawed soil and for improving erosion simulations in cold regions.

关键词： Snowmelt waterflow erosion Hillslope erosion process Soil freeze and thaw Runoff generation In situ experimental method

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Indoor imitation experimental study on driving factors of rainfall-runoff process

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Science china Earth Sciences 2005年第3期48卷 417-428页

作者： zhang Shifeng1, liU Changming 1, XIA Jun1, TAN Ge 1, li lin1, liU Caitang1, ZHOU Changqing 1 & GUO Lei2.1. institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. College of Water Resources and Hydropower Engineering, Wuhan University, Wuhan 430072. china institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China College of Water Resources and Hydropower Engineering Wuhan University Wuhan China

The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The re- search results of 179 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south{2. region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north{2. where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north{2. region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north{2. region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north{2. region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south{2. region and the basic theoreti- cal research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with inten

关键词： rainfall-runoff, driving factors, indoor imitation, experiment.

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