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On the variation of water resource structure in the Lower Yellow River

Science China(Technological Sciences) 2004年第z1期47卷 127-141页

作者： NI Jinren1. WANG Yudong1. QIAN Zhenghan1. LI Tianhong1.& ZHAO Yean2 1. Department of Environmental Engineering, Peking University The key Laboratory of Water and Sedi- ment Sciences, Ministry of Education, Beijing 1.0871. China 2. Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou 450003, China 1. Department of Environmental Engineering Peking University 100871 Beijing China2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China3. Institute of Hydraulic Research YellowRiver Conservancy Commission 450003 Zhengzhou China

In view of river functions and the Minimum Water Demand for River Ecosystem (MWDRE), the water resources in the Lower Yellow River is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1.50 to 2001.is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1.50s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1.90s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the Yellow River, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.

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Morphologies of Fe-66.7 at.%Si alloy solidified in a drop tube

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Science China(Physics,Mechanics & Astronomy) 2005年第6期48卷 658-666页

作者： WANG Haiyan1.2, LIU Riping1. MA Mingzhen1. JING Qin1. LI Gong1. SUN Liling2 & WANG Wenkui1.2 1. key Laboratory of Metastable Materials Science & Technology, Yanshan University, Qinhuangdao 066004, China 2. Institute of Physics, Chinese Academy of Sciences, Beijing 1.0080, China 1. key Laboratory of Metastable Materials Science & Technology Yanshan University 066004 Qinhuangdao China 2. Institute of Physics Chinese Academy of Sciences 100080 Beijing China

Solidification of 0.1.1.0 mm diameter droplets of Fe-66.7 at.%Si alloy was achieved in a 3 m drop tube. The XRD, EDS, and SEM measurements reveal that all the droplets are composed of the primary phase α and the α+ε eutectic. With decreasing droplet diameter, the growth mode of the primary phase α changes from faceted to nonfaceted growth and the eutectic changes from needle-like to anomalous eutectic. In addition, the width of the primary phase α decreases with decreasing droplet size. The different cooling rates and undercooling levels corresponding to the samples with different sizes are responsible for the morphology changes. The cooling rates of the samples with different diameters during free fall were calculated and their effects on the microstructure formation were discussed. This kind of transition is also found inside the same sample, which is due to the larger cooling rate on the surface than at the center.

关键词： Fe-Si alloy, solidification, drop tube, undercooling.

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Structures and stability of isomers of[Si,N,N,P]system

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Science China Chemistry 2004年第2期47卷 98-105页

作者： KAN Wei1. YU Haitao1. LI Mingxia1. FU Honggang1.2 & SUN Jiazhong1.2 1. College of Chemistry and Chemical Engineering, Heilongjiang University, Harbin 1.0080, China 2. State key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 1.0023, China 1. College of Chemistry and Chemical Engineering Heilongjiang University 150080 Harbin China 2. State key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University 130023 Changchun China

Some stationary points on the potential energy surface of [Si, N, N, P] system were located at the B3LYP/6-31.G(d) and QCISD(t)/6-31.+G(2df)(single-point) levels of theory, while the isomerization, structures, and stability of these obtained isomers were suggested. The computed results indicate that only four-membered ring isomer SiNPN(E1. 2A'), which possesses butterfly-like structure and Si-P cross bonding, is kinetically stable in all optimized isomers. Other isomers may be considered as kinetically unstable towards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, the present paper also proposes electronic and geometric structures, vibrational frequencies and the corresponding vibrational modes, dipole moments, and rotational constants of isomer E1. To make use of the computed results, we can clearly know that the reaction pathway via an intermediate E3 (SiNPN) is the most favorable channel producing isomer E1.from fragments SiN(2Π) and PN (1.), which have been well characterized in space, and thus, isomer E1.can be considered as a candidate for interstellar observation. The reaction enthalpy of SiN(2Π) + PN(1.)→ E1.and the standard enthalpy of formation of isomer E1.are 21..25 and 457.99 kJ/mol, respectively, at 298.1. K. keywords potential energy surface - [Si,N,N,P] system - isomerization - kinetic stability

关键词： potential energy surface, [Si,N,N,P] system, isomerization, kinetic stability.

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Study on the electric double layer of a cylindrical reverse micelle with functional theoretical approach

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Science China Chemistry 2006年第3期49卷 219-224页

作者： WANG Zhengwu1.2, GUO Baomin2, ZHANG Gexin1.& YU Huixin1.1. key Laboratory of Industrial Biotechnology of Ministry of Education, Southern Yangtze University, Wuxi 21.036, China 2. School of Chemical and Material Engineering, Southern Yangtze University, Wuxi 21.036, China 1. key Laboratory of Industrial Biotechnology of Ministry of Education Southern Yangtze University Wuxi 214036 China 2. School of Chemical and Material Engineering Southern Yangtze University Wuxi 214036 China

The iterative method in functional analysis is applied to looking for asolution of the Poisson-Boltzmann equation in order to describe the problems of the distribution ofthe potentials in the electric double layer (EDL) inside the water pool for a cylindrical inversemicelle. Potentials as a function of the position of a particular point in EDL are computed, whichdisplay a quantitative agreement with those from earlier calculation of Debye and Huckel in the caseof low potentials. But it is also shown that in the higher-potential range the iterativecalculations can give more accurate results. These results indicate the utility of this functionalanalysis technique in the description of the properties of EDL for a cylindrical inverse micelle.

关键词： cylindrical reverse micelle, electrostatic double layer, Poisson-Boltzmann equation, functional analytic theory.

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A restudy of Oryctocephalus indicus (Reed,1.1.)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1.*, YUAN Jinliang~2, PENG Shanchi~ 2,3 , YANG Xinglian~1. PENG Jin~1. LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, Guiyang 550003, China 2. Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 21.008, China 3. State key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 21.008, China 4. Department of Geological Science, Ohio State University, Columbus, OH 4321., USA 5. Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China) College of Resource and Environment of Guizhou University Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1.1.), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1.1.), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 1.34, are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003 is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 1. segments, and a small pygidium that bears 2—3 axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3 and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1.62 or Arthricocephalus chauveaui Bergeron, 1.99.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

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Carbon and Oxygen Stable Isotope Values and Microfossils at 41.4-4.5ka BP in Tai Co,Tibet,China,and Their Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1036-1050+1052-1056+1051页

作者： ZHENG Mianping~(1.2,*),LIU Junying~(1.3),MA Zhibang~(1.4),WANG Hailei~(1.2) and MA Nina~(1.2) 1.MLR key Laboratory of Saline Lake Resources and Environment,Institute of Mineral Resources,CAGS, Beijing 1.0037,China 2 Research and Development Center for Saline Lakes and Epithermal Deposits,Chinese Academy of Geological Sciences,Beijing 1.0037,China 3 Institute of Geology,Chinese Academy of Geological Sciences,Beijing 1.0037,China 4 key Laboratory of Cenozoic Geology and Environment,Chinese Academy of Sciences,Beijing 1.0029, China MLR key Laboratory of Saline Lake Resources and Environment Institute of Mineral Resources CAGS Beijing 100037 China Research and Development Center for Saline Lakes and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China key Laboratory of Cenozoic Geology and Environment Chinese Academy of Sciences Beijing 100029 China *Correspondence: Mianping ZHENG *Correspondence: Corresponding author. E-mail: zhengmp2010@***

Two sedimentary sections were measured at Tai Co(Co means lake in Tibetan) in western Tibet,*** two sections are almost all composed of clay carbonate beds except in their lower parts where there are carbonized plants at>1. cm depths and dark-colored carbonate clay and clay at 50-70 cm depths,yielding abundant gastropods,ostracods,and *** carbon and oxygen stable isotope values of carbonate,ostracods,and charophytes and ecological features of microfossil communities indicate the following climatic change in the area from 41.4 to 4.5 ka BP:at 41.4-26.2 ka BP,the climate was relatively wet;at 26.2-25.5 ka BP,it was slightly warm-dry;at 25.5-22.5 ka BP,it was warm-wet;at 22.5-21.0 ka BP,it was slightly cold-wet;at 20.5-1..5 ka BP,it became cold abruptly and slightly wet,implying the climate of the last glacial maximum;at 1..5-1..0 ka BP,it was slightly cold-dry;at 1..0-1..8 ka BP,it was slightly warm-wet;at 1..8-1..4 ka BP,it was relatively cold-dry, roughly equivalent to the climate of the Younger Dryas,and at 1..4 ka BP,the temperatures began to rise again;at 1..4-9.4 ka BP,it was slightly warm-wet;at 9.4-8.5 ka BP,there occurred short warm-wet oscillations;at 8.5-7.9 ka BP,it was slightly dry-cold,representing a strong temperature-lowering and drying event in the postglacial stage;at 7.8-6.3 ka BP,it was slightly warm-wet;at 6.3-4.5 ka BP,the climate tended to be cold-dry.4.5 ka BP recorded the maximum aridity since the late part of the late Pleistocene.

关键词： sedimentary environment index paleoclimatic changes late Pleistocene-Holocene(41.4-4.5 ka BP) Tai Co Tibet

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Joint exploration of crustal structure in Fuzhou basin and its vicinities by deep seismic reflection and high-resolution refraction as well as wide-angle reflection/refraction

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Science China Earth Sciences 2005年第7期48卷 925-938页

作者： ZHU Jinfang1. XU Xiwei2, ZHANG Xiankang3, HUANG Zonglin1. CHEN Xiangxiong1. FANG Shengming3, LIU Baojin3, ZHENG Rongzhang2,4 1. Seismological Bureau of Fujian Province,Fuzhou 350003,China 2. Institute of Geology,China Earthquake Administration,Beijing 1.0029,China 3. Research Center for Exploration Geophysics,China Earthquake Administration,Zhengzhou 450002,China 4. State key Laboratory of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 1.0029,China Seismological Bureau of Fujian Province Fuzhou 350003 China Institute of Geology China Earthquake Administration Beijing 100029 China Research Center for Exploration Geophysics China Earthquake Administration Zhengzhou 450002 China State key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China

The Fuzhou basin and its vicinities are located at the northern end of the southeastern coastal seismic zone of the mainland of China. By the joint explorations of high-resolution seismic refraction and wide-angle reflection/refraction as well as deep seismic reflection in the region, which is the first synthetic profile in China, its fine velocity structure and geometric structure from the ground to Moho discontinuity is obtained. The result shows that the crust is obviously layered with a thickness of about 32 km. Basically, it consists of two parts: upper crust and lower crust. The velocity of the upper crust is 5.9-6.2 km/s in which there is a 3-4-km-thick weak low-velocity layer between the depths of 1.-1. km, while the velocity of the lower crust in the range of 6.3-7.2 km/s. There exists a strong velocity gradient layer about 3 km thick above the Moho discontinuity whose velocity increases from 6.5 to 7.27 km/s. There exist high-angle normal faults that are small in size and extend only in the shallow crust. These faults are the secondary developed on the hanging wall of westward dipping low-angle normal faults. Thus, their seismogenic ability is limited, however, there exists a high-angle deep fault in the crust from Changle-Zaoan fault zone to seashore fault zone. This deep fault has cut the interface between the upper and lower crusts and Moho discontinuity, and may be the deep structure to trigger destructive earthquake source in future to affect Fuzhou City. These results have advanced the detecting precision of the deep structure in the southeastern coastal seismic zone of the mainland of China. In the aspect of the combined feature of the deep and shallow extensional structures that consist of the westward dipping low-angle normal faults and secondary normal faults on their hanging walls in the upper crust, it is firstly obtained that a united structural interpretation has deepened the knowledge about the deep dynamic process in the southeastern coasta

关键词： deep seismic reflection high-resolution seismic refraction wide-angle.

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An improved method for phasing crystal structures with low non-crystallographic symmetry using cryo-electron microscopy data

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Protein & Cell 2015年第12期6卷 919-923页

作者： Jia Wang (1. (2) (3) Weiguang Wang (1. (2) Wen Song (2) (3) (4) Zhifu Han (2) (3) (4) Heqiao Zhang (2) (3) (4) Jijie Chai (2) (3) (4) Hongwei Wang (2) (3) (4) Jiawei Wang (1. (2) 1.State key Laboratory of Membrane Biology School of Life Sciences Tsinghua University Beijing 100084 China 2.Center for Structural Biology School of Life Sciences Tsinghua University Beijing 100084 China 3.Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University Beijing 100084 China 4.Ministry of Education Key Laboratory of Protein Science School of Life Sciences Tsinghua University Beijing 100084 China

Cryo-electron microscopy （cryo-EM） and macromolecular crystallography （MX） both allow the creation of three-dimensional images of biological macromolecules. EM data usually provide access to three-dimensional reconstructions of large biological complexes at low resolution, whereas MX usually delivers atomic or quasi-atomic resolution structures （1.3 A）.

关键词： Phase Error Molecular Replacement Histogram Match TLR1. Molecule Solvent Flatten

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Effect of TMCP Parameters on the Microstructure and Properties of Q460qNH Steel

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 917-921页

作者：王磊高彩茹 State key Laboratory of Rolling and Automation Northeastern University

The effects of TMCP parameters, consisting of finish cooling temperature and start rolling temperature in non-recrystallization region, on the final microstructure and mechanical properties of Q460 qNH steel were studied by tensile, Charpy impact tests and optical microscopy. The TMCP parameters for Q460 qNH steel were optimized by laboratory experiments. The results show that the yield strength and tensile strength increase with the finish cooling temperature, and the microstructure of Q460 qNH steel consists of ferrite and granular bainite.

关键词： TMCP mechanical properties M/A constituent Q460 qNH steel

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Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

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Science in China(Series F) 2009年第12期52卷 2415-2423页

作者： XU ChangLong1.3,4, YANG Wei1.2 & YE WeiChen4 1.State key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications, Beijing 1.0044, China 2 State key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University, Beijing 1.0044, China 3 National Mobile Communications Research Laboratory, Southeast University, Nanjing 21.096, China 4 Intel Corporation, Beijing Kerry Center, Guanghua Road 1. Beijing 1.0020, China State key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100044 China State key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China Intel Corporation Beijing Kerry Center Guanghua Road 1 Beijing 100020 China

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

关键词： block code product code iterative decoding

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