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Coupling interaction between biodiversity and aquatic habitat area in Western Route project vicinity

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Water Science and Engineering 2010年第3期3卷 354-360页

作者： Shi-min TIAN Zhao-yin WANG Xiang-jun LIU Shi-kui LIANG Key Laboratory of Yellow River Sediment MWR Institute of Hydraulic Research YRCC Zhengzhou 450003 P. R. China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 P. R. China Henan Water and Power Consulting Engineering Co. Ltd. Zhengzhou 450008 P. R. China Department of ltyctraulic Engineering North China University of Water Resources and Electric Power Zhengzhou 450008 P. R. China

The Western Route of the South-to-North Water Transfer project will divert water from the upper Yangtze River and its tributaries, the Dadu River and Yalong River, to the upper Yellow River. The project may ease the water shortage in the Yellow River Basin. However, it may also have some effects on the ecosystem in the upper Yangtze River Basin. Benthic invertebrates play an important role in the river ecosystem, particularly in the circulation of materials and nutrition. Benthic invertebrates are widely used to quickly assess river ecosystems because of their rapid response to changes in the water environment. The diversity of benthic invertebrates is closely associated with the aquatic habitat area. This study examined this interaction by sampling the benthic invertebrates in an expanding area. The conclusions are that the diversity of benthic invertebrates begins to decrease when the aquatic habitat area is reduced to 45% of the original area, and decreases dramatically when the aquatic habitat area is reduced to 10% of the original area. The aquatic habitat area should be kept at more than 45% of the original area in order to maintain the significant diversity of benthic invertebrates.

关键词： Western Route project South-to-North Water Transfer project," river ecosystem benthic invertebrates biodiversity aquatic habitat area

Regularities of Formation of Ternary Intermetallic Compounds between One Transition Element and Two Non-transition Elements

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Journal of Materials Science & Technology 2001年第6期17卷 597-600页

作者： Lixiu YAO, Nianyi CHEN and Jie YANG Institute of Image Processing and Pattern Recognition, Shanghai Jiaotong University, Shanghai 200030, China [Manuscript received August 11, 2000, in revised form October 6, 2000] Inst. of Image Proc. Shanghai Jiaotong Univ. Shanghai 200030 China

The pattern recognition methods and a four-parameter model, Eased on extension of Miedema's cellular model of alloy phases, are used to study the regularities of formation of ternary compounds between one transition element (T) and two non-transition elements (N, N') (T-N-N' system). The influences of phi (electronegativity), n(ws)(1/3)(valence electron density in Wagner-Seitz cell), R(Pauling's metallic radii) and Z (number of valence electrons in atom) on the formation of the ternary intermetallic compounds were investigated.

关键词： Figure

Study on the Method for Measuring Nano-Displacement

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Journal of Wuhan University of Technology(Materials Science) 2001年第3期16卷 70-72页

作者：李银祥 Measuring Center Wuhan University of Technology Wuhan 430070 China

A new method for measuring nano-displacement is discussed. Theresolution of shift is as far as 1 nm. The principle of quantumtunneling effects was used to design the instrument. With the tunnelbetween the sample and the needlepoint and under the control ofclosed loop system, the instrument works at constant current mode, sothat the high precision displacement can be got.

关键词： nanometer displacement measurement

126Gln is the residue of human IL-2 binding to IL-2R γ subunit

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Science China(Life Sciences) 1997年第2期40卷 159-168页

作者：王志勇郑仲承孙兰英刘新垣 Shanghai Institute of Biochemistry Chinese Academy of Sciences Shanghai 200031 China

The 126Gln of human interleukin-2 (IL-2) is a conserved amino acid residue. After substitution of 126Gln with Asp, the binding abilities of this mutant to different composites of IL-2 receptor (R) subunits have been determined. Results show that 126Asp-IL-2 has higher affinity to IL-2R α βγ complex and normal affinity to IL-2R α β complex, but loses its binding ability to IL-2R β γ complex, demonstrating that the 126Gln is the residue of human IL-2 which binds to IL-2R 7 subunit.

关键词： IL-2 IL-2R binding siu.

Influence of TiO_2 Mineralizer on the Crystalline Structure of Cordierite Synthesized from Aluminum Slag

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Chinese Journal of Structural Chemistry 2005年第5期24卷 596-600,493页

作者：阮玉忠吴任平于岩 College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

By adding small amount of TiO2, aluminum slag could be used to synthesize cor- dierite. α-Al2O3, TiO2 and dehydrated talc could generate solid solution to accelerate the solid-state reaction to form cordierite. The experimental results show that the content of cordierite increases with the increase of TiO2 added. 3.0% of TiO2 is determined to be the best amount, because all crystalline substances are converted into cordierite at this content. Philips X’pert plus software analysis shows that when the content of TiO2 is from 0 to 1.0%, cordierite has the same hexagonal structure as the single crystal and the lattice parameters change slightly; when the content of TiO2 is from 1.0 to 2.0%, the cordierite still keeps hexagonal structure but the lattice parameters change greatly; when the content of TiO2 is from 2.0 to 3.5%, the cordierite is converted from hexagonal into rhombic and the lattice parameters change accordingly.

关键词： aluminum slag TiO2 mineralizer cordierite crystalline structure

Cloning of a novel cDNA regulated by all-trans retinoic acid in human lung adenocarcinoma

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Progress in Natural Science:Materials International 1999年第10期9卷 3-5页

作者：刘桂中,刘芝华,Giovanni LEVI,吴旻 State Key Laboratory of Molecular Oncology Cancer Institute Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100021 China State Key Laboratory of Molecular Oncology Cancer Institute Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100021 China Laboratory of Molecular Biology National Institute for Cancer Research Genova Italy State Key Laboratory of Molecular Oncology Cancer Institute Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100021 China

To characterize genes associated with differentiation/apoptosis induced by all- trans retinoic acid (ATRA) in human lung cancer cells, the mRNA differential display was employed and a cDNA fragment RAa7 was obtained which is up-regulated by ATRA. Search for homologous sequences in GenBank databases demonstrates that RAa7 is a novel sequence which has never been reported. Here evidence is provided that the RAa7 gene may be a tissue-specific expressing gene and has a major transcript of 1.4 kb. RAa7 gene is down-regulated during differentiation or apoptosis in several other kinds of lung cancer cells induced by ATRA and N- (4-hydroxyphenyl) retinamide (4HPR) . This suggests that either the up- or down-regulation of RAa7 gene may be involved in the processes of cell differentiation or apoptosis.

关键词： mRNA differential display retinoic acids cell differentiation apoptosis cancer

Studies on the Structure and Properties of Multiphase Al_2O_3 Abrasion-resistant Ceramics

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Chinese Journal of Structural Chemistry 2006年第7期25卷 805-810页

作者： WU Ren-Ping YU Yan RUAN Yu-Zhong College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

The Al2O3 abrasion-resistant ceramics is successfully prepared by using waste aluminum sludge as the main raw material with the addition of a little clay, talc and barium carbonate. The crystal structure and microstructure of ceramic are characterized by means of XRD, SEM, etc., and the physical and mechanical properties are also tested. The results show that besides the phase of corundum, a little mullite, Mg-Al spinel and hyalophane phases also exist in the product. These phases are produced via reaction in-situ, which can inhibit the overgrowth of Al2O3 grain in grain boundary, and improve the integral property of the material.

关键词： Al2O3 ceramic crystal structure property in-situ synthesis

Effect of Cerium on Microstructures and High Temperature Oxidation Resistance of An Nb-Si System In-Situ Composite

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Journal of Rare Earths 2007年第4期25卷 474-479页

作者：刘爱勤孙璐李树索韩雅芳 School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics

Nb-16Si-24Ti-6Cr-6A1-2Hf-xCe （x =0, 0.05, 0.1,02.5, 0.5, 1 （%, atom fraction）） in situ composites were prepared by arc melting The microstmcture and the effect of rare earth element cerium on 1250℃ oxidation resistance of the composites were investigated with scanning electron microscopy （SEM） and X-ray energy disperse spectrum （EDS）, as well as X-ray diffraction （XRD）. The experimental results showed that the high temperature oxidation resistance of the alloy was improved by adding a proper amount of cerium （Ce）. The effect of Ce was considered as the concurrent of the following three factors： first, the oxide of Ce formed in the interface reduced the internal oxidation rate; second, the lath shaped oxide containing Ce increased the cracking resistance and reduced the expansion of the oxide scale; and third, the decrease of the sificide volume fraction on account of Ce addition reduces the power of the sample resisting oxygen penetration.

关键词： oxidation resistance in-situ composite Nb-Si alloy rare earths

A Four-Wavelength All-Fiber Laser for Wavelength Division Multiplexing System

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Chinese Physics Letters 2001年第3期18卷 376-378页

作者： DING Lei KAI Gui-Yun XU Yan-Jun GUAN Bai-Ou YUAN Shu-Zhong DONG Xiao-Yi GE Chun-Feng Institute of Modern Optics Nankai UniversityTianjin 300071 College of Precision Instrument&Optoelectronics Tianjin UniversityTianjin 300072

A novel four-wavelength all-fiber laser based on fiber Bragg gratings is *** four wavelengths are 1555.8,1556.6,1557.4 and 1558.2 nm,*** output laser is1 mW in *** suppression ratio between adjacent wavelengths is>30 *** laser was applied in a wavelength division multiplexing(WDM)system and the 100 km transmission of 1.2 Gb/s nonreturn-to-zero code,1.2 Gb/s return-to-zero code,2.5 GHz analogue signal and 5 GHz analogue signal was realized with it.

关键词： Gb/s fiber laser