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Order-disorder Transformation for TiAl with L1_0 Structure at Stoichiometrical Composition

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Rare Metals 2001年第3期20卷 147-151页

作者： Timothé e Nsongo, Xiaodong Ni,Guoliang Chen,Keh-Minn Chan 1) State Key Laboratory for Advanced Metals and Materials, university of Science and Technology beijing, beijing 100083, china {4. Faculty of Science (Physics Department, P.O. Box 69 Brazzaville, Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China Fac Sci Dept Phys Brazzaville Rep Congo Univ Sci & Technol beijing Dept Phys Beijing 100083 Peoples R China W Virginia Univ Dept Mech & Aerosp Engn Morgantown WV 26506 USA

The embedded atom method (EAM) was used to study the order-disorder transformation in gamma -TiAl alloy with L1(0). structure at stoichiometrical composition, and the effect of lattice constants was also investigated. It was found that the gamma -TiAl alloy at stoichiometrical composition exhibits a second-order transition, and the relations between lattice constants a, c and the long-range order sigma are not linear. The lattice constant a decreases whereas c increases with the increase of the long-range order parameter. In this case the ordering induces the transformation from cubic to tetragonal. The change of the lattice constant during the ordering processes can be interpreted in terms of bond length.

关键词： order-disorder transformation TiAl long-range order intermetallic

Syntheses, properties and structures of copper and nickel complexes of 6,7-dihydro-5H-1,4.dithiepin-2.3-dithiolate

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Chinese Journal of Chemistry 1994年第3期12卷 248-257页

作者： YAO, Tian-Ming YOU, Xiao-ZengCoordination Chemistry Institute, State Key Laboratory of Coordination Chemistry, Nanjing university,Nanjing 2.0008, chinaYANG, Qing-ChuanChemistry Department, {2. university, {2. 100871, china 1Coordination Chemistry Institute State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210008 China2Chemistry Department Beijing University Beijing 100871 China

The reaction of CuCl2.2.2. or NiCl2.6H2. with K2.C5H6S4. [potassium salt of 6,7-dihydro-5H-1,4.dithiepin-2.3-dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4.2.- or [Ni(C5H6S4.2.- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4.2.0 = [M(C5H6S4.2.1-= [M(C5H6S4.2.2.. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4.][Ni(C5H6S4.2. belongs to monoclinic space group P2./c with a=17.576(5), 6=10.883(2., c=17.773(4. A,B=91.07(2.0, Z=4. and o(calcd.)=1.34. g/cm3. Final result is R=0.059 for 2.59 reflections. The NiS4.core exhibits square planar coordination with average Ni-S bond length of 2.134.5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.4.0} A. The solid powder ESR spectrum of the nickel complex shows three broadening signals at g1=2.097, g2.2.04.0} g3=2.02.. Magnetic susceptibility data for [Bu4.][Ni(CgH6S4.2. reveal enhanced anti-ferromagnetic interaction.

关键词： Dithiolene complex copper nickel single crystal.

Interface Assets:Uncontrolled Resources of Competitive Advantage

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清华大学学报（哲学社会科学版） 2009年第S1期24卷 81-88页

作者： GUO Guang-rui(School of Economics and Management,Tsinghua university,beijing 100084.{2.)

The purpose of strategic management is to produce knowledge of,to understand and to explain how firms achieve and sustain competitive *** the assumption that something beyond firm-controlled resources and industry structure contribute significantly to firm's competitive advantage as well,I propose a new construct of interface assets to integrate all the resources beyond firm-controlled resources and industry structure.I examine the attributes of interface assets and propose four assumptions about interface assets.I also develop a framework that illustrates how interface assets contribute to competitive ***,I conclude the article by discussing the theoretical and practical implication of the interface assets model.

关键词： interface assets competitive advantageAbout the Author: GUO Guang-rui,School of Economics and Management,Tsinghua university,Ph.D.Candidate,research direction: strategic management,competitive advantage

Sequence Stratigraphy and Relative Sea Level Changes in Sinian System of Yichang, Hubei Province

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Journal of Earth Science 1996年第1期15卷 29-37页

作者： Wang Ziqiang (Department of Geology and Mineral Resources, china university of Geo{2., beijing 100083) Gao Linzhi (Institute of Geology, Chinese {4. of Geological {2., beijing 10003.) Zhang Linghua Jiang Ganqing Zhang Chuanheng Yin Yong (Dep

The study on outcrop sequence stratigraphy of the Sinian section in the Yangtze Gorges an important step in the comprehensive stratigraphy for the Sinian stratotype. In this paper, the base of the Nantuo tillite is selected as the bottom boundary of the Sinian, and the top of the Baimatuo Member of the Dengying Formation is taken as the top boundary. The Sinian lasted from 74. the to 570 Ma. According to the features of sequence boundary facies and the parasequence sets, two supersequences are recognized in the Sinian with six sequences. In this paper, the authors discuss the correlation of those sequences. On the basis of the subsidence rate and the thickness of decompressed deposits, the authors discuss the mechanism of tectonic and sedimentation of the Dengying Formation and the features of high-frequency rhythms as well as the 3rd-order sequences in the Yangtze Gorges.

关键词： Sinian System sequence supersequence stacking parasequence set.

Effects of Chinese Milk Vetch (Astragalus sinicus L.) Residue Incorporation on CH4.and N2. Emission from a Double-Rice Paddy Soil

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Journal of Integrative Agriculture 2012年第9期11卷 1537-1544页

作者： ZHU Bo1,YI Li-xia1, HU Yue-gao1, ZENG Zhao-hai1, TANG Hai-ming2. YANG Guang-li2.and XIAO Xiao-ping2.1 College of Agronomy and Biotechnology, china Agricultural {4., {2. 100193, P.R.china 2.Hunan Soil and Fertilizer Institute, Changsha 4.012., P.R.china [a] College of Agronomy and Biotechnology China Agricultural University Beijing 100193 P.R. China [b] Hunan Soil and Fertilizer Institute Changsha 410125 P.R. China

Methane (CH 4.) and nitrous oxide (N 2.O) emissions from paddy soils have seldom been estimated when leguminous green manure is applied as a nitrogen source. In this paper, gas fluxes were measured by using a pot sampling device combined with a static chamber method to estimate the effects of Chinese milk vetch (Astragalus sinicus L., CMV) on CH 4.and N 2.O emissions and their integrated global warming potentials (GWP) in a double-rice cropping system. Four treatments (no nitrogen fertilizer, NF; urea as chemical fertilizer, CF; CMV incorporation, MV; 50% CMV incorporation and 50% urea, MVCF) were established. CH 4.flux peaked on the 15th d after treatment application. Total season CH 4.emission was increased by MV and MVCF by 370 and 2.9%, 152.and 66%, when compared with NF and CF, respectively. Most of the increased CH 4.was emitted in the first two months after incorporation of CMV. N 2.O emission from CF was 17- and 5.6-fold higher than that from MV and MVCF, respectively. Application of CMV restricted N 2.O emission caused by the application of urea. Improved CMV residue management was needed to minify CH 4.emission induced by the input of organic material. Despite the highest GWP being found in MV, we recommend CMV, when applied as an N source in paddy fields, as a potential mitigation tool for greenhouse gas emissions.

关键词： Chinese milk vetch double-rice global warming potential methane nitrous oxide

Key Problems of Cold Power Spinning of Ti-15-3 Alloy

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Journal of Materials Science & Technology 2001年第1期17卷 125-126页

作者： Debin SHAN Yan LU and Ping LI School of Materials Science and Engineering, Harbin institute of Thchnology, Harbin 150001, china Yi XU Institute of Metal Research, Chinese academy of {2., Shenyang 110015, china Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

The key problems of cold power spinning of Ti-15-3 alloy are studied. Reasonable billet preparation methods are presented to improve crystal structure and avoid crack of billet. Influences of original wall thickness, reduction rate and feed rate on expanding in diameter are analyzed and some methods to prevent expanding in diameter are given.

关键词： Ti Key Problems of Cold Power Spinning of Ti-15-3 Alloy

Antiviral therapy with nucleos(t)ide analogues for severe chronic hepatitis B

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Hepatobiliary & Pancreatic Diseases International 2009年第4期8卷 438-439页

作者： Fu-Kui Zhang, Liver Research Center, beijing Friendship Hospital, Capital Medical university, beijing 100050,china Capital Med Univ Beijing Friendship Hosp Liver Res Ctr Beijing 100050 Peoples R China

To the Editor:I read the paper by Chen et al[1]with great *** authors performed a retrospective study to evaluate the short-term efficacy of antiviral therapy with

关键词： CHB HBV Antiviral therapy with nucleos t)ide analogues for severe chronic hepatitis B

Proteomic analysis of the response of Liangyoupeijiu (a super high-yield hybrid rice) seedlings to cold stress

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Proteomic analysis of the response of Liangyoupeijiu (a supe...

Thermal stability of nanostructured NiCrC coating prepared by HVAF spraying of cryomilled powders

首届全国蛋白质组学学术研讨会

作者： Yang Pingfang, Jing Yuxiang, Shen Shihua, Kuang Tingyun, Key laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, Chinese academy of sciences, {2., china {4. College of Chinese academy of sciences, {2., china

Liangyoupeijiu is a super high-yield hybrid rice bred recently. In spite of its advantage in yield, it is sensitive to cold, which constrains its popularization. We performed a 4.cold treatment on Liangyoupeijiu seedlings, then extracted the leaf proteins. After 2.dimensional gel electrophoresis (2.DE) separation and Matrix assisted Laser Desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, a series of differentially displayed proteins were identified. Some metabolism-associated proteins were found among the down-regulated proteins, such as caramoyl phosphate synthetase, transketolase 1, dihydrolipoamide dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase. As for the up-regulated proteins, they include FtsH-like protein plastid fusion and/or translocation factor (Pftf) and actin that are negative for rice growth, although stress resistant proteins such as nucleoside diphosphate kinase I were identified. Our results indicate that cold may inhibit Liangyoupeijiu growth through decreasing metabolism activity and damaging cell structure.

关键词： Oryza sativa Hybrid rice Cold stress Proteome

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Rare Metals 2008年第4期27卷 418-424页

作者： CUI Hua TAO Kai ZHOU Xianglin ZHANG Jishan School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China State Key laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Thermal stability of nanostructured NiCrC coating prepared by high velocity air-fuel （HVAF） spraying of cryomilled feedstock powders was investigated. Transmission electron microscopy （TEM）, differential scanning calorimetry （DSC）, and X-ray diffraction （XRD） were utilized for characteristic analysis. Recrystallization and normal grain growth occur when isothermal treatment is performed at 92. K （0.55 TM） for up to 100 h, and the average grain size increases from initial 4. nm for as-deposited state to around 100 nm for nearly equilibrium state. Isochronal treatment at 82. K and 102. K was also conducted for comparison. Accordingly, for 0.4. to 0.61 T/TM, the time exponent n deduced from D^1/n - D0^1/n = kt increases from 0.15 to 0.30. The observed high thermal stability is attributed primarily to a Zener pinning mechanism arising from the fine Cr2.3 dispersions and the solute drag effect as well.

关键词： nanostructure coatings grain growth heat treatment high velocity air fuel (HVAF) cryomilling