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An Asymptotic Solvable Multiple “Look-Ahead” Model with Multi-weight

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Communications in Theoretical Physics 2007年第12期48卷 1088-1092页

作者： SHI Wei~1 CHEN Ning-Guo~1 and XUE Yu~(1,2)~1 institute of Physical Science and Engineering,Guangxi University,Nanning 530004,china~2 Shanghai institute of applied mathematics and Mechanics,Shanghai University,Shanghai 200072,china institute of Physical Science and Engineering Guangxi University Nanning 530004 China Shanghai institute of applied mathematics and Mechanics Shanghai University Shanghai 200072 China

A type of multiple "look-ahead" car-following models is studied by nonlinear *** mKdV equationto describe density wave of traffic jamming is *** result indicates that the behavior of multiple "look-ahead"is in favor of stability enhancement of traffic ***,the traffic flow can reach the most stable case viaadjustment of the parameter of weight functions m=3.

关键词： traffic flow car-following model nonlinear analysis mKdV equation

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超线性与二次收敛的序列方程组可行方法

数学学报（中文版） 2002年第6期45卷 1137-1146页

作者：简金宝赖炎连张可村广西大学数学与信息科学系广西南宁530004 中国科学院数学与系统科学研究院应用数学研究所北京100080 西安交通大学理学院陕西西安710049

本文讨论不等式约束规划问题,给出一个线性方程组与辅助方向相结合的新可行算法,算法用一种新型的直线搜索产生步长.在一定条件下,当k充分大后,求方向dk每次只需解一个线性方程组.文中证明了算法的全局收敛性与超线性的收敛速度以及二... 详细信息

本文讨论不等式约束规划问题,给出一个线性方程组与辅助方向相结合的新可行算法,算法用一种新型的直线搜索产生步长.在一定条件下,当k充分大后,求方向dk每次只需解一个线性方程组.文中证明了算法的全局收敛性与超线性的收敛速度以及二次收敛性,并给出了方法初步的数值试验.

关键词：超线性二次收敛序列方程组可行方法不等式约束非线性规划

BIOTRANSFORMATION　OF　2α，5α，10β，14β－TETRA－ACETOXY－4（20），11－TAXADIENE　BY　THE　FUNGIJS　CUNNINGHAMELLA　ECHINULATA

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chinese Chemical Letters 1996年第6期7卷 543-544页

作者： Shang Hut HU Xu Fang TIAN Wei Hua ZHU and Qi Cheng FANG(institute of Materia Medica, chinese academy or Medical sciencesand Peking Union Medical College, beijing 1000050) institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050

?5α,10β,14β-Tetra-acctoxy-4(20).11-taxadicne (1) could be regioselectively transfonnedinto 6α 10β-dihydroxy-2α,5α,14β-triacetoxy-4(20). 11- taxadiene (2) by Cunninghamella echinnlata infair yield. 6βM.10β-Dihydroxy-2α,5α,14β-triacet 11-taxadienc (3). 10β-hydroxy-2α,5α,14β-triacetoxy-4(20).11-taxadiene (4), 10 β-hyboxy-4β,20-epoxy -2α,5α,14β-triacetoxy- tax - 11- ene (5)asminor prpducts were also isolated

关键词： TETRA OF FUNGIJS THE CUNNINGHAMELLA ECHINULATA BY ACETOXY BIOTRANSFORMATION

NUMERICAL ANALYSIS OF SHEAR-BAND BIFURCATION

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Acta Mechanica Sinica 1990年第1期6卷 22-28页

作者： Li Guochen, institute of Mechanics, Academia Sinica, beijing, china institute of Mechanics Academia Sinica Beijing China

A numerical analysis of bifurcation in shear-band pattern is presented to help understand the distributions of the velocity variation in the shear band. Comparison with the results of analytic method indicates that: (1) the critical strain is irrelevant to the relative width of the shear band; (2) the variations along the direction normal to the band have indeed the controlling effect whilst the effect of variations along the tangential direction is negligible.

关键词： shear band bifurcation diffuse analysis

Identification and characterization of a novel isoform of hepatopoietin

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World Journal of Gastroenterology 2002年第2期8卷 353-356页

作者： Jun Lu Wei-Min Cai,institute of Infectious Disease,First Affiliated Hospital,Medical SchooI,Zhejiang University,Hangzhou 310003 china Wang-Xiang Xu Yi-Qun Zhan Xiao-Lin Cui Fu-Chu He Xiao-Ming Yang,institute of Radiation Medicine,academy of Military Medical sciences,beijing 100850,china institute of infectious Disease First Affiliated Hospital Medical School Zhejiang University Hangzhou 310003 China.

AIM: To isolate a novel isoform of human HPO (HPO-205) from human fetal liver Marathon-ready cDNA and characterize its primary biological function. METHODS: 5'-RACE (rapid amplification of cDNA 5' ends) was used to isolate a novel isoform of hHPO in this paper. The constructed pcDNA(HPO-205), pcDNA(HPO) and pcDNA eukaryotic expression vectors were respectively transfected by lipofectamine method and the stimulation of DNA synthesis was observed by (3)H-TdR incorporation assay. Proteins extracted from different cells were analyzed by Western blot. RESULTS: A novel isoform of hHPO (HPO-205) encoding a 205 amino acid ORF corresponding to a translated production of 23 kDa was isolated and distinguished from the previous HPO that lacked the N-terminal 80 amino acids. The dose-dependent stimulation of DNA synthesis of HepG2 hepatoma cells by HPO-205 demonstrated its similar biological activity with HPO in vitro. The level of MAPK (Mitogen-activated protein kinase) phosphorylation by Western blot analysis revealed that HPO-205 might have the stronger activity of stimulating hepatic cell proliferation than that of HPO. CONCLUSION: A novel isoform of hHPO (HPO-205) was isolated from hepatic-derived cells. The comparison of HPO-205 and HPO will lead to a new insight into the structure and function of hHPO, and provide the new way of thinking to deeply elucidate the biological roles of HPO/ALR.

关键词： Amino Acid Sequence Cell Division Cell Fractionation Enzyme Activation Hepatocyte Growth Factor purification Humans Liver Mitogen-Activated Protein Kinases Molecular Sequence Data Open Reading Frames Protein Isoforms Sequence Alignment Tumor Cells, Cultured

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移动数据库系统乐观事务处理策略

计算机研究与发展 2002年第10期39卷 1379-1387页

作者：丁治明孟小峰王珊中国科学院计算技术研究所北京100080 中国人民大学数据与知识工程研究所北京100872

在移动数据库系统中 ,计算平台的移动性、频繁的断接性以及长事务等特性使得传统的事务处理模式不再适用 .为了解决移动数据库中的事务处理问题 ,提出了一种新的移动事务处理模型——乐观两阶段提交移动事务模型 ( O2 PC-MT) .该模型采... 详细信息

在移动数据库系统中 ,计算平台的移动性、频繁的断接性以及长事务等特性使得传统的事务处理模式不再适用 .为了解决移动数据库中的事务处理问题 ,提出了一种新的移动事务处理模型——乐观两阶段提交移动事务模型 ( O2 PC-MT) .该模型采用乐观并发控制与两阶段提交协议相结合的方法 ,对移动事务的长事务特性提供了灵活与有效的支持 ;此外 ,该模型允许移动计算机分多次发送事务操作 ,且在事务执行的过程中可以任意移动 ,从而提供了对交互式事务及随意移动性的支持 .实验结果表明 ,与基于两段锁协议及其变形的其它移动事务处理模型相比 ,O2

关键词：移动数据库系统乐观事务处理策略移动计算乐观并发控制

Characteristics of fluid inclusion planes and dynamical mechanism of structure-fluid-ore-forming processes in Yindongpo gold deposit, Henan Province, china

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chinese Science Bulletin 1999年第S2期44卷 150-152页

作者： WEI Changshan~1, ZHAI Yusheng~2 and GHI Sanchuan~2 1. Yichang institute of Geology and Mineral Resources, chinese academy of Geoscience, Yichang 443003, china 2. china University of Geosciences, beijing 100083, china Yichang institute of Geology and Mineral Resources Chinese Academy of Geoscience Yichang 443003 China china University of Geosciences Beijing 100083 China

THE Yindongpo gold deposit, situated in northern Tongbei County, northern Qinling orogenic belt, is alarge-scale one controlled by the Heqianzhuang anticline that plunges northwestwards and dips northeastwards. The ore-bodies locates in the carbon layers belonging to the Neoproterozoic Waitoushan *** ore-forming periods can be distinguished: the pre-Mesozoic epithermal mineralization in primary sediment with metamorphic superposition and the Mesozoic epithermal-mesothermal mineralization related totectonomagmatic activities. The principal ore-forming period can be divided into four stages. The ore bodies consist of networked and brecciated quartz veins. Gold is mainly rich in the veinlet-type quartz veinsthat formed during the diagentic-metamorphism or syn-metamorphic hydrothermal period, but a little inthe coarse veins related to later tectonomagmatic activities. The phenomenon that the fracturing degree

关键词： fluid inclusion planes dynamical mechanism structure-fluid-ore-forming processes gold deposit Yindongpo Henan.

Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2, LU Yuanzheng1,2,3 & XU Daoyi4 1. Research institute of Petroleum Exploration and Development, beijing 100083, china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, beijing 100083, china 3. china University of Geosciences, beijing 100083, china 4. institute of Geology, china Earthquake Administration, beijing 100029, china Research institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china University of Geosciences Beijing China institute of Geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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西藏经济真菌资源

山地研究 1993年第2期11卷 105-112页

作者：卯晓岚中国科学院微生物研究所北京100084

西藏真菌资源丰富,目前已知食用菌352种,107属,34科。药用菌163种,82属,41科,其中用于抗癌和试验抗癌的93种,有毒菌97种,36属,20科。外生菌根菌107种,29属,19科。木腐菌47种,30属,13科。地处世界屋脊的西藏,还孕育了多种多样的高山真菌... 详细信息

西藏真菌资源丰富,目前已知食用菌352种,107属,34科。药用菌163种,82属,41科,其中用于抗癌和试验抗癌的93种,有毒菌97种,36属,20科。外生菌根菌107种,29属,19科。木腐菌47种,30属,13科。地处世界屋脊的西藏,还孕育了多种多样的高山真菌,有待进一步考察研究和开发利用。

关键词：西藏真菌资源食用菌药用菌