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A direct and elementary proof of the stabilization for the wave equation with nonlinear internal damping

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A direct and elementary proof of the stabilization for the w...

第十九届中国控制会议

作者： Wei-Tao Zhang Institute of Systems Science, academy of Mathematics and Systems Science, The chinese academy of sciences, beijing 100080, china.

Using a technique in [4-7] and some integral inequalities due to Haraux and Komornik, one gave a direct and elementaty proof of the stabilization for the wave equation with nonlinear internal damping, extended and uni... 详细信息

关键词： wave equation internal damping stabilization

The　Fractal　Structures　of　the　Sample　Path　of　a　General　Subordinator　and　the　Random　Re-orderings　of　the　Cantor　Set

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Wuhan university Journal of Natural sciences 1997年第1期2卷 27-31页

作者： $$$$ Hu Xiaoyu Institute of Applied Mathematics, chinese academy of Science, beijing 100080,china Department of Mathematics, Central china Normal university, Wuhan 430070, china chinese academy of Science Institute of Applied Mathematics Beijing China (GRID:grid.9227.e) (ISNI:***) Central china Normal university Department of Mathematics Wuhan China (GRID:grid.411407.7) (ISNI:***)

In this paper we have found a general subordinator, X, whose range up to time 1, X([0,1)), has similar structure as random re orderings of the Cantor set K(ω).X([0,1)) and K(ω) have the same exact Hausdorff measure... 详细信息

关键词： Hausdorff measure packing measure subordinator random re ordering of the Cantor set

Photophysics studies of organic compounds Ⅷ.Interaction between excited singlet state of pyrene and aromatic amines

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chinese Journal of Chemistry 1991年第4期9卷 297-304页

作者： CHEN,Feng-Qi YU,Qun MENG,Xian-Juan SHOU,Han-Shen FAN,Mei-Gong Institute of Photographic Chemistry,The chinese academy of sciences,beijing 100101

The quenching processes of the excited singlet state of pyrene by triphenylamine,diphenyl- amine and N,N-dibenzylaniline in various solvents at room and lower temperature have been stu- died with both static state fluorescence spectroscopy and fluorescence lifetime *** the basis of experimental data,a preliminary quenching mechanism has been *** geome- trical configuration models of the exciplexes formed between the excited pyrene and aromatic ami- nes in nonpolar solvents were proposed.

关键词： Photophysics studies of organic compounds TPA

A Biochemical Study on Combined Treatment of Experimental Silicosis with Tetradrine-PVNO and Tetradrine-QOHP in Rats

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Biomedical and Environmental sciences 1995年第3期8卷 265-268页

作者： YU LAN ZOU CHANG-QI LI YU-RUI QU LEI XING KANG-JI AND DU QING-CHENG (Institute of Occupational Medicine, chinese academy of Preventive Medicine, beijing 100050, china) Institute of Occupational Medicine Chinese Academy of Preventive Medicine Beijing China

A better understanding is needed to explain the mechanism of therapeutic effect of combined use of tetradrine-PVNO and tetradrine-QOHP which play very important roles in treatment of silicosis. Blood prolidase (PLD), monoamine oxidase (MAO) and plasminogen (PLG) in silicotic rats after treatment with tetradrine-PVNO or tetradrine-QOHP were measured. The values obtained were compared with the untreated silicotic rats. It was found that the silicotic rats that received tetradrine-PVNO showed significant increase in PLD and decrease in PLG, but no significant change in MAO. The PLD in plasma of silicotic rats that received tetradrine-QOHP were elevated significantly, but PLG and MAO did not change appreciably. These findings suggest that the combined use of tetradrine-PVNO and tetradrine-QOHP can accelerate the degradation of collagen in silicotic rats

关键词： PVN A Biochemical Study on Combined Treatment of Experimental Silicosis with Tetradrine-PVNO and Tetradrine-QOHP in Rats

Adaptive control design of L2 -disturbance attenuation of multimachine power systems with SMES units by using Hamiltonian function method

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Adaptive control design of L2 -disturbance attenuation of mu...

第二十一届中国控制会议

作者： WANG Yu-zhen, LI Chun-wen, CHENG Dai-zhan ( Department of Automation, Tsinghua university, beijing, 100084, china Institute of Systems Science, chinese academy of sciences, beijing, 100080, china)

＜正＞By using Hamiltonian function method, this paper investigates adaptive control design of L2 -disturbance attenuation of an n -machine power system with m SMES （superconducting magnetic energy storage） units, and proposes a decentralized control scheme for the adaptive case of parameter perturbations. Firstly, the n -machine power system with the m SMES units is expressed as a dissipative Hamiltonian system by using a pre-feedback control. Then the stability of the achieved dissipative Hamiltonian system is studied. Thirdly, this paper investigates the energy-based adaptive control design of L2 -disturbance attenuation of the system with parameter perturbations.

关键词： n -machine power system SMES dissipative Hamiltonian realization L2 - disturbance attenuation energy-based adaptive control

DAPHNIPHYLLUM ALKALOIDS

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DAPHNIPHYLLUM ALKALOIDS

中药与天然药高峰论坛暨第十二届全国中药和天然药物学术研讨会

作者： Haifeng Wu~(1,*),Xiaopo Zhang~1,Guoxu Ma~1,Lisheng Ding~2,Shilin Chen~(1,3),Xudong Xu~(1,*) 1 Institute of Medicinal Plant Development,chinese academy of Medical sciences and Peking Union Medical College,beijing 100193,china 2 Chengdu Institute of Biology,chinese academy of sciences,Chengdu 610041,china 3 Institute of Chinses Materia Medica,china academy of chinese Medical sciences,beijing 100700, china

The unique polycyclic fused ring systems of Daphniphyllum alkaloids,along with their extensive bioactivities,make this family of alkaloids especially attractive targets for total synthesis and biogenetic *** particular,successive discoveries of new alkaloids with unprecedented skeletons in recent years have made great contribution to structural diversities of alkaloids elaborated by plants of the genus *** the end of 2008,more than 200 alkaloids belonging to 14 different skeletal types have been isolated from different parts of plants of thirteen Daphniphyllum *** alkaloids show cytotoxic,antioxidant,vasorelaxant and anti-platelet activating factor(PAF)*** plausible biosynthetic pathways for Daphniphyllum alkaloids have been proposed and biomimetic total syntheses of some alkaloids *** provide an update of the previous reviews published in 2009,chemical structures,biosynthesis,syntheses and pharmacological activities of Daphniphyllum alkaloids reported in the latest years are presented in this *** 2009 and 2012,additional fifty-one novel alkaloids have been isolated and *** them,some possess unprecedented *** state-of-the-art total syntheses through cascade reactions were completed.

关键词： alkaloids Daphniphyllum biosynthesis total synthesis pharmacological activities

The existing time of Sihetun vertebrate in western Liaoning,china——Evidence from U-Pb dating of zircon

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The existing time of Sihetun vertebrate in western Liaoning,...

中国科学院地质与地球物理研究所2001学术年会

作者： WANG Songshan~1,WANG Yuanqing~2, HU Huaguang~1 & LI Huimin~3 1.Institute of Geology and Geophysics,chinese academy of sciences, beijing 100029,china 2.Institute of Vertebrate Paleontology and Paleoanthropology,chinese academy of sciences,beijing 100044,china 3.Tianjin Institute of Geology and Mineral Resources,Tianjin 300170, china

In different opinions,the stratigraphic time of the feathered dinosaurs and eariy birds in Sihetun and its neighboring areas in Beipiao,western Liaoning is appointed to different epoches of eras,such as Late Jurassic,Early Cretaceous and Late Jurassic-Early *** the recently dating data are still very different This note first reported the U-Pb age of(125.2±0.9) Ma ofzircon separated from tuff of Sihetun vertebrates *** age reveals that Sihetun vertebrate belongs to Early *** method is more objective,because of the strong ability of disturbance resistance and high U-Pb blocking temperature of zircons.

关键词： Sihetun vertebrates tuff zircon U-Pb dating

Recursive Subspace Identification for Closed-loop Systems

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Recursive Subspace Identification for Closed-loop Systems

第二十六届中国控制会议

作者： Jiang Yueping,Fang Haitao academy of Mathematics and Systems Science,chinese academy of sciences,beijing 100080,P.R.china

The problem of recursive subspace identification of state-space models in closed-loop is considered in this paper.A new recursive algorithm based on Stochastic Approximation-Principal Component Analysis（SA-PCA） is proposed to estimate a basis of the extended observability matrix in the noise-free *** algorithm is evaluated by a simulation study.

关键词： State-space models Closed loop Recursive subspace identification Principal component analysis.

Synthesis of Amurensin H, a New Resveratrol Dimer from the Roots of Vitis Amurensis

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chinese Chemical Letters 1999年第10期10卷 817-820页

作者： Kai Sheng HUANG Mao LIN Ying Hong WANG(Institute of Materia Medica. chinese academy of Medical sciencesand Peking Union Medical College, beijing 100050) Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College

Amurensin H(1) is a new resveratrol dimer isolated from the roots of Vitis amurensis Rupr. Its structure was determined by spectroscopic methods. II was synthesized from resveratrol with an oxidative coupling reaction... 详细信息

关键词： synthesis amurensin H Vitis amurensis resveratrol oxidative coupling reaction