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Total Synthesis of (3.,6S)-(+)-3.7-Dimethyl-3.acetoxy-6-hydroxy-octa-1,7-diene

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Chinese Chemical Letters 1999年第2期10卷 111-112页

作者： Zuo Sheng LIU Jiong LAN Yu Lin LI(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry,Lanzhou university, Lanzhou, 73.000)Ya Cheng XING Wen CEN(department of Chemistry, qingdao university, {3., 266071. Natl. Lab. of Appl. Organ. Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 730000 China department of Chemistry Qingdao University Qingdao 266071 China

A total synthesis of(3., 6S)- (+)-3.7-dimethyl-3.acetoxy-6-hydroxy-octa-1,7-diene via the rearrangement of chiral 2,3.epoxy alcohol, with the system of Ph3., pyridine, I-2 and H2O, is described.

关键词： 2,3.epoxy alcohol rearrangement synthesis

Boundary conditions for the bending of a piezoelectric beam

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Science China(physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO Yang1, XU SiPeng2 & ZHAO BaoSheng3.1 College of Science, China Agricultural university, Beijing 100083. China 2 College of Engineering, Ocean university of China, qingdao {3. China 3.School of Mechanical Engineering, university of Science and Technology Liaoning, Anshan 114044, China College of Science China Agricultural University Beijing China College of Engineering Ocean University of China Qingdao China School of Mechanical Engineering University of Science and Technology Liaoning Anshan China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

Mixed boundary conditions for piezoelectric plates

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Science China(physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2 &ZHAO BaoSheng 3.1College of Science,China Agricultural university,Beijing 100083.China 2College of Engineering,Ocean university of China,qingdao {3.China 3.School of Mechanical Engineering,university of Science and Technology of Liaoning,Anshan 114044,China College of Science China Agricultural University Beijing China College of Engineering Ocean University of China Qingdao China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

Synergistic actions of complement and lysozyme in clearance of Escherichia coli from amphioxus Branchiostoma belcheri

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Progress in Natural Science:Materials International 2009年第2期19卷 179-185页

作者： Guangfeng Wang a,Shicui Zhang a,Zhimeng Zhuang b,Zhiping Wang a a department of Marine Biology,Ocean university of China,qingdao 266003.China b Yellow Sea Fisheries Research Institute,qingdao 266071.China department of Marine Biology Ocean University of China Qingdao 266003 China Yellow Sea Fisheries Research Institute Qingdao 266071 China

Amphioxus appears to lack free circulating blood cells. How it clears invading pathogens from its body remains unknown to date. We demonstrate here that amphioxus Branchiostoma belcheri is capable of efficiently eliminating the invading bacterium Escherichia coli from its humoral fluid,and the complement and lysozyme are both involved in the elimination of the invading pathogen. Both the com-plement and lysozyme act in concert against the invading bacterium,but the complement appears to play a more dominant role than the lysozyme.

关键词： Amphioxus Branchiostoma Complement Lysozyme Humoral fluids Anti-bacterial activity

Self-assembly structure formation on patterned InP surfaces

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Science China(Technological Sciences) 2009年第9期52卷 2732-2736页

作者： SU Ge1,2,CAO LiXin1 & LIU TianZhong3.1 Institute of Material Science and Engineering,Ocean university of China,qingdao 266100,China 2 Nanoscale physics Research Laboratory,School of physics and Astronomy,the university of Birmingham,Edgbaston,Birmingham B15 2TT,UK 3.College of Food Science and Engineering,Ocean university of China,qingdao 266003.China Institute of Material Science and Engineering Ocean University of China Qingdao China Nanoscale physics Research Laboratory School of Physics and Astronomy the University of Birmingham Edgbaston Birmingham UK College of Food Science and Engineering Ocean University of China Qingdao China

Self-assembly of polystyrene spheres guided by patterned n-type InP substrates has been investigated. InP surfaces were patterned using a variety of methods including wet chemical etching,sputter coating,thermal evaporation,and photo lithography. The self-assembly of polystyrene spheres depended on the appearance of patterns and was affected by the deposition techniques (sputter coating and thermal evaporation) of Au micro-squares. SEM and AFM were used to characterize the surface morphologies.

关键词： self-assembly polystyrene spheres pattern InP surface

Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science China(physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal university, Beijing 100875, China 2. physics department, Beijing Normal university, Beijing 100875, China 3. China Institute of Atomic Energy, Beijing 102413. China Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China China Institute of Atomic Energy Beijing China physics department Beijing Normal University Beijing China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 248Cm(26Mg,4n)270Hs, 244Pu(3.Si,4n)270Hs, 23.U(3.S,4n)270Hs and 226Ra(48Ca,4n)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(48Ca,4n)270Hs and 23.U(3.S,4n)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science China Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3.& WANG Huijun2 1. Nansen-Zhu International Research Center, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 100029, China 2. department of Atmospheric Science, Yunnan university, Kunming 650091, China 3. Graduate university of the Chinese Academy of Sciences, Beijing 100049, China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China department of Atmospheric Science Yunnan University Kunming China Graduate university of the Chinese Academy of Sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Ultrafast excitation relaxation in light-harvesting complex LH2 from *** 601

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Science China Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2, LIU Yuan3. LIU Weimin2, GUO Junhua1, XU Chunhe3.& QIAN Shixiong2 1. School of physics and Information Optoelectronics, Henan university, Kaifeng 475001, China 2. physics {3., Fudan university, Shanghai 20043., China 3. Shanghai Institute of Plant Physiology, Chinese Academy of Sciences, Shanghai 20003., China School of physics and Information Optoelectronics Henan University Kaifeng China physics department Fudan University Shanghai China Shanghai Institute of Plant Physiology Chinese Academy of Sciences Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2 from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783.nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.3. ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.

A study of two-dimensional magnetic polaron

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Science China(physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1, ZHANG Huaihong1, FENG Mang1,2 & WANG Kelin1,3.1. School of Science, Southwest university of Science and Technology, Mianyang 621010, China 2. Wuhan Institute of physics and Mathematics, Chinese Academy of Sciences, Wuhan 43.070, China 3. department of Modern physics, university of Science and Technology of China, Hefei 23.026, China School of Science Southwest University of Science and Technology Mianyang China Wuhan Institute of physics and Mathematics Chinese Academy of Sciences Wuhan China department of Modern physics University of Science and Technology of China Hefei China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.