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| 1 | Technical framework for Internetware: An architecture centric approach显示文摘Being a new software paradigm evolved by the Internet, Internetware brings many challenges to the traditional software methods and techniques. Sponsored by the national basic research program (973), researchers in China have developed an architecture centric technical framework for the definition, incarnation and engineering of Internetware. First of all, a software model for Internetware is defined for what to be, including that Internetware entities should be packaged as components, behaving as agents, interoperating as services, collaborating in a structured and on demand manner, etc. Secondly, a middleware for Internetware is designed and implemented for how to be, including that Internetware entities are incarnated by runtime containers, structured collaborations are enabled by runtime software architecture, Internetware can be managed in a reflective and autonomic manner, etc. Thirdly, an engineering methodology for Internetware is proposed for how to do, including the way to develop Internetware entities and their collaborations by transforming and refining a set of software architectures which cover all the phases of software lifecycle, the way to identify and organize the disordered software assets by domain modeling, etc. | YANG FuQing1,2, Lü Jian3,4 & MEI Hong1,2 1 Key Laboratory of High Confidence Software Technologies (Peking University), Ministry of Education, Beijing 100871, China 2 School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China 3 State Key Laboratory for Novel Software Technology, Nanjing 210093, China 4 Department of Computer Science and Technology, Nanjing University, Nanjing 210093, China | 2008 | Science in China(Series F)2008，51，6： | 33 |
| 2 | Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in China显示文摘Bemisia tabaci(Gennadius) biotype B,called a 'superbug',is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity,evolution and molecular eco-adaptation of biotype B.Furthermore,it provides a base for sustainable management of B.tabaci using biological and ecological measures. | WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2,LUO Chen3,CHU Dong4,ZHANG YouJun4,ZANG LianSheng2,JIU Min2,Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4,ZHANG Fan3,ZHANG QingWen5,LIU WanXue1,LIANG Pei5,LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Acadeny of Agriculture Sciences,Beijing 100094,China 2 Institute of Applied Entomology,Zhejiang University,Hangzhou 310029,China 3 Institute of Plant and Environment Protection,Beijing Academy of Agricultural and Forestry Sciences,Beijing 100089,China 4 Institute of Vegetables and Flowers,Chinese Acadeny of Agricullare Sciences,Beijing 100081,China 5 Department of Entomology,China Agriculture University,Beijing 100094,China | 2009 | Science China(Life Sciences)2009，52，1： | 30 |
| 3 | Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,Sichuan Basin,southwest China显示文摘As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,China. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3 categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2) the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3) the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt. | TANG LiangJie1,2,3,YANG KeMing4,JIN WenZheng1,2,3,L ZhiZhou4 & YU YiXin1,2,3 1 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 2 Key Laboratory for Hydrocarbon Accumulation Mechanism,China University of Petroleum,Ministry of Education,Beijing 102249,China 3 Basin and Reservoir Research Center,China University of Petroleum,Beijing 102249,China 4 Southwest Division Company,SINOPEC,Chengdu 610081,China | 2008 | Science China Earth Sciences2008，51，S2： | 18 |
| 4 | Influence of Ordovician carbonate reservoir beds in Tarim Basin by faulting显示文摘The quality of the Ordovician carbonate reservoir beds in the Tarim Basin is closely related to the development of secondary pores,fractures and cavities. Karstification is important in improving the properties of reservoir beds,and karstification related to unconformity has caught wide attention. Compared with the recent research on the unconformity karst reservoir bed improvement,this paper shows a new way of carbonate reservoir bed transformation. Based on field survey,core and slices observation,transformation of Ordovician carbonate reservoir beds by faulting can be classified into three types: (1) Secondary faults and fracturs generated by faulting improved carbonate reservoir bed properties,which were named the Lunnan or Tazhong82 model; (2) upflow of deep geothermal fluids caused by faulting,with some components metasomatizing with carbonate and forming some secon-dary deposit,such as fluorite. It can improve carbonate reservoir bed properties obviously and is named the Tazhong 82 model; and (3) the faulting extending up to the surface increased the depth of supergene karstification and the thickness of reservoir bed. It is named the Hetianhe model. Trans-formation effect of carbonate reservoir beds by faulting was very significant,mainly distributed on the slopes or on the edge or plunging end of the uplift. | L XiuXiang1,2,YANG Ning1,2,ZHOU XinYuan3,YANG HaiJun3 & LI JianJiao1,2 1 Faculty of Natural Resource & Information Technology,China University of Petroleum,Beijing 102249,China 2 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 3 Tarim Oilfield,PetroChina,Korla 841000,China | 2008 | Science China Earth Sciences2008，51，S2： | 13 |
| 5 | Tidally induced upwelling off Yangtze River estuary and in Zhejiang coastal waters in summer显示文摘MASNUM wave-tide-circulation coupled numerical model (MASNUM coupled model, hereinafter) is de-veloped based on the Princeton Ocean Model (POM). Both POM and MASNUM coupled model are ap-plied in the numerical simulation of the upwelling off Yangtze River estuary and in Zhejiang coastal waters in summer. The upwelling mechanisms are analyzed from the viewpoint of tide, and a new mechanism is proposed. The study suggests that the tidally inducing mechanism of the upwelling in-cludes two dynamic aspects: the barotropic and the baroclinic process. On the one hand, the residual currents induced by barotropic tides converge near the seabed, and upwelling is generated to maintain mass conservation. The climbing of the residual currents along the sea bottom slope also contributes to the upwelling. On the other hand, tidal mixing plays a very important role in inducing the upwelling in the baroclinic sea circumstances. Strong tidal mixing leads to conspicuous front in the coastal waters. The considerable horizontal density gradient across the front elicits a secondary circulation clinging to the tidal front, and the upwelling branch appears near the frontal zone. Numerical experiments are de-signed to determine the importance of tide in inducing the upwelling. The results indicate that tide is a key and dominant inducement of the upwelling. Experiments also show that coupling calculation of the four main tidal constituents (M2, S2, K1, and O1), rather than dealing with the single M2 constituent, im-proves the modeling precision of the barotropic tide-induced upwelling. | L XinGang1,2,3,4, QIAO FangLi1,2, XIA ChangShui1,2 & YUAN YeLi1,2 1 The First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China 2 Key Laboratory of Marine Science and Numerical Modeling (MASNUM), State Oceanic Administration, Qingdao 266061, China 3 Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China 4 Graduate University of the Chinese Academy of Sciences, Beijing 100039, China | 2007 | Science China Earth Sciences2007，50，3： | 9 |
| 6 | Two-dimensional thermoelasticity solution for functionally graded thick beams显示文摘Two-dimensional thermoelasticity analysis of functionally graded thick beams is presented using the state space method coupled with the technique of differential quadrature. Material properties vary continuously and smoothly through the beam thickness, leading to variable coefficients in the state equation derived from the elasticity equations. Approximate laminate model is employed to translate the state equation into the one with constant coefficients in each layer. To avoid numerical instability, joint coupling matrices are introduced according to the continuity conditions at interfaces in the approximate model. The differential quadrature procedure is applied to discretizing the beam in the axial direction to make easy the treatment of arbitrary end conditions. A simply-supported beam with exponentially varying material properties is considered to validate the present method. Numerical examples are performed to investigate the influences of relative parameters. | Lü Chaofeng1, CHEN Weiqiu1 & ZHONG Zheng2 1. Department of Civil Engineering, Zhejiang University, Hangzhou 310027, China 2. Key Laboratory of Solid Mechanics of Ministry of Education, School of Aerospace Engineering and Ap- plied Mechanics, Tongji University, Shanghai 200092, China | 2006 | Science China(Physics,Mechanics & Astronomy)2006，49，4： | 8 |
| 7 | A heuristic path-estimating algorithm for large-scale real-time traffic information calculating显示文摘As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions. | L WeiFeng1,ZHU TongYu1,WU DongDong2,DAI Hong3 & HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang University,Beijing 100083,China 2 Beijing Transportation Information Center,Beijing 100055,China 3 College of Arts & Science,Beijing Union University,Beijing 100083,China | 2008 | Science China(Technological Sciences)2008，51，S1： | 7 |
| 8 | LA-ICP-MS U-Pb Zircon Geochronology,Geochemistry and Kinetics of Wenquan Ore-Bearing Granites from Western Qinling,China显示文摘As we know there is a famous East Qinling-Dabie molybdenum belt in china,where many molybdenum deposits located such as super giant Jinduicheng,Sandaozhuang,Shangfanggou and Nannihu molybdenum deposits(Li,2008) ;The molybdenum mineralization in the East Qinling-Dabie belt clusters into three groups or mineralization pulses:233-221,148-138 and 131-112 Ma(Mao et al,2008). | CAO Xiao-feng1,2,Lü Xin-biao1,2,CHEN Chao2,LIU Shen-tai2,ZHANG Ping2,SU Yu-yun2,MEI Wei2,ZHANG Bin3(1. State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China 2. China Resource Department,China University of Geosciences,Wuhan 430074,China) | 2009 | 矿物学报2009，29，S1： | 6 |
| 9 | The relationship between viscosity and glass forming ability of Al-(Ni)-Yb alloy systems显示文摘The dynamic viscosity of Al-Yb and Al-Ni-Yb superheated melts was measured using a torsional oscillation viscometer. The results show that the temperature dependence of viscosity fits the Arrhenius law well and the fitting factors are calculated. The amorphous ribbons of these alloys were produced by the melt spinning technique and the thermal properties were characterized by using a differential scanning calorimetry (DSC). E (the activation energy for viscous flow), which reflects the change rate of viscosity, has a good negative relation with the GFA in both Al-Yb and Al-Ni-Yb systems. However, there is no direct relation between liquidus viscosity (ηL) and GFA. The superheated fragility M can predict GFA in Al-Yb or Al-Ni-Yb alloy system. | JIA Ran, BIAN XiuFang, Lü XiaoQian, SONG KaiKai & LI XueLian Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，3： | 6 |
| 10 | Effects of cooling rates on the mechanical properties of a Ti-based bulk metallic glass显示文摘Mechanical properties of the glassy specimens fabricated at different cooling rates with a composition of Ti40Zr25Cu12Ni3Be20 were systematically investigated. It was confirmed that faster cooling rates caused not only a larger amount of frozen-in free volume but also a higher glass transition temperature in the bulk glassy alloy. Increase in the free volume was found to favor plastic deformation and then to give rise to larger compressive plasticity, whilst the rise in the glass transition temperature seemed to be closely related to the higher yield strength. Moreover, the increase of yield strength and plasticity induced by fast cooling rates may also be associated with the residual stress generated during the fabrication process. Our results suggest that the deformation behavior of bulk metallic glasses is sensitive to various factors and influences from the other factors should be excluded as far as cooling-rate effects on bulk metallic glasses are considered. | XIAO YueHua, WU Yuan, LIU ZhiYuan, WU HongHui & Lü ZhaoPing State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，3： | 6 |
| 11 | Extended multiscale finite element method for mechanical analysis of heterogeneous materials显示文摘An extended multiscale finite element method (EMsFEM) is developed for solving the mechanical problems of heterogeneous materials in elasticity.The underlying idea of the method is to construct numerically the multiscale base functions to capture the small-scale features of the coarse elements in the multiscale finite element analysis.On the basis of our existing work for periodic truss materials, the construction methods of the base functions for continuum heterogeneous materials are systematically introduced. Numerical experiments show that the choice of boundary conditions for the construction of the base functions has a big influence on the accuracy of the multiscale solutions, thus,different kinds of boundary conditions are proposed. The efficiency and accuracy of the developed method are validated and the results with different boundary conditions are verified through extensive numerical examples with both periodic and random heterogeneous micro-structures.Also, a consistency test of the method is performed numerically. The results show that the EMsFEM can effectively obtain the macro response of the heterogeneous structures as well as the response in micro-scale,especially under the periodic boundary conditions. | Hong-Wu Zhang·Jing-Kai Wu·Jun L·Zhen-Dong Fu State Key Laboratory of Structural Analysis for Industrial Equipment, Department of Engineering Mechanics, Faculty of Vehicle Engineering and Mechanics, Dalian University of Technology,Dalian 116024,China | 2010 | Acta Mechanica Sinica2010，26，6： | 5 |
| 12 | The effectiveness assessment of gas accumulation processes in Kuqa depression,Tarim Basin,Northwest China显示文摘The effectiveness of gas accumulation processes is controlled by several main geological factors in-cluding charging force,features of gas conduit,sealing properties of caprock,etc. Based on the analysis and statistics of the large-medium size gas accumulations in China,the main parameters,in-cluding the excess pressure difference between the source rock and reservoir bed,the area coefficient of the gas conduit,and the thickness or displacement pressure of caprock,and the criteria for the as-sessment of gas accumulation processes have been established. Using the parameters and the criteria above,the effectiveness of gas accumulation processes in the Kuqa depression was quantitatively evaluated. By integrating the parameters of the excess pressure difference between the source rock and reservoir bed,the area coefficient of fault conduit system,and the caprock thickness in gas charging period,a comprehensive assessment of the effectiveness of gas accumulation in the Kuqa depression has been made. The result reveals that the Tubei-Dawan area,the Central Kelasu area and the Dongqiu-Dina area are three highly-effective areas for gas accumulation in the Kuqa depression. | LIU GuangDi1,SUN MingLiang1,L YanFang2 & SUN YongHe2 1 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 2 Daqing Institute of Petroleum,Daqing 163318,China | 2008 | Science China Earth Sciences2008，51，S2： | 4 |
| 13 | Algorithm of simulation time synchronization over large-scale nodes显示文摘In distributed simulation,there is no uniform physical clock. And delay cannot be estimated because of jitter. So simulation time synchronization is essential for the event consistency among nodes. This paper investigates time synchronization algorithms over large-scale distributed nodes,analyzes LBTS(lower bound time stamp) computation model described in IEEE HLA standard,and then presents a grouped LBTS model. In fact,there is a default premise for existing algorithms that control packets must be delivered via reliable transportation. Although,a theorem of time synchronization message's reliability is proposed,which proves that only those control messages that constrain time advance need reliability. It breaks out the default premise for reliability. Then multicast is introduced into the transmission of control messages,and algorithm MCTS(multi-node coordination time synchronization) is proposed based on multicast. MCTS not only promotes the time advance efficiency,but also reduces the occupied network bandwidth. Experiment results demonstrate that the algorithm is better than others in both time advance speed and occupied network bandwidth. Its time advance speed is about 50 times per second when there are 1000 nodes,approximately equal to that of similar systems when there are 100 nodes. | ZHAO QinPing1,2,ZHOU Zhong1,2 & Lü Fang1,2 1 State Key Laboratory of Virtual Reality Technology and Systems,Beihang University,Beijing 100083,China 2 School of Computer Science and Engineering,Beihang University,Beijing 100083,China | 2008 | Science in China(Series F)2008，51，9： | 4 |
| 14 | Detection of protein microarrays by oblique-incidence reflectivity difference technique显示文摘Biological microarrays with different proteins and different protein concentrations are detected without external labeling by an oblique-incidence reflectivity difference (OIRD) technique. The initial experiment results reveal that the intensities of OIRD signals can distinguish the different proteins and concentrations of protein. The OIRD technique promises feasible applications to life sciences for label-free and high-throughput detection. | WEN Juan1,LU Heng1,WANG Xu1,YUAN Kun1,L HuiBin1,ZHOU YueLiang1,JIN KuiJuan1,YANG GuoZhen1,LI Wei2 & RUAN KangCheng2 1 Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China 2 Key Laboratory of Proteomics,Institute of Biochemistry and Cell Biology,Shanghai Institute for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，2： | 4 |
| 15 | A mechanism for enhanced photocatalytic activity of nano-size silver particle modified titanium dioxide thin films显示文摘Ag-TiO2 nanostructured thin films with silver volume fraction of 0–20% were deposited on silicon and quartz substrates by RF magnetron sputtering and annealed in ambient air at 950°C for 1 h. The phase structure and surface topography of the films were characterized by X-ray diffractometer and transmission electron microscope. Photocatalytic activity of the films was evaluated by light induced degradation of methyl orange (C14H14N3NaO3S) solution using a high pressure mercury lamp as lamp-house. The relation of photocatalytic activity and silver content was studied in detail. It was found that silver content influences phase structure of TiO2 thin films, and silver in the films is metallic Ag (Ag0). With increasing silver content from 0 to 20 vol%, photocatalytic activity of the films increases first and then decreases. A suitable amount (2.5–5 vol%) silver addition can significantly enhance the photocatalytic activity of TiO2 films. The enhanced photocatalytic activity was mainly attributed to the extension of visible light absorption region of the films, the presence of anatase phase, the increase of oxy-gen anion radicals O2? and reactive center of surface Ti3+, and the better separation between electrons and holes on the films surface. | MENG FanMing1,2,3*, LU Fei1,3, SUN ZhaoQi1,3 & Lü JianGuo1,2,4 1 School of Physics and Materials Science, Anhui University, Hefei 230039, China 2 Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China 3 Anhui Key Laboratory of Information Materials and Devices, Anhui University, Hefei 230039, China 4 Department of Physics and Electronic Engineering, Hefei Normal University, Hefei 230061, China | 2010 | Science China(Technological Sciences)2010，53，11： | 4 |
| 16 | Design and analysis of a wideband photonic crystal waveguide with low group-velocity and low dispersion显示文摘The slow light propagation in a line waveguide in the two-dimensional triangular photonic crystal has been numerically studied, based on which a wideband photonic crystal waveguide with low group-velocity and low dispersion is proposed. The numerical simulation analysis shows that it is possible to maximize the group index and minimize the group-velocity dispersion in wide bandwidth by increasing the radius of the basic air hole and changing the position of the first two rows of air holes in photonic crystal waveguides. Such a photonic crystal waveguide exhibits low group velocity and low group-velocity dispersion over a broad wavelength range. A larger group index-bandwidth product is achieved in this type of waveguide structure. The numerically computed results present the normalized bandwidth as 0.32%, 0.48% and 0.642% corresponding to the group index of 85, 58 and 45, respectively. | Lü ShuYuan, ZHAO JianLin & ZHANG Dong Institute of Optical Information Science and Technology, Shanxi Key Laboratory of Optical Information Technology, School of Science, Northwestern Polytechnical University, Xi’an 710072, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，3： | 4 |
| 17 | Correlation between liquid structure and glass forming ability in glassy Ag-based binary alloys显示文摘The atomic structures of liquid Ag-based binary alloys have been investigated in the solidification process by means of X-ray diffraction. The results of liquid structure show that there is a break point in the mean nearest neighbor distance r1 and the coordination number Nmin for glass-forming liquid, while the correlation radius rc and the coordination number Nmin display a monotone variational trend above the break point. It means glass-forming liquids have a steady changing in structure above liquidus and more inhomogeneous state at liquidus. We conclude that there is a strong correlation between liquid structure and glass forming ability in Ag-based binary alloys. | Lü XiaoQian, BIAN XiuFang, XIANG Nan & JIA Ran Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong University, Jinan 250061, China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，3： | 2 |
| 18 | Microstructure and mechanical properties of B_4C-TiB_2-Al composites fabricated by vacuum infiltration显示文摘B4C-TiB2-Al composites were fabricated by infiltrating aluminum into porous B4C-TiB2 preforms in vacuum. The microstucture and mechanical properties of the B4C-TiB2-Al composites were investigated. The hardness decreased, the flexural strength increased, and the fracture toughness first increased and then decreased slightly with an increase in TiB2 content. The B4C-TiB2-Al composite with 40wt.% TiB2 showed the optimized properties. The infiltrated aluminum addition was the leading reason for the fracture toughness improvement of the composites. The tear ridges and dimples on the fracture surface of the composites increased gradually with the increase of infiltrated aluminum content showing inter/transgranular fracture mode. The relationships between the microstructures and the mechanical properties of the composites were discussed. | Lü Peng, YUE Xinyan, RU Hongqiang, and YU Liang Key Laboratory of the Ministry of Education for Anisotropy and Texture of Materials, Northeastern University, Shenyang 110004, China | 2010 | Rare Metals2010，29，1： | 2 |
| 19 | Effects of the activities of key enzymes involved in starch biosynthesis on the fine structure of amylopectin in developing rice (Oryza sativa L.) endosperms显示文摘The dynamic changes of the activities of enzymes involving in starch biosynthesis, including ADP-glucose pyrophosphorylase (AGPase), soluble starch synthases (SSS), starch branching enzyme (SBE) and starch debranching enzymes (DBE) were studied, and changes of fine structure of amy- lopectin were characterized by isoamylase treatment during rice grain development, using trans anti-waxy gene rice plants. The relationships between the activities of those key enzymes were also analyzed. The amylose synthesis was significantly inhibited in transgenic Wanjing 9522, but the total starch content and final grain weight were less affected as compared with those of non-transgenic Wanjing 9522 rice cultivar. Analyses on the changes of activities of enzymes involving in starch bio- synthesis showed that different enzyme activities were expressed differently during rice endosperm development. Soluble starch synthase is relatively highly expressed in earlier stage of endosperm de- velopment, whilst maximal expression of granule-bound starch synthase (GBSS) occurred in mid-stage of endosperm development. No obvious differences in changes of the activities of AGPase and SBE between two rice cultivars investigated, except the DBEs. Distribution patterns of branches of amy- lopectin changed continually during the development of rice grains and varied between two rice culti- vars. It was suggested that amylopectin synthesis be prior to the synthesis of amylose and different enzymes have different roles in controlling syntheses of branches of amylopectin. | Lü Bing, GUO ZhiGang & LIANG JianSheng College of Bioscience and Biotechnology, Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou Univer- sity, Yangzhou 225009, China | 2008 | Science China(Life Sciences)2008，51，10： | 2 |
| 20 | Impact of copy number of distinct SV40PolyA segments on expression of a GFP reporter gene显示文摘The presence of Alu repeats downregulates the expression of the green fluorescent protein(GFP) gene.We found that SV40PolyA(PolyA,240 bp),in either orientation,eliminated the inhibition of GFP gene expression induced by Alu repeats when it was placed between the GFP gene and the Alu repeats.In this study,4 different segments(each 60 bp) were amplified from antisense PolyA(PolyAas) by PCR,and inserted upstream of Alu14 in pAlu14 plasmid(14 Alu repeats inserted downstream of the GFP gene in vector pEGFP-C1 in a head-tail tandem manner).Segments 1F1R(the first 60 bp segment at the 5' end of PolyAas) and 4F4R(the fourth 60 bp segment from the 5' end of PolyAas) did not activate GFP gene expression,whereas 2F2R and 3F3R(the middle two segments) did(as detected by Northern blot analysis and fluorescent microscopy).Different copy numbers of 2F2R and 3F3R segments,in a head and tail tandem manner,were inserted downstream of the GFP gene in pAlu14.p2F2R*4-Alu28,p3F3R*4-Alu18 and p3F3R*4-Alu28 were used as length controls to verify that the decrease in the expression of GFP was not due to the increased length of the inserted segment in the expression vectors.We found that 2 and 4 copies of 2F2R or 3F3R activated the GFP gene more strongly than one copy of them.However,more than 8 copies of 2F2R or 3F3R reduced the activation of the GFP gene.We concluded that SV40PolyAas contained at least two gene-activating elements(2F2R and 3F3R) and 2-4 copies of 2F2R or 3F3R were optimal for the expression of the GFP gene. | YIN Kang,WANG XiuFang,MA Huan,XIE Ying,FENG JingJing,YANG QinQing & Lü ZhanJun Hebei Key Lab of Laboratory Animal,Department of Genetics,Hebei Medical University,Shijiazhuang 050017,China | 2010 | Science China(Life Sciences)2010，53，5： | 2 |
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