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| 1 | Geospatial-temporal analysis of land-use changes in the Yellow River Delta during the last 40 years显示文摘Comprehensive study on land-use change of spatial pattern and temporal process is the key component in land use/land cover changes (LUCC) study nowadays. According to the theories and methods of Geo-information Tupu (Carto-methodology in Geo-information, CMGI) for geospatial and temporal analysis and integration models of spatial pattern and temporal processes in GIS, the paper puts forward Tupu methodology of land-use change and names the basic synthetic unit of spatial-temporal information Tupu unit. Tupu unit is the synthetic unit for geospatial-temporal analysis, which is synthesized by “space·attribute·process”features and composed of relatively homogeneous geographic unit and temporal unit. Based on the spatial features of 4 stages of land-use change in 1956, 1984, 1991, and 1996, a series of Tupu on land-use change in the Yellow River Delta (YRD) are created and studied in the paper, which includes 3 temporal units of spatial-temporal Tupu, process Tupu of land-use changes during the last 40 years, and reconstructions of a series of “arisen”Tupu, “arisen”process Tupu and pattern Tupu on land-use changes in the last 40 years by remapping tables of a reclassifying system. There are 3 methods of Tupu analysis on land-use change that are used to disclose change processes of land-use spatial conversion in YRD, such as spatial query and statistics, order of Tupu units by area and land-use conversion matrixes. In order to reveal the spatial pattern of land-use change processes, we analyze spatial-temporal changes of each Tupu above in various temporal units and spatial difference of pattern Tupu in the last 40 years by dynamic Tupu units. Tupu analysis on regional land-use is a promising trial on the comprehensive research of “spatial pattern of dynamic process”and “temporal process of spatial pattern”in LUCC research. The geo-information Tupu methodology would be a powerful and efficient tool on integrated studies of spatial pattern and temporal process in geoscience. | YE Qinghua1,3,4,LIU Gaohuan2,TIAN Guoliang1,CHEN Shenliang3,HUANG Chong2,CHEN Shupeng1,2,LIU Qingshen2,CHANG Jun2 & SHI Yanan2 1.State Key Laboratory of Remote Sensing Science,Institute of Remote Sensing Applications(IRSA),Chinese Academy of Science(CAS),Beijing 100101,China 2.Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China 3.State Key Laboratory of Estuarine and Coastal Research,East China Normal University,Shanghai 200062,China 4.Institute of Tibetan Plateau Research(ITPR),CAS,Beijing 100085,China Correspondence should be addressed to Ye Qinghua(email: yeqh@itpcas.ac.cn) | 2004 | Science China Earth Sciences2004，47，11： | 22 |
| 2 | Ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang显示文摘The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, China, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 40 years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 40 years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 40 years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2) the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3) the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage. | CHEN Xi1, LUO Geping1, XIA Jun2, ZHOU Kefa1, LOU Shaoping3 & YE Minquan4 1. Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China 2. Institute of Geographical and Resources Sciences, Chinese Academy of Sciences, Beijing 100101, China 3. Urumqi Meteorological-satellite Land Station, Urumqi 830011, China 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 830011, China Correspondence should be addressed to Chen Xi | 2005 | Science China Earth Sciences2005，48，6： | 19 |
| 3 | Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅰ:Theoretical Formulation显示文摘Ball bearings play an important role in various rotating machineries,but the complicated kinematic and tribological features of ball bearings make many aspects of their operating behaviors still inconclusive.Most theoretical analyses of ball bearings up to date are based on either the hypothesis of race control or other empirical models to determine the ball motion of ball bearings,but none of these strategies can reveal and consequently employ the intrinsic coupling mechanism between the spin and the tangential traction of contacting bodies rolling upon one another.To remedy the deficiency of current analytical models for ball bearing analysis,the rolling contact theory is employed to establish an explicit link between motions and interactions within ball bearings.A differential slip model is established to precisely define the slip component due to the significant curvature of the common contact patches between the ball and inner/outer raceways.The creepage and the spin ratio are formulated to accurately define the relative rigid motion between the ball and the inner/outer raceway.Then a quasi-static analytical model is established that can accurately determine the motions of the balls and races of the ball bearing.It can also give a vivid description of the slip and traction distributions within the contact area.The analytical model can be effectively used to analyze the operational conditions and tribological features of solid-lubricated ball bearings.It can also be used optimize the construction of ball bearings for specific applications. | CHEN Wenhua1,2,MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2 1 Institute of Mechanical Design,Zhejiang University,Hangzhou 310027,China 2 Institute of Mechanical Design and Manufacturing,Zhejiang Sci-Tech University,Hangzhou 310018,China 3 State Testing Laboratory of Hangzhou Bearing Test & Research Center,Hangzhou 310022,China | 2012 | Chinese Journal of Mechanical Engineering2012，25，1： | 16 |
| 4 | Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions显示文摘The soil infiltrability of hill-slope is important to such studies and practices as hydrological process, crop water supply, irrigation practices, and soil erosion. A new method for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-out was advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimated from the advances of runoff on soil surface and the water running out of the slope were derived. Experiments of 2 cases were con-ducted. Case I was done under a rainfall intensity of 20 mm/h, at a slope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case II was under a rainfall intensity of 60 mm/h and a slope of 20° with a runoff/on length (area) ratio of 1 : 1. Double ring method was also used to measure the infiltrability for comparison purposes. The experiments were done with soil moisture of 10%. Required data were collected from laboratory experiments. The infiltrability curves were computed from the experimental data. The results indicate that the method can well conceptually represent the transient infiltrability process, with capability to simulate the very high initial soil infiltrability. The rationalities of the method and the models were validated. The errors of the method for the two cases were 1.82%/1.39% and 4.49%/3.529% (Experimental/Model) respectively, as estimated by comparing the rainfall amount with the infiltrated volume, to demonstrate the accuracy of the method. The transient and steady infiltrability measured with double ring was much lower than those with this new method, due to water supply limit and soil aggregates breaking down at initial infiltration stage. The method can overcome the short backs of the traditional sprinkler method and double ring method for soil infil-traility. It can be used to measure the infiltrability of sloped surface under rainfall-runoff-erosion condi-tions, in the related studies. | LEI Tingwu1,2, LIU Han1, PAN Yinghua3, ZHAO Jun2, ZHAO Shiwei2 & YANG Yonghui2 1. The Key Laboratory of Modern Precision Agriculture System Integration Research, College of Hydraulic and Civil Engineer-ing, China Agricultural University, Beijing 100083, China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Yangling 712100, China 3. Geographic and Resources Management College, Yantai Normal University, Yantai 264025, China | 2006 | Science China Earth Sciences2006，49，2： | 11 |
| 5 | Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery显示文摘Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxybutyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a coreshell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery. | CHENG Jing1 & WANG Jun2 1 Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei 230026, China 2 Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China | 2009 | Science China Chemistry2009，52，7： | 10 |
| 6 | AtMYB103 is a crucial regulator of several pathways affecting Arabidopsis anther development显示文摘Previous reports indicated that AtMYB103 has an important role in tapetum development,callose dissolution,and exine formation in A.thaliana anthers.Here,we further characterized its function in anther development by expression pattern analysis,transmission electron microscopy observation of the knockout mutant,and microarray analysis of downstream genes.A total of 818 genes differentially expressed between ms188 and the wild-type were identified by global expression profiling analysis.Functional classification showed that loss-of-function of AtMYB103 impairs cell wall modification,lipid metabolic pathways,and signal transduction throughout anther development.RNA in situ hybridization confirmed that transcription factors acting downstream of AtMYB103 (At1g06280 and At1g02040) were expressed in the tapetum and microspores at later stages,suggesting that they might have important roles in microsporogenesis.These results indicated that AtMYB103 is a crucial regulator of Arabidopsis anther development. | ZHU Jun1,ZHANG GuoQiang2,CHANG YuHua2,LI XiaoChuan2,YANG Jun2,HUANG XueYong2,YU QingBo2,CHEN Hui3,WU TianLong1* & YANG ZhongNan2* 1College of Agriculture and Biotechnology,Shanghai Jiao Tong University,Shanghai 200240,China 2College of Life and Environmental Sciences,Shanghai Normal University,Shanghai 200234,China 3Shanghai Institute of Plant Physiology and Ecology,Chinese Academy of Sciences,Shanghai 200032,China | 2010 | Science China(Life Sciences)2010，53，9： | 10 |
| 7 | Repair effect of diabetic ulcers with recombinant human epidermal growth factor loaded by sustained-release microspheres显示文摘In this study the w/o/w extraction–evaporation technique was adopted to prepare poly(lactic-co-glycolic acid) (PLGA) microspheres loading recombinant human epidermal growth factor (rhEGF). The micro-spheres were characterized for morphology by transmission electron microscopy (TEM) and particle size distribution. The release performances, the proliferation effects and therapeutic effects of rhEGF-loaded PLGA microspheres were all studied. The results showed that these spherical micro-spheres had a narrow size distribution and a high drug encapsulation efficiency (85.6%). RhEGF-loaded microspheres enhanced the growth rate of fibroblasts and wound healing more efficiently than pure rhEGF. The number of the proliferating cell nuclear antigen (PCNA) in the epidermis layer with the mi-crosphere treatment was significantly larger than those of the control groups. Overall locally sustained delivery of rhEGF from biodegradable PLGA microspheres may serve as a novel therapeutic strategy for diabetic ulcer repair. | DONG XiaoQing1, XU Jun2, WANG WeiCai1, Luo Hao1, LIANG XiaoFei1, Zhang Lei1, Wang HanJie1, Wang PengHua2 & CHANG Jin1 1 Institute of Nanobiotechnology, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China 2 Department of Diabetic Foot, Tianjin Medical University Metabolic Disease Hospital, Tianjin 300070, China | 2008 | Science China(Life Sciences)2008，51，11： | 7 |
| 8 | DNA barcoding provides distinction between Radix Astragali and its adulterants显示文摘Based on variable nuclear and/or organellar DNA sequences among vastly divergent species as well as morphologically indistinguishable species, DNA barcoding is widely applicable in species identification, biodiversity studies, forensic analyses, and authentication of medicinal plants. The roots of Astragalus membranaceus and A. membranaceus var. mongholica are commonly used as Radix Astragali in several Asian countries, including China, Japan, and Korea. However, in addition to the two species recorded in the Chinese Pharmacopoeia, there are twenty-three species from different genera including Astragalus, Oxytropis, Hedysarum, and Glycyrrhiza, which have been used as adulterants not only in trading markets but also by the herbal medicine industry. Therefore, a simple, reliable, and accurate classification method is important for distinguishing authentic Radix Astragali from its adulterants. In this study, we acquired data for 37 samples from four related genera within the family Fabaceae. Then we compared four candidate DNA barcoding markers using ITS, matK, rbcL, and coxI sequences from nuclear, chloroplast, and mitochondrial genomes, all commonly used for plants to identify genetic variations among genera, intraspecies, and interspecies. We observed higher divergences among genera and interspecies for ITS, which have the average Kimura 2-parameter distances of 4.5% and 14.1%, respectively, whereas matK was found to have sufficient divergence at the intraspecific level. Moreover, two indels detected in the matK sequence are useful for PCR studies in distinguishing Radix Astragali from its adulterants. This study suggests that the combined barcoding regions of ITS and matK are superior barcodes for Radix Astragali and further studies should focus on evaluating the applicability and accuracy of such combined markers for a wide range of traditional Chinese herbs. | GUO HaiYan1,2, WANG WeiWei2, YANG Ning2, GUO BaoLin3, ZHANG Sun2, YANG RuiJing2, YUAN Ye2, YU JunLin4, HU SongNian2, SUN QiShi1 & YU Jun2 1School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang 110016, China 2Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 101300, China 3Chinese Academy of Medical Sciences, Peking Union Medical College Institute of Medicinal Plant Development, Beijing 100094, China 4Department of Chemistry, Tonghua Normal College, Tonghua 134002, China | 2010 | Science China(Life Sciences)2010，53，8： | 7 |
| 9 | A preliminary study on dead geostationary satellite removal显示文摘The collision between satellites IRIDIUM 33 and COSMOS 2251 indicated that the clash of two on-orbit satellites was becoming an inevitable reality. Our calculation with the two-line orbit element by NORAD showed that some two geostationary satellites had approached very close in July 2009. Therefore, more attention should be given to avoid such collisions. This paper analyzes the orbital long-term variation of a dead satellite drifting in the geostationary orbit. Also, the negative effects posed by dead satellites upon the on-orbit operational geostationary satellites are studied. Then the paper proposes a novel idea to launch a satellite sweeper whose purpose is to collect the on-orbit dead satellites and help them de-orbit to a 'graveyard'. The satellite sweeper consists of a parent satellite and a child satellite. The child satellite collects a dead satellite and transfers it to a higher orbit. The parent satellite stationed in the geostationary orbit is in charge of refueling the child satellite. The strategy of maneuver and rendezvous is presented and a series of formulas are derived. The analysis results show that our method to clean the geostationary orbital zone is practical and fuel-saving. With the help of just a few satellite sweepers, we can gain a clean environment of geostationary orbit environment again. | LI YuHeng1, YANG KaiZhong2, SHAN ChengSheng2, LUO Dan2, GUAN Hui2, ZHENG Jun2, CHENG Hong2 & MAN Li2 1 Xidian University, Shaanxi 710071, China 2 Xi’an Satellite Control Center, Shaanxi 710043, China | 2010 | Science China(Technological Sciences)2010，53，12： | 7 |
| 10 | Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings Part Ⅱ:Results and Discussion显示文摘Ball bearings are widely employed mechanical components characterized by high precision and quality,and usually play important roles in various rotary machines and mechanisms.Many advanced applications require a deep understanding of their various kinematic and tribological characteristics that are essential to predict the fatigue endurance,relieve the vibration and minimize the power dissipation of ball bearings in particular applications.An angular contact ball bearing under a specified operating condition is simulated with the quasi-static/creepage analytical model proposed in the preceding article.The results demonstrate that the ball bearing is a statically determinate system.That the balls spin on both inner and outer races means the ball is controlled by neither the inner nor the outer raceway.The friction between the ball and raceway renders the inner and outer contact angles unequal.The larger the coefficient of friction is,the larger the angle deviation.The tangential traction perpendicular to the rolling direction due to the spin induces a gyro-like rotation of the ball with respect to the raceway even if no inertial effects are considered.The tangential elastic compliance of contacting surfaces gives rise to locked areas within the contact patch and transforms the sliding lines from circles into spirals.The differential slip due to the close conformity of the ball and raceway makes the sliding and traction distributions asymmetric,which will influence the location of the spinning center of the ball with respect to the raceway.The quasi-static/creepage model can be used to reveal the operating behaviors of ball bearings running under steady conditions and to optimize the design of ball bearings for specific applications. | CHEN Wenhua1,2,MA Zikui1,GAO Liang1,LI Xinglin3,and PAN Jun2 1 Institute of Mechanical Design,Zhejiang University,Hangzhou 310027,China 2 Institute of Mechanical Design and Manufacturing,Zhejiang Sci-Tech University,Hangzhou 310018,China 3 State Testing Laboratory of Hangzhou Bearing Test & Research Center,Hangzhou 310022,China | 2012 | Chinese Journal of Mechanical Engineering2012，25，1： | 7 |
| 11 | Simultaneous Analysis of Thirteen Bioactive Components in Evodia rutaecarpa and Its Varieties by HPLC-DAD-MS显示文摘Objective To control the quality of Evodia rutaecarpa better.Methods An HPLC-DAD-MS/MS method was established for the rapid and efficient identification of bioactive constituents and for simultaneous quantitative analysis of four bioactive ingredients including evodiamine,rutaecarpine,dehydroevodiamine,and evodin in E.rutaecarpa,which was applied to evaluating eight samples of E.rutaecarpa and its varieties from different areas.Results Thirteen potentially bioactive constituents including one flavonoid glycoside,one limonin,four indoloquinazoline alkaloids,and seven quinolone alkaloids were identified in all samples and the contents of dehydroevodiamine,evodine,evodiamine,and rutaecarpine varied widely from 0.10% to 0.51%,0.49% to 3.12%,0.07% to 1.56%,and 0.10% to 0.69%,respectively.Conclusion This method is found to be convenient,fast,accurate,and it is facilitated to improve the quality control standard of E.rutaecarpa and related products. | XU Hai-yu1,3,ZHANG Tie-jun2,XIAO Xue-feng1,ZHAO Ping1,LIU Chang-xiao3,XU Jun2 1.Tianjin University of Traditional Chinese Medicine,Tianjin 300193,China 2.Tianjin Engineering Laboratory of Quality Control Techniques for TCM,Tianjin Institute of Pharmaceutical Research,Tianjin 300193,China 3.The National Laboratory of Pharmacodynamics and Pharmacokinetics,Tianjin Institute of Pharmaceutical Research,Tianjin 300193,China | 2010 | Chinese Herbal Medicines2010，2，2： | 6 |
| 12 | Coupling the hydrological and ecological process to implement the sustainable water resources management in Hanjiang River Basin显示文摘Research on the combination of hydrological variation and ecological demands plays an important role in water availability assessment and sustainable management on basin scale. An integrative frame, consisting of hydrological regime modelling, ecological water demands estimation and renewable resources management, is given in this paper in order to support the implementation of the sustainable water resources management. The suggested integrative frame has been used to study the integrated water resources management in southern Hanjiang River Basin which is the water source of South-toNorth Water Transportation Project in China. SWAT (soil and water assessment tool) model was used to simulate the monthly averaging streamflow and the amounts of ecological water demands in stream were also estimated in order to evaluate the available water resources for the local users and the transportation project. Then we formed the developing scenarioes by coupling the available water resources, the recovering rate of water resources in natural water cycle, the local water use rate and the amounts of the water transported to North, and used the Scheafer model to analyze their evolving trajectories. Eventually, the sustainable water resources management measures were assembled by the comprehensive evaluation of the scenarioes. The research indicates that the integrative frame provided a new way for the integrated water resources management in river basin. | ZHANG Xiang1 & XIA Jun2 1 State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China 2 Key Laboratory of Water Cycle and Related Land Surface Processes, IGSNRR, Chinese Academy of Sciences, Beijing 100101, China | 2009 | Science China(Technological Sciences)2009，52，11： | 6 |
| 13 | Ferroelectric properties of Bi_(3.25)La_(0.75)Ti_(3)O_(12) thin films prepared by sol-gel method显示文摘The Bi3.25La0.75Ti3O12 thin films were fabricated on the Pt/Ti/SiO2/Si substrates using sol-gel method. The structure and morphology of the films were characterized us-ing X-ray diffraction and atomic force microscopy. The thin films showed a perov- skite phase and dense microstructure. The 2Pr and 2Vc of the Bi3.25La0.75Ti3O12 thin films annealed at 700℃ were 18.6 μC/cm2 and 4.1 V, respectively, under an applied voltage 10 V. After the switching of 1×1010 cycles, the Pr value decreased to 90% of its pre-fatigue values. The films showed good insulating behavior according to the test of leakage current. The dielectric constant and the dissipation factor of the Bi3.25La0.75Ti3O12 thin films were about 176 and 0.046 at 1 kHz, respectively. | GUO DongYun1, LI MeiYa1, PEI Ling1, YU BenFang1, WU GengZhu1, ZHAO XingZhong1, WANG YunBo2 & YU Jun2 1 Department of Physics, Wuhan University, Wuhan 430072, China 2 Department of Electronic Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China | 2007 | Science China(Technological Sciences)2007，50，1： | 4 |
| 14 | Pedodiversity: a controversial concept显示文摘The concept of pedodiversity and its measurement methodology proposed and developed by Ibá?ez research term is introduced. An attempt to apply pedodiversity to analyze spatial soil variation and distribution patterns on the global scale is briefly demonstrated. Furthermore, constructive comments and criticisms on pedodiversity and its measurement from the noted pedologists and ecologists are outlined. Finally, potential applications of pedodiversity in soil science and other relevant disciplines are discussed. | CHEN Jie1, ZHANG Xue-lei1, GONG Zi-tong1, WANG Jun2 (1. Institute of Soil Science, CAS, Nanjing 210008, China 2. Surveying and Mapping Bureau of Jiangsu Province, Nanjing 210008, China) | 2001 | Journal of Geographical Sciences2001，11，1： | 4 |
| 15 | Preparation and ferroelectric properties of Bi_(3.4)Ce_(0.6)Ti_3O_(12) thin films grown by sol-gel method显示文摘We have investigated the preparation and properties of Bi3.4Ce0.6Ti3O12 thin films. The Bi3.4Ce0.6Ti3O12 thin films were fabricated on the Pt/Ti/SiO2/Si substrates using sol-gel method. The structure and morphology of the films were characterized us- ing X-ray diffraction and atomic force microscopy. The thin films showed a perovskite phase and dense microstructure. The dielectric constant and the dissi- pation factor of the Bi3.4Ce0.6Ti3O12 thin films were about 172 and 0.031 at 1 kHz, respectively. The 2Pr and 2Ec of the Bi3.4Ce0.6Ti3O12 thin films were 67.1 μC/cm2 and 299.7 kV/cm, respectively, under an applied field of 600 kV/cm. The Bi3.4Ce0.6Ti3O12 film did not show fatigue up to 4.46×109 switching cycles at a frequency of 1 MHz, and showed good insulating behavior according to the test of leakage current. | GUO DongYun1, LI MeiYa1, LIU Jun1, YU BenFang1, PEI Ling1, WANG YunBo2, YU Jun2 & YANG Bin2 1 Department of Physics, Wuhan University, Wuhan 430072, China 2 Department of Electronic Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, China | 2008 | Science China(Technological Sciences)2008，51，1： | 3 |
| 16 | Winter Phytoplankton Assemblages of Coastal Yellow Sea Connected to Jiaozhou Bay,China显示文摘The daily species variation of phytoplankton assemblage of coastal Yellow Sea connected to Jiaozhou Bay in the sea-water around the Xiaoqingdao Island was studied for the three months of winter, 2003. A total of 79 taxa from four phyla, Bacil-lariophyta (52 species), Pyrrophyta (25 species), Chrysophyta (1 species), and Cyanophyta (1species) were determined. In general, the most important groups were Bacillariophyta and Pyrrophyta on cell abundance and species richness. In January, the dominant species was mainly composed of cosmopolitan species such as Skeletonema costatum, then it changed to cosmopolitan species Tha-lassiosira nordenskiodii in February, and finally, it recovered to Skeletonema costatum again in March. Cell abundance ranged from 1.02 to 130.71×103 cells L-1with a single peak on 6th Feb., and the average abundance was 28.11 ± 26.01×103 cells L-1 (n = 90) during the winter time. The trends of Shannon-Weiner diversity index and Pielou’s evenness index were contrary to cell abundance, whereas the species diversity and evenness were the lowest in February. Temperature and salinity were closely correlated to phytoplankton species composition and cell abundance. According to the variations of temperature and salinity, species sequence was obvious at the studied site. This implies that the phytoplankton community of inner Jiaozhou Bay would be influenced heavily by the coastal Yel-low Sea phytoplankton assemblages. | WEN Lixia1), 2), SUN Jun2),*, HE Qing2), WANG Dan2), and WANG Min1) 1) College of Marine Life Science, Ocean University of China, Qingdao 266003, P. R. China 2) Key Laboratory of Marine Ecology & Environmental Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, P. R. China | 2007 | Journal of Ocean University of China2007，6，1： | 3 |
| 17 | A computer simulation of nucleation and growth of thin films显示文摘A three-dimensional kinetic Monte Carlo technique has been developed for simulating the nucleation and growth of thin films. This model involves incident atom attachment, surface diffusion of the atoms on the growing surface and atom detachment from the growing surface. It takes some new effects into account, such as a significant improvement in calculation of activation energy for the atom diffusion, which renders the model more reasonable. In addition three optimum temperatures and the consistency of their dependence on deposition rate have been found out; the dependence of the surface roughness and relative density on the deposition rate has been discussed; and the approximation of freezing neighbour atoms and periodic boundary conditions has been applied. | ZHENG Xiaoping1,ZHANG Peifeng2,HE Deyan2,LIU Jun2& MA Jiantai3 1. Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, Lanzhou 730070, China 2. School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China 3. School of Chemistry and Chemistry Engineering, Lanzhou University, Lanzhou 730000, China | 2004 | Science China(Physics,Mechanics & Astronomy)2004，47，4： | 2 |
| 18 | GENERALIZED FLOW LAWS OF POLYPHASE ROCKS: AN OVERVIEW显示文摘Rheological properties of polyphase rocks play an important role in the dynamics of the lithosphere and asthenosphere. However, such fundamental issues have not been well resolved. A theoretical analysis has been made to develop expressions for the flow laws of polyphase rocks in terms of the volume fractions and flow laws of their constituent phases. The flow strengths predicted by the proposed model for common crustal and upper mantle rocks such as granite, diorite, diabase and lherzolite, and for synthetic two phase composites such as forsterite enstatite and water ice ammonia dehydrate aggregates are in good agreement with previously determined experimental values. The proposed theoretical model allows one to calculate, to the first approximation, the flow laws of a large number of polyphase rocks at geologic conditions based on the experimentally determined flow laws of a relatively small number of monomineralic aggregates. | JI Shao cheng1, FAN Wei ming2 and WANG Yue jun2(1. Department of Civil, Geological and Mining Engineering, Ecole Polytechnique de Montreal, Montreal, Quebec, Canada 2. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China) | 2002 | Geotectonica et Metallogenia2002，26，1： | 2 |
| 19 | Tectonic evolvement of metamorphic complexes at Jilin paleocontinental margin during the transition from late Archaean to early Proterozoic显示文摘The kinematics and dynamical process of tectonic evolvement of metamorphic complexes at the interim from late Archaean to early Proterozoic is one of the key problems in geosciences. For the disputation on the genesis of metamorphic complexes at the margin of Jilin palaeocontinent, this paper takes the example of Banshigou region, Jilin Province to discuss the dynamical evolution of palaeocontinent during the transition from late Archaean to early Pro- terozoic (2600—2000 Ma). On the time sequence, from center to palaeocontinental margin, it shows a series of dynamical movements including underplating, horizontal movement, subduc- tion, intraplate extension and separation. And its corresponding sequence of kinematical modes is as follows: vertical movement, horizontal movement, extension and shearing in contact zone, uplift-sliding movement in paleocontinental margin and interformational sliding, resulting in such tectonite sequence, tectonic gneiss, gneissic complex, gneissic complex-mylonite, mylonite and fracture cleavage-mylonite, which consist of the main body of metamorphic complexes. Their palaeostresses are: < 20, 20.40, 21.72, 28.80 and 30.8-69.8 MPa respectively. The deforma- tional metamorphic temperature is between hornblende and low-grade greenschist facies. The general deformational characters of Jilin palaeocontinent reflect a complete dynamic system of crust evolution, which indicates that the formation of the metamorphic complexes and the tec- tonic evolution are altered from vertical movement to compression to extension. It also indicates a continuous tectonic transformation from deep to shallow, and from ductile to brittle. The trans- formation between different dynamic mechanisms not only forms tectonic rocks, but also benefits the linking up, exchange and enrichment with rock-forming minerals and ore-forming elements. This research is helpful to classifying regional tectonic events and making further study on the evolution of palaeocontinental dynamics. | SUN Zhongshi1,DENG Jun2,JIANG Yanguo3,WANG Jianping2,WANG Qingfei2 & WEI Yanguang2 1.Department of Earth Sciences,Jilin University,Changchun 130061,China 2.Department of Geosciences and Mineral Resources,China University of Geosciences,Beijing 100083,China 3.Weihai Gold Institute,Shandong Weihai Gold Bureau,Weihai 264205,China Correspondence should be addressed to Sun Zhongshi(email: sunzs219@163.com) | 2004 | Science China Earth Sciences2004，47，11： | 2 |
| 20 | Characterization and function analysis of a Halo-alkaline-adaptable Trk K^+ uptake system in Alkalimonas amylolytica strain N10显示文摘By functional complementation of Escherichia coli mutants defective in potassium (K+) uptake, two genes that are required for K+ uptake in halo-alkaliphilic Alkalimonas amylolytica strain N10 were cloned. These two genes, Aa-trkA (1337 bp) and Aa-trkH (1452 bp), were adjacent on the A. amylolytica N10 chromosome and transcribed in opposite directions. Complementation experiments revealed that Aa-TrkA and Aa-TrkH from A. amylolytica strain N10 restored the ability to grow at low K+ concentration in E. coli △trkA and △trkG △trkH strains, respectively. In addition, Aa-TrkAH supported the growth of an E. coli △sapD strain, indicating that the ATP-binding protein TrkE was dispensable for the Trk system of A. amylolytica strain N10. The net K+ uptake was detected at different pH levels and the critical NaCl concentration indicated that Aa-TrkAH is an alkaline-adaptable and partially halo-adaptable K+ transporter. Kinetics determined by heterogeneous K+ transport experiments with an E. coli △trkA strain revealed that Aa-TrkAH has an alkaline pH optimum close to 8.5 or higher. Site-directed mutagenesis of Aa-TrkH showed that Phe103 and Ser229 play certain key roles in K+ selection and transportation. The molecular chaperones groES-groEL and tig promoted Aa-TrkH and Aa-TrkA overexpression in vitro. | GUO YongHao1, XUE YanFen1, LIU Jun2, WANG QuanHui1 & MA YanHe1 1 State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China 2 Department of Pharmacology and Systems Therapeutics, Mount Sinai School of Medicine, New York 10029, USA | 2009 | Science China(Life Sciences)2009，52，10： | 1 |
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