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Effect of ambient oxygen pressure on structural, optical and electrical properties of SnO_2.thin films

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Rare Metals 2006年第6期25卷 693-696页

作者： ZHAO Songqing ZHOU Yueliang WANG Shufang ZHAO Kun HAN Peng Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China department of Mathematics and Physics China University of Petroleum Beijing 102249 China

PolycrystaUine SnO2.thin films were deposited on sapphire substrates at 450℃ under different ambient oxygen pressures by pulsed laser deposition technique. The effect of ambient oxygen pressure on the structural, optical and electrical properties of SnO2.thin films was studied. X-my diffraction and Hall measurements show that increasing the ambient oxygen pressure can improve crystallization of the films and decrease resistivity of the films. A violet emission peak centered at 409 nm was observed from photoluminescence measurements for SnO2.films under deposition ambient oxygen pressure above 5 Pa, which is related to the improvement of crystalline of the films.

关键词： tin oxide pulsed laser deposition oxygen pressure PLD resistivity

Effect of annealing on composition,structure and electrical properties of Au layers grown on different thickness Cr layers

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Journal of university of Science and Technology Beijing 2004年第3期11卷 235-239页

作者： Yan Huang Hong Qiu Liqing Pan Yue Tian Fengping Wang Ping Wu department of Physics, Applied Science School, university of Science and Technology Beijing, Beijing {2. china Dept. of Phys. Appl. Sci. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

110 nm-thick Au layers were sputter-deposited on unheated glasses coatedabout a 10 nm-thick and a 50 nm-thick Cr layer respectively. The Au/Cr bilayer films were annealedin a vacuum of 1 mPa at 300℃ for 2. 5 and 30 min, respectively. Auger electron spectroscopy, X-raydiffraction and Field emission scanning electron microscopy were used to analyze the composition andstructure of the Au layers. The resistivity of the bilayer films was measured by using four-pointprobe technique. The adhesion of the bilayer films to the substrate was tested using tape tests. Theamount of Cr atoms diffusing into the Au layer increases with increasing the annealing time,resulting in a decrease in lattice constant and an increase in resistivity of the Au layer. Thecontent of Cr inside the Au layer grown on the thinner Cr layer is less than that grown on thethicker Cr layer. For the Au/Cr bilayer films, the lower resistivity and the good adhesion to theglass substrate can be obtained at a shorter annealing time for a thinner Cr layer.

关键词： Au/Cr bilayer film Cr layer thickness annealing characteristic

Spatial variations of tidal water level and their impact on the exposure patterns of tidal land on the central Jiangsu coast

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Acta Oceanologica Sinica 2010年第1期29卷 79-87页

作者： WANG Zhenyan GAO Shu HUANG Haijun Key Laboratory of Marine geology and Environment Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China MOE Key Laboratory for Coast and Island Development Nanjing University Nanjing 210093China

The exposed area of intertidal zone varies with tidal water level changes, If intercomparisons of satellite images are adopted as a method to determine geomorphological changes of the intertidal zone in response to accretion or erosion processes, then the effect of water level variations must be evaluated. In this study, two Landsat TM images overpassing the central Jiangsu coastal waters on 2.January and 7 March 2.02. respectively, were treated by the changing detection analysis using Image Differencing and Post-classification Comparison. The simultaneous tide level data from four tide gauge stations along the coast were used for displaying the spatial variations of water levels and determining the elevations of waterlines. The results show that the spatial variations of water levels are highly significant in the central Jiangsu coastal waters. The huge differences of tidal land exposure patterns between the two imaging times are related mainly to the spatial variations of tidal water levels, which are controlled by the differences in tidal phases for different imaging times and the spatial variations of water level over the study area at each imaging time. Under complex tidal conditions, e.g., those of the central Jiangsu coastal waters, the tide-surge model should be used to eliminate effectively the effects of water level variations on remote sensing interpretation of geomorphological changes in the intertidal zone.

关键词： waterline water level variations exposure patterns central Jiangsu coast remote sensing

Fabrication of atomically smooth SrRuO_3 thin films by laser molecular beam epitaxy

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Science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 745-749页

作者： LIU GuoZhen1, HE Meng1, JIN KuiJuan1, YANG GuoZhen1, Lü HuiBin1, ZHAO Kun2. ZHENG ShiJian3 & MA XiuLiang3 1 Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, china 2.department of Mathematics and Physics, china university of Petroleum, Beijing 102.49, china 3 Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, china Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China department of Mathematics and Physics China University of Petroleum Beijing China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang China

High-quality SrRuO3 (SRO) thin films and SrTiO3/SRO bilayer were grown epitaxially on SrTiO3 (STO)(001) substrates by laser molecular beam epitaxy. The results of in situ observation of reflection high-energy electron diffraction and ex situ X-ray diffraction θ -2. scan indicate that the SRO thin films have good crystallinity. The measurements of atomic force microscopy and scan tunneling microscopy reveal that the surface of the SRO thin film is atomically smooth. The resistivity of the SRO thin film is 300 μΩ·cm at room temperature. Furthermore, the transmission electron microscopy study shows that the interfaces of STO/SRO and SRO/STO are very clear and no interfacial reaction layer was observed. The experimental results show that the SRO thin film is an excellent electrode material for devices based on perovskite oxide materials.

关键词： SrRuO3 thin film laser molecular beam epitaxy surface morphology

基于GSPN方法的柔性制造系统过程模型和性能分析(英文)

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系统仿真学报 2008年第19期20卷 5258-5261页

作者：马增治王龙山高洪吉林大学机械科学与工程学院长春130025 长春大学机械工程学院长春130022

应用广义随机Petri网方法,对柔性制造系统进行建模和分析,提出了控制策略和优化方法。针对柔性制造系统的离散性,对整个系统的过程模型进行分析。利用广义随机 Petri 网结合马尔可夫链的方法,确立了系统的配置参数,得出了系统的平均运... 详细信息

应用广义随机Petri网方法,对柔性制造系统进行建模和分析,提出了控制策略和优化方法。针对柔性制造系统的离散性,对整个系统的过程模型进行分析。利用广义随机 Petri 网结合马尔可夫链的方法,确立了系统的配置参数,得出了系统的平均运行时间,机床的平均使用率,系统的生产率,故障概率,对系统的优化和生产效率的提高以及柔性的提高提供了理论支持。最后,通过柔性制造系统实例,对该方法进行了检验。

关键词：广义随机Petri 网(GSPN) 柔性制造系统马尔可夫链过程模型

CATHODIC REDUCTION OF METAL-CHLORIDE COORDINATION IONS

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中国有色金属学会会刊：英文版 1994年第1期4卷 39-44页

作者： Zen, Zhenou(department of Applied Chemistry Chemistry,South china {2. of Technology, Guangzhou510641, china)Yang, Songqing(department of Chemistry, Central South {2. of Technology, Changsha 410083, china)

ＣＡＴＨＯＤＩＣＲＥＤＵＣＴＩＯＮＯＦＭＥＴＡＬ－ＣＨＬＯＲＩＤＥＣＯＯＲＤＩＮＡＴＩＯＮＩＯＮＳＺｅｎ，Ｚｈｅｎｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＣｈｅｍｉｓｔｒｙＣｈｅｍｉｓｔｒｙ，ＳｏｕｔｈＣｈｉｎａ... 详细信息

ＣＡＴＨＯＤＩＣＲＥＤＵＣＴＩＯＮＯＦＭＥＴＡＬ－ＣＨＬＯＲＩＤＥＣＯＯＲＤＩＮＡＴＩＯＮＩＯＮＳＺｅｎ，Ｚｈｅｎｏｕ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＣｈｅｍｉｓｔｒｙＣｈｅｍｉｓｔｒｙ，ＳｏｕｔｈＣｈｉｎａＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎ...

关键词： cathodic reduction metal chloride coordination ions copper chloride zinc chlo-ride lead chloride chronopotential method

Analytical Models for the Design of High Strength Steel Tailor Welded Blanks

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Journal of Iron and Steel Research International 2011年第S1期18卷 646-651页

作者： CHEN Shui-sheng 1,LIN Jian-ping 1,LIU Jing 1,WANG Bin 2.(1.School of Mechanical Engineering,Tongji university,Shanghai 2.1804,china 2.SAIC Motor Corporation Limited,Shanghai 2.1804,china) Tongji Univ Sch Mech Engn Shanghai 201804 Peoples R China SAIC Motor Corp Ltd Shanghai 201804 Peoples R China

To further reduce the weight of tailor-welded blanks (TWBs) parts,the thicker material of conventional TWBs were replaced by high-strength steel (HSS).However,designers need to determine the thickness of HSS sheet by trial and error,without theoretical *** this paper,analytical models were developed to predict the thickness or the mechanical parameters of HSS *** the case of limit dome height (LDH) tests,simulations and experiments were performed to verify the accuracy of the proposed models in terms of LDH and weld line *** to numerical and experimental results demonstrates the accuracy of the *** analytical models can predict the mechanical characteristics or the thickness of HSS sheet used in place of the thicker side of TWBs,which provide designers a valuable tool to design HSS TWBs.

关键词： high-strength steel tailor-welded blanks prediction model synthetic strength

Identification and Analysis of Genes Present in Leptospira interrogans serovar lai but Absent in L. biflexa serovar monvalerio

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 832-839页

作者： Ping HE, Xiang-Yan ZHANG, Xiao-Kui GUO*, Bao-Yu HU, Xiao-Tian HUANG, Yang YANG, and Guo-Ping ZHAO1,2. department of Microbiology and Parasitology, Shanghai Second Medical university, Shanghai 2.002., {2. 1 Research Center of Biotechnology, Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 2.0031, {2. 2.hinese National Human Genome Center at Shanghai, Zhangjiang High Tech Park, Shanghai 2.12.3, {2. department of Microbiology and Parasitology Shanghai Second Medical UniversityShanghai 200025 China Research Center of Biotechnology Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China Chinese National Human Genome Center at ShanghaiZhangjiang High Tech Park Shanghai 201203 China

Genes present in virulent bacterial strains but absent in avirulent close relatives can be of great biologic and clinical interest. This project aimed to identify strain specific DNA sequences of Leptospira interrogans serovar lai, which is absent in the saprophytic L. biflexa serovar monvalerio, via suppression subtractive hybridization with the former as the tester while the latter as the driver. The mixture of PCR amplified DNA fragments from two subtractive hybridization experiments were cloned into pMD18-T vector and the positive clones were identified by dot blotting against the chromosome DNA of the two strains individually. After DNA sequencing and analysis, the distribution of these genomic fragment sequences in a panel of pathogenic and nonpathogenic leptospires was investigated employing dot blot analysis. Among the 188 positive clones randomly chosen, 2. contained the tester strain specific genomic regions, of which, 5 were non-coding fragments while the others contained 2. distinct protein coding sequences. Besides 9 genes encoding functional proteins, 12.genes encode unknown proteins and the rest two genes encode proteins with recognizable domain structures, one for a putative leucine-rich repeats (LRR) family protein while the other as an outer-membrane protein. Our experiment results indicated that suppression subtractive hybridiza- tion is effective for screening specific DNA sequences between two leptospiral strains, and some of these sequences might be responsible for virulence determination. Further analysis of these DNA sequences will provide important information on the pathogenesis of Leptospira.

关键词： Leptospira interrogans serovar lai suppression subtractive hybridization (SSH) specific genes

Simulation of three-dimensional cohesive sediment transport in Hangzhou Bay,china

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Acta Oceanologica Sinica 2010年第2期29卷 98-106页

作者： DU Panjun DING Pingxing HU Kelin State Key of Estuarine and Coastal Research East China Normal University Shanghai 200062 China Forecast Centers for East china Sea State Oceanic Administration Shanghai 200062 China

Sediment transport in the Hangzhou Bay is extremely complicated due to its bathymetry and hydrodynamic conditions. The ECOMSED model is employed to simulate three-dimensional （3-D） cohesive sediment transport in Hangzhou Bay. Dynamical factors such as Coriolis force, tides, salinity, river discharges, and waves are considered in the model. The wave parameters, including the significant wave height, period, and direction, are calculated with the SWAN model. The Grant-Madsen model is introduced for the bed shear stress due to the combined effect of waves and currents. The formulation of bed shear stress used to calculate the sink/source terms is modified based on previous research that sufficiently validated the formulation with measurement data. The integrated model of the above-mentioned models is applied to simulate sediment transport in Hangzhou Bay. The results of the simulation agree well with field observations concerning the distribution of suspended sediment, indicating that the sediments are remarkably suspended in Hangzhou Bay under the action of waves and currents.

关键词： waves currents suspended sediment deposition erosion Grant-Madsen Model