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Preparation of graphitic carbon nitride by electrodeposition

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Chinese Science Bulletin 2003年第16期48卷 1737-1740页

作者： LI Chao1,2. CAO Chuanbao1 & ZHU Hesun1 1. Research center of materials Science, Beijing Institute of Technology, Beijing 100081, {2. 2. Department of Chemical Engineering, Zhengzhou Institute of Light Industry, Zhengzhou 450002.{2. Correspondence should be addressed to Cao Chuanbao Research center of materials Science Beijing Institute of Technology Beijing China Department of Chemical Engineering Zhengzhou Institute of Light Industry Zhengzhou China

The CNx thin film was deposited on Si(100) substrate from a saturated acetone solution of cyanuric tri-chloride and melamine (cyanuric trichloride/melamine=1︰1.5) at room temperature. X-ray diffraction (XRD) results showed that the diffraction peaks in the pattern coincided well with those of graphite-like carbon nitride calculated in the literature. The lattice constants (a=4.79 ? c=6.90 ) for g-C3N4 matched with those of ab initio calculations (a=4.74 ? c=6.72.? quite well. X-ray photoelectron spectroscopy (XPS) measurements indicated that the elements in the de-posited films were mostly of C and N (N/C=0.75), and N (400.00 eV) bonded with C (2.7.72.eV) in the form of six-member C3N3 ring. The peaks at 800 cm-1, 1310 cm-1 and 1610 cm-1 in the Fourier transform infrared (FTIR) spec-trum indicated that triazine ring existed in the product. These results demonstrated that crystalline g-C3N4 was ob-tained in the CNx film.

关键词：沉淀薄膜饱和丙酮溶液三聚氰胺 X射线衍射石墨碳氮化合物晶格恒量光电子光谱测量法傅立叶变换红外光谱三嗪

An eSnake model for medical image segmentation

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Progress in Natural Science:materials International 2005年第5期15卷 424-429页

作者： Lv Hongyu1, YUAN Kehong2. BAO Shanglian1, ZU Donglin1 and DUAN Chaijie1*(1. The Research center for Tumor Diagnosis and Therapeutical Physics & Beijing Key Laboratory of Medical Physics and Engineering, Beijing 100871, china 2. Key Laboratory of Pure and Applied Mathematics, School of Mathematical Sciences, Peking University, Beijing 100871, china) Beijing Key Lab. of Med. Phys. and Eng. Res. Ctr. for Tumor Diagnosis and Therapeutical Phys. Beijing 100871 China Key Lab. of Pure and Applied Math. Sch. of Math. Sci. Peking Univ. Beijing 100871 China

A novel scheme of external force for detecting the object boundary of medical image based on Snakes (active contours) is introduced in the paper. In our new method, an electrostatic field on a template plane above the original image plane is designed to form the map of the external force. Compared with the method of Gradient Vector Flow (GVF), our approach has clear physical meanings. It has stronger ability to conform to boundary concavities, is simple to implement, and reliable for shape segmenting. Additionally, our method has larger capture range for the external force and is useful for medical image preprocessing in various applications. Finally, by adding the balloon force to the electrostatic field model, our Snake is able to represent long tube-like shapes or shapes with significant protrusions or bifurcations, and it has the specialty to prevent Snake leaking from large gaps on image edge by using a two-stage segmentation technique introduced in this paper. The test of our models proves that our methods are robust, precise in medical image segmentation.

关键词： image segmentation eSnake external force electrostatic field balloon force.

Numerical simulations of self-propelled swimming of 3D bionic fish school

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Science china(Technological Sciences) 2009年第3期52卷 658-669页

作者： WU ChuiJie1 & WANG Liang2.1 State Key Laboratory of Structural analysis for Industrial Equipment, Dalian University of Technology, Dalian 11602., china 2.Research {2. for Fluid Dynamics, People’s Liberation Army University of Science and Technology, nanjing 2.1101, china State Key Laboratory of Structural analysis for Industrial Equipment Dalian University of Technology Dalian China Research center for Fluid Dynamics People’s Liberation Army University of Science and Technology Nanjing China

Numerical simulations of self-propelled swimming of a three dimensional bionic fish and fish school in a viscous fluid are carried out. This is done with the assistance of a parallel software package produced for 3D moving boundary problems. This computational fluid dynamics package combines the adaptive multi-grid finite volume method, the immersed boundary method and VOF (volume of fluid) method. By using the package results of the self-propelled swimming of a 3D bionic fish and fish school in a vis- cous fluid are obtained. With comparison to the existing experimental measurements of living fishes, the predicted structure of vortical wakes is in good agreement with the measurements.

关键词： adaptive multi-grid immersed boundary method self-propelled swimming fish school 3D bionic fish

Predictive Values of Body Mass Index and Waist Circumference for Risk Factors of Certain Related Diseases in Chinese Adults - Study on Optimal Cut-off Points of Body Mass Index and Waist Circumference in Chinese Adults

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Biomedical and Environmental Sciences 2002年第1期15卷 83-96页

作者： ZHOU BEI-FAN2.ooperative Meta-analysis Group of the Working Group on Obesity in china Cooperative Meta-analysis Group of the Working Group on Obesity in china

Objective For prevention of obesity in Chinese population, it is necessary to definethe optimal range of healthy weight and the appropriate cut-off points of BMI and waistcircumference for Chinese adults. The Working Group on Obesity in china under the supportof International Life Sciences Institute Focal Point in china organized a meta-{2. on therelation between BMI, waist circumference and risk factors of related chronic diseases (e. g.,high diabetes, diabetes mellitus, and lipoprotein disorders). Methods 13 population studiesin all met the criteria for enrollment, with data of 2.9 972.adults (2.-70 year) surveyed inthe 1990s. Data on waist circumference was available for 111411 persons and data on serumlipids and glucose were available for more than 80 000. The study populations located in2.provinces, municipalities and autonomous regions in china's Mainland as well as inTaiwan. Each enrolled study provided data according to a common protocol and uniformformat. The center for data management in Department of Epidemiology, Fu Wai Hospitalwas responsible for statistical {2.. Results and conclusion The prevalence ofhypertension, diabetes, dyslipidemia and clustering of risk factors all increased withincreasing levels of BMI or waist circumference. BMI at 2. with best sensitivity andspecificity for identification of the risk factors, was recommended as the cut-off point foroverweight, BMI at 2. which may identify the risk factors with specificity around 90 % wasrecommended as the cut-off point for obesity. Waist circumference beyond 85 cm for menand beyond 80 cm for women were recommended as the cut-off points for central *** of population attributable risk percent illustrated that reducing BMI to normalrange (2.) could prevent 45%-50% clustering of risk factors. Treatment of obese persons(BMI≥2.)with drugs could prevent 15%-17% clustering of risk factors. The waistcircumference controlled under 85 cm for men and under 80 cm for women

关键词： Chinese adults Overweight Obesity BMI Waist circumference

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth Sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2.& LU Yang1,3 1. Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, china 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 3. Unite {2. for Astro-geodymics Research, Chinese Academy of Sciences, Shanghai 2.0030, china Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China Graduate School of the Chinese Academy of Sciences Beijing China Unite center for Astro-geodymics Research Chinese Academy of Sciences Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 2.0 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Combined adjustment project of national astronomical geodetic networks and 2.00' national GPS control network

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Progress in Natural Science:materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2. SONG Lijie3, WEI Ziqing1, WANG Zhouping2. OUYANG Guichong2. XU Bilin2. WU Xiaoping3 and WANG Junqin4(1. Xi'an Research Institute of Surveying and Mapping, Xi'an 710054, china 2. Xi'an Informational and Technical center of Surveying and Mapping, Xi'an 710054, china 3. Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. china 4. The First Surveying Team of Tianjin, Tianjin 300140, china) Xi'an Res. Inst. of Surveying and Mapping Xi'an 710054 China Xi'an Info. and Technical Ctr. of Surveying and Mapping Xi'an 710054 China Zhengzhou Inst. of Surveying and Mapping Zhengzhou 450052 China First Surveying Team of Tianjin Tianjin 300140 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2.00' national GPS control network involve 48519 terrestrial observational stations and 2.66 GPS observational stations. In the terrestrial network, 2.107 stations are height fixed and 2.412.stations are in three dimensions. 440793 terrestrial observations and 183668 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2.m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12.m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3 m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

Influence of Formate on Bioactivity Material-thuringiensin Synthesized by Bacillus thuringiensis YBT-032

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Journal of Wuhan University of Technology(materials Science) 2008年第5期23卷 691-693页

作者：王志喻子牛 College of Bioengineering Hubei University of Technology State Key Laboratoy of Agricultural Microbiology National Engineering Research center for Microbial Posticides Huazhong Agricultural University

The biological method to synthesize thuringiensin and the influence of formate on thuringiensin biosynthesis were investigated. Addition of 1.00 g/L formate to growth medium of bacillus thuringiensis YBT-032.resulted in significant enhancements in productions of citrate, α -ketoglutarate, intracellular adenine and thuringiensin. These results demonstrate that added formate attends metabolism of cell, facilitates carbon metabolic flux in tricarboxylic acid cycle and hexose monophosphate pathway. As a carbon source, formate facilitates cell growth, increases glucose consumption and enhances the ability of cell to synthesis adenine analogues, and subsequently thuringiensin. Thuringiensin production rate significantly enhanced from 6.44 to 8.46 mg·g^-1 · h and transformation ratio from glucose to thuringiensin increased by 43.30%.

关键词： bacillus thuringiensis precursor formate thuringiensin

Molecular hosts for triplet emitters in organic light-emitting diodes and the corresponding working principle

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Science china Chemistry 2010年第8期53卷 1679-1694页

作者： MI BaoXiu1,2.GAO ZhiQiang1,LIAO ZhangJin2.HUANG Wei2.& CHEN Chin Hsin3 1Jiangsu Engineering center for Flat-Panel Displays & Solid-State Lighting School of materials Science & Engineering,{2. University of Posts & Telecommunications,{2. 2.0046,china 2.ey Laboratory for Organic Electronics & Information Displays (KLOEID),Institute of Advanced materials (IAM),{2. University of Posts & Telecommunications,{2. 2.0046,china 3Display Institute,Microelectronics and Information Systems Research center,National Chiao Tung University Hsinchu,Hsinchu,300 china Jiangsu Engineering center for Flat-Panel Displays & Solid-State Lighting School of materials Science & Engineering Nanjing University of Posts & Telecommunications Nanjing China Key Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing China Display Institute Microelectronics and Information Systems Research Center National Chiao Tung University Hsinchu Hsinchu China

This paper summarizes the mechanism and routes for excitation of triplet emitters in dopant emission based phosphorescent organic light-emitting diodes (PhOLEDs),providing a comprehensive overview of recent progress in molecular hosts for triplet emitters in ***,based on the nature of different hosts,e.g.,hole transporting,electron transporting or bipolar materials,in which the dopant emitters can be hosted to generate phosphorescence,the respective device performances are summarized and *** are given to the relationships among the molecular structure,thermal stability,triplet energy,carrier mobility,molecular orbital energy level and their corresponding device performances.

关键词： phosphorescent organic light-emitting diodes (OLEDs) working principle electrophosphorescence hosts triplet emitter

Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china Chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. Chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, china 2. Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 13002., china Chemistry and Chemical Engineering College of Henan University Kaifeng China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.