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Repetitious-Hot-Pressing Technique in Hot-Pressing Process

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Journal of Materials Science & Technology 2003年第5期19卷 486-488页

作者： Shixue SONG, Xing AI, Wei GAO and Jun ZHAO1.school of Mechanical Engineering, {1. University, jinan 2.0061. china2.school of Science, jinan University, jinan 2.002., china school of Mechanical Engineering Shandong University Jinan 250061 China school of Science Jinan University Jinan 250022 China

A new pressing method was proposed for hot-pressing process. Experimental results indicated that the porosity in Al2.3/TiC/ Ni/Mo (hereafter called AI2.3/TiC composite) composite compacts decreases by 6% after adopting this new technique, compared to traditional hot-pressing technique under the same sintering temperature. The flexural strength and Vicker hardness increase from 883 MPa to 980 MPa and from 1. GPa to 2.0}1.GPa, respectively. A theoretical model was given to analyze the densification mechanism of the composite in the process of repetitious-hot-pressing.

关键词： Hot-pressing sintering Repetitious-hot-pressing sintering Composite

Cubic surface fitting to image by combination

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Science china(Information Sciences) 2010年第7期53卷 1287-1295页

作者： LI XueMei1. ZHANG CaiMing1.2. YUE YiZhen1.& WANG KunPeng1.1.0} of Computer Science and Technology, {1. University, jinan 2.01.1. china 2.10} of Computer Science and Technology, {1. Economics University, jinan 2.001., china 1. school of Computer Science and Technology Shandong University Jinan 250101 China2. School of Computer Science and Technology Shandong Economics University Jinan 250014 China

We present a new method for constructing a fitting surface to image data. The new method is based on a supposition that the given image data are sampled from an original scene that can be represented by a surface defined by piecewise quadratic polynomials. The surface representing the original scene is known as the original surface in this paper. Unlike existing methods, which generally construct the fitting surface to the original surface using image data as interpolation data, the new method constructs the fitting surface using the image data as constraints to reverse the sampling process, which improves the approximation precision of the fitting surface. Associated with each data point and its near region, the new method constructs a quadratic polynomial patch locally using the sampling formula as constraint. The quadratic patch approximates the original surface with a quadratic polynomial precision. The fitting surface which approximates the original surface is formed by the combination of all the quadratic polynomial patches. The experiments demonstrate that compared with Bi-cubic and Separable PCC methods, the new method produced resized images with high precision and good quality.

关键词： surface fitting quadratic polynomial image resizing reversing

Sol-gel preparation and spectroscopic study of the pyrophanite MnTiO_3 nanoparticles

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Science china Chemistry 2005年第3期48卷 210-215页

作者： ZHOU Guowei1. KANG Youngsoo2. LI Tianduo1.& XU Guiying3 1. school of Light Chemicals and Environmental Engineering, {1. Institute of Light Industry, jinan 2.01.0, china 2. Department of Chemistry, Pukyong National University, Daeyeon-3-dong, Nam-gu, Pusan 608-737, Korea 3. Key Laboratory for Colloid and Interface of Ministry of Education of china, {1. University, jinan 2.01.0, china 1. school of Light Chemicals and Environmental Engineering Shandong Institute of Light Industry 250100 Jinan China 2. Department of Chemistry Pukyong National University Daeyeon-3-dong Nam-gu 608-737 Pusan Korea 3. Key Laboratory for Colloid and Interface of Ministry of Education of china Shandong University 250100 Jinan China

The nanosized xerogel of titanium dioxide (TiO2. and manganese oxides (MnO2. Mn2.3, Mn3O4) was prepared by the sol-gel method using manganese chloride (MnCl2.4H2.) and titanium isopropoxide (Ti(O-iPr)4) as precursors in cetyltrimethylammonium bromide (CTAB)/ ethanol/H2./HCl micelle solutions, following the calcinations of the produced powders at differ-ence temperatures. The nanostructure and phase composition of these nanoparticles were characterized with X-ray powder diffraction (XRD), transmission electron microscopy (TEM), en-ergy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The spectroscopic characterizations of these nanoparticles were also done with UV-Vis spectroscopy and laser Raman spectroscopy (LRS). XRD patterns show that the pyrophanite MnTiO3 phase was formed at the calcinations temperature of 900℃. The TEM images show that the nanoparti-cles are almost spherical or slight ellipose and the sizes are 50 nm on average. The UV-Vis spectra show that the nanosized MnTiO3 have significant absorption bands in the visible region. There are new absorption peaks of MnTiO3 nanoparticles in LRS compared with the pure TiO2.powder.

关键词： pyrophanite MnTiO3, nanoparticles, spectroscopy, CTAB micelle, sol-gel.

MULTI-DIMENSIONAL REFLECTED BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS AND THE COMPARISON THEOREM

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Acta Mathematica Scientia 2010年第5期30卷 1819-1836页

作者：吴臻消华 school of Mathematics Shandong University school of Mathematics and Statistics Shandong University at Weihai

In this article, we study the multi-dimensional reflected backward stochastic differential equations. The existence and uniqueness result of the solution for this kind of equation is proved by the fixed point argument where every element of the solution is forced to stay above the given stochastic process, i.e., multi-dimensional obstacle, respectively. We also give a kind of multi-dimensional comparison theorem for the reflected BSDE and then use it as the tool to prove an existence result for the multi-dimensional reflected BSDE where the coefficient is continuous and has linear growth.

关键词： backward stochastic differential equations comparison theorem local time

Medical image segmentation using improved FCM

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Science china(Information Sciences) 2012年第5期55卷 1052-1061页

作者： ZHANG XiaoFeng 1.2.ZHANG CaiMing 1.3,4,TANG WenJing 1.2.& WEI ZhenWen 1.1.school of Computer Science and Technology,{1. University,jinan 2.01.1.china 2.school of Information and Electrical Engineering,Ludong University,Yantai 2.402.,china 3 school of Computer Science and Technology,{1. University of Finance and Economics,jinan 2.001.,china 4 {1. Province Key Lab of Digital Media Technology,jinan 2.001.,china 1. school of Computer Science and Technology Shandong University Jinan 250101 China2. School of Information and Electrical Engineering Ludong University Yantai 264025 China3. School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China4. Shandong Province Key Lab of Digital Media Technology Jinan 250014 China

Image segmentation is one of the most important problems in medical image processing,and the existence of partial volume effect and other phenomena makes the problem much more *** C-means,as an effective tool to deal with PVE,however,is faced with great challenges in *** at this,this paper proposes one improved FCM algorithm based on the histogram of the given image,which will be denoted as HisFCM and divided into two *** first phase will retrieve several intervals on which to compute cluster centroids,and the second one will perform image segmentation based on improved FCM *** with FCM and other improved algorithms,HisFCM is of much higher efficiency with satisfying *** on medical images show that HisFCM can achieve good segmentation results in less than 0.1.second,and can satisfy real-time requirements of medical image processing.

关键词： FCM histogram image segmentation medical image processing

Expression of prolactin receptor and response to prolactin stimulation of human NK cell lines

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Cell Research 2004年第1期14卷 67-73页

作者： Rui SUN~(1.2.), Ai Ling LI~(2.), Hai Ming WEI~1. Zhi Gang TIAN~(1.2.**) ~1.0} of Life Sciences, University of Science and Technology of{1., Hefei 2.002., Anhui,{1.. ~2.7} Cancer Biotherapy Center, shandong Academy of Medical Science, jinan 2.0062. shandong,{1.. 2.0} Cancer Biotherapy Center Shandong Academy of Medical Science Jinan 250062 Shandong China. 2.0} Cancer Biotherapy Center Shandong Academy of Medical Science Jinan 250062 Shandong China. 1.0} of Life Sciences University of Science and Technology of China Hefei 230027 Anhui China. 2.0} Cancer Biotherapy Center Shandong Academy of Medical Science Jinan 250062 Shandong China.

We have previously shown a critical role of prolactin (PRL) during maturation and anti-tumor effects of murine natural killer (NK) cells in vitro and in vivo. We extended that study by exploring the ability of human NK cell lines (NK-92.and YT cell) to express PRL receptor (PRL-R) and to respond to PRL stimulation in vitro. Both human NK cell lines constitutively expressed PRL-R on membrane and mRNA transcripts, NK-92.cells contained higher level of PRL-R than YT cells, which correlated to the enhanced capacity of the cells to proliferate and to lyse target cells in response to PRL stimulation in the presence of trace amount of IL-2.or IL-1. in vitro. Two differences between IL-2.and IL-1. in functioning on human NK cells were for the first time observed. PRL synergized with IL-1. to improve proliferation of NK cells in a dose-dependent manner without double peak manifesting like IL-2. Although PRL enhanced the cytotoxicity of IL-2.or IL-1. activated NK cells, it exerted the function through up-regulati

关键词： prolactin receptor NK cell interleukin-2 interleukin-1..

Analysis of the carbon source for diamond crystal growth

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Chinese Science Bulletin 2008年第6期53卷 937-942页

作者： LI Li1.2. XU Bin2.3 & LI MuSen1.2.1.school of Materials Science & Engineering, {1. University, jinan 2.0061. china 2.{1. Engineering Research Center for Super Hard Materials, Zoucheng 2.3500, china 3 school of Materials Science & Engineering, {1. Jianzhu University, jinan 2.01.1. china school of Materials Science & Engineering Shandong University Jinan China shandong Engineering Research Center for Super Hard Materials Zoucheng China school of Materials Science & Engineering Shandong Jianzhu University Jinan China

The lattice constants of diamond and graphite at high pressure and high temperature (HPHT) were calculated on the basis of linear expansion coefficient and elastic constant. According to the empirical electron theory of solids and molecules (EET), the valence electron structures (VESs) of diamond, graphite crystal and their common planes were calculated. The relationship between diamond and graphite structure was analyzed based on the boundary condition of the improved Thomas-Fermi-Dirac theory by Cheng (TFDC). It was found that the electron densities of common planes in graphite were not continuous with those of planes in diamond at the first order of approximation. The results show that during the course of diamond single crystal growth at HPHT with metal catalyst, the carbon sources forming diamond structure do not come from the graphite structure directly. The diamond growth mechanism was discussed from the viewpoint of valence electron structure.

关键词：钻石晶体生长石墨碳源价电子结构

Thermochemical Evaluation of Combustion Synthesis of Al_2._3/B_4C Composite

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International Journal of Minerals,Metallurgy and Materials 1998年第2期12卷 90-92页

作者： Yonghe Liu~(1.2.) Sheng Yin~(1.) Weijing Zhang~(1.) Hoyi Lai~(1.) 1. Materials Science and Engineering school, UST Beijing, Beijing 1.0083,{1. 2. school of Materials Science and Engineering, shandong University of Technology, jinan 2.001. Materials Science and Engineering school UST Beijing Beijing 100083 China school of Materials Science and Engineering Shandong University of Technology Jinan 250014 China

The equilibrium phase and adiabatic temperature for combustion synthesis of Al_2._3/B_4C employing Al, B_2._3 and C as starting materials is analyzed by both conventional and CALPHAD method. The adiabatic temperature calculed by CALPHAD method is significantly lower than that obtained by conventional method. The CALPHAD calculation also reveals that the equilibrium phases presented at the adiabatic temperature are different to the desired composites. The adiabatic temperature in this system can be lowered by introducing Al_2._3 as diluents. The maximum amount of Al_2._3 that can be added to the system while maintain a self-sustaining combusion mode is 1.3 mol.

关键词： thermochemical evaluation SHS Al_2._3/B_4C composite

Analysis and Modeling on the Spatial Structure of Urban Land Use: A Case of jinan,{1.

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Chinese Journal of Population,Resources and Environment 2007年第2期5卷 34-40页

作者： Zhao Huixia1. 3, Zhang Zulu2. Jiang Luguang 1.1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1. china 2. College of Population, Resources and Environment, {1. Normal University, jinan {1. 2.001., china 3. Graduate {12. of the Chinese Academy of Sciences, Beijing 1.0039, china Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China Graduate school of the Chinese Academy of Sciences Beijing 100039 China College of Population Resources and Environment Shandong Normal University Jinan Shandong 250014 China

Based on the data of urban land use obtained by remote sensing interpretation from aero images in 1.86 and 2.04, the spatial structure of jinan is studied in this paper with the method of Geographic Information System (GIS). According to the proportion of land for residence, industry and commerce, the urban district can be distinguished into three rings. Compared with the traditional theory of the ring structure in Western coun- tries, they have many distinctive characteristics. The main func- tions of the inner ring include residence, business and banking, but the proportion of residential land (more than 50%) is considerably higher than that of the cities in Western countries. The land proportion for residence and industry in the intermediate ring is equal on the whole. The main land of the outside ring is for industrial use. From 1.86 to 2.04, great changes have taken place on the land proportion of different types of use. In the inner ring, the land for residential and industrial use has shrunk much while the land for commercial use has increased. In the intermediate ring, the changes of the three types of land use were not very much and the temporal variation was relatively stable. On the contrary, the structure in the outside ring varies acutely. Though most of it is also for industrial use, the proportion of residential land has in- creased much. The three rings can also be divided into several sectors respectively, according to the function of land use clusters. New trends and mechanisms of the changes of land use impacting the urban structure were proposed in the end of the paper.

关键词： urban land use ring structure sector structure jinan