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Pre-LOI trajectory maneuvers of the CHANG'E-2.libration point mission

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Science china(Information Sciences) 2012年第6期55卷 1249-1258页

作者： WU WeiRen 1,LIU Yong 2.3.LIU Lei 2.3.ZHOU JianLiang 3.TANG GeShi 2.3.& CHEN YongZhi 3.1 Chinese Lunar Exploration and Space Project center,Beijing 10003.,china 2.Science and Technology on aerospace Flight Dynamics Laboratory,Beijing {3.,china 3.Beijing aerospace control center,Beijing {3.,china Chinese Lunar Exploration and Space Project center Beijing China Science and Technology on aerospace Flight Dynamics Laboratory Beijing China Beijing aerospace control {2. Beijing China

This paper addresses pre-LOI (before Lissajous orbit insertion) trajectory maneuvers for the libration point mission of CHANG'E-2.which is the first Chinese satellite to fly to the Sun-Earth L2.libration point and the first satellite ever to fly to the L2.point from lunar ***,a transfer trajectory for the mission is designed based on InterPlanetary Superhighway theory under the constraint of the remaining propellant,TT&C (telemetry,track and command) and sunlight *** effects of trajectory maneuver errors on the mission are also ***,based on the analysis results,the article investigates the trajectory maneuver schemes for the lunar escape and transfer trajectory maneuvers employing mathematical models and operational *** mission status based on our maneuver schemes is then presented,and the results of control operation and corresponding analysis are provided in ***,the future trajectory maneuver in the Lissajous orbit is *** to the analysis of the CHANG'E-2.TT&C data,the trajectory maneuver schemes proposed in the article work properly and efficiently.

关键词： CHANG’E-2 libration point trajectory maneuver escape trajectory transfer trajectory

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution control and Resource Reuse,School of the Environment,Nanjing University,Nanjing 2.0093.china 2. Nanjing College of Chemical Technology,Nanjing 2.0048,china 3. Jiangsu Engineering & Technology Research {3. for Organic Toxicant control and Resource Reuse,Nanjing 2.003.,china State Key Laboratory of Pollution control and Resource Reuse School of the Environment Nanjing University Nanjing China Nanjing College of Chemical Technology Nanjing China Jiangsu Engineering & Technology Research center for Organic Toxicant control and Resource Reuse Nanjing China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

Secreted Protein HP12.6 of Helicobacter pylori Strain 2.695 Induces Apoptosis of AGS Cells

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Biomedical and Environmental Sciences 2012年第6期25卷 614-619页

作者： LI Jing 1,2. , MENG Fan Liang 1,2. , HE Li Hua 1,2., and ZHANG Jian Zhong 1,2. 1. National Institute for Communicable Disease control and Prevention, Chinese center for Disease control and Prevention, Beijing 102.06, {3. 2. State Key Laboratory for Infectious Disease Prevention and control, Chinese center for Disease control and Prevention, Beijing 102.06, {3. National Institute for Communicable Disease control and Prevention Chinese Center for Disease Control and Prevention Beijing 102206 China State Key Laboratory for Infectious Disease Prevention and control Chinese Center for Disease Control and Prevention Beijing 102206 China

Objective Secreted proteins of Helicobacter pylori （H. pylori） interact with gastric epithelium cells and may contribute to cell damage. Considering the fact that HPO17S and hypothetical conserved protein HP12.6 are included in the group and that HP0175 is a well-known apoptosis-induced factor, the present study aims to clarify whether HP12.6 plays a role in bacterial pathogenicity or even functions as an apoptosis-induced factor in human stomach. Methods Two genes encoding HP12.6 and HPO175 were cloned into pET3.a vector and expressed as recombinant proteins in Escherichia coil （E. coil） BL2.. Signal peptide sequences were not included. The recombinant proteins were purified with His SpinTrap and desalted by using HiTrap Desalting. Immunoreactivity of the proteins was determined by Western blot. Human gastric epithelial cell AGS was challenged with these endotoxin-free proteins; and apoptosis of cells was assayed with the Cell Death ELISA kit. Results Recombinant proteins and their respective products whose N-terminal his-tag were removed with thrombin were recognized by serum from the patient infected with H. pylori. Apoptotic AGS cells challenged by HP12.6 of H. pylori 2.695 were four times more than untreated cells. In addition, apoptosis-induced ability of HP12.6 of SS1 was not as strong as that of H. pylori 2.695 strain. Conclusion HP12.6 of H. pylori 2.695 induces apoptosis of AGS cells in a time-dependent manner, however the apoptosis-induced ability of HP12.6 may differ due to variations between different strains.

关键词： H. pylori HP12.6 AGS Apoptosis

2.2.年8月中国甲乙丙类传染病疫情动态概要

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疾病监测 2024年第9期 1096-1097页

作者： Division of Infectious Disease, Chinese center for Disease control and Prevention 中国疾病预防控制中心传染病预防控制处

2.2.年8月（2.2.年8月1日0:00至8月3.日2.:00），全国（不含香港、澳门特别行政区和台湾省，下同）共报告法定传染病719 686例，死亡2.3.6例。与上月相比，报告发病数下降15.9%，死亡数减少65例。甲类传染病报告发病6例，为鼠疫（2.）...

2.2.年8月（2.2.年8月1日0:00至8月3.日2.:00），全国（不含香港、澳门特别行政区和台湾省，下同）共报告法定传染病719 686例，死亡2.3.6例。与上月相比，报告发病数下降15.9%，死亡数减少65例。甲类传染病报告发病6例，为鼠疫（2.）和霍乱（4例），报告死亡1例，为鼠疫死亡病例。

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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, {2. 2. Xi'an Informational and Technical center of Surveying and Mapping, Xi'an 710054, {2. 3. Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. {2. 4. The First Surveying Team of Tianjin, Tianjin 3.0140, {2.) 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 2.1}12.stations are in three dimensions. 440793.terrestrial observations and 183.68 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.

A new navigation approach of terrain contour matching based on 3.D terrain reconstruction from onboard image sequence

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Science china(Technological Sciences) 2010年第5期53卷 1176-1183页

作者： LI LiChun1,2.YU QiFeng2.SHANG Yang2.YUAN Yun2.LU HongWei3.& LIU XiaoLin4 1 Beijing aerospace {2. center,Beijing {3.,china 2.College of aerospace and Material Engineering,National University of Defense Technology,Changsha 410073.china 3.Equipment Research Institute of PLA’s Second Artillery,Beijing 100085,china 4 College of Mechatronic Engineering and Automation,National University of Defense Technology,Changsha 410073.china Beijing aerospace control {2. Beijing China College of aerospace and Material Engineering National University of Defense Technology Changsha China Equipment Research Institute of PLA’s Second Artillery Beijing China College of Mechatronic Engineering and Automation National University of Defense Technology Changsha China

This article presents a passive navigation method of terrain contour matching by reconstructing the 3.D terrain from the image sequence(acquired by the onboard camera).To achieve automation and simultaneity of the image sequence processing for navigation,a correspondence registration method based on control points tracking is proposed which tracks the sparse control points through the whole image sequence and uses them as correspondence in the relation geometry ***,a key frame selection method based on the images overlapping ratio and intersecting angles is explored,thereafter the requirement for the camera system configuration is *** proposed method also includes an optimal local homography estimating algorithm according to the control points,which helps correctly predict points to be matched and their speed ***,the real-time 3.D terrain of the trajectory thus reconstructed is matched with the referenced terrain map,and the result of which provides navigating *** digital simulation experiment and the real image based experiment have verified the proposed method.

关键词： terrain contour matching vision-based navigation 3.D reconstruction control points key frame registration optimal local homography

Flatness and Profile Integration control Model for Tandem Cold Mills

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Journal of Iron and Steel Research International 2012年第3期19卷 31-37页

作者： SHAN Xiu-ying1,2.3. LIU Hong-min1,2. JIA Chun-yu1,2. SUN Jian-liang1,2.(1. Engineering Research center of Rolling Equipment and Complete Technology of Ministry of Education, Yanshan University, Qinhuangdao 066004, Hebei, {2. 2. State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, {2. 3. Hot Tandem Rolling Factory, Jinan Iron and Steel Co Ltd, Jinan 2.0101, Shandong, {2.) Engineering Research center of Rolling Equipment and Complete Technology of Ministry of Education Yanshan University Qinhuangdao Hebei China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao Hebei China Hot Tandem Rolling Factory Jinan Iron and Steel Co Ltd Jinan Shandong China

Using the effective matrix methods of flatness and profile control synthetically, the flatness and profile in- tegration control scheme for tandem cold mills is built in order to increase flatness and profile control precision of tan- dem cold mills. Corresponding control strategies are adopted for various control objectives of different stands and the coordination control strategies of various stands are given, which makes the on-line flatness control cooperate with on-line profile control and implements the parallel control of different stands. According to the measured flatness and profile data of some 1550 mm tandem cold mills, the control scheme is verified and the result indicates that the scheme has high flatness and profile control precision with steady and reliable control process. A new way and method is supplied for researching shade control of tandem cold mills.

关键词： flatness profile shape effective matrix tandem cold mill

Scale correlation between vegetation and soil in larch forest, NE china

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Journal of Environmental Sciences 2001年第1期13卷 51-57页

作者： MA Ke ming 1, ZU Yuan gang 2. Michel Godron 3.(1. Reserch center for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, {2.. E mail: mkm@*** 2. Open Research Laboratory of Forest Plant Ecology, Northeast Fo Research center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. E-mail:[email protected] Open Research Laboratory of Forest Plant Ecology Northeast Forest University Harbin 150040 China CCAS La Graineterie 18410 Brinon France

After the analysis on the linages of species, the fractal dimensions of vegetation and soil in a managed larch(Larix gmelini) forest in Daxingan Mountains, NE china were estimated separately, and their scale correlation was discussed. (1) The dominant species of the larch forest, larch and the important accompany species, birch (Betula platyphylla) were homogeneously distributed along the transect. The other species were heterogeneous, and can be divided into three groups located on the right, left and central parts of the transect respectively. The transect can be separated into two parts at the position for the 2.th quadrat(580m). (2. The fractal dimension in the large scale range from 2.0 to 400m was lower than that in the small scale range from 0 to 2.0m in the forest, indicating the different variation regularities of spatial heterogeneity in different scale ranges. The inflection point at 2.0m was one of the key scales of spatial hierarchy of the larch forest. (3. The scale variation of the forest was correlated with that of soil pH on large scales, which reflected the indirect {2. of the dominant species to the spatial pattern and species distribution of understorey by changing soil acidity in the forest and the indirect effects of forest management.

关键词： fractal dimension larch forest scale variation soil spatial heterogeneity species linkX

controlled Size and Density Distribution of Nanoparticles by Thermal Ammonia Etching Method

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 108-111页

作者：李刚 Key Laboratory of Ministry of Education for Conveyance and Equipment East China Jiaotong University center for Photon Fabrication Science and Technology Jiangsu University

Nickel nanometer catalyst thin films were prepared on SiO2.Si substrates using sputtering coater. The effects of ammonia pretreatment on the catalyst films from continuous film to the nanoparticles were investigated. The nanostructures of the Ni thin films as a function of the catalyst film original thickness, the pretreatment time and temperature were discussed. The optimum parameters of etching process were obtained, and the functional mechanism of ammonia was primarily analyzed. Scanning electron microscopy （SEM） and atomic force microscopy （AFM） were used to evaluate the obtained nanoparticles. It is demonstrated that the controlled size and density distribution of the nanoparticles can be achieved by employing ammonia etching method.

关键词： ammonia etching nanoparticle density control thermal expansion