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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 100094,china 3.Beijing Aerospace Control center,Beijing 100094,china 1. Chinese Lunar Exploration and Space Project center Beijing 100037 China2. Science and Technology on Aerospace Flight Dynamics Laboratory Beijing 100094 China3. Beijing Aerospace Control Center Beijing 100094 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

Zeolite NaY-mediated oxidation of dyes with H_2O_2: unique heterogeneous non-transition metal center cleavage of H_2O_2 under visible light irradiation

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Science china Chemistry 2007年第6期50卷 770-775页

作者： LIU LiLi1, MA WanHong1, SONG WenJing1, CHEN ChunCheng1, LIN Jun2, ZHAO JinCai1, QIAN XinHua3.& ZHANG ShiBo3.1 Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, china 2 Department of Chemistry, Renmin University of china, Beijing 100872, china 3.Fushun Petrochemical Company, Petro{3. Company Limited, Fushun 113.08, china Institute of Chemistry Chinese Academy of SciencesBeijing 100080China Department of Chemistry Renmin University of ChinaBeijing 100872China Fushun Petrochemical Company PetroChina Company LimitedFushun 113008China

This study investigated the visible-light catalysis mediated by zeolite NaY on the oxidation of dyes with H2O2. The results demonstrated that zeolite NaY acts as a sink for the electron from the photo-excited dye in the heterogeneous catalysis. Furthermore, the electron can effectively activate H2O2 to produce ?OH radical that is a powerful oxidant for the oxidation of dye at room temperature. The effects of the framework topology, Si/Al ratio, and exchangeable cation of the zeolite on the oxidation of various dyes were also shown.

关键词： photooxidation, zeolite NaY, dye, hydrogen peroxide, visible light

Comparison of the influence factors on NDVI for CCD camera and WFI imager on CBERS-02

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Science china(Technological Sciences) 2005年第S2期48卷 100-115页

作者： YU Tao1,3. LI Xiaoying1,2,3. ZHANG Yong1,2,3. ZHAO Feng1,2,3. GU Xingfa1,3.4, ZHU Li1,2,3. WANG Pengxin5 & MIN Xiangjun6 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application, CAS, Bei- jing 100101, china 2. Graduate University of Chinese Academy of Sciences, Beijing 10003., china 3. The center for National Spaceborne Demonstration, Beijing 100101, china 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. College of Information and Electrical Engineering, china Agricultural University, Beijing 100083. china 6. china center for Resource Satellite Data and Application, Beijing 10083., china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Application CAS 100101 Beijing China 2. The center for National Spaceborne Demonstration 100101 Beijing China 3. Graduate University of Chinese Academy of Sciences 100039 Beijing China 4. Institut National de la Recherche Agronomique Climat Sol Environnent 84914 Avignon France 5. College of Information and Electrical Engineering China Agricultural University 100083 Beijing China 6. china center for Resource Satellite Data and Application 100830 Beijing China

CCD and WFI are payloads in the visible light and near infrared bands on CBERS satellites and they have not been applied widely, especially WFI. This article mainly probes into the potential of these two sensors’ application in the vegetation monitoring and analyses the influences of radiometric calibration, atmosphere conditions and sun-observing geometry, etc. on NDVI obtained from these two sensors respectively. In addition it analyses the effect of the spectral response difference of red and near infrared spectral bands in CCD and WFI sensors on NDVI. Results indicate that radiometric calibration is the most important factor on NDVI, which cannot be applied to vegetation monitoring without radiometric calibration. Results also demonstrate that near surface NDVI is different greatly from that of TOA which change with atmosphere conditions. The study shows that NDVI is also affected by the non-lambertian character of surface and the change of the atmospheric path with the observing geometry. And NDVI of WFI is higher than that of CCD. They are very different because of their spectral difference, but they have a good linear relevant relationship.

关键词： CCD WFI NDVI LAI.

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3.,HUANG Zhiqin 2, 3. 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, china 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049, china 4. Information {3. of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, china The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of the Chinese Academy of Sciences 100049 Beijing China Information center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Deep-Cut Vacuum Distillation in the 10 Mt/a CDU/VDU

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china Petroleum Processing & Petrochemical Technology 2009年第2期11卷 9-13页

作者： Lin Zhuwei1 Mao Fuzhong1 Jiang Bing2 Chen Kaibei3.Chi Ling3.Yan Chun3.1. KBC Advanced Technologies(Beijing) Co.,Ltd. Beijing 100029 2. The National Engineering Research center for Rectification Technology,Tianjin University 3. SINOPEC Engineering Incorporation) KBC Advanced Technologies (Beijing) Co. Ltd. Beijing 100029 China National Engineering Research center for Rectification Technology Tianjin University China SINOPEC Engineering Incorporation China

This article introduces the concepts relating to deep-cut vacuum distillation and its suitability,and analyzes the deep-cut vacuum distillation technique licensed by the KBC Advanced Technologies to the 10 Mt/a CDU/VDU of the Qingdao refinery and makes comparison on the test run data after commissioning of the distillation unit. The test results have confirmed that the operation of the CDU/VDU had reached the expected goal to achieve good social and economic benefits.

关键词： CDU/VDU deep cut under vacuum distillation rate

Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3. GONG A-du2, 3.1. School of Surveying & Land Information Engineering, Henan Polytechnic University, Jiaozuo 454000, china 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, china 3. Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, china [a] School of Surveying & Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China [b] Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China [c] Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2, SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3. SUN Xinmin3. ZHAO Wenjun3.& CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 450052, china 2. Department of Physics, Beijing Normal University, Beijing 100875, china 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. Institute of Modern Physics, Fudan University, Shanghai 20043., china Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of Physics Beijing Normal University Beijing 100875 China Institute of Cultural Relic Archaeology of Henan Province Zhengzhou 450000 China Institute of Modern Physics Fudan University Shanghai 200433 China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

Dispersion of ventricular mRNA of RyR2 and SERCA2 associated with arrhythmogenesis in rats

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Acta Pharmacologica Sinica 2004年第6期25卷 36-41页

作者： Hong-lan WANG, De-zai DAI2, Feng GAO3. Yan-pin ZHANG3. Feng LU Research Division of Pharmacology, china Pharmaceutical University, Nanjing 210009, china 3.aboratorial center ofMedicine, Southeast University, Nanjing 210009, china Research Division of Pharmacology China Pharmaceutical University Nanjing 210009 China

AIM: To investigate the effect of CPU86017 on the changes of mRNA abundance of different calcium handling system in infarcted heart. METHODS: Rats were subjected to left coronary ligation to induce myocardial infarc- tion (MI). The treatment with either propranolol (Pro) 5 mg/kg ip or CPU86017 1, 2, and 4 mg/kg ip was initiated on the next day of operation and continued for 20 d. Medication with isoproterenol (Isop) 3.mg/kg sc started on the d 17-21. Ventricular mRNA abundance of ryanodine receptor 2 (RyR2), sarcoplasmic reticulum Ca2+-ATPase (SERCA2), L-type Ca2+ channel, and Na+/Ca2+exchanger (NCX1) were measured. RESULTS: Arrhythmic scores (AS) in the Isop group was raised up to 5.27±1.75 (P3. The AS was depressed by Pro (1.63.1.53. P3.00±1.24, and 1.70±1.85, P<0.01 vs Isop). The significant dispersion of depressed mRNA abundance of RyR2 and SERCA2 was associated with an increase in AS in Isop group, and it was much depressed in the left than the right ventricle. The dispersion and depression of mRNA were restored significantly by Pro and CPU86017, asso- ciated with suppression on AS. In Isop group, the mRNA abundance of L-type Ca2+ channel was not changed; and a moderate increase in the mRNA of NCX1 was seen, the changes were regressed by Pro and CPU86017. CONCLUSION: Isop-induced arrhythmogenesis in MI heart was correlated mainly with a dispersion of depressed mRNA abundance in ventricle likely due to the consequence of PKA over-phosphorylation. A suppression of arrhythmia by Pro and CPU86017 resulted from a regression of the dispersion and depression of RyR2 and SERCA2.

关键词： myocardial infarction isoproterenol arrhythmia calcium 4-chlorobenzyltetrahydroberberine

Determination of Young's modulus by nanoindentation

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Science china(Technological Sciences) 2004年第4期47卷 398-408页

作者： MA Dejun1, Chung Wo Ong2, LIU Jianmin1 & HE Jiawen3.1. Surface Engineering Research Institute, CMES, Beijing 100072, china 2. Department of Applied Physics and Materials Research center, The Hong Kong Polytechnic University, Hong Kong, china 3. State Key Laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xian 710049, china 1. Surface Engineering Research Institute CMES 100072 Beijing China 2. Department of Applied Physics and Materials Research center The Hong Kong Polytechnic University Hong Kong China 3. State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong University 710049 Xi’an China

A methodology for determining Youngs modulus of materials by non-ideally sharp indentation has been developed. According to the principle of the same area-to-depth ratio, a non-ideally pyramidal indenter like a Berkovich one can be approximated by a non-ideally conical indenter with a spherical cap at the tip. By applying dimensional and finite element analysis to the non-ideally conical indentation, a set of approximate one-to-one relationships between the ratio of nominal hardness/reduced Youngs modulus and the ratio of elastic work/total work, which correspond to different tip bluntness, have been revealed. The nominal hardness is defined as the maximum indentation load divided by the cross-section area of the conical indenter specified at the maximum indentation depth. As a consequence, Youngs modulus can be determined from a nanoindentation test only using the maximum indentation load and depth, and the work done during loading and unloading processes. The new method for determining Youngs modulus is referred to as pure energy method. The validity of the method was examined by performing indentation tests on five materials. The experimental results and the standard reference values are in good agreement, indicating that the proposed pure energy method is a promising substitution for the most widely used analysis models at present.

关键词： Young's modulus, nanoindentation, nominal hardness, indentation work.