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Nonholonomic mapping theory of autoparallel motions in Riemann-Cartan space

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science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1707-1715页

作者： GUO YongXin1,LIU Chang2,WANG Yong3.LIU shiXing1 & CHANG Peng2 1 College of Physics,Liaoning university,shenyang 11003.,china 2 school of Aerospace Engineering,{3. Institute of Technology,{3. 110081,china 3.school of Basic Medical science,Guangdong Medical College,Dongguan 523.08,china 1. College of Physics Liaoning University Shenyang 110036 China2. School of Aerospace Engineering Beijing Institute of Technology Beijing 110081 China3. School of Basic Medical Science Guangdong Medical College Dongguan 523808 China

The method of nonholonomic mapping is utilized to construct a Riemann-Cartan space embedded into a known Riemann-Cartan space,which includes two special cases that a Weitzenbck space and a Riemann-Cartan space are respectively embedded into a Euclidean space and a Riemann *** means of this mapping theory,the nonholonomic corresponding relation between the autoparallels of two Riemman-Cartan spaces is *** particular,an autoparallel in a Riemann-Cartan space can be mapped into a geodesic line in a Riemann space and an autoparallel in Weitzenbck space be mapped into a geodesic line in Euclidean *** on the Lagrange-d'Alembert principle,the equations of motion for dynamical systems in Riemman-Cartan space should be autoparallel equations of the *** applications,the problem of autoparallel motion of spinless particles,Chaplygin's nonholonomic systems and a rigid body rotating with a fixed point are investigated in space with torsion.

关键词： nonholonomic mapping Riemann-Cartan space connection torsion autoparallel

Design, selection and Application of High Efficient Complex Alloys

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Journal of university of science and Technology beijing 2001年第3期8卷 167-170页

作者： Jianliang Zhang, Donghua Huang, Zongwang Zhang, Zhanhui Yan, Xuefei Li, Qingsong Huang Metallurgy school, university of science and Technology beijing,{3. No. 2.steelmaking Plant, shougang Group, beijing 100041, china beijing Univ sci & Technol Met Sch Beijing 100083 Peoples R China No 2.steelmaking Plant Shougang Grp Beijing 100041 Peoples R China

The design, selection and application principles of complex alloys according to the requirements of making low-alloy steels are discussed. The designed complex alloys containing calcium, barium, magnesium, strontium, rare earth elements, etc. should not only be able to deoxidize, desulphurize and refine liquid steel, but also alloy it. The application principles of alloys are as follows: using si-Mn or si-Mn-Al alloys for pre-deoxidizing, si-Al-Ba or si-Al-Ca-Ba alloys for final deoxidizing and si-Ca-Ba-Mg(sr) alloys for refining.

关键词： deoxidization desulphurization inclusion complex alloy

CO observations of massive star forming regions at different evolutionary phases

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science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2, XU Ye1,3. sHEN Zhiqiang1,3.& LI Jingjing1,2 1. shanghai Astronomical Observatory, Chinese Academy of sciences, shanghai 20003., china 2. Graduate school of the Chinese Academy of sciences, beijing 10003., china 3. Joint Institute for Galaxy and Cosmology, shanghai Astronomical Observatory and the university of science and Technology of china, shanghai 20003., china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Graduate school of the Chinese Academy of sciences Beijing 100034 China Joint Institute for Galaxy Cosmology Shanghai Astronomical Observatory the university of science Technology of china Shanghai 200030 China

The 12CO (J=1-0), 13.O (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai station of Purple Mountain Observatory. Of the observed 9 sources, 13.O cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2O masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAs 22566+5828 in the observing field of s152.s153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2O maser simulta- neously.

关键词： star formation cloud core outflow H2O maser

CJZ3.a Iomerizine derivative,modulates P-glycoprotein function in rat brain microvessel endothelial cells

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Acta Pharmacologica sinica 2006年第4期27卷 414-418页

作者： Bian-sheng JI~2 Ling HE~3.Xiao-qu LI~4 Guo-qing LIU~(3.5) ~2Institute of Pharmacy,Henan university,Kaifeng 475001.china ~3.epartment of Pharmacology,china Pharmaccutical university.Nanjing 210009,china:~4school of Life sciences,beijing Normal university,beijing 100875,china Institute of Pharmacy Henan University Kaifeng China Department of Pharmacology China Pharmaceutical University Nanjing China school of Life sciences Beijing Normal University Beijing China

Aim:To investigate the modulatory effect of CJZ3.a lomerizine derivative,onP-glycoprotein(P-gp)function in rat brain microvessel endothelial cells(RBMEC).Methods:RBMEC were isolated and cultured in Dulbecco's modified Eagle's me-dium/F12(1:1)medium,and the amount of intracellular rhodamine 123.Rh 123.wasdetermined using a fluorescence spectrophotometer to evaluate the modulatoryeffect of CJZ3.on P-gp ***:The accumulation of Rh 123.was poten-tiated in a concentration-dependent manner after incubation with CJZ3.for RBMEC,but not for human umbilical vein endothelial cells(HUVEC).CJZ3.caused theaccumulation of intracellular Rh123.in a time-dependent manner and significantlydecreased the effiux of Rh 123.from the *** inhibitory effect of CJZ3.on P-gpfunction was reversible and remained for 120 min after CJZ3.2.5 μmol/L)wasremoved from the ***:CJZ3.has a potent in vitro effect on theinhibition of P-gp function.

关键词： CJZ3 P-glycoprotein blood-brain barrier

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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science china earth sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2, YANG Guangming2, ZOU Huamin3. QU Jing1 & ZHAO Wenxia4 1. Graduate school, china university of {3.sciences, Wuhan 43.074, china 2. Test Center, china university of {3.sciences, Wuhan 43.074, china 3. Physics and Technology College, Wuhan university, Wuhan 43.072, china 4. Test Center, Zhongshan university, Guangzhou 510275, china china Univ geosci Grad Sch Wuhan 430074 Peoples R China china Univ geosci Test Ctr Wuhan 430074 Peoples R China Wuhan Univ Phys & Technol Coll Wuhan 430072 Peoples R China Zhongshan Univ Test Ctr Guangzhou 510275 Peoples R China

sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (sAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463.nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3. and Fd3., respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F413.. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Power functions with low uniformity on odd characteristic finite fields

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science china Mathematics 2010年第8期53卷 1931-1940页

作者： ZHA ZhengBang 1,3.& WANG XueLi 2 1 school of Mathematical sciences,Luoyang Normal university,Luoyang 471022,china 2 school of Mathematical sciences,south china Normal university,Guangzhou 51063.,china 3.state Key Laboratory of Information security,Graduate university of Chinese Academy of sciences,beijing 100049,china 1. school of Mathematical sciences Luoyang Normal University Luoyang 471022 China3. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China2. School of Mathematical Sciences South China Normal University Guangzhou 510631 China

In this paper,we give some new low differential uniformity of some power functions defined on finite fields with odd *** corollaries of the uniformity,we obtain two families of almost perfect nonlinear functions in GF... 详细信息

关键词： almost perfect nonlinear function differential uniform function finite field

Development of environmental monitoring satellite systems in china

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science china earth sciences 2010年第S1期53卷 1-7页

作者： LI GuoPing1 & CAO ChunXiang2 1 school of earth and space sciences,Peking university,{3. 100871,china 2.state Key Laboratory of Remote sensing science,Jointly sponsored by the Institute of Remote sensing Applications of Chinese Academy of sciences and {3. Normal university,{3. 100101,china 1. school of earth and space sciences Peking University Beijing 100871 China2. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

With the increase in global environmental problems,the necessity and urgency of remote sensing technology being applied to environmental monitoring has been widely recognized around the *** has launched the environment and disaster monitoring and forecasting small satellite constellation HJ-1A/B and the FY3.atmosphere and environmental satellite,but they still cannot fully satisfy requirements for environmental *** paper summarizes the current status of satellite environmental monitoring in china and the existing problems of inadequate load design and low data utilization efficiency,and discusses the demand for environmental monitoring *** on the development of foreign satellite systems for environmental monitoring,the future development and key tasks of the environmental monitoring satellite system in china is discussed,as are some related initiatives.

关键词： environmental satellite environmental monitoring global climate change specialty load satellite system

Characteristics of Joint Welded by Laser Welding of Aluminium-Lithium Alloy with Filler Wire

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稀有金属材料与工程 2011年第S4期40卷 138-141页

作者： Yang J1,2,Li X Y1,Gong s L2,Chen L2,Xu F2 1 school of Material science and Engineering,beijing university of Technology,beijing 100083.china 2.science and Technology on Power Beam Processes Laboratory,beijing Aeronautical Manufacturing Technology Research Institute,beijing 100024,china beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China beijing Univ Technol Sch Mat Sci & Engn Beijing 100083 Peoples R China

The characteristics of weld shape,microstructure,mechanical properties and defects of 5A90 Al-Li alloy joint by laser welding (LBW) and laser welding with filler wire (LWFW) were studied and *** results indicated that the microstructure of joint by LWFW was fine-grained layer and the equiaxed grain in most of seams,which were similar to the joint by *** with the joint by LBW,the microstructure of joint by LWFW tended to fine,and the range of the columnar crystals zone was prone to *** Microhardness of the joint by LWFW (92.57HV0.2) was lower than that by LBW (95.65HV0.2),but the uniformity was *** ultimate tensile strength of the joint by LWFW was lower than that by LBW slightly,which reached to 73.03. and 79.22% of the base metal ***,the elongation of the LWFW joint was higher than that of the LBW joint significantly,which reached to 3..65% and 20.3.% of the base metal *** microstructure and mechanical properties of 5A90 Al-Li alloy by LWFW were better than that by *** defects of joint were mainly forming defects which were caused by improper parameters and porosity inside the joint,which was caused by uncleaned surface and incomplete penetration.

关键词： Al-Li alloy laser beam welding (LBW) laser welding with filler wire (LWFW) weld shape microstructure mechani-cal properties defects

Monitoring Dynamic Change of Land Cover Based on sVM and satellite Images in Hanoi,Vietnam

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Wuhan university Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2, LIU Chuang1, 3.1. Institute of geographic sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, {3. 2. Graduate university of Chinese Academy of sciences, beijing 100049, {3. 3. College of resources science and Technology, beijing Normal university, beijing 100875, {3. Institute of geographic sciences and Natural resources Research Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of sciences Beijing China College of resources science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (sVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2000,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERs) in 2008 were used. six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2008. There were 12 63..54 hm2 cropland de-creased between 1993.and 2000,and 8 227.6 hm2 cropland de-creased between 2000 and 2008. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERs dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERs) support vector machine (sVM) change detection