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gasdynamic characteristics of toroidal shock and detonation wave converging

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 739-749页

作者： TENG Honghui1,2.& JIANG Zonglin2.1. key {3. of High Temperature {2. Dynamics, institute of Mechanics, chinese academy of Sci- ences, Beijing 100080, china 2. Graduate University of chinese academy of sciences, Beijing 10003., china key laboratory of High Temperature {2. Dynamics Institute of Mechanics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

关键词： converging, CCW relation, shock wave, detonation wave.

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2.3.& ZHAO DongMing4.1 College of Earth Science, Graduate University of chinese academy of sciences, Beijing 10004., china 2.{2. of Geodesy and Geophysics, chinese academy of sciences, Wuhan 4.0077, china 3.State key laboratory of Astronautic Dynamics, Xi’an 71004., china 4.Zhengzhou {2. of Surveying and Mapping, Zhengzhou 4.0052. china College of Earth Science Graduate University of Chinese Academy of Sciences Beijing China institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China State key laboratory of Astronautic Dynamics Xi’an China Zhengzhou institute of Surveying and Mapping Zhengzhou China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2.term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2.2.T), which is approximately equivalent to O(T2.. Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 2.0, and the models with regard to effect of J2.term have accuracies of 10-8 and the order can reach up to 2.0.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

Simulation study of phase retrieval for hard X-ray in-line phase contrast imaging

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 450-458页

作者： YU Bin1,2. PENG Xiang1,2. TIAN Jindong1, NIU Hanben1, DIAO Luhong3.& LI Hua3.1. key {3. of Optoelectronic Devices and Systems of Ministry of Education, {2. of Optoelec- tronics, Shenzhen University, Shenzhen 518060, china 2. State key {3. of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 3.0072.china 3. key {3. of Intelligent Information Processing, {2. of Computing Technology,{14., Beijing 100080,china key laboratory of Optoelectronic Devices and Systems of Ministry of Education Institute of Optoelectronics Shenzhen University Shenzhen China State key laboratory of Precision Measuring Technology and Instruments Tianjin University Tianjin China key laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China

Two algorithms for the phase retrieval of hard X-ray in-line phase contrast imaging are presented. One is referred to as Iterative Angular Spectrum Algorithm (IASA) and the other is a hybrid algorithm that combines IASA with TIE (transport of intensity equation). The calculations of the algorithms are based on free space propagation of the angular spectrum. The new approaches are demonstrated with numerical simulations. Comparisons with other phase retrieval algorithms are also performed. It is shown that the phase retrieval method combining the IASA and TIE is a promising technique for the application of hard X-ray phase contrast imaging.

关键词： X-ray optics, phase contrast imaging, phase retrieval, angular spectrum, hard X-ray.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2.REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 academy of Opto-Electronics,chinese academy of {4.,Beijing 100190,china 2.Graduate University of chinese academy of sciences,Beijing 10004.,china 3.lanzhou institute of Chemical Physics,chinese academy of {4.,lanzhou 73.000,china academy of Opto-Electronics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China lanzhou institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

^(13.)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State key laboratory of Environmental {2. Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-13.(13. Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 13. Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 13. Cs redistribution in a karst area of Southwest *** results indicated that the 13. Cs inventories of the surface soil on the slope studied were much lower than that of the local 13. Cs reference inventory and the 13. Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 13. Cs inventories was characterized by considerable *** high 13. Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 13. Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 13. *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 13. Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^13.Cs fallout, ^13.Cs inventory karst area runoff

Evaluation of 10 plant barcodes in Bryophyta (Mosses)

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Journal of Systematics and Evolution 2010年第1期48卷 36-46页

作者： 1,2.Yan LIU 3.Hai-Fei YAN 4.Tong CAO 3.Xue-Jun GE 1(institute of Applied Ecology,{3., Shenyang 110016,{2.) 2.Graduate University of the{3., Beijing 10004.,{2.) 3.key laboratory of Plant Resources Conservation and Sustainable Utilization, South{2. Botanical Garden,{3., Guangzhou 510650,{2.) 4.College of Life & Environment sciences, Shanghai Normal University, Shanghai 2.02.4.{2.) (institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (key laboratory of Plant Resources Conservation and Sustainable Utilization South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (College of Life & Environment sciences Shanghai Normal University Shanghai 200234 China)

DNA barcoding is a molecular tool that uses a standardized DNA region to identify *** preliminary study reported here is the first attempt to specifically focus on universality and attributes of candidate barcodes across a wide systematic range of *** tested eight previously proposed plant barcoding regions(atpF-atpH, ITS2. matK, psbK-psbI, rbcL, rpoB, rpoC1, and trnH-psbA) and two popular phylogenetic markers(rps4.and trnL-trnF of cpDNA) in 4. moss species and 9 liverwort species, representing half of the orders in moss *** ITS2. rbcL, rpoC1, rps4. trnH-psbA and trnL-trnF regions showed good universality, and therefore the efficacy of these loci as DNA barcodes was further evaluated in 3. mosses and 2.liverworts, each of which included two to three individuals per *** five loci, ***, rpoC1, rps4. trnH-psbA and trnL-trnF, were easy to amplify and sequence and showed significant inter-specific genetic variability, making them potentially useful DNA barcodes for *** best performing single loci were the rbcL and rpoC1 coding *** loci showed equivalent performance and combinations of them did not greatly increase their discrimination *** addition, phylogenies generated from each of the separate regions and multi-locus combinations by using best-fit and Kimura 2.parameter models were compared, but no significant difference was found.

关键词： Bryophyta DNA barcoding rbcL rpoC1 rps4 trnH-psbA trnL-trnF.

Transiently Expressed Short Hairpin RNA Targeting 12. kDa Protein of Tobacco Mosaic Virus Interferes with Virus Infection

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 22-28页

作者： Ming-Min ZHAO~(1,2.,De-Rong AN~(1*),Jian ZHAO~2.Guang-Hua HUANG~3.Zu-Hua HE~4.and Jiang-Ye CHEN~3. ~1 College of Plant Protection,Northwest Science and Technology University of Agriculture and Forestry,Yangling 712.00,china ~2.College of Agriculture,Yangtze University,Jingzhou 4.4.2.,china ~3.State {2. laboratory of Molecular Biology,institute of Biochemistry and Cell Biology,Shanghai institutes for Biological sciences, chinese academy of sciences,Shanghai 2.003.,china ~4.State {2. laboratory of Plant Molecular Genetics,institute of Plant Physiology and Ecology,Shanghai institutes for Biological sciences, chinese academy of sciences,Shanghai 2.003.0}china College of Plant Protection Northwest Science and Technology University of Agriculture and Forestry Yang ling 712100 China College of Agriculture Yangtze University Jingzhou 434025 China State key laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China State key laboratory of Plant Molecular Genetics Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

RNA-interference (RNAi) silences gene expression by'guiding mRNA degradation in asequence-specific *** interfering RNA (siRNA),an intermediate of the RNAi pathway,has beenshown to be very effective in inhibiting virus infection in mammalian cells and cultured plant ***,wereport that Agrobacterium tumefaciens-mediated transient expression of short hairpin RNA (shRNA) couldinhibit tobacco mosaic virus (TMV) RNA accumulation by targeting the gene encoding the replication-asso-ciated 12. kDa protein in intact plant *** results indicate that transiently expressed shRNA efficientlyinterfered with TMV *** interference observed is sequence-specific,and time-and *** expressed shRNA corresponding to the TMV 12. kDa protein gene did not inhibit cucumbermosaic virus (CMV),an unrelated *** order to interfere with TMV accumulation in tobaccoleaves,it is essential for the shRNA constructs to be infiltrated into the same leaves as TMV *** support the view that RNAi opens the door for novel therapeutic procedures against virus *** propose that a combination of the RNAi technique and Agrobacterium-mediated transient expressioncould be employed as a potent antiviral treatment in plants.

关键词： tobacco mosaic virus 12. kDa protein RNA interference short hairpin RNA

The role of reservoir mediums in natural oil cracking:Preliminary experimental results in a confined system

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chinese Science Bulletin 2010年第33期55卷 3787-3793页

作者： XIAO QiLin1,2.SUN YongGe1,3.& ZHANG YongDong1,2.1 State key {3. of Organic {2.,Guangzhou institute of {2.,chinese academy of sciences,Guangzhou 51064.,china 2.Graduate Schools,chinese academy of sciences,Beijing 10004.,china 3.institute of Environmental and Bio{2.(eBig),Zhejiang University,Hangzhou 3.002.,china State key laboratory of Organic {2. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate Schools Chinese Academy of Sciences Beijing China institute of Environmental and Biogeochemistry (eBig) Zhejiang University Hangzhou China

Large amounts of data regarding the influence of temperature and pressure on the thermal stability of crude oil have been pub-lished;however,the role of reservoir mediums has received little *** involving oil cracking in the presence of montmorillonite,illite,calcite,quartz and water were conducted in closed gold tubes to investigate the effects of these reservoir mediums on oil *** was done by screening variations in the chemical and stable carbon isotopic components of nC10+ and gasoline-range hydrocarbons(nC8-)present in various *** indicated that reservoir mediums have an active role in oil cracking under experimental *** concentrations of nC10+ in the cracked residues progressively decreased in systems containing oil+water+illite,oil+water+montmorillonite,oil+water,oil+water+quartz and oil+water+*** comparison with the system containing oil+water,our results indicated a retardation effect for oil cracking in systems in the presence of illite and montmorillonite,and an acceleration effect on oil destruction in systems in the presence of calcite and ***10+ became increasingly depleted in 13. in systems with oil+water+illite,oil+water+calcite,oil+water+montmorillonite,oil+water+ quartz and oil+*** obvious correlation was observed between concentrations and stable carbon isotopic components of nC6-nC8 and nC10+ in the individual *** discrepancies in chemical and stable carbon isotopic components of nC6-nC8 and nC10+ in the pyrolyzed residues highlighted the important role of reservoir mediums to control carbon-carbon cleavage of nC10+ and then the isomerization,cyclolization and aromatization reactions;as well as governing the occurrence and thermal destruction of nC6-nC8 under experimental *** research may have critical implications in reconstructing chemical kinetic models for natural oil cracking.

关键词：裂解作用实验条件密闭系统原油裂解水库介质天然同位素组成

Expression and purification of lipoprotein-associated phospholipase A2.a key enzyme involved in atherosclerosis

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Acta Pharmacologica Sinica 2006年第6期27卷 679-684页

作者： Fu-jun ZHANG~(2.4.Mao-jun CAI~3.Jing-kang SHEN~3.Yi-ping WANG~(2.5)2.State key {4. of Drug Research.3.Department of Medicinal Chemistry,Shanghai {2. of Materia Medica,Shanghai {2.s for Biological sciences,chinese academy of sciences.Shanghai 2.12.3.china 4.Graduate School of the{14..chinese academy of sciences,Shanghai 2.12.3.china State key laboratory of Drug Research Chinese Academy of Sciences Shanghai China Graduate School of the chinese academy of sciences Chinese Academy of Sciences Shanghai China Department of Medicinal Chemistry Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China

Aim:To express and purify lipoprotein-associated phospholipase A2.Lp-PLA2.,and to establish a screening model for Lp-PLA2.nhibitors using the expressed Lp-PLA2.Methods:We cloned the full-length cDNA of Lp-PLA2.from differentiatedTHP-I cells,and subcloned the cDNA into the baculovirus transfer *** addition,we introduced an N-terminal Kozak sequence for high-level translation initiation and a C-terminal sequence of 6 histidine residues forpurification,The fusion enzyme was expressed in Sf9 insect cells and purified byNi2.affinity *** Lp-PLA2.ctivity was measured us-ing[3.]PAF as a substrate,and we examined the enzyme activity of recombinantLp-PLA2.retreated with the known Lp-PLA2.nhibitor ***:Wesuccessfully cloned the full-length Lp-PLA2.ene from differentiated THP-1 *** fusion enzyme was expressed in Sf9 insect cells at a high level and purifiedefficiently through a 2.step *** recombinant Lp-PLA2.ctivity wasmeasured using[3.]PAF as a substrate,and proved to be enzymatically ***-PLA2.nhibitor SB{13.5{13.5 produced a good inhibition curve for inhibition ofrecombinant Lp-PLA2.ith an IC50of 57±1μmol/***:We expressed andpurified Lp-PLA2.t a high level in insect cell-baculovirus expression *** ratio was much greater than that obtained from human plasma and we estab-lished a screening model for Lp-PLA2.nhibitors using the expressed Lp-PLA2.

关键词： lipoprotein-associated phospholipase A2 atherosclerosis coronary heart diseases cloning baculovirus purification