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Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3, Shaoxiang XIONG2. Xiulan CHENG1, and Shijun QIAN1* 1institute of Microbiology, chinese academy of sciences, Beijing 100080, {2. 2.enter of Mass Spectrometry, institute of Chemistry, chinese academy of sciences, Beijing 100080, {2. 3Graduate School of the chinese academy of sciences, Beijing 100039, {2. institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the chinese academy of sciencesBeijing 100039 China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 4.7 and 4.9 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 4.6 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

Human remains and the environment of Early Pleistocene in the Nihewan Basin

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Science china Earth sciences 2004年第5期47卷 437-444页

作者： CAI Baoquan1 & LI Qiang2.1. Department of History, Xiamen University, Fujian 361005, china 2. institute of Vertebrate Palaeontology and Palaeoanthropology,{2., Beijing 10004., china Xiamen Univ Dept Hist Fujian 361005 Peoples R China chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China

A new Early Pleistocene Paleolithic site was found in July 2.01 in the Nihewan Ba-sin, Hebei Province. Totally 500 mammal specimens assigned to 2. species and 5 lithic artifacts were collected. The coexistence of Allophaiomys deucalion, Borsodia chinensis and Yangia tingi provides important evidence of chronology. On the basis of the comparison of mammalian fauna, the date of Paleolithic artifacts is probably earlier than 1.8 MaBP, possibly 2.0 MaBP. This is the earliest evidence of hominid activity found so far in North china. The hominid at that time in the Nihewan Basin lived in an environment of arid grasslands with scattered trees of temperate zone. This discovery is significant to the study of human origin and cultural development.

关键词： human remains, environment, Early Pleistocene, Nihewan.

Statistical distribution of nonlinear random wave height

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Science china Earth sciences 2006年第4期49卷 443-448页

作者： HOU Yijun1, GUO Peifang1,2. SONG Guiting1,2. SONG Jinbao1, YIN Baoshu1 & ZHAO Xixi1,2.1. institute of Oceanology, chinese academy of sciences, Qingdao 2.6071, {2. 2. Graduate University of the chinese academy of sciences, Beijing 100039, {2. 1. institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China 2. Graduate University of the chinese academy of sciences Beijing 100039 China

A statistical model of random wave is developed using Stokes wave theory of water wave dynamics. A new nonlinear probability distribution function of wave height is presented. The results indicate that wave steepness not only could be a parameter of the distribution function of wave height but also could reflect the degree of wave height distribution deviation from the Rayleigh distribution. The new wave height distribution overcomes the problem of Rayleigh distribution that the prediction of big wave is overestimated and the general wave is underestimated. The prediction of small probability wave height value of new distribution is also smaller than that of Rayleigh distribution. Wave height data taken from East china Normal University are used to verify the new distribution. The results in- dicate that the new distribution fits the measurements much better than the Rayleigh distribution.

关键词： Random ocean wave, nonlinearity, wave height distribution.

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 sciences,Beijing 100190,{4. 2.Graduate University of chinese academy of sciences,Beijing 10004.,{4. 3 Lanzhou institute of Chemical Physics,chinese academy of sciences,Lanzhou 730000,{4. 1. academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 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

Simulation of aerodynamic performance affected by vortex generators on blunt trailing-edge airfoils

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Science china(Technological sciences) 2010年第1期53卷 1-7页

作者： YANG Ke1,2.ZHANG Lei1,3 & XU JianZhong1,2.1 institute of Engineering Thermophysics,chinese {2. of sciences,Beijing 100190,{4. 2.Key Laboratory of Wind Energy Utilization,chinese {2. of sciences,Beijing 100190,{4. 3 Graduate School of chinese academy of sciences,Beijing 100190,{4. 1. institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Wind Energy Utilization Chinese Academy of Sciences Beijing 100190 China3. Graduate School of Chinese Academy of Sciences Beijing 100190 China

An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2.2.0 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angles of attack. Additionally, the pressure distribution on blended airfoil was analyzed by comparing to the airfoil without blend. The interaction of streamwise vortices induced by VGs with trailing vortex or separation vortex was considered, followed by the uncovery of how VGs can suppress the boundary layer separation.

关键词： vortex generators airfoil blunt trailing-edge

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. institute of Remote Sensing & GIS, Peking University, Beijing 100871, china 2. institute of Geographical sciences and Natural Resources Research,{4., Beijing 100101, china 1. institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

Single crystal β-Ga_2._3: Cr grown by floating zone technique and its optical properties

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Science china(Technological sciences) 2007年第1期50卷 51-56页

作者： ZHANG JunGang1, 2. LI Bin3, XIA ChangTai1, XU Jun1, DENG Qun4. XU XiaoDong1, WU Feng1, XU WuSheng4. SHI HongSheng4. PEI GuangQing1, 2.& WU YongQing1,2.1 Shanghai institute of Optics and Fine Mechanics, chinese academy of sciences, Shanghai 2.1800, china 2.Graduate School of the chinese academy of sciences, Beijing 100039, china 3 Shanghai institute of Applied Physics, chinese academy of sciences, Shanghai 2.1800, china 4.GE (china) Research and Development Center Co. Ltd., Shanghai 2.12.3, china 1. Shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China 3. Shanghai institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 4. GE (china) Research and Development Center Co. Ltd. Shanghai 201203 China

β-Ga2.3: Cr single crystals were grown by floating zone technique. Absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were obtained by the peak values of absorption spectra. The value 10Dq/B=2..14.manifests that in β-Ga2.3 crystals Cr3+ ions are influenced by low energy crystal field. After high temperature annealing in air, the Cr3+ intrinsic emission was enhanced and the green lumines-cence disappeared. The strong and broad 691 nm emission was obtained at 4.0 nm excitation due to the electron transition occurred from 4.2.to 4.2. The studies manifest that the β-Ga2.3 crystals have the potential application for tunable laser.

关键词： β-Ga2.3: Cr single crystals floating zone technique tunable laser spectrum.

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3,ZHAO Hong1,3,ZHANG Jichuan2.3 & XUE Zhaohong2.1. National Key Laboratory of Acoustics,institute of Acoustics,chinese {2. of sciences,Beijing 100080,{4. 2. institute of Chemistry,chinese {2. of sciences,Beijing 100080,{4. 3. Graduate University of chinese academy of sciences,Beijing 10004.,{4. National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100080 China institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate University of chinese academy of sciences Beijing 100049 China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.

Ambient noise near the sea-route

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2. LI ZhengLin1,3 & PENG ZhaoHui1 1 National Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Beijing 100190, {2. 2.institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002., {2. 3 NanHai Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Haikou 5702.6, {2. National Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China NanHai Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou 570206 China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships