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Effects of sand burial on biomass, chlorophyll fluores-cence and extracellular polysaccharides of man-made cyanobacterial crusts under experimental conditions

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Science china(Life sciences) 2007年第4期50卷 530-534页

作者： WANG WeiBo1,2, YANG CuiYun1,2, TANG DongShan1,2, LI DunHai1, LIU YongDing1& HU ChunXiang1 1 State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, chinese academy of sciences, Wuhan 430072, china 2 graduate university of chinese academy of sciences, beijing 100039, china 1. State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China 2. graduate university of chinese academy of sciences Beijing 100039 China

Soil cyanobacterial crusts occur throughout the world, especially in the semiarid and arid regions. It always encounters sand burial, which is an important feature of mobile sand dunes. A greenhouse study was conducted to determine the effects of sand burial on biomass, chlorophyll fluorescence and extracellular polysaccharides of man-made cyanobacterial crusts in six periods of time (0, 5, 10, 15, 20 and 30 d after burying) and at five depths (0, 0.2, 0.5, 1 and 2cm). The results indicated that with the increase of the burial time and burial depth extracellular polysaccharides content and Fv/Fm decreased correspondingly and there were no significant differences between 20 and 30 burial days under dif-ferent burial depths. The degradation of chlorophyll a content appeared only at 20 and 30 burial days and there was also no significant difference between them under different burial depths. It was also observed a simultaneous decrease of the values of the Fv/Fm and the content of extracellular poly-saccharides happened in the crusted cyanobacterium Microcoleus vaginatus Gom. It may suggest that there exists a relationship between extracellular polysaccharides and recovery of the activity of pho-tosystem II (PS II) after rehydration.

关键词： Microcoleus vaginatus Gom. man-made cyanobacterial crusts sand burial biomass photosynthetic activity extracellular polysaccharides

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HPLC-APCI-MS Determination of Free Fatty Acids in Tibet Folk Medicine Lomatogonium rotatum with Fluorescence Detection and Mass Spectrometry Identification

HPLC-APCI-MS Determination of Free Fatty Acids in Tibet Folk...

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首届中国中西部地区色谱学术交流会暨仪器展览会

作者： Yulin Li, Xian’en Zhao, Jinmao You, Yourui Suo, Fengzu Hu, Guichen Chen ( Northwest Plateau Institute of Biology, chinese academy of sciences, Xining, 810001, PR china Department of Chemistry, Qufu Normal university, Qufu, 273165, PR china graduate university of chinese academy of sciences, beijing, 100039, PR china)

A simple and sensitive method for the determination of free fatty acids (FFAs) using acridone-9-ethyl-p-toluenesulfonate (AETS) as fluorescence derivatization reagent by high-performance liquid chromatography (HPLC) has been developed. Free fatty acid derivatives were separated on Eclipse XDB-Cs column with a good baseline resolution and detected with the fluorescence which excitation and emission wavelengths of derivatives were set at λex=404 and λem=440nm, respectively. Identification of 19 fatty acid derivatives was carried out by online post-column mass spectrometry with atmospheric pressure chemical ionization (APCI) source under positive-ion detection mode. 19 FFAs from the extract of Lomatogonium rotation are sensitively determined. The results indicate that the plant Lomatogonium rotatum enriches an abundance of FFAs and FFAs of higher contents mainly focus on that of even carbon atoms C14, C16 and C18. The validation of the method including linearity, repeatability, and detection limits was examined. Most linear correlation coefficients for fatty acid derivatives are >0.9989, and detection limits (at signal-to-noise of 3:1) are 12.3-43.7 fmol. The relative standard deviations (RSDs) of the peak areas and retention times for 19 FFAs standards are < 2.24 % and 0.45 %, respectively. The established method is rapid and reproducible for the separation determination of FFAs from the extract of Lomatogonium rotatum with satisfactory results.

关键词： HPLC-APCI-MS FFAs AETS fluorescence detection derivatization Lomatogonium rotatum

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基于CARTWHEEL构型的小卫星星座有效基线分析

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系统仿真学报 2009年第16期21卷 4938-4941页

作者：夏玉立雷宏黄瑶中国科学院电子学研究所北京100080 中国科学院研究生院北京100039

编队小卫星有效基线分析是编队小卫星SAR系统性能分析的关键,提出了针对Cartwheel编队构型的精确基线分析方法。将小卫星星座绕飞轨迹Hill方程与地球自转相结合,综合考虑两者的影响,精确的对Cartwheel构型星座有效基线进行仿真计算,并... 详细信息

编队小卫星有效基线分析是编队小卫星SAR系统性能分析的关键,提出了针对Cartwheel编队构型的精确基线分析方法。将小卫星星座绕飞轨迹Hill方程与地球自转相结合,综合考虑两者的影响,精确的对Cartwheel构型星座有效基线进行仿真计算,并且对星座在不同轨道位置的基线偏差进行了分析。

关键词：小卫星星座有效基线 Cartwheel编队构型 Hill方程地球自转

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基于DSP+FPGA的三缓存图像处理系统设计

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数据采集与处理 2010年第S1期25卷 84-86页

作者：安涛金钢中国科学院光电技术研究所成都610209 中国科学院研究生院北京100039

设计了一种基于DSP+FPGA结构的高性能图像处理系统,在系统驱动设计中针对图像复杂度增加带来的处理超时问题,设计了三缓存结构的图像处理驱动程序,该方案在使得图像处理超时时间累积达到一帧时发生丢帧。系统验证结果表明,图像处理出现... 详细信息

设计了一种基于DSP+FPGA结构的高性能图像处理系统,在系统驱动设计中针对图像复杂度增加带来的处理超时问题,设计了三缓存结构的图像处理驱动程序,该方案在使得图像处理超时时间累积达到一帧时发生丢帧。系统验证结果表明,图像处理出现超时情况下,该方法实现的驱动程序处理效率高于传统的乒乓方式。

关键词：图像处理驱动超时三缓存结构

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Effect of Aspergillus niger on weathering of phosphorite rock

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Acta Geochimica 2006年第S1期 171-172页

作者： Shu CHEN1 ,2, Congqiang LIU1, Bin LIAN1 1 State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china 2 graduate university of the chinese academy of sciences, beijing 100039, china

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Multiple equilibria of cross-equatorial Inertial jets

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Science china Earth sciences 2007年第1期50卷 153-160页

作者： CHAO JiPing1,2 & LIU Fei3,4 1 National Marine Environmental Forecasting Center, beijing 100081, china 2 The First Institute of Oceanography ,SOA, Qingdao 266060, china 3 Key Laboratory Regional Climate-Environment for Temperate East Asia, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 4 graduate university of chinese academy of sciences, beijing 100039, china 1. National Marine Environmental Forecasting Center Beijing 100081 China 2. The First Institute of Oceanography SOA Qingdao 266060 China 3. Key Laboratory Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 4. graduate university of chinese academy of sciences Beijing 100039 China

Based on the developed Anderson and Moore's theory about cross-equatorial inertial jets and a nonlinear equivalence shallow water model, new universal functions are determined by the characters of the vortical large-scale air flow (atmosphere) or ocean current (ocean) related to the jet, then the potential vorticity and energy conservation equations along the streamline in the cross-equatorial in-ertial jets can be obtained. Because the governing equations are nonlinear, some limited multiple equi-libria of cross-equatorial inertial jets may exist. According to the character of large-scale air flow or ocean current outside the jets, the existent criterion for multiple eqnilibria in cross-equatorial inertial jets is discussed, and two examples for multiple equilibia of nonlinear governing equations are given.

关键词： multiple equilibria cross-equatorial inertial jets the potential vorticity energy conservation.

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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 100039, 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 100830, 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.

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Common-View Time Transfer based on COMPASS GEO Satellite

Common-View Time Transfer based on COMPASS GEO Satellite

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第三届中国卫星导航学术年会

作者： KONG Yao 1,2,3,YANG Xu-hai 1,2,SUN Bao-qi 1,2, (1.National Time Service Centre,chinese academy of sciences,Xi′an 710600,china 2.Key Laboratory of Precise Navigation,Positioning and timing,National Time Service Center, chinese academy of sciences,Xi′an 710600,china 3.graduate university of chinese academy of sciences,beijing 100039,china)

The GPS common-view（CV）time transfer method was used by lots of timing laboratories for accurate time *** accuracy of GPS common-view is up to a few *** with GPS,The COMPASS system is at the experimental *** order to test the capability of Compass common-view,The experiment were carried out between Changchun station and Kashi Station in September in *** receivers were installed in stations and the receivers were also connected to Cs atomic *** the experiment,the COMPASS-GEO satellites are observed by the two *** data were processed as ***,the raw COMPASS observation data were preprocessed,including outliers deletion、cycle slip detection and ***,the propagation error was *** ionosphere delay was calculated by using the dual frequency data of the COMPASS *** Hopfield model was used to compute the troposphere ***, utilizing precise ephemeris and accurate antenna coordinate,the clock difference of the two receivers was calculated with common-view method by COMPASS GEO *** result shows that the accuracy of COMPASS common-view can reach to that of GPS common-view.

关键词： GPS common-view COMPASS ionospheric delay GEO

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Experimental Study On The Distribution Of Particles Concentration Of Gas-Solid Fluidized Bed With Disparately Sized Binary Particles

Experimental Study On The Distribution Of Particles Concentr...

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中国颗粒学会第六届学术年会暨海峡两岸颗粒技术研讨会

作者： Jiantao Cao~(1,2),Zhonghu Cheng~1,Yitian Fang~1,Yang Wang~1 (1.Institute of Coal Chemistry,chinese academy of sciences,Taiyuan,Shanxi 030001,china 2.graduate university of the chinese academy of sciences,beijing 100039,china)

＜正＞Experiments were carried out to study the concentration distribution of disparately sized binary particle in the jet region of a 1-m dia ＆ 8-m high semicircular jetting fluidized bed with a conical *** particles concentration was measured by the optical fiber probe system and *** fine particles were injected coaxially to simulate fines recycled into the jet high temperature region in an actual operating unit with different fine particles feed-in *** was found that the coarse particles concentration increases when the jet gas-velocity reaches to the certain *** distributor gas-velocity increasing results in the increasing of the time-averaged particles volume concentration in the jet *** annular gas-velocity increase causes the particles concentration to *** there is high fine concentration existing in the jet region of large jetting fluidized *** fine particles concentration in the jet region increases with the increasing of fine particles feed-in quantity,and the fine concentration increased toward the bed surface. When reaching to a certain bed height,the fine concentration begins to decrease.

关键词： Fluidized bed Particle concentration Binary particles Distinct size difference Jet

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2-D Frequency Spectrum Features and Error Analysis for Interferometric Passive Microwave Imager

2-D Frequency Spectrum Features and Error Analysis for Inter...

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IEEE 2007 International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless Communications(ISMAPE-2007)

作者： Pan Bei~(1,2)Wu Ji~1 (1.Center for Space Science and Applied Research,chinese academy of Science,P.O.Box 8701,beijing 100080, china 2.graduate university of chinese academy of sciences,beijing 100039,china

This paper introduces the basic concepts of Interferometric Passive Microwave Imager(Aperture Synthesis Interferometric Radiometers),and presents several features of 2-D frequency *** basis of those features,the directions and positions of baselines with errors can be identified approximately. And the effects caused by several systematic errors (antenna position error,baseline absence,amplitude error and phase error in channels,and antenna pattern error)on the reconstructed images,are analyzed particularly. The analyses in the paper can provide the evidences to identify the error types and sources in Interferometric Passive Microwave Imager,and can supply important references to design enhancement algorithms.

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