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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.{2. 2.Graduate University of chinese academy of sciences, Beijing 100039,{2. 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, 2. and 30 d after burying) and at five depths (0, 0.2. 0.5, 1 and 2.m). 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 2. and 30 burial days under dif-ferent burial depths. The degradation of chlorophyll a content appeared only at 2. 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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Synthesis of the Acetate of a New Phenolic Glycoside,Anacardoside,from Semecarpus anacardium and its Diastereomer

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chinese Chemical Letters 1998年第6期9卷 533-536页

作者： Yu Lan WANG Cheng He ZHOU Meng Shen CAI (institute of Chemical Metallurgy, chinese academy of sciences, Bejing 100080)( School of Pharmaceutical {2., Beijing Medical University, Beijing 100083) chinese Acad Sci Inst Chem Met Beijing 100080 Peoples R China Beijing Med Univ Sch Pharmaceut Sci Beijing 100083 Peoples R China

the acetate of a novel phenolic glycoside, 1-O-beta-D-glucopyranosyl-( 1-->6)-beta-D-glucopyranosyloxy-3-hydroxy-5-methylbenzene anacardoside, from the fruits of Semecarpus anacardium, and its diastereomer were first ... 详细信息

关键词： acetate of anacardoside diastereomer synthesis phenolic glycoside

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EXTENDED CASIMIR APPROACH TO CONTROLLED HAMILTONIAN SYSTEMS

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Journal of Systems Science & Complexity 2006年第2期19卷 211-218页

作者： Yuqian GUO Daizhan CHENG institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China.

In this paper, we first propose an extended Casimir method for energy-shaping. Then it is used to solve some control problems of Hamiltonian systems. To solve the Hoo control problem, the energy function of a Hamiltonian system is shaped to such a form that could be a candidate solution of HJI inequality. Next, the energy function is shaped as a candidate of control ISS-Lyapunov function, and then the input-to-state stabilization of port-controlled Hamiltonian systems is achieved. Some easily verifiable sufficient conditions are presented.

关键词： Casimir function Energy-shaping H∞ control Input-to-state stabilization.

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Suggestions for New Socialist Countryside Construction Based on Current Situations

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Asian Agricultural Research 2012年第8期4卷 56-59页

作者： YAN Shun-xi 1 ,WANG Xiao-lei 1 ,YAN Yong-lu 2.1. College of Mining Engineering,Hebei United University,Tangshan 063009,china 2. institute of Rural Economy,Hebei {2. of Social sciences,Shijiazhuang 050016,china

According to our field survey,we analyzed current situations and existing problems in the new socialist countryside construction of Hebei Province. Based on these,we put forward our suggestions: put the government and farmers in correct place; improve farmers' quality and educational level; implement the new socialist countryside construction under the guidance of overall rural plan and combining natural and economic conditions of rural areas; and ensure continuous and long-term work.

关键词： Rural culture New socialist countryside constructi

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THE DESIGN OF AN INTEGRATED SYSTEM FOR PREDICTING AND ANALYZING SOLDER JOINT SHAPE AND RELIABILITY INSMT

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 69-74页

作者： C. Q. Wang X. J. Zha C. Q. Zhang S. Q. Yang C. Z. Wang( 1)National Lab of Advanced Welding Technology, HIT, Harbin 150001, china 2.Shanghai institute of Metallurgy, {2. academy of Science, Shanghai 2.0050, china)

Solder joint reliability is one of critical problems detemining whether Sirface Mount Technology (SMT) can be used in the prohotion of important electronic products. Optimizing solder joint shape is one of effective ways to improve SMT solder joint *** this paper. based on the theorem of minimum potential energy, an energy model of 3 - D solder joint shape is established,and the forma- tion of solder joint is numerically simulated by Surface Ecolver program. On the basis of the prediction of SMT solder joint shape,the mechanical model of analyzing solder joint reliability is established. An elasto - plasto - creep mateial model and its mechanical constitutive equaton are established for SnPb solder alloy, and the stress/strain response of SMT solder joint under thermal cyclical loabing is ana- lyzed with nonlinear 3 - D FEM. The fatigue life of solder joint is predicted according to Coffin- Manson fatigue life model. An integrated system for Predicting and analyzing SMT solder joint shape and reliability(PSAR) is *** system can analyze efficiently SMT solder joint reliability with the variation of structural parameters in the joint and give the optimal structure.

关键词： SMT solder joiot relnddity solder joint shape,optimization

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Biogas charging and dissipating process and its accumulation in the Sebei gasfield,Qaidam Basin,china

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Science china Earth sciences 2008年第S1期51卷 36-44页

作者： JIN Qiang 1,CHENG FuQi 1,2.,SU AiGuo 3 ,ZHU GuangYou 3 ,WANG Li 1 &CAO Qian 1 1 china University of Petroleum,Dongying,Shandong 2.7061,china 2.Geological {2. of Shengli Oilfield,SINOPEC,Dongying,Shandong 2.7015,china 3 Petroleum Exploration and Development {2.,Petrochina,Beijing 100083,china china Univ Petr Shandong 257061 Peoples R China SINOPEC Geol Inst Shengli Oilfield Shandong 257015 Peoples R China Petrochina Petr Explorat & Dev Inst Beijing 100083 Peoples R China

The Sebei gasfield is the largest biogas accumulation found in china and many reservoirs and seal rocks superposed on a syndepositional anticline in *** biogas charging and dissipating process and its distribution have been a research focus for many *** authors suggest a diffusing and accumulating model for the biogas,as they find that the shallower the gas producer,the more methane in the biogas,and the lighter stable carbon isotope composition of *** on the diffusing model,diffused biogas is quantitatively estimated for each potential sandy reservoir in the gasfield,and the gas charging quantity for the sandy reservoir is also calculated by the diffused gas quantity plus gas reserve in-place.A ratio of diffusing quantity to charging quantity is postulated to describe biogas accumulating state in a sandy reservoir,if the ratio is less than 0.6,the reservoir forms a good gas-pool and high-production layer in the gasfield,which often occurs in the reservoirs deeper than 900 m;if the ratio is greater than 0.6,a few gas accumulated in the reservoir,which frequently exists in the reservoirs shallower than 900 ***,a biogas accumulation model is built up as lateral direct charging from gas source for the sands deeper than 900 m and indirect charging from lower gas-bearing sands by diffusion at depth shallower than 900 *** this charging and diffusion quantitative model,the authors conducted re-evaluation on each wildcat in the central area of the Qaidam Basin,and found many commercial biogas layers.

关键词： biogas charging and diffusing model relative dissipated quantity Qaidam Basin

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Sequence Stratigraphy and Relative Sea Level Changes in Sinian System of Yichang, Hubei Province

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Journal of Earth Science 1996年第1期15卷 29-37页

作者： Wang Ziqiang (Department of geology and Mineral Resources, china University of Geo{2., Beijing 100083) Gao Linzhi (institute of geology, chinese academy of Geological {2., Beijing 100037) Zhang Linghua Jiang Ganqing Zhang Chuanheng Yin Yong (Dep

The study on outcrop sequence stratigraphy of the Sinian section in the Yangtze Gorges an important step in the comprehensive stratigraphy for the Sinian stratotype. In this paper, the base of the Nantuo tillite is selected as the bottom boundary of the Sinian, and the top of the Baimatuo Member of the Dengying Formation is taken as the top boundary. The Sinian lasted from 740 the to 570 Ma. According to the features of sequence boundary facies and the parasequence sets, two supersequences are recognized in the Sinian with six sequences. In this paper, the authors discuss the correlation of those sequences. On the basis of the subsidence rate and the thickness of decompressed deposits, the authors discuss the mechanism of tectonic and sedimentation of the Dengying Formation and the features of high-frequency rhythms as well as the 3rd-order sequences in the Yangtze Gorges.

关键词： Sinian System sequence supersequence stacking parasequence set.

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Physical Diffusion and Electron-transfer Dynamics of Electroactive Solutes in Polymer Electrolytes Ⅰ. Effect of the Nature of Electroactive Solutes

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chinese Chemical Letters 1997年第10期8卷 825-828页

作者： Li Ming DING Hua Fang ZHOU Zhong SHI and Shao Jun DONG(Changchun institute of Applied Chemistry, chinese academy of sciences, Changchun 13002.) Changchun Inst. of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The diffusion coefficients(Dapp) and the heterogeneous electron-transfer rate constants(ks)for ferrocene and its seven derivatives in MPEG/LiClO4 electrolyte were determined by using steadystate voltammetry. The two parameters increase with increasing temperature, indicating Arrhenius behavior. The effects of the nature of electroactive solute molecules on Dapp, ks, and the half-wave potentials(E1/2. are discussed.

关键词： Nature Physical Diffusion and Electron-transfer Dynamics of Electroactive Solutes in Polymer Electrolytes Effect of the Nature of Electroactive Solutes

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Structure of reproductive apparatus of Gracilaria/Gracilariopsis lemaneiformis (Gracilariaceae,Rhodophyta)

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Science china(Life sciences) 2008年第12期51卷 1137-1143页

作者： XU Di1, ZHU JianYi2. HE Yang1, CHENG XiaoJie1, ZHANG WenYan1 & ZHANG XueCheng1 1 College of Life sciences, Ocean University of china, Qingdao 2.6003, china 2.Department of Biology, Changshu institute of Technology, Changshu 2.5500, china College of Life sciences Ocean University of China Qingdao 266003 China Department of Biology Changshu Institute of Technology Changshu 215500 China

Reproductive apparatus of Gracilaria/Gracilariopsis lemaneiformis collected from Qingdao city were studied with a light and a transmission electron microscope. The special superficial arrangement of spermatangium for this species was clearly observed, and the ultrastructure of spermatangial devel-opment revealed the similar cytodynamic pattern followed by all the Gracilariaceae members devel-oped from spermatangial mother cells to spermatangium. The female reproductive apparatus before fertilization was also observed and trichogyne was found protruding above the cortex, contrary to the earlier reports. Tetrasporangium was formed by an outer cortical cell and the tetraspores became spherical and expended after being released.

关键词： Gracilaria/Gracilariopsis lemaneiformis ultrastructure reproductive apparatus

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用壳聚糖亲和磁性微球纯化血浆凝血酶的研究

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生物化学与生物物理进展 2010年第4期37卷 433-440页

作者：李梅基李昭华胡建成董先智兰州大学生命科学学院兰州730000 中国科学院生物物理研究所北京100101

通过化学共沉淀法合成纳米粒子Fe3O4磁核,以壳聚糖为包裹材料包被自制的磁核,采用乳化交联法制备了具有核-壳结构的磁性高分子微球-壳聚糖磁性微球,并偶联肝素配基得到了一种新型亲和磁性微球,应用SEM、FT-IR、XRD等对微球的粒径、形貌... 详细信息

通过化学共沉淀法合成纳米粒子Fe3O4磁核,以壳聚糖为包裹材料包被自制的磁核,采用乳化交联法制备了具有核-壳结构的磁性高分子微球-壳聚糖磁性微球,并偶联肝素配基得到了一种新型亲和磁性微球,应用SEM、FT-IR、XRD等对微球的粒径、形貌、结构和磁响应性进行了表征.考察了该亲和磁性微球对凝血酶的分离纯化性能,并与传统的DEAE离子交换色谱法进行了比较.结果表明,所得亲和磁性微球具有较窄的粒径分布、形状规整,粒径在50nm左右.对凝血酶一步吸附纯化获得了比活为1879.71U/mg的酶,得率85%,纯化倍数11.057,而传统柱层析法得率为72.,纯化倍数仅为5.33.制备了壳聚糖亲和磁性微球,并将磁分离技术应用于凝血酶的分离纯化,得到了较好的效果,这将对于凝血酶的纯化及生产具有一定参考价值.

关键词：亲和磁性微球壳聚糖凝血酶磁分离纯化

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