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Structures and physical properties of rigid polyurethane foams with water as the sole blowing agent

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Science china Chemistry 2006年第4期49卷 363-370页

作者： LI Xiaobin1,2, CAO Hongbin1 & ZHANG Yi1 1. Institute of Process Engineering, chinese academy of sciences, beijing 100080, china 2. graduate school of the chinese academy of sciences, beijing 100039, china 1. Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China 2. graduate school of the chinese academy of sciences Beijing 100039 China

Rigid polyurethane foams blown by varying water level were prepared in this study. The structures and physical properties of rigid polyurethane foams blown by water were measured with FT-IR, universal testing machine (Instron3365), scanning electron microscope (SEM) and differential scanning calorimeter (DSC). The results show that polyurea and polybiuret were the typical charac- teristics, and the cream time and gel time were shorter for the fully water blown rigid foams than that for the fully cyclopentane blown foams. The density of foam samples decreased from 45.0 kg/m3 to 27.4 kg/m3 with the increase of water level from 3 pph to 7 pph. Compressive strength exhibited the similar behavior with density. The average cell size of foam samples ranged from 241 μm to 356 μm with the increase of water level from 3 pph to 7 pph, respectively. At the same time, poorer dimen- sional stability was encountered with the increase of average cell size due to fast diffusion rate of CO2 out of the foam. The results of thermal analysis show that the glass transition temperature (Tg) shifted to a higher temperature with the increase of isocyanate level when more water was used as chemical blowing agent.

关键词： polyether polyol, polyurethane rigid foam, compressive strength, dimensional stability, cell size, glass transition temperature.

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, china 2Center of Mass Spectrometry, Institute of Chemistry, chinese academy of sciences, beijing 100080, china 3graduate school of the chinese academy of sciences, beijing 100039, china 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 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 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.

BIFURCATION OF THE NORTH EQUATORIAL CURRENT DERIVED FROM ALTIMETRY IN THE PACIFIC OCEAN

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Journal of Hydrodynamics 2006年第5期18卷 620-626页

作者： WANG Qing-ye HU Dun-xin Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school of the chinese academy of sciences Beijing 100039 China

The gridded （1/3°＊1/3°） altimetry data from October 1992 through December 2004 were analyzed to study the seasonal and interannual variabilities of the bifurcation of the North Equatorial Current （NEC） at the surface in the western North Pacific Ocean. Calculations show that on annual average the bifurcation occurs at about 13.4°N at the surface. The geostrophic flow derived from Sea Surface Height （SSH） data shows that the southernmost latitude of the NEC bifurcation at the surface is about 12.9°N in June and the northernmost latitude is about 14.1°N in December. Correlation analyses between the bifurcation latitude and the Southern Oscillation Index （SOl） suggest that the bifurcation latitude is highly correlated with the E1 Nino/Southern Oscillation （ENSO） events. During the E1 Nino years the bifurcation of the NEC takes place at higher latitudes and vice versa.

关键词： bifurcation of the North Equatorial Current altimetry data Pacific Ocean North Equatorial Current (NEC),E1 Nino/Southern Oscillation (ENSO) events

Theoretical critical value curve and driving force formation of ecological migration in the arid land

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chinese Science Bulletin 2006年第A01期51卷 196-203页

作者： ZHU Zi’an & ZHANG Xiaolei Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china The graduate school of the chinese academy of sciences, beijing 100039, china Xinjiang Uygur Autonomous Region Development and Reform Commission, Urumqi 830002, china chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Xinjiang Uygur Autonomous Reg Dev & Reform Commis Urumqi 830002 Peoples R China

干旱陆地的易碎的 eco 环境的特征确定它骚乱抵抗的能力更低。在干旱陆地的自然荒芜的绿洲在在宽 Gobi 沙漠散布的马赛克补丁。人口分发是极大地依赖于水资源。人口与驱散的分发，简单生产和生活被描绘风格，和贫穷和遥远。生态的迁居... 详细信息

干旱陆地的易碎的 eco 环境的特征确定它骚乱抵抗的能力更低。在干旱陆地的自然荒芜的绿洲在在宽 Gobi 沙漠散布的马赛克补丁。人口分发是极大地依赖于水资源。人口与驱散的分发，简单生产和生活被描绘风格，和贫穷和遥远。生态的迁居被执行的原因躺在生态的问题。生态的降级是生态的迁居的主要驱动力。然后，驱动力的力量取决于生态的降级的度。因此，是否执行生态的移植取决于生态的降级的程度。理论上，为在干旱陆地的精明的生态的移植的批评的值曲线通过生态学的相对问题的全面研究被提出，经济等等，在干旱陆地与生态的移植经验结合了，并且基于干旱环境的特征。在这篇文章，与这条曲线，理论研究和生态的迁居的一些实践从不做作的行为和生态的移植的驱动力形成的政府行为的观点被做了。它分析活跃驱动力(因素) 和否定力量(因素) ，并且指出预定和在干旱陆地实现生态的迁居的步骤。理论曲线表达某些创见和适用性，它为为实现生态的迁居工程评估生态的降级和理论底的度提供一个量的方法。

关键词：生态迁移临界值驱动力贫瘠地

Preparation and characterization of a novel adsorbent for removing lipophilic organic from water

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Science china Chemistry 2005年第6期48卷 600-604页

作者： LIU Huijuan1, DAI Ruihua1, QU Jiuhui1 & RU Jia1,2 1. State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china 2. graduate school of the chinese academy of sciences, beijing 100039, china 1. State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 100085 Beijing China 2. graduate school of the chinese academy of sciences 100039 Beijing China

A novel composite adsorbent containing a kind of lipid-triolein is studied. The ad-sorbent is prepared by embedding triolein into cellulose acetate (CA) sphere. The preparation method, the physical-chemical properties of the adsorbent and the removal efficiency of two or-ganochlorinated pesticides are studied. The adsorbent is stable in water and no triolein leaks into water for 465 h soaking. The adsorbent has high adsorption capacity for organochlorinated pes-ticides such as dieldrin and aldrin. The results suggest that triolein-containing adsorbent could serve as a good adsorbent for lipophilic organic pollutants. The adsorption rate for lipophilic pol-lutants is very fast and has relation with the logKow of the compounds.

关键词： triolein, cellulose acetate, adsorbent, lipophilic organic, drinking water.

Wind vector retrieval using dual polarization imagery of ASAR

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Progress in Natural Science:Materials International 2006年第11期16卷 1183-1187页

作者： SONG Guiting~ 1,2 , HOU Yijun~1** and QI Peng~1(1. Institute of Oceanology, chinese academy of sciences, Qingdao 266071, china 2. graduate school, chinese academy of sciences, beijing 100039, china) [a]Institute of Oceanology Chinese Academy of Science Qingdao China [b]graduate school Chinese Academy of Sciences Beijing China

A new algorithm for retrieving wind vector using dual polarization imagery of advanced synthetic aperture radar (ASAR) is developed and tested. Based on the combination of co-polarization and cross-polarization, this new algorithm effectively eliminates the 180° ambiguity which occurs when using single imagery of the ASAR to retrieve wind vector. This algorithm also solves the problem that the retrieval results will break down on very small spatial scales. The results retrieved from dual polarization imagery of ASAR show that the wind speed and direction are in agreement with the data from Quikscat and buoy measurements. The root mean square errors of wind direction and speed between the retrieved results and data from Quikscat are 2.21° and 0.53 m/s, respectively. Comparisons between the new method and the traditional method show that the new methods fit the buoy data and Quikscat data a little better than the traditional method in this image.

关键词： wind vector retrieval ASAR dual polarization.

Phylogeny of fireflies (Coleoptera: Lampyridae) inferred from mitochondrial 16S ribosomal DNA, with references to morphological and ethological traits

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Progress in Natural Science:Materials International 2006年第8期16卷 817-826页

作者： LI Xueyan, YANG Shuang, XIE Meng and LIANG Xingcai (Laboratory of Entomology, Kunming Institute of Zoology, chinese academy of sciences, Kunming 650223, china Key Laboratory of Cellular and Molecular Evolution, Kunming Institute of Zoology, chinese academy of sciences, Kunming 650223, china graduate school of the chinese academy of sciences, beijing 100039, china) [a]Laboratory of Entomology Kunming Institute of Zoology Chinese Academy of Sciences Kunming China [b]graduate school of the chinese academy of sciences Beijing China [c]Key Laboratory of Cellular and Molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming China

We sequenced partial mitochondrial 16S ribosomal DNA (16S rDNA) of 18 firefly species from Southwest of china. Combined with homologous sequences previously reported, phylogenetic trees including Japanese, Korean and chinese species were reconstructed by neighbor-joining, maximum parsimony and Bayesian methods. All reconstructions agree on most nodes of the trees. Monophyly of Lampyridae is not supported because Rhagophthalmus ohbai in Rhagophthalmidae is included within it. Lamprigera, a genus placed unreliably in Lampyrinae, shows a close relationship to Amydetinae. Monophyly of Luciolinae is not supported because Pristolycus sagulatus (Lampyrinae) is included within it. In the Luciolinae, monophyly of Curtos and Hotaria is well established, respectively, but both morphological and molecular data continue to indicate that Luciola is not monophyletic and its subdivision is indeed necessary. Within the Lampyrinae, both Pyrocoelia and Diaphanes are not monophyletic, but monophyly of Pyrocoelia + Diaphanes is well supported. Phylogeny of Diaphanes is discussed for the first time. Generic placement of a newly discovered species (Diaphanes pectinealis Li et Liang) sharing some characters of Pyrocoelia and Diaphanes challenges the delimitation of these two similar genera. With references to the firefly mating systems, we suggest that more emphases should be placed on those sexually selected characters such as antennal structure in taxonomy of Lampyridae.

关键词： Lampyridae mitochondrial 16S rDNA morphological and ethological traits phylogeny.

Myotoxic activity of a Gln-49 phospholipase A2 from Agkistrodon blomhoffii ussurensis snake venom

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Progress in Natural Science:Materials International 2006年第2期16卷 178-182页

作者： BAO Yongming, BU Pengcheng, YANG Jun, YANG Wei, JIA Peilin and AN Lijia (Department of Bioscience and Biotechnology, Dalian University of Technology, Dalian 116024, china Institute of Biophysics, chinese academy of sciences, beijing 100101, china graduate school of chinese academy of sciences, beijing 100039, china) [a]Department of Bioscience and Biotechnology Dalian University of Technology Dalian China [b]Institute of Biophysics Chinese Academy of Sciences Beijing China [c]graduate school of chinese academy of sciences Beijing China

A novel myotoxic protein phospholipase A2(PLA2), denoted as Gln49-PLA2, has been isolated from snake venom of Agkistrodon blomhoffii ussurensis, which has weak lethal effect and apparent anticoagulant activity, but lacks the PLA2 and hemorrha-genic activity. Gln49-PLA2 obviously increases of plasma creatine-kinase (CK) upon intramuscular injection in mice, suggesting that it may induce a dose-dependent myonecrosis. Histological studies also reveal morphological changes in mouse skeletal muscles, including extensive myonecrosis, hemorrhage and neutrophil infiltration in the treated animals. The myotoxic ability induced by Gln49-PLA2 can be partially inhibited by heparin.

关键词： snake venom phospholipase A2 Agkistrodon blomhoffii ussurensis myotoxic activity.

Possible Energy Network with polygeneration system and CCS for china

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中国科学：技术科学英文版 2010年第1期53卷 33-39页

作者： GAO Lin1,LI Sheng1,2,JIN HongGuang1 & LIN Hu1 1 Institute of Engineering Thermophysics,chinese academy of sciences,beijing 100190,china 2 graduate school of chinese academy of sciences,beijing 100039,china 1. Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Graduate School of Chinese Academy of Sciences Beijing 100039 China

On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2 with near zero energy penalties,and storing CO2 on sites,a new kind of Energy Network can integrate energy utilization,CO2 capture,transportation and storage ***-economic analysis of this solution focusing on Inner Mongolia and the Yangtze River Delta districts had been carried with comparison to the chain method for energy utilization and CO2 *** solution can save 21.5% of energy,and reduce 35% of total *** adoption of advanced polygeneration systems contributes 52.2% of the total saved costs,and the integration of energy utilization and CO2 sequestration in the Energy Network contributes 47.8%.From the aspect of CCS,the CO2 sequestration cost in the Energy Network can be as low as 12 $/t due to the lower energy penalties of capture in polygeneration systems and the combination of CO2 source and *** Energy Network exhibits attractive performance on energy saving,costs reduction for CCS,which may be a promising solution for sustainable development of china.

关键词： CO2 capture and storage Energy Network polygeneration system