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Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china 2. LASG, institute of Atmospheric Physics, {2. academy of Sciences, beijing 10002., china) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of Chemistry chinese {2. of Sciences, beijing 100080 china chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Over 2.x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1,2., GUO Qionglin~1**, HU Wei~1, WANG Yaping~1 and ZHU Zuoyan~1(1. State Key Laboratory of Freshwater Ecology and Biotechnology, institute of Hydrobiology, {2. academy of Sciences, Wuhan 430072. china 2. Graduate School of {2. academy of Sciences, beijing 100039, china) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]Graduate School of chinese academy of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1806 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 32. bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 32. bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

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,{2. 2. institute of Geographical Sciences and Natural Resources Research, chinese academy of Sciences, beijing 100101,{2. 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.

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 {2. of Sciences, beijing 100080, china 2.enter of Mass Spectrometry, institute of Chemistry, chinese {2. of Sciences, beijing 100080, china 3Graduate School of the chinese {2. of Sciences, {12. 100039, china institute of Microbiology Chinese Academy of SciencesBeijing 100080 China Graduate School of the chinese academy of Sciences{2. 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.

NUMERICAL SOLUTION OF THE UNSTEADYINCOMPRESSIBLE NAVIER-STOKES EQUATIONS ON THECURVILINEAR HALF-STAGGERED MESHNUMERICAL SOLUTION OF THE UNSTEADYINCOMPRESSIBLE NAVIER-STOKES EQUATIONS ON THECURVILINEAR HALF-STAGGERED MESH

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Journal of Computational Mathematics 2000年第5期18卷 521-540页

作者： Lan-chieh Huang (institute of Computational Mathematics and Scientific/Engineering computing, {2. academy of Sciences, beijing 100080, china) 中科院计算数学与科学工程计算所北京 100080

In this paper, the Crank-Nicholson + component-consistent pressure correction method for the numerical solution of the unsteady incompressible Navier-Stokes equation of [1] on the rectangular half-Staggered mesh has been extended to the curvilinear half-Staggered mesh. The discrete projection, both for the projection step in the solution procedure and for the related differential-algebraic equations, has been carefully studied and verified. It is proved that the proposed method is also unconditionally (in t) nonlinearly stable on the curvilinear mesh, provided the mesh is not too skewed. It is seen that for problems with an outflow boundary, the half-Staggered mesh is especially advantageous. Results of preliminary numerical experiments support these claims.

关键词： Unsteady incompressible Navier-Stokes equations Curvilinear half- staggered mesh Discrete projection.

High-temperature phases of pyrophyllite and their evolutionary characteristics

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chinese Science Bulletin 1997年第2期42卷 140-144页

作者： WANG Ling and ZHANG Zhenyu1. Changsha institute of Geotectonics, chinese {2. of Sciences, Changsha 410013, china 2. institute of Geology, chinese {2. of Sciences, beijing 10002., china Changsha institute of Ceotectonics Chinese Academy of Sciences Changsha China institute of Geology Chinese Academy of Sciences Beijing China

WITH the increase of heating temperature, phase of pyrophyllite will undergo a series of transformations. Former scholars have done some work in this respect; the temperature spans,however, were normally not more than 1150℃ and no relatively comprehensive results have been reported. Thus, the features of the phases from indoor temperature to melting point (1710℃±) for pyrophyllite and the entire evolutionary process of the phases are uncertain.

关键词： pyrophyllite high-temperature phase phase tranformation pyrophyllite anhydrite mullite cristobalite.

Quasirational dynamic system

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chinese Science Bulletin 2000年第14期45卷 1277-1279页

作者： SUN Daochun & YANG Lo1. Department of Mathematics, South china Normal University, Guangzhou 510631, china 2. {2. of Mathematics, academy of Mathematics and System Sciences, chinese academy of Sciences, beijing 100080, china Department of Mathematics South China Normal University Guangzhou China institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

Using the iterations of quasirational mappings, the theorems on dynamic system are generalized to the quasirational dynamic system. Some different results are also obtained.

关键词： quasirational mapping dynamic system covering surface.

Wet-chemical synthesis and characteristics of Au nanoshell

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Science china Chemistry 2005年第5期48卷 431-435页

作者： LIU Zhongxin1,2. SONG Hongwei1, YU Lixin1,2. YANG Linmei1,2.& PAN Guohui1,2.1. Key Laboratory of Excited State Physics, Changchun institute of Optics, Fine Mechanics and Physics, chinese {2. of Sciences, Changchun 130033, china 2. Graduate School of the chinese {2. of Sciences, beijing 100039, china 1. Key Laboratory of Excited State Physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese academy of Sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 2. nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 30℃ (5 W/cm2. irradiation area was 2.cm2.. This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.