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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 26607., china 2. graduate school, chinese academy of sciences, beijing 100039, china) Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school Chinese Academy of Sciences Beijing 100039 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) Laboratory of Entomology Kunming Institute of Zoology chinese academy of sciences Kunming 650223 China graduate school of the chinese academy of sciences Beijing 100039 China Key Laboratory of Cellular and Molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 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.

Antisense expression of a rice cellular apoptosis susceptibility gene (OsCAS} alters the height of transgenic rice

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Progress in Natural Science:Materials International 2007年第1期17卷 39-43页

作者： XU Chunxiao and HE Chaozu ( National Key Laboratory of Plant Genomics, Institute of Microbiology, chinese academy of sciences, beijing 100080, china graduate University of chinese academy of sciences, beijing 100039, china Shenzhen Laboratory of Superhybrid Rice Research, graduate school at Shenzhen, Tsinghua University, Shenzhen 518055, china) National Key Laboratory of Plant Genomics Institute of Microbiology Chinese Academy of Sciences Beijing 100080 China graduate University Chinese Academy of Sciences Beijing 100039 China Shenzhen Laboratory of Superhybrid Rice Research Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China

Cellular apoptosis susceptibility (CAS) gene plays important roles in mitosis, development and export of importin a from the nucleus, but its function in plant is unknown. In this study, a rice CAS ortholog (OsCAS), which encodes a predicted protein of 983 amino acids with 62% similarity to human CAS, was identified. DNA gel blot analysis revealed a single copy of OsCAS in the rice genome. A 97. bp fragment at the 3' end of OsCAS cDNA was cloned from rice cDNA library and transferred into rice in the antisense direction under the control of CaMV 35S promoter via Agrobacterium-mediated transformation method, 105 transgenic lines were obtained. Expression of OsCAS was suppressed in the antisense transgenic lines as revealed by semi-quantitative RT-PCR. The antisense transgenic lines showed dwarf phenotypes. The results indicated that OsCAS was involved in culm development of rice.

关键词： antisense dwarf ortholog OsCAS rice.

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, beijing 100049 2 graduate school of chinese academy of sciences, beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school of chinese academy of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 35 AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Applications of URANS on predicting unsteady turbulent separated flows

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Acta Mechanica Sinica 2009年第3期25卷 319-324页

作者： Jinglei Xu Huiyang Ma Department of Physics, graduate University of the chinese academy of sciences, 100049 beijing, china Department of Physics Graduate University of the Chinese Academy of Sciences Beijing China

Accurate prediction of unsteady separated turbulent flows remains one of the toughest tasks and a practi cal challenge for turbulence modeling. In this paper, a 2D flow past a circular cylinder at Reynolds number 3,900 is numerically investigated by using the technique of unsteady RANS （URANS）. Some typical linear and nonlinear eddy viscosity turbulence models （LEVM and NLEVM） and a quadratic explicit algebraic stress model （EASM） are evaluated. Numerical results have shown that a high-performance cubic NLEVM, such as CLS, are superior to the others in simulating turbulent separated flows with unsteady vortex shedding.

关键词： URANS Nonlinear eddy viscosity turbulencemodel ,Separated flows Circular cylinder

Daily variation of carbon flux in soils of Populus euphratica forests in the middle and lower reaches of the Tarim River

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Progress in Natural Science:Materials International 2007年第5期17卷 584-590页

作者： Huang Xiang , Chen Yaning , Li Weihong , Ma Jianxin and Chen Yapeng (Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china graduate University, chinese academy of sciences, beijing 100039, china) Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China graduate University Chinese Academy of Sciences Beijing 100039 China

In order to lucubrate the daily variation of respiration in soils of Populus euphratica forests and analyze its relationship with environmental factors in the middle and lower reaches of the Tarim River, the LI-8100 instrument of soil CO2 flux system was used to measure the parameters of soil carbon flux and air temperature 10 cm above ground surface along the profiles of Usyman, Archy River, Yengisu and Karday, and the relationships between the soil carbon flux and the soil moisture content were analyzed. The nonlinear regression analysis was carried out with the software SPSS13.0. We observed that: (1) soil respiration began to be restrained when the air temperature was up to 30℃10 cm above the ground surface; (2) the rates of soil respiration under the forests of Populus euphratica were significantly different at various moisture contents, the soil carbon flux was high along the Usyman profile, which has a high soil moisture content, and it was low along the profiles of Archy River, Yengisu and Karday, which has a low soil moisture content; (3) the exponential model can be used to explain the relationship between soil respiration and air temperature 10 cm above the ground surface. The average Q10 values along the profiles of Usyman, Archy River, Yengisu and Karday are 0. 61, 0.16, 0. 22 and 0. 35 respectively, much lower than the average of the world; (4) there is a positive correlation between the soil carbon flux and the soil moisture content.

关键词： Populus euphratica soil carbon flux air temperature 10 cm above ground surface soil moisture content the Tarim River.

Comment on “Evolution model of the earth's limited expanding” from comparative planetology

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chinese Science Bulletin 2001年第17期46卷 1495-1496页

作者： SHI Yaolingraduate school, University of Science and Technology of china, chinese academy of sciences, beijing 100039, china graduate school University of Science and Technology of China Chinese Academy of Sciences Beijing China

In the article 'Evolution Model of the Earth’s Limited Expanding' published in Volume 45 Number (4) of chinese Science Bulletin[1], the author suggests that the earth expands according to a law R(t) = R0+A(1 -exp(β(t-ts))) (remark: this formula was mistakenly printed as R(t) = R0 + Aexp(β(t-ts)) in the and formula (12) of the text of ref. [1]). According to ref. [1], the earth was formed 4.6 billion years ago. After 0.3 billion years from its birth (ts), it started expansion from an initial radius R0 of 4651 km, and may reach a final maximum radius of R0+A = 6511 km. In the 4.6 billion years history, the radius of the earch has increased by 17.0 km, or the density decreased from 14200 km/m3 (2.57.times the present density) to 5520 kg/m3 within the latest 4.3 billion years.

关键词： from comparative planetology Evolution model of the earth’s limited expanding

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 {7. of chinese academy of sciences, beijing 100039, china) 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 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 Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China graduate school of chinese academy of sciences Beijing 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