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THE OPTIMAL GRAINSIZE COMPOSITION OF SUSPENDED SEDIMENT OF HYPERCONCENTRATED FLOW IN THE MIDDLE YELLOW RIVER

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International Journal of Sediment Research 1997年第3期 170-176页

作者： XU Jiongxin Professor, Institute of Geography, chinese Academy of sciences, {2. 100101,{3.

Hyperconcentrated flows play an important role in erosion and sediment yield processes in the Yellow River basin. Based on data from the tributaries of middle Yellow River, it has been found that there exists an optimal grainsize composition of suspended sediment, which leads to the highest values of suspended concentration of hyperconcentrated flow. The formation of this optimal grainsize composition is controlled by surface materials and the seasonally alternated wind and water processes in the drainage basin.

关键词： Hyperconcentrated flow Optimal grainsize composition, Sediment yield Middle Yellow River

Deep Sequencing-based Analysis of High Salinity Stress Response in Thellungiella root

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Deep Sequencing-based Analysis of High Salinity Stress Respo...

EXPERIMENTS OF SEA ICE SIMULATION

2.09整合植物生物学研讨会

作者： Yijun Zhou~(1,2.),Fei Gao~(1,2.,Genfa Zhang~2.and Jinchao Feng~1 1 College of Life and Environmental {3.,Minzu University of china,{2. 100081,china 2.College of Life Science,{2. Normal University,{2. 100875,china.

As a salt and cold tolerant relative of Arabidopsis,Thellungiella halophila has been used as a model organism for studies of plant abiotic *** the past years,large-scale screening of stress-related gene in transcriptional level was hindered by lack of Thellungiella GeneChip and genome sequence information,fortunately the newly

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Journal of Hydrodynamics 2005年第6期17卷 686-692页

作者： LIU Xi-ying State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics （LASG） Institute of Atmospheric Physics （IAP） Chinese Academy of Sciences Beijing 100029 China

As a substitute for the original displaced pole grids, a simple rotated spherical coordinate system was intro duced into the Community Sea Ice Model version 4（CSIM4）, which is a component of the Community Climate System Model（CCSM） of the American National Center of Atmospheric Researeh（NCAR）, to deal with the ＂pole problems＂. In the new coordinates, both the geographical North Pole and South Pole lie in the model equator and grid sizes near the polar region are more uniform. With reanalysis dataset of American National Centers for Environment Prediction （NCEP） and Levitus dataset without considering sub-mixed layer heat flux, the model was integrated for 100 years with thermodynamics *** involved only in the former 49 years and both dynamic and thermodynamic processes involved in the left time. Inner consistency of model results was checked with no contradiction found. The results of last 10 years＇ model output were analyzed and it is shown that the simulated sea ice seasonal variation is rational whereas sea ice extent in the Barcnts Sea in winter is larger than that of observation, Numerical experiment on influence of sub-mixed layer heat flux was also carried out and it is shown that the sub-mixed layer heat flux can modulate seasonal variation of sea ice greatly. As a model component, the sea ice model with rotated spherical coordinates was coupled with other models （the oceanic general cir culation model is the LASG/IAP Climate System Ocean Model （LICOM） with reduced grid, other models are components of NCAR CCSM2. forming a climate system model and its preliminary results were also given briefly.

关键词： sea ice numerical simulation climate system model

An Empirical Estimation of Effects of Priority Forestry Programs on Farmers’ Incomes in china

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chinese Forestry Science and Technology 2008年第1期7卷 1-12页

作者： LIU Can1 CHEN Hua2.LV Jinzhi1 LI Nannan3.XING Xiangjuan4 1. china National Forestry Economics and Development Research Center, beijing 100714, P. R. china 2. Department of Economics, Shandong University of Economics and Finance, Ji’nan 2.0014, P. R.china 3. College of Economics and Management, beijing Forestry University, beijing 100081, P. R. china 4. College of Management, Nanjing Audit University, Nanjing 2.1815, P.R. china

china has launched six Priority Forestry Programs (PFPs) since 1998, i.e. the Natural Forest Protection Program, the Cropland Conversion to Forest and Grassland Program, Sandification Control Program for the Vicinity of beijing & Tianjin , Wildlife Conservation and Nature Reserve Development Program, Forest Industrial Base Development Program and Shelterbelt Development Programs for regions such as Three North and the Yangtze River Catchments. The Government of{2. has made different policies for these PFPs, such as subsidies, low-interest loans and revenue offsets. Using a fixed-effect model and panel data from 2.3.3.households in 9 counties of Sichuan, Hebei, Shaanxi, and Jiangxi provinces, this paper studies effects of PFPs on farmers’ incomes. The empirical results indicate that the effects of PFPs on farmers’ incomes are mixed. Overall, the impact of Conversion of Cropland to Forestland and Grassland Program is significantly positive, whereas that of the Natural Forest Protection Program and the Sandification Control Program around beijing & Tianjin is negative. To a lesser extent, the Shelterbelt Development Programs have a positive impact. In the meantime, different effects of PFPs on farmers’ incomes are also mixed for different provinces and different households are also mixed.

关键词： Priority Forestry Programs (PFPs) farmers’incomes fixed-effect model panel data forest economics

PASTORAL HUSBANDRY AND CONSERVATION AND UTILIZATION OF RANGELAND RESOURCES IN XINJIANG,GHINA

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干旱区资源与环境 1993年第Z1期7卷 293-296页

作者： Shen Changjiang Commission for Integrated Survey of Natural Resources (CISNAR), the chinese Academy of sciences, {2. 100101, P. R. of{3.

1. Pastoral husbandry is the basis of animal husbandry in Xingjing Animal husbandry in Xingjing Uygur Autonomous Region is supported by the some57 million ha natural rangeland (Commission for Integrated Servey of Natural Resources(CISNAR), 1989). The rangeland provides feeds for the 3. million heads of grazing animals(48.698 million sheep units) in the region. Natural rangeland takes about 3.% of the

关键词： Pastoral Husbandry Rangeland Resources Resource Conservation and Utilization

Identification and tissue expression of four interleukin-7 mRNA transcripts in chinese tree shrew(Tupaia belangeri)

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Identification and tissue expression of four interleukin-7 m...

An Electron Density Model above the Sunspot from a Mapping of NOAA 72.0 at 17 GHz

“细胞活动生命活力”——中国细胞生物学学会全体会员代表大会暨第十二次学术大会

作者： Xiao-Hong Liu~(1,2.,Yu Fan~(1,2.,Yong-Gang Yao~1 1.Key Laboratory of Animal Models and Human Disease Mechanisms of the chinese Academy of {3. & Yunnan Province,Kunming Institute of Zoology,3.0}Jiaochang Donglu,Kunming,Yunnan 6502.3.{2. 2.graduate School of the chinese Academy of {3.,beijing 10003.,{2.

Interleukin-7(IL7) is a pleiotropic cytokine mat is actively involved in immune *** plays an important role in the development,survival and expansion of T cells,B cells,Dendritic cells and natural killer *** tree shrew,a small experimental animal with a close affinity to primate,has been proposed as an alternative experimental animal to primates in biomedical ***,there is a lack of basic knowledge about the immune system of tree *** this study,we characterized the expression pattern of IL7 gene in different tissues of chinese tree *** used reverse transcription polymerase chain reaction(RT-PCR) and rapid amplification of cDNA end(RACE) approaches to clone the entire IL7 gene in tree *** then quantified the expression profile of IL7 mRNA transcripts in eight tissues (including heart,liver,spleen,lung,kidney,intestine,skeletal muscle and brain) in 2. tree shrews using quantitative real-time PCR.A total of 6 mRNA transcripts were discerned from the cDNA samples from different *** canonical form of IL7 gene is 1817 bp in length and encodes 177 amino acids. Besides this transcript,we found that three transcripts,termed as IL7-svl,IL7-sv2.IL7-sv3.were highly expressed in all tissues except for *** IL7-sv3.had significantly high expression in skeletal *** relatively high expression level of IL7 mRNA in different tissues is in accordance with the immuno-regulation function of ***,the exact role of different IL7 mRNA transcripts remains to be determined.

关键词： interleukin-7 tree shrew mRNA transcript tissue expression

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chinese Journal of Astronomy and Astrophysics 2002年第3期2卷 287-292页

作者： Xing－FengYu Jin－XingYao NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 PurpleMountainObservatory ChineseAcademyofSciencesNanjing210008

The brightness temperature distribution of microwave emission in a solar active region generally shows a ring structure, with a dip at the centre. However, no dip was found in the Nobeyama Radioheliograph left handed circular polarization (LCP) image on 1992.August 18; instead, there was a peak. This is a completely LCP source with zero right-handed circular polarization (RCP). We examine this structure in terms of the joint effect of gyroresonance and bremsstrahlung mechanism with a raised electron density above the central part of the sunspot, and the commonly assumed temperature and vertical dipole magnetic field models. The raised electron density is found to be 1.4 × 1011 cm-3.at the chromosphere base.

关键词： Sun: activity - sunspots - Sun: radio radiation - Sun: chromosphere

Mitochondrial Genome Evolution in Early Land Plants

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Mitochondrial Genome Evolution in Early Land Plants

2.09整合植物生物学研讨会

作者： Jiayu Xue~(1,2.,Yang Liu~1,Bin Wang~(1,2.,Libo Li~1,Peng Cui~3.Jun Yu~3.and Yin-Long Qiu~(1*) 1 Department of Ecology & Evolutionary Biology,University of Michigan,Ann Arbor,MI 48109-1048, USA 2.School of Life {3.,Nanjing University,Nanjing 2.0093.china 3.{2. Genomics Institute,the chinese Academy of {3.,{2. 1013.8,china.

Plant mitochondrial genomes have been known for a long time to be highly unusual in both genome structure and sequence ***,only two early land plant(one liverwort and one moss)mitochondrial genomes have been sequenced...

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山区花卉的生态旅游价值

山地学报 2008年第S1期26卷 93-96页

作者：马培张丹中国科学院水利部成都山地灾害与环境研究所中国科学院研究生院

作为绿色消费的生态旅游已经迅速普及到全球,我国的生态旅游业也迅速发展起来,但在其开发中面临如何丰富、深化其内涵的问题。针对山区丰富的花卉资源花色斑斓、千姿百态、四季花开不断等特点,对其在发展生态旅游中的造景功能、审美价... 详细信息

作为绿色消费的生态旅游已经迅速普及到全球,我国的生态旅游业也迅速发展起来,但在其开发中面临如何丰富、深化其内涵的问题。针对山区丰富的花卉资源花色斑斓、千姿百态、四季花开不断等特点,对其在发展生态旅游中的造景功能、审美价值、历史文化价值、生态价值以及旅游品牌开发价值等方面进行了讨论。

关键词：花卉山区旅游价值