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Effect of apple production base on regional water cycle in Weibei upland of the Loess Plateau

Journal of Geographical Sciences 2001年第2期11卷 239-243页

作者： HUANG Ming-bin~1, HE Fu-hong~2. YANG Xin-min~1, LI Yu-shan~1 (1. institute of Soil and Water Conservation, CAS, Yangling 712.00, china 2. Northwest Sci-tech University of Agriculture and Forestry, Yangling 712.00, china) institute of Soil and Water Conservation CAS Northwest Sci-tech University of Agriculture and Forestry

Weibei upland, located in southern part of the Loess Plateau, is a commercial apple production base in china. The enlargement of apple-planting area has a great impact on the regional water cycle. The effects of different land use on hydrological parameters are compared and studied in this paper. The main results are as follows (1) The initial and steady infiltration rates in apple orchard are higher than those in other land use types such as grassland, idle land and farmland. Their initial rates of infiltration are 0.82. cm/min, 0.2.5 cm/min, 0.534 cm/min and 0.586 cm/min in apple orchard, grassland, idle land and farmland respectively. Their steady infiltration rates are 0.45 cm/min, 0.038 cm/min, 0.191 cm/min and 0.155 cm/min respectively. (2. There is no runoff generated in plot of apple orchard in all 8 storm events in observed natural rainfalls, while runoff is generated in winter wheat plot, corn plot and alfalfa plot with runoff coefficients of 2.39%, 1.58% and 0.31% respectively. (3) The transpiration of apple trees is strong and thus soil moisture is gradually depleted. The average soil water contents in 3–9 m soil profile in Changwu plots with apple trees of 14 and 32.years in age are 11.77% and 11.59% and in Luochuan plots with those of 15 and 2. years in age are 11.7% and 11.59% respectively, which are nearly 9.0% of wilting moisture of Changwu soil and 8.6% of wilting moisture of Luochuan soil. The pathway of rainfall percolating to groundwater is hindered by dry soil profile.

关键词： Loess Plateau Weibei upland water cycle

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Integrin β4 mAb inhibited apoptosis induced by deprivation of growth factors in vascular endothelial cells

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Acta Pharmacologica Sinica 2004年第6期25卷 31-35页

作者： Ke-wen ZHAO, Qi-tao ZHAO, Shang-li ZHANG, Jun-ying MIAO2.institute of Developmental Biology, School of Life Science, Shandong University, Ji-nan 2.0100, china institute of Developmental Biology School of Life Science Shandong University Ji-nan 250100 Chin

AIM: To understand the mechanism by which anti-β4 integrin monoclonal antibody (mAb) inhibits apoptosis of vascular endothelial cells (VEC). METHODS: Viability was determined by counting the cells that attached to dishes after treatments. DNA fragmentation was analyzed by agarose gel electrophoresis and fluorescence microscopy. The intracellular content of cAMP was measured by radioimmunoassay (RIA). The levels of p53 and Ras expres- sions were analyzed by fluorescence microscopy combined with immunofluorescence under laser scanning confo- cal microscopy. RESULTS: After the cells were deprived of fibroblast growth factor (FGF) and serum were exposed to the mAb 5 mg/L for 2. h, the detachment and DNA fragmentation of these cells were suppressed. When cells were deprived of FGF and serum, the intracellular cAMP level and Ras protein content decreased (P<0.05), while the level of p53 protein expression increased (P<0.05). But in the presence of anti-β4 integrin mAb, VEC apoptosis was inhibited, and at the same time, the changes mentioned above were obviously blocked (P<0.05). CONCLUSION: Anti-4 integrin mAb inhibited apoptosis by affecting the level of cAMP, and blocking down- regulation of Ras protein and up-regulation of p53 protein in VEC.

关键词： integrin 4 monoclonal antibodies apoptosis umbilical veins vascular endothelium cyclic AMP protein p53 ras genes

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Introduction of pokeweed antiviral protein cDNA into Brassica napus and acquisition of transgenic plants resistant to viruses

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Chinese Science Bulletin 1999年第8期44卷 701-704页

作者： ZHANG Haiyan , TIAN Yingchuan , ZHOU Yihua , DANG Benyuan LAN Haiyan , SONG Guiying , WANG Lanlan , LIU Guizhen , ZHANG Lihua and CHEN Zhenghuainstitute of Genetics , Chinese Academy of Sciences , beijing 100101, {2. institute of Microbiology , Chinese Academy of Sciences , beijing 100080, {2. institute of Genetics Chinese Academy of Sciences Beijing China institute of Microbiology Chinese Academy of Sciences Beijing China

Using cotyledonary petioles as explants, the PAP cDNA controlled by wound-in-ducible promoter has been introduced into Brassica napus by coculture with Agrobacterium tumefaciens and laser microbeam puncture respectively. Regenerated plants resistant to gen-tamycin have been selected out. PCR amplification and Southern blotting analysis indicated that PAP cDNA together with wound-inducible promoter had been integrated into Brassica genome with transformation frequencies of 2.0% and 1.7% for two transformation methods respectively. The test of virus challenge showed that these transgenic Brassica plants were resistant in different degrees to mechanically inoculated TuMV.

关键词： pokeweed antiviral protein cDNA wound-inducible promoter Agrobacterium tumefaciens laser microbeam puncture.

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Performance of VBLAST Systems Based on Spatial Correlated MIMO Channels

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The Journal of china Universities of Posts and Telecommunications 2004年第z1期11卷 99-102页

作者： WANG Zhong-peng~1, QIU Zhong-yuan~2. WU Wei-ling~1 1.Information Enginnering School of beijing University of Posts and Telecommunications, beijing 100876, P.R. {2. 2.Information Engineering School, Liaoning institute of Technology, Liaoning 12.001, P.R. {2. Information Enginnering School of beijing University of Posts and Telecommunications Beijing 100876 P. R. China

Vertically-layered Bell Laboratories Layered Space-Time (VBLAST) is one of the most promising techniques for realizing high spectral efficiencies over wireless link. In previously published work, the performance of VBLAST has been primarily investigated in uncorrelated Rayleigh fading channels. However in real environments some correlation between antenna elements can be presented. In this paper, we study the impact of transmit correlation on the performance of VBLAST systems. Finally we provide simulation results demonstrating the impact of spatial fading correlation on the symbol error rate of VBLAST.

关键词： VBLAST correlated channel MIMO

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The influence of the surface heat fluxes of the Kuroshio key-area on meiyu rainfall in the Changjiang River region

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Acta Oceanologica Sinica 1991年第1期10卷 73-82页

作者： Ding Liangmo First institute of Oceanography,State Oceanic Administration,Qingdao,china First institute of Oceanography State Oceanic Administration Qingdao China China

On the basis, of the surface heat fluxes of the Kuroshio key-area (2.°-30°N, 12.°-30°E)in March andApril, the climatologicai influence of the Kuroshio heat fluxes on meiyu rainfall in the Changjiang River (Yangtse River) region are studied. The results are concluded as follows;the surface heat fluxes of the Kuroshio key-area have certain influence on meiyu rainfall in the Changjiang River region during June and July. The correctness rates for the five stations in the Changjing River region (i. e. Wuhan, Jiujiang, Anqing,Nanjing and Shanghai)are in the range of 9/2.-13/2.. The surface heat fluxes influence mainly on the homogeneous rainfall pattern,the correctness rates come to 7/10-8/10 for the lower valley of the Changjiang River. The estimation expression of the meiyu rainfall for Shanghai consisting of the surface heat flux and the sea surface temperature anomaly of the Kuroshio key area agrees well with the actual meiyu rainfall condition.

关键词： heat The influence of the surface heat fluxes of the Kuroshio key-area on meiyu rainfall in the Changjiang River region area

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CONVERGENCE PROPERTIES OF CONJUGATEGRADIENT METHODS WITH STRONG WOLFE LINESEARCH

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Systems Science and Mathematical Sciences 1998年第2期11卷 112-116页

作者： HAN Jiye LIU Guanghui YIN Hongxia(institute of Applied Mathematics, Academia Silica, beijing 100080, {2.)

In this paper, we investigate the convergence property of the conjugate gradientalgorithms which depend on the search directionsby using different choices for the scalar oh, where 9k is the gradient of f at ac. Undersome assumptions which are slightly weaker than those in [1], we prove a global convergenceresult which allows ac to be set in a wider range than that in [1].

关键词： Conjugate gradient algorithms global convergence) unconstrained optimization.

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抛罩-展开期间航天器太阳电池阵温度场的数值模拟

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太阳能学报 2002年第6期23卷 763-769页

作者：杨卫华程惠尔李瑞祥王治易上海交通大学动力与能源工程学院上海200030 上海航天局第805研究所上海201108

将太阳电池板中发生的辐射传导复合传热过程等效为一个无内热源的三维瞬态热传导问题。根据实测数据得出太阳电池板的三维等效导热系数。针对任意两相邻电池板表面间的热辐射交换规律 ,构造适用于这两个表面内节点温度的离散方程系数... 详细信息

将太阳电池板中发生的辐射传导复合传热过程等效为一个无内热源的三维瞬态热传导问题。根据实测数据得出太阳电池板的三维等效导热系数。针对任意两相邻电池板表面间的热辐射交换规律 ,构造适用于这两个表面内节点温度的离散方程系数。研究折叠状太阳电池阵边界节点的热特点时 ,仔细考虑了地球红外辐照、太阳辐射加热、航天器舱体几何遮挡、深冷环境散热、飞行轨道高度及航天器在太阳地球系中不同位置等造成的影响。采用SIP算法 ,对离散方程进行了求解。比较了考虑和不考虑地球红外辐射对电池阵温度分布的影响。

关键词：数值模拟航天器折叠状电池阵数值分析温度场太阳能电池

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Effects of Terracing and Agroforestry on Soil and Water Loss in Hilly Areas of the Sichuan Basin, china

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Journal of Mountain Science 2008年第3期5卷 241-248页

作者： J.H. ZHANG Z.A. SU G.C. LIU Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences 610041 China institute of Mountain Hazards and Environment Chinese Academy of Sciences ＆Ministry of Water Conservancy Chengdu 610041 China The Graduate School of the Chinese Academy of Sciences Beijing 100049 China

Soil erosion in hilly areas of the Sichuan Basin is a serious concern over sustainable crop production and sound ecosystem. A 3-year experiment was conducted using the method of runoff plots to examine the effects of terracing and agroforestry in farmland systems on soil and water conservation of slope fields in the hilly areas in Jianyang County, Sichuan Province, Southwestern china. A power function (Y = aXb) can statistically describe the relationship between water runoff (Y) and rainfall (X). The regression equation for the treatment of sloping terraces with crops (Plot 2. is remarkably different from that for the treatment of sloping terraces with grasses and trees (Plot 1) and the conventional up- and down-slope crop system (Plot 3) regarding equation coefficients, while regression equations are similar between Plot 1 and Plot 3. Water runoff amount and runoff coefficient of slope fields increased by 2..5～41.0 % and 2..5～69.7 % respectively, compared to those of sloping terraces, suggesting that terracing notably reduced the water runoff in the field. In the case of sloping terraces, lower amount of water runoff was observed on sloping terraces with crops than on sloping terraces with grasses and trees. Sediment yields on the slope fields in the normal year of rainfall distribution were notably higher (34.41～331.67 % and 37.06～403.44 % for Plot 1 and Plot 2. respectively) than those on sloping terraces, implying that terracing also plays a significant role in the reduction in soil erosion. It is suggested that terracing with crops is significantly effective for soil and water conservation in cultivatedfarmland, while the conventional practice of up- and down- slope cultivation creates high rates of water runoff and soil sediment transport. Terracing with grasses and fruit trees shows a less reduction in water runoff than terracing with crops, which was observed in the 3-year experiments.

关键词： Agroforestry sediment transport runoff sloping terrace soil and water conservation

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Distribution characteristics of zooplankton biomass in the East china Sea

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Acta Oceanologica Sinica 2004年第2期23卷 337-346页

作者： XUZhaoli CHAOMin CHENYaqu EastchinaSeaFisheriesResearchinstitute ChineseAcademyofFisheriesSciencesShanghai200090China KeyandOpenLaboratoryofMarineandEstuarineFisheriesofMinistryofAgricultureofchina Shanghai200090China

On the basis of the data of oceanographic survey in the East china Sea in four seasons during 1997-2.00 (2.°30'~33°00'N, 118°30'-12.°E), the variation of total biomass and diet biomass of zooplankton and their spatial-temporal distribution and relationship with the fishing ground of Engraulis japonicus are approached and analyzed. The results show that the average biomass is 65.32.mg/m3 in four seasons, autumn (86.18 mg/m3) being greater than summer (69.18 mg/m3) greater than spring (55.67 mg/m3) greater than winter (50.33 mg/m3). The average value of diet zooplankton biomass is 40.9 mg/m3. The trends of horizontal distribution both in the total biomass and the diet biomass of zooplankton are similar. The high biomass region (2.0-500 mg/m3) is very limited, only accounting for 1% of the investigation area. Seasonal variation of the biomass is very remarkable in the west and north parts of East china Sea coastal waters ( 2.°30'N,12.°E). The horizontal distribution of diet zooplankton depends on the abundance distribution of crustacean. The distribution of diet zooplankton is related to the fishing ground of Engraulis japonicus and the high-density area of young fish and larval. In spring, the central fishing ground of Engraulis japonicus (>100 kg/h) and the high-density area of young fish and larval (>100 individuals per net) are located at the same place of high-density (100-2.0 mg/m3)area of diet zooplankton in the middle-southern part of East china Sea or the edge of its waters.

关键词： zooplankton total biomass diet biomass East china Sea fishing ground of Engraulis japonicus

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SEEPAGE ABILITY OF HIGH-PRESSURE HOT COMPOSITE FOAM IN POROUS MEDIA

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Journal of Hydrodynamics 2010年第1期22卷 90-95页

作者： WANG Ke-liang LIANGShou-cheng YUAN Xin-qiang CHEN Jin-feng The Key Laboratory of Enhanced Oil and Gas Recovery of the Ministry of Education Daqing Petroleum Institute Daqing 163318 China College of Civil and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China The Second Oil Production Company of Daqing Oilfield Company Ltd. Daqing 163414 China

The technology of hot composite foam displacement refers to the injection of high-temperature flue gas and foaming and stabilizing agent into wells with a certain concentration, and after meeting the formation water, a composite foam system is formed in the reservoir. This foam displacement technology involves thermal function and so is related to nitrogen, carbon dioxide and foam flooding characteristics. After analyzing seepage flow law of hot composite foam system, seepage flow experiment of composite foam under high pressure was conducted, and seepage flow ability of hot composite foam in porous media was investigated. In the experiment, surfactant HY-3 was chosen as the foaming agent and hot flue gas was chosen as the foaming gas, and high-pressure hot foaming apparatus was employed in experiments. The experimental results indicate that the surfactant HY-3 could form stable foam in porous media, and the foam has strong ability of plugging. It is concluded that the sealing performance of foam is improved with increasing permeability and resistance coefficient and with incresing injection rate and foam strength. After foam injection, sealing characteristics of heterogeneous cores is better than that of homogeneous cores. The foam pressure has a process of transmission in porous media. In this process, with the increase of injection volume, pressure from the inlet to the outlet increases gradually, which indicates that stable foam has been formed inside the core.

关键词： composite foam surfactant HY-3 seepage flow under high pressure porous media

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