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Formation and migration of space charge packet in low density polyethylene

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Science China(Technological Sciences) 2005年第3期48卷 354-360页

作者： ZHENG Feihu 1., ZHANG Yewen 1., GONG Bin 1., ZHU Jianwei 1.& wu Changshun 2 1. Pohl Institute of Solid State Physics, Tongji University, Shanghai 200092, China 2. China National Center for Quality Supervision and Test of Electric Ware and Cable, Shanghai 200093, China Pohl Institute of Solid State Physics Tongji University China National Center for Quality Supervision and Test of Electric Ware and Cable

Pressure wave propagation (PWP) method was utilized to observe the space charges packet-like behavior in sheet samples of low-density polyethylene (LDPE) under the relative low electric field. The experimental results show that space charge packets are always generated at the anode and move across the sample to the cathode regardless of the polarity of DC voltage. This paper discusses the migration of space charge packets at 30–40°C, the possible charge resource of space charge packets carriers and trap level of the space charge.

关键词： solid dielectric,low-density polyethylene,space charge packet,trap.

Therapeutic angiogenesis induced by human hepatocyte growth factor (HGF) gene in rat myocardial ischemia models

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Science Bulletin 2003年第3期48卷 273-276页

作者： wu Danli1., ZHANG Yourong2*, LAO Miaofen1. QIU Zhaohua1. HA Xiaoqin1.& wu Zuze (wu Cutse)1.1. Department of Experimental Hematology, Institute of Radiation Medi-cine, Beijing1.0850, China 2. General Hospital of the People抯 Liberation Army of China, Beijing 1.0853, China Department of Experimental Hematology Institute of Radiation Medicine Beijing 100850 China

In order to investigate the feasibility of myo-cardial ischemia gene therapy, we cloned human hepatocyte growth factor gene from human placenta cDNA library by the RT-PCR method. Recombination adenovirus Ad-HGF was constructed by the method of co-transfection and ho-mologous recombination of plasmids in 293 cells. Ad-HGF was amplified in 293 cells and purified through CsCl density gradient centrifugation. Ad-HGF could be expressed in rat primary myocardial cells and HGF secreted into the culture media, which was tested by ELISA. The distribution and persistence of adenovirus in rat were investigated by green fluorescence protein as a report gene. In vivo we found that intramyocardial administration of Ad-HGF could induce angiogenesis in rat myocardium after ligation of coronary artery. The results suggested that Ad-HGF was effective in vitro and in vivo, and the data for designing human trial of gene therapy—— mediated cardiac angiogenesis were pro-vided.

关键词： myocardial ischemia gene therapy recombination ade-novirus hepatocyte growth factor.

Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 20-25页

作者： Wang Geng 1.2 , Nie Baochi 3, Wang Lin 1.& wu Wei 1.1. School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 1.6024, China 2. Urban and Environmental School, Liaoning Normal University, Dalian 1.6029, China 3. Shenyang Buraue of Water Resources, Shenyang 1.001., China. School of Environmental and Biological Science and Technology Oalian University of Technology Oalian 116024 China Urban and Environmental School Uaoning Nonnal University Oalian 116029 China Shenyang Buraue of Water Resources Shenyang 110013 China

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

关键词： the middle and lower reaches of the Liaohe River ecological security assessment indicators system GIS spatial differences

Characteristics of rare earth elements in soils in Guizhou carbonate region

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Chinese Science Bulletin 1999年第S2期44卷 115-116页

作者： YAN Chongling~(1.2), HONG Yetang~1. WANG Shijie~1. FU Shunzhen~2, ZHU Keyong~2 and wu Shanqi~2 1. State Key Laboratory of Environmental Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 2. Guizhou Institute of Environmental Protection, Guiyang 550002, China State Key Laboratory of Environmental Geochemistry Chinese Academy of Sciences Guiyang 550002 China Guizhou Institute of Environmental Protection Guiyang 550002 China

IN recent years, rare earth element (REE) being used in agriculture has gained greater progress and madeus reach some common views. The centent of REE (especially soluble REE) in soils has significantcorrelation with that of REE plant absorbed from soil. Therefore, it is very necessary to clarify contentvariation and background values of REE (especially soluble REE ) from the angles of relation of supplyand demand between soil and plants, for reasonably using REE and formulating relevant health standardin the region, avoiding excessive using REE and taking up soil environmental capacity of REE to result insoil or water-body polluted and sometime for researching rock weathering, soil-forming process and soilclassification in the region. This note deals with characteristics of content and distribution of REE andsoluble REE in soils of Guizhou carbonate region.

关键词： rare earth element soil, Carbonate area, Guizhou.

Flooding 1.90s along the Yangtze River, has it concern of global warming?

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Journal of Geographical Sciences 2001年第1期11卷 43-52页

作者： GONG Dao-yi1. ZHU Jin-hong2, WANG Shao-wu2 (1. Key Laboratory of Environmental Change and Natural Disaster, Institute of Resources Science, Beijing Normal University, Beijing 1.0875, China 2. Department of Geophysics, Peking University, Beijing 1.0871. Key Laboratory of Environmental Change and Natural Disaster Institute of Resources Science Beijing Normal University Beijing China Department of Geophysics Peking University Beijing China

There were a series of severe floods along the middle to lower reaches of the Yangtze River (Changjiang River) in China during the 1.90s. The extensive summer (June, July and August) precipitation is mostly responsible for the flooding. The summer rainfall in the 1.80s and the 1.90s is much higher than that in the previous 3 decades. The means for 1.90–1.99 is +87.62 mm above normal, marked the 1.90s the wettest decade since the 1.50s. Six stations with a time span of 1.80–1.99 are selected to establish century-long rainfall series. This series also shows that the 1.90s is the wettest decade during the last 1.0 years. In the wettest 1. years, four occurred in the 1.90s (1.91. 1.96, 1.98 and 1.99). Both global and China’s temperature show there is a relative lower air temperature during the 1.60–1.70s, and a rapid warming in the 1.80–1.90s. Comparisons of rainfall between 1.60–1.79 and 1.80–1.99 show there are dramatic changes. In the cold period 1.60–1.79, the summer rainfall along the Yangtze River is 3.8 % to 4.7 % below the normal, during the warm period 1.80–1.99, over 8.4 % to 1..2 % of summer rainfall occurs. Over the whole eastern China, the summer rainfall shows opposite spatial patterns from the 1.60–1.70s to 1.80–1.90s. The consistent trend toward more rainfall with global warming is also presented by the greenhouse scenario modeling. A millennial Drought/flood Index for the middle to lower reaches of the Yangtze River showed that although the surplus summer rainfall in the 1.90s is the severest during the past 1.0 years, it is not outstanding in the context of past millennium. Power spectra of the Drought/flood Index show significant interdecadal periods at 33.3 and 1..8 years. Thus, both the natural interdecadal variations and the global warming may play important roles in the frequent floods witnessed during the last two decades.

关键词： summer rainfall Yangtze River global warming interdecadal variation

The improvement of RFID anti-collision algorithm

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The improvement of RFID anti-collision algorithm

风险投资、创始人与高管薪酬——多边代理视角

第24届中国控制与决策会议

作者： Jie. Zhao 1., Lining.wu 1.2 1. Hebei university, Baoding 071.00,China2. Hebei university, Baoding 071.00, China

Anti-collision algorithm is necessary to the recognition of lots of labels reading, this paper expounds the realization mechanisms of the anti-collision algorithm and two anti-collision algorithms, then puts forward a... 详细信息

关键词： RFID Anti-collision Aloha

来源： cnki会议评论

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管理科学学报 2017年第6期20卷 78-88页

作者：陈闯张岩吴晓晖厦门大学管理学院厦门361005 江西财经大学会计学院南昌330013

风险投资与创始人是新上市企业股东中对公司治理制度形成具有重要影响的两类股东.对于管理层薪酬制度的形成,这两类股东具有较强的治理动机与能力,同时存在不同的治理诉求.用多边代理理论视角,将这两类对新上市企业管理层薪酬制度具有... 详细信息

风险投资与创始人是新上市企业股东中对公司治理制度形成具有重要影响的两类股东.对于管理层薪酬制度的形成,这两类股东具有较强的治理动机与能力,同时存在不同的治理诉求.用多边代理理论视角,将这两类对新上市企业管理层薪酬制度具有不同利益导向的角色整合在同一框架之中,分析他们对于新上市企业薪酬制度的影响.分析与实证表明,风险投资的存在,会提高新上市企业管理层的整体薪酬水平,扩大管理层内部薪酬差距,并且提高管理层的薪酬敏感系数.与此相反,创始人的存在则会导致管理层薪酬偏低,并且抑制风险投资对管理层内部薪酬差距与薪酬敏感系数的影响.

关键词：多边代理理论风险投资创始人管理层薪酬新上市公司

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富硒花生的营养品质和抗氧化活性

中国食品学报 2017年第8期17卷 48-54页

作者：高林田侠米瑞芳胡小松吴继红中国农业大学食品科学与营养工程学院国家果蔬加工工程技术研究中心农业部果蔬加工重点开放实验室北京100083 青岛农业大学资源与环境学院山东青岛266109

以不同的富硒花生为原料,探究富硒花生的营养品质和粗蛋白提取物的抗氧化活性。结果表明,花生富硒量的变化没有显著影响其水分、蛋白、脂肪、多糖、氨基酸含量;在矿物质组成上,富硒花生(2.36 mg/kg)较非富硒花生(0.1. mg/kg)的铜(5.74~1...

以不同的富硒花生为原料,探究富硒花生的营养品质和粗蛋白提取物的抗氧化活性。结果表明,花生富硒量的变化没有显著影响其水分、蛋白、脂肪、多糖、氨基酸含量;在矿物质组成上,富硒花生(2.36 mg/kg)较非富硒花生(0.1. mg/kg)的铜(5.74~1..02 mg/kg)、锌(30.86~36.58 mg/kg)含量显著增加,铁(39.43~32.69 mg/kg)、钙(363.49~365.80 mg/kg)、镁(2 770.30~2 465.64 mg/kg)含量显著降低;不同的富硒花生的粗蛋白通过SDSPAGE在1..4~1.6.0 ku范围分离出1.个条带,且不同分子质量的蛋白或肽链的浓度有所差异。在相同的蛋白质浓度下,硒浓度的变化趋势与富硒花生粗蛋白提取物的抗氧化活性的变化趋势一致,Fe还原力最高增加7倍,羟基清除率最高达89%。

关键词：富硒花生氨基酸组成羟自由基顺磁共振自旋捕集技术铁还原力

Hausdorff centered measure of certain linear Cantor sets

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Progress in Natural Science:Materials International 2005年第4期 10-16页

作者： PENG Li 1.* and wu Min 2(1. Department of Mathematics, Hubei University, wuhan 430062, China 2. Department of Applied Mathematics, South China University of Technology, Guangzhou 51.640, China) Department of Mathematics Hubei University Wuhan 430062 China Department of Applied Mathematics South China Uni-versity of Technology Guangzhou 510640 China

In this paper, we study the Hausdorff centered measure of certain linear Cantor sets. We establish the relationship between the Hausdorff centered measure of this set and the maximum centered density of the corresponding self similar measure. From this relationship, the Hausdorff centered measure of certain sets is obtained. In particular, we consider the linear iterated function system consisting of three maps with the same contraction ratios. Under some technical restrictions, we determine the exact Hausdorff centered measure of its attractor.

关键词： Hausdorff centered measure packing measure Cantor set.