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金沙江向家坝库区泥石流发育状况及其沟谷形态的非线性特征

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山地学报 2001年第1期19卷 29-32页

作者：李俊才胡卸文成都理工学院!四川成都610059 西南交通大学土木工程学院!四川成都610031

通过对金沙江向家坝库区长约 15 0km范围内的 5 5条泥石流沟发育状况统计显示 ,自库首至库尾 ,泥石流沟的数目、发育密度及规模均呈逐渐增强趋势。同时泥石流沟的流域面积、主沟长度及纵坡平均坡降均存在明显的分形特征 ,它们与沟道数... 详细信息

通过对金沙江向家坝库区长约 15 0km范围内的 5 5条泥石流沟发育状况统计显示 ,自库首至库尾 ,泥石流沟的数目、发育密度及规模均呈逐渐增强趋势。同时泥石流沟的流域面积、主沟长度及纵坡平均坡降均存在明显的分形特征 ,它们与沟道数目之间有良好的非线性关系 ,并在一定程度上揭示了这些泥石流沟谷形态演变的非均匀性和自相似性。

关键词：泥石流沟谷形态演变

Low-complexity distributed differential spacetime coding scheme for amplify-and-forward cooperative networks

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Science in china(Series F) 2009年第8期52卷 1418-1427页

作者： YU XiangBin1,2. BI GuangGuo3 & XU WeiYe4 1 College of Information Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 2.0016, china 2.Department of Electronic Engineering, City University of Hong Kong, Hong Kong, china 3 National Mobile Communications Research Laboratory, Southeast University, Nanjing 2.0096, china 4 Department of Communication Engineering, Nanjing institute of Technology, Nanjing 2.1167, china College of Information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Electronic Engineering City University of Hong Kong Hong Kong China National Mobile Communications Research Laboratory Southeast University Nanjing China Department of Communication Engineering Nanjing Institute of Technology Nanjing China

By introducing a space-time coding scheme based on amicable orthogonality, we develop a distributed differential space-time coding scheme with the amplify-and-forward （AF） method for wireless cooperative networks. The scheme requires no knowledge of the channel state information at both transmitters and receivers, and effectively decreases the realization complexity due to no channel estimation. Moreover, it has lower decoding complexity and higher coding advantage than the existing scheme, thus avoiding the shortcoming of exponential decoding complexity of some existing schemes. According to the pairwise error probability （PEP） analysis of the system, the power allocations of source and relay terminals are jointly optimized, and as a result, the PEP is minimized, which will provide a helpful guideline for system design. Numerical calculation and simulation results show that the developed scheme is superior to the existing scheme. Moreover, the scheme with optimal power allocation yields obvious performance improvement over that with equal power allocation.

关键词： differential space-time coding cooperative communication amplify-and-forward method power allocation

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秘密共享新个体加入协议的安全性分析与改进

通信学报 2009年第10期30卷 118-123页

作者：许静芳崔国华程琦张志华中科技大学计算机学院信息安全实验室湖北武汉430074 武汉市数字工程研究所湖北武汉430074

针对一个秘密共享新个体加入协议,具体地给出了2.攻击,使得不良的广播接收者可以很容易的恢复出t个旧成员的秘密份额si,进而恢复出新个体的秘密份额sn+1和主秘密S,并且证明了导致这2.攻击成功的根本原因。此外,提出了一个新的改进方案... 详细信息

针对一个秘密共享新个体加入协议,具体地给出了2.攻击,使得不良的广播接收者可以很容易的恢复出t个旧成员的秘密份额si,进而恢复出新个体的秘密份额sn+1和主秘密S,并且证明了导致这2.攻击成功的根本原因。此外,提出了一个新的改进方案,改进方案不仅弥补了原方案的安全缺陷,而且与已有的协议相比需要更少的通信量。

关键词：秘密共享新个体加入秘密份额恢复

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三门峡潼关高程可能降低的幅度研究

水力发电学报 2003年第3期22卷 68-78页

作者：周建军林秉南清华大学水利系北京100084 中国水科院国际泥沙研究中心北京100044

本文根据三门峡水库长期运行和水库冲淤的资料对潼关高程可以降低的幅度进行了分析。若现在起完全敞泄三门峡水库 ,在较枯的水沙条件下 (如 1 986～ 1 993年系列 ) ,可以将潼关高程降低到 32.6m附近 ;在近年极枯的水沙条件下 ( 1 994～ ... 详细信息

本文根据三门峡水库长期运行和水库冲淤的资料对潼关高程可以降低的幅度进行了分析。若现在起完全敞泄三门峡水库 ,在较枯的水沙条件下 (如 1 986～ 1 993年系列 ) ,可以将潼关高程降低到 32.6m附近 ;在近年极枯的水沙条件下 ( 1 994～ 1 999年 ) ,将潼关高程降低到32.7m以下也是可能的。所以 ,小浪底水库建成后 ,放弃三门峡水库发电等任务就可以降低潼关高程 ,一定程度上消除三门峡水库长期以来对于渭河造成的不利影响 ,为渭河流域的持续发展创造条件。

关键词：泥沙三门峡水库潼关高程泥沙淤积可能性生态恢复

利用CO2.ECBM技术在沁水盆地开采煤层气和埋藏CO2.潜力

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天然气工业 2009年第4期29卷 117-120页

作者：王烽汤达祯刘洪林刘玲李贵中王勃中国地质大学(北京)能源学院中国石油勘探开发研究院廊坊分院

利用CO2.ECBM技术在深部煤层进行CO2.藏不仅对减缓全球气候变暖具有重大意义,而且能够促进煤层气增产,是CO2.排最有效方式之一。沁水盆地为一NNE复向斜构造,其边缘地区由于断裂发育、强水动力条件和煤矿的开采,不利于CO2.藏。盆地中... 详细信息

利用CO2.ECBM技术在深部煤层进行CO2.藏不仅对减缓全球气候变暖具有重大意义,而且能够促进煤层气增产,是CO2.排最有效方式之一。沁水盆地为一NNE复向斜构造,其边缘地区由于断裂发育、强水动力条件和煤矿的开采,不利于CO2.藏。盆地中心区稳定的构造环境、弱水动力条件及良好的区域性盖层为CO2.藏提供了很好的保存条件。依据前人关于CO2.CH4等温吸附特性相关实验参数,初步评价了CO2.ECBM技术在沁水盆地开采煤层气和埋藏CO2.潜力。结果表明:CO2.ECBM技术可使沁水盆地煤层气可采量增加1.04×1012.3,埋藏CO2.可达47.7×108t。

关键词：沁水盆地 CO2.ECBM 温室气体煤层气采收率 CO2.CH4置换比

On the intergranular fracture behavior of high-temperature plastic deformation of 142. Al-Li alloy

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Rare Metals 2002年第1期21卷 67-73页

作者： TANGAitao WANGLingyun LIUXuefeng HUANGGuangjie CollegeofMaterialScienceandEngineering ChongqingUniversityChongqing400044China DepartmentofMetallicMaterials SichuanUniversityChengdu610065China

The tensile deformation hot simulation test of as-cast 142. Al-Li alloy was performed on Gleeble-1500 Thermal Simulator in the deformation temperature range from 350 to 450 ℃ and the strain rate range from 0.01 to *** tensile fracture behavior of the 142. Al-Li alloy at high temperature was studied experimently. The results show that the tensile fracture mode of the 142. Al-Li alloy at high temperature is changed from typical transgranular ductile fracture to intergranular brittle fracture with the increase of the deformation temperature and the strain rate. It is made out that the precipitation of LiH is the fundamental reason for the intergranular brittle fracture of the 142. Al-Li alloy at high temperature. The mechanism of hydrogen embrittlement of the 142. Al-Li alloy at high temperature was discussed, and it was proposed that the hydrogen embrittlement at high temperature is an integrated function of the dynamic and the static force, which enrichs the theories of hydrogen embrittlemen t.

关键词： Al-Li alloy high-temperature plastic deformation hydrogen embrittlement intergranular fracture

Environmental significance exploration to Tamarix ConeAge Layer in Lop Nur Lake region

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Science Bulletin 2005年第20期 141-143页

作者： XIA Xuncheng1, ZHAO Yuanjie2.1, WANG Fubao3 & CAO Qiongying3 1. Xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, china 2. College of {2. and Environmental Sciences, Hebei Normal University, Shijiazhuang 050016, china 3. Department of Urban and {2. Sciences, Nanjing University, Nanjing 2.0093, china

The production and cytotoxicity of the reactive oxygen species (ROS) induced by diallyl trisulfide (DATS) in human myeloid leukemia HL-60 cells

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The production and cytotoxicity of the reactive oxygen speci...

EFFECTS OF WAVE-CURRENT INTERACTIONS ON BOTTOM STRESS AND CURRENTS

两岸三地药理学与临床药理学术会议

作者： ZHANG Meng-xia~2.TIAN Zhi-zhen~1 TU Jian~1 ZHANG Xiao-hong~2.LEI Xiao-yong~1 TANG Sheng-song~(1,2. (1. institute of Pharmacy and Pharmacology,University of South china, Hengyang 42.001, china 2. Center for Life Sciences, University of South china, Hengyang 42.001, china)

Objective To explore the production and cytotoxicity of the reactive oxygen species(ROS)in- duced by diallyl trisulfid(DATS)in HL-60 *** HL-60 cells were either treated with various dos- es of DATS alone,or DATS combination with Apocynin,a specific NADPH oxidase inhibitor,or with an- tioxidant N-acetyl-L-cysteine(NAC)for 0,1,3,6,12.and 2. hours,*** intracellular ROS lev- el was measured by flow *** activity of NADPH oxidase was evaluated by NBT reduction exper- *** content of both malondialdehyde(MDA)and the protein carbonyl was analyzed by spectropho- *** The results from flow cytometry indicated that DATS significantly increased the intracellu- lar ROS level in HL-60 cells(P<0.05),which is a dose-and *** fluorescence intensities of ROS reached at maximuam when HL-60 cells were incubated with 150μmol·LDATS for 3 *** NBT reduction experiment showed that DATS activated NADPH oxidase which had highest activity when cell were exposed to 150μmol·LDATS for 3 *** DATS induced MDA and protein carbonyl production in HL-60 ***,both MDA and protein carbonyl in the cells exposed to 150μmol·LDATS for 3 hours reached the highest *** and NAC could attenuate the production of MDA and protein carbonyl,which suggested that ROS induced by DATS was involved in the toxicity to cells. Conclusions DATS induce ROS production through activating NADPH oxidase in HL-60 *** induced by DATS increase the oxidation of the membrane lipid and the protein of HL-60 cell.

关键词： diallyl trisulfide reactive oxygen species malondialdehyde protein carbonyl

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Journal of Hydrodynamics 2003年第5期15卷 13-19页

作者： YinBao-shu YangDe-zhou LinXiang HouYi-jun ChengMing-hua WillPerrie instituteofOceanology ChineseAcademyofSciencesQingdao266071China TrafficandOceanEngineeringCollege HohaiUniversityNanjing210098China BedfordinstituteofOceanography DartmouthNovaScotiaB2Y4A2Canada GraduateSchooloftheChineseAcademyofSciences Beijing100039China

This paper presents a high-resolution (2.X2.) numerical model of coastalcoupled wave-current interaction with explicit consideration of the effects of wave-currentinteraction on bottom stress. For two selected storms with measured data in the Yellow River coastalarea of the Bohai Sea, it is shown that the bottom stress calculated by using a coupledwave-current model is increased, as one would expect, compared with the bottom stress computed withan uncoupled current model. Moreover, the current velocity field is also changed, but thecorresponding current directions show less influence in the two simulations. The extents of changesin bottom stress and current velocity vary with storm intensities. The results further imply thatthe coupled wave-current model should be used as the basis for simulating the current velocity andsea level in the near shore region.

关键词： coupled wave-current model bottom stress coastal area