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Properties of Leakage Corrosion of Concrete and Its Durability

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Journal of Wuhan university of Technology(Materials Science) 2008年第6期23卷 946-949页

作者：戈雪良 department of Materials and Structural Engineering Nanjing Hydraulic Research Institute

The properties and mechanism of concrete under water leakage corrosion were studied in terms of the dissolution of calcium oxide and silicon oxide from concrete and the variation of pH value of permeate *** experimental results show that the amount of calcium oxide and silicon oxide dissolved from per cubic meter of concrete gradually decrease with penetration time and ultimately stabilize at a certain *** pH value of permeate water descend along with penetration *** durability of concrete under leakage corrosion was analyzed by a formula fitted on the dissolved amount of calcium oxide.

关键词： concrete leakage corrosion properties durability

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花尾胡椒鲷染色体组型分析

海洋学报 2003年第4期25卷 147-150页

作者：覃映雪苏永全王胜强王德祥王军厦门大学海洋学系亚热带海洋研究所福建厦门361005 国家海洋局人事司北京100860

1 引言一位著名的遗传学家说过,地球的历史记载于地壳中,而生物的历史却记载在染色体上,染色体作为遗传信息的载体具有种的特异性,不同的物种有其特定的染色体组型,在很大程度上染色体的组型反映了物种的进化历史和种间的亲缘关系。因... 详细信息

1 引言一位著名的遗传学家说过,地球的历史记载于地壳中,而生物的历史却记载在染色体上,染色体作为遗传信息的载体具有种的特异性,不同的物种有其特定的染色体组型,在很大程度上染色体的组型反映了物种的进化历史和种间的亲缘关系。因此,染色体组型研究成为细胞遗传学上一个不可缺少的部分,对种质资源的研究来说,更具有极其重要的意义。本文以我国沿海常见的经济鱼类花尾胡椒鲷为研究对象,分析了它的组型。

关键词：花尾胡椒鲷核型染色体组型细胞遗传学鲈形目遗传育种鱼类

Orthogonal design for optimization of pigment extraction from surface sediments of the Changjiang River Estuary

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Acta Oceanologica Sinica 2011年第4期30卷 33-42页

作者： ZHAO Jun YAO Peng YU Zhigang Thomas S Bianchi Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao 266100 China department of Oceanography Texas A ＆ M University College Station TX 77843 USA Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100 China Institute of Marine Organic Geochemistry College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

Using a suitable solvent for extracting pigments from sediment for high performance liquid chromatography（HPLC） analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass,as well as community composition. Five methodological factors（sample dehydration,extraction solvent,extraction duration,number of extractions,and ratio of solvent volume：sample weight） were studied using an L 9（3 4 ） orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary（LDE）,using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L 9（3 4 ） orthogonal design experiments and showed that the extraction solvent was the most important,with extraction duration the second most important,and numbers of extraction and ratio of solvent volume：sample weight was the least important. The mixed solvent treatment comprised of acetone,methanol and water（80：15：5,by volume） was best for polar pigment extraction,with 100% acetone better for apolar pigments. For most pigments employed in this study（i.e.,peridinin,fucoxanthin,alloxanthin,diatoxanthin,zeaxanthin,pheophytin-a and β-carotene） ,3 h was found to be enough time for extraction from these deltaic sediments. However,for chlorophyll-a,the most important pigment used for estimating algal biomass,12.h was needed. A small amount of solvent（3 ml） with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately,no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study,taking into consideration the properties of sediments and pigments in question.

关键词： sedimentary pigments extraction orthogonal design HPLC Changjiang River Estuary

A Kind of integral Representation on Riemannian Manifods

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Wuhan university Journal of Natural Sciences 1996年第1期1卷 14-16页

作者： Hu Jicheng (department of mathematics, Wuhan {2., Wuhan 430072.china)

We generalized the Bochner-Martinelli integral representation to that on Riemannian manifolds. Things become quite different in such case. First we define a kind of Newtonian potential and take the interior product of its gradient to be the integral kernel. Then we prove that this kernel is harmonic in some sense. At last an integral representative theorem is proved.

关键词： Riemannian manifold integral representation Newtonian potential

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三种鲍精子超微结构的比较

海洋学报 2003年第3期25卷 138-142页

作者：柯才焕周时强田越李复雪厦门大学海洋系海洋环境科学教育部重点实验室福建厦门361005

1 引言动物精子超微结构的研究是受精生物学的重要基础,而且由于系统分类的不同其精子的超微结构也伴随着演化,因此,研究和比较分类相似种的精子超微结构,可以作为鉴别种类的辅助依据,同时在动物杂交育种的细胞遗传学分析中也有一定的... 详细信息

1 引言动物精子超微结构的研究是受精生物学的重要基础,而且由于系统分类的不同其精子的超微结构也伴随着演化,因此,研究和比较分类相似种的精子超微结构,可以作为鉴别种类的辅助依据,同时在动物杂交育种的细胞遗传学分析中也有一定的参考价值。

关键词：鲍精子超微结构分类学进化

Application of PowerBuilder User Objects in Developing Distributed Programs

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Wuhan university Journal of Natural Sciences 2001年第4期6卷 822-825页

作者： Wang Li\|fu 1, Li Hua\|ming 2.1. Human Source department, Wuhan Telecom Industry Group Co. Ltd., Wuhan 430074, china 2.School of Physics and Technology, Wuhan {2.,Wuhan 430072.china Wuhan Telecom Industry Group Co. Ltd. Human Source Department Wuhan China Wuhan university School of Physics and Technology Wuhan China (GRID:grid.49470.3e) (ISNI:***)

User Objects are the basement in developing distributed PowerBuilder applications. There are two kinds of PowerBuilder objects: visual objects and non-visual objects. Usually we use non-visual objects to perform the PowerBuilder distriuted application. This paper introduces the method of developing PowerBuilder distributed application program, mainly discusses the application of nonvisual objects when developing PowerBuilder distributed application programs.

关键词： Key words PowerBuilder user object shared object remote object server push

ON THE POST-BUCKLING ANALYSIS OF PLASTIC STRUCTURES UNDER IMPULSIVE LOADING

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Acta Mechanica Sinica 1990年第1期6卷 45-49页

作者： Ru Chongqing Wang Ren, department of Mechanics, Peking university, Beijing,{2. 1. department of Mechanics Peking University Beijing China

An analytical method is suggested to analyze the plastic post-buckling behavior under impulsive loading. The fundamental equation of motion of a cylindrical shell is taken as an example to explain the main concept and procedure. The axial and the radial displacements are decoupled by an approximate scheme, so that only one non-linear equation for the radial buckling displacement is to be solved. By expanding it in terms of an amplitude measure as a time variable, we may get the post-buckling behavior in the form of a series solution. The post-buckling behavior of a rectangular plate used as a special case of cylindrical shell is discussed.

关键词： plastic buckling dynamic post-buckling cylindrical shell

Random walk modeling of wake dispersion for the exhaust tower of an underground tunnel in urban area

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Journal of Environmental Sciences 1999年第4期11卷 474-479页

作者： JIANG Wei\|mei\+1, YU Hong\|bin\+1, LI Xin\+2.(1.department of Atmospheric Sciences, Nanjing university, Nanjing 2.0093,{2. 2.LAPC, Institute of Atmospheric Physics,Chinese Academy of Sciences, Beijing 10002.,{2.) department of Atmospheric Sciences Nanjing University Nanjing 210093 China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

In this paper, some experimental studies on the impact of effluent from an exhaust tower of an underground tunnel with special construction are reported. By measuring the flow field downstream of the tower in NJU meteorological wind tunnel, some flow characteristics in the make area were established. Based on these, an advanced random\|walk dispersion model was set up and applied successfully to the simulation of dispersion in the wake area. The modelling results were in accordance with wind tunnel measurements. The computed maximum of ground surface concentration in the building case was a factor of 3-4 higher than that in the flat case and appeared much closer to the source. The simulation indicated that random walk modelling is an effective and practical tool for the wake stream impact assessment.

关键词： exhaust tower air pollution in urban area atmospheric dispersion random walk modelling

Minimum Exact Cover Problem of Group Key Distribution

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Wuhan university Journal of Natural Sciences 2009年第2期14卷 137-142页

作者： FU Xiong1,2. XU Shouzhi3 1. School of Law ,Wuhan university, Wuhan 430072. Hubei, china 2. {2. of Technology, Guangzhou Luogang District People’s Court, Guangzhou 510730, Guangdong, china 3. College of Electronic Engineering and Information Technology, china Three Gorges university, Yichang 443002. Hubei, china School of Law Wuhan University Wuhan 430072 Hubei China department of Technology Guangzhou Luogang District People’s Court Guangzhou 510730 Guangdong China College of Electronic Engineering and Information Technology China Three Gorges University Yichang 443002 Hubei China

Secure group communications are restrained by the number of the group size, number of changes and their distribution, all existing works do not meet the commands of applications with large group size and high dynamic members. In this paper, minimum exact cover problem for group key distribution （GMECP） is presented, and a heuristic solution is testified. Then an algorithm of batch rekeying with renewing cost tending to zero is illustrated, which can process any large number of change requests with best security guaranteed. Efficiency analysis and simulation test show that the achievement can improve the efficiency of any tree-based group key management.

关键词： minimum exact cover problem group key distribution secure multicast group key management