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集水面积阈值确定方法的比较研究

水电能源科学 2009年第5期27卷 11-14,171页

作者：杨邦任立良河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对坡面径流模拟算法引入集水面积阈值划分流域内的河网与坡地直接影响了生成的数字河网精度,探讨并比较了多种推求流域集水面积阈值的方法。结果表明,各种方法可互补;采用集水面积与河道平均坡降关系和采用集水面积与河网密度曲线具... 详细信息

针对坡面径流模拟算法引入集水面积阈值划分流域内的河网与坡地直接影响了生成的数字河网精度,探讨并比较了多种推求流域集水面积阈值的方法。结果表明,各种方法可互补;采用集水面积与河道平均坡降关系和采用集水面积与河网密度曲线具有较好的一致性;流域面积越大,采用宽度分布推求阈值准确,流域面积越小,采用水系分形推求阈值准确;集水面积阈值在流域内各处并非完全相同,应考虑采用多个阈值。

关键词：集水面积阈值数字高程模型数字水系分形河网宽度

Heavy-duty anticorrosive Zn-Al composite coatings for offshore steel structure

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Heavy-duty anticorrosive Zn-Al composite coatings for offsho...

2011中国材料研讨会

作者： Fumin Lu a,Aibin Ma a,b,Jinghua Jiang a,b,Liuyan Zhang a,Dan Song a,Donghui Yang a,Jianqing Chen a a College of Mechanics and Materials,hohai university,nanjing 210098,china b national engineering research center of water resources efficient utilization and engineering safety,hohai university,nanjing 210098,china

With aim to protect the steel tower part of wind power facility against marine corrosion,three kinds of heavy-duty anticorrosive composite coatings （CZ,CA and CZA） were *** a three-layer system,the composite coating consists of arc-sprayed metallic （Zn,Al or Zn-15mass%Al） coating （primer layer）,epoxy paint pigmented with micaceous iron oxide （intermediate layer） and acrylic polyurethane coating （surface layer）.The corrosion behaviors of single-layer arc-sprayed metallic coatings （SZ,SA and SZA） were investigated by potentiodynamic polarization tests,electrochemical impedance spectroscopy （EIS） analyses and SEM *** suit performance of composite coatings was evaluated by salt spray *** results indicated that the SZA coating behaved both good blocking effect like SA coating and good ability of cathodic protection like SZ ***,the CZA coating with excellent suit performance and good stability satisfied the request for long-term anti-corrosion for offshore steel structure.

关键词： electric arc spraying corrosion behavior composite coating suit performance durability

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大坝安全监控PCA-BP融合模型研究

水电能源科学 2011年第2期29卷 47-49,34页

作者：刘红萍马文丽河海大学水利水电学院江苏南京210098 河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

针对大坝资料分析中经常遇到多因子的相关性影响分析效果的问题,利用主成分分析法提取综合变量,与BP神经网络相融合构建了大坝安全监控PCA-BP融合模型,并与传统大坝安全监控模型做了对比分析。结果表明,模型优化拟合精度得到提高,收敛... 详细信息

针对大坝资料分析中经常遇到多因子的相关性影响分析效果的问题,利用主成分分析法提取综合变量,与BP神经网络相融合构建了大坝安全监控PCA-BP融合模型,并与传统大坝安全监控模型做了对比分析。结果表明,模型优化拟合精度得到提高,收敛时间加快。

关键词：大坝安全监控模型主成分分析 BP神经网络

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基于折迭型突变模型的混凝土坝稳定分析

水电能源科学 2009年第2期27卷 107-108,96页

作者：张磊李波佟剑杰河海大学水利水电工程学院江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

基于折迭型突变及其势函数,结合某混凝土坝坝踵处钢板针实测资料,考虑水压、温度和时效因素建立了混凝土坝体稳定的统计模型并进行稳定分析,结果表明该处坝体稳定,与坝体实际情况相符。

关键词：混凝土坝突变理论折迭型突变稳定分析

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基于小波分析的大坝监测数据效应分量的提取

水电能源科学 2009年第5期27卷 81-82,80页

作者：崔永建张磊佟剑杰河海大学水利水电工程学院江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

将大坝监测的数据序列视为一串由不同频率组成的数字信号,利用多分辨分析提出了基于小波分析提取大坝监测数据效应分量的方法,给出了该法的的基本原理和计算思路。以棉花滩碾压混凝土坝水平位移监测数据为例,分离结果表明,小波变换在分... 详细信息

将大坝监测的数据序列视为一串由不同频率组成的数字信号,利用多分辨分析提出了基于小波分析提取大坝监测数据效应分量的方法,给出了该法的的基本原理和计算思路。以棉花滩碾压混凝土坝水平位移监测数据为例,分离结果表明,小波变换在分离效应分量具有较好的实用性和操作性。

关键词：小波分析效应分量大坝观测数据提取

大坝位移监控模型温度分量的欠拟合原因及改进

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水电能源科学 2009年第6期27卷 72-75,52页

作者：刘贝贝陈坤城佟剑杰河海大学水利水电工程学院江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098

分析了目前通用的大坝位移数学监控模型对原型监测数据产生欠拟合问题的原因,指出影响模型拟合精度的关键是过于简化了温度分量表达式。根据热量在坝体内外发生传递特点建立微小时段内的坝体热力学模型,分析了温度效应对坝体位移影响规... 详细信息

分析了目前通用的大坝位移数学监控模型对原型监测数据产生欠拟合问题的原因,指出影响模型拟合精度的关键是过于简化了温度分量表达式。根据热量在坝体内外发生传递特点建立微小时段内的坝体热力学模型,分析了温度效应对坝体位移影响规律并引入瑞利分布函数描述其影响过程,结合经扩充的温度分量因子集以数值积分形式给出改进后的大坝位移数学模型温度分量的表达式。实例结果表明拟合效果良好。

关键词：数学模型欠拟合滞后传导瑞利分布

Dicamba and Sugar Effects on Callus Induction and Plant Regeneration from Mature Embryo Culture of Wheat

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Agricultural Sciences in china 2010年第1期9卷 31-37页

作者： REN Jiang-ping,WANG Xin-guo and YIN Jun national engineering research center for Wheat/Henan Agricultural university,Zhengzhou 450002,P.R.china national engineering research center for Wheat/Henan Agricultural university Zhengzhou 450002 P.R. China

To establish a highly efficient plant regeneration system for wheat genetic transformation, the effects of three different concentrations of dicamba and two different sugar types on callus induction and plant regeneration from mature embryo cultures were evaluated. Callus induction and plant regeneration were obtained from mature embryos of two commercial cultivars Zhoumai 18 and Yumai 34 （Triticum aestivum L.） cultured on L3 basal medium. The results showed that the efficiency of mature embryo culture was significantly influenced by the genotypes, sugar types and dicamba concentrations. 4 mg L^-1 dicamba proved the best effective for inducing embryogenic callus and also gave the highest proportion of plants regenerated across the two cultivars. Substitution of maltose by sucrose significantly improved the plant regeneration efficiency in both cultivars. There was a significant interaction between genotype-by-sugar types, and sugar types-bydicamba concentrations. Overall, Zhoumai 18 gave the highest frequency of plant regeneration （82.65%） when dicamba concentration was 4.0 mg L^-1 and with sucrose in initial callus induction. These results will facilitate genetic transformation work with elite wheat.

关键词： wheat mature embryo tissue culture plant regeneration

Designing a green and efficient absorbent for CO_2 capture

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化工进展 2011年第S2期30卷 167-170页

作者： DAI Yue,WANG Guannan,WU Youting,ZHANG Zhibing (Separation engineering research center,School of Chemistry and Chemical engineering, nanjing university,nanjing 210093,Jiangsu,china)

Several task-specific ionic liquids（TSILs） with weak alkalinity have been designed based on tetraalkyl-ammonium cation and L-alanine anion([N2222][L-Ala]) for the CO2 absorption.[N2222][L-Ala]has been chosen as a green and efficient activator for methyldiethanolamine（MDEA）.The densities,viscosities and absorption properties of the equimolar[N2222][L-Ala]-MDEA blended absorbents were *** viscosity and density values support the idea that blended absorbents are preferred in the industrial applications.[N2222][L-Ala]-MDEA behave similarly to the aqueous counterparts but offer more advantages,such as large absorption capacities,fast absorption rate and relatively low damage to the environment.

关键词： task-specific ionic liquid weak alkanility CO2 capture blended absorbents

Ni supported on activated carbon as catalyst for flue gas desulfurization

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Science china Chemistry 2010年第4期53卷 846-850页

作者： CHU YingHao1,2, GUO JiaXiu1,2, LIANG Juan1,2, ZHANG QiangBo1 & YIN HuaQiang1,2 1Department of Environmental Science and engineering, Sichuan university, Chengdu 610065, china 2national engineering Technology research center for Flue Gas Desulfurization, Sichuan university, Chengdu 610065, china Department of Environmental Science and engineering Sichuan University Chengdu China national engineering Technology research center for Flue Gas Desulfurization Sichuan University Chengdu China

A series of Ni supported on activated carbon are prepared by excessive impregnation and the desulfurization activity is investigated. It has been shown that the activated carbon-supported Ni is an efficient solid catalyst for flue gas desulfurization. The activated carbon treated by HNO3 exhibits high desulfurization activity, and different amounts of loaded-Ni on activated carbon significantly influence the desulfurization activity. The catalysts are studied by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results of XRD and XPS indicate that the activated carbon treated by HNO3 can increase oxygen-containing functional groups. Ni on activated carbon after calcination at 800 °C shows major Ni phase and minor NiO phase, and with increasing Ni content on activated carbon, Ni phase increases and affects the desulfurization activity of the catalyst, which proves that Ni is the main active phase.

关键词： activated carbon Ni desulfurization XRD XPS