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Expansive Behaviors of Self-stressing Concrete under Different Restraining Conditions

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Journal of wuhan university of Technology(Materials Science) 2011年第4期26卷 780-785页

作者：常旭 College of Civil engineering Henan Polytechnic University

The expansive behaviors of the expensive concrete under different restraining conditions were systemically studied. The experimental results indicate that expansive deformation obviously increases before 10 days and tends to be constant after 2. days regardless of the restraining conditions. The mixture ratio of expansive cement and restraining conditions are the main factors affecting expansive deformation. Self-stress can be obtained when the expansive deformation is restrained. The higher self-stress could be obtained when the expensive concrete is restrained by steel tube. For specimens under steel tube restraining, the wall thickness and the length of the steel tube have important influence on self-stress. Both the radial self-stress and axial self-stress in concrete core increase when wall thickness or length of the steel tube increases.

关键词： self-stress expansive concrete restraining condition

Temperature-controlled ionic liquid dispersive liquid phase microextraction combined with ultra-high-pressure liquid chromatography for the rapid determination of triclosan,triclocarban and methyl-triclosan in aqueous samples

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Science china Chemistry 2010年第12期53卷 2600-2607页

作者： GUO JieHong 1,2.LI XingHong 2.CAO XueLi 1,QU Lei 2.3.HOU DeKun 2.& XU XiaoBai 2.1 School of Chemical and Environmental engineering,Beijing Technology and Business university,Beijing 100048,{2. 2.state key laboratory of Environmental Chemistry and Eco-toxicology Research Center of Eco-Environmental sciences,Chinese Academy of sciences,Beijing 100085,{2. 3.Zhengzhou university,Zhengzhou 450001,{2. 1. School of Chemical and Environmental engineering Beijing Technology and Business University Beijing 100048 China2. State Key Laboratory of Environmental Chemistry and Eco-toxicology Research Center of Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China3. Zhengzhou University Zhengzhou 450001 China

As extraction solvents,ionic liquids have green *** this study,an environmentally benign analytical method termed temperature-controlled ionic liquid dispersive liquid phase microextraction (TIL-DLME) combined with ultra-highpressure liquid chromatography (UHPLC)-tunable ultraviolet detection (TUV) was developed for the pre-concentration and determination of triclosan (TCS),triclocarban (TCC) and methyl-triclosan (M-TCS) in water *** parameters that may affect extraction efficiencies were examined and optimized,including the types and amount of ionic liquids,volume of the diluent,heating temperature,cooling time,salt effect and pH *** the optimum conditions,linearity of the method was observed in the ranges of 0.0100-100 μgL-1 for TCS and M-TCS,and 0.00500-50.0 μgL-1 for TCC with correlation coefficients (r2. > *** limits of detection (LODs) ranged from 1.15 to 5.3. *** in domestic water and TCC in reclaimed water were detected at the concentrations of 1.01 and 0.12. μgL-1,*** spiked recoveries of the three target compounds in reclaimed water,irrigating water,waste water and domestic water samples were obtained in the ranges of 68.4%-71.9%,61.6%-87.8%,58.9%-74.9% and 64.9%-92.4%,*** with the previous dispersive liquid-liquid microextraction method (DLLME) about the determination of TCS,TCC and M-TCS,this method is not only more environmentally friendly but also more sensitive.

关键词： ionic liquid temperature-controlled ionic liquid dispersive liquid phase microextraction UHPLC aqueous samples

NUMERICAL STUDY OF FLOW AND DILUTION BEHAVIOR OF RADIAL WALL JET

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Journal of Hydrodynamics 2010年第5期22卷 681-688页

作者： LI Zhi-wei HUAI Wen-xin QIAN Zhong-dong ZENG Yu-hong YANG Zhong-hua state key {2. of {3. Resources and hydropower engineering Science Wuhan University Wuhan 430072 China

The radial wall jet is a flow configuration that combines the radial jet and the wall jet. This article presents a simulation of the radial wall jet by applying the transition Shear-Stress Transport （ SST） model. Tanaka’s experimental data are used for validation. The computed velocity profiles agree well with the experimental ones. The distributions of the velocity on cross-sections show a similarity in the main region and the profiles are different with those of the free radial jet or the wall jet, because the presence of the wall limits the expansion of the jet. By introducing the equivalent nozzle width, the maximum velocity decays and the half-width distributions are normalized, respectively. In addition to compare the flow field with experiments, this paper also analyzes the dilution effect of radial wall jets in terms of the concentration distributions. The concentrations on the wall keep constant within a certain distance from the nozzle. And the concentration distributions also show a similarity in the main region. Both the decays of the maximum concentration and the distributions of the concentration half-width fall into a single curve, respectively. The dilution effect of radial wall jets is thus verified.

关键词： radial wall jet velocity profile concentration distribution concentration half-width

Total control-based unified allocation model for allowable basin water withdrawal and sewage discharge

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Science china(Technological sciences) 2010年第5期53卷 1387-1397页

作者： HU SiYi1,2.WANG ZongZhi1,WANG YinTang1 & ZHANG LingLing3.1 state key {2. of Hydrology-water Resources and Hydraulic engineering,Nanjing Hydraulic Research Institute,Nanjing 2.002.,china 2.Ministry of water Resources,the People’s Republic of china,Beijing 100053.china 3.School of Public Administration,HoHai {13.,Nanjing 2.0098,china 1. state key {2. of Hydrology-{3. Resources and Hydraulic engineering Nanjing Hydraulic Research Institute Nanjing 210029 China2. Ministry of Water Resources the People’s Republic of China Beijing 100053 China3. School of Public Administration HoHai University Nanjing 210098 China

In this paper,a new model with a total amount control target of allowable water withdrawal based on initial water right is built for the implementation of initial water right allocation scheme as well as unified allocation for allowable water withdrawal and sewage *** model couples the water allocation simulation model and the computational model of permissible pol-lution bearing *** view of the model complexity,a new technology which synthesizes system simulation,iterative reservoir turns and intelligent computation is proposed to improve the operability of allocation scheme and computational *** the Beijiang River Basin in the Pearl River Basin as an example,the study explains the model establishment,solution and application,and draws an optimized operation graph of large-scale *** study also obtains a long-term operation strategy of river basin water resources system,the allocation schemes of allowable water withdrawal and sewage discharge in a typical year and the flow hydrographs of trans-boundary *** validity of the model and the allocation rationality are analyzed as well.

关键词： water resources management total control unified control of water withdrawal and sewage discharge optimized regulation integration technology

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大坝安全监测系统综合评价指标体系研究

水力发电学报 2011年第4期30卷 175-180页

作者：何金平施玉群吴雯娴武汉大学水资源与水电工程科学国家重点实验室武汉430072 武汉大学水利水电学院武汉430072

依据现行技术规范和已有的工程实践经验,构建一个具有四层三级结构的大坝安全监测系统综合评价指标体系,提出单项评价指标和整体系统工作状态的四级评价等级划分方法,分析定量评价指标和定性评价指标隶属度的确定方法,给出各评价指标的... 详细信息

依据现行技术规范和已有的工程实践经验,构建一个具有四层三级结构的大坝安全监测系统综合评价指标体系,提出单项评价指标和整体系统工作状态的四级评价等级划分方法,分析定量评价指标和定性评价指标隶属度的确定方法,给出各评价指标的权重建议值,从而对大坝安全监测系统的定量综合评价问题进行较为系统的研究,为大坝安全监测系统综合评价实践提供可资借鉴的方法,并可为将来制定大坝安全监测系统综合评价的相关规范提供依据。

关键词：水工结构评价指标综合评价大坝监测系统

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府环河流域综合节水潜力分析

水电能源科学 2011年第2期29卷 103-104,185页

作者：汪奎武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

基于国内外节水潜力内涵和计算方法,提出了流域综合节水潜力的概念。以府环河流域为例,根据2.08年用水指标构建了流域综合节水潜力计算指标体系,并分析计算了流域广阔的节水前景。结果表明,采取有效节水措施后流域综合节水量6.94×108m3...

基于国内外节水潜力内涵和计算方法,提出了流域综合节水潜力的概念。以府环河流域为例,根据2.08年用水指标构建了流域综合节水潜力计算指标体系,并分析计算了流域广阔的节水前景。结果表明,采取有效节水措施后流域综合节水量6.94×108m3.占2.08年总用水量的2..9%。

关键词：节水潜力流域综合节水潜力节水指标指标体系府环河流域

Thermal stabilization of chromium slag by sewage sludge: Effects of sludge quantity and temperature

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Journal of Environmental sciences 2010年第7期22卷 1110-1115页

作者： Changlin Wu,Hua Zhang,Pinjing He,Liming Shao state key {2. of Pollution Control and Resources Reuse,key {2. of Yangtze River water Environment,College of Environmental Science & engineering,Tongji university,Shanghai 2.0092.china. [a] state key {2. of Pollution Control Resources Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science & Engineering Tongji University Shanghai 200092 China. E-mail: solidwaste@***

To investigate the feasibility of detoxifying chromium slag by sewage sludge, synthetic chromium slag containing 3. of Cr（Ⅵ） was mixed with sewage sludge followed by thermal treatment in nitrogen gas for stabilizing chromium. The effects of slag to sludge ratio （0.5, 1 and 2. and temperature （2.0, 3.0, 500, 700 and 900℃） on treatment efficiency were investigated. During the mixing process before thermal treatment, 59.8%-99.7% of Cr（Ⅵ） was reduced, but Cr could be easily leached from the reduction product. Increasing heating temperature and decreasing slag to sludge ratio strengthened the reduction and stabilization of Cr（Ⅵ）. When the slag to sludge ratio was 0.5 and thermal treatment temperature was 3.0℃, the total leached Cr and Cr（Ⅵ） declined to 0.55 mg/L and 0.17 mg/L respectively, and 45.5% of Cr in the thermally treated residue existed as residual fraction. A two-stage mechanism was proposed for the reduction and stabilization of Cr.

关键词： chromium slag sewage sludge reduction detoxification thermal treatment leached concentration

Enzyme extraction by ultrasound from sludge flocs

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Journal of Environmental sciences 2009年第2期21卷 204-210页

作者： YU Guanghui,HE Pinjing,SHAO Liming,ZHU Yishu state key {2. of Pollution Control and Resource Reuse,key {2. of Yangtze River water Environment,College of Environmental Science and engineering,Tongji university,Shanghai 2.0092.china. state key {2. of Pollution Control and Resource Reuse Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China

Enzymes play essential roles in the biological processes of sludge treatment. In this article, the ultrasound method to extract enzymes from sludge flocs was presented. Results showed that using ultrasound method at 2. kHz could extract more types of enzymes than that at 40 kHz and ethylenediamine tetraacetic acid （EDTA） methods. The optimum parameters of ultrasound extraction at 2. kHz were duration of 10 min and intensity of 552.W/g TSS. Under the optimum condition, ultrasound could break the cells and extract both the extracellular and a small part of intercellular enzymes. Ultrasound intensity was apparently more susceptive to enzyme extraction than duration, suggesting that the control of intensity during ultrasound extraction was more important than that of duration. The Pearson correlation analysis between enzyme activities and cation contents revealed that the different types of enzymes had distinct cation binding characteristics.

关键词： enzymes extracellular polymeric substances extraction method sludge flocs statistical analysis ultrasound

Anti-Crack Performance of Phosphorus Slag Concrete

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wuhan university Journal of Natural {2. 2009年第1期14卷 80-86页

作者： CHEN Xia ZENG Li FANG Kunhe states key {2. of {3. Resource and hydropower engineering Science Wuhan University Wuhan 430072 Hubei China

Anti-crack performance of concrete with phosphorus slag and fly ash singly and compositely added is investigated in terms of physical performance, hydration heat, dry shrinkage and creep. Index K is introduced to evaluate the crack resistance of phosphorus slag concrete. Results show that the strength of phosphorus slag concrete increases with the increase of fineness, and when surface specific area is greater than 3.0 m^2.kg, the tendency slows down. Strength decreases with phosphorus slag content increasing and there is an optimal content existing between 3.% and 50%. Both phosphorus slag and fly ash have obvious effect on elongating time setting, reducing hydration heat to a large extent and increasing creep value. Crack resistance of phosphorus slag concrete is divided into three stages, namely early hazardous stage, growth stage and later mature stage. With microstructure analysis, mechanism of effect of phosphorus slag on concrete performances and P and F on cement hydration is explored. It is concluded after comprehensive evaluation that the crack resistance of phosphorus slag concrete is approximate to, even to some extent better than that of fly ash concrete.

关键词： phosphorus slag creep anti-crack performance mechanism