Adsorption of Cd(II) and Cu(II) onto Clay Modified with Sludge Activated Carbon
作者:
Li, Kaifan;Lu, Haijun* ;Zhang, Qian;Li, Jixiang
期刊:
KSCE Journal of Civil Engineering ,2020年24(6):1706-1716 ISSN:1226-7988
通讯作者:
Lu, Haijun
作者机构:
[Lu, Haijun; Zhang, Qian; Li, Jixiang; Li, Kaifan] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
通讯机构:
[Lu, Haijun] W;Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
关键词:
Sludge activated carbon;Modified clay;Adsorption;Heavy metals;Pore
摘要:
Sludge Activated carbon was prepared by heating dewatered municipal sludge to 400°C using ZnCl2 as an activator. The abilities of clay modified with 1%, 3%, and 5% of the sludge activated carbon to adsorb heavy metals were determined. The materials were subjected to scanning electron microscopy and low-temperature nitrogen-adsorption, extraction efficiency, adsorption kinetics, and isothermal adsorption tests to allow the pore sizes, pore volume distributions, pore structures, and adsorption capacities to be assessed. The pores were mostly mesopores and were mostly amorphous (e.g., ink-bottle-shaped holes). With the solid/liquid ratio kept constant, the adsorption capacity at equilibrium increased as the sludge activated carbon content of the clay increased. For clay modified with 1% sludge activated carbon, the adsorption capacity for Cd(II) at equilibrium decreased from 314 to 280 mg/kg as the solid/liquid ratio increased from 80 to 160 g/L. The adsorption capacities for Cu(II) at equilibrium at solid/liquid ratios of 80, 120, and 160 g/L were 442, 409, and 383 mg/kg, respectively, which were 41%, 34%, and 37% higher, respectively, than the Cd(II) adsorption capacities at the same solid/liquid ratios. It was concluded that the sludge activated carbon was suitable for trapping heavy metals such as Cd(II) and Cu(II). © 2020, Korean Society of Civil Engineers.
语种:
英文
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Experimental study on the permeability and microstructure of remoulded silty clay corroded by landfill leachate
作者:
Chaofeng Wang;Haijun Lu;Dinggang Li;Jixiang Li
期刊:
Nature Environment and Pollution Technology ,2020年19(3):1241-1248 ISSN:0972-6268
通讯作者:
Lu, H.
作者机构:
School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan, 430023, China;State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, 430071, China
通讯机构:
State Key Laboratory of Geomechanics and Geotechnical Engineering, Institute of Rock and Soil Mechanics, Chinese Academy of Sciences, Wuhan, China
关键词:
Feldspar;Hydraulic conductivity;Kaolinite;Mechanical permeability;Mica;Microstructure;Mineral exploration;Nuclear magnetic resonance;Organic pollutants;Pollution induced corrosion;Scanning electron microscopy;X ray diffraction;Corrosive environment;Development effect;Infiltration process;Landfill leachates;Macroscopic permeability;Microstructure changes;Mineral composition;X-ray diffraction tests;Leachate treatment;concentration (composition);detection method;experimental study;hydraulic conductivity;kaolinite;landfill;leachate;microstructure;permeability;silty clay;triaxial test
摘要:
This paper explores the macroscopic permeability characteristics, pore distribution, mineral composition, and microstructure changes in remoulded silty clay under different concentrations and different back pressures through flexible-wall triaxial permeability tests, nuclear magnetic resonance tests, X-ray diffraction tests, and scanning electron microscope tests. The results of the flexible-wall triaxial permeability tests indicate that the hydraulic conductivity of the landfill leachate with different concentrations increases to the peak value in 108-132 h period and then decreases to a stable value in 252-264 h period under the action of different back pressures. The nuclear magnetic resonance tests show that the pore distribution of the remoulded silty clay is macropore after it is corroded by the leachate. Increasing the concentration of landfill leachate and reducing the back pressures can reduce the overall development effect of pores. The X-ray diffraction tests show that the weakly acidic corrosive environment provided by remoulded silty clay and landfill leachate reduce respectively the contents of montmorillonite, muscovite, and illite by 33.52 %, 23.57 % and 63.51 %, while kaolinite and albite increase by 283.40 % and 188.64 %. Finally, scanning electron microscope tests show that the corrosion of landfill leachate and the plugging of organic pollutants in the infiltration process reduce the apparent pore ratio of the microstructure of remoulded silty clay and the hydraulic conductivity gradually decreases. © 2020 Technoscience Publications. All rights reserved.
语种:
英文
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Bayesian Approach for Sequential Probabilistic Back Analysis of Uncertain Geomechanical Parameters and Reliability Updating of Tunneling-Induced Ground Settlements
作者:
Li, Cong;Jiang, Shui-Hua* ;Li, Jinhui;Huang, Jinsong
期刊:
Advances in Civil Engineering ,2020年2020(1):8528304 ISSN:1687-8086
通讯作者:
Jiang, Shui-Hua
作者机构:
[Jiang, Shui-Hua; Li, Cong; Huang, Jinsong] Nanchang Univ, Sch Civil Engn & Architecture, 999 Xuefu Rd, Nanchang 330031, Jiangxi, Peoples R China.;[Li, Cong] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Hubei, Peoples R China.;[Jiang, Shui-Hua] Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.;[Li, Jinhui] Harbin Inst Technol Shenzhen, Dept Civil & Environm Engn, Shenzhen 518055, Peoples R China.
通讯机构:
[Jiang, Shui-Hua] N;[Jiang, Shui-Hua] C;Nanchang Univ, Sch Civil Engn & Architecture, 999 Xuefu Rd, Nanchang 330031, Jiangxi, Peoples R China.;Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.
摘要:
This paper proposes a new sequential probabilistic back analysis approach for probabilistically determining the uncertain geomechanical parameters of shield tunnels by using time-series monitoring data. The approach is proposed based on the recently developed Bayesian updating with subset simulation. Within the framework of the proposed approach, a complex Bayesian back analysis problem is transformed into an equivalent structural reliability problem based on subset simulation. Hermite polynomial chaos expansion-based surrogate models are constructed to improve the computational efficiency of probabilistic back analysis. The reliability of tunneling-induced ground settlements is updated in the process of sequential back analyses. A real shield tunnel project of No. 1 Nanchang Metro Line in China is investigated to assess the effectiveness of the approach. The proposed approach is able to infer the posterior distributions of uncertain geomechanical parameters (i.e., Young's moduli of surrounding soil layers and ground vehicle load). The reliability of tunneling-induced ground settlements can be updated in a real-time manner by fully utilizing the time-series monitoring data. The results show good agreement with the variation trend of field monitoring data of ground settlement and the post-event investigations. © 2020 Cong Li et al.
语种:
英文
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An experimental study on the microstructure and triaxial shear of structured clay in contact with landfill leachate
作者:
Xu, Shicheng;Lu, Haijun* ;Liu, Junzhu;Li, Jixiang
期刊:
Bulletin of Engineering Geology and the Environment ,2019年78(6):4611-4622 ISSN:1435-9529
通讯作者:
Lu, Haijun
作者机构:
[Lu, Haijun; Xu, Shicheng; Li, Jixiang] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Hubei, Peoples R China.;[Lu, Haijun] Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.;[Liu, Junzhu] Beijing Geo & Inv Engn Inst, Beijing 100083, Peoples R China.
通讯机构:
[Lu, Haijun] W;[Lu, Haijun] C;Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Hubei, Peoples R China.;Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.
关键词:
Structured clay;Landfill leachate;Triaxial shear test;Microstructure;Particle distribution
摘要:
City solid waste stock has exceeded 8 billion tons in China, and the output and coverage area of solid waste are increasing daily. Landfill leachate can be generated during biodegradation of disposed and stored solid waste. Leachate contains high concentrations of organic mixtures and heavy metal ions. Natural undisturbed soil has high anti-seepage capacity and its permeability coefficient is less than 1 x 10(-7) cm/s in underlying stratum, which can delay leachate contamination of the environment surrounding a landfill site. However, undisturbed soil exhibits certain structural characteristics. After long-term leachate corrosion, leachate leakage will inevitably influence the stability of stratum underlying a landfill. In this study, the mechanical characteristics of undisturbed clay under the actions of landfill leachate and stress were analyzed via a consolidated-undrained triaxial shear test. Comprehensive microstructure laboratory tests, including X-ray diffraction, scanning electron microscopy, and laser particle size tests, were performed to determine at different times the microstructure of undisturbed clay due to corrosion by landfill leachate. Experimental results indicate the strength and microstructural evolution of structured clay under the actions of landfill leachate and stress. The research results are helpful for evaluating the safety and predicting the stability of a landfill's underlying stratum.
语种:
英文
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Experimental Study on the Compression and Pore Characteristics of Undisturbed Loess Polluted by Landfill Leachate
作者:
Xu, Shicheng;Lu, Haijun;Li, Dinggang;Li, Jixiang;Wang, Weiwei
期刊:
Environmental Science and Engineering ,2019年:145-153 ISSN:1863-5520
通讯作者:
Lu, HJ
作者机构:
[Lu, Haijun; Li, Dinggang; Xu, Shicheng; Wang, Weiwei; Li, Jixiang] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
通讯机构:
[Lu, HJ ] W;Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
会议名称:
8th International Congress on Environmental Geotechnics (ICEG)
会议时间:
OCT 28-NOV 01, 2018
会议地点:
Hangzhou, PEOPLES R CHINA
会议主办单位:
[Xu, Shicheng;Lu, Haijun;Li, Dinggang;Li, Jixiang;Wang, Weiwei] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
会议论文集名称:
Environmental Science and Engineering
关键词:
Compressibility;Landfill leachate;Pore;Undisturbed loess
摘要:
This paper aims to investigate the compression and pore characteristics of underlying stratum in landfill. Batch tests were conducted to measure the compressibility as well as the pore, mineral, and microstructure characteristics of the undisturbed loess polluted by landfill leachate under different concentrations. Results show that the compressibility and compressive deformation of undisturbed soil increased as the landfill leachate concentrations increased. The reduction range of the void ratio was from 22.1% to 30.8%. The leachate pollution caused a decrease in the content of illite and montmorillonite, which reduced by 4.59% and 3.8%, respectively. The NMR signal of undisturbed soil increased as the landfill leachate concentrations increased. The pore radius of the undisturbed soil was mainly distributed in the range of 0.01–1 μm and can be divided into two ranges. The inter-particle pores and intra-aggregate pores mainly existed in undisturbed soil polluted by landfill leachate. Leachate caused an increase in inter-particle pore, whereas a decrease in intra-aggregate pore radius. © Springer Nature Singapore Pte Ltd. 2019.
语种:
英文
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An Experimental Study of Mineral and Microstructure for Undisturbed Loess Polluted by Landfill Leachate
作者:
Lu, Haijun;Xu, Shicheng* ;Li, Dinggang;Li, Jixiang
期刊:
KSCE Journal of Civil Engineering ,2018年22(12):4891-4900 ISSN:1226-7988
通讯作者:
Xu, Shicheng
作者机构:
[Lu, Haijun; Li, Dinggang; Xu, Shicheng; Li, Jixiang] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Hubei, Peoples R China.
通讯机构:
[Xu, Shicheng] W;Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Hubei, Peoples R China.
关键词:
Honeycomb structures;Leachate treatment;Microstructure;Minerals;Particle size;Particle size analysis;Sediments;Soils;Stress-strain curves;Average particle size;Landfill leachates;Leachate concentrations;Mineral composition;Pore characteristics;Pore-water pressures;strength;Undisturbed loess;Soil pollution
摘要:
To investigate the shear strength and microstructure of undisturbed loess polluted by landfill leachate, a series of laboratory tests were carried out to determine the shear strength, mineral composition, surface morphology, particle size distribution and pore characteristics of the loess. The stress-strain curve of undisturbed soil polluted by landfill leachate showed typical strain-softening behavior. The deviatoric stress, cohesion and angle of shearing resistance of undisturbed soil decreased at increased landfill leachate concentrations, decreased by 31.03%, 30.01%, respectively. But pore water pressure was positively related to leachate concentrations. The content of primary minerals remained stable, and the content of montmorillonite and illite decreased with increased leachate concentration, reduced by 26.02%, 23.93%, respectively. Soil structure changed into an unstable honeycomb structure when the leachate concentration increased. Moreover, the average particle size decreased by 62.1%, and the specific surface area increased and then stabilized at 500 ~ 650 m2/kg. The soil particles became nonuniform and porous and their sizes gradually decreased. The pore radius of soil mainly ranged from 0.02 μm to 1 μm. The maximum radius and optimal radius of the pore increased when the leachate concentrations increased. © 2018, Korean Society of Civil Engineers.
语种:
英文
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An Experimental Study on Cement-Solidified Cd-Contaminated Soils under Drying-Wetting Cycles
作者:
Liu, Huikai;Lu, Haijun* ;Zhang, Xiong;Li, Jixiang;Wang, Weiwei
期刊:
JOURNAL OF TESTING AND EVALUATION ,2018年46(2):493-506 ISSN:0090-3973
通讯作者:
Lu, Haijun
作者机构:
[Lu, Haijun; Liu, Huikai; Wang, Weiwei; Li, Jixiang; Zhang, Xiong] Wuhan Polytech Univ, Inst Poromech, 68 South Rd, Wuhan 430023, Hubei, Peoples R China.
通讯机构:
[Lu, Haijun] W;Wuhan Polytech Univ, Inst Poromech, 68 South Rd, Wuhan 430023, Hubei, Peoples R China.
关键词:
Cadmium;Contamination;Costs;Cracks;Drying;Gas adsorption;Gas permeability;Health hazards;Health risks;Hydraulic conductivity;Leaching;Soil cement;Soils;Temperature;Wetting;Cd-contaminated soils;Commercial availability;Drying-wetting cycle;Heavy metal contaminated soils;Leaching concentrations;Low-temperature nitrogen;pore;Solidification/stabilization;Soil pollution
摘要:
Many human activities can produce and release cadmium (Cd) to air, water, and soils. Soils are the major sink for Cd released into the environment. Unlike organic contaminants, which are oxidized to carbon (IV) oxide by microbial action, Cd does not undergo microbial or chemical degradation, and its total concentration in soils persists for a long time after introduction. The excessive presence of Cd in soil poses great risks and hazards to human health and is detrimental to the ecosystem. In the past 50 years, cement-based solidification/stabilization (S/S) of heavy metal-contaminated soil has received increasing research attention, and its application has expanded because of its advantages over many other existing methods such as relatively low cost, good long-term effectiveness and performance, ready commercial availability, general acceptance by the public, etc. However, considering the lasting effect and environmental impact of the S/S method, as well as the complicated surroundings of cement-solidified Cd-contaminated soils, further research is needed. In this study, a comprehensive series of tests such as low-temperature nitrogen gas adsorption/desorption, permeability, and Cd leaching were performed to investigate the performance of Cd-contaminated soils solidified with 2 %, 5 %, 8 %, and 10 % of cement during a various number of drying-wetting (D-W) cycles. The focus was put on the cracking occurrences and evolution with the number of D-W cycles, their influences on the pore/crack size and distribution, hydraulic conductivity, and final concentration of Cd leaching. Based upon the analyses of the test results, some conclusions are drawn and the optimum percentage of cement treatment was suggested for the soils under investigation. © 2018 by ASTM International.
语种:
英文
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An experimental study on solidifying municipal sewage sludge through skeleton building using cement and coal gangue(Open Access)
作者:
Yang, Jiankang;Lu, Haijun;Zhang, Xiong;Li, Jixiang;Wang, Weiwei
期刊:
Advances in Materials Science and Engineering ,2017年2017:1-13 ISSN:1687-8434
通讯作者:
Lu, HJ
作者机构:
[Yang, Jiankang; Lu, Haijun; Li, Jixiang; Wang, Weiwei] Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.;[Zhang, Xiong] Missouri Univ Sci & Technol, Dept Civil Architectural & Environm Engn, Rolla, MO USA.
通讯机构:
[Lu, HJ ] ;Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.
摘要:
The municipal sewage sludge typically has very high water content and low shear strength. Conventional methods of lime and cement solidification of municipal sewage sludge often suffer high cost, significant drying shrinkage, frequent cracking, high hydraulic conductivity, and low strength. To overcome these shortcomings, in this paper a skeleton-building method was used to solidify municipal sewage sludge in which coal gangue, cement and clay, and fiber were used as skeleton materials, cementation materials, and filling materials, respectively. Comprehensive laboratory tests including cracking, nitrogen adsorption, triaxial shearing, and permeability tests were performed to determine cracking, pore structure, shear strength, and hydraulic conductivity of municipal sewage sludge solidified with different proportions of coal gangue, cement, fiber, and clay. Based upon the experimental results, the mechanisms of the skeleton building using cement and coal gangue were discussed and factors controlling the mechanical and hydraulic behavior of the solidified soils were analyzed at both microscopic and macroscopic levels. Based upon the test results and analyses, recommendations were made for solidifying municipal sewage sludge through skeleton building using cement and coal gangue. The solidified soils have high soil strength, high resistance to cracking, and low hydraulic conductivity which are sufficient for being used as landfill liner.<br/> ©2017 Jiankang Yang et al.
语种:
英文
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Properties of Polymer-Modified Mortar Using Silane as an Integral Additive
作者:
Liu, Jiesheng* ;Liu, Ke;Zhang, Juan;Li, Jixiang
期刊:
JOURNAL OF TESTING AND EVALUATION ,2016年44(1):175-182 ISSN:0090-3973
通讯作者:
Liu, Jiesheng
作者机构:
[Zhang, Juan; Liu, Jiesheng; Li, Jixiang; Liu, Ke] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
通讯机构:
[Liu, Jiesheng] W;Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.
关键词:
Carbonation;Chlorine compounds;Compressive strength;Cracks;Microstructure;Scanning electron microscopy;Carbonation resistance;Chloride;Degree of hydration;Micro voids;Polarizing microscopy;Polymer modified mortar;Water penetration;Mortar
摘要:
In the present paper, the addition of silane to improve the properties of mortar was experimentally investigated. The morphology and microstructure of mortar were investigated by using both scanning electron microscopy (SEM) and polarizing microscopy (PM). The results show that silane significantly alters the microstructure of mortar, reduces the crystallization, restricts the degree of hydration of cement-based materials, and decreases micro-voids. As a result, silane effectively improves the chemical and carbonation resistance, as well as the chloride and water penetration resistance of mortar. Results also indicate that the consistency of mortar was improved but the compressive strength of the mortar was decreased. Specifically, silane would also be beneficial to the bridging cracking function to resist crack propagation.
语种:
英文
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The Adsorption Capacity, Pore Structure, and Thermal Behavior of the Modified Clay Containing SSA
作者:
Lu, Haijun* ;Zhang, Qian;Dong, Yiqie;Li, Jixiang;Zhang, Xiong
期刊:
Advances in Materials Science and Engineering ,2016年2016:1-7 ISSN:1687-8434
通讯作者:
Lu, Haijun
作者机构:
[Lu, Haijun; Dong, Yiqie; Zhang, Qian; Li, Jixiang; Zhang, Xiong] Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.
通讯机构:
[Lu, Haijun] W;Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.
摘要:
Sewage sludge ash (SSA) was created by burning municipal sludge. The potential of clay containing 1 or 3 or 5% SSA was assessed for use as a landfill liner-soil material. Batch adsorption, low temperature N2 adsorption, and TG-DTA tests were performed to evaluate the adsorption capacity, micropore structure, thermostability, and components of soils under Cr(VI) and Pb(II) chemical solutions. With the increasing amount of SSA in modified clay, the adsorption capacity of Cr(VI) and Pb(II) to the modified clay increases gradually. After absorption, the pore size of modified clay ranges from 2 nm to 8 nm. With the increasing amount of absorption, the pore volume decreases and the specific surface area increases. With the increasing of adsorption concentration of Cr(VI) and Pb(II), the mass loss percentage of modified clay increases to 23.4% and 12.6%, respectively. The modified clay containing SSA may be used as a good barrier material to attenuate contamination of Cr(VI) and Pb(II) in landfills. © 2016 Haijun Lu et al.
语种:
英文
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The strength deformation and microstructure properties of clay contaminated by landfill leachate
作者:
Zhang, Qian;Lu, Haijun* ;Dong, Yiqie;Li, Jixiang
期刊:
Nature Environment and Pollution Technology ,2016年15(4):1231-1236 ISSN:0972-6268
通讯作者:
Lu, Haijun
作者机构:
[Li, Jixiang; Lu, Haijun; Dong, Yiqie; Zhang, Qian] Institute of Poromechanics, Wuhan Polytechnic University, Wuhan, 430023, China
通讯机构:
Institute of Poromechanics, Wuhan Polytechnic University, Wuhan, China
关键词:
Clay;Compressive strength;Corrosion;Deformation;Gas adsorption;Microporosity;Microstructure;Nitrogen;Pore size;Compressive testing;Contaminated clays;Corrosion degree;Landfill leachates;Landfill liner system;Microstructure properties;Nitrogen adsorption;Unconfined compressive strength;Leachate treatment;adsorption;clay;compressive strength;corrosion;deformation;landfill liner;leachate;microstructure;nitrogen;pollutant;pore space;shear strength;testing method
摘要:
In order to research the corrosive state of landfill liner system, which affected by landfill leachate, and explore its strength and microstructure properties, contacting reaction between landfill leachate and compacted clay landfill liner system was simulated. Then, clay samples of different layers were investigated by unconfined compressive testing, shear testing and static nitrogen adsorption testing. The results showed that corrosion degree of clay samples caused by landfill leachate increased with the decrease of deepness of clay. And the maximum unconfined compressive strength (UCS) decreased obviously along with the shear strength. The UCS at 10cm was 53.1% that of layer at 50cm and the shear strength was 40.4∼62.4% at 10cm that of 50cm. The static nitrogen adsorption testing showed that the shape of clay particle was bottleneck like, and with the decrease of the depth of clay, there was a decrease in the number of micropores whose size was no smaller than 6nm. And the number of pores which was between 2nm and 5nm increased. In addition, there also appeared micropore which was smaller than 2nm. And the average pore size was decreased from 5.083nm at 50cm to 3.768nm at 10cm.
语种:
英文
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The leachate release and microstructure of the sewage sludge under the anaerobic fermentation
作者:
Dong, Yiqie;Lu, Haijun* ;Li, Jixiang;Wang, Changhong
期刊:
Journal of Chemistry ,2015年2015:1-9 ISSN:2090-9063
通讯作者:
Lu, Haijun
作者机构:
[Wang, Changhong; Lu, Haijun; Dong, Yiqie; Li, Jixiang] Wuhan Polytech Univ, Inst Porous Mech, Wuhan 430023, Peoples R China.
通讯机构:
[Lu, Haijun] W;Wuhan Polytech Univ, Inst Porous Mech, Wuhan 430023, Peoples R China.
摘要:
Pollutant release, pore structure, and thermal effect of sewage sludge during anaerobic fermentation were investigated. Results showed that the pH value firstly declined and then increased during anaerobic fermentation. The BODand organics of sewage sludge declined, and the BODof samples which was originally neutral declined as much as 53.6%. The micropore of samples was relatively developed. The biggest adsorption amount was 69.2 cm3/g. The average pore size was enlarged about 16.0-19.8% under anaerobic fermentation. There existed endothermic valley during heating procedure of 0-200°C because of the dehydration, and the mass loss was 60.9-72.5%. The endothermic valley of the sample fluctuated at the 14th day in the anaerobic fermentation. During the heating procedure of 200-600°C, there existed exothermal peaks because of the oxidation and burning of the organics. The curve of sample which was originally neutral had comparatively large endothermic valley and exothermal peak. © 2015 Yiqie Dong et al.
语种:
英文
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The adsorption capacity and geotechnical properties of modified clay containing SSA used as landfill liner-soil materials
作者:
Lu, Haijun* ;Dong, Yiqie;Li, Jixiang;Wang, Changhong
期刊:
Journal of Chemistry ,2015年2015:1-7 ISSN:2090-9063
通讯作者:
Lu, Haijun
作者机构:
[Lu, Haijun] Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.;[Wang, Changhong; Lu, Haijun; Dong, Yiqie; Li, Jixiang] Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.
通讯机构:
[Lu, Haijun] C;Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.
摘要:
The potential of clay containing 05% sewage sludge ash (SSA) is assessed for use as a landfill liner-soil material. Low temperature Nadsorption, batch adsorption, permeability, and unconfined compressive strength tests are performed to evaluate pore structure, adsorption capacity, hydraulic conductivity, and unconfined compressive strength of the clays. The pore size distribution of the modified clay containing SSA is mainly composed of micropores (<2 nm) and mesopores (27 nm). With the increasing of SSA from 0% to 5%, the adsorption capacity of Zn(II) and Cu(II) to the clay increases 37% and 273%, respectively. The hydraulic conductivity of modified clay is from 3.62 × 10-8 to 2.17 × 10-8 cm/s. At SSA = 3%, the unconfined compressive strength of the clay reaches the maximum value of 601.1 kPa. After the clay containing SSA is contaminated by acid and alkali chemical solutions, the amount of mesopores and hydraulic conductivity increase. The adsorption capacity and unconfined compressive strength of contaminated clay decrease about 2∼44% and 25.7∼38.2%, respectively. The modified clay containing SSA can meet the adsorption and geotechnical requirement of landfill liners. © 2015 Haijun Lu et al.
语种:
英文
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CDIO与土木工程专业人才培养方案研究
作者:
黎丹;刘肖凡;李进;余文晖
期刊:
中国建设教育 ,2015年(01):50-52
作者机构:
武汉轻工大学土木工程与建筑学院
关键词:
卓越计划;土木工程专业;培养方案
摘要:
CDIO工程教育模式与我国的卓越工程师教育具有很大的一致性。作为地方普通院校,土木工程专业首先从人才培养方案上作了改革,在明确专业培养目标、制订专业培养标准、构建一体化课程计划、实施多元教学方法等方面进行了实践和创新,为着手实施"卓越工程师教育培养计划"打下了良好基础。
语种:
中文
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Cracking and water seepage of Xiashu loess used as landfill cover under wetting-drying cycles
作者:
Lu, Haijun;Li, Jixiang* ;Wang, Weiwei;Wang, Changhong
期刊:
Environmental Earth Sciences ,2015年74(11):7441-7450 ISSN:1866-6280
通讯作者:
Li, Jixiang
作者机构:
[Wang, Changhong; Lu, Haijun; Wang, Weiwei; Li, Jixiang] Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.
通讯机构:
[Li, Jixiang] W;Wuhan Polytech Univ, Inst Poromech, Wuhan 430023, Peoples R China.
关键词:
Landfill cover;Cracks;Pores;Hydraulic conductivity;Water seepage
摘要:
This paper intends to investigate the anti-seepage characteristics of Xiashu loess used as landfill cover under wetting–drying cycles. A series of tests were performed to systematically evaluate the surface cracks, pores, the hydraulic conductivity and water seepage of the soil under wetting–drying cycles. The cracking tests indicated that the cracking intensity factor (CIF) increased with the number of wetting–drying cycles. After three wetting–drying cycles, the CIF gradually reached a stable value. The influence of the compactness of the compacted clay was significant to cracking. After four drying–wetting cycles, the CIF of compacted clay with relatively low compactness (ρ=1.65g/cm3, W5=25%) was 0.15, and the CIF of compacted clay with higher compactness (ρ=1.65g/cm3, W3=21%) was only 0.06. With the increase in the number of wetting–drying cycles, the accumulated pore volume of the soil particles increased and the maximum pore size was nearly unchanged. After four drying–wetting cycles, the proportion and average diameter of macro-pore in the soil particles were both increased. However, the proportion and average diameter of the meso-pore slightly decreased. Furthermore, the proportion and average diameter of the micro-pores were unchanged. After four wetting–drying cycles, the hydraulic conductivity of the compacted soil was at 8.3×10−7–1.5×10−5cm/s, which was increased about three orders of magnitude compared with the compacted soil without cracks. The hydraulic conductivity of compacted soil increased linearly as cracks increased. The hydraulic conductivity of compacted soil also gradually increased to a stable value as the pore volume increased. After 1 month of wetting–drying cycles, the cracks of soil with low compactness had extended to a depth of 15cm below the soil surface while the cracks of soil with higher compactness only reached a depth of 5cm. © 2015, Springer-Verlag Berlin Heidelberg.
语种:
英文
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学案教学模式在大学课堂应用中的研究与探索
作者:
李进
期刊:
中国建设教育 ,2015年(01):58-60
作者机构:
武汉轻工大学土木工程与建筑学院
关键词:
学案;学生;大学课堂;自学
摘要:
目前各大学课程教学改革进行得如火如荼,其中最关注的是教学方法的更新与创新,在各学校实践与探索过程中,我们获得一个共识:学生的学习不应该只求一个结果,更重要的是知识的获取过程。是教促学,还是学促教?目前传统的传授式教学效果日益退化,新的教学模式已逐渐被接受并应用。经研究发现在教学过程中应该提高学生的自主学习意识,给其自主学习机会,引导其主动积极自主学习,使学生在学习期间不仅仅是学习,而是学会学习。这便是时下流行的"学案导学"的核心思路。
语种:
中文
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Synergistic effects and Cracking Bending Strength for Steel-polypropylene Hybrid Fiber Reinforced Concrete
作者:
Mei, Guodong* ;Liu, Xiaofan;Li, Jixiang;Duan, Wenfu
期刊:
Advanced Materials Research ,2013年652-654:1237-1241 ISSN:1022-6680
通讯作者:
Mei, Guodong
作者机构:
[Liu, Xiaofan; Li, Jixiang; Mei, Guodong] Wuhan Univ, Sch Civil Engn, Wuhan 430072, Peoples R China.;[Duan, Wenfu] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.;Wuhan Opt Valley Construct Invest Co Ltd, Wuhan 430205, Peoples R China.
通讯机构:
[Mei, Guodong] W;Wuhan Univ, Sch Civil Engn, Wuhan 430072, Peoples R China.
会议名称:
3rd International Conference on Advances in Materials Manufacturing (ICAMMP 2012)
会议时间:
DEC 22-23, 2012
会议地点:
Beihai, PEOPLES R CHINA
会议主办单位:
[Mei, Guodong;Liu, Xiaofan;Li, Jixiang] Wuhan Univ, Sch Civil Engn, Wuhan 430072, Peoples R China.^[Duan, Wenfu] Wuhan Polytech Univ, Sch Civil Engn & Architecture, Wuhan 430023, Peoples R China.^Wuhan Opt Valley Construct Invest Co Ltd, Wuhan 430205, Peoples R China.
会议论文集名称:
Advanced Materials Research
关键词:
Bending test;Cracking bending strength;Hybrid fiber;Steel fiber;Synergistic effect
摘要:
The cracking bending strength for steel-polypropylene hybrid fiber reinforced concrete (HFRC) had been studied based on experimental test. the inicial cracking strength achieve significant improvement compare to plain concrete, and the highest increase is 16.7%. There is a synergistic effect exist when steel fiber is 1.0% in volume or polypropylene fiber is 0.1% in volume, and the synergistic effect raise to vertex (1.043) when both of those two requirements are fulfilled.
语种:
英文
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A study of data mining technology in customer relations management
作者:
Jin Li
期刊:
Lecture Notes in Electrical Engineering ,2013年163 LNEE:735-740 ISSN:1876-1100
通讯作者:
Li, J.(1714064990@qq.com)
作者机构:
[Jin Li] School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan, China
会议名称:
2012年控制与信息国际会议
会议时间:
2012-09-21
会议地点:
中国重庆
关键词:
Business decision supports;Business management;Customer data;Customer relations;Customer relations management;Data mining technology;Technical support;Business decision supports;Business management;Customer data;Customer relations;Customer relations management;Data mining technology;Technical support;Cybernetics;Data mining;Decision support systems;Information science;Public relations;Cybernetics;Data mining;Decision support systems;Information science;Life cycle;Management;Public relations;Sales;Management;Decision making
摘要:
This article has analyzed the customer relations management, the data mining technology, as well as based on the customer life cycle; the data mining performs in the customer relations management's application to introduce and the analysis separately. The data mining may help the enterprise in the customer relations management's application in the magnanimous customer data to discover that the valuable knowledge and the pattern, become meet the enterprise need, provides the effective business decision support for the enterprise The customer relations management played the crucial role in the business management decision-making, but the data mining technology has provided the good technical support for the customer relations management's implementation. © 2013 Springer Science+Business Media.
语种:
英文
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Research of traffic evacuation methods of unexpected events
作者:
Wang, Fu;Li, Jie;Shi, Yong-Hui
期刊:
Lecture Notes in Electrical Engineering ,2011年87 LNEE(VOL. 2):479-486 ISSN:1876-1100
通讯作者:
Wang, F.(wangfu@whpu.edu.cn)
作者机构:
[Wang, Fu] School of Civil Engineering and Architecture, Wuhan Polytechnic University, Wuhan 430023, China;[Shi, Yong-Hui] Department of Scientific Research, Wuhan Traffic Management Bureau, Wuhan 430000, China;[Li, Jie; Wang, Fu] School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, Wuhan 430074, China
关键词:
Electrical engineering;Mathematical techniques;Estimation methods;Estimation results;One way traffic;One-way green waves;Traffic characteristics;Traffic Engineering;Traffic estimation;Unexpected events;Emergency traffic control
摘要:
To rescue and evacuate people of unexpected events in city, it is very necessary to organize traffic system. On the base of analyzing traffic characteristics of unexpected events, traffic evacuation methods are submitted, such as combination of one-way traffic and special use way, no turn -left, temporary traffic channeling, one-way green wave, and estimation methods also are set. Estimation result illustrates that these traffic evacuation methods of unexpected events can improve network capacity and promote rescue and evacuation. © 2011 Springer-Verlag Berlin Heidelberg.
语种:
英文
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Research on traffic organization and design parameter of U-turn intersection in city
作者:
Fu Wang;Jie Li;Yong-hui Shi
期刊:
2010 International Conference on Electrical and Control Engineering ,2010年:4172-4176
通讯作者:
Wang, F.
作者机构:
School of Civil Engineering & Mechanics, Huazhong University of Science and Technology, Wuhan, China;Department of Civil Engineering, Wuhan Polytechnic University, Wuhan, China;School of Environment and City, Wuhan Institute of Technology, Wuhan, China;[Yong-hui Shi] Department of Scientific Research, Wuhan Traffic Management Bureau, Wuhan, China;[Fu Wang] School of Civil Engineering & Mechanics, Huazhong University of Science and Technology, Wuhan, China<&wdkj&>Department of Civil Engineering, Wuhan Polytechnic University, Wuhan, China
通讯机构:
School of Civil Engineering and Mechanics, Huazhong University of Science and Technology, China
会议名称:
2010 International Conference on Electrical and Control Engineering
会议时间:
June 2010
会议地点:
Wuhan, China
会议论文集名称:
2010 International Conference on Electrical and Control Engineering
关键词:
intersection;traffic organization;U-turn;design parameter
摘要:
After analyzing the serious impact of left-turn vehicle on intersection, this paper offers the means of traffic organization by being use of U-turn for carrying out left-turn vehicles at intersection. Meanwhile, the paper gives the calculation models and reference values of design parameters about distance from intersection to U-turn hatch in center isolation, turn radius, and path width. The results indicate the technique of U-turn can cancel left-turn vehicles at intersection, reduce phase numbers of the traffic signals and decrease delay to enhance capacity and continuity of the arteries. © 2010 IEEE.
语种:
英文
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