The continuously increasing production of municipal solid waste incineration bottom ash (MSWIBA) has promoted its utilization as construction material and raised environmental concern. The physico-chemical propertie...The continuously increasing production of municipal solid waste incineration bottom ash (MSWIBA) has promoted its utilization as construction material and raised environmental concern. The physico-chemical properties and leaching behavior of MSWIBA were studied, and ecotoxicological testing using a luminescent bacterium bioassay was performed to assess the ecological pollution risks associated with its leached constituents. The MSWIBA was leached by two types of leachants, H2SO4/HNO3 and HAc solution, at different liquid to solid ratios and contact times. The concentrations of heavy metals and anions in the leachates were analyzed. Multi- variate statistical analyses, including principle component analysis, Pearson's correlation analysis and hierarchical cluster analysis, were used to evaluate the contributions of the constituents to the toxicity (ECso) of the MSWIBA leachate. The statistical analyses of the ecotoxicological results showed that the Ba, Cr, Cu, Pb, F and total organic carbon (TOC) concentrations were closely correlated with the ECso value, and these substances were the main contributors to the ecotoxicity of the MSWIBA leachate. In addition, the cluster of these variables indicated similar leaching behaviors. Overall, the research demonstrated that the ecotoxicological risks resulting from MSWIBA leaching could be assessed before its utilization, which provides crucial information for the adaptation of MSWIBA as alternative materials.展开更多
Mixed crude palm oil (MCPO), the mixture of palm fiber oil and palm kernel oil, has become of great interest as a renewable energy source. It can be easily extracted from whole dried palm fruits. In the present work...Mixed crude palm oil (MCPO), the mixture of palm fiber oil and palm kernel oil, has become of great interest as a renewable energy source. It can be easily extracted from whole dried palm fruits. In the present work, the degummed, deacidified MCPO was blended in petroleum diesel at portions of 30% and 40% by volume and then tested in agricultural diesel engines for long term usage. The particulates from the exhaust of the engines were collected every 500 hr using a four-stage cascade air sampler. The 50% cut-off aerodynamic diameters for the first three stages were 10, 2.5 and 1μm, while the last stage collected all particles smaller than 1 μm. Sixteen particle bounded polycyclic aromatic hydrocarbons (PAHs) were analyzed using a high performance liquid chromatography. The results indicated that the size distribution of particulate matter was in the accmnulation mode and the pattern of total PAHs associated with fine-particles (〈 1 μm) showed a dominance of larger molecular weight PAHs (4--6 aromatic rings), especially pyrene. The mass median diameter, PM and total PAH concentrations decreased when increasing the palm oil content, but increased when the running hours of the engine were increased. In addition, Commercial petroleum diesel (PB0) gave the highest value of carcinogenic potency equivalent (BaPeq) for all particle size ranges. As the palm oil was increased, the; BaPeq decreased gradually. Therefore the degununed-deacidified MCPO blends are recommended for diesel substitute.展开更多
In recent times,multiple Unmanned Aerial Vehicles(UAVs)are being widely utilized in several areas of applications such as agriculture,surveillance,disaster management,search and rescue operations.Degree of robustness ...In recent times,multiple Unmanned Aerial Vehicles(UAVs)are being widely utilized in several areas of applications such as agriculture,surveillance,disaster management,search and rescue operations.Degree of robustness of applied control schemes determines how accurate a swarm of UAVs accomplish group tasks.Formation and trajectory tracking controllers are required for the swarm of multiple UAVs.Factors like external environmental effects,parametric uncertainties and wind gusts make the controller design process as a challenging task.This article proposes fractional order formation and trajectory tacking controllers for multiple quad-rotors using Super Twisting Sliding Mode Control(STSMC)technique.To compensate the effects of the disturbances due to parametric uncertainties and wind gusts,Lyapunov function based adaptive controllers are formulated.Moreover,Lyapunov theorem is used to guarantee the stability of the proposed controllers.Three types of controllers,namely fixed gain STSMC and fractional order Adaptive Super Twisting Sliding Mode Control(ASTSMC)methods are tested for the swarm of UAVs by performing the numerical simulations in MATLAB/Simulink environment.From the presented results,it is verified that in presence of wind disturbances and parametric uncertainties,the proposed fractional order ASTSMC technique showed improved robustness as compared to the fixed gain STSMC and integer order ASTSMC.展开更多
The use of coal fly ash(CFA), municipal solid waste incinerator bottom ash(MSWIBA) and flue gas desulfurization residue(FGDR) in road construction has become very common owing to its economical advantages. Howev...The use of coal fly ash(CFA), municipal solid waste incinerator bottom ash(MSWIBA) and flue gas desulfurization residue(FGDR) in road construction has become very common owing to its economical advantages. However, these residues may contain toxic constituents that pose an environmental risk if they leach out and flow through the soil, surface water and groundwater.Therefore, it is necessary to assess the ecotoxicity and groundwater impact of these residues before decisions can be made regarding their utilization for road construction. In this study,the physico-chemical characteristics, leaching and phytotoxicity of these residues were investigated. Specifically, multivariate analyses were used to evaluate the contributions of the leaching constituents of the CFA, MSWIBA and FGDR leachates to the germination index of wheat seeds. B, Ba, Cr, Cu, Fe and Pb were found to be more toxic to the wheat seeds than the other heavy metals. Furthermore, the leached concentrations of the constituents from the CFA, MSWIBA and FGDR were below the regulatory threshold limits of the Chinese identification standard for hazardous wastes. Analyses conducted using a numerical groundwater model(Wisc LEACH) indicated that the predicted field concentrations of metals from the CFA, MSWIBA and FGDR increased with time up to about 30 years at the point of compliance, then decreased with time and distance. Overall, this study demonstrated that the risks resulting from MSWIBA, CFA and FGDR leaching could be assessed before its utilization for road construction, providing crucial information for the adoption of these alternative materials.展开更多
基金The authors gratefully acknowledge the financial supports from the National Basic Research Program of China (No. 2011CB201500), the National Social Science Fund of China (No. 12&ZD236), the National Natural Science Foundation of China (Grant No. 21277096), and the Collaborative Innovation Center for Regional Environ- mental Quality.
文摘The continuously increasing production of municipal solid waste incineration bottom ash (MSWIBA) has promoted its utilization as construction material and raised environmental concern. The physico-chemical properties and leaching behavior of MSWIBA were studied, and ecotoxicological testing using a luminescent bacterium bioassay was performed to assess the ecological pollution risks associated with its leached constituents. The MSWIBA was leached by two types of leachants, H2SO4/HNO3 and HAc solution, at different liquid to solid ratios and contact times. The concentrations of heavy metals and anions in the leachates were analyzed. Multi- variate statistical analyses, including principle component analysis, Pearson's correlation analysis and hierarchical cluster analysis, were used to evaluate the contributions of the constituents to the toxicity (ECso) of the MSWIBA leachate. The statistical analyses of the ecotoxicological results showed that the Ba, Cr, Cu, Pb, F and total organic carbon (TOC) concentrations were closely correlated with the ECso value, and these substances were the main contributors to the ecotoxicity of the MSWIBA leachate. In addition, the cluster of these variables indicated similar leaching behaviors. Overall, the research demonstrated that the ecotoxicological risks resulting from MSWIBA leaching could be assessed before its utilization, which provides crucial information for the adaptation of MSWIBA as alternative materials.
基金supports from Prince of Songkla University(an annual research grant for fiscal years 2008-2010),the Center of Excellence for Innovation in Chemistry(PERCH-CIC),Office of the Higher Education Commission,Ministry of Education,Thailandthe Chaipattana Foundation under the support of the King of Thailand
文摘Mixed crude palm oil (MCPO), the mixture of palm fiber oil and palm kernel oil, has become of great interest as a renewable energy source. It can be easily extracted from whole dried palm fruits. In the present work, the degummed, deacidified MCPO was blended in petroleum diesel at portions of 30% and 40% by volume and then tested in agricultural diesel engines for long term usage. The particulates from the exhaust of the engines were collected every 500 hr using a four-stage cascade air sampler. The 50% cut-off aerodynamic diameters for the first three stages were 10, 2.5 and 1μm, while the last stage collected all particles smaller than 1 μm. Sixteen particle bounded polycyclic aromatic hydrocarbons (PAHs) were analyzed using a high performance liquid chromatography. The results indicated that the size distribution of particulate matter was in the accmnulation mode and the pattern of total PAHs associated with fine-particles (〈 1 μm) showed a dominance of larger molecular weight PAHs (4--6 aromatic rings), especially pyrene. The mass median diameter, PM and total PAH concentrations decreased when increasing the palm oil content, but increased when the running hours of the engine were increased. In addition, Commercial petroleum diesel (PB0) gave the highest value of carcinogenic potency equivalent (BaPeq) for all particle size ranges. As the palm oil was increased, the; BaPeq decreased gradually. Therefore the degununed-deacidified MCPO blends are recommended for diesel substitute.
基金supported by Prince of Songkla Universitythe Ministry of Higher Education,Science,Research and Innovation,under the Reinventing University Project(No.REV64022)。
文摘In recent times,multiple Unmanned Aerial Vehicles(UAVs)are being widely utilized in several areas of applications such as agriculture,surveillance,disaster management,search and rescue operations.Degree of robustness of applied control schemes determines how accurate a swarm of UAVs accomplish group tasks.Formation and trajectory tracking controllers are required for the swarm of multiple UAVs.Factors like external environmental effects,parametric uncertainties and wind gusts make the controller design process as a challenging task.This article proposes fractional order formation and trajectory tacking controllers for multiple quad-rotors using Super Twisting Sliding Mode Control(STSMC)technique.To compensate the effects of the disturbances due to parametric uncertainties and wind gusts,Lyapunov function based adaptive controllers are formulated.Moreover,Lyapunov theorem is used to guarantee the stability of the proposed controllers.Three types of controllers,namely fixed gain STSMC and fractional order Adaptive Super Twisting Sliding Mode Control(ASTSMC)methods are tested for the swarm of UAVs by performing the numerical simulations in MATLAB/Simulink environment.From the presented results,it is verified that in presence of wind disturbances and parametric uncertainties,the proposed fractional order ASTSMC technique showed improved robustness as compared to the fixed gain STSMC and integer order ASTSMC.
基金supported by the National Basic Research Program (973) of China (No. 2011CB201500)the National Natural Science Foundation of China (No. 21277096)+1 种基金the Collaborative Innovation Center for Regional Environmental Qualitythe China Scholarship Council (CSC), Ministry of Education, China (No. 2011GXZT67)
文摘The use of coal fly ash(CFA), municipal solid waste incinerator bottom ash(MSWIBA) and flue gas desulfurization residue(FGDR) in road construction has become very common owing to its economical advantages. However, these residues may contain toxic constituents that pose an environmental risk if they leach out and flow through the soil, surface water and groundwater.Therefore, it is necessary to assess the ecotoxicity and groundwater impact of these residues before decisions can be made regarding their utilization for road construction. In this study,the physico-chemical characteristics, leaching and phytotoxicity of these residues were investigated. Specifically, multivariate analyses were used to evaluate the contributions of the leaching constituents of the CFA, MSWIBA and FGDR leachates to the germination index of wheat seeds. B, Ba, Cr, Cu, Fe and Pb were found to be more toxic to the wheat seeds than the other heavy metals. Furthermore, the leached concentrations of the constituents from the CFA, MSWIBA and FGDR were below the regulatory threshold limits of the Chinese identification standard for hazardous wastes. Analyses conducted using a numerical groundwater model(Wisc LEACH) indicated that the predicted field concentrations of metals from the CFA, MSWIBA and FGDR increased with time up to about 30 years at the point of compliance, then decreased with time and distance. Overall, this study demonstrated that the risks resulting from MSWIBA, CFA and FGDR leaching could be assessed before its utilization for road construction, providing crucial information for the adoption of these alternative materials.