While conventional wastewater treatments for urban effluents are fairly routine and have proved highly effective,industrial wastewater requires more complex and specific treatments.This paper provides a technological ...While conventional wastewater treatments for urban effluents are fairly routine and have proved highly effective,industrial wastewater requires more complex and specific treatments.This paper provides a technological strategy for removal of recalcitrant contaminants based on a hybrid treatment system.The model effluent containing a binary mixture of synthetic dyes is treated by a combination of a preliminary physicochemical stage followed by a biological stage based on ligninolytic enzymes produced by Phanerochaete chrysosporium.This proposal includes biosorption onto peat as pretreatment,which decreases the volume and concentration to be treated in the biological reactor,thereby obtaining a completely decolorized effluent.The treated wastewater can therefore be reused in the dyeing baths with the consequent saving of water resources.展开更多
Taguchi method with grey relational analysis was used to optimize the machining parameters with multiple performance characteristics in drilling hybrid metal matrix A1356/SiC-mica composites. Experiments were conducte...Taguchi method with grey relational analysis was used to optimize the machining parameters with multiple performance characteristics in drilling hybrid metal matrix A1356/SiC-mica composites. Experiments were conducted on a computer numerical control vertical machining centre and Lzs orthogonal array was chosen for the experiments. The drilling parameters namely spindle speed, feed rate, drill type and mass fraction of mica were optimized based on the multiple performance characteristics including thrust force, surface roughness, tool wear and burr height （exit）. The results show that the feed rate and the type of drill are the most significant factors which affect the drilling process and the performance in the drilling process can be effectively improved by using this approach.展开更多
Metal organic frameworks(MOFs)constructed from natural/biological units(amino acids)are prospective candidates as catalysts in CO2chemistry owing to their natural origin and high abundance of Lewis acid/base sites and...Metal organic frameworks(MOFs)constructed from natural/biological units(amino acids)are prospective candidates as catalysts in CO2chemistry owing to their natural origin and high abundance of Lewis acid/base sites and functional groups.Herein,we report the catalytic efficiency of an amino‐acid‐based Cu‐containing MOF,denoted as CuTrp(Trp=L‐tryptophan).The CuTrp catalyst was synthesized by direct mixing at room temperature using methanol as a solvent-a synthetic route with notable energy efficiency.The catalyst was characterized using various physicochemical techniques,including XRD,FT‐IR,TGA,XPS,ICP‐OES,FE‐SEM,and BET analysis.The catalytic activity of CuTrp was assessed in the synthesis of cyclic carbonates from epoxides and CO2.The CuTrp operated in synergy with the co‐catalyst tetrabutylammonium bromide under solvent‐free conditions.Several reaction parameters were studied to identify the optimal reaction conditions and a reaction mechanism was proposed based on experimental evidence and previous density functional theory studies.The CuTrp also exhibited satisfactory stability in water and could be reused more than three times without any significant loss of activity.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.展开更多
This study is aimed at the thermal analysis of sealant mortar （usually a mixtures of bentonite and cemem with addition of sand） used in geothermal cooling and heating. In particular, thermal conductivity and diffusi...This study is aimed at the thermal analysis of sealant mortar （usually a mixtures of bentonite and cemem with addition of sand） used in geothermal cooling and heating. In particular, thermal conductivity and diffusivity measurements were performed on differem sealant mixtures by using Hot Disk thermal constants analyzer in order to identify the interesting thermal properties of grouting materials. The grouting materials that we considered are of porous nature and, if used in the presence of groundwater, have different levels of imbibitions. It is important to know the thermal behavior of these materials at different water content. A first set of measurements was performed on a not-tinted material at room temperature; then the samples were led to saturation conditions by contact capillary imbibitions with a cotton wool layer moistened in water. The determination of thermal conductivity in these test conditions appears to be critical compared to the measuremems on non-timed sample. The thermal conductivity tests have revealed how the thermal behavior of the samples analyzed is essentially determined by the density and water content of the material： in fact, the thermal conductivity increases of two to three times the value of the not-tinted material.展开更多
π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenz...π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran)as the backbones have received considerable attention owing to their special structures and interesting electrochromic performances.Recent studies show that polymers from these structures exhibit decent contrast ratios,favorable coloration efficiencies,low switching voltages,fast response time,excellent stability,and color persistence.Intrinsically,their electrochromic properties significantly depend on fine-tailoring of precursor monomer structures,and polymerization techniques and conditions.This review devotes to showing a clear picture of the research progress of dibenzo pentacycle-centered CPs via electrochemical polymerization,including fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran-based hybrid electrochromic polymers.Critical influences of the tailored precursor structures on their electropolymerization and resultant polymer performances are highlighted,aiming at providing an insight for the development of novel fused ring-based polymer electrochromic materials.展开更多
基金Supported by the Proyecto Fondecyt (1040089,1090098)
文摘While conventional wastewater treatments for urban effluents are fairly routine and have proved highly effective,industrial wastewater requires more complex and specific treatments.This paper provides a technological strategy for removal of recalcitrant contaminants based on a hybrid treatment system.The model effluent containing a binary mixture of synthetic dyes is treated by a combination of a preliminary physicochemical stage followed by a biological stage based on ligninolytic enzymes produced by Phanerochaete chrysosporium.This proposal includes biosorption onto peat as pretreatment,which decreases the volume and concentration to be treated in the biological reactor,thereby obtaining a completely decolorized effluent.The treated wastewater can therefore be reused in the dyeing baths with the consequent saving of water resources.
基金SCSVMV University, Kanchipuram,India for funding and supporting this research work
文摘Taguchi method with grey relational analysis was used to optimize the machining parameters with multiple performance characteristics in drilling hybrid metal matrix A1356/SiC-mica composites. Experiments were conducted on a computer numerical control vertical machining centre and Lzs orthogonal array was chosen for the experiments. The drilling parameters namely spindle speed, feed rate, drill type and mass fraction of mica were optimized based on the multiple performance characteristics including thrust force, surface roughness, tool wear and burr height （exit）. The results show that the feed rate and the type of drill are the most significant factors which affect the drilling process and the performance in the drilling process can be effectively improved by using this approach.
文摘Metal organic frameworks(MOFs)constructed from natural/biological units(amino acids)are prospective candidates as catalysts in CO2chemistry owing to their natural origin and high abundance of Lewis acid/base sites and functional groups.Herein,we report the catalytic efficiency of an amino‐acid‐based Cu‐containing MOF,denoted as CuTrp(Trp=L‐tryptophan).The CuTrp catalyst was synthesized by direct mixing at room temperature using methanol as a solvent-a synthetic route with notable energy efficiency.The catalyst was characterized using various physicochemical techniques,including XRD,FT‐IR,TGA,XPS,ICP‐OES,FE‐SEM,and BET analysis.The catalytic activity of CuTrp was assessed in the synthesis of cyclic carbonates from epoxides and CO2.The CuTrp operated in synergy with the co‐catalyst tetrabutylammonium bromide under solvent‐free conditions.Several reaction parameters were studied to identify the optimal reaction conditions and a reaction mechanism was proposed based on experimental evidence and previous density functional theory studies.The CuTrp also exhibited satisfactory stability in water and could be reused more than three times without any significant loss of activity.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved.
文摘This study is aimed at the thermal analysis of sealant mortar （usually a mixtures of bentonite and cemem with addition of sand） used in geothermal cooling and heating. In particular, thermal conductivity and diffusivity measurements were performed on differem sealant mixtures by using Hot Disk thermal constants analyzer in order to identify the interesting thermal properties of grouting materials. The grouting materials that we considered are of porous nature and, if used in the presence of groundwater, have different levels of imbibitions. It is important to know the thermal behavior of these materials at different water content. A first set of measurements was performed on a not-tinted material at room temperature; then the samples were led to saturation conditions by contact capillary imbibitions with a cotton wool layer moistened in water. The determination of thermal conductivity in these test conditions appears to be critical compared to the measuremems on non-timed sample. The thermal conductivity tests have revealed how the thermal behavior of the samples analyzed is essentially determined by the density and water content of the material： in fact, the thermal conductivity increases of two to three times the value of the not-tinted material.
基金the National Natural Science Foundationof China(51303073,51463008,51572117)the Ganpo Outstanding Talents 555 projects(2013)+4 种基金the National Science Fund for Distinguished Young Scholars in Jiangxi Province,Key Project of Jiangxi Educational Committee(GJJ150795)the Natural Science Foundation of Jiangxi Province(20161BAB216130)Scientific Fund of Jiangxi Science & Technology Normal University(2014QNBJRC003)Jiangxi Science & Technology Normal University Program for Scientific Research Innovation Team (2015CXTD001)Scientific Research Foundation for Doctors in Jiangxi Science & Technology
文摘π-Conjugated polymers(CPs)represent one of the quite important and rapidly growing branches of flexible electrochromic materials.Electrosynthesized hybrid CPs employing dibenzo pentacycles(fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran)as the backbones have received considerable attention owing to their special structures and interesting electrochromic performances.Recent studies show that polymers from these structures exhibit decent contrast ratios,favorable coloration efficiencies,low switching voltages,fast response time,excellent stability,and color persistence.Intrinsically,their electrochromic properties significantly depend on fine-tailoring of precursor monomer structures,and polymerization techniques and conditions.This review devotes to showing a clear picture of the research progress of dibenzo pentacycle-centered CPs via electrochemical polymerization,including fluorenes,carbazoles,dibenzothiophenes,and dibenzofuran-based hybrid electrochromic polymers.Critical influences of the tailored precursor structures on their electropolymerization and resultant polymer performances are highlighted,aiming at providing an insight for the development of novel fused ring-based polymer electrochromic materials.
