Two reduction-cleavable ABA triblock copolymers possessing two disulfide linkages,PMMA-ssPMEO3MA-ss-PMMA and PDEA-ss-PEO-ss-PDEA were synthesized via facile substitution reactions from homopolymer precursors,where PMM...Two reduction-cleavable ABA triblock copolymers possessing two disulfide linkages,PMMA-ssPMEO3MA-ss-PMMA and PDEA-ss-PEO-ss-PDEA were synthesized via facile substitution reactions from homopolymer precursors,where PMMA,PMEO3MA,PDEA,and PEO represent poly(methyl methacrylate),poly(tri(ethylene glycol) monomethyl ether methacrylate,poly(2-(diethylamino)ethyl methacrylate),and poly(ethylene oxide),respectively.Spherical micelles were obtained through supramolecular self-assembly of these two triblock copolymers in aqueous solutions.The resultant micelles with abundant disulfide bonds could serve as soft templates and precisely accommodate gold nanoparticles in the core/shell interface as a result of the formation of Au-S bonds.展开更多
A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional solidification.Formation of nanoparticles in the allo...A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional solidification.Formation of nanoparticles in the alloy melt was investigated by performing differential scanning calorimeter tests and designed water quenching experiment at a certain temperature.Results show that iron-rich nanoparticles are formed in the Cu-1wt.%Fe alloy melt before primaryα-Cu forms,which is not consistent with equilibrium phase diagram.Mechanism that iron-rich nanoparticles are uniformly captured in the matrix was described,which is that numerous nanoparticles follow Brownian motions and are engulfed in the solidified matrix which makes it possible to form uniformly distributed nanoparticles reinforced single crystal Cu-1wt.%Fe alloy.展开更多
Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide(CO_2) which contribute to climate change and atmospheric pollution...Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide(CO_2) which contribute to climate change and atmospheric pollution.There is a need for green and sustainable solutions to remove air pollutants,as opposed to conventional techniques which can be expensive,consume additional energy and generate further waste.We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces,to remove CO_2,and undesired organic air pollutants using natural particles,while generating oxygen.This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO_2 with a conversion rate of approximately 4%CO_2 per hour,generating a steady supply of oxygen(6 mmol/hr),while nanoparticles effectively remove several undesired organic by-products.We also showed algal waste of the bioreactor can be used for mercury remediation.We estimated the potential CO_2 emissions that could be captured from our new method for three industrial cases in which,coal,oil and natural gas were used.With a 30% carbon capture system,the reduction of CO_2 was estimated to decrease by about 420,000,320,000 and 240,000 metric tonnes,respectively for a typical 500 MW power plant.The cost analysis we conducted showed potential to scale-up,and the entire system is recyclable and sustainable.We further discuss the implications of usage of this complete system,or as individual units,that could provide a hybrid option to existing industrial setups.展开更多
基金financial support from the National Natural Scientific Foundation of China(NNSFC) Project(Nos.51690150,51690154,and 21674103)Anhui Provincial Natural Scientific Foundation project(No.1508085QB43)
文摘Two reduction-cleavable ABA triblock copolymers possessing two disulfide linkages,PMMA-ssPMEO3MA-ss-PMMA and PDEA-ss-PEO-ss-PDEA were synthesized via facile substitution reactions from homopolymer precursors,where PMMA,PMEO3MA,PDEA,and PEO represent poly(methyl methacrylate),poly(tri(ethylene glycol) monomethyl ether methacrylate,poly(2-(diethylamino)ethyl methacrylate),and poly(ethylene oxide),respectively.Spherical micelles were obtained through supramolecular self-assembly of these two triblock copolymers in aqueous solutions.The resultant micelles with abundant disulfide bonds could serve as soft templates and precisely accommodate gold nanoparticles in the core/shell interface as a result of the formation of Au-S bonds.
文摘A single crystal Cu-1wt.%Fe alloy with finely dispersed iron-rich nanoparticles which keep coherent interface with the copper matrix was prepared under directional solidification.Formation of nanoparticles in the alloy melt was investigated by performing differential scanning calorimeter tests and designed water quenching experiment at a certain temperature.Results show that iron-rich nanoparticles are formed in the Cu-1wt.%Fe alloy melt before primaryα-Cu forms,which is not consistent with equilibrium phase diagram.Mechanism that iron-rich nanoparticles are uniformly captured in the matrix was described,which is that numerous nanoparticles follow Brownian motions and are engulfed in the solidified matrix which makes it possible to form uniformly distributed nanoparticles reinforced single crystal Cu-1wt.%Fe alloy.
基金supported by Natural Sciences and Engineering Research Council of Canada(NSERC)-NSERC CREATE Mine of Knowledge,FRQNT(Fonds de recherche du Québec-Nature et Technologies),and Environment Canada
文摘Fossil fuel combustion and many industrial processes generate gaseous emissions that contain a number of toxic organic pollutants and carbon dioxide(CO_2) which contribute to climate change and atmospheric pollution.There is a need for green and sustainable solutions to remove air pollutants,as opposed to conventional techniques which can be expensive,consume additional energy and generate further waste.We developed a novel integrated bioreactor combined with recyclable iron oxide nano/micro-particle adsorption interfaces,to remove CO_2,and undesired organic air pollutants using natural particles,while generating oxygen.This semi-continuous bench-scale photo-bioreactor was shown to successfully clean up simulated emission streams of up to 45% CO_2 with a conversion rate of approximately 4%CO_2 per hour,generating a steady supply of oxygen(6 mmol/hr),while nanoparticles effectively remove several undesired organic by-products.We also showed algal waste of the bioreactor can be used for mercury remediation.We estimated the potential CO_2 emissions that could be captured from our new method for three industrial cases in which,coal,oil and natural gas were used.With a 30% carbon capture system,the reduction of CO_2 was estimated to decrease by about 420,000,320,000 and 240,000 metric tonnes,respectively for a typical 500 MW power plant.The cost analysis we conducted showed potential to scale-up,and the entire system is recyclable and sustainable.We further discuss the implications of usage of this complete system,or as individual units,that could provide a hybrid option to existing industrial setups.